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Groundwater Management at West El-Minia Desert Area, Egypt Using Numerical Modeling

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Journal of Geoscience and Environment Protection 2016年第7期4卷 66-76页

作者： Ahmed A. abdel Moneim José Paulino Fernández-Álvarez Elsayed M. Abu El Ella Ahmed M. Masoud Geology Department Faculty of Science Sohag University Sohag Egypt hydro-Geophysics and NDT Modeling Unit Polytechnic School of Mieres University of Oviedo Mieres Spain Geology Department Faculty of Science Assiut University Assiut Egypt

Water shortage is the main problem facing any development in Egypt especially in the desert lands. River Nile is considered the main source of water in Egypt but its water covers only the area of flood plain where its tributaries do not reach to the desert. The desert fringes, west of El-Minia governorate, Egypt, are areas of natural expansion for agricultural, industrial, and civil activities. This implies an increasing demand for groundwater. A numerical groundwater model is one of the main tools used for assessment of the resource potential and prediction of future impact under different circumstances and stresses. in this paper, a transient groundwater flow model in the desert district west of El-Minia, Egypt, was developed. The conceptual model was built by analyzing the hydrogeological data and previous work. Steady state model of year 1990 was used to investigate and calibrate the parameters such as hydraulic conductivities, recharge and conductance of the surface water streams. The storage coefficients are calibrated by the transient model based on the available data observed from 1990 to 2013, which provides insights to understand the behavior of groundwater system in Quaternary Aquifer and to predict spatial-temporal distributions of groundwater levels and groundwater flow in responding to extraction of water. The calibrated transient model will be used to predict the impacts of desert development schemes and water resources management schemes on groundwater in the study area.

关键词： Groundwater Flow Model El-Minia Groundwater Management Quaternary Aquifer

Radiological hazards for Marble and Granite Used at Shak El Thouban industrial Zone in Egypt

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Journal of Environmental Protection 2013年第12期4卷 41-48页

作者： Amany T. Sroor Saher M. Darwish Samia M. El-Bahi Mohamed G. abdel Karim Nuclear Physics Laboratory Faculty of Girls Ain Shams University Cairo Egypt Physics Department Faculty of Science Cairo University Giza Egypt

The background level of radiation in the natural environment surrounds us at all times. Levels of natural occurring radioactivity in marble and granite used at Shak El Thouban industrial zone in Cairo, Egypt have been investigated using hPGe detector through gamma-ray spectrometry. The activity concentration of radionuclides in the 238U-, 232Th-series and 40K has been determined. The average activity concentration of 238U, 232Th and 40K for marble samples was 23.77 Bq/kg ranged from (10.91 to 45.4), 10.75 Bq/kg ranged from (5.46 to 23.61) and 520.43 Bq/kg ranged from (382.30 to 1132.41), respectively. The 238U, 232Th and 40K activity concentration for granite samples were 54.31 Bq/kg ranged from (12.04 to 106.34), 113.57 Bq/kg ranged from (23.91 to 270.36) and 7867.51 Bq/kg ranged from (2017.60 to 11436.91), respectively. Concerning the radiological risk, the radium equivalent activity, external and internal radiation hazard indices, the radiation level index and absorbed dose rate were evaluated. The mass exhalation rates of 222Rn and emanation coefficient have been also calculated. The mass exhalation rate of radon was found to be from 14.86 to 137.13 and 16.48 to 155.26 μBq/kg·s for marble and granite samples, respectively. The mean values of the specific activity of 226Ra, activity of 238U before and after sealing time and the mass exhalation rate of radon for granite samples are twice that for marble samples. All radiological indices and the mass exhalation rate of radon are lower than the permissible levels for building material in all marble samples, while all granite samples are higher and unsafe and pose a risk to the workers and users of these products due to the emanation of radon that may accumulate by time, especially in closed spaces.

关键词： Radiological hazards Marble Granite hPGe Detector Shak El Thouban

A numerical study on the influence of grain boundary oxides on dwell fatigue crack growth of a nickel-based superalloy

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Journal of Materials Science & Technology 2022年第9期104卷 224-235页

作者： C.Z.Fang h.C.Basoalto M.J.Anderson h.Y.Li S.J.Williams P.Bowen Department of Materials Science and Engineering University of SheffieldMappin StSheffield S13JDUK School of Metallurgy and Materials University of BirminghamEdgbastonBirmingham B152TTUK institute of Structural Materials Swansea UniversitySwansea SA18ENUK

