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    Wyświetlanie 1-69 z 69
    Tytuł:
    Improvement Optical and Electrical Characteristics of Thin Film Solar Cells Using Nanotechnology Techniques
    Autorzy:
    Thabet, Ahmed
    Abdelhady, Safaa
    Ebnalwaled, A.A.
    Ibrahim, A. A.
    Powiązania:
    https://bibliotekanauki.pl/articles/226062.pdf
    Data publikacji:
    2019
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    thin film
    nanoparticles
    nanocomposites
    energy conversion
    optical
    plasmonic
    solar cells
    Opis:
    This work presents a theoretical study for the distribution of nanocomposite structure of plasmonic thin-film solar cells through the absorber layers. It can be reduced the material consumption and the cost of solar cell. Adding nanometallic fillers in the absorber layer has been improved optical, electrical characteristics and efficiency of traditional thin film solar cells (ITO /CdS/PbS/Al and SnO2/CdS/CdTe/Cu) models that using sub micro absorber layer. Also, this paper explains analysis of J-V, P-V and external quantum efficiency characteristics for nanocomposites thin film solar cell performance. Also, this paper presents the effect of increasing the concentration of nanofillers on the absorption, energy band gap and electron-hole generation rate of absorber layers and the effect of volume fraction on the energy conversion efficiency, fill factor, space charge region of the nanocomposites solar cells.
    Źródło:
    International Journal of Electronics and Telecommunications; 2019, 65, 4; 625-634
    2300-1933
    Pojawia się w:
    International Journal of Electronics and Telecommunications
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effectiveness factor of two-dimensional ring-shaped catalyst pellets
    Autorzy:
    Asif, M.
    Ibrahim, A. A.
    Mohammed, Y. A.
    Al-Ghurabi, E. H.
    Powiązania:
    https://bibliotekanauki.pl/articles/780040.pdf
    Data publikacji:
    2017
    Wydawca:
    Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
    Tematy:
    hollow catalyst pellet
    effectiveness factor
    Thiele modulus
    convergence behavior
    analytical solution
    Opis:
    The use of hollow catalytic support improves the utilization of the catalytic material because of the absence of the pellet core, and moreover ensures low reactor pressure drop owing to enhanced bed voidage. In this study, the expressions for the efficient computation of the effectiveness factor are derived for a ring-shaped catalyst pellet undergoing first-order irreversible reaction. The methodology consists of using solutions of one-dimensional problems to remove non-homogeneous boundary conditions. The expressions obtained exhibit significantly faster convergence behavior than those reported in literature. The shape parameters, namely, the height-to-diameter ratio and the inner-to-outer radii ratio, significantly affect the catalyst utilization, such that several-fold improvement in the effectiveness factor is achievable.
    Źródło:
    Polish Journal of Chemical Technology; 2017, 19, 3; 99-105
    1509-8117
    1899-4741
    Pojawia się w:
    Polish Journal of Chemical Technology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Measuring wind gradients in agroforestry systems by shaded piche evaporimeters. II. Accuracies obtained in some African case studies
    Autorzy:
    Stigter, C J
    Kainkwa, R.M.R.
    Oteng'i, S.B.B.
    Onyewotu, L.O.Z.
    Mohammed, A.E.
    Ibrahim, A.A.
    Rashidi, M.G.M.
    Powiązania:
    https://bibliotekanauki.pl/articles/26193.pdf
    Data publikacji:
    2000
    Wydawca:
    Polska Akademia Nauk. Instytut Agrofizyki PAN
    Tematy:
    anemometry
    Piche evaporimeter
    wind reduction
    agroforest system
    Źródło:
    International Agrophysics; 2000, 14, 4
    0236-8722
    Pojawia się w:
    International Agrophysics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Copper (II) Oxide particles as Adsorbent for Removal of Alkali Blue; Isotherm and Kinetic Studies
    Autorzy:
    Ibrahim, M. A.
    Ibrahim, M. B.
    Powiązania:
    https://bibliotekanauki.pl/articles/1158766.pdf
    Data publikacji:
    2018
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Adsorption
    Copper (II) Oxide particles
    FTIR
    Isotherm
    Kinetics
    Opis:
    Adsorption behaviour of copper (II) oxide particles (CuO-Ps) for the removal of Alkali Blue (AB) was studied. Different adsorption variables such as contact time, initial concentration and pH for the adsorption process were investigated by batch adsorption studies. FTIR was carried out to determine the functional groups present at the surface of the particle with functional groups such as –OH, C=C, C-H, C≡C detected. The percentage removal and optimum contact time for the removal of AB was 84.8% at 10 min. The experimental isotherms data were analyzed using Langmuir, Temkin, Freundlich and Dubinin-Radushkevich (D-R) isotherms and it was observed that AB fits closely to Langmuir with R2 value of 0.884. Kinetics studies shows that the adsorption process fits better to pseudo-second order with the experimental values of qe 4.242 been closer to the calculated values of the qe 4.108. Effect of pH shows that it adsorb better at the initial pH of 5.30. Lower value of mean square energy of 0.707 kJ/mol indicates that the adsorption process is physical. The results indicated that copper (II) oxide particle can be used as a low-cost adsorbent for the removal of AB from aqueous solutions.
    Źródło:
    World Scientific News; 2018, 114; 208-217
    2392-2192
    Pojawia się w:
    World Scientific News
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    DESIGN, SYNTHESIS AND BIOLOGICAL ESTIMATION OF INNOVATIVE PYRAZOLES AS ANTICANCER AGENTS TARGETING CDK2
    Autorzy:
    Ibrahim, Diaa A.
    Radini, Ibrahim A.
    KHIDRE, Rizk E.
    Powiązania:
    https://bibliotekanauki.pl/articles/895649.pdf
    Data publikacji:
    2019-06-28
    Wydawca:
    Polskie Towarzystwo Farmaceutyczne
    Tematy:
    Pharmacophore
    binding energy
    pyrazoles
    anti-proliferative activity
    CDK2 inhibitors
    Docking study
    Opis:
    CDK2, which exhibits an indispensable role as an organizer of cell growth, is the powerfully studied protein Kinases objective of anticancer suppressors. The present study was dedicated to design (pharmacophore, docking, and binding energy) and to prepare an inspired derivatives of pyrazole and pyrazolo[1,5-d]pyrimidine as promising anticancer agents, which can act by targeting CDK2. The promising compounds were selected according to their fit-value and binding energy scores. The anticancer activity against MCF-7 was tested for the prepared compounds and compounds 2, 3b, and 7b showed expressive activity with IC50 1.75, 0.89 and 1.32 µM respectively. The CDK2 evaluation was carried out to estimate the efficiency of the prepared compounds as promising inhibitors. The results revealed that compound 3b with effective inhibitory activity against tumor growth and with its potent inhibition against the CDK2 enzyme with percent inhibition 86 would be a prospective anticancer agent. The prepared compounds with high biological activity could be used as lead inhibitors for the CDK2 kinase domain.
    Źródło:
    Acta Poloniae Pharmaceutica - Drug Research; 2019, 76, 3; 453-468
    0001-6837
    2353-5288
    Pojawia się w:
    Acta Poloniae Pharmaceutica - Drug Research
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Non-linearity on pull-out test of cohesive soil using low tensile strengths of geogrids
    Autorzy:
    Widodo, S.
    Ibrahim, A. M.
    Powiązania:
    https://bibliotekanauki.pl/articles/115809.pdf
    Data publikacji:
    2014
    Wydawca:
    Fundacja na Rzecz Młodych Naukowców
    Tematy:
    pull-out test
    tensile strength
    geogrid
    ITD
    non-linear
    Opis:
    Influence of geosynthetics inserted into cohesive granular soil was obviously investigated using geosynthetics-soil-interaction-testing device (ITD). Observations were already made during undertaking pull-out test, and then the results revealed that a correlation between shear stress and normal stress exhibits non-linear behaviour. In this paper, three approaches of trend-lines namely linear, logarithmic, and polynomial were compared. From analysis, polynomial trend line gave the best correlation among others. The final equation is very important part when estimating more accurate values of cohesion and friction angle design purpose.
    Źródło:
    Challenges of Modern Technology; 2014, 5, 1; 34-37
    2082-2863
    2353-4419
    Pojawia się w:
    Challenges of Modern Technology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Molecular docking and prediction of ADME/drug-likeness properties of potentially active antidiabetic compounds isolated from aqueous-methanol extracts of Gymnema sylvestre and Combretum micranthum
    Autorzy:
    Ononamadu, C.J.
    Ibrahim, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/2096363.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    Gymnema sylvestre
    Combretum micranthum
    antidiabetic compounds
    molecular docking
    pharmacokinetics
    drugs
    Opis:
    Gymnema sylvestre and Combretum micranthum are well known for their ethno-medicinal uses in the northwest of Nigeria. In our recent study, we demonstrated the antidiabetic and antioxidant activities of the aqueous-methanol extracts of the two plants and identified some potentially active compounds. The present study aimed to conduct molecular docking and ADME/drug-likeness screening of the identified potentially active candidate compounds from aqueous-methanol extracts of G. sylvestre and C. micranthum leaves by using in silico techniques. Molecular docking of compounds on target proteins (α-amylase, α-glucosidase, and phosphorylated insulin receptor tyrosine kinase) was performed using Molsoft ICM-pro 3.8-3. The physicochemical, ADME, and drug-likeness parameters were computed using the SwissADME online program. The result corroborated the antidiabetic activities of the plants with significant binding interactions between compounds A (2,2-dimethyl-3-[4-(acetyloxy)phenyl]-4-ethyl2H-1-benzopyran-7-ol acetate), D (9,13-di-cis-retinoic acid), E (4-hydroxycinnamic acid), F ((-)-11-hydroxy-9,10-dihydrojasmonic acid), G (colnelenic acid), H (glyinflanin A), I (6,8a-seco-6,8a-deoxy-5-oxoavermectin “2a” aglycone), and J (3-deshydroxysappanol trimethyl ether) and at least one of the three target proteins. Four compounds, namely A (2,2-dimethyl-3-[4-(acetyloxy)phenyl]-4-ethyl-2H-1-benzopyran-7-ol acetate), E (4-hydroxycinnamic acid), H (glyinflanin A), and J (3-deshydroxysappanol trimethyl ether), yielded the best docking scores with respect to the target proteins, of which three (E (4-hydroxycinnamic acid), H (glyinflanin A), and J (3-deshydroxysappanol trimethyl ether)) were identified to have relatively optimal drug-likeness and medicinal chemistry characteristics. Thus, the present study concluded that these compounds may have contributed to the observed antidiabetic properties of these plants and can be investigated further as drugs or drug-like compound candidates.
    Źródło:
    BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology; 2021, 102, 1; 85-99
    0860-7796
    Pojawia się w:
    BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Irrigation and fertigation scheduling under drip irrigation for maize crop in sandy soil
    Autorzy:
    Ibrahim, M.M.
    El-Baroudy, A.A.
    Taha, A.M.
    Powiązania:
    https://bibliotekanauki.pl/articles/26207.pdf
    Data publikacji:
    2016
    Wydawca:
    Polska Akademia Nauk. Instytut Agrofizyki PAN
    Tematy:
    irrigation
    fertigation
    drip irrigation
    maize
    yield
    water productivity
    crop
    sandy soil
    field experiment
    Źródło:
    International Agrophysics; 2016, 30, 1
    0236-8722
    Pojawia się w:
    International Agrophysics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    On a mixed-type integral equation and fractional-order functional differential equations
    Autorzy:
    El-Sayed, A. M. A.
    Sherif, Nagwa
    Ibrahim, I. A.
    Powiązania:
    https://bibliotekanauki.pl/articles/745693.pdf
    Data publikacji:
    2005
    Wydawca:
    Polskie Towarzystwo Matematyczne
    Tematy:
    Nonlinear functional integral equation
    fractional calculus
    Volterra operator
    mixed type integral equation
    Schauder fixed point theorem
    Opis:
    In this paper we study the existence of solution of a nonlinear integral equation of (mixed type) Volterra-Fredholm type. As an application we prove the existence of solution of an initial value problem of fractional order in the space of Lebesgue integrable functions on the interval \([0, 1]\).
    Źródło:
    Commentationes Mathematicae; 2005, 45, 2
    0373-8299
    Pojawia się w:
    Commentationes Mathematicae
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Determination of integral antioxidants capacity in Syrian Hawthorn fruits and flowers using photochemiluminescence assay
    Oznaczanie ogólnej zdolności przeciwutleniającej w owocach i kwiatach głogu z Syrii przy użyciu metody fotochemiluminescencyjnej
    Autorzy:
    Zayzafoon, G.
    Odeh, A.
    Ibrahim, M.
    Allaf, A.W.
    Powiązania:
    https://bibliotekanauki.pl/articles/71723.pdf
    Data publikacji:
    2010
    Wydawca:
    Instytut Włókien Naturalnych i Roślin Zielarskich
    Opis:
    Syrian flora is very well known of its diversity and richness. It contains a large number of medicinal and aromatic species. There are many different hawthorn Crataegus: sinaica, aronia, monogyna and azorolus available in Syria which is mainly located in the western and southern part of the country. Most of these Syrian species are used in folk and in traditional medical care. They are taken in the form of herbal tea to contradict cough, flu and cold. There is no any scientific information available on the antioxidant properties of Syrian hawthorn medicinal plant. Therefore, the assessment of such properties remains an interesting and useful task, particularly for finding a new natural source of antioxidants available in Syria. Therefore, the integral antioxidants, IA of Syrian hawthorn fruits and flowers in five different sites as ascorbic acid equivalents have been carried out using photochemiluminescence, PCL assay of measurements for the first time. By means of a PCL assay, it was possible to assess the integral antioxidant (IA ) using this accurate and simple method, the highest antioxidant capacity values of hawthorn as ascorbic acid equivalents were found in the fruits of Bi’r Al-ajam and Al-Haffa sites which have values of 1444.82 and 483.44 (nmol/g), for C. monogyna and C. aronia cataegus, respectively. The highest fractions of antioxidant components are mainly due to the existence of catechin and flavonoids in both Syrian hawthorn fruit and flowers. Other chemical constituents like elemicin, sorbistat, polygalitol and homocatechol are found in Syrian hawthorn fruit and flowers. The measured values are considered to be the highest among countries of the region.
    Flora Syrii wykazuje dużą różnorodność. W Syrii występuje wiele gatunków z rodzaju głóg Crataegus: sinaica, aronia, monogyna i azorolus. Są one głównie spotykane w zachodniej i południowej części kraju. Wiele z syryjskich gatunków z rodzaju Crataegus jest używanych w medycynie ludowej i tradycyjnej w postaci herbatek ziołowych w leczeniu kaszlu, grypy i przeziębienia. Brak jest naukowych doniesień na temat właściwości przeciwutleniających syryjskich gatunków głogu. Z tego powodu badanie tych właściwości jest interesujące i użyteczne, zwłaszcza w celu znalezienia nowych źródeł przeciwutleniaczy dostępnych na terenie Syrii. W artykule przedstawiono oznaczenia sumy antyoksydantów (ang. Integral antioxidants, IA ) w przeliczeniu na kwas askorbinowy, wykonane dla syryjskich głogów (owoców i kwiatów), zebranych z pięciu różnych stanowisk. Oznaczenia te po raz pierwszy wykonane były przy zastosowaniu metody fotochemiluminescencyjnej (ang. PCL assay). Stwierdzono, że najwyższa wartość zdolności przeciwutleniających w przeliczeniu na kwas askorbinowy została oznaczona dla owoców ze stanowisk Bi’r Al.-ajam i Al.-Haffa, dla których wartości te wyniosły odpowiednio 1444,82 i 483,44 (nmol/g). Otrzymane wartości można uważać za najwyższe w stosunku do wartości podawanych w innych państwach w tym regionie.
    Źródło:
    Herba Polonica; 2010, 56, 2
    0018-0599
    Pojawia się w:
    Herba Polonica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Structural and Optical Properties of Nanostructured Fe-Doped SnO₂
    Autorzy:
    Saleh, S.
    Ibrahim, A.
