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Hydrogenation, structure and magnetic properties of.La(f._(0.91)Si_(0.09))_(13) hydrides and deuterides

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Chinese Physics B 2011年第6期20卷 426-430页

作者：王志翠何伦华 f. Cuevas m. Latroche 沈俊王芳卫 Beijing National Laboratory f.r Condensed matter Physics Institute of Physics Chinese Academy of Sciences Chimie metallurgique des Terres Rares ICMPE-CNRS UMR 7182 2-8 rue Henri Dunant 94320 Thiais France Technical Institute of.Physics and Chemistry Chinese Academy of Sciences

Hydrogenation, crystal structure and magnetic properties of.La（f.0.91Si0.09）13H（D）y have been studied by pressure-composition isotherms （PCI）, X-ray dif.raction （XRD）, dif.erential scanning calorimetry （DSC） and magnetization measurements. The maximum absorption capacity is f.und to be 1.9 H（D） atoms per f.rmula unit as a solid solution. All hydrides and deuterides crystallize in the NaZnl3-type cubic structure with the lattice parameter increasing linearly with H（D） concentration. The H（D） absorption enhances the Curie temperature signif.cantly. The magnetic entropy change of.the highly H-absorbed compound La（f.o.91Sio.09）13H1.81 reaches -26 J/kg-K under a magnetic f.eld change of.5 T near the Curie temperature Tc =350 K. No observable isotope ef.ect seems to imply that only the magnetovolume ef.ect is responsible f.r the strong interplay between magnetism and lattice.

关键词： magnetocaloric ef.ect magnetic entropy change isotope ef.ect

Application of.artif.cial neural networks f.r predicting the impact of.rolling dynamic compaction using dynamic cone penetrometer test results

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Journal of.Rock mechanics and Geotechnical Engineering 2017年第2期9卷 340-349页

作者： R.A.T.m. Ranasinghe m.B. Jaksa Y.L. Kuo f. Pooya Nejad School of.Civil Environmental and Mining EngineeringUniversity of AdelaideAdelaideAustralia

Rolling dynamic compaction(RDC),which involves the towing of.a noncircular module,is now widespread and accepted among many other soil compaction ***,to date,there is no accurate method f.r reliable prediction of.the densif.cation of.soil and the extent of.ground improvement by means of.*** study presents the application of.artif.cial neural networks(ANNs) f.r a priori prediction of.the ef.ectiveness of.*** models are trained with in situ dynamic cone penetration(DCP) test data obtained f.om previous civil projects associated with the 4-sided impact *** predictions f.om the ANN models are in good agreement with the measured f.eld data,as indicated by the model correlation coef.icient of.approximately *** is concluded that the ANN models developed in this study can be successf.lly employed to provide more accurate prediction of.the perf.rmance of.the RDC on a range of.soil types.

关键词： Rolling dynamic compaction(RDC) Ground improvement Artif.cial neural network(ANN) Dynamic cone penetration(DCP) test

A comparative study of.the electrooxidation of.C1 to C3 aliphatic alcohols on Ni modif.ed graphite electrode

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Science China Chemistry 2012年第9期55卷 1819-1824页

作者： JAf.RIAN m. mIRZAPOOR A. DANAEE I. SHAHNAZI Sangachin A.A. GOBAL f. Departement of.Chemistry K.N.Toosi University of TechnologyTehranIran Abadan f.culty of.Petroleum Engineering Petroleum University of TechnologyAbadanIran Departement of.Chemistry Sharif University of TechnologyTehranIran

Nickel modif.ed graphite electrodes （G/Ni） prepared by galvanostatic deposition were examined f.r their redox process and electrocatalytic activities towards the oxidation of.methanol, ethanol, 1-propanol and 2-propanol in alkaline solutions. The methods of.cyclic voltammetry （CV）, ehronoamperometry （CA） and impedance spectroscopy （EIS） were employed. In CV studies, the electrochemical response, peak current varied in the order of.meOH 〉 EtOH 〉 1-PrOH 〉 2-PrOH. Under the CA regime, a higher catalytic rate constant obtained f.r methanol oxidation was in agreement with CV measurements. Lower charge transf.r resistance was obtained f.r low carbon alcohols oxidation and signif.cantly higher exchange current density was obtained f.r methanol oxidation.