A theoretical treatment on the oxide-controlled dwell fatigue crack growth of aγ'strengthened nickelbased superalloys is *** particular,this study investigates the influence of an externally applied load and variations in theγ'dispersion on the grain boundary oxide growth kinetics.A dislocation-based viscoplastic constitutive description for high temperature deformation is used to simulate the stress state evolution in the vicinity of a crack at elevated *** viscoplastic model explicitly accounts for multimodalγ'particle size distributions.A multicomponent mass transport formulation is used to simulate the formation/evolution of an oxide wedge ahead of the crack tip,where stress-assisted vacancy diffusion is assumed to *** resulting set of constitutive and mass transport equations have been implemented within a finite element *** of predicted compositional fields across the matrix/oxide interface are compared with experiments and shown to be in good *** indicate that the presence of a fineγ'size distribution has a strong influence on the predicted ow stress of the material and consequently on the relaxation in the vicinity of the crack-tip/oxide *** is shown that a unimodal dispersion leads to reduced oxide growth rates(parabolic behavior)when compared to a bimodal *** conditions for oxide formation are investigated and is associated with the prediction of compressive stresses within the oxide layer just ahead of the crack tip,which become progressively negative as the oxide wedge ***,mechanical equilibrium requirements induce tensile stresses at the tip of the oxide wedge,where failure of the oxide is *** time taken to reach this critical stress for oxide failure has been calculated,from which dwell crack growth rates are computationally *** predicted rates are shown to be in good agreement with available experimental data.

关键词： Nickel based superalloy Dwell crack growth Gamma prime Creep Oxidation Dislocation-based modeling Multicomponent diffusion Finite element method

Experimentally validated atomistic simulation of the effect of relevant grinding parameters on work piece topography,internal stresses,and microstructure

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Friction 2022年第4期10卷 608-629页

作者： S.J.EDER P.G.GRÜTZMAChER T.SPENGER h.hECKES h.ROJACZ A.NEVOSAD F.hAAS AC2T research Gmbh Viktor-Kaplan-Straße 2/CWiener Neustadt 2700Austria institute of Engineering Design and Product Development TU WienLehárgasse 6-Objekt 7Vienna 1060Austria institute of Production Engineering Graz University of TechnologyKopernikusgasse 24/IGraz 8010Austria Tyrolit-Schleifmittelwerke Swarovski K.G. Swarovskistraße 33Schwaz 6130Austria

in this work,we present a fully atomistic approach to modeling a finishing process with the goal to shed light on aspects of work piece development on the microscopic scale,which are difficult or even impossible to observe in experiments,but highly relevant for the resulting material *** a large-scale simulative parametric study,we varied four of the most relevant grinding parameters:The work piece material,the abrasive shape,the temperature,and the infeed *** order to validate our model,we compared the normalized surface roughness,the power spectral densities,the steady-state contact stresses,and the microstructure with proportionally scaled macroscopic experimental *** the grain sizes vary by a factor of more than 1,000 between experiment and simulation,the characteristic process parameters were reasonably reproduced,to some extent even allowing predictions of surface quality degradation due to tool *** the experimentally validated model,we studied time-resolved stress profiles within the ferrite/steel work piece as well as maps of the microstructural changes occurring in the near-surface *** found that blunt abrasives combined with elevated temperatures have the greatest and most complex impact on near-surface microstructure and stresses,as multiple processes are in mutual competition here.

关键词： large-scale molecular dynamics surface quality microstructure Revolutions per minute-Synchronous Grinding(RPM-Synchronous Grinding) tool wear

Preparation of Pure Copper Powder from Acidic Copper Chloride Waste Etchant

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Journal of Materials Science & Technology 2008年第1期24卷 141-142页

作者： h.S.hong M.S.Kong J.K.Ghu J.K.Lee h.G.Suk Plant Engineering Center.institute for Advanced Engineering Yongin 449-863 Korea Dept. of Advanced Mater. Eng. Korea Polytechnic University Shihung 429-793 Korea Nano-surface Treat. Tech. Team Korea Inst. of Industrial Technology Incheon 463-130 Korea Dept. of Mater. and Met. Eng. Kangwon National University Samcheok 245-711 Korea

The method for the recycling of copper from copper chloride solution was developed. This process consists of extraction of copper, purification and particle size reduction. in the first step, reductive metal scraps were added to acidic copper chloride waste enchants produced in the PCB industry to obtain copper powder. Composition analysis showed that this powder contained impurities such as Fe, Ni, and water. So, drying and purification were carried out by using microwave and a centrifugal separator. Thereby the copper powder had a purity of higher than 99% and spherical form in morphology. The copper powder size was decreased by ball milling.

关键词： Copper chloride liquid waste Printed circuit board (PCB), Liquid waste highpurity copper powder

The Photon Polarization Parameter of 2h（n, γ）3h reaction with inclusion of the Electric Quadrupole Contribution

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Chinese Physics Letters 2014年第9期31卷 32-35页

作者： h. Sadeghi M. Mosavi-Khansari Department of Physics Faculty of Science Arak University Arak 8349-8-38156 Iran

We use effective field theory （EFT） for the calculation of neutron-deuteron radiative capture at very low energies. We present here the use of EFT to calculate a low-energy photo-nuclear observable in three-body systems, the photon polarization parameter and and fore-aft asymmetry at thermal neutron energies up to next-to-next to leading order （N2 LO）, with inclasion of the electric quadrupole contribution. The photon polarization parameter in total is found to be Rc = -0.421±0.003 and is in good agreement with the other modern theoretical calculations based on modern nucleon-nucleon potentials. in comparison with our previous work, a satisfactory agreement with the available experimental data is found by inclusion of the electric quadrupole contribution.

