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Wyszukujesz frazę "Mohamed, A." wg kryterium: Autor


Tytuł:
Study of big Movement of Temporary Sheet Pile in Elatf Power plant North of Egypt using Finite Element Analysis
Autorzy:
Mohamed, A. A.
Powiązania:
https://bibliotekanauki.pl/articles/115733.pdf
Data publikacji:
2014
Wydawca:
Fundacja na Rzecz Młodych Naukowców
Tematy:
finite element analysis
sheet pile
soil profile
3D analysis
2D analysis
Opis:
The failure of sheet pile walls used for temporary works may cause loss of project construction time and money. The failure can be due to lack of knowledge about the soil conditions or a requirement of three dimension analysis, as it may be important for some cases. In this paper a study was made for a big movement during temporary excavation works using sheet pile walls. A back analysis was made using three and two dimensional finite element analysis as well as simple manual calculation in order to find out the causes of the big movement. The results from the analysis was represented and compared with field data and observation. The results from the two dimensional analysis showed higher values than that from three dimensional analysis and both indicated lower results than that from field observation. However the wall movement values deduced from F.E. indicated possible failure. The performed simple manual calculation indicated also failure. The general conclusion was considered that the failure was due to design mistake.
Źródło:
Challenges of Modern Technology; 2014, 5, 1; 28-33
2082-2863
2353-4419
Pojawia się w:
Challenges of Modern Technology
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new BEM for modeling and simulation of 3T MDD laser-generated ultrasound stress waves in FGA smart materials
Autorzy:
Fahmy, Mohamed A.
Powiązania:
https://bibliotekanauki.pl/articles/29520102.pdf
Data publikacji:
2021
Wydawca:
Akademia Górniczo-Hutnicza im. Stanisława Staszica w Krakowie. Wydawnictwo AGH
Tematy:
oundary element method
modeling and simulation
three-temperature
memory-dependent derivative
laser ultrasonic
nonlinear thermal stress waves
functionally graded anisotropic
smart materials
Opis:
The goal of this study is to present a new theory known as the three-temperature memory-dependent derivative (MDD) of ultrasound stress waves in functionally graded anisotropic (FGA) smart materials. It is extremely difficult to address the difficulties related to this theory analytically due to its severe nonlinearity. As a result, we suggest a new boundary element method (BEM) to solve such equations. The suggested BEM technique incorporates the benefits of both continuous and discrete descriptions. The numerical results are visually represented to demonstrate the impacts of MDD three temperatures and anisotropy on the ultrasound stress waves in FGA smart materials. The numerical findings verify the proposed methodology’s validity and accuracy. We may conclude that the offered results are useful for comprehending the FGA smart materials. As a result, our findings contribute to the advancement of the industrial applications of FGA smart materials.
Źródło:
Computer Methods in Materials Science; 2021, 21, 2; 95-104
2720-4081
2720-3948
Pojawia się w:
Computer Methods in Materials Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Uncertainty and accuracy of vision-based tracking concerning stereophotogrammetry and noise-floor tests
Autorzy:
Ngeljaratan, Luna
Moustafa, Mohamed A.
Powiązania:
https://bibliotekanauki.pl/articles/2051854.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
stereophotogrammetry
noise-floor
vision-based tracking
displacement
uncertainty
accuracy
Opis:
This work proposes a systematic assessment of stereophotogrammetry and noise-floor tests to characterize and quantify the uncertainty and accuracy of a vision-based tracking system. Two stereophotogrammetry sets with different configurations, i.e., some images are designed and their sensitivity is quantified based on several assessments. The first assessment evaluates the image coordinates, stereo angle and reconstruction errors resulting from the stereophotogrammetry procedure, and the second assessment expresses the uncertainty from the variance and bias errors measured from the noise-floor test. These two assessments quantify the uncertainty, while the accuracy of the vision-based tracking system is assessed from three quasi-static tests on a small-scaled specimen. The difference in each stereophotogrammetry set and configuration, as indicated by the stereophotogrammetry and noise-floor assessment, leads to a significant result hat the first stereophotogrammetry set measures the RMSE of 3.6 mm while the second set identifies only 1.6 mm of RMSE. The results of this work recommend a careful and systematic assessment of stereophotogrammetry and noise-floor test results to quantify the uncertainty before the real test to achieve a high displacement accuracy of the vision-based tracking system.
Źródło:
Metrology and Measurement Systems; 2022, 29, 1; 75-92
0860-8229
Pojawia się w:
Metrology and Measurement Systems
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Identification of water treatment plant based on feedforward neural network
Autorzy:
Mohamed, A. F.