    Mohamed, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/1398977.pdf
    Data publikacji:
    2016-06
    Wydawca:
    Polska Akademia Nauk. Instytut Fizyki PAN
    Tematy:
    81.07.-b
    61.05.C-
    78.20.-e
    Opis:
    Nanocrystalline $Sn_{1-x}Fe_xO_2$ (where x = 0, 0.01, 0.02, 0.03 and 0.04) powders have been successfully synthesized by the hydrothermal method followed by sintering at 1000°C for 3 h. The morphology and structure of the samples have been analyzed by field emission scanning electron microscope and X-ray diffraction, respectively. X-ray diffraction results revealed that all diffraction peaks positions agree well with the reflection of a tetragonal rutile structure of SnO₂ phase without extra peaks. The formation of a tetragonal rutile structure of SnO₂ nanostructures was further supported by the Raman spectra. The band gap of Fe-doped SnO₂ nanoparticles was estimated from the diffuse reflectance spectra using the Kubelka-Munk function and it was decreasing slightly with the increase of Fe ion concentration from 3.59 to 3.52 eV. The variation in band gap is attributed predominantly to the lattice strain and particle size. The presence of chemical bonding was confirmed by the Fourier transform infrared spectra.
    Źródło:
    Acta Physica Polonica A; 2016, 129, 6; 1220-1225
    0587-4246
    1898-794X
    Pojawia się w:
    Acta Physica Polonica A
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Analysis of different equations of undrained shear strength estimations using Atterberg Limits on Pontianak Soft Clay
    Autorzy:
    Widodo, S.
    Ibrahim, A.
    Hong, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/115700.pdf
    Data publikacji:
    2012
    Wydawca:
    Fundacja na Rzecz Młodych Naukowców
    Tematy:
    undrained shear strength
    Atterberg limits
    cohesion
    soft clay
    Opis:
    Many researchers have done study to estimate the value of undrained shear strength for fine grained soils like clay or silt. Determining of undrained shear strength and compressibility parameters in laboratory are really tedious and time consuming. Therefore, a correlation between undrained shear strength and Atterberg limits is useful for restraint of testing number and costs. Central tendency parameters such as an average, deviation standard and coeffi cient of variation are performed to analyze the data of soft clay in Pontianak, Indonesia. Based on analysis that undrained shear strength coincides with 50 percentile of distribution data meanwhile undrained compressive strength is around twice of cohesion for testing using unconfi ned pressure. This relationship is the most familiar equation. Moreover, undrained shear strength using mean value is more realistic for correlation between undrained shear strength and Atterberg limits on some equations from previous findings.
    Źródło:
    Challenges of Modern Technology; 2012, 3, 3; 46-50
    2082-2863
    2353-4419
    Pojawia się w:
    Challenges of Modern Technology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Parametric study simulation of axially loaded ored pile using finite element ode—Plaxis Software on subsurface soils Khartoum area-Sudan
    Autorzy:
    Ibrahim, A. M.
    Widodo, S.
    Hong, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/115670.pdf
    Data publikacji:
    2012
    Wydawca:
    Fundacja na Rzecz Młodych Naukowców
    Tematy:
    bored pile
    finite code
    plaxis software
    Opis:
    The diversity and complexity of subsurface soil in studied area consisting of alluvial deposits cause many diffi culties for foundation engineering. Therefore, a solution is needed for foundation in this problematic soil. In Sudan, raft foundation represents the basic and most widespread shallow foundation method for engineering structure except for bridges where the pile foundation is used. In recent years, after the discovery of petroleum in Sudan, a major advance in piling technology is needed due to intensive building of large numbers of precast high-rise tower. This paper used Plaxis software to understand the behavior of axially loaded bored pile using different loads, lengths and diameters of piles. In this paper a comprehensive analytical study using fi nite element analysis is presented and parametric study of pile under vertical load is performed. The analytical and quantitative analysis in this study shows useful understanding of the behavior of bored pile.
    Źródło:
    Challenges of Modern Technology; 2012, 3, 3; 33-38
    2082-2863
    2353-4419
    Pojawia się w:
    Challenges of Modern Technology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Primates Associated with Crop Raiding Around Borgu Sector of Kainji Lake National Park, Nigeria
    Autorzy:
    Adeola, A. J.
    Ibrahim, A. O.
    Adeola, A. N.
    Alaye, S. A.
    Akande, O. A.
    Powiązania:
    https://bibliotekanauki.pl/articles/1112666.pdf
    Data publikacji:
    2018
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Borgu sector
    Chlorocebus aethiops
    Community and Kainji Lake National Park
    Erthrocebus patas
    Papio anubis
    Primates
    Raiding
    Opis:
    Crop raiding activities of primates around Kainji Lake National Park (Borgu Sector), Nigeria was investigated with the use of questionnaires, complemented with field survey focus group discussions and in-depth interviews. One hundred (100) questionnaires were administered to representatives of households in four selected support zone villages. Group discussions were then conducted in the villages. Data collected were analyzed using descriptive statistics in the form of percentages, frequencies and charts. We found that crop raiding and animal depredation were sources of conflict in Kainji Lake National Park (Borgu Sector). The primates raiding farmlands identified by the farmers were Olive Baboon (Papio anubis), Patas monkey (Erthrocebus patas), green monkey (Chlorocebus aethiops) and other primates that could not be identified by the farmers. The largest percentage of raiding (40%) was perpetrated by Papio anubis, followed by Patas monkey (35%) and the least by Green Monkey (2%). The result showed that maize was the most commonly ranked crop of seasonal harvest that was lost. Moreover, an estimated 3-5 50 kg bags of seed were being destroyed in the planting season. The most effective strategy the local communities used in preventing crop damage was watch guarding (70%). Other methods were fencing (60%), hunting (45%), scare crow (36%) and toxic chemical (5%). The mitigation measure advocated by nearly all respondents (57%) was the killing of destructive wildlife species, irrespective of conservation significance. Measures must put in place to educate these communities about wildlife conservation and to prevent wanton killing. The communities should also be compensated for their loss, as this will lead to positive attitudes to wildlife conservation.
    Źródło:
    World News of Natural Sciences; 2018, 18, 2; 223-231
    2543-5426
    Pojawia się w:
    World News of Natural Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Spatial distribution prediction for the ground water quality in Mosul City (Iraq) using variogram equations
    Autorzy:
    Al-Tamir, Mus'ab A.
    Ibrahim, Abdullah
    Powiązania:
    https://bibliotekanauki.pl/articles/36063299.pdf
    Data publikacji:
    2023
    Wydawca:
    Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Wydawnictwo Szkoły Głównej Gospodarstwa Wiejskiego w Warszawie
    Tematy:
    GIS
    geospatial interpolation
    groundwater quality
    kriging
    semivariogram model
    Opis:
    The GIS-aided spatial interpolation was applied on collected groundwater data to predict selected parameters (i.e., pH, electrical conductivity, and temperature) for the selected water wells distributed over Mosul City in Iraq. A descriptive statistical analysis was conducted on collected samples to explore the statistical indices. The skewness test was also employed to test the distribution of data sets around their mean values. The natural logarithms function achieved least skewness values and thus was applied to transfer data sets in order to adjust normality of the data sets distribution. Among all applied semivariogram models, the J-Bessel semivariogram model was optimal in terms of root mean square error (RMSE) values. The average standard errors were 0.2217, 740.5, and 1.209 for pH, EC, and temperature, respectively.
    Źródło:
    Scientific Review Engineering and Environmental Sciences; 2023, 32, 2; 186-197
    1732-9353
    Pojawia się w:
    Scientific Review Engineering and Environmental Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Czynnik stymulujący tworzenie kolonii granulocytów (G-CSF) jako nowy biomarker w spersonalizowanej terapii raka jelita grubego?
    Granulocyte colony stimulating factor (G-CSF) as a new biomarker for personalized treatment of colorectal cancer?
    Autorzy:
    Wawrzyniec, K.
    Kawczyk-Krupka, A.
    Flak, B.
    Ibrahim, O.
    Sieroń, A.
    Powiązania:
    https://bibliotekanauki.pl/articles/261427.pdf
    Data publikacji:
    2013
    Wydawca:
    Politechnika Wrocławska. Wydział Podstawowych Problemów Techniki. Katedra Inżynierii Biomedycznej
    Tematy:
    G-CSF
    rak jelita grubego
    terapia spersonalizowana
    colon cancer
    personalized therapy
    Opis:
    Rak jelita grubego jest drugą przyczyną zgonów w populacji pacjentów onkologicznych. Pomimo ciągłego rozwoju metod diagnostycznych, wprowadzania programów badań przesiewowych, systematycznej kontroli pacjentów będących już po interwencji chirurgicznej lub chemioterapii, osiągane finalne efekty przeżycia chorych z rakiem jelita grubego nie są zadowalające. Przyczyną tak niesatysfakcjonujących wyników jest częste wykrywanie choroby już w zaawansowanym stadium, gdyż u co trzeciego chorego w momencie rozpoznania raka jelita grubego potwierdzone są przerzuty. Powszechnie stosowane, celem detekcji zmian nowotworowych i późniejszej kontroli nawrotu choroby, markery CEA i CA 19-9 nie są wystarczające. Z tego powodu konieczne są dalsze poszukiwania znaczników, które w połączeniu z dotychczas stosowanymi elementami diagnostycznymi, umożliwią z wysoką czułością i swoistością wykrycie raka, wznowy i progresji choroby oraz pozwolą przewidzieć przebieg, a także prawdopodobną odpowiedź na standardowe leczenie. Oparcie podejmowanych decyzji na takich danych i kwalifikowanie pacjenta do niestandardowego schematu leczniczego umożliwi w większym stopniu wdrożenie zindywidualizowanej terapii, która powinna odgrywać podstawową rolę w leczeniu.
    The colorectal cancer (CRC) is the second cause of death in the entire population of oncological patients. Despite of the development of diagnostic methods, screening programs, monitoring of patients after surgery or chemotherapy, results of survival rates are not satisfactory. The reason is that frequently the detection of the disease takes place already at the advanced stage, as every third patient at the time of diagnosis of CRC has already metastases. CEA and CA 19-9 markers are commonly used to detect cancer and to monitor the disease recurrence, are not sufficient. For this reason it becomes necessary to introduce new additional markers that will enable a higher sensitivity and specificity for detecting cancer, it’s recurrence and progression and will be helpful to predict the course of disease and response to standard therapy. Basing on an advanced diagnosis, an individualized therapy implementation will be possible. This approach should play a key role in the proper treatment.
    Źródło:
    Acta Bio-Optica et Informatica Medica. Inżynieria Biomedyczna; 2013, 19, 3; 148-153
    1234-5563
    Pojawia się w:
    Acta Bio-Optica et Informatica Medica. Inżynieria Biomedyczna
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Synthesis and properties of vinylpyrrolidone/ (trimethoxysilyl)propyl methacrylate gels containing different amounts of crosslinking agent
    Synteza i właściwości żelu N-winylopirolidon/metakrylan3-(trimetoksysililo)propylu z różną zawartością czynnika sieciującego
    Autorzy:
    Mohammed, A. H.
    Ahmad, M. B.
    Ibrahim, N. A.
    Zainuddin, N.
    Powiązania:
    https://bibliotekanauki.pl/articles/947044.pdf
    Data publikacji:
    2018
    Wydawca:
    Sieć Badawcza Łukasiewicz - Instytut Chemii Przemysłowej
    Tematy:
    high conversion copolymers
    swelling parameters
    mechanical properties
    oxygen permeability
    crosslinking density
    kopolimery o wysokim stopniu konwersji
    parametry pęcznienia
    właściwości mechaniczne
    przepuszczalność tlenu
    gęstość sieciowania
    Opis:
    High conversion copolymers containing 90 wt % of N-vinylpyrrolidone (NVP) and 10 wt % of 3-(trimethoxysilyl)propyl methacrylate (TMSPM) with 0, 1, 2, 3 and 4 wt % (in conversion to mass of NVP/TMSPM) of ethylene glycol dimethacrylate (EGDMA) as crosslinker have been successfully synthesized. Proton nuclear magnetic resonance (1H NMR) and Fourier transform infrared spectroscopy (FT-IR) were employed to characterize the resulting copolymers. The effect of EGDMA amount on the mechanical and thermal properties, swelling parameters, clarity, and oxygen permeability of the prepared xerogels and hydrogels were studied. 3 wt % of EGDMA is required to obtain clear xerogels and hydrogels. The water content (EWC), volume fraction of polymer (φ2) and weight loss during swelling decrease with increasing EGDMA content. Young’s and shear modulus (E and G) increase as EGDMA content increases, the values of E and G are 0.570–3.531 MPa and 0.217–1.359 MPa, respectively. The hydrogels were characterized in terms of modulus crosslinking density (ve and vt) and polymer-solvent interaction parameters (χ). The results are 0.220–0.613 mol/dm3 for ve, 0.105–0.441 mol/dm3 for vt, and 0.595–0.822 for χ. Thermal properties enhance by adding EGDMA whereas the oxygen permeability (P) of hydrogels decreases from 48.6 to 44.3 as water content decrease from 70.3 to 55.1.
    Kopolimery zawierające 90 % mas. N-winylopirolidonu (NVP) i 10 % masmetakrylanu 3-(trimetoksysililo)propylu (TMSPM) z udziałem 0, 1, 2, 3 i 4 % mas. (w przeliczeniu na masę NVP/TMSPM) dimetakrylanu glikolu etylenowego (EGDMA) jako środka sieciującego zsyntetyzowano z wysokim stopniem konwersji. Otrzymane kopolimery charakteryzowano metodami protonowego rezonansu jądrowego (H1 NMR) i spektroskopii w podczerwieni (FT-IR). Badano wpływ udziału środka sieciującego na właściwości mechaniczne i termiczne, parametry pęcznienia, klarowność i przepuszczalność tlenu wytworzonych hydro- i kserożeli. Stwierdzono, że dodatek już 3 % mas. EGDMA wystarcza do uzyskania klarownego żelu, a w miarę zwiększania zawartości EGDMA zmniejsza się zawartość wody (EWC), ułamek objętości polimeru (φ2) oraz strata masy w procesie pęcznienia żelu NVP/TMSPM. Wartość modułu zarówno Younga (E), jak i ścinania (G) zwiększa się (E = 0,570–3,531 MPa, G = 0,217–1,359 MPa) wraz ze wzrostem udziału EGDMA w kompozycji. Wytworzone hydrożele charakteryzowano za pomocą modułów gęstości sieciowania (ve = 0,220–0,613 mol/dm3, vt = 0,105–0,441 mol/dm3) i parametru oddziaływania polimer-rozpuszczalnik (χ = 0,595–0,822). Właściwości termiczne otrzymanych hydrożeli zawierających EGDMA poprawiły się wraz ze zmniejszeniem zawartości wody (70,3–55,1), natomiast przepuszczalność tlenu się pogorszyła (P = 48,6–44,3).
    Źródło:
    Polimery; 2018, 63, 9; 577-585
    0032-2725
    Pojawia się w:
    Polimery
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Synthesis and monomer reactivity ratios of acrylamide with 3-(trimethoxysilyl)propyl methacrylate and tris(methoxyethoxy)vinylsilane copolymers
    Współczynniki reaktywności monomerów w syntezie kopolimerów akryloamidu, metakrylanu 3-(trimetoksysililo)propylu i tris(metoksyetoksy)-winylosilanu
    Autorzy:
    Mohammed, A. H.
    Ahmad, M. B.
    Ibrahim, N. A.
    Zainuddin, N.
    Powiązania:
    https://bibliotekanauki.pl/articles/947173.pdf
    Data publikacji:
    2016
    Wydawca:
    Sieć Badawcza Łukasiewicz - Instytut Chemii Przemysłowej
    Tematy:
    vinylsilane monomers
    acrylamide
    reactivity ratios
    sequence distribution
    sekwencja monomerów
    Opis:
    Copolymers of acrylamide (AM) with 3-(trimethoxysilyl)propyl methacrylate (TMSPMA) and tris(methoxyethoxy)vinylsilane (TMEVS) with different compositions were synthesized at low conversion by free radical polymerization in dimethylformamide (DMF) using benzoyl peroxide (BPO) as an initiator. The copolymers were characterized by Fourier transform infrared spectroscopy (FT-IR), and their thermal properties were studied by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The copolymers composition was determined by elemental analysis. The monomer reactivity ratios were estimated by linearization methods proposed by Fineman-Ross and Kelen-Tudos, the intersection method proposed by Mayo-Lewis and nonlinear method proposed by curve fitting procedure. The derived reactivity ratios (r1, r2) are: 1.87, 0.80 for TMSPMA-co-AM and 0.22, 1.21 for TMEVS-co-AM. Both copolymers formed blocks of one of the monomer units. The microstructure of copolymers and sequence distribution of monomers in the copolymers were calculated by statistical method based on the average reactivity ratios and found that these values are in agreement with the derived reactivity ratios.
