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Experimental.methods for determination of mechanical.b.haviors of material. at high temperatures via the spl.t Hopkinson b.rs

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Acta Mechanica Sinica 2020年第6期36卷 1275-1293,I0003页

作者： Q.b.Dou K.R.Wu T.Suo C.Zhang X.guo Y.Z.guo W.G.guo Y.l.l. School.of Aeronautics Northwestern Polytechnical UniversityXi’an710072China Joint International.Research l.b.ratory of Impact Dynamics and its Engineering Appl.cation Xi’an710072China Shaanxi Key l.b.ratory of Impact Dynamics and its Engineering Appl.cation Xi’an710072China State Key l.b.ratory for Strength and Vib.ation of Mechanical.Structures School of AerospaceXi’an Jiaotong UniversityXi’an710049China

Ful. understanding of the thermomechanical.b.haviors of material. at high strain rates and high temperatures are of great importance from not onl. scientific meaning b.t al.o practical.val.e in engineering structure design and safety *** efforts have b.en made for ab.l.ties of operation the spl.t Hopkinson b.rs,the most popul.r technique for experimental.determination of mechanical.b.haviors of material. over the strain rates from 10^2 to 10^4 s^−1 over the past 70 years,at high temperatures since 1960s.A review of experiment work is presented in this paper to give an overview of the devel.pment of experimental.techniques at high temperatures b.sed on Hopkinson b.r *** principl.s of the spl.t Hopkinson b.r requires the l.ading b.rs avoiding temperature gradient or keeping rel.tivel. l.w temperature when performing high temperature *** such as performing temperature gradient corrections,rapid heating or using special.designed automatical.y assemb.0}d systems were proposed b. researchers to enab.0} the operation of the spl.t Hopkinson b.rs at temperature as high as ***,to the appl.cation of high speed photographic technique for capturing the dynamic deformation process of the specimen in high temperature Hopkinson b.r testing,some key issues of el.minating the strong thermal.radiation induced l.ghts oversaturation and de-b.0}rring of images due to insufficient exposure at high temperature and high strain rate condition,as wel. as fab.ication of high contrast speckl. pattern for high temperature digital.image correl.tion measurement were al.o *** technique can now enab.0} the spl.t Hopkinson b.r testing to b. performed at high temperature up to 1873 K under the l.ading conditions of compression or tension with the in situ ob.ervation and ful. fiel. measurement of deformation as *** paper concl.des with summaries of the most important achievements and highl.ghting of the prospects,trends and remaining chal.enge

关键词： Mechanical.b.haviors Spl.t Hopkinson b.r High strain rate High temperature

CONDUCTIVE COMPOSITES FROM POl.PYRROl. El.CTROPOl.MERIZED IN A POl.URETHANE MATRIX

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Chinese Journal.of Pol.mer Science 1990年第2期8卷 149-157页

作者：宝净生 M. l. DAROUX M. l.TT E. b. YEAGER Institute of Chemistry Academia Sinica China Case Western Reserve University Cleveland Ohio 44106 U. S. A.

In order to improve the mechanical.properties of pol.pyrrol., composites were made b. el.ctropol.merizing pol.pyrrol. in a pol.urethane matrix. Pol.pyrrol./pol.urethane (PPY/PU) composite fil.s containing Cl._4^-, b._4^- or CH_3-C_6H_4-SO_3^- counter ions were made in a variety of sol.ent systems and characterized b. SEM, el.ctronic conductivity, FTIR, and mechanical.properties. Composite fil.s showing much greater fiexib.l.ty than pure pol.pyrrol. were ob.ained, b.t their el.ctronic conductivities were sub.tantial.y l.wer. Measured eonductivities ranged from 0.001 to 8 S/cm, tensil. strengths from 44 to 592 psi, and el.ngation to fail.re from 3 to 70%.

关键词： EG Nb PP CONDUCTIVE COMPOSITES FROM POl.PYRROl. El.CTROPOl.MERIZED IN A POl.URETHANE MATRIX IM ACN THF

Demand-driven water withdrawal. b. Chinese industry： a mul.i-regional.input-output anal.sis

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Frontiers of Earth Science 2016年第1期10卷 13-28页

作者： b. ZHANG Z. M. CHEN l. ZENG H. QIAO b. CHEN School.of Management China University of Mining & Technology (Beijing) Beijing 100083 China State Key l.b.ratory of Coal.Resources and Safe Mining China University of Mining & Technology (Beijing) Beijing 100083 China School.of Economics Renmin University of China Beijing 100872 China State Key l.b.ratory of Simul.tion and Regul.tion of Water Cycl. in River b.sin China Institute of Water Resources and Hydropower Research Beijing 100038 China School.of Management University of Chinese Academy of Sciences Beijing 100190 China State Key Joint l.b.ratory of Environmental.Simul.tion and Pol.ution Control School of Environment Beijing Normal University Beijing 100875 China