Radwa, H. Z.
Powiązania:
https://bibliotekanauki.pl/articles/971051.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:
water treatment plant
coagulation process
PID
neural network control
Opis:
Coagulation process is the main process in conventional water treatment process sequence. It influences the following treatment process aspects: maintaining plant efficiency and increasing the quality of the produced water. This is accomplished by adding chemicals to raw water, such as alum sulphate. To secure the appropriate plant performance, a mathematical model is proposed in this paper for the coagulation unit, followed by the development of the control strategy. Classic PID and neural network based controller regulating the process are used. Tests were performed, based on the real data for water treatment, using MATLAB/SIMULINK. Simulation results showed better values for both settling time and overshoot in the case of using neural network based controller than PID.
Źródło:
Control and Cybernetics; 2017, 46, 3; 247-258
0324-8569
Pojawia się w:
Control and Cybernetics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Unconventional alternatives for control of tomato root rot caused by Rhizoctonia solani under greenhouse conditions
Autorzy:
Hamza, A.
Mohamed, A.
Derbalah, A.
Powiązania:
https://bibliotekanauki.pl/articles/66331.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
biological agent
control
tomato
root rot
Rhizoctonia solani
greenhouse condition
plant oil
nanoparticle
Opis:
This study was done to assess the antifungal effect of some biocontrol agents effective microorganisms (EMs1), Pseudomonas fluorescences, and Bacillus pumilus, titanium dioxide (TiO2) nanoparticles, black cumin and wheat germ oils as well as the recommended fungicide (flutolanil) against root rot of tomato. Moreover, gas chromatography-mass spectrometry (GC-MS) examination was completed to identify the bioactive compounds in plant oils (dark cumin and wheat germ). Also the impact of these medicines on some biochemical and growth parameters of tomato was examined. Flutolanil was the best treatment followed by dark cumin, TiO2, EMs1, Pseudomonas fluorescens, Bacillus pumilus and wheat germ oil, individually in both test seasons. The outcomes demonstrated a marked increase in each biochemical character (chlorophyll substance, peroxidase and polyphenoloxidase) and plant development (height and fresh and dry weight) under all the tried treatments in comparison to the controls.
Źródło:
Journal of Plant Protection Research; 2016, 56, 3
1427-4345
Pojawia się w:
Journal of Plant Protection Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental and Computational Vibration Study of Amino Acids
Autorzy:
Mohammed, M. E.
Mohamed, A. M. A.
Powiązania:
https://bibliotekanauki.pl/articles/412478.pdf
Data publikacji:
2013
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Vibrational studies
Amino Acids
semi-empirical methods (PM6 and RM1)
ab initio methods (B3LYP/6-31+G(d)
Opis:
Vibrational studies of amino acids experimentally and theoretically have been performed. The Semi-empirical methods optimization by PM6 and RM1 on the l- and d-amino acids (alanine, phenylalanine, aspartic and glutamic acid), showed no difference in energy between l-and d-isomers. The vibrational frequencies were calculated by semi-emprical methods (PM6 and RM1) and ab initio methods (B3LYP/6-31+G(d) and were scaled down by factors of 0.925 (RM1), 1.09 (PM6) and 0.89 (B3LYP/6-31+G(d)). The calculated and experimental vibrational frequencies have shown good general agreement.
Źródło:
International Letters of Chemistry, Physics and Astronomy; 2013, 10, 1; 1-17
2299-3843
Pojawia się w:
International Letters of Chemistry, Physics and Astronomy
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Exploitation of spent nickel-metal hydride (Ni-MH) batteries as a source of value-added products
Autorzy:
Farghal, Fatma E.
Abdel-Khalek, Mohamed A.
Powiązania:
https://bibliotekanauki.pl/articles/2146864.pdf
Data publikacji:
2021
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
nickel–metal hydride
batteries
nickel
recovery
cementation
leaching
recycling
Opis:
Spent Nickel–metal hydride batteries can be sources of valuable metals such as nickel, cobalt, manganese, rare earths and toxic chemicals. The recycling of these materials is necessary from both economic and environmental points of view. In this study the nickel is leached in acid solution followed by precipitation and thermal decomposition or by cementation. The affecting parameters such as acid type and concentration, time, temperature and solid/liquid ratio were investigated. The maximum of leached nickel could be obtained in 3M sulfuric acid at 65°C for 60 min with solid-to-liquid ratio of 30 g L-1. The liquid film is a more suitable model for demonstrating the kinetics of the nickel leaching. Thermal decomposition of the precipitated nickel dimethyl-glyoxime was employed in preparation of nickel oxide. Nickel was separated from aqueous solution by cementation on zinc. The cementation process follows pseudo first-order kinetics and diffusion controlling steps. The yield was 91% of the original nickel content.
