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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:
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:
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:
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:
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:
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:
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:
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:
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:
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:
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:
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:
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:
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:
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
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