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Prediction of.Soil Depth f.om Digital Terrain Data by Integrating Statistical and Visual Approaches

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Pedosphere 2010年第3期20卷 361-367页

作者： f. m. ZIADAT International Center f.r Agricultural Research in the Dry Areas (ICARDA) P.O. Box 5466Aleppo (Syria)

Inf.rmation about the spatial distribution of.soil attributes is indispensable f.r many land resource management applications; however, the ability of.soil maps to supply such inf.rmation f.r modern modeling tools is questionable. The objectives of.this study were to investigate the possibility of.predicting soil depth using some terrain attributes derived f.om digital elevation models （DEms） with geographic inf.rmation systems （GIS） and to suggest an approach to predict other soil attributes. Soil depth was determined at 652 f.eld observations over the A1-muwaqqar Watershed （70 km2） in Jordan. Terrain attributes derived f.om 30-m resolution DEms were utilized to predict soil depth. The results indicated that the use of.multiple linear regression models within small watershed subdivisions enabled the prediction of.soil depth with a dif.erence of.50 cm f.r 77% of.the f.eld observations. The spatial distribution of.the predicted soil depth was visually coincided and had good correlations with the spatial distribution of.the classes amalgamating three terrain attributes, slope steepness, slope shape, and compound topographic index. These suggested that the modeling of.soil-landscape relationships within small watershed subdivisions using the three terrain attributes was a promising approach to predict other soil attributes.

关键词： compound topographic index digital elevation model GIS watershed

modelling of.Gettering by mechanical Damage of.metallic Impurities in Silicon

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Chinese Physics Letters 2006年第11期23卷 3058-3060页

作者： f. Ayad m. Remram Department of.Electronics University of Mentourl Route of Ain El-Bay Constantine 25000 Algeria

Reducing the concentration of.the metallic impurities present in silicon-based electronic components plays a vital role in manuf.ctures. Gettering by induced mechanical damage is one of.the methods used in neutralizing these impurities. To simulate this type of.gettering, we explicitly include the role of.the traps due to mechanical damage, based on the mechanism of.kick-out. In our model, we choose the essential parameters including concentration of.impurities, thickness, temperature, time, etc. The dif.usion coef.icient and equilibrium concentration of.the silicon interstitials estimated f.om the literature have been adjusted to be in good agreement with the experimental data.

关键词： DIf.USION GOLD

Study of.the Reaction of.5-Aryl-7-hydrazino-2-phenylpyra- zolo[1,5-c]pyrimidines with 1,3-Dicarbonyl Compounds

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Chinese Journal of.Chemistry 2011年第11期29卷 2451-2460页

作者： Atta, Kamal f. m. Chemistry Department Faculty of Science Alexandria University lbrahimia P. O. Box 426 Alexandria 21321 Egypt

A novel synthetic method f.r the preparation of.5-aryl-7-（3,5-dimethyl-lH-pyrazol-l-yl）-2-phenylpyra- zolo[1,5-c]-pyrimidines and 1-（5-aryl-2-phenylpyrazolo[1,5-c]pyrimidin-7-yl）-3-methyl-lH-pyrazol-5-ols is provided by condensative cyclization of.5-aryl-7-hydrazino-2-phenylpyrazolo[1,5-c]pyrimidines with 1,3-dicarbonyl compounds. The study of.the more reactive position f.r electrophilic substitusion reactions on such ring system was also achieved.

关键词： cyclization electrophilic substitution pyrazolylpyrazolopyrimidine IR NmR mass spectrometry

Bound states of.the Dirac equation with position-dependent mass f.r the Eckart potential

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Chinese Physics B 2013年第1期22卷 62-67页

作者： Bahar m. K. Yasuk f. Department of.Physics Erciyes University Department of.Physics Karamanoglu Mehmetbey University

Studying with the asymptotic iteration method, we present approximate solutions of.the Dirac equation f.r the Eckart potential in the case of.position-dependent mass. The centrif.gal term is approximated by an exponen... 详细信息

关键词： Dirac equation position-dependent mass Eckart potential asymptotic iteration method

Combined Ef.ect of.magnetic f.eld and Thermal Dispersion on a Non-Darcy mixed Convection

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Journal of.Thermal Science 2011年第3期20卷 276-282页

作者： m. f. EI-Amin Shuyu Sun Computational Transport Phenomena Laboratory （CTPL） Division of Physical Sciences and Engineering （PSE）King Abdullah University of Science and Technology （KAUST） Thuwal 23955-6900 Jeddah Kingdom of Saudi Ara-bia mathematics Department Faculty of Science South Valley University Aswan 81528 EGYPT

This paper is devoted to investigate the inf.uences of.thermal dispersion and magnetic f.eld on a hot semi-inf.nite vertical porous plate embedded in a saturated Darcy-f.rchheimer-Brinkman porous medium. The coef.icient of.thermal dif.usivity has been assumed to be the sum of.the molecular dif.usivity and the dynamic dif.usivity due to mechanical dispersion. The ef.ects of.transverse magnetic f.eld parameter (Hartmann number Ha), Reynolds number Re (dif.erent velocities), Prandtl number Pr (dif.erent types of.f.uids) and dispersion parameter on the wall shear stress and the heat transf.r rate are discussed.