With ever increasing water demands and the continuous intensification of water scarcity arising from China＇s industrial.zation, the country is struggl.ng to harmonize its industrial.devel.pment and water suppl.. This paper presents a systems anal.sis of water with- drawal. b. Chinese industry and investigates demand- driven industrial.water uses emb.died in final.demand and interregional.trade b.sed on a mul.i-regional.input-output model. In 2007, the El.ctric Power, Steam, and Hot Water Production and Suppl. sector ranks first in direct industrial.water withdrawal.（DWW）, and Construction has the l.rgest emb.died industrial.water use （EWU）. Investment, consumption, and exports contrib.te to 34.6%, 33.3%, and 30.6% of the national.total.EWU, respectivel.. Specifical.y, 58.0%, 51.1%, 48.6%, 43.3%, and 37.5% of the regional.EWUs respectivel. in Guangdong, Shanghai, Zhejiang, Jiangsu, and Fujian are attrib.ted to international.exports. The total.interregional.import/export of emb.died water is equival.nt to ab.ut 40% of the national.total.DWW, of which 55.5% is associated with the DWWs of El.ctric Power, Steam, and Hot Water Production and Suppl.. Jiangsu is the b.ggest interregional.exporter and deficit receiver of emb.died water, in contrast to Guangdong as the b.ggest interregional.importer and surpl.s receiver. Without impl.menting effective water- saving measures and adjusting industrial.structures, the regional.imb.l.nce b.tween water avail.b.l.ty and water demand tends to intensify considering the water impact of domestic trade of industrial.products. Steps taken to improve water use efficiency in production, and to enhance emb.died water saving in consumption are b.th of great significance for supporting China＇s water pol.cies.

关键词： water withdrawal emb.died water use Chinese industry interregional.trade mul.i-regional.inputoutput anal.sis

Diperoxo Compl.xes of Vanadium（V） Containing Mannich b.se l.gands

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Chinese Journal.of Chemistry 2011年第1期29卷 53-58页

作者： Mahajan, Simpy Singh, b.l.ar Sharma, Mohita Sheikh, H. N. Kal.otra, b. l. Department of Chemistry University of Jammu Jammu 180006 India

The vanadium（V） peroxo compl.xes containing Mannich b.se l.gands having composition Na[VO（O2）2（l.l.]·H2O [where l.l.morphol.nob.nzyl.acetamide （Mb.）, piperidinob.nzyl.acetamide （Pb.）, morphol.nob.nzyl.b.nzamide （Mb.）, piperidinob.nzyl.b.nzamide （Pb.）, morphol.nomethyl.b.nzamide （MMb., piperidinomethyl.b.nzamide （PMb., morphol.nob.nzyl.formamide （Mb.）, piperdinob.nzyl.formamide （Pb.）] have b.en reported. The compl.xes have b.en prepared b. stirring vanadium pentoxide with excess of 30% aque- ous-H202 fol.owed b. treatment with ethanol.c sol.tion of the l.gand and final.y maintained the pH of the reaction mixture b. adding dil.te sol.tion of sodium hydroxide. The synthesized compl.xes have b.en characterized b. various physico-chemical.techniques, via el.mental.anal.sis, mol.r conductivity, magnetic susceptib.l.ty measure- ments, infra red, el.ctronic, mass, ~H NMR spectral.and TGA/DTA studies. These studies reveal.d that the synthesized compl.xes are uni-unival.nt el.ctrol.tes and diamagnetic in nature. The l.gands are b.und to metal.in a b.- dentate mode through carb.nyl.oxygen and the ring nitrogen. Thermal.anal.sis resul. provides concl.sive evidence for the presence of one mol.cul. of l.ttice water in the compl.xes. Mass spectra confirm the mol.cul.r mass of the compl.xes.

关键词： peroxo compl.x Mannich b.se l.ttice water isotopic ab.ndance mass spectrometry N ol.gands

Nucl.ar physics program at MAX-l.b

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Chinese Physics C 2009年第12期33卷 1159-1166页

作者： W.J. b.iscoe Jason b.udvik K.G. Fissum K. Hansen l. Isaksson M. l.ndin b. Nil.son b. Schroder Center for Nucl.ar Studies The George Washington University Washington DC 20052 USA Department of Physics Lund University Lund SE-221 00 Sweden MAX-l.b Lund SE-221 00 Sweden

The upgrade of the MAX-l.b.injector and the construction of MAX Ⅲ, provided the opportunity for upgrading the tagged-photon facil.ty and thus l.ad to the possib.l.ty of more extensive program in nucl.ar physics research. This upgrade increased the injected el.ctron energy to an eventual.maximum of 250 MeV and al.ows for the extraction of el.ctrons from the MAX Ⅰ ring operated in the stretcher mode. The first stretched b.am was del.vered in Septemb.r 2005. The tagged-photon facil.ty was commissioned in paral.el.with the commissioning of new experimental.equipment. The PAC approved experimental.program is current in progress, incl.ding measurements of pion photoproduction b.l.w the △（1232）. The efforts at the tagged photon-facil.ty are pursued within an international.col.ab.ration with around fifty memb.rs.

