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Abkhandari (Aquifer Management): a Green Path to the Sustainable Development of Marginal Drylands

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Journal of Mountain Science 2005年第3期2卷 233-243页

作者： sayyed ahang kowsar Fars Research Center for Agriculture and Natural Resources P.O. Box 71365-458 Shiraz I.R. Iran

Recurrent droughts and occasional floods are the facts of life in drylands. The presence of innumerable societies in deserts is the living proof that even the extremely dry environments are livable; the secret is how to adapt to the situation. Floodwater management, the most important art of sedentarized desert dwellers, is the secret of living with deserts. Floodwater irrigation alone, or in combination with the artificial recharge of groundwater （ARG）, has sustained the Persians for millennia. The scientists at the kowsar Floodwater Spreading and Aquifer Management Research, Training and Extension Station in the Gareh Bygone Plain have been working since January 1983 to revive this ancient art and upgrade it to the level of science. A summary of important findings is provided as follows： 1. Debris cones and coarse alluvial fans are the best places for the ARG as they provide the potential aquifer for groundwater storage. The recharged water may be used for irrigation on the lower lying, fine alluvium; 2. Flood is not a proverbial curse but a blessing in disguise, and the turbid floodwater is the best resource for the sustainable development of drylands; 3. Translocation of fine clay minerals eventually makes the vadose zone impermeable. Planting deep-rooted, drought-resistent trees and shrubs, and introducing sowbugs （Hemilepistus shirazi Schuttz） are reliable methods to increase infiltration rate and the saturated hydraulic conductivity of the ARG systems; 4. The moving sand stabilization is best achieved by spreading turbid floodwater onto them. Establishing of living windbreaks and planting of fodder trees and shrubs turn a sand menace into a verdant pasture; 5. The 10 year average of native forage yield in the ARG systems has been 445 kg·ha^-1·year^-1 as opposed to 92 kg·ha^-***^-1 for the control. At 4×4 m^2 spacing, Atriplex lentiformis （Torr.） Wats. can annually yield 1500 kg ha^-1 of dry matter and support 3 heads of sheep; 6. The stem- and fuel wo

关键词： Floodwater artificial recharge of groundwater (ARG) drylands sustainable development

Influence of erbium on structural,and charged particles,photons,and neutrons shielding properties of Ba_(1-x)Er_(x)SnO_(3) perovskite ceramics

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Journal of Rare Earths 2024年第4期42卷 724-732页

作者： M.K.h.Hamad Nidal Dwaikat M.H.A.Mhareb M.I.sayyed R.M.Hamad Y.S.M.Alajerami M.A.Almessiere Gameel Saleh Ahmad Hussein Alomari K.A.Ziq Department of Basic Sciences School of Social and Basics SciencesAl Hussein Technical UniversityKing Abdullah II St 242Amman11831Jordan Department of Physics College of Engineering and PhysicsInterdisciplinary Research Center for Advanced MaterialsKing Fahd University of Petroleum&MineralsDhahran31261Saudi Arabia Department of Physics College of ScienceImam Abdulrahman Bin Faisal UniversityP.O.Box 1982Dammam31441Saudi Arabia Basic and Applied Scientific Research Center Imam Abdulrahman Bin Faisal UniversityP0.Box 1982Dammam31441Saudi Arabia Department of Physics Faculty of ScienceIsra UniversityAmman11622Jordan Department of Nuclear Medicine Research Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityPo.Box 1982Dammam31441Saudi Arabia Medical Imaging Department Applied Medical Sciences FacultyAl Azhar University-Gaza CityPo.Box 1277Palestine Department of Biophysics Institute for Research and Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityPo.Box1982Dammam 31441Saudi Arabia Department of Biomedical Engineering College of EngineeringImam Abdulrahman Bin Faisal UniversityPo.Box 1982Dammam31441Saudi Energy&Minerals Regulatory Commission Amman11821Jordan

Five perovskite ceramics samples of Ba_(1-x)Er_(x)SnO_(3) with x=0.00,0.05,0.10,0.15,and 0.20 were synthesized using the conventional solid-state reaction *** prepared samples were characterized by X-ray diffraction(XRD),Fourier transforms infrared(FTIR),and UV-Vis *** shielding properties against ionizing radiation were also *** XRD analysis shows the perovskite cubic structure as the major phase in all *** FTIR reveals a distinctive band around 614-620 cm^(-1) ascribed to the antisymmetric O-Sn-O ***-Vis spectroscopy was used to determine the bandgap according to diffuse reflectance,and the results display a fixed enhancement in the bandgap from 3.2 to 3.3 eV for all ***-ray shielding properties of the synthesized samples were experimentally measured and compared with XCOM computational *** relative differences(Δ,%)between experimental and theo retical values are low and fall within the 0.446%-7.10%*** addition of Er leads to the enhanced density,neutron,and gamma shielding *** contrast,charged particles’shielding parameters gradually reduce with rising Er *** results suggest that Ba_(1-x)Er_(x)SnO_(3) samples can be used in different radiation shielding applications.