Źródło:
Physicochemical Problems of Mineral Processing; 2021, 57, 6; 95--101
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Low Back Muscle Activity in an Automobile Seat with a Lumbar Massage System
Autorzy:
Kolich, M.
Taboun, S. M.
Mohamed, A. I.
Powiązania:
https://bibliotekanauki.pl/articles/90384.pdf
Data publikacji:
2000
Wydawca:
Centralny Instytut Ochrony Pracy
Tematy:
automotive seating
electromyography
low back pain
ból pleców
elektromiografia
masaż
Opis:
This investigation was conducted to determine the effects of a massaging lumbar support system on low back muscle activity. The apparatus included a luxury-level automobile seat, six 10-mm diameter bipolar surface electrodes, an amplifier, an anaiog-to-digital conversion board, data acquisition software, and a personal computer. Six experimental conditions, each involving a variation of massage time, were considered. The dependent variable was the change in the root mean square variation of the EMG signal. One minute of lumbar massage every 5 min was found to have a beneficial effect on low back muscle activity (as compared to no massage). This may prove to be an extremely important result in the quest to combat low back pain attributable to automobile seating.
Źródło:
International Journal of Occupational Safety and Ergonomics; 2000, 6, 1; 113-128
1080-3548
Pojawia się w:
International Journal of Occupational Safety and Ergonomics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of foliar application of Sida compound fertilizer on growth, yield, and fruit chemical composition of "Early Superior" grapevine
Autorzy:
Mohamed, A.-R.M.A.
Abdel-Aziz, F.H.
Mohamed, M.A.
Gobara, A.
Powiązania:
https://bibliotekanauki.pl/articles/2087.pdf
Data publikacji:
2013
Wydawca:
Instytut Ogrodnictwa
Tematy:
foliar application
natural fertilizer
growth
vegetative growth
yield
fruit
chemical composition
grape-vine
Early Superior cultivar
leaf mineral content
Źródło:
Journal of Horticultural Research; 2013, 21, 2
2300-5009
Pojawia się w:
Journal of Horticultural Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The impact of smart transformer on different radialdistribution systems
Autorzy:
Mahmoud, Ibrahem Mohamed A.
Abdelsalam, Tarek Saad
Swief, Rania
Powiązania:
https://bibliotekanauki.pl/articles/1841278.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
smart transformer
smart grid
direct approach
power flow
power loss reduction
inteligentny transformator
inteligentna sieć
bezpośrednie podejście
przepływ mocy
redukcja strat mocy
Opis:
The work is intended to extend the application of a smart transformer on a radialdistribution system. In this paper, an updated algorithm on the backward/forward powerflow is introduced. The so-called direct approach of power flow is employed and analyzed.In addition, the paper focused on integrating a smart transformer to the network and solvingthe updating network also using the direct approach load flow. The solution of the smarttransformer using the direct approach power flow method is quite straightforward. Thismodel is applied to radial distribution systems which are the IEEE 33- and IEEE 69-bussystems as a case study. Also, the paper optimizes the best allocation of the smart transformerto reduce the power losses of the grid.
Źródło:
Archives of Electrical Engineering; 2021, 70, 2; 271-283
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
CuO–water mhd mixed convection analysis and entropy generation minimization in double-lid–driven u-shaped enclosure with discrete heating
Autorzy:
Mliki, Bouchmel
Miri, Rached
Djebali, Ridha
Abbassi, Mohamed A.
Powiązania:
https://bibliotekanauki.pl/articles/2204647.pdf
Data publikacji:
2023
Wydawca:
Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
Tematy:
U-shaped enclosure
MHD mixed convection
nanoliquids
double lid-driven cavity
entropy generation
LBM
Opis:
The present study explores magnetic nanoliquid mixed convection in a double lid–driven U-shaped enclosure with discrete heat-ing using the lattice Boltzmann method (LBM) numerical method. The nanoliquid thermal conductivity and viscosity are calculated using the Maxwell and Brinkman models respectively. Nanoliquid magnetohydrodynamics (MHD) and mixed convection are analyzed and entropy generation minimisation has been studied. The presented results for isotherms, stream isolines and entropy generation describe the interaction between the various physical phenomena inherent to the problem including the buoyancy, magnetic and shear forces. The operating parameters’ ranges are: Reynolds number (Re: 1–100), Hartman number (Ha: 0–80), magnetic field inclination (γ: 0°–90°), nanoparticles volume fraction (ϕ: 0–0.04) and inclination angle (α: 0°–90°). It was found that the and the total entropy generation augment by increasing Re, ϕ: and γ. conversely, an opposite effect was obtained by increasing Ha and α. The optimum magnetic field and cavity inclination angles to maximum heat transfer are γ = 90° and α = 0.