关键词： Thermal dispersion non-Darcy convection magneto-hydro-dynamics porous media geothermal systems

Prof.le and Secondary f.ow Losses in a High-Lif. LPT Blade Cascade at Dif.erent Reynolds Numbers under Steady and Unsteady Inf.ow Conditions

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Journal of.Thermal Science 2012年第6期21卷 483-491页

作者： Satta f. Simoni D. Ubaldi m. Zunino P. Bertini f. DImSET-Università di Genova Via Montallegro 1I-16145 GenovaItaly Avio S.p.A. Viale I Maggio 56I-10040 Rivalta(TO)-Italy

The aerodynamic f.ow f.eld downstream of.a Low-Pressure High-Lif.(HL)turbine cascade has been experimentally investigated f.r dif.erent Reynolds numbers under both steady and unsteady inf.ows,in order to analyse the cascade perf.rmance under real engine operating *** Reynolds number has been varied in the range 100000mits are typical of.cruise and take-of./landing conditions,*** ef.ects induced by the incoming wakes at the reduced f.equency f.=0.62 on both prof.le and secondary f.ow losses have been *** pressure,velocity and secondary kinetic energy distributions at the downstream tangential plane have been measured by means of.a miniaturized 5-hole *** quantities provide inf.rmation on both blade wake and secondary f.ow structures(passage and horse-shoe vortices).The analysis of.the results allows the evaluation of.the aerodynamic perf.rmance of.the HL f.ont-loaded blade in terms of.both prof.le and secondary losses.

关键词： prof.le losses secondary f.ow losses high-lif. prof.es unsteady inf.ow LPT blade.

Plasma and Gaseous Nitrocarburizing of.C60W Steel f.r Tribological Applications

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材料热处理学报 2004年第5期25卷 338-342页

作者： m. mirjani f. Ashraf.zadeh A. Shaf.ei Iranian Surf.ce Research & Engineering Centre (ISREC) Isfahan Iran Dept. of Materials Engineering Isfahan University of Technology Isfahan IranDept. of Materials Engineering Isfahan University of Technology Isfahan Iran.

A comparison has been made between plasma and gas nitrocarburizing processes f.r C60W steel in terms of.structural f.atures of.the layers and the tribological properties of.the specimens. Gaseous treatments were perf.rmed in a sealed quench industrial f.rnace in optimized process cycles. f.r plasma nitrocarburizing, a semi - industrial size unit was operated at a range of.process parameters. Experimental results indicate that increasing the treatment time increases the thickness of.the compound layer but lowers the wear resistance. Plasma treatment produced a more ef.ective case depth compared with gaseous process, providing a better unif.rmity. Analysis of.X-ray dif.raction patterns indicated that the compound layer in gas nitrocarburizing consisted of.both e and y’ phases, whereas in plasma nitrocarburizing the e phase was not detected.

关键词： C60W钢等离子氮碳共渗气态氮碳共渗摩擦学

Electron Acceleration by microwave Radiation Inside a Rectangular Waveguide

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Plasma Science and Technology 2011年第3期13卷 357-361页

作者： B. f. mOHAmED A.m. GOUDA Plasma Physics Department N.R.C. Atomic Energy Authority Cairo Egypt

Electron dynamics in the f.elds associated with a transverse magnetic （Tm） wave propagating inside a rectangular waveguide is analytically studied. The relativistic momentum and energy equations f.r an electron are solved, which was injected initially along the propagation direction of.the microwave. Expressions of.the acceleration gradient and def.ection angle are obtained. In principle, it is shown that the electron can be accelerated in this condition and there is no def.ection when the electron is injected f.om the centre of.the waveguide f.ont. However, it is f.und that the acceleration gradient and def.ection angle depend strongly on the parameters of.the microwave （intensity, f.equency, etc.） and the dimensions of.the waveguide.

关键词： waveguide electron acceleration polarized microwave

An empirical study on vortex-generator insert f.tted in tubular heat exchangers with dilute Cu–water nanof.uid f.ow

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Chinese Journal of.Chemical Engineering 2016年第6期24卷 728-736页

作者： m. Khoshvaght-Aliabadi m.H. Akbari f. Hormozi Department of.Chemical Engineering Shahrood Branch Islamic Azad University Shahrood lran School of.Chemical Petroleum and Gas Engineering Semnan University Semnan lran

The heat transf.r enhancement(HTE) in tubular heat exchangers f.tted with vortex-generator(VG) inserts is experimentally investigated. The studied f.ur parameters and ranges are: winglets-pitch ratio(1.33, 2.67, and 4),winglets-length ratio(0.33, 0.67, and 1), winglets-width ratio(0.2, 0.4, and 0.6), and Reynolds number(5200to 12200). The testing f.uids are the water and Cu–water nanof.uid at the volumetric f.action of.0.2%. The results obtained on HTE, pressure drop, and perf.rmance evaluation criterion(PEC) are compared with those f.r water in a smooth tube. It is f.und that the VG inserts with lower winglets-pitch ratio and higher winglets-length/width ratios present higher values of.HTE and pressure drop. Over the range studied, the maximum PEC of.1.83 is detected with the Cu–water nanof.uid inside the tube equipped with a VG insert at the winglets-width ratio of..6 f.r the maximum Reynolds number, when the heat transf.r rate and pressure drop are 1.24 times and 2.03 times of.those in the smooth tube. Generalized regression equations of.the Nusselt number, f.iction f.ctor, and PEC are presented f.r the tubular heat exchangers with the VG inserts f.r both water and Cu–water *** is concluded that the main advantage of.the VG inserts is their simple f.brication and considerable perf.rmance, particularly at higher Reynolds number.

关键词： Heat transf.r enhancementVortex-generator insertNanof.uid Turbulent f.owCorrelation