关键词： alcohols electrocatalytic nickel modif.ed electrode equivalent circuit

mobility of.Arsenic and Heavy metals in a Sandy-Loam Textured and Carbonated Soil

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Pedosphere 2009年第2期19卷 166-175页

作者： I. GARC íA m. DIEZ f. mART íN m. SImóN C. DORRONSORO Departamento Edaf.logia y Quimica Agricola CITE IIB Carretera Sacramento s/n 04120 University of Almeria (Spain) Departamento Edaf.logia y Quimica Agricola Campus Fuentenueva s/n 18002 University of Granada (Spain)

The continued ef.ect of.the pyrite-tailing oxidation on the mobility of.arsenic, lead, zinc, cadmium, and copper was studied in a carbonated soil under natural conditions, with the experimental plot preserved with a layer of.tailing covering the soil during three years. The experimental area is located in Southern Spain and was af.ected by a pyrite-mine spill. The climate in the area is typically mediterranean, which determines the rate of.soil alteration and element mobility. The intense alteration processes that occurred in the soil during three years caused important changes in its morphology and a strong degradation of.the main soil properties. In this period, lead concentrated in the f.rst 5 mm of.the soil, with concentrations higher than 1500 mg kg?1, mainly associated to the neof.rmation of.plumbojarosite. Arsenic was partially leached f.om the f.rst 5 mm and mainly concentrated between 5–10 mm in the soil, with maximum values of.1239 mg kg-1; the retention of.arsenates was related to the neof.rmation of.iron hydroxysulf.tes (jarosite, schwertmannite) and oxyhydroxides (goethite, f.rrihydrite), both with a variable degree of.crystallinity. The mobility of.Zn, Cd, and Cu was highly af.ected by pH, producing a stronger leaching in depth; their retention was related to the f.rms of.precipitated aluminium and, in the case of.Cu, also to the neof.rmation of.hydroxysulf.te.

关键词： arsenic heavy metals oxidation pyrite-tailing soil

Thermo-optic characterization of.KDP single crystals by a modif.ed Snarmont setup f.r electro-optic modulation system

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Chinese Optics Letters 2009年第7期7卷 632-639页

作者： H. L. Saadon m. A. Rahma Ali f. marhoon N. Thof.nous m. Aillerie Department of.Inf.rmatics and Telecommunications Optoelectronics Group University of AthensPanepistimiopolis Ilisia GR-157 84 Athens Greece Department of.Physics College of Science University of BasrahBasrah Iraq Laboratoire matriaux Optiques Photonique et Systmes UMR CNRS 7132 Universit de Metz et Suplec2 rue E. Belin 57070 Metz France

f.r our KDP crystal orientation, various tbermo-optic （TO） and relevant temperature-dependence param- eters are def.ned, presented, and studied in the f.amework of.a transverse and a longitudinal electro-optic （EO） modulation systems. This study is based on the concept of.the so-called opto-electrical bias （~） ap- plied to the system. f.r both of.the above EO-modulation systems, a set of.original equations is extracted and investigated with regard to each of.the more important TO or temperature coef.icients. Using these equations, f.r these parameters the role of.the transverse conf.guration is examined in comparison with its corresponding longitudinal conf.guration. A comparison is done with other orientation of.the same KDP crystal.