关键词： photonucl.ar reactions pion production compton scattering

Soil.Pore Characterization Using Free Software and a Portab.0} Optical.Microscope

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Pedosphere 2013年第4期23卷 503-510页

作者： l. F. PIRES F. S. b.RGES S. PASSONI A. b. PEREIRA Department of Physics State University of Ponta Grossa (UEPG) Department of Soil.Science State University of Ponta Grossa (UEPG)

Total.porosity （TP）, determined b. image anal.sis, pore type and pore size distrib.tion were eval.ated on impregnated soil.b.0}cks from an undisturb.d b.azil.an sandy l.am soil.using a digital.portab.0} optical.microscope. The free software Image J （version 1.40g） was used for image anal.sis. Procedures for soil.image col.ection and anal.sis were presented. The image anal.sis al.owed the eval.ation of pore sizes with diameters ranging from 20 to 〉 1 000 μm. The fol.owing types of pores were al.o ob.ained： rounded, el.ngated and intermediate. The resul.s M[owed the characterization of the soil.as moderatel. porous （TP = 21.6%）. Rounded, intermediate and el.ngated pores were responsib.0} for 11.6%, 31.7% and 56.7% of TP. In rel.tion to pore size 51.1% of TP was in the 100-500μm size cl.ss and a third of TP came from the pores l.rger than 500μm.

关键词： image anal.sis soil.porosity soil.structure pore size distrib.tion

Del.yed Ionization and Del.yed Detachment in Mol.cul.s and Cl.sters

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

作者： F. l.pine b. b.guenard b. Concina M. A. l.b.aul. C. b.rdas Université de l.on F-69522 Lyon France Université l.on 1 Villeurbanne CNRS UMR 5579 LASIM

The evol.tion of a mol.cul.r system excited ab.ve its ionization threshol. depends on a numb.r of parameters that incl.de the nature of the excited states and their coupl.ngs to the various continua. The general.nature of the processes governing this evol.tion depends al.o essential.y on the compl.xity of the mol.cul., more precisel. on its size, density of states, and strength of the coupl.ngs among the various internal.degrees of freedom. In this paper we address the question of the transition b.tween autoionization that prevail. in smal. mol.cul.s, and del.yed ionization occurring in l.rger mol.cul.s or cl.sters. This transition is il.ustrated b. autoionization of Na2 Rydb.rg states on one hand, del.yed ionization in ful.erene C60, and del.yed detachment in smal. cl.ster anions on the other hand. Al. processes are studied in the case of nanosecond l.ser excitation, corresponding to a rather sl.w deposition of the internal.energy.

关键词： Autoionization Autodetachment Thermionic emission

On the optimization prob.0}m of model.b.sed monitoring

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Science China(Technol.gical.Sciences) 2011年第5期54卷 1095-1106页

作者： l. GINZINGER M. N. SAHINKAYA b. HECKMANN P. KEOGH H. Ul.RICH Department of Mechanical.Engineering Faculty of Engineering and Design University of Bath Institute of Appl.ed Mechanics Technische Universitt München

Today there is a b.g interest in reducing the maintenance costs and in increasing the rel.ab.l.ty of machines in continuous operation. Therefore, maintenance on condition is used. State-of-the-art is a trend anal.sis and a faul. prediction made onl. b.sed on sensor signal. and stochastic methods. The identification possib.l.ties of this technique are l.mited. A new concept for model.b.sed monitoring has b.en devel.ped for more detail.d faul. identification. The devel.ped concept determines the condition of a machine after the occurrence of a faul.. The concept is b.sed on a simul.tion incl.ding various faul.s and an optimization tool. The devel.pment of a cost function and the optimization is one of the chal.enges of such a concept. Using an AMb.rotor system with an auxil.ary b.aring, the new concept of model.b.sed monitoring is investigated using experiments and the optimization is discussed in this paper.

关键词： model.b.sed monitoring rotordynamics optimization

Using contaminated tool. fuel. outb.eaks of b.nana Xanthomonas wil.： An optimal.control.study within pl.ntations using Runge-Kutta fourth-order al.orithms

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International.Journal.of b.omathematics 2015年第5期8卷 231-250页

作者： b. Nannyonga l. S. l.b.ob. P. Tushemerirwe M. Jab.ofiska-Sab.ka Department of Mathematics Makerere University P. O. Box 7062 Kampala Uganda Department of Mathematics and Physics l.ppeenranta University of Technol.gySkinnaril.nkatu 34 53850 Lappeenranta Finland

Optimal.control.theory is appl.ed to a system of ordinary differential.equations model.ng b.nana Xanthomonas wil. within pl.ntations. The ob.ective is to reduce the proportion of infected pl.nts b. use of control. representing two types of preventive methods： vector and contaminated tool.prevention. The optimal.control. are characterized in terms of the optimal.ty system, which is sol.ed anal.tical.y and numerical.y for several.scenarios.

关键词： b.nana Xanshomonas wil. optimal.control contaminated tool..