关键词： PhOTONS -- Polarization RESEARCh FiELD theory (Physics) NEUTRON-deuteron interactions QUADRUPOLES ThREE-body problem (Physics)

Smelling fit： scent marking exposes parasitic infection status in the banded mongoose

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Current Zoology 2017年第3期63卷 237-247页

作者： Jessica MiTChELL Michael A. CANT Emma i.K. ViTiKAiNEN hazel J. NiChOLS School of Natural Sciences and Psychology Liverpool John Moores University Liverpool L3 AF UK Centrefor Ecology and Conservation University of Exeter Penryn Campus TRIO 9FE UK

Preference for uninfected mates is presumed beneficial as it minimizes one＇s risk of contracting an infection and infecting one＇s offspring. in avian systems, visual ornaments are often used to indi- cate parasite burdens and facilitate mate choice. however, in mammals, olfactory cues have been proposed to act as a mechanism allowing potential mates to be discriminated by infection status. The effect of infection upon mammalian mate choice is mainly studied in captive rodents where ex- perimental trials support preference for the odors of uninfected mates and some data suggest scent marking is reduced in individuals with high infection burdens. Nevertheless, whether such effects occur in nonmodel and wild systems remains poorly understood. here, we investigate the interplay between parasite load （estimated using fecal egg counts） and scent marking behavior in a wild population of banded mongooses Mungos mungo. Focusing on a costly protozoan parasite of the genus isospora and the nematode worm Toxocara, we first show that banded mongooses that engage in frequent, intensive scent marking have lower isospora loads, suggesting marking behavior may be an indicator trait regarding infection status. We then use odor presentations to demonstrate that banded mongooses mark less in response to odors of opposite sexed individuals with high isospora and Toxocara loads. As both of these parasites are known to have detrimental effects upon the health of preweaned young in other species, they would appear key targets to avoid during mate choice. Results provide support for scent as an important ornament and mechanism for advertising parasitic infection within wild mammals.

关键词： isospora olfaction parasite scent scent preferences Toxocara.

Simple, Selective, and Sensitive Spectrophotometric Method for Determination of Trace Amounts of Nickel(Ⅱ), Copper (Ⅱ), Cobalt (Ⅱ), and iron (Ⅲ) with a Novel Reagent 2-Pyridine Carboxaldehyde isonicotinyl hydrazone

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Chemical Research in Chinese Universities 2008年第2期24卷 143-147页

作者： Sajid h. Guzar JiN Qin-han institute of Miniature Analytical instrumentation College of Chemistry Jilin University Changchun 130021 P. R. China Research Center of instrumentation Zhejiang University Hangzhou 310058 P. R. China

A selective and sensitive reagent of 2-pyridine carboxaldehyde isonicotinyl hydrazone（2-PYAiNh） was synthesized and studied for the spectrophotometric determination of nickel, copper, cobalt, and iron in detail. At a ph value of 7.0, 9,0, 9.0, and 8.0, respectively, which greatly increased the selectivity; nickel, copper, cobalt, and iron reacted with 2-PYAiNh to form a 1：2 yellow-orange, 1：2 yellow-green, 1：2 yellow and 1：1 yellow complexes, with absorption peaks at 363, 352, 346, and 359 nm, respectively. Under the optimal conditions, Beer＇s law was obeyed over the ranges of 0.01-1.4, 0.01-1.5, 0.01-2.7, and 0.01-5.4 mg/L respectively. The apparent molar absorptivity and Sandell＇s sensitivities were 8.4×10^4, 5.2×10^4, 7.1×10^4, and 3.9×10^4 L·mol^-l·cm^-1, respectively, and 0.00069, 0.0012, 0.00078, and 0.0014 μg·cm2, respectively. The detection limits were found to be 0.001, 0.002, 0.003, and 0.01 mg/L, respectively. The detailed study of various interfering ions to make the method more sensitive was carried out and selective and several real samples were analyzed with satisfactory results.

关键词： Copper(Ⅱ) Nickel(Ⅱ) Cobalt(Ⅱ) iron(Ⅲ) 2-Pyridine carboxaldehyde isonicotinyl hydrazone(2-PYAiNh) Spectrophotometry

iNVESTiGATiON OF PhOTOELECTROChROMiC ThiN FiLM AND DEViCE

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Acta Metallurgica Sinica(English Letters) 2005年第3期18卷 275-279页

作者： M.J.Chen h.Shen CollegeofSciences SouthChinaAgricultureUniversityGuangzhou510642China CollegeofPhysicsandEngineering ZhongshanUniversityGuangzhou510275China

Photoelectrochromic device is a combination of dye-sensitized solar cells and el ectrochromic WO3 layers. Ectrochroelmic WO3 layer and TiO2 layer had been prepar ed by the sol-gel process, then be assembled to pohotoelectrochromic device. The effects of heating temperature on photoelectrochromic were investigated. The re sults showed that thin films prepared by dip-coating and spin-coating had good f ilm quality and the device made by the method mentioned in the paper had good ph otoelectrochromic properties.

关键词： WO3 ,TiO2 photoelectrochromic sol-gel