Źródło:
Acta Mechanica et Automatica; 2023, 17, 1; 112--123
1898-4088
2300-5319
Pojawia się w:
Acta Mechanica et Automatica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Second law analysis of mhd forced convective nanoliquid flow through a two-dimensional channel
Autorzy:
Miri, Rached
Abbassi, Mohamed A.
Ferhi, Mokhtar
Djebali, Ridha
Powiązania:
https://bibliotekanauki.pl/articles/2204682.pdf
Data publikacji:
2022
Wydawca:
Politechnika Białostocka. Oficyna Wydawnicza Politechniki Białostockiej
Tematy:
MHD
LBM
channel flow
nanoliquids
entropy generation
Brownian motion
Opis:
The present study deals with fluid flow, heat transfer and entropy generation in a two-dimensional channel filled with Cu–water nanoliquid and containing a hot block. The nanoliquid flow is driven along the channel by a constant velocity and a cold temperature at the inlet, and the partially heated horizontal walls. The aim of this work is to study the influence of the most important parameters such as nanoparticle volume fraction (0%≤ϕ≤4%), nanoparticle diameter (5 nm≤dp≤55 nm), Reynolds number (50≤Re≤200), Hartmann number (0≤Ha≤90), magnetic field inclination angle (0≤γ≤π) and Brownian motion on the hydrodynamic and thermal characteristics and entropy generation. We used the lattice Boltzmann method (LBM: SRT-BGK model) to solve the continuity, momentum and energy equations. The obtained results show that the maximum value of the average Nusselt number is found for case (3) when the hot block is placed between the two hot walls. The minimum value is calculated for case (2) when the hot block is placed between the two insulated walls. The increase in Reynolds and Hartmann numbers enhances the heat transfer and the total entropy generation. In addition, the nanoparticle diameter increase reduces the heat transfer and the irreversibility, the impact of the magnetic field inclination angle on the heat transfer and the total entropy generation is investigated, and the Brownian motion enhances the heat transfer and the total entropy generation.
Źródło:
Acta Mechanica et Automatica; 2022, 16, 4; 417--431
1898-4088
2300-5319
Pojawia się w:
Acta Mechanica et Automatica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Dynamics of Trade Openness in Sri Lanka
Autorzy:
Mohamed Aslam, A. L.
Powiązania:
https://bibliotekanauki.pl/articles/1178315.pdf
Data publikacji:
2017
Wydawca:
Przedsiębiorstwo Wydawnictw Naukowych Darwin / Scientific Publishing House DARWIN
Tematy:
Gross Domestic Product
Money supply
Sri Lanka
Trade openness
Opis:
In Sri Lanka, even it was verbally confirmed that the trade openness occurs the wonder on the economy of Sri Lanka, which was not statistically proofed. This study was to test the trade openness dynamics of the economic growth in Sri Lanka using annual time series data over the period of 1975 to 2014. In this study the following variables were used as variables gross domestic product, which was the proxy variable of the economic growth, the trade openness and the money supply. Furthermore, in order to test the long run relationship between the variables, the Johansen cointegration technique was employed while, the VECM technique was employed to test the short run behaviour of the trade openness. In this study, both techniques confirmed that the trade openness negatively and significantly had the long run relationship with the economic growth. While, the lag values of the trade openness in short run period, jointly had not impacted on the economic growth over the sample period. Finally, this study recommended to the government of Sri Lanka that the export should be increased when they formulate the trade development policy.
Źródło:
World Scientific News; 2017, 81, 2; 94-105
2392-2192
Pojawia się w:
World Scientific News
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The history of genome mapping in Fragaria spp.
Autorzy:
Mohamed, A.-R. M. A.-W.
Jecz, T.
Korbin, M.