    Kopolimery akryloamidu (AM) z metakrylanem 3-(trimetoksysililo)propylu (TMSPMA) itris(metoksyetoksy)winylosilanem (TMEVS), o różnych składach, zsyntetyzowano w warunkach małej konwersji metodą wolnorodnikowej polimeryzacji w dimetyloformamidzie (DMF), z zastosowaniem nadtlenku benzoilu (BPO) jako inicjatora. Otrzymane kopolimery charakteryzowano za pomocą spektroskopii w podczerwieni z transformacją Fouriera (FT-IR), różnicowej kalorymetrii skaningowej (DSC) oraz analizy termograwimetrycznej (TGA). Skład kopolimerów ustalono metodą analizy elementarnej. Współczynniki reaktywności monomerów oszacowano metodami linearyzacji zaproponowanymi przez: Finemana-Rossa, Kelena-Tudosa, Mayo-Lewisa i metodą nieliniową z zastosowaniem procedury dopasowania krzywej. Otrzymane współczynniki reaktywności (r1, r2) wynosiły: 1,87 i 0,80 dla TMSPMA-co-AM oraz 1,21 i 0,22 dla TMEVS-co-AM. Oba kopolimery miały budowę złożoną zbloków utworzonych z jednostek monomerów składowych. Mikrostrukturę oraz sekwencję monomerów w kopolimerach wyznaczono metodą statystyczną na podstawie średnich współczynników reaktywności. Stwierdzono zgodność obliczeń z wartościami otrzymanymi doświadczalnie.
    Źródło:
    Polimery; 2016, 61, 11-12; 758-765
    0032-2725
    Pojawia się w:
    Polimery
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect of 2014 massive flood on well water qualities: A case study on Kelantan River basin, Malaysia
    Wpływ ekstremalnej powodzi z 2014 roku na jakość wód w studniach: Przykład basenu rzeki Kelantan w Malezji
    Autorzy:
    Rahman, H. A. Ab.
    Ibrahim, N. A.
    Abdul Hamid, A. A.
    Abdul Hamid, T. H. T.
    Powiązania:
    https://bibliotekanauki.pl/articles/292275.pdf
    Data publikacji:
    2018
    Wydawca:
    Instytut Technologiczno-Przyrodniczy
    Tematy:
    drinking well
    flood inundation
    Kelantan River basin
    total coliform
    water quality
    bakterie typu coli
    basen rzeki Kelantan
    jakość wody
    woda pitna
    zalanie wodami powodziowymi
    Opis:
    The effect of physical and biological qualities of wells after submergence was assessed following December 2014 flood in Kelantan. Studies were carried out on a total of 65 wells from 13 stations around Kelantan River basin in which the wells’ water were sampled for pH, total dissolved solid (TDS), turbidity and microbial contamination. About 95% of the well showed to be contaminated, 7 out of 65 samples (11.1%) showed TDS values >400 μS·cm–1; and 19 samples (29.2%) recorded turbidity beyond 7.0 NTU. Statistical non-parametric tests carried out on independent groups showed that the status of well contamination was neither determined by both degree of submergence nor by the geographical location. Also the physico-chemical parameters are independent of flood inundation. However, TDS and turbidity values changed based on geographical location, at p < 0.05. Well from estuary recorded higher TDS (241.2 μS·cm–1 ±159.5 SD) and turbidity (8.04 NTU ± 6.53 SD) compared to those from inner basin (TDS at 156.3 μS·cm–1± 88.9 SD; turbidity at 2.90 NTU ± 2.46 SD), respectively. The flood water had played significant role in the transmission of existing contaminant, and most of the wells were unsafe for drinking. We concluded that the degree of flood submergence does not necessarily determine the severity of the well contamination in Kelantan, but the existing contamination may exacerbate further the potential risk during post flood period.
    Oceniano fizyczne i biologiczne właściwości wód w studniach zalanych w wyniku powodzi w grudniu 2014 r. w basenie rzeki Kelantan. Badania prowadzono łącznie w 65 studniach z 13 stanowisk w basenie rzeki. Analizowano pH, zawartość substancji rozpuszczonych (TDS), mętność i zanieczyszczenie mikrobiologiczne. Zanieczyszczenia wykryto w ok. 95% studni, w 7 z 65 stwierdzono wartości TDS > 400 μS·cm–1, a 19 próbek (29,2%) miało mętność ponad 7,0 NTU. Statystyczne testy dla zmiennych niezależnych wykazały, że poziom zanieczyszczeń nie zależał ani od stopnia zalania, ani od lokalizacji. Fizyczne i chemiczne parametry wody także nie były zależne od zalewu powodziowego, TDS i mętność zmieniały się wraz z położeniem geograficznym z istotnością p < 0,05. W wodzie ze studni z estuarium rzeki wartości TDS i mętność (odpowiednio 241,2 μS·cm–1 ±159,5 SD i 8,04 NTU ±6,53 SD) były większe niż w wodzie ze studni w głębi basenu (TDS 156,3 μS·cm–1 ±88,9 SD, mętność 2,90 NTU ±2,46 SD). Wody powodziowe odgrywały istotną rolę w przenoszeniu zanieczyszczeń. Większość wód studziennych nie nadawała się do picia. Stwierdzono ostatecznie, że stopień zalania studni niekoniecznie determinuje stopień zanieczyszczenia studni, ale występujące zanieczyszczenia mogą zwiększać potencjalne ryzyko po ustąpieniu powodzi.
    Źródło:
    Journal of Water and Land Development; 2018, 38; 127-136
    1429-7426
    2083-4535
    Pojawia się w:
    Journal of Water and Land Development
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Three-phases bubble column to polyethylene terephthalate depolymerization for cement mortar composites improvement
    Autorzy:
    Hameed, A. M.
    Alzuhairi, M.
    Ibrahim, S. I.
    Powiązania:
    https://bibliotekanauki.pl/articles/2172162.pdf
    Data publikacji:
    2022
    Wydawca:
    Stowarzyszenie Komputerowej Nauki o Materiałach i Inżynierii Powierzchni w Gliwicach
    Tematy:
    depolymerization
    DPET
    plastic waste
    bubble column
    mortar
    water absorption
    flexural strength
    depolimeryzacja
    odpady z tworzyw sztucznych
    kolumna barbotażowa
    zaprawa
    absorpcja wody
    wytrzymałość na zginanie
    Opis:
    Purpose This paper aims to prepare depolymerized polyethylene terephthalate (DPET) powder from recycled plastic water bottles. Adding this DPET powder to the cement mortar was also studied. Design/methodology/approach The adopted PET depolymerization process includes the usage of both ethylene glycol (EG) as solvent and nano-MgO as a catalyst. A bubble column reactor was designed for this process. Five different mortar groups were made; each has different DPET content of 0%, 1%, 3%, 6% and 9% as a sand replacement. The flexural strength test and the water absorption measurement are done after two curing periods: 7 and 28 days. Findings The research finding demonstrated that the flexural strength of mortar was reduced by increasing the DPET powder percentage and the maximum dropping was 15% when 9% of DPET was added. The ability of the mortar to absorb the water was reduced by 14.5% when DPET powder was 9%. The mortar microstructure is featured with fewer cavities and porosity. Research limitations/implications This work’s employed bubble column technique is limited only to the laboratory environment and needs to be scaled up within industrial mass production. For future research, it is suggested to decrease depolymerization time by using smaller pieces of plastic water bottle waste and trying other types of nanocatalyst. Practical implications The modified mortar can be utilized in areas where moisture, rainfalls, and sanitation systems exist. Originality/value The article claims that depolymerized waste PET improves chemical process efficiency by lowering reaction time and improving mass and heat transfer rates. Besides, this approach saves money. It is found out that the depolymerized plastic waste is much more functional due to its high cohesion capability than being used as small PET pieces.
    Źródło:
    Journal of Achievements in Materials and Manufacturing Engineering; 2022, 112, 1; 5--12
    1734-8412
    Pojawia się w:
    Journal of Achievements in Materials and Manufacturing Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Rain-fed plantations of the domesticated Ziziphus mauritiana in the Sahel: effects of varieties and rootstocks on yields and fruit quality
    Autorzy:
    Ibrahim, A.
    Pasternak, D.
    Guimbo, I.D.
    Saidou, A.S.
    Amadou, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/2109.pdf
    Data publikacji:
    2015
    Wydawca:
    Instytut Ogrodnictwa
    Tematy:
    Ziziphus mauritiana
    domestication
    variety
    rootstock
    agroecology
    Niger
    annual rainfall
    fruit yield
    fruit weight
    Źródło:
    Journal of Horticultural Research; 2015, 23, 1
    2300-5009
    Pojawia się w:
    Journal of Horticultural Research
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Mitigation of salinity stress effects on growth, physio-chemical parameters and yield of snapbean (Phaseolus vulgaris L.) by exogenous application of glycine betaine
    Autorzy:
    Desoky, E-S.M.
    Ibrahim, S.A.
    Merwad, A-R.M.
    Powiązania:
    https://bibliotekanauki.pl/articles/11220.pdf
    Data publikacji:
    2019
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Źródło:
    International Letters of Natural Sciences; 2019, 76
    2300-9675
    Pojawia się w:
    International Letters of Natural Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Design of a Solar Powered Reverse Osmosis System in Egypt
    Autorzy:
    Ibrahim, Said M. A.
    Shabak, Ahmed G. M.
    Powiązania:
    https://bibliotekanauki.pl/articles/2052247.pdf
    Data publikacji:
    2021
    Wydawca:
    Politechnika Koszalińska. Wydawnictwo Uczelniane
    Tematy:
    reverse osmosis
    photovoltaic
    total dissolved solids
    TDS
    pvro
    desalination
    odwrócona osmoza
    fotowoltaika
    całkowita ilość rozpuszczonych w płynie substancji
    odsalanie
    Opis:
    Scarcity of fresh water, forced many countries to get their water needs, or part of it, by means of saline water desalination. Reverse osmosis (RO) systems are useful tools in this concern. In case the grid electricity is not available or costly, photovoltaic (PV) power is necessary to derive RO systems. The present paper is concerned with providing a methodology for complete sizing and design of a photovoltaic reverse osmosis (PVRO) system in Egypt. Egypt has very favorable solar energy. A computer program was constructed to solve the mathematical equations of the model to get the numerical values. The program is capable of calculating the solar irradiation for any city in Egypt. Calculations and selection of the RO system with all connected pumps, the peak PV power needed, and the actual PV area were performed for different water demands ranging from 1-100 m3/day, and various water total dissolved solids (TDSs) of 5000, 15000, and 30000 mg/l. The cost of the complete PVRO system was also determined. The concern of the paper is related to water desalination and solar energy, which are responsible for our existence. The work also aims toward sustainable and clean environment via utilizing solar energy.
    Źródło:
    Journal of Mechanical and Energy Engineering; 2021, 5, 2; 125-140
    2544-0780
    2544-1671
    Pojawia się w:
    Journal of Mechanical and Energy Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Industrial noise level study in a wheat processing factory in Ilorin, Nigeria
    Autorzy:
    Ibrahim, I.
    Ajao, K. R.
    Aremu, S. A.
    Powiązania:
    https://bibliotekanauki.pl/articles/265416.pdf
    Data publikacji:
    2016
    Wydawca:
    Uniwersytet Zielonogórski. Oficyna Wydawnicza
    Tematy:
    poziom szumów
    cyfrowy miernik szumów
    hałas
    wheat processing
    noise level
    digital sound meter
    questionnaire
    hearing protector
    Opis:
    An industrial process such as wheat processing generates significant noise which can cause adverse effects on workers and the general public. This study assessed the noise level at a wheat processing mill in Ilorin, Nigeria. A portable digital sound level meter HD600 manufactured by Extech Inc., USA was used to determine the noise level around various machines, sections and offices in the factory at pre-determined distances. Subjective assessment was also mode using a World Health Organization (WHO) standard questionnaire to obtain information regarding noise ratings, effect of noise on personnel and noise preventive measures. The result of the study shows that the highest noise of 99.4 dBA was recorded at a pressure blower when compared to other machines. WHO Class-4 hearing protector is recommended for workers on the shop floor and room acoustics should be upgraded to absorb some sounds transmitted to offices.
    Źródło:
    International Journal of Applied Mechanics and Engineering; 2016, 21, 2; 511-523
    1734-4492
    2353-9003
    Pojawia się w:
    International Journal of Applied Mechanics and Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Exploitation of industrial solid wastes for preparing zeolite as a value-added product and its kinetics as adsorbent for heavy metal ions
    Autorzy:
    Abdel-Hameed, Reham Mohamed
    Abdel-Aal, Elsayed A.
    Farghaly, Fatma E.
    Ibrahim, Ibrahim A.
    Abdel Khalek, Mohamed A.
    Ahmed, Mohamed A.
    Abdel-Messih, Micheal F.
    Powiązania:
    https://bibliotekanauki.pl/articles/1448799.pdf
    Data publikacji:
    2021
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    zeolite P
    aluminium wastes
    hydrothermal process
    metal ion removal
    aluminum waste
    Opis:
    Aluminum and fumed silica as solid industrial wastes were converted to zeolite NaPas a value-addedproduct without any template. The hydrothermal process was optimized using static autoclave. The crystallization was carried out at 100, 120 and 150°C for 24, 48 and 72 h. The prepared zeolite of Si:Al ratio of 1.2 was characterized using X-ray Diffraction (XRD), Scanning Electron Microscope (SEM) provided with Energy Dispersive Spectroscopy (EDS), Surface Area, Fourier Transmitted Infra-Red (FTIR) and Thermal Analysis (TG-DSC). The crystalline phase was formed at 100°Cafter 72 hours and at 120°C after 48 hours, while it was formed after 24 honlyat 150°C. Increasing temperature and time lead to the conversion of the prismatic gibbsite crystals into plate-like structure of zeolitewhich is then formedcauliflower-like structure.The prepared zeolite was employed as adsorbent for $Ni^{2+}$ and $Cu2+ions from aqueous solution.The kinetic studies of adsorption processes were performed.
    Źródło:
    Physicochemical Problems of Mineral Processing; 2021, 57, 1; 87-99
    1643-1049
    2084-4735
    Pojawia się w:
    Physicochemical Problems of Mineral Processing
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Celestite upgrading by jigs in presence of steel balls as ragging material
    Autorzy:
    Sobhy, Ahmed
    El-Midany, Ayman A.
    Ibrahim, Susan S.
    Powiązania:
    https://bibliotekanauki.pl/articles/1447020.pdf
    Data publikacji:
    2021
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    celestite
    calcite
    jigging
    ragging material
    gravity separation
    statistical analysis
    Opis:
    Gravity separation using jigs is widely used for coarse particle sizes separation. However, fine sizes reduce jig performance. In this study, the upgrading of celestite ore by jig was investigated at different size fractions in the presence of ragging material. Three size fractions, i.e., -15+2 mm, - 2.0 + 0.50 mm and - 0.50 + 0.08 mm were used. The steel balls were used, as ragging material, to improve the separation of fines as well as to improve the concentrate quality. The statistical design was used to correlate celestite grade and recovery with studied operating variables, i.e., the ragging number of layers, ragging balls diameter, and separation time, at a fixed water flow rate and stroke length. The design results indicated that the ragging balls diameter and their number of layers play an important role. The smaller the ragging balls diameter and the higher the ragging number of layers are the better the concentrate grade but the longer the separation time. A celestite concentrate of (> 95% SrSO4) with 74.5% recovery was obtained for - 2.0 + 0.50 mm size fraction at the optimum conditions; i.e., 3.1 mm ragging balls diameter, one ragging layers, and 15 minutes separation time.
    Źródło:
    Physicochemical Problems of Mineral Processing; 2021, 57, 5; 118-128
    1643-1049
    2084-4735
    Pojawia się w:
    Physicochemical Problems of Mineral Processing
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Minerals content, essential oils composition and physicochemical properties of Citrus jambhiri Lush. (Rough Lemon) from the Sudan
    Autorzy:
    Mohammed, A. M. H.
    Ibrahim, M. A
    Omran, A. A.
    Mohamed, E. M.
    Elsheikh, S. E. M.
