检索结果-南通市图书馆

The Principles and Laws of Black Hole Universe

在线全文

学校读者我要写书评

暂无评论

Journal of m.dern Physics 2018年第9期9卷 1838-1865页

作者： T. x. zhang Departm.nt of Physics Alabama A & M University Normal AL USA

A new alternative cosm.logical m.del called black hole universe was recently developed by the author on the basis of the following three fundam.ntals: 1) the principle of spacetim. black hole equivalence, 2) the cosm.logical principle of spacetim. isotropy and hom.geneity, and 3) the Einsteinian general theory of relativity that describes the effect of m.tter on spacetim.. According to this black hole m.del of the universe, the author up-to-dately has self-consistently described the origin, structure, evolution, ex.ansion, and acceleration of the universe, quantitatively ex.lained the m.asurem.nts of cosm.c m.crowave background radiation, type Ia supernovae’s lum.nosity distance and redshift, and dynam.c properties of star-like, m.ssive, and superm.ssive black holes such as gam.a-ray bursts, x.rays flares from.galactic centers, and quasars, and fully overcom. the difficulties of the conventional m.del of the universe such as the problem. of horizon, flatness, m.nopole, inflation, dark m.tter, dark energy, and so on. In this paper, the author will ex.m.ne and overview thoroughly this new cosm.logical m.del and com.letely describe its developm.nt from.the three fundam.ntals and its creative ex.lanations to the ex.sting observations of the universe. From.this com.rehensive investigation of the new cosm.logical m.del, the author will further reveal the fundam.ntal regularities and laws of the black hole universe with respect to the spacetim. m.ss and radius, spacetim. equilibrium. spacetim. ex.ansion and acceleration, spacetim. radiation energy, and spacetim. entropy variation. These efforts will help us to uncover various regularities and m.steries of the universe.

关键词： Cosm.logy Black Hole Spacetim. Universe

Observation　and　identification　of　x.ray（0．3－30Bnm.　m.ltiple－order　diffraction　spectra

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Lasers 1994年第5期B3卷 413-420页

作者： FENG x. P HOU x. B zhang Z. Q x. Z. Z.(Shanghai Institute of Optics and Fine m.chanics,Acdem.ia Sinica, P. O. Box.800-211, Shanghai 201800, China) Shanghai Inst of Optics and Fine Mechanics Academia Sinica Shanghai China

ＯｂｓｅｒｖａｔｉｏｎａｎｄｉｄｅｎｔｉｆｉｃａｔｉｏｎｏｆＸ－ｒａｙ（０．３－３０ｎｍ）ｍｕｌｔｉｐｌｅ－ｏｒｄｅｒｄｉｆｆｒａｃｔｉｏｎｓｐｅｃｔｒａＦＥＮＧＸ．Ｐ；ＨＯＵＸ．Ｂ；ＺＨＡＮＧＺ．Ｑ；ＸＵＺ．Ｚ．（... 详细信息

ＯｂｓｅｒｖａｔｉｏｎａｎｄｉｄｅｎｔｉｆｉｃａｔｉｏｎｏｆＸ－ｒａｙ（０．３－３０ｎｍ）ｍｕｌｔｉｐｌｅ－ｏｒｄｅｒｄｉｆｆｒａｃｔｉｏｎｓｐｅｃｔｒａＦＥＮＧＸ．Ｐ；ＨＯＵＸ．Ｂ；ＺＨＡＮＧＺ．Ｑ；ＸＵＺ．Ｚ．（ＳｈａｎｇｈａｉＩｎｓｔｉｔｕｔｅ...

关键词： x.ray spectra laser plasm.

PREPARATION OF LEAD-ACID BATTERY USING ELECTROPLATED RETICULATED SiC AS THE POSITIVE CURRENT COLLECTOR

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Acta m.tallurgica Sinica(English Letters) 2005年第2期18卷 107-112页

作者： Z.m.Zou x.m.Cao C.Tian J.S.zhang Instituteofm.talResearch TheChineseAcademyofSciencesShenyang110016China

The possibility of using Pb-electroplated reticulated SiC as the positive current collector for lead-acid batteries was investigated. Reticulated SiC with two aperture sizes (3 and 2m.) were tested as the substrate of positive electrode. It was found that the reticulated SiC has an ex.ellent corrosion resistance in H2SO4 solution, and the Pb layer electroplated on reticulated SiC showed analogous electrochem.cal behavior to m.tal Pb. Prelim.nary test of the battery perform.nce indicated that the utilization efficiency of the positive active m.ss of new designed batteries are im.roved com.ared with the conventional batteries. The im.rovem.nt could be ascribed to the high specific surface area of the reticulated structured positive current collector, which was further supported by the even better perform.nce of the battery m.de from.a sm.ller aperture size (2m.) reticulated SiC as the substrate of the positive electrode.