Powiązania:
https://bibliotekanauki.pl/articles/2139.pdf
Data publikacji:
2014
Wydawca:
Instytut Ogrodnictwa
Tematy:
woodland
strawberry
genome mapping
Fragaria vesca
mapping population
linkage
physical mapping
disease resistance
fruit colour
photoperiodic flower
Źródło:
Journal of Horticultural Research; 2014, 22, 2
2300-5009
Pojawia się w:
Journal of Horticultural Research
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Potential Application of Used Coffee Grounds in Leather Tanning
Autorzy:
Nasr, Ahmed I.
El Shaer, Mohammed A.
Abd-Elraheem, Mohamed A.
Powiązania:
https://bibliotekanauki.pl/articles/24201785.pdf
Data publikacji:
2023
Wydawca:
Polskie Towarzystwo Inżynierii Ekologicznej
Tematy:
leather properties
tannins
vegetable tanning
Opis:
Safety of environment and human health is an essential requirement of modern industrial techniques. Therefore, using natural agents in tanning industry may emerge as a trusted method to avoid the chemical contamination caused by using traditional chromium salts in tanning process. This study aimed to evaluate the hot water extract of used coffee grounds (UCGs) as a vegetable tanning agent. The collected UCGs were dried and extracted with hot water at 90 °C for 2h. The phytochemical screening properties of UCGs extract were determined. Sufficient amount of extract was prepared to be used in leather tanning. Three groups were tanned with UCGs extract solely at concentrations of 20, 30 or 40% of pelts’ weight, while another three groups were tanned with the same concentrations and then re-tanned with 10% of a synthetic tanning agent “Phenol sulfonates”. On tanned leathers, organoleptic, physical and chemical properties were determined; scanning electron micrographs were depicted to examine the leather surface and collagen fiber bundles. Analysis of UCGs extract revealed that it has good tanning properties, as it contained tannins (14.92%), tannins/non tannins ratio (2.06), hide powder (39.57) and Stiasny number (21.16). The results of leather properties showed that using UCGs extract alone at concentration of 40% achieved the best results for the vegetable tanning where the tanned leather had higher (P<0.05) tensile strength, tearing strength and shrinking temperature than that treated with the lower level of 20% UCGs extract. However, 40% of UCGs extract is highly recommended to be used to accomplish the required shrinkage temperature that should be ≥ 70 °C. UCGs extract could be successfully used as tanning agent in vegetable tanning to produce durable leathers with good fullness; it may be used for different manufacturing products, such as footwear and bags. Moreover, using a combination of UCGs extract at any of the used concentrations with phenol sulfonates 10% led to significant improvement in all studied traits as compared with using UCGs extract alone.
Źródło:
Journal of Ecological Engineering; 2023, 24, 3; 10--19
2299-8993
Pojawia się w:
Journal of Ecological Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Impact of cationic-anionic surfactants on selective oil agglomeration of oil shale
Autorzy:
Abdel-Khalek, Mohamed A.
Amin, Rasha
Hassan, El-Sayed R. E.
Powiązania:
https://bibliotekanauki.pl/articles/1450561.pdf
Data publikacji:
2020
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
oil shale
oil agglomeration
kerogen
surfactants
zeta potential
Opis:
Egyptian oil shale from Red Sea area is upgraded via oil agglomeration technique to achieve a clean fuel. A representative sample is characterized to identify its undesirable components and its liberation size. The quartz, apatite, calcite, siderite and anhydrite are the main gangue minerals. The sample was pulverized to less than 20 µm for efficient liberation. The impact of anionic (Calcium dodecyl benzene sulfonate, CDBS) or/and cationic (Cetrimonium bromide, CTAB) surfactants on the zeta-potential and agglomeration process was investigated in presence of different kerosene concentrations. A concentrate of 62% kerogen with 95% recovery was obtained from feed of 29% kerogen using 0.1% CTAB/CDBS mixture in 2% kerosene emulsion.
Źródło:
Physicochemical Problems of Mineral Processing; 2020, 56, 6; 137-144
1643-1049
2084-4735
Pojawia się w:
Physicochemical Problems of Mineral Processing
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
First report on Noctiluca scintillans blooms in the Red Sea off the coasts of Saudi Arabia: consequences of eutrophication
Autorzy:
Mohamed, Z.A.
Mesaad, I.