    Powiązania:
    https://bibliotekanauki.pl/articles/412508.pdf
    Data publikacji:
    2013
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Citrus jambhiri
    Rutaceae
    atomic absorption spectroscopy (AAS)
    Flame Atomic Emission Spectroscopy (FAES)
    metal content
    essential oils
    Opis:
    Minerals content of Citrus jambhiri (rough lemon) fruit was qualitatively and quantitatively analyzed using atomic absorption spectroscopy (AAS) and flame atomic emission spectrometry (FAES). The peel, moisture and ash contents of rough lemon were found to be 18.35 %, 23.75 % and 2.04 % respectively. Vitamin C (ascorbic acid) of rough lemon juice was found to be 70.0 mg/100 g. The chemical composition of essential oil of rough lemon peel was determined. The major compound was found to be limonene (84.5 %) followed by sabinene, β-myrcene, α-terpineol, 1,3-tetradecadiene and linalool.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2013, 9, 1; 25-30
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Synthesis, characterization and thermal polymerization of new 3,4-dihydro-2H-1,3-naphthoxazine monomers
    Synteza, charakterystyka i polimeryzacja termiczna nowych monomerów 3,4-dihydro-2H-1,3-naftoksazynowych
    Autorzy:
    Gabbas, A. U. G.
    Ahmad, M. B. H.
    Zainuddin, N.
    Ibrahim, N. A.
    Powiązania:
    https://bibliotekanauki.pl/articles/946991.pdf
    Data publikacji:
    2017
    Wydawca:
    Sieć Badawcza Łukasiewicz - Instytut Chemii Przemysłowej
    Tematy:
    1,3-naphthoxazine
    polynaphthoxazine
    thermal polymerization
    thermal properties
    1,3-naftoksazyna
    polinaftoksazyna
    polimeryzacja termiczna
    właściwości termiczne
    Opis:
    Two new 1,3-naphthoxazine monomers (M-A and M-B) were synthesized via a modified stepwise procedure in which methylene bromide was used for the ring-closure reaction. Condensation of 2-hydroxy-1-naphthaldehyde with 1,6-hexamethylenediamine or 1,4-phenylenediamine gives imine compounds, which were converted to 2-hydroxynaphthylamines by reduction with NaBH4 in methanol. Ring-closure reaction between the 2-hydroxynaphthylamines and methylene bromide results in the formation of 1,3-naphthoxazine monomers M-A or M-B with good yields. The structures of the synthesized monomers were confirmed using different spectroscopic techniques (including FT-IR, 1H NMR and 13C NMR), mass spectrometry, and elemental analysis. Thermal polymerization of the monomers was investigated by FT-IR and differential scanning calorimetry (DSC). Both the 1,3-naphthoxazine monomers undergo ring-opening polymerization, leading to the formation of the corresponding polynaphthoxazines [P(M-A) and P(M-B)]. The thermal stability of the polynaphthoxazines was thereafter studied by thermogravimetric analysis (TGA).
    Za pomocą zmodyfikowanej trójetapowej syntezy, w której do reakcji zamknięcia pierścienia zastosowano bromek metylenu, otrzymano dwa nowe monomery 1,3-naftoksazyny (M-A i M-B). Kondensacja 2-hydroksy-1-naftaldehydu z 1,6-heksametylenodiaminą lub 1,4-fenylenodiaminą pozwala na wytworzenie związków iminowych, które następnie przez redukcję NaBH4 w metanolu są przekształcane w 2-hydroksynaftylaminy. Reakcja zamknięcia pierścienia pomiędzy 2-hydroksynaftylaminą i bromkiem metylenu prowadzi do utworzenia z dobrymi wydajnościami monomerów 1,3-naftoksazyny M-A i M-B. Struktury zsyntetyzowanych monomerów potwierdzono stosując różne techniki spektroskopowe, spektroskopię masową oraz analizę elementarną. Polimeryzację termiczną monomerów badano za pomącą spektroskopii w podczerwieni z transformatą Fouriera (FT-IR) i różnicowej kalorymetrii skaningowej (DSC). Oba monomery 1,3-naftoksazyny uległy polimeryzacji z otwarciem pierścienia dając odpowiednie polinaftoksazyny [P(M-A) i P(M-B)]. Za pomocą analizy termograwimetrycznej (TGA) zbadano stabilność termiczną otrzymanych polinaftoksazyn.
    Źródło:
    Polimery; 2017, 62, 2; 86-92
    0032-2725
    Pojawia się w:
    Polimery
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Anti-HIV activity of some natural phenolics
    Autorzy:
    El-Ansari, M.A.
    Ibrahim, L.F.
    Sharaf, M.
    Powiązania:
    https://bibliotekanauki.pl/articles/2049059.pdf
    Data publikacji:
    2020
    Wydawca:
    Instytut Włókien Naturalnych i Roślin Zielarskich
    Tematy:
    medicinal plants
    phenolics
    AIDS
    anti-HIV activity
    mechanism of action
    rośliny lecznicze
    związki fenolowe
    działanie anty-HIV
    mechanizm działania
    Opis:
    Acquired immunodeficiency syndrome (AIDS) is an immunosuppressive disease caused by human immunodeficiency virus (HIV). The urgent need for searching novel anti-HIV/AIDS medicines is a global concern. So far, a lot of medicinal and aromatic plants (MAPs) have been analyzed to select those that could assist in the prevention and/or amelioration of the disease. Among biologically active compounds present in these plants, one of the most promising group are phenolics. The purpose of this article was to report antiHIV activity of selected phenolic compounds of plant origin.
    Źródło:
    Herba Polonica; 2020, 66, 2; 34-43
    0018-0599
    Pojawia się w:
    Herba Polonica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect of part build orientations and sliding wear factors on tribological characteristics of FDM processed parts
    Autorzy:
    Alamro, Turki
    Yunus, Mohammed
    Alfattani, Rami
    Alnaser, Ibrahim A.
    Powiązania:
    https://bibliotekanauki.pl/articles/1845032.pdf
    Data publikacji:
    2021
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    FDM component
    ABS polymer
    tribological properties
    part developing orientation
    sliding wear
    friction
    komponent FDM
    polimer ABS
    właściwości trybologiczne
    zużycie ślizgowe
    tarcie
    Opis:
    Fused Deposition Modeling (FDM) components are commonly used for either prototypes or end products, mostly made of polymers. Polymers offer low frictional resistance to wear, so most of the engineering polymers find their increased usage in day-to-day industrial as well as domestic needs. The influence of many process controlling elements on the mechanical part properties is already being studied extensively, which demands the study of tribological characteristics like friction and wear rate under varying normal load (NL), sliding velocities (V) and part building orientations (PBO). The results showed a significant impact of the PBO and NL at various V on the tribological properties under various significant suitable sliding circumstances. Cracks were formed in the cylindrical tribometer specimens of Acrylonitrile butadiene styrene (ABS) fabricated at low PBO when operated at high NL, and V. Vertical PBO to the FDM building platform in the layers form where a number of inter-layers can bear maximum NL at higher values of V resulted in uniform wear and low frictions. Friction was noticed very low at minimum NL when PBO was 0° (horizontal) and 90° (vertical), but increased at high NL between PBO of 15° to 60°. The FDM parts improved compared to those from conventional manufacturing processes.
    Źródło:
    Archive of Mechanical Engineering; 2021, LXVIII, 3; 321-336
    0004-0738
    Pojawia się w:
    Archive of Mechanical Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Exchange rate volatility and industrial output growth in Nigeria
    Autorzy:
    Oseni, Isiaq O.
    Adekunle, Ibrahim A.
    Alabi, Mumeen O.
    Powiązania:
    https://bibliotekanauki.pl/articles/522024.pdf
    Data publikacji:
    2019
    Wydawca:
    Uniwersytet Ekonomiczny w Katowicach
    Tematy:
    Auto-Regressive Distribution Lag
    Exchange Rate Volatility
    GARCH
    Industrial output
    Nigeria
    Opis:
    Aim/purpose – This paper examines the relationship between exchange rate volatility and industrial output growth in Nigeria. In spite of the massive revenue emanating from oil wealth, Nigeria has wallowed in intergenerational poverty due to the inability to grow its industrial sector. The dilemma of exchange rate allowed growth of the industrial sector to become enormous. As such, this paper attempts a quantitative analysis of industrial output growth in Nigeria as predicted by an exchange rate volatility using a time series data from the exchange rate and the industry value added from 1986 through 2017. Design/methodology/approach – This paper adopts a quantitative analysis of exchange rate volatility as a predictor of changes in industrial output in Nigeria. Monthly Data on exchange rate from 1986 through 2017 were first analysed to show for their clustering behaviour. Thus, ascertaining whether they are volatile or not. The study employs AR(k)-EGARCH(p,q) models for the calculation of volatility in the growth rate of nominal exchange rates. Then the paper adopts the Auto-Regressive Distributed Lag Approach to account for the long-run and short-run dynamics of industrial output in Nigeria as induced by volatility in the exchange rate for different regimes under the scope. Findings – The findings reveal that the real exchange rate volatility determines industrial production as well as availability of foreign exchange increments arising from the various export drives contributing tremendously to the increase in the industrial output in Nigeria. It is further revealed that the capacity utilisation ratio was low. Research implications/limitations – Established evidence of low capacity utilisation may be due to the epileptic power supply, inadequate technological know-how. As such, the government should maintain a flexible exchange rate system to maximally harness the benefits of growth emanating from the industrial sector. Originality/value/contribution – The paper specifically offers an experimental proof to the underlying relationship between industrial output and exchange rate volatility in Nigeria. Previous studies reviewed in the literature have mostly focused on the growth effect of the exchange rate neglecting the important nexus it shares with the industrial sector (a bedrock of sustainable development).
    Źródło:
    Journal of Economics and Management; 2019, 38; 129-156
    1732-1948
    Pojawia się w:
    Journal of Economics and Management
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    In vitro culture of big-sage (Lantana camara L.) plant
    Autorzy:
    Ibrahim, M.A.
    Sabty, M.Z.
    Mussa, S.H.
    Powiązania:
    https://bibliotekanauki.pl/articles/12710538.pdf
    Data publikacji:
    2020
    Wydawca:
    Uniwersytet Przyrodniczy w Lublinie. Wydawnictwo Uniwersytetu Przyrodniczego w Lublinie
    Opis:
    The study was conducted to mass micropropagation of big sage (Lantana camara L.) plant by shoot multiplication technique. The treatments 2.22 and 2.66 µmol·L⁻¹ BA gave the highest significant increase in the percentage of response to shoot multiplication and number of shoots per explant compared to the other treatments as reached 96.70% and 100.00% and 4.33 and 6.00 shoots, respectively. The results showed that these two treatments did not differ significantly between them. While the 1.33 µmol·L⁻¹ BA gave the lowest values in the percentage of response to shoot multiplication and number of shoots per explant were 80.00% and 2.00 shoots per explant, respectively. The MS medium supplemented with 4.30 or 5.37 µmol·L⁻¹ NAA gave a high response to root formation, number of roots per shoot and root length. While the MS medium supplemented with 6.44 or 7.52 µmol·L⁻¹ NAA gave low values in these characteristics. The MS medium with 2.22 or 2.66 µmol·L⁻¹ concentration of BA or 7.52 µmol·L⁻¹ concentration of NAA recorded the highest significant increase in the percentage of response to callus formation. While the MS medium supplemented with 1.33 µmol·L⁻¹ BA or 4.30 µmol·L⁻¹ NAA gave less response to the callus formation.
    Źródło:
    Acta Scientiarum Polonorum. Hortorum Cultus; 2020, 19, 2; 67-73
    1644-0692
    Pojawia się w:
    Acta Scientiarum Polonorum. Hortorum Cultus
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Application of genetic algorithm for optimization the safety system of the nuclear reactor
    Autorzy:
    El-Sayed Wahed, M.
    Ibrahim, W. Z.
    Effat, A. M.
    Powiązania:
    https://bibliotekanauki.pl/articles/146492.pdf
    Data publikacji:
    2009
    Wydawca:
    Instytut Chemii i Techniki Jądrowej
    Tematy:
    genetic algorithm
    non-dominated sorting
    chimney water injection system (CWIS)
    Egypt nuclear
    Opis:
    The purpose of this paper is to present an approach to optimization in which every target is considered as a separate objective to be optimized. Multi-objective optimization is a powerful tool for resolving conflicting objectives in engineering design and numerous other fields. One approach to solve multi-objective optimization problems is the non-dominated sorting genetic algorithm (NSGA). Genetic algorithm (GA) was applied in regarding the choice of the time intervals for the periodic testing of the components of the chimney water injection system (CWIS) of the 22 MW open pool multipurpose reactor (MPR), ETRR-2, at the Egyptian Atomic Energy Authority, has been used as a case study.
    Źródło:
    Nukleonika; 2009, 54, 1; 51-56
    0029-5922
    1508-5791
    Pojawia się w:
    Nukleonika
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Genetic algorithms and neural networks for solving water quality model of the Egyptian research reactor
    Autorzy:
    El-Sayed Wahed, M.
    Ibrahim, W. Z.
    Effat, A. M.
    Powiązania:
    https://bibliotekanauki.pl/articles/148150.pdf
    Data publikacji:
    2009
    Wydawca:
    Instytut Chemii i Techniki Jądrowej
    Tematy:
    genetic algorithm
    neural networks
    model calibration
    water distribution system
    water quality model
    Opis:
    The second Egyptian research reactor ETRR-2 became critical on 27th November, 1997. The National Center of Nuclear Safety and Radiation Control (NCNSRC) has the responsibility for the evaluation and assessment of safety of this reactor. Modern managements of water distribution system (WDS) need water quality models that are able to accurately predict the dynamics of water quality variations within the distribution system environment. Before water quality models can be applied to solve system problems, they should be calibrated. The purpose of this paper is to present an approach which combines both macro and detailed models to optimize the water quality parameters. For an efficient search through the solution space, we use a multi-objective genetic algorithm which allows us to identify a set of Pareto optimal solutions providing the decision maker with a complete spectrum of optimal solutions with respect to the various targets. This new combinative algorithm uses the radial basis function (RBF) metamodeling as a surrogate to be optimized for the purpose of decreasing the times of time-consuming water quality simulation and can realize rapidly the calibration of pipe wall reaction coefficients of chlorine model of large-scaled WDS.
    Źródło:
    Nukleonika; 2009, 54, 4; 239-245
    0029-5922
    1508-5791
    Pojawia się w:
    Nukleonika
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Estimation of Suspended Sediment Load Using Artificial Neural Network in Khour Al Zubair Port, Iraq
    Autorzy:
    Hassan, Ayman A.
    Ibrahim, Husham T.
    Al-Aboodi, Ali H.
    Powiązania:
    https://bibliotekanauki.pl/articles/24201740.pdf
    Data publikacji:
    2023
    Wydawca:
    Polskie Towarzystwo Inżynierii Ekologicznej
    Tematy:
    suspended sediment concentration
    multilayer perceptron
    neural network
    Khour Al-Zubair port
    Basrah city
    Opis:
    The port of Khour Al-Zubair is located 60.0 km south of the city centre of Basrah; it is also located 105.0 kilometres from the northern tip of the Arabian Gulf. The main goal of this paper is to estimate the concentration of suspended deposit (SSC) in “Khour Al-Zubair” port using a Multilayer Perceptron Neural Network (MLP) based on hydraulic and local boundary parameters while also studying the effect of these parameters on estimating the SSC. Five input parameters (channel width, water depth, discharge, cross-section area, and flow velocity) are used for estimating SSC. Different input hydraulic and local boundary parameter combinations in the three sections (port center, port south, and port north) were used for creating nine models. The use of both hydraulic and local boundary parameters for SSC estimation is very important in the port area for estimating sediment loads without the need for field measurements, which require effort and time.
    Źródło:
    Journal of Ecological Engineering; 2023, 24, 6; 54--64
    2299-8993
    Pojawia się w:
    Journal of Ecological Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Flow characteristics after installation of floating bridge in open channel
    Autorzy:
    Ibrahim, Mohamed M.
    Eltoukhy, Mahmoud A.R.
    Ghanim, Adnan D.