关键词： Perovskite Ceramics Gamma ray shielding Mass stopping power Rare earths

Comparison of effective parameters for copper powder production via electrorefining and electrowinning cells and improvement using DOE methods

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International Journal of Minerals,Metallurgy and Materials 2011年第6期18卷 731-740页

作者： Ebrahim Akbarzadeh sayyed Esmaeil Shakib Department of Materials Science and Metallurgical Engineering Shahid Bahonar University of Kerman

The influences of cupric ion concentration （5-35 g/L）,current density （500-2000 A/m2）,circulation rate of the electrolyte solution （15-120 mL/min）,and temperature （25-60℃） on the physical and chemical properties of copper powders obtained in electrolysis cells were *** industrial processes,electrorefining （ER） cells with a synthetic electrolyte and electrowinning （EW） cells with an original solution of coppermineral leaching,were utilized to produce copper ***,the statistical full factorial method of design of experiments （DOE） was employed to investigate the interaction or the main effects of *** results show that increasing the copper concentration and temperature can increase the grain size,apparent density,and electrical energy *** the other hand,increasing the current density and circulation rate of the electrolyte can decrease *** production process is optimized via DOE to control the interactive and main effects to produce copper powders with favorable properties.

关键词： copper powders electrorefining electrowinning grain size apparent density

Model for increased efficiency of CIGS solar cells by a stepped distribution of carrier density and Ga in the absorber layer

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Science China(Physics,Mechanics & Astronomy) 2013年第8期56卷 1533-1541页

作者： SHARBATI Samaneh KESHMIRI sayyed-Hossein Department of Electrical Engineering Ferdowsi University of Mashhad

In this paper, several structures for multilayer Cu(In1-xGax) Se2 (CIGS) thin film solar cells are proposed to achieve high conversion efficiency. All of the modeling and simulations were based on the actual data of experimentally produced CIGS cells reported in the literature. In standard CIGS cells with a single absorber layer, the effects of acceptor density and Ga content on device performance were studied, and then optimized for maximum conversion efficiency. The same procedure was performed for cells with two and three sectioned CIGS absorber layers in which Cu and/or Ga contents were varied within each consecutive section. This produces an internal additional electric field within the absorber layer, which resulted in an increase in carrier collection for longer wavelength photons, and hence, improvement in the conversion efficiency of the cell. An increase of approximately 3% in efficiency is predicted for cells with two layer absorbers. For multilayer cells in which Cu and Ga distribution were stepped simultaneously, the improvement could be approximately 3.5%. This improvement is due to; enhanced carrier collection for longer-wavelength photons, and reduced recombination at the heterojunction and back regions of the cell. These results are confirmed by the physics of the cells.

关键词： Cu (In Ga)Se2 (CIGS) multilayer thin film solar cell quantum efficiency

Flood basalt hosted palaeosols:Potential palaeoclimatic indicators of global climate change

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Geoscience Frontiers 2014年第6期5卷 791-799页

作者： M.R.G.sayyed Department of Geology Poona College (University of Pune)CampPune 411 001MaharashtraIndia

Since continental sediments （in addition to the marine geological record） offer important means of deciphering environmental changes, the sediments hosted by the successive flows of the continental flood basalt provinces of the world should be treasure houses in gathering the palaeoclimatic data. Palaeosols developed on top of basalt flows are potentially ideal for palaeoenvironmental reconstructions because it is easy to determine their protolith geochemistry and also they define a definite time interval. The present paper summarizes the nature of the basalt-hosted palaeosols formed on the flood basalts provinces from different parts of the ~lobe havin~ different ages.

关键词： Continental flood basalts Palaeosols Weathering Palaeoclimates Global change

Bayesian Regularization Neural Networks for Prediction of Austenite Formation Temperatures(A_(c1) and A_(c3))

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Journal of Iron and Steel Research International 2014年第2期21卷 246-251页

作者： Masoud RAKHSHKHORSHID sayyed-Amin TEIMOURI SENDESI Department of Mechanical Engineering Birjand University of Technology Department of Mechanical Engineering Roudbar BranchIslamic Azad University

A neural network with a feed forward topology and Bayesian regularization training algorithm is used to predict the austenite formation temperatures （At1 and A13） by considering the percentage of alloying elements in chemical composition of steel. The data base used here involves a large variety of different steel types such as struc- tural steels, stainless steels, rail steels, spring steels, high temperature creep resisting steels and tool steels. Scatter diagrams and mean relative error （MRE） statistical criteria are used to compare the performance of developed neural network with the results of Andrew% empirical equations and a feed forward neural network with ＂gradient descent with momentum＂ training algorithm. The results showed that Bayesian regularization neural network has the best performance. Also, due to the satisfactory results of the developed neural network, it was used to investigate the effect of the chemical composition on Ac1 and At3 temperatures. Results are in accordance with materials science theories.