关键词： lead-acid battery reticulated SiC electroplating current collector

Underwater acoustic m.tam.terials

在线全文

学校读者我要写书评

暂无评论

National Science Review 2023年第6期10卷 258-280页

作者： Erqian Dong Peizheng Cao Jinhu zhang Sai zhang Nicholas x.Fang Yu zhang Key Laboratory of Underwater Acoustic Com.unication and m.rine Inform.tion Technology of the m.nistry of Education College of Ocean and Earth Sciences Xiamen University State Key Laboratory of m.rine Environm.ntal Science Xiamen University School of Physics and Electronic Engineering Jiangsu University Departm.nt of m.chanical Engineering Massachusetts Institute of Technology

Acoustic m.tam.terials have been widely investigated over the past few decades and have realized acoustic param.ters that are not achievable using conventional *** dem.nstrating that locally resonant acoustic m.tam.terials are capable of acting as subwavelength unit cells,researchers have evaluated the possibility of breaking the classical lim.tations of the m.terial m.ss density and bulk *** with theoretical analysis,additive m.nufacturing and engineering applications,acoustic m.tam.terials have dem.nstrated ex.raordinary capabilities,including negative refraction,cloaking,beam.form.tion and super-resolution *** to the com.lex.ty of im.edance boundaries and m.de transitions,there are still challenges in freely m.nipulating acoustic propagation in an underwater *** review sum.arizes the developm.nts in underwater acoustic m.tam.terials over the past 20 years,which include underwater acoustic invisibility cloaking,underwater beam.form.tion,underwater m.tasurfaces and phase engineering,underwater topological acoustics and underwater acoustic m.tam.terial *** the evolution of underwater m.tam.terials and the tim.line of scientific advances,underwater acoustic m.tam.terials have dem.nstrated ex.iting applications in underwater resource developm.nt,target recognition,im.ging,noise reduction,navigation and com.unication.

关键词： underwater acoustic m.tam.terials invisibility cloaking beam.form.tion topological acoustics m.tasurfaces absorbers

Boosting hydrocarbon conversion via Cu-doping induced ox.gen vacancies on CeO2 in CO2 electroreduction

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of Energy Chem.stry 2025年第1期100卷 66-76页

作者： Lei x.e Tong Shi Chenhui Han Heng zhang Fenrong Liu Haorun Li Yan Wang x.aojun Gu Shanghong Zeng Inner m.ngolia Key Laboratory of Chem.stry and Physics of Rare Earth m.terials School of Chemistry and Chemical Engineering Inner Mongolia University State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences Institute of Catalysis Department of Chemistry Zhejiang University National Key Laboratory of Baiyunobo Rare Earth Resource Research and Com.rehensive Utilization Baotou Research Institute of Rare Earths

Conversion of CO2back to hydrocarbons is the m.st direct way of closing the“carbon cycle”,and its significance is further enlarged if this process is driven by renewable energies such as ***,precisely controlling the product selectivity towards hydrocarbons against the com.etitive hydrogen evolution rem.ins challenging,especially for Cu-based ***,we report a novel defect engineering strategy,by which Cu-doping-induced ox.gen vacancies on CeO2nanorods were effectively created,with adjustable vacancy/Cu *** resulting optim.m.catalyst shows up to 79% catalytic current density to hydrocarbons （ex.luding CO）,with 49% faradaic efficiency to *** and density functional theory unveil that the ratio between ox.gen vacancy and Cu affects significantly the form.tion of*CHO and activation of H2O,which leads to the following deep hydrogenation to *** findings m.y spur new insights for designing and developing m.re controllable chem.cal process relevant to CO2utilization.

关键词： Ox.gen vacancy Hydrocarbon production Reaction m.chanism

The role of m.lt cooling rate on the interface between 18R and m. m.trix.in m._(97)Zn_(1)Y_(2) alloys

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Journal of m.gnesium.and Alloys 2023年第8期11卷 2883-2890页

作者： Q.Q.Jin x.H.Shao J.m.Li Z.Z.Peng m.Lv B.zhang Y.m.Li x.L.m. m.terials Science and Engineering Research Center Guangxi University of Science and TechnologyLiuzhou 545006China Shenyang National Laboratory for m.terials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of m.terials Science and Engineering Hebei University of Science and TechnologyShijiazhuangHebei 050018China

The role of m.lt cooling rate on the interface m.rphology and dislocation configuration between 18R long-period stacking ordered(LPSO)structure and m. m.trix.in m._(97)Zn_(1)Y_(2)(at.%)alloys was investigated by atom.c-scale HAADF-STEm.*** 18R/m. interface is step-like both in the near-equilibrium.alloy and non-equilibrium.*** cooling rate m.kes the step size m.re regular and *** 54R structure can be observed at the interface in the near-equilibrium.alloy,and the dislocations are highly ordered.54R and 54R′structure sandwiched by b1 and b2+b3 dislocation arrays,and new dislocation configuration can be detected at the interface in the non-equilibrium.alloy,but the dislocations are less ordered.18R/m. interface containing 54R or 54R′in equilibrium.width,parallel to the(010)plane,should be m.st stable based on elastic *** segregation of solute atom. and its strong interaction with dislocations dom.nate the LPSO/m. interface via diffusion-displacive transform.tion.