    Powiązania:
    https://bibliotekanauki.pl/articles/1844336.pdf
    Data publikacji:
    2021
    Wydawca:
    Instytut Technologiczno-Przyrodniczy
    Tematy:
    floating bridges
    flow characteristics
    flume
    head loss
    velocity
    Opis:
    A pontoon bridge, also known as a floating bridge, can be used as for pedestrian and vehicle traffic. The buoyancy of the floating bridge limits the maximum load it can carry. This research included experimental runs to study variations of open channel flow characteristics upstream and downstream a floating bridge. Eighty one runs have been carried out using a flume in a hydraulic laboratory. The experimental run program is classified into two main categories; the first investigates the velocity ratios (vds/vus) downstream and upstream the floating bridge. The second category is concerned with the energy head losses (hL) due to the presence of a floating bridge. The experimental runs are carried out using three pontoon lengths, three flow depths, six submerged depths, and three discharges. The results are analysed and graphically presented to help predict hydraulic parameters. The outcomes have shown that the floating bridge upstream, Froude number and submergence of the pontoon are the dominant parameters that affect the studied flow characteristics.
    Źródło:
    Journal of Water and Land Development; 2021, 49; 244-251
    1429-7426
    2083-4535
    Pojawia się w:
    Journal of Water and Land Development
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Hydrometallurgical treatment of non-sulfide zinc ore for precipitation of zinc oxide nanoparticles
    Autorzy:
    Abdel-Aal, E.-S. A.
    Rashad, M. M.
    El-Shazly, A. N.
    Ibrahim, I. A.
    El-Shahat, M. F.
    Powiązania:
    https://bibliotekanauki.pl/articles/110748.pdf
    Data publikacji:
    2016
    Wydawca:
    Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
    Tematy:
    zinc ore
    sulfuric acid leaching
    filtration rate
    zinc sulfate
    zinc oxide nanoparticles
    MB photocatalytic degradation
    Opis:
    Acid leaching of Egyptian zinc ore from the Um Gheig area was carried out with sulfuric acid. This study determines the optimum conditions for dissolution of non-sulfide zinc ore. The optimum conditions are 25% -74m particle size, 45 °C temperature, 2 h leaching time, 1.1 stoichiometric molar ratio of H2SO4 to Zn, 1:3 solid/liquid ratio. The maximum filtration rate is 1.6 Mg Zn•m-2•day-1at pressure difference of 0.80 bar. The zinc recovery is about 90%. As the zinc ore contains zinc silicate, some additives were tested to enhance filtration and prevent formation of silica gel. To increase the added value of the product, zinc oxide was precipitated by a co-precipitation method in a nanosize powder with average particle size ~ 20 nm. Photocatalytic degradation of methylene blue dye under UV light using ZnO nanopowders produced at different conditions was investigated. Photocatalytic efficiency with methylene blue (MB) concentration was reduced as much as 85% in 240 min with the produced nanoparticles.
    Źródło:
    Physicochemical Problems of Mineral Processing; 2016, 52, 2; 729-737
    1643-1049
    2084-4735
    Pojawia się w:
    Physicochemical Problems of Mineral Processing
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    An empirical analysis of the impact of crude oil spot and futures prices volatility on the development of African equity markets
    ANALIZA EMPIRYCZNA WPŁYWU KRYZYSU WYDOBYCIA ROPY NAFTOWEJ I NIESTABILNOŚCI CEN TERMINOWYCH NA ROZWÓJ RYNKÓW AKCJI W KRAJACH AFRYKI
    Autorzy:
    A.O. BAKARE, Ibrahim
    O. QUADRY, Mahmud
    CHOWDHURY, Mohammad Abdul-Matin
    Powiązania:
    https://bibliotekanauki.pl/articles/434974.pdf
    Data publikacji:
    2018-03-01
    Wydawca:
    Uniwersytet Opolski
    Tematy:
    crude oil
    volatility
    equity markets
    revenue
    ropa naftowa
    ceny terminowe
    niestabilność cen
    rynki akcji
    przychody
    Opis:
    This study focused on the impact of crude oil, crude palm oil spot and futures of prices on African equity markets. It draws on daily data from January 2000 till July 2013, obtained from Bloomberg. The study employed Vector Error Correction (VEC). Findings from the econometric analysis show that there is relativity in the speed of adjustment among such countries’ equity market index as Mauritius, whose economic backbone is tourism, which responded faster compared with other ‘ equity markets. Kenya’s equity market index responded positively relative to those of Morocco and Nigeria, while South Africa’s equity market responded slowly, unlike other equity markets. The implication of Morocco and Nigeria’s equity markets adjusting slowly to the shock from crude oil market crisis was due to a high dependence of the governments of both countries on crude oil revenues in financing their economic activities. The study shows the existence of a long-term relation between crude oil, crude palm oil spot and futures prices on equity markets. The VECM Granger causality test was applied to examine the association and impact among these variables. The results indicate that crude oil spot and futures price granger influence the equity markets of Mauritius, Kenya and Morocco, while futures prices of crude oil granger impact Nigeria’s and South Africa’s equity markets.
    Praca niniejsza skupia się na wpływie jaki mają kryzys wydobycia ropy naftowej, produkcji surowego oleju palmowego oraz niestabilność cen terminowych na rynki akcji krajów afrykańskich. Autorzy analizują dane za okres od stycznia 2000 do lipca 2013, które były publikowane przez agencję Bloomberg. Wykorzystują model wektorowej korekcji błędów (VEC). Wyniki analizy ekonometrycznej wskazują, że występuje pewien związek między tempem dostosowania się wśród rynków akcji takich krajów jak Mauritius, którego podstawą gospodarki jest turystyka, i który to rynek zareagował szybciej w porównaniu z rynkami akcji innych krajów. Wskaźnik rynku akcji w Kenii kształtował się dodatnio w porównaniu z tymi w Maroko i Nigerii, podczas gdy rynek akcji w Afryce Południowej reagował wolniej, nie tak jak inne rynki akcji. Skutki wynikające dla rynków akcji w Maroko i Nigerii, które przystosowywały się wolniej do kryzysu jaki wstrząsnął rynkiem ropy, wynikały z dużego uzależnienia finansowania działalności gospodarczej od dochodów pochodzących z wydobycia ropy naftowej, jakie przyjęły rządy obu tych krajów. Badanie pokazuje istnienie długookresowego wpływu jaki wywierają niestabilny rynek wydobycia ropy naftowej, rynek surowego oleju palmowego i cen terminowych na rynki akcji. Zastosowano test VECM przyczynowości Grangera w celu zbadania związku i wpływu między tymi zmiennymi. Wyniki wskazują, że kryzys na rynku ropy naftowej oraz ceny terminowe mierzone testem Grangera wpływają na rynek akcji krajów takich jak Mauritius, Kenia i Maroko, a terminowe ceny ropy naftowej mierzone testem Grangera wpływają na rynki akcji Nigerii oraz Afryki Południowej.
    Źródło:
    Economic and Environmental Studies; 2018, 18, 1; 31-46
    1642-2597
    2081-8319
    Pojawia się w:
    Economic and Environmental Studies
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The cotton mealybug Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) as a new insect pest on tomato plants in Egypt
    Autorzy:
    Ibrahim, S.S.
    Moharum, F.A.
    Abd El-Ghany, N.M.
    Powiązania:
    https://bibliotekanauki.pl/articles/65060.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Opis:
    Recently, the mealybug Phenacoccus solenopsis Tinsley (Hemiptera: Pseudococcidae) was recorded as a new pest on tomato plants (Lycopersicon esculentum Mill) growing in Egypt. The mealybugs specimens were collected from tomato plants in the Qalyoubia governorate during summer season of 2014. The mealybug was identified as P. solenopsis based on the morphological characters and taxonomic key of this species. This study represents the first record of P. solenopsis as a new insect pest attacking tomato plants in Egypt.
    Źródło:
    Journal of Plant Protection Research; 2015, 55, 1
    1427-4345
    Pojawia się w:
    Journal of Plant Protection Research
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Determinants and adoption of West Africa Agricultural Productivity Programme (WAAPP) improved rice production technologies in Girei Local Government Area, Adamawa State, Nigeria
    Determinanty przyjęcia programu „West Africa Agric Ultural Productivity Programme” (WAAPP) – udoskonalonych technologii produkcji ryżu w Girei region samorządu lokalnego, stan Adamawa, Nigeria
    Autorzy:
    Girei, Abdulhameed A.
    Usman, Ibrahim S.
    Ogezi, E.
    Ayuba, Andeshongtso K.
    Powiązania:
    https://bibliotekanauki.pl/articles/2216453.pdf
    Data publikacji:
    2021
    Wydawca:
    Politechnika Bydgoska im. Jana i Jędrzeja Śniadeckich. Wydawnictwo PB
    Tematy:
    adoption
    agriculture
    determinants
    productivity
    programme
    rice seed
    technologies
    determinanty
    produktywność
    program
    przyjęcie
    rolnictwo
    ryż
    technologie
    Opis:
    Background. The demand for rice is increasing at this time when rice importation has been banned in Nigeria. This study investigated the Adoption of Improved West African Agricultural Productivity Programme improved rice production technologies in Girei Local Government Area of Adamawa State, Nigeria. Material and methods. Semi-structured questionnaire was used for data collection from seventy-two farmers who were randomly selected and interviewed. Results. The result showed that 85.7% of the rice farmers were male with mean age of about 42 years, 73.6% were married. The mean household size is five persons. About 18% of the respondents had no formal education; a good number of farmers adopted the improved technologies. Education level, Marital Status and Farming Experience influenced adoption of the technologies, and were positive and statistically significant at 5%. This implies that as the rice farmer increase the tendency to adopt improved technologies, their propensity to farming also increase. Double log was choosing as the lead equation and the result revealed an R2 value of 0.754, which implies that 75% variation in the adoption of WAAPP rice technologies is explained by the variables included in the model, and F ratio was also significant at 1%, indicating goodness of fit. Conclusion. Major constraints include disease and pest; scarcity and high cost of inputs; inadequate rural road network; Lack of mechanization on rice production. Efforts should be made to link farmers to agroinput dealers for adequate, quality, and timely input supplies.
    Popyt na ryż w Nigerii rośnie, a w tym samym czasie jego import został zakazany. Badanie dotyczyło wdrożenia programu poprawy wydajności rolnictwa w Afryce Zachodniej, ulepszenia technologii produkcji ryżu na obszarze samorządu lokalnego Girei w stanie Adamawa w Nigerii. Do zebrania danych wykorzystano częściowo ustrukturyzowany kwestionariusz od siedemdziesięciu dwóch rolników, których wybrano losowo i przeprowadzono z nimi wywiady. Wyniki badań wykazały, że 85,7% hodowców ryżu to mężczyźni w średnim wieku – około 42 lat, a 73,6% było w związku małżeńskim. Średnia wielkość gospodarstwa domowego to pięć osób. Około 18% respondentów nie miało formalnego wykształcenia, ale i tak wielu rolników przyjęło ulepszone technologie. Poziom wykształcenia, stan cywilny i doświadczenie rolnicze wpłynęły na przyjęcie technologii i były istotnie pozytywne na poziomie 5%. Oznaczało to, że wraz ze wzrostem przyjmowania ulepszonych technologii przez hodowców ryżu ich chęć do uprawy również wzrastała. Jako wiodące równanie wybrano Double log, a uzyskana wartość R2 = 0,754 oznacza, że 75% zmienności w przyjęciu technologii uprawy ryżu WAAPP jest zmienną zawartą w modelu. Stosunek F był również istotny na poziomie 1% i wskazywał na dobre dopasowanie. Główne ograniczenia w poprawie wydajności rolnictwa to: występowanie chorób i szkodników, wysokie koszty nakładów, nieodpowiednią sieć dróg wiejskich i brak mechanizacji w produkcji ryżu. Należy dołożyć starań, aby połączyć rolników z dostawcami środków produkcji rolnej w celu zapewnienia odpowiednich, wysokiej jakości i terminowych dostaw środków.
    Źródło:
    Acta Scientiarum Polonorum. Agricultura; 2021, 20, 1; 25-37
    1644-0625
    Pojawia się w:
    Acta Scientiarum Polonorum. Agricultura
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Structured Analysis of Nanostructured Zinc Oxide (ZnO) Thin Films Deposited by Sol-Gel
    Autorzy:
    Hussin, Rosniza
    Hanafi, F.
    Rashid, R. A.
    Harun, Z.
    Kamdi, Z.
    Ibrahim, S. A.
    Ainuddin, A. R.
    Rahman, W.
    Leman, A. M.
    Powiązania:
    https://bibliotekanauki.pl/articles/2134100.pdf
    Data publikacji:
    2022
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    sol-gel
    zinc oxide
    ZnO
    thin films
    nanostructured
    Opis:
    In this work, zinc oxide (ZnO) thin films are deposited on glass substrate using the sol-gel spin coating technique. The effect of annealing temperature on structural properties was investigated. The ZnO sol-gel was produced from zinc acetate dehydrate as the starting material with iso-propanol alcohol as the stabilizer. The ratio was controlled, distilled water and diethanolamine as the solvent mixing on a magnetic stirrer for an hour under constant heat of 60°C. The ZnO thin film was deposited using the spin coating technique with the speed of 3000 rpm for 30 minutes before the sample undergoes pre-heat in the oven at the temperature of 100°C for 10 minutes. The sample was annealing in the furnace for an hour at 200°C, 350°C, and 500°C. The X-ray diffraction (XRD) analysis confirms that hexagonal wurtzite structure with zincite and zinc acetate hydroxide hydrate composition. The thin films surface roughness was analyzed using an atomic force microscope (AFM) and scanning electron microscope (SEM) for surface morphology observation.
    Źródło:
    Archives of Metallurgy and Materials; 2022, 67, 3; 1055--1060
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Formulating delamination-fretting wear failure predictive equation in HAp coated hip arthroplasty using multiple linear regression model
    Autorzy:
    Nagentrau, M.
    Ibrahim, N.H.
    Jamian, S.
    Mohd Tobi, A.L.
    Powiązania:
    https://bibliotekanauki.pl/articles/24200558.pdf
    Data publikacji:
    2022
    Wydawca:
    Stowarzyszenie Komputerowej Nauki o Materiałach i Inżynierii Powierzchni w Gliwicach
    Tematy:
    hip arthroplasty
    delamination
    fretting
    HAp
    regression
    artroplastyka stawu biodrowego
    rozwarstwienie
    regresja
    Opis:
    Purpose: Present paper addresses the formulation of delamination-fretting wear failure predictive equation in HAp-Ti-6Al-4V interface of hip arthroplasty femoral stem component using multiple linear regression model. Design/methodology/approach: A finite element computational model utilising adaptive meshing algorithm via ABAQUS/Standard user subroutine UMESHMOTION is developed. The developed FE model is employed to examine effect of different HAp-Ti-6Al-4V interface mechanical and tribological properties on delamination-fretting wear behaviour. The FE result is utilised to formulate predictive equations for different stress ratio conditions using multiple linear regression analysis. Findings: Delamination-fretting wear predictive equations are successfully formulated with significant goodness of fit and reliability as a fast failure prediction tool in HAp coated hip arthroplasty. The robustness of predictive equations is validated as good agreement is noted with actual delamination-fretting wear results. Research limitations/implications: The influence of different mechanical and tribological properties such as delamination length, normal loading, fatigue loading, bone elastic modulus and cycle number under different stress ratio on delamination-fretting wear failure is analysed to formulate failure predictive equations. Practical implications: The formulated predictive equation can serve as a fast delamination-fretting wear failure prediction tool in hip arthroplasty femoral stem component. Originality/value: Limited attempt is done to explore the potential of utilizing multiple linear regression model to predict failures in hip arthroplasty. Thus, present study attempt to formulate delamination-fretting wear failure predictive equation in HAp -Ti-6Al-4V interface of hip arthroplasty femoral stem component using multiple linear regression model.
    Źródło:
    Archives of Materials Science and Engineering; 2022, 115, 2; 76--85
    1897-2764
    Pojawia się w:
    Archives of Materials Science and Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    An enhanced krill herd optimization technique used for classification problem
    Autorzy:
    Al-Mashhadani, Firas N.
    Alsaffar, Qusay S.
    Al-Jadir, Ibrahim A.
    Powiązania:
    https://bibliotekanauki.pl/articles/35535690.pdf
    Data publikacji:
    2021
    Wydawca:
    Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Wydawnictwo Szkoły Głównej Gospodarstwa Wiejskiego w Warszawie
    Tematy:
    optimization
    simulated annealing
    standard krill herd
    Opis:
    In this paper, this method is intended to improve the optimization of the classification problem in machine learning. The EKH as a global search optimization method, it allocates the best representation of the solution (krill individual) whereas it uses the simulated annealing (SA) to modify the generated krill individuals (each individual represents a set of bits). The test results showed that the KH outperformed other methods using the external and internal evaluation measures.