关键词： Bayesian regularization neural network steel chemical composition Ac1 Ae3

Fabrication of Bulk (Fe,Cr)_3Al/Al_2O_3 Intermetallic Matrix Nanocomposite Through Mechanical Alloying and Sintering

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Acta Metallurgica Sinica(English Letters) 2016年第10期29卷 911-919页

作者： sayyed Erfan Aghili Mohammad Hossein Enayati Fathallah Karimzadeh Department of Materials Engineering Isfahan University of Technology

In the present study, （Fe,Cr）3Al/20 vol% A1203 nanocomposite was prepared through mechanochemical reactions during ball milling and successfully bulked using a combination of cold isostatic press and sintering at 1400℃ for 1 h. Two processing approaches were utilized to produce （Fe,Cr）3A1/A1203 nanocomposite： The first was milling of Fe, Cr, AI and Fe203, while the second one was milling of Fe, Cr, Al and Cr203, both in stoichiometric condition, to synthesize （Fe,Cr）3Al/20 vol% Al2O3. Structural changes of powder particles during mechanical alloying were studied by X-ray diffraction. The microstructure and the morphology of powder particles and bulk samples were also studied by scanning electron microscopy and transmission electron microscopy. Microstructural analysis showed that mechanochemical reactions took place during milling, and nanometric Al2O3 was uniformly distributed in the matrix. The results also showed that the second approach required a considerably higher milling time to produce （Fe,Cr）3Al/Al2O3 nanocomposite, as compared to the first one. For this reason, bulk samples were produced from the synthesized nanocomposite in the first approach. The microstructure of the sintered samples consisted of a network structure of （Fe,Cr）3Al and Al2O3 phases with superior mechanical properties.

关键词： Iron aluminide Mechanical alloying Nanocomposite Mechanochemical treatment

Design of an Optical Water Pollution Sensor Using a Single-Layer Guided-Mode Resonance Filter

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Photonic Sensors 2013年第3期3卷 224-230页

作者： Edward SADER Abdallah sayyed-AHMAD Department of Physics Birzeit University Birzeit Palestine

The optical characteristics of a simple, planar, single layer, dielectric Mg-based guided mode resonance filter （GMRF） were investigated by means of rigorous-coupled wave analysis （RCWA）. This filter has great potential for real-life applications, especially as bio- and environmental sensors. The structure of the proposed sensor is compact, and all of its layers can be grown in a single process. In this paper, we present results on the design of a water pollution sensor in the violet region of the visible spectrum. The spectral and angular sensitivities of the sensor for both the transverse electric （TE） and transverse magnetic （TM） polarization modes were estimated and compared for various regions in the violet spectrum. A spectral response characterized with a narrow bandwidth and low reflection side bands was realized by carrying out extensive parameter search and optimization. Optimal spectral and angular sensitivities were found for the sensor with a grating thickness of 100nm in the TM polarized mode where we found them to be 100nm and 40 degrees, per index refraction unit, respectively.

关键词： Diffractive optics guided waves filters sensors spectral sensitivity angular sensitivity

Deactivation studies of nano-structured iron catalyst in Fischer-Tropsch synthesis

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Journal of Natural Gas Chemistry 2010年第3期19卷 333-340页

作者： Ali Nakhaei Pour Mohammad Reza Housaindokht sayyed Faramarz Tayyari Jamshid Zarkesh Department of Chemistry Ferdowsi University of Mashhad Research Institute of Petroleum Industry of National Iranian Oil Company

A nano-structured iron catalyst for syngas conversion to hydrocarbons in Fischer-Tropsch synthesis（FTS） was prepared by micro-emulsion *** of bulk iron phase and phase transformations of carbonaceous species during catalyst deactivation in FTS reaction were characterized by temperature-programmed surface reaction with hydrogen（TPSR-H 2 ）,and XRD *** carbonaceous species on surface and bulk of the nano-structured iron catalysts were completely identified by combined TPSR-H 2 and XRD spectra and which were compared with those recorded on conventional co-precipitated iron *** results reveal that the catalyst deactivation results from the formation of inactive carbide phases and surface carbonaceous species like graphite,and it will be increased when the particle size of iron oxides was reduced in FTS iron catalyst.

关键词： Fischer-Tropsch synthesis iron-based catalyst catalyst deactivation nano-size particles