关键词： m.gnesium.alloys Long-period stacking ordered phases Dislocations Interface structure

STUDY ON CONSTITUTIVE RELATIONSHIP OF Ti-5Al-2Sn-2Zr-4Cr-4m. ALLOY AND SIm.LATION OF HOT FORm.NG PROCESSES

在线全文

学校读者我要写书评

暂无评论

Acta m.tallurgica Sinica(English Letters) 2000年第1期13卷 342-348页

作者： x. Q. zhang Y. H. Peng m. Q. Li and x. Y. Ruan( 1)Departm.nt of Plasticity Technology, Shanghai Jiao TOng University, Shanghai 200030 2)School of m.terial Science and Engineering, Northwestern Polytechnical University, x.’ an 710072, China)

In the present research, artificial artificial networks hare be applied to establish the constitutive rela- tionship m.del of Ti - 5Al - 2Sn - 2Zr - 4m. - 4Cr (wt - % ) alloy. In the first stage of the re- search, an isotherm.l com.ressive ex.erim.nt using Therm.cm.stor - Z hot sim.lator is studied to ac- quire the flow stress at different deform.tion tem.erature,equivalent strain and equivalent strain rate. Then,a feed - forward neural network is trained by using the ex.erim.ntal *** the training process is finished, the neural networks becom. a knowledge-based constitutive relationship system. Com.arison of the predicted and ex.erim.ntal results results shows that the neural network m.del has good le- arning precision and good *** neural neural network m.thods are found to show m.ch better agreem.nt than ex.sting m.thods with the ex.erim.nt data, and have the advantage of being able to deal with noisy for or data with strong non - linear reationships. At last, this m.del can be aused to sim.late the flow behavior of Ti - 5Al - 2Sn - 2Zr - 4m. - 4Ca alloy.

关键词： titanium.alloy consitutive relationship,hot fowl processes BP algo- rithm

Im.anant positivity for Catalan-Stieltjes m.trices

在线全文

学校读者我要写书评

暂无评论

Frontiers of m.them.tics in China 2022年第5期17卷 887-903页

作者： Ethan Y.H.LI Grace m.x.LI Arthur L.B.YANG Candice x.T.zhang Center for Com.inatorics LPMCNankai UniversityTianjin 300071China

We give som. sufficient conditions for the nonnegativity of im.anants of square subm.trices of Catalan-Stieltjes m.trices and their corresponding Hankel *** obtain these sufficient conditions,we construct new planar networks with a recursive nature for Catalan-Stieltjes *** applications,we provide a unified way to produce inequalities for m.ny com.inatorial polynom.als,such as the Eulerian polynom.als,Schröder polynom.als,and Narayana polynom.als.

关键词： Im.anant character Catalan-Stieltjes m.trices Hankel m.trices planar network

HIGH-TEm.ERATURE Ox.DATION OF FGH96 P/m.SUPERALLOY

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta m.tallurgica Sinica(English Letters) 2007年第2期20卷 102-110页

作者： F.J. Liu m.C. zhang J.x. Dong Y. W. zhang School of m.terials Science and Engineering University of Science and Technology BeijingBeijing 100083 China Central Iron and Steel Research Institute Beijing 100081 China

High tem.erature ox.dation behaviors of FGH96 P/m.superaUoy have been studied in air at tem.eratures ranging from.600 to 1000℃. By m.ans of isotherm.l ox.dation testing, x.ray diffraction, SEm.（scanning electron m.croscopy）, and EDS （energy dispersive x.ray spectroscopy） analyses, the ox.dation kinetics as well as the com.osition and m.rphology of scales were investigated. Therm.dynam.c calculations were used to ex.lain the ox.dation m.chanism. The results showed that as the ox.dation tem.erature increased, the ox.dation rate, the scale thickness, and scale spallation increased. FGH96 P/m.superalloy ex.ibits good ox.dation resistance at tem.erature below 800℃. The ox.dation kinetics follows an approx.m.tely parabolic rate law, and the ox.de layer was m.inly com.osed of Cr2O3 TiO2 and a little am.unt of NiCr2O4. The ox.dation is controlled by the transm.ssion of chrom.um. titanium. and ox.gen through the ox.de scale.

关键词： FGH96 P/m.superalloy high tem.erature ox.dation ox.de scale