    Źródło:
    Scientific Review Engineering and Environmental Sciences; 2021, 30, 2; 354-364
    1732-9353
    Pojawia się w:
    Scientific Review Engineering and Environmental Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Space Weather: The Significance of e-CALLISTO (Malaysia) As One of Contributor of Solar Radio Burst Due To Solar Activity
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Monstein, C.
    Ibrahim, Z. A.
    Powiązania:
    https://bibliotekanauki.pl/articles/411980.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    sun
    radio emission
    solar radio burst
    Compound Astronomical Low-cost Low-frequency Instrument for Spectroscopy in Transportable Observatories (CALLISTO)
    solar flares
    Coronal Mass Ejections (CMEs)
    space weather
    Opis:
    The impact of solar activities indirectly affected the conditions of earth's climate and space weather in general. In this work, we will highlight a low cost project, however, potentially gives a high impact through a dedicated long-term and one of the most successful space weather project. This research is a part of an initiative of the United Nations together with NASA in order to support developing countries participating in „Western Science‟ research. At the beginning of 2007, the objective to monitor the solar activities (solar flares and Coronal Mass Ejections) within 24 hours all over the world has positively turned to reality. Realize how important for us to keep doing a research about the solar bursts, by using the new radio spectrometer, CALLISTO. This research is not only hoping to give a knowledge to the people about how the solar bursts are produced, the characteristics of every type of solar burst at the wide range (45 MHz to 870 MHz) but also the effect of the solar burst toward the Earth. By using the same CALLISTO spectrometer within the 45-870 MHz, designing and leading by Christian Monstein from ETH Zurich, Switzerland, this research project is the one of successful project under ISWI program. Malaysia becomes the 19th countries that involve this research. One of the advantages to start the solar monitoring in Malaysia is because our strategic location as equator country that makes possible to observing a Sun for 12 hours daily throughout a year. We strongly believe that Malaysia as one of contributor of solar activity data through E-CALLISTO network. This is a very good start for developing a radio astronomy in Malaysia.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 7; 37-44
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Complex Signal Mapping for Improving Spectral Efficiency of Li-Fi Systems
    Autorzy:
    Sileh, Ibrahim K.
    Abdulkafi, Ayad A.
    Hussein, Mohammed K.
    Hardan, Saad M.
    Powiązania:
    https://bibliotekanauki.pl/articles/958061.pdf
    Data publikacji:
    2019
    Wydawca:
    Instytut Łączności - Państwowy Instytut Badawczy
    Tematy:
    Li-Fi
    OFDM
    signal mapping
    PAPR
    BER
    Opis:
    Light fidelity (Li-Fi) systems based on the orthogonal frequency division multiplexing (OFDM) scheme have gained more attention in the communications circles, as a means to provide high spectral efficiency and ensure stricter data rate requirements for visible light communication (VLC) systems. However, common OFDM schemes employ Hermitian symmetry to obtain a real-valued signal which is necessary in intensity modulation and direct detection (IM/DD) optical systems, at the expense of doubling the required bandwidth. In this paper, a novel transmission scheme for an OFDM-based Li-Fi system is proposed to tackle the issue in question. A new approach to complex signal mapping (CSM), based on the pairing function method, has been developed for Li-Fi systems. It does not require Hermitian symmetry and, hence, saves about 50% of the required bandwidth. Unlike existing OFDM-based VLC approaches, the proposed scheme employs CSM to ensure a real and positive signal without Hermitian symmetry in order to fully utilize the bandwidth available to Li-Fi networks. Simulation results show that the proposed scheme significantly outperforms other systems in terms of spectral efficiency. The CSM-OFDM based Li-Fi system also achieves a good peak-to-average power ratio (PAPR) reduction with acceptable bit-error-rate (BER) performance, compared to conventional approaches.
    Źródło:
    Journal of Telecommunications and Information Technology; 2019, 3; 58-62
    1509-4553
    1899-8852
    Pojawia się w:
    Journal of Telecommunications and Information Technology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Estimation of technical inefficiency and production risk among small scale maize farmers in the Federal Capital Territory (FCT) Abuja, Nigeria
    Szacowanie niewydolności technicznej i ryzyka produkcyjnego wśród hodowców kukurydzy na małą skalę na Federalnym Terytorium Stołecznym Abuja, Nigeria
    Autorzy:
    Okeke, N. Immaculate
    Umar, H. Suleiman
    Girei, A. Abdulhamid
    Ibrahim, H. Yusuf
    Powiązania:
    https://bibliotekanauki.pl/articles/2216503.pdf
    Data publikacji:
    2020
    Wydawca:
    Politechnika Bydgoska im. Jana i Jędrzeja Śniadeckich. Wydawnictwo PB
    Tematy:
    consumption
    income
    maize production
    output
    dochody
    konsumpcja
    kukurydza
    produkcja
    Opis:
    Background. Estimation of technical inefficiency and Production risk play a key role in farmers’ decisions pertaining to input allocation and subsequent output. The study provided empirical evidence on technical inefficiency and associated production risk among small scale maize farmers in the Federal Capital Territory (FCT) Abuja, Nigeria. Material and methods. A multistage sampling technique was adopted in the selection of 154 respondents. Data were analyzed using descriptive statistics and a stochastic frontier function with a heteroskedastic error structure. Results. The results show that farm size and agrochemicals significantly influenced maize production at (P < 0.01) and (P < 0.1), respectively. An increasing return to scale in Maize production was observed in the study area. There was significant evidence of production risk associated with inputs used in maize production. From among the production inputs considered in the study, only seed was found to significantly reduce risk (P < 0.01). The technical inefficiency of farmers in the area ranged between 0.06-0.99 with a mean inefficiency of 0.27 (27%). Conclusion. On average 27% of the output was lost as a result of technical inefficiency in maize production and production risk could be reduced significantly if an additional quantity of maize seed is planted per hectare.
    Oszacowanie niewydolności technicznej i ryzyka produkcyjnego odgrywa kluczową rolę w decyzjach rolników dotyczących alokacji nakładów i późniejszej wydajności. Badanie dostarczyło empirycznych dowodów na nieefektywność techniczną i związane z nią ryzyko produkcyjne wśród drobnych rolników zajmujących się uprawą kukurydzy na Federalnym Terytorium Stołecznym Abudża w Nigerii. Przy wyborze 154 respondentów przyjęto wielostopniową technikę doboru próby. Dane analizowano za pomocą statystyki opisowej i stochastycznej funkcji granicznej. Wyniki pokazują, że wielkość gospodarstwa i substancje agrochemiczne znacząco wpłynęły na produkcję kukurydzy. Na badanym obszarze zaobserwowano powrót do coraz większej skali w produkcji kukurydzy. Istniały istotne dowody na ryzyko produkcyjne związane z materiałami używanymi do produkcji kukurydzy. Spośród rozważanych w badaniach nakładów produkcyjnych stwierdzono, że tylko nasiona istotnie obniżały ryzyko (P < 0,01). Nieefektywność techniczna rolników na tym obszarze wahała się między 0,06 a 0,99; średnia nieefektywność wynosiła 0,27. Średnio 27% produkcji zostało utracone w wyniku technicznej niewydolności w produkcji kukurydzy, a ryzyko produkcyjne mogłoby zostać znacznie zmniejszone, gdyby wysiano dodatkową ilość nasion kukurydzy na hektar.
    Źródło:
    Acta Scientiarum Polonorum. Agricultura; 2020, 19, 3; 147-155
    1644-0625
    Pojawia się w:
    Acta Scientiarum Polonorum. Agricultura
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The Effect of Different Processing Methods on the Behavior of Minerals Content in Food Products
    Autorzy:
    Alshallash, Khalid S.
    Shahat, Mohamed
    Ibrahim, Mohamed I.
    Hegazy, Ahmed I.
    Hamdy, Ashraf E.
    Elnaggar, Ibrahim A.
    El-Wahed, Abd El-Wahed N. Abd
    Taha, Ibrahim M.
    Powiązania:
    https://bibliotekanauki.pl/articles/24201608.pdf
    Data publikacji:
    2023
    Wydawca:
    Polskie Towarzystwo Inżynierii Ekologicznej
    Tematy:
    mineral
    fruit
    processing
    canning
    dehydration
    stewing
    Opis:
    The goal of the current study was to determine the mineral content of different fruit varieties (Na, K, Ca, P, Mg, Fe, Zn, and Cu), as well as the effects of various processing methods (such as canning, drying, stewing, syrup process, and concentration of juices). All tested fruits that were subjected to various types of processing were exposed to a degree of mineral loss, varying from very little to high reduction. However, it still retains its nutritional value. All fig products have the greatest levels of most tested minerals, compared to other processed fruit products, particularly P and Fe. In turn, orange products supply higher quantities of Ca. On the other hand, apricot products have a comparable value of other minerals with those found in fig and orange products. Among canned juices, guava had the highest contents of Ca, P, and Fe, while mango scored the first juice as Mg and Zn supplying. Canned apricot halves contain the best amounts of K, Ca, P and Mg than the same products of apple and peach. Among jam products, fig jam has higher amounts of Na, Ca, P, Mg, and Fe than those found in other fruit jams. The concentration of fruit juices by vacuum-heating or dehydration of fruit produced higher mineral retentions than the fruit products that were processed by other techniques. The concentrated orange juice by vacuum-heating processing retained most of the minerals found in raw juice, also dried apricot sheet retained higher minerals than those retained in dehydrated whole apricot.
    Źródło:
    Journal of Ecological Engineering; 2023, 24, 3; 263--275
    2299-8993
    Pojawia się w:
    Journal of Ecological Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Framework of performance measurement practices within construction companies in Egypt
    Autorzy:
    Dziekoński, K.
    Ibrahim, O. H. M. F.
    Mahamadu, A.-M.
    Manu, P.
    Powiązania:
    https://bibliotekanauki.pl/articles/125609.pdf
    Data publikacji:
    2018
    Wydawca:
    Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
    Tematy:
    performance
    measurement system
    construction
    industry
    Egypt
    wydajność
    system miar
    budowa
    przemysł
    Egipt
    Opis:
    The construction industry is considered as one of the most important sectors in Egypt. One of the major challenges faced by the industry, however, is the unavailability of suitable performance measurement systems for assessing companies’ performance. Modern performance assessment systems adopt a more universal approach to the measurement of construction company performance as opposed to the traditional project triangle. This paper aims to examine the practice of performance measurement in the Egyptian construction industry. Results show dominant role of in-house developed performance management systems as well as the use of KPIs as a method of performance assessment. The study further reveals that the highest importance is given to measures related to the time of project delivery, quality of works, clients’ satisfaction and profitability. Hence, the traditional project triangle of project’s success is the most prevalent approach to performance evaluation in the construction industry in Egypt. However, a shift towards a more holistic approach to performance assessment in larger companies was observed.
    Źródło:
    Engineering Management in Production and Services; 2018, 10, 2; 7-14
    2543-6597
    2543-912X
    Pojawia się w:
    Engineering Management in Production and Services
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Heat shock increases oxidative stress to modulate growth and physico-chemical attributes in diverse maize cultivars
    Autorzy:
    Hussain, I.
    Ashraf, M.A.
    Rasheed, R.
    Iqbal, M.
    Ibrahim, M.
    Ashraf, S.
    Powiązania:
    https://bibliotekanauki.pl/articles/25486.pdf
    Data publikacji:
    2016
    Wydawca:
    Polska Akademia Nauk. Instytut Agrofizyki PAN
    Opis:
    The present investigation was conducted to appraise the physiochemical adjustments in contrasting maize cultivars, namely, PakAfgoi (tolerant) and EV-5098 (sensitive) subjected to heat shock. Seven-day-old seedlings were exposed to heat shock for different time intervals (1, 3, 6, 24, 48 and 72 h) and data for various physiochemical attributes determined to appraise time course changes in maize. After 72 h of heat shock, the plants were grown under normal conditions for 5 d and data for different growth attributes and photosynthetic pigments recorded. Exposure to heat shock reduced growth and photosynthetic pigments in maize cultivars. The plants exposed to heat shock for up to 3 h recovered growth and photosynthetic pigments when stress was relieved. A time course rise in the relative membrane permeability, hydrogen peroxide (H2O2) and malondialdehyde contents was recorded particularly in the EV-5098 indicating that heat shock-induced oxidative stress. Activities of different enzymatic antioxidants greatly altered due to heat shock. For instance, an increase in superoxide dismutase activity was recorded in both maize cultivars. The activity of ascorbate peroxidase was greater in Pak-Afgoi. However, the peroxidase and catalase activities were higher in plants of EV-5098. Heat shock caused a significant rise in the proline and decline in the total free amino acids. Overall, the performance of Pak-Afgoi was better in terms of having lesser oxidative damage and greater cellular levels of proline. The results suggested that oxidative stress indicators (relative membrane permeability, H2O2 and malondialdehyde) and proline can be used as markers for heat shock tolerant plants.
    Źródło:
    International Agrophysics; 2016, 30, 4
    0236-8722
    Pojawia się w:
    International Agrophysics
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Medicinal plants for management and alternative therapy of common ailments in Dutsin-Ma (Katsina State) in Nigeria
    Autorzy:
    Sadoq, I.Z.
    Abubakar, F.S.
    Ibrahim, B.
    Usman, M.A.
    Kudan, Z.B.
    Powiązania:
    https://bibliotekanauki.pl/articles/2048979.pdf
    Data publikacji:
    2019
    Wydawca:
    Instytut Włókien Naturalnych i Roślin Zielarskich
    Tematy:
    ethnobotanical survey
    medicinal plants
    traditional herbalist
    common ailments
    alternative therapy
    badanie etnobotaniczne
    rośliny zielarskie
    zielarze ludowi
    typowe schorzenia
    terapia alternatywna
    Opis:
    Introduction: Nowadays, many synthetic drugs comes with various degrees of side effects, accumulative toxicity and development of resistance by microorganisms. Medicinal plants used worldwide can be developed into modern drugs with little or no side effects and greater efficacy. Objective: The aim of this paper was to document the alternative therapy used in Dutsin-Ma local community in Katsina state, Nigeria. Methods: Ethnobotanical survey was carried out among 40 traditional herbalists. Out of 106 plants found, screening was conducted to include only plants that are prescribed simultaneously by the entire herbalists. Results: We have found 32 species of medicinal plants from 20 families that are used for management and alternative therapy against common ailments such as malaria, diabetes, sickle cell anaemia, hypertension, ulcer, paralysis, typhoid fever and immune deficiency. Conclusion: Traditional medicinal plants provide the alternative therapy for treatment and management of diseases to significant number of people. Herbal practitioners are still relevant to African healthcare system.
    Źródło:
    Herba Polonica; 2019, 65, 4; 45-55
    0018-0599
    Pojawia się w:
    Herba Polonica
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Preliminary statistical analysis of anthropometrics data in related to sitting posture among college students at east coast Malaysia
    Autorzy:
    Ibrahim, M.H.
    Ishak, N.F.
    Mukhtar, N.Z.
    Basir, M.H.
    Said, N.A.
    Mohamed, K.A.
    Awang, M.E.
    Powiązania:
    https://bibliotekanauki.pl/articles/24200579.pdf
    Data publikacji:
    2022
    Wydawca:
    Stowarzyszenie Komputerowej Nauki o Materiałach i Inżynierii Powierzchni w Gliwicach
    Tematy:
    sitting posture
    anthropometric data
    human health
    pozycja siedząca
    dane antropometryczne
    zdrowie człowieka
    Opis:
    Purpose: To statistically analyse sitting posture using anthropometrics data among college students in Malaysia. Design/methodology/approach: This study was conducted among 52 college students consisting of males and females. Data were analysed using a common statistical tool which is the Statistical Package of Sosial Science (SPSS). Findings: Preliminary analysis of data indicated that there are wider differences in standard deviation of eye sitting height compared to the previous study conducted. Research limitations/implications: This study was conducted at only one higher learning institution/college located at East Cost of Malaysia. Practical implications: The larger value of standard deviation discovered as statistical analysis performed using combined data among male and female participants suggested that data should be segregated. Originality/value: Result obtained could be used as a preliminary guideline to design any related item in related to sitting posture.
    Źródło:
    Archives of Materials Science and Engineering; 2022, 116, 2; 81--85
    1897-2764
    Pojawia się w:
    Archives of Materials Science and Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Role of nutrition in the management and control of malaria infection: a review
    Autorzy:
    Onukogu, S. C.
    Ibrahim, J.