Powiązania:
https://bibliotekanauki.pl/articles/48017.pdf
Data publikacji:
2007
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
microalga
dinoflagellate
bloom
coast
eutrophication
Saudi Arabia
Red Sea
Noctiluca scintillans
Opis:
Blooms of Noctiluca scintillans are reported for the first time in the Red Sea off the south-western coasts of Saudi Arabia. During the present study, surface water samples were collected weekly on the coasts of the Al Shuqayq region from February to April 2004–2006. The abundance of N. scintillans correlated negatively with most nutrients, as well as the cell densities of diatoms and dinoflagellate species. Microscopic examination of live cells from Noctiluca blooms showed the presence of some species of diatoms and dinoflagellates within the Noctiluca body – confirmation of its grazing on these microalgae. The presence of a Noctiluca bloom in the coastal waters off south-western Saudi Arabia could be linked indirectly to water eutrophication by an increase in prey abundance. The physico-chemical properties of Red Sea coastal waters should therefore be monitored regularly in order to minimize the formation of harmful algal blooms, which may affect all food web levels, including the human level.
Źródło:
Oceanologia; 2007, 49, 3
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Molecular diversity of two-spotted spider mite (Tetranychus urticae) in apple orchards across Poland and its potential link with the resistance to METI-acaricides
Autorzy:
Jecz, T.
Korbin, M.
Gorzka, D.
Mohamed, A.-R.A.
Olszak, R.
Powiązania:
https://bibliotekanauki.pl/articles/1853.pdf
Data publikacji:
2018
Wydawca:
Instytut Ogrodnictwa
Tematy:
molecular diversity
two-spotted spider mite
Tetranychus urticae
apple orchard
Polska
acaricide resistance
pesticide
random amplified polymorphic DNA
acaricide
bioassay
Źródło:
Journal of Horticultural Research; 2018, 26, 2
2300-5009
Pojawia się w:
Journal of Horticultural Research
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:
Field and modelling study for deficit irrigation strategy on roots volume and water productivity of wheat
Autorzy:
Abdelraouf, Ramadan E.
El-Shawadfy, Mohamed A.
Dewedar, Osama M.
Hozayn, Mahmoud
Powiązania:
https://bibliotekanauki.pl/articles/1844310.pdf
Data publikacji:
2021
Wydawca:
Instytut Technologiczno-Przyrodniczy
Tematy:
irrigation
roots volume
SALTMED model
soil moisture
water productivity
wheat
Opis:
In many regions of the world, including Egypt, water shortages threaten food production. An irrigation deficient strategy in dry areas has been widely investigated as a valuable and sustainable approach to production. In this study, the dry matter and grain yield of wheat was decreased by reducing the amount of irrigation water as well as the volume of the root system. As a result of this, there was an increase the soil moisture stress. This negatively affected the absorption of water and nutrients in the root zone of wheat plants, which ultimately had an effect on the dry matter and grain yield of wheat. The values of dry matter and grain yield of wheat increased with the ʻSakha 94ʼ variety compared to the ʻSakha 93ʼ class. It is possible that this was due to the increase in the genetic characteristic of the root size with the ʻSakha 94ʼ variety compared to the ʻSakha 93ʼ class, as this increase led to the absorption of water and nutrients from a larger volume of root spread. Despite being able to increase the water productivity of wheat by decreasing the amount of added irrigation water, the two highest grain yield values were achieved when adding 100% and 80% of irrigation requirements (IR) needed to irrigate the wheat and no significant differences between the yield values at 100% and 80% of IR were found. Therefore, in accordance with this study, the recommended irrigation for wheat is at 80% IR which will provide 20% IR. When comparing the water productivity of two wheat varieties in study, it becomes clear that ʻSakha 94ʼ was superior to ʻSakha 93ʼ when adding the same amount of irrigation water, and this resulted in increased wheat productivity for ʻSakha 94ʼ. The SALTMED results confirmed good accuracy (R2: 0.92 to 0.98) in simulating soil moisture, roots volume, water application efficiency, dry matter, and grain yield for two varieties of wheat under deficit irrigation conditions. Whilst using sprinkler irrigation system under sandy soils in Egypt.
Źródło:
Journal of Water and Land Development; 2021, 49; 129-138
1429-7426
2083-4535
Pojawia się w:
Journal of Water and Land Development
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Minimizing of tunneling effect on existing infrastructure in Egypt
Autorzy:
Asker, Kamel I.
Fouad, Mohamed T.
Bahr, Mohamed A.
El-Attar, Ahmed N.
Powiązania:
https://bibliotekanauki.pl/articles/35525187.pdf
Data publikacji:
2021
Wydawca:
Szkoła Główna Gospodarstwa Wiejskiego w Warszawie. Wydawnictwo Szkoły Głównej Gospodarstwa Wiejskiego w Warszawie
Tematy:
tunneling
grouting
field measurements
Abaqus
Al-Azhar twin tunnel
Opis:
A set of parametric studies by using the Abaqus software is conducting to investigate the effective method to seal the CWO sewer from the tunneling process. These methods include: (i) two deep grouted walls, (ii) adjacent slurry piles, (iii) bored reinforced concrete piles assisted with slurry piles, and (iv) grouted block confining the twin tunnel wall. Based on the results of parametric studies. Most of the protective studied technique was effective on reducing the tunneling effect on the ground movements.