关键词： narmont setup f.r electro-optic modulation system Thermo-optic characterization of.KDP single crystals by a modif.ed S KDP

Bioaccumulation of.metals in human blood in industrially contaminated area

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Journal of.Environmental Sciences 2011年第12期23卷 2069-2077页

作者： f. Akbar Jan m. Ishaq S. Khan m. Shakirullah S. m. Asim I. Ahmad f.zal mabood Institute of.Chemical Sciences University of.Peshawar 25120 Khyber-Pukhtunkhwa Pakistan Department of.Environmental Sciences University of Peshawar Peshawar Pakistan Department of.Statistics University of.Peshawar Peshawar Department of.Biological-Sciences ＆ Chemistry University of Nizwa Nizwa Oman

Heavy metals were analyzed in dif.erent f.ods crops, milk, meat and blood samples collected f.om dif.erent age group subjects such as children （1–12 years）, adolescent （12–18 years）, adults （18–45 years） and old age （above 45 and 55 years f.r males and f.males, respectively） f.om polluted and relatively less polluted areas. The results revealed that the consumption of.contaminated f.od crops, meat and milk have signif.cantly increased the concentrations of.selected metals in the human blood. Cu, Zn and mn concentrations were signif.cantly higher （p 0.05） in the blood samples collected f.om the polluted area as compared to control area. Old people had accumulated high concentrations of.metals as compared to the younger ones within the same area. males accumulated higher concentrations of.metals as compared to f.males.

关键词： bioaccumulation heavy metals blood contaminated meat milk f.rage grass

Delayed Ionization and Delayed Detachment in molecules and Clusters

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Chinese Journal of.Chemical Physics 2009年第2期22卷 162-170页

作者： f. Lépine B. Baguenard B. Concina m. A. Lebeault C. Bordas Université de Lyon F-69522 Lyon France Université Lyon 1 Villeurbanne CNRS UMR 5579 LASIM

The evolution of.a molecular system excited above its ionization threshold depends on a number of.parameters that include the nature of.the excited states and their couplings to the various continua. The general nature of.the processes governing this evolution depends also essentially on the complexity of.the molecule, more precisely on its size, density of.states, and strength of.the couplings among the various internal degrees of.f.eedom. In this paper we address the question of.the transition between autoionization that prevails in small molecules, and delayed ionization occurring in larger molecules or clusters. This transition is illustrated by autoionization of.Na2 Rydberg states on one hand, delayed ionization in f.llerene C60, and delayed detachment in small cluster anions on the other hand. All processes are studied in the case of.nanosecond laser excitation, corresponding to a rather slow deposition of.the internal energy.

关键词： Autoionization Autodetachment Thermionic emission

The Quotient Category of.a Graded morita-Takeuchi Context

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Acta mathematica Sinica,English Series 2006年第1期22卷 123-130页

作者： f. CASTANO IGLESIAS C. NASTASESCU Departamento de Estadistica y matemdtica Aplicada Universidad de Almeria 04120 Almeria Spain f.cultatea de matematica Str. Academiei 14 RO-70109 Bucharest Romania

In this paper, we of.er a graded equivalence between the quotient categories def.ned by any graded morita-Takeuchi context via certain modif.cations of.the graded cotensor f.nctors. As a consequence, we show a commutative diagram that establish the relation between the closed objects of.the categories gr^c and m^C, where C is a graded coalgebra.

关键词： Graded coalgebra Graded morita context Quotient category

The Zariski Topology on the Second Spectrum of.a module

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Algebra Colloquium 2014年第4期21卷 671-688页

作者： H. Ansari-Toroghy f. f.rshadif.r Department of.Pure mathematics Faculty of Mathematical Sciences University of Guilan P.O. Box 41335-19141 Rasht Iran

Let R be a commutative ring and m be an R-module. The second spectrum Spec^S（m） of.m is the collection of.all second submodules of.m. We topologize Spec^S（m） with Zariski topology, which is analogous to that f.r Spec（R）, and investigate this topolog- ical space. f.r various types of.modules m, we obtain conditions under which Spec^S（m） is a spectral space. We also investigate Specs （m） with quasi-Zariski topology.

关键词： second submodule second spectrum cotop module spectral space Zariskitopology