    Ogwuche, R. A.
    Jaiyeola, T. O.
    Adiaha, M. S.
    Powiązania:
    https://bibliotekanauki.pl/articles/1165192.pdf
    Data publikacji:
    2018
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Effective nutrition
    Immune system
    Malaria infection
    Malnutrition
    Poverty
    Sub-Sahara African
    Opis:
    A review of the contribution of nutrition in management and control of Malaria was conducted. Nutrition has been confirmed as one factors that can be used to suppress the effect of malaria infection before clinical treatment is received by the patient. For the body to function normally, its nutritional demand must be met in the right proportions. Diet rich in vitamins, minerals, micronutrients are required for the metabolic functioning of the body, hence effective or adequate nutrition has health benefits to the human body. Living on quality diet has a way of improving the body defense mechanism against infectious diseases such as malaria.
    Źródło:
    World Scientific News; 2018, 107; 58-71
    2392-2192
    Pojawia się w:
    World Scientific News
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Technology acceptance in learning history subject using augmented reality towards smart mobile learning environment : case in Malaysia
    Autorzy:
    Suhaimi, H.
    Aziz, N. N.
    Mior Ibrahim, E. N.
    Wan Mohd Isa, W. A. R.
    Powiązania:
    https://bibliotekanauki.pl/articles/27314247.pdf
    Data publikacji:
    2022
    Wydawca:
    Sieć Badawcza Łukasiewicz - Przemysłowy Instytut Automatyki i Pomiarów
    Tematy:
    smart city education
    mobile learning
    augmented reality
    history
    technology acceptance model
    Opis:
    In alignment with smart city initiatives, Malaysia is shifting its educational landscape to a smart learning environment. The Ministry of Education (MoE) has made History a mandatory subject for passing the Malaysian Certificate of Education to grow awareness and instil patriotism among Malaysian students. However, History has been known as one of the difficult subjects to study for many students. On the other hand, the Malaysian Government Education Blueprint 2013-2025 seeks to “leverage ICT scale up quality learning” across the country. Therefore, this study aims to identify the factors that influence the intention to use Augmented Reality (AR) for mobile learning in learning History subject among secondary school students in Malaysia. Quantitative approach has been chosen as the research method for this study. A direct survey was conducted on 400 secondary school students in one of the smart cities in Malaysia as the target respondents. The collected data are analysed through descriptive statistics and Multiple Linear Regression analysis by using Statistical Package for the Social Sciences. Based on the results, the identified factors that influence the intention to use AR for mobile learning in learning History subject are Gender, Perceived Usefulness, Perceived Enjoyment, and Attitude Towards Use. The identified factors can be a good reference for schools and teachers to strategize their teaching and learning methods in pertaining to History subject among secondary school students in Malaysia. Future studies may include the study of various types of schools in Malaysia and explore more moderating effects of demographic factors.
    Źródło:
    Journal of Automation Mobile Robotics and Intelligent Systems; 2022, 16, 2; 20--29
    1897-8649
    2080-2145
    Pojawia się w:
    Journal of Automation Mobile Robotics and Intelligent Systems
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Investigation on a Broken Solar Burst Type II during High Activities in AR1613 on 13th November 2012
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Monstein, C.
    Zulkifli, W. N. A. W.
    Ibrahim, M. B.
    Arifin, N. S.
    Amran, N. A.
    Powiązania:
    https://bibliotekanauki.pl/articles/411666.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    sun
    low frequency
    solar radio
    burst
    type II
    type III
    e-CALLISTO
    Opis:
    The present article is an attempt to analyze the solar burst Type II observations based on solar flare and Coronal Mass Ejections (CMEs) events. We choose an intriguing type II radio burst with a velocity of 1193 kms-1 that occurred on 2012 November 13 at 2:04:20 UT. In this case, the study of solar radio burst type III is of paramount importance because of the fact that it helps to gain an insight of generation mechanisms of solar flare and Coronal Mass Ejections (CMEs) phenomena. Here, we have got a reasonably clear idea of the various forms under which the type III continuum emission may appear and potentially form a type II burst. However, in this case, the Type II solar burst only successfully forms a fundamental structure within the first few minute period, but broken suddenly before evolve a harmonic structure. This phenomenon is very interesting to be tackled and study. How the burst suddenly broken is still ongoing research seems the event is very rare and hard to be proved. There are a few questions that cause this unique situation which related to: (i) the intensity and duration of type III burst which also related to the classification of solar flare (ii) the probabilities CMEs to occur during that time and also the factor of the total amount of massive burst that exploded, Thus, we can conclude that the solar burst type III event still tells us an enigmatic characteristic from time to time due to the relationship of energetic particles and streams of particles with coronal magnetic fields and the pattern of Sun activity due to the 24th solar cycle. It might an interesting to study in detail the main factor that caused the Type II solar burst broken. Indirectly, it might because of the very intense of solar flares that make the percentage of energy of solar flare become more dominant rather than the acceleration of particles through the Coronal Mass Ejections. Thus, we realize that the potential energy during this event is higher than the kinetic energy of the particles.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 9; 8-15
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Observation of the Radio Frequency Interference (RFI) at the National Space Centre, Malaysia
    Autorzy:
    Hamidi, Z.S.
    Shariff, N.N.M.
    Monstein, C.
    Wan Zulkifli, W.N.A.
    Ibrahim, M.B.
    Arifin, N.S.
    Amran, N.A.
    Powiązania:
    https://bibliotekanauki.pl/articles/11076.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    observation
    Radio Frequency Interference
    National Space Centre
    Sun
    astronomy
    solar monitoring
    e-CALLISTO system
    Malaysia
    Opis:
    Important results of the Radio Frequencies Interference (RFI) at the National Space Centre, Sg Lang Selangor, Malaysia has been reported. In order to make sure that the data of solar monitoring in radio region is reliable, we need to study the variation of interference and the possible sources that contribute to this interference. This data has been taken from 1-2000 MHz at the main site of installation e-CALLISTO system. The study is one of a main part of an initiative of e-CALLISTO networking research in order to identify the main RFI sources and to monitor continuously the behavior of the RFI at the site. Our main objective is to qualify the potential of monitoring a continuous radio emission of the Sun. This work is also an initiative of the International Space Weather Initiative (ISWI) project where Malaysia is one of the countries that joined the e-CALLISTO network. Due to our results this site showed the positive impact for the solar monitoring purpose. It is hoped that the survey will continue from time to time in a consistent mode so that any polluted signal for radio astronomy purpose can be protected. Overall, we can still get a good solar burst data, especially at 40-400 MHz. Perhaps, we can contribute the good data for solar burst monitoring towards the maximum cycle beginning the end of this year 2013.
    Źródło:
    International Letters of Natural Sciences; 2014, 05
    2300-9675
    Pojawia się w:
    International Letters of Natural Sciences
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Simultaneous Adsorption of Ternary Antibiotics (Levofloxacin, Meropenem, and Tetracycline) by SunFlower Husk Coated with Copper Oxide Nanoparticles
    Autorzy:
    Ibrahim, Mohammed A.
    Shaban, Mohammed Ali A.
    Hasan, Yaseen Rashid
    M-Ridha, Mohanad J.
    Hussein, Haitham A.
    Abed, Khalid M.
    Mohammed, Sabah J.
    Muhamad, Mohd Hafizuddin
    Hasan, Hassimi Abu
    Powiązania:
    https://bibliotekanauki.pl/articles/2105287.pdf
    Data publikacji:
    2022
    Wydawca:
    Polskie Towarzystwo Inżynierii Ekologicznej
    Tematy:
    adsorption
    antibiotics
    neural network
    wastewater
    sustainable process
    Opis:
    In this study, a new adsorbent derived from sunflower husk powder and coated in CuO nanoparticles (CSFH) was investigated to evaluate the simultaneous adsorption of Levofloxacin (LEV), Meropenem (MER), and Tetracycline (TEC) from an aqueous solution. Significant improvements in the adsorption capacity of the sunflower husk were identified after the powder particles had been coated in CuO nanoparticles. Kinetic data were correlated using a pseudo-second-order model, and was successful for the three antibiotics. Moreover, high compatibility was identified between the LEV, MER, and TEC, isotherm data, and the Langmuir model, which produced a better fit to suit the isotherm curves. In addition, the spontaneous and exothermic nature of the adsorption process was crucial for transforming the three antibiotics into CSFH. The greatest CSFH adsorption capacity was in MER (131.83 mg/g), followed by TEC (96.95 mg/g), and LEV (62.24 mg/g). These findings thus indicate that CSFH is one of the most effective and efficient adsorbents to use for eliminating wastewater contaminated with antibiotic residue.
    Źródło:
    Journal of Ecological Engineering; 2022, 23, 6; 30--42
    2299-8993
    Pojawia się w:
    Journal of Ecological Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Characterization of a molybdenum-reducing bacterium with the ability to degrade phenol, isolated in soils from Egypt
    Autorzy:
    Ibrahim, Y.
    Abdel-Mongy, M.
    Shukor, M.S.
    Hussein, S.
    Ling, A.P.K.
    Shukor, M.Y.
    Powiązania:
    https://bibliotekanauki.pl/articles/80115.pdf
    Data publikacji:
    2015
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    molybdenum
    molybdenum-reducing bacteria
    contaminated soil
    bioremediation
    nonylphenol
    phenol
    Egypt
    Źródło:
    BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology; 2015, 96, 3
    0860-7796
    Pojawia się w:
    BioTechnologia. Journal of Biotechnology Computational Biology and Bionanotechnology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    An X-ray Observations of A Gradual Coronal Mass Ejections (CMEs) on 15th April 2012
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Monstein, C.
    Wan Zulkifli, W. N. A.
    Ibrahim, M. B.
    Arifin, N. S.
    Amran, N. A.
    Powiązania:
    https://bibliotekanauki.pl/articles/411850.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    Sun Coronal Mass Ejections (CMEs)
    solar corona
    solar flare
    solar cycle
    Opis:
    In the present work, we will highlight the solar observation during 15th April 2012, solar filament eruption which is accompanied by an intense and gradual Coronal Mass Ejections (CMEs) The explosion of CMEs was observed at 2:12:06 UT and also can be observed by the Solar Dynamics Observatory (SDO) with an Active Region AR1458 is crackling with C-class solar flares. The solar flare class B3 and C2 were observed beginning 2241 UT and 0142 UT. The event is considered as second largest CMEs been detected since five years. Although the solar activity within a few days is considered quite low and there are no proton events were observed at geosynchronous orbit., the is still an unexpected explosion of CMEs can be occurred. The radio flux number (10.7 cm) exceeds 102 with the number of sunspot and area of sunspot increased to 77 and 270. The velocity of CMEs was calculated based on the LASCO2 data. From the results, it is clearly seen that the range of the velocity is between 200 kms-1 to 2000 kms-1. This wide of range proved that the mechanism of the CMEs is a gradual process. The explosion of CMEs velocity is located from 80º - 255º from North of the Sun. We can then conclude that currently, the rearrangement of the magnetic field, and solar flares may result in the formation of a shock that accelerates particles ahead of the CMEs loop and an active region play an important character in this event.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 8; 13-19
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Logistical Advantages Due to the Use of an Innovative Sensor Unit for Controlling Optimum Biogas Processes
    Autorzy:
    Schlegel, M.
    Fras, J.
    Geick, T.
    Zosel, J.
    Schelter, M.
    Kritzner, A.
    Orth, M.
    Ibrahim, B.
    Kanswohl, N.
    Powiązania:
    https://bibliotekanauki.pl/articles/409594.pdf
    Data publikacji:
    2016
    Wydawca:
    Politechnika Poznańska. Wydawnictwo Politechniki Poznańskiej
    Tematy:
    remote control
    biogas process
    sensor unit
    Opis:
    For imaging of the biogas process fast and long-term stable measurement methods misses for certain parts of the process. Thus, it is necessary to know the development of organic acids. These metabolites, which are generated during the bacterial degradation, are important indicators. The process is generally very confusing, not only in terms of the number of occurring bacteria and chemical compounds, but also their variabilities. For the knowledge of such changes a direct, low-wear and permanent monitoring of organic acids would be extremely useful. Upon the occurrence of a change like hyperacidity we could react quickly. There are already some proven methods. However, these methods have several disadvantages: the information gathering is logistically difficult by long journeys, by process conditions information’s are delayed and distorted, quickly worn sensors, etc. Therefore, a innovative development is presented here, which avoids all the disadvantages listed. The sensor unit has been developed in cooperation with KSI Meinberg, Logic Way Schwerin, IBZ Hohen Luckow, University of Rostock and a polish colleague. According to Raoult law a characteristic is used in principle, which is typical of some liquid and gaseous media that are touching. This means volatile substances, which for example, are also in the fermenter broth, among others organic acids, are also detectable in the gaseous phase. If in the gas phase such acids can be detected, conclusions about the acid content in the substrate broth are possible. In different experiments evaluable matches between the developments of organic acids on the one hand in the liquid phase (broth) and on the other hand, in the gaseous phase were found. These results are based on an acid sensor unit with which distant standing biogas plants can be controlled remotely. A project regarding this topic is supported by research programme ZIM. Project executing organization is AiF (Arbeitsgemeinschaft industrieller Forschungsvereinigungen “Otto von Guericke” e.V.).
    Źródło:
    Research in Logistics & Production; 2016, 6, 5; 407-418
    2083-4942
    2083-4950
    Pojawia się w:
    Research in Logistics & Production
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    MANGO GINGER SUPPLEMENTATION MAY PROTECT BONE DAMAGE INDUCED BY METHOTREXATE IN RATS
    Autorzy:
    Sahin, Kazim
    Erten, Fusun
    Tuzcu, Mehmet
    Orhan, Cemal
    Ozercan, Ibrahim H.
    Balci, Tansel A.
    Tuzcu, Zeynep
    Juturu, Vijaya
    Powiązania:
    https://bibliotekanauki.pl/articles/895555.pdf
    Data publikacji:
    2019-04-30
    Wydawca:
    Polskie Towarzystwo Farmaceutyczne
    Tematy:
    methotrexate
    bone mineral density
    mango ginger
    Opis:
    Mango ginger (MG) has antiinflammatory and antioxidant properties. The objective of this study was to investigate the potential protective role of MG and the mechanisms against methotrexate (MTX) induced bone damage in rats. A total of 28 Sprague-Dawley rats were divided into four groups: i) control; ii) MG, rats were treated orally with 50 mg/kg/day of MG, iii) MTX, rats were injected with 0.75 mg/kg of MTX from 8th to 12th day for 5 days and iv) MTX+MG group, rats were treated with 50 mg/kg/day of MG and injected with MTX from 8th to 12th day for 5 days. MTX pretreatment increased blood urea nitrogen and creatinine levels and aminotransferase enzyme activities, while tibia osteocalcin levels and bone mineral density (BMD) decreased (p < 0.001). MG pretreatment markedly attenuated aminotransferases activities and creatinine levels and increased tibia osteocalcin levels and femur BMD in the MTX + MG groups. MTX treatment increased levels of bone nuclear factor kappa beta ligand receptor-activator (RANKL), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) and decreased the bone osteoprotegerin (OPG) and type1 collagen levels (p < 0.001). The effect of MG treatment on RANKL, IL-6, TNF-α, OPG and type1 collagen levels induced by MTX was observed actual effects (p < 0.05). Similarly, the protective effect of MG against MTX was confirmed by histological examination. In conclusion, MG pretreatment reduced the negative effects of MTX on bone damage by improving BMD and modulation of RANKL, IL-6, TNF-α, OPG and type1 collagen expressions in the rats.
    Źródło:
    Acta Poloniae Pharmaceutica - Drug Research; 2019, 76, 2; 305-312
    0001-6837
    2353-5288
    Pojawia się w:
    Acta Poloniae Pharmaceutica - Drug Research
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Degradation and physical properties of sugar palm starch/ sugar palm nanofibrillated cellulose bionanocomposite
    Degradacja i właściwości fizyczne bionanokompozytów skrobi palmy cukrowej wzmocnionej nanowłóknami celulozowymi tej palmy
    Autorzy:
    Atikah, M. S. N.
    Ilyas, R. A.
    Sapuan, S. M.
    Ishak, M. R.
    Zainudin, E. S.
    Ibrahim, R.
    Atiqah, A.
    Ansari, M. N. M.
    Jumaidin, R.