Źródło:
Scientific Review Engineering and Environmental Sciences; 2021, 30, 1; 3-15
1732-9353
Pojawia się w:
Scientific Review Engineering and Environmental Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
English phonological errors by Kimakunduchi speaking EFL learners in Zanzibar
Autorzy:
Mohamed, Salim A.
Msuya, Erasmus A.
Powiązania:
https://bibliotekanauki.pl/articles/2082782.pdf
Data publikacji:
2020-12-13
Wydawca:
Uniwersytet Warszawski. Wydział Orientalistyczny. Katedra Języków i Kultur Afryki
Tematy:
consonants
foreign language
interlanguage
Kimakunduchi
language errors
Opis:
The aim of the present study was to find the phonological errors on segmental level involving selected consonant sounds which are produced by Kimakunduchi speaking English as Foreign Language (EFL) learners in Zanzibar. Specifically, the study sought to provide the evidence of cross-linguistic influence involving phonological transfer on segmental level. The study employed two sampling techniques: stratified and random sampling. The data for this study were collected from three secondary schools located at Makunduchi district in Unguja Island – Makunduchi, Kusini, and Kizimkazi secondary schools – using the oral interview and observation. The data were analyzed with the use of both qualitative and quantitative research approach. The study was guided by the transfer theory which was one of the components of Selinker’s (1992: 209) interlanguage theory. The findings revealed that, to a large extent, native Kimakunduchi speakers of EFL tended to transfer the sounds existing in their L1, or even in Kiswahili, into English. The transfer was done because of the nonexistence of the particular sound in the students’ native language or because of the discrepancy of spelling and pronunciation in English language. The study concludes that an articulation of vowels is more complex compared to consonants because of their absence in the first language (L1) or because of the confusion of spelling and pronunciation in English as FL. Thus, the study recommended that serious measures should be taken from both education holders to make sure that the learners could be able to pronounce English phonemes/words correctly.
Źródło:
Studies in African Languages and Cultures; 2020, 54; 121-141
2545-2134
2657-4187
Pojawia się w:
Studies in African Languages and Cultures
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Description of Triangulamyxa psittaca sp. n. (Myxozoa: Myxosporea), a new parasite in the urinary bladder of Colomesus psittacus (Teleostei) from the Amazon River, with emphasis on the ultrastructure of plasmodial stages
Autorzy:
Rocha, Sónia
Casal, Graça
Matos, Patrícia
Matos, Edilson
Dkhil, Mohamed A.
AZEVEDO, Carlos
Powiązania:
https://bibliotekanauki.pl/articles/763644.pdf
Data publikacji:
2011
Wydawca:
Uniwersytet Jagielloński. Wydawnictwo Uniwersytetu Jagiellońskiego
Tematy:
Ultrastructure, plasmodia, myxosporean, Triangulamyxa psittaca sp. nov., parasite, urinary bladder, freshwater fish, Colomesus psittacus
Opis:
A fish-infecting myxosporean was found in the urinary bladder of the teleostean Colomesus psittacus, collected from the Amazon River, Brazil. Specimens were sampled in three different periods: May and June, with water temperature ranging from 18–23ºC; August, with water temperature ranging from 24–28ºC; and November and December, with water temperature ranging from 29–32ºC. Upon observation, several fish displayed abnormal behaviour, consisting of erratic movements, and mortality was recorded among them. Necropsy of all sampled fishes revealed hypertrophy of the urinary bladder only among specimens previously displaying the irregular behaviour. Microscopic analysis of this organ confirmed the parasitic infection, resulting in the observation of spores floating free in the urine, and numerous plasmodia attached to the epithelium of the urinary bladder. Light and ultrastructural studies allowed recognition of the spores and plasmodia morphological characteristics. Coelozoic plasmodia were polysporic with varying organizational structure, according to the sampling period. Spores were equilaterally triangular with rounded ends in valvar view, measuring 8.8 ± 0.4 μm (n = 30) in length and 8.4 ± 0.5 μm (n = 30) in width, and displaying a ridge surface pattern. Two polar capsules were observed in the anterior end of the spores, measuring 3.1–3.2 μm in diameter. The spores were morphologically identified as belonging to the recently described genus Triangulamyxa. Further observation and comparison to the morphological features described for Triangulamyxa amazonica, the only other species within this genus, allowed us to conclude our parasite as a new species, herein named Triangulamyxa psittaca sp. nov. from the Amazon River, Brazil. Also, three different stages were distinguished in the plasmodium evolution, based on the observed morphological features at the three sampling periods. Fish sampled during May and June displayed small plasmodia (up to ~ 15–20 μm long), containing early stages of sporogenic development. Fish sampled during November and December presented larger plasmodia (up to ~ 850 μm long), which appeared flattened against and lining the urinary bladder epithelial cells and contained the later stages of sporogenic development, including some mature spores. Fish sampled during August presented plasmodia displaying intermediate morphological features between those observed in infected fish from the other sampling periods. Several immature and mature spores were among the different developmental stages. The parasite-host interface evolution is described throughout the different observed stages, with emphasis on the formation of septate junctions. Considering several previous reports, as well as the different environmental conditions during the sampling periods, the plasmodium development here described appears to be influenced by environmental factors, namely water temperature.