    Powiązania:
    https://bibliotekanauki.pl/articles/947563.pdf
    Data publikacji:
    2019
    Wydawca:
    Sieć Badawcza Łukasiewicz - Instytut Chemii Przemysłowej
    Tematy:
    sugar palm
    high pressurized homogenizer
    nanofibrillated cellulose
    nanocomposites
    soil burial degradation
    palma cukrowa
    homogenizacja wysokociśnieniowa
    nanowłóknista celuloza
    nanokompozyty
    degradacja w glebie
    Opis:
    This paper aims to study the degradation rate of sugar palm nanofibrillated cellulose (SPNFCs) and sugar palm starch (SPS). SPNFCs were isolated from sugar palm fiber, while SPS is extracted from sugar palm trunk. The SPNFCs were reinforced with SPS biopolymer as biodegradable reinforcement materials of different diameter/length based on the number of passes of high pressurize homogenization process (5, 10 and 15 passes represented by SPS/SPNFCs-5, SPS/SPNFCs-10, and SPS/SPNFCs-15). These SPNFCs were incorporated into SPS plasticized with glycerol and sorbitol via solution casting method. Soil burial experiment performed on SPS and SPS/SPNFCs bionanocomposites showed that SPS was degraded more rapidly by losing 85.76% of its mass in 9 days compared to 69.89% by SPS/SPNFCs-15 bionanocomposite. The high compatibility between SPNFCs nanofiber and SPS biopolymer matrices can be observed through field emission scanning electron microscopy (FE-SEM).
    Zbadano szybkość degradacji nanowłóknistej celulozy wyizolowanej z palmy cukrowej (Arenga pinnata) (SPNFCs) oraz skrobi wydzielonej przez ekstrakcję z rdzenia pnia tej palmy (SPS). SPNFCs uzyskiwano z włókien palmy cukrowej, poddawanych homogenizacji pod wysokim ciśnieniem w 5, 10 lub 15 cyklach, otrzymując nanowłókna celulozy o różnej długości i średnicy. SPNFCs wprowadzano do SPS uplastycznionego mieszaniną (1 : 1) glicerolu isorbitolu. Metodą odlewania z roztworu wytwarzano błony nanokompozytowe SPS/SPNFCs-5, SPS/SPNFCs-10 i SPS/SPNFCs-15. Test glebowy procesu biodegradacji wykazał, że SPS ulegało szybszej degradacji, tracąc 85,76% swojej masy w ciągu 9 dni, w porównaniu z ubytkiem masy 69,89% w wypadku bionanokompozytu SPS/SPNFCs-15. Na podstawie analizy metodą skaningowej mikroskopii elektronowej z emisją polową (FE-SEM) stwierdzono dużą kompatybilność między nanowłóknami SPNFCs i biopolimerową osnową SPS.
    Źródło:
    Polimery; 2019, 64, 10; 680-689
    0032-2725
    Pojawia się w:
    Polimery
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    The Correlation between Solar Flare Phenomena in an X-ray Region and Radio Flux Measurement from January to September 2010
    Autorzy:
    Hamidi, Z. S.
    Shariff, N. N. M.
    Ali, M. F.
    Monstein, C.
    Zulkifli, W. N. A. W.
    Ibrahim, M. B.
    Arifin, N. S.
    Amran, N. A.
    Powiązania:
    https://bibliotekanauki.pl/articles/411743.pdf
    Data publikacji:
    2014
    Wydawca:
    Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
    Tematy:
    sun
    chromospheres
    flares
    radio flux
    solar activity
    Opis:
    A short term variation of solar flare in nine months (January 2010 to September 2010) is presented. This paper review and analyze the correlation between radio flux strength measurement and solar flare in the X-ray region. The radio flux measurement data were taken from the National Research Council; Ottawa while hard X-ray emission observed by Royal Observatory of Belgium. The overall range of solar radio flux recorded in this study ranging from 68 x 10-22 Wm-2Hz-1 to 96 x 10-22 Wm-2Hz-1. As there was no class of an X of solar flare reported at all in this study, we can confirm that there are no major effects that happened on Earth and outer space such as Coronal Mass Ejections (CMEs) and solar storms. We concluded that the Sun shows a very minimum activity towards 24th solar cycle.
    Źródło:
    International Letters of Chemistry, Physics and Astronomy; 2014, 9; 84-92
    2299-3843
    Pojawia się w:
    International Letters of Chemistry, Physics and Astronomy
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Effect of a Subjective Grading System and Blending with Polyester on Selected Wool and Yarn Characteristics of Subtropical Egyptian Barki Sheep
    Ocena właściwości przędz mieszanych wełna/poliester
    Autorzy:
    Helal, Ahmed
    Agamy, Rania
    Gad Allah, Aymen A. I.
    Al-Betar, Essam M.
    Mahouda, Sabry F.
    Abdel-Mageed, Ibrahim I.
    Powiązania:
    https://bibliotekanauki.pl/articles/232691.pdf
    Data publikacji:
    2019
    Wydawca:
    Sieć Badawcza Łukasiewicz - Instytut Biopolimerów i Włókien Chemicznych
    Tematy:
    wool
    yarn
    strength
    elongation
    friction
    polyester blends
    wełna
    przędza
    wytrzymałość
    wydłużenie
    tarcie
    mieszanka wełna-poliester
    Opis:
    Seven-hundred kilograms of subtropical Barki wool was collected to study the effect of a subjective grading system and blending with polyester on selected wool and yarn characteristics. Wool was graded subjectively into coarse, fine and raw; then each grade was blended with 0%, 15%, 25%, 35% and 45% of polyester. Staple and yarn strengths were higher in both coarse and fine grades compared with raw wool. Staple elongation of the fine grade reached 3 times that of coarse grade and twice as much as raw grade. Also, in the 100% wool blend, yarn elongation of the fine grade was twice as much as both coarse and raw grades. The fine grade had the highest yarn friction, followed by other grades. Generally, adding polyester to coarse and fine grades led to an improved yarn strength compared with the raw grade. Adding 15% polyester caused the highest improvement among other percentages. Correlations among traits were also discussed.
    Do badań wykorzystano 700 kg wełny. Dokonano oceny wybranych właściwości wełny i przędz mieszanych wełna/poliester. Wełna była oceniana subiektywnie na grubą, cienką i surową; następnie każdy gatunek został zmieszany z 0%, 15%, 25%, 35% i 45% poliestru. Zbadano wytrzymałość, wydłużenie i współczynnik tarcia przędz. Stwierdzono, że, dodawanie poliestru do grubych i cienkich włókien wełnianych prowadziło do polepszenia wytrzymałości przędz w porównaniu do przędz z włókien surowych. Największą poprawę właściwości spowodowało dodanie 15% poliestru. Omówiono również korelacje między cechami.
    Źródło:
    Fibres & Textiles in Eastern Europe; 2019, 5 (137); 23-27
    1230-3666
    2300-7354
    Pojawia się w:
    Fibres & Textiles in Eastern Europe
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Extraction of Tannic Acid from Kenaf Bast Fibre using Ultrasonic Assisted Extraction
    Autorzy:
    Mohamad, Mardawani
    Ibrahim, H. A.
    Nasir, M. F. M.
    Mohidem, Nur Atikah
    Shoparwe, N. F.
    Teo, Pao Ter
    Masri, Mohamad Najmi
    Irfan, Abd Rahim
    Powiązania:
    https://bibliotekanauki.pl/articles/2134102.pdf
    Data publikacji:
    2022
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    ultrasonic assisted extraction
    UAE
    sonication time
    duty cycle
    extraction process
    kenaf bast fibre
    Opis:
    Tannic acid or tannin, type of phenolic compound contains in kenaf bast fibre. Conventional extraction has certain limitations in terms of time, energy, and solvent consumption. Ultrasound assisted extraction (UAE) can extract bioactive components in shorter time, low temperature, with lesser energy and solvent requirement. UAE as alternative extraction technique is better equipped to retain the functionality of the bioactive compounds. In this study, the conditions for ultrasound assisted extraction (UAE) of tannic acid from kenaf bast fibre by assessing the effect of sonication time and different duty cycles were optimized. The use of ultrasound to extract tannic acid from kenaf bast fiber was evaluated. Ultrasound-assisted extraction (UAE) was carried out using ethanol as solvent to intensify the extraction efficacy. Phytochemical screening was conducted to identify the presence of tannic acid in extracts. The extracts then were analyzed using High-Performance Liquid Chromatography (HPLC) and Scanning Electron Microscopy (SEM). It was found that 0.2429 mg/mL of tannic acid was obtained under the extraction conditions of extraction temperature of 40℃, sonication time of 20 minutes and duty cycle of 50%. From SEM analysis, it was found that the raw sample demonstrated rough surface and no porous but kenaf bast fibre display smoother surface with less impurities and few pores appeared after the extraction process using UAE. These results indicate that ultrasound-assisted extraction is an efficient method for extracting tannic acid from kenaf bast fibre with the advantages of lower extraction time and higher extraction yield.
    Źródło:
    Archives of Metallurgy and Materials; 2022, 67, 3; 1061--1066
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Removal of Cadmium using Alkaline-Treated Activated Carbon from Leucaena Leucocephala Biomass
    Autorzy:
    Ibrahim, W. M. H. W.
    Sulaiman, Nurul Syuhada
    Amini, Mohd Hazim Mohammad
    Kadir, W. R. A.
    Mohamed, Mazlan
    Ramle, Sitti Fatimah Mhd
    Bilgin, Ugur
    Rahman, Wan
    Powiązania:
    https://bibliotekanauki.pl/articles/2125550.pdf
    Data publikacji:
    2022
    Wydawca:
    Polska Akademia Nauk. Czytelnia Czasopism PAN
    Tematy:
    activated carbon
    cadmium
    Leucaena leucocephala
    adsorption
    Opis:
    Water contamination that caused by heavy metals is a very common phenomenon in the industrial age. One of the popular way to treat metal contaminated water is by adsorption process using activated carbon as the adsorbent. This paper works on producing activated carbon by chemical means with impregnation ratios of NaOH:char (w/w) was predetermined at 1:1 (ACT1-1), 2:1 (ACT2-1) and 3:1 (ACT3-1) under activation temperature of 700°C. Considering the Leucaena leucocephala is a wildly, easy and fast grown species, with the availability throught the year, it was chosen to be used as the precursor. The properties of these activated carbons and its potential for cadmium removal from aqueus solution was analyzed. It was found that the highest surface area was recorded at 662.76 m²/g. Four parameters were studied which are contact time, the effect of pH, initial concentration of adsorbate and temperature. The equilibrium time was achieved in 40 min treatment at initial concentrations of 30 mg/l. The adsorbent exhibited good sorption potential for cadmium at pH 8.0 and equilibrium temperature of 30℃. Based on the results, this study had proved that activated carbon from Leucaena leucocephala biomass have the good potential to be used for removal of cadmium from wastewater.
    Źródło:
    Archives of Metallurgy and Materials; 2022, 67, 3; 1033--1036
    1733-3490
    Pojawia się w:
    Archives of Metallurgy and Materials
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Bee Pollen as a Functional Product – Chemical Constituents and Nutritional Properties
    Autorzy:
    Alshallash, Khalid S.
    Abolaban, Gomaa
    Elhamamsy, Sam M.
    Zaghlool, Ayman
    Nasr, Ali
    Nagib, Ashraf
    Abd El-Hakim, Ahmed F.
    Zahra, Abdullah A.
    Hamdy, Ashraf E.
    Taha, Ibrahim M.
    Powiązania:
    https://bibliotekanauki.pl/articles/2202357.pdf
    Data publikacji:
    2023
    Wydawca:
    Polskie Towarzystwo Inżynierii Ekologicznej
    Tematy:
    eucalyptus
    clover
    maize
    phenolic content
    amino acid
    pollen
    Opis:
    Nutritional supplements play a role in promoting human protein synthesis, fitness recovery, and mental health protection. Pollen is considered a natural food with excellent nutritional value. The use of bee-gathered pollen as a nutritional supplement is now widespread around the world, and it is appreciated for its healing qualities. However, depending on the floral species and the region of origin, pollen has a wide range of nutritional value. It was found that clover pollen had the highest protein content (31.4 g/100 g DM), while the lowest content was observed in maize pollen (21.3%). Eucalyptus pollen had the highest lipid amount (9.49 g/100 g DM), while clover pollen had the lowest content (7.46 g/100 g). Phytochemical analysis showed that eucalyptus pollen occupied the highest total antioxidant activity (67.02%), followed by clover (58.25%) then maize (52.18%), whereas clover pollen had the highest phenolic content (1165 mg GAE/100 gm), compared with the other pollen varieties (949.4 to 1073 mg-GAE/100 gm). The contents of branched-chain amino acids were 29, 33.3, and 38.4 mg/g for maize, eucalyptus, and clover respectively, representing 17.87, 18.44, and 16.53% of total amino acids. The contents of total essential amino acids (EAAs) were 61.8, 73.0, and 83.5 mg/g for maize, eucalyptus, and clover pollen, respectively. Only eucalyptus pollen ultimately met the minimum requirements of EAAs for adults. In contrast, the other two types of pollen contained at least 3–4 limiting amounts of the essential amino acids leucine, lysine, phenylalanine, and valine. In conclusion, pollen is a good, affordable source of nutrients that can be utilized as beneficial dietary supplements for human health.
    Źródło:
    Journal of Ecological Engineering; 2023, 24, 2; 173--183
    2299-8993
    Pojawia się w:
    Journal of Ecological Engineering
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
    Tytuł:
    Evaluating the Total Phenolic, Protein Contents, Antioxidant and Pharmacological Effects of Cynodon dactylon Extracts Against Escherichia coli and Staphylococcus aureus
    Autorzy:
    Ibrahim, Muhammad
    Riaz, Moazama
    Ali, Akbar
    Shaheen, Musarat
    ur Rahman, Shafiq
    Aziz, Riffat
    Alamri, Abdulhakeem S.
    Alhomrani, Majid
    Dablool, Anas S.
    Alghamdi, Saad
    Sameeh, Manal Y.
    Tashkandi, Manal A.
    Powiązania:
    https://bibliotekanauki.pl/articles/27315658.pdf
    Data publikacji:
    2023
    Wydawca:
    Zachodniopomorski Uniwersytet Technologiczny w Szczecinie. Wydawnictwo Uczelniane ZUT w Szczecinie
    Tematy:
    Cynodon dactylon
    Anti-microbial
    Flavonoids
    Total Soluble Proteins
    Peroxidase
    Antioxidant
    Super oxide Dismutase
    Opis:
    The study was aimed to characterize the antioxidant and anti-microbial activities of Cynodon dactylon with special reference on its precise biochemical analysis. Physiological analysis that total carotenoids content (0.3884 ± 0.0172 mg/g), total chlorophyll content (6.1460 ± 0.2915 mg/g), total phenolic contents (13.4703 ± 0.1494 mg/g), chlorophyll a (3.7708 ± 0.1528 mg/g, catalase (CAT) contents (40.2844 ± 0.1515 units/ mg), total anthocyanin contents (5.0166 ± 0.2966 g–1 FW) total soluble proteins (2.9916 ± 0.1734 mg/g) and total flavonoids content (TFC) (4.7863 ± 0.0442 μg/g) was found higher in the leaves of the Cynodon dactylon whereas, chlorophyll b (2.4881 ± 0.1326 mg/g) was found higher in the stem of Cynodon dactylon, while, peroxidase (POD) contents (81.8763 ± 4.6609 units/mg) and superoxidase dismutase (SOD) activity (80.4346 ± 5.9367 units/mg) was investigated higher in roots of Cynodon dactylon. The anti-microbial activity of Cynodon dactylon extracts was performed using a good diffusion technique against two microbial strains. Among all the plant extracts, the methanolic extracts showed a maximum inhibition zone (26.87 mm) against anti-bacterial strain Escherichia coli whereas n-hexane extract showed a maximum inhibition zone (17.88 mm) against anti-fungal strain Candida albicans. This study reported the antimicrobial activity of Cynodon dactylon against some common pathogens such as Staphylococcus aureus, Escherichia coli, and Candida albicans, which are highly associated with nosocomial infection. From the given results it is concluded that Cynodon dactylon could be exploited in pharmacology due to its antioxidant and anti-microbial properties.
    Źródło:
    Polish Journal of Chemical Technology; 2023, 25, 3; 110--119
    1509-8117
    1899-4741
    Pojawia się w:
    Polish Journal of Chemical Technology
    Dostawca treści:
    Biblioteka Nauki
    Artykuł
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