Źródło:
Acta Protozoologica; 2011, 50, 4
1689-0027
Pojawia się w:
Acta Protozoologica
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Efficient H.264 Intra Frame CODEC with Best Prediction Matrix Mode Algorithm
Autorzy:
Hamdy, Sara
Zekry, Abdelhalim
Mohamed, Wael A.
Powiązania:
https://bibliotekanauki.pl/articles/226164.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
best prediction matrix mode (BPMM)
compression efficiency
H.264/AVC
Huffman coding
Intra prediction
Opis:
The continuous growth of smart communities and ever-increasing demand of sending or storing videos, have led to consumption of huge amount of data. The video compression techniques are solving this emerging challenge. However, H.264 standard can be considered most notable, and it has proven to meet problematic requirements. The authors present (BPMM) as a novel efficient Intra prediction scheme. We can say that the creation of our proposed technique was in a phased manner; it's emerged as a proposal and achieved impressive results in the performance parameters as compression ratios, bit rates, and PSNR. Then in the second stage, we solved the challenges of overcoming the obstacle of encoding bits overhead. In this research, we try to address the final phase of the (BPMM) codec and to introduce our approach in a global manner through realization of decoding mechanism. For evaluation of our scheme, we utilized VHDL as a platform. Final results have proven our success to pass bottleneck of this phase, since the decoded videos have the same PSNR that our encoder tells us, while preserving steady compression ratio treating the overhead. We aspire our BPMM algorithm will be adopted as reference design of H.264 in the ITU.
Źródło:
International Journal of Electronics and Telecommunications; 2020, 66, 3; 571-582
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Occurrence and germination of dinoflagellate cysts in surface sediments from the Red Sea off the coasts of Saudi Arabia
Autorzy:
Mohamed, Z.A.
Al-Shehri, A.M.
Powiązania:
https://bibliotekanauki.pl/articles/48723.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Instytut Oceanologii PAN
Tematy:
occurrence
germination
dinoflagellate cyst
cyst
Red Sea
Saudi Arabia
coast
toxic species
distribution
abundance
surface sediment
organic carbon
silt
clay
Cochlodinium polykrikos
Prorocentrum minimum
Dinophysis
acuminata
Alexandrium catenell
Scrippsiella trochoidea
Opis:
The distribution and abundance of dinoflagellate cyst assemblages were investigated in surface sediments from south-western Red sea coasts of Saudi Arabia at six sites during March 2010. A total of 19 taxa of dinoflagellate cysts were identified from all sites. The sampling sites showed a similar cyst assemblage, but they differed in total cyst abundance (3 to 4083 cysts g−1 dry weight). Cyst abundance was strongly correlated with sediment characteristics, the highest numbers being recorded in sediments with large contents of organic carbon, silt and clay. Cyst assemblages were dominated by cysts of potentially toxic species, including Cochlodinium polykrikos, Prorocentrum minimum, Dinophysis acuminata, Alexandrium catenella and Scrippsiella trochoidea. Most cysts germinated successfully at different rates at 15 and 25◦C. This study suggests that surface sediments from all Saudi Red Sea coasts should be monitored for the presence of dinoflagellate cysts to give ample warning of the presence and abundance of toxic species in a given area.
Źródło:
Oceanologia; 2011, 53, 1
0078-3234
Pojawia się w:
Oceanologia
Dostawca treści:
Biblioteka Nauki
Artykuł

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