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Differential Representations of SO(4) Dynamical Group

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Communications in Theoretical Physics 2008年第7期50卷 63-68页

作者： ZHAO Dun wang shun-Jin LUO Hong-Gang School of Mathematics and Statistics Lanzhou University Lanzhou 730000 China Department of Physics Sichuan University Chengdu 610064 China Center of Theoretical Physics and Interdisciplinary Studies Lanzhou University Lanzhou 730000 China Institute of Theoretical Physics Academia Sinica Beijing 100080 China

In this paper we present systematic differential representations for the dynamical group SO(4).Theserepresentations include the left and the right differential representations and the left and the right adjoint differentialrepresentations in both the group parameter space and its coset *** are the generalization of the differentialrepresentations of the SO(3) rotation group in the Euler *** representations may find their applications in thestudy of the physical systems with SO(4) dynamical symmetry.

关键词： dynamical group differential representation group action coset space

Primary studies on integration optimization of differential steering of electric vehicle with motorized wheels based on quality engineering

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Science China(Technological Sciences) 2011年第11期54卷 3047-3053页

作者： ZHAO WanZhong wang ChunYan SUN PeiKun LIU shun Department of Automotive Engineering Nanjing University of Aeronautics andAstronautics Nanjing 210016 China State Key Laboratory of Automotive Safety and Energy Tsinghua University Beijing 100086 China

The model of the differential steering system(DSS) of electric vehicle with motorized wheels and the three-degree-of-freedom dynamic model of vehicle are *** on these models,the concepts and quantitative expressions of steering road feel,steering portability and steering stability are *** integrating the Monte Carlo descriptive sampling,elitist non-dominated sorting genetic algorithm(NSGA-II) and Taguchi robust design method,the system parameters are optimized with steering road feel and steering portability as optimization targets,and steering stability and steering portability as *** simulation results show that the system optimized based on quality engineering can improve the steering road feel,guarantee steering stability and steering portability and thus provide a theoretical basis for the design and optimization of the electric vehicle with motorized wheels system.

关键词： vehicle engineering electric vehicle with motorized wheels differential assisted steering quality engineering integration optimization

La_2Zr_2O_7 TBCs toughened by Pt particles prepared by cathode plasma electrolytic deposition

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International Journal of Minerals,Metallurgy and Materials 2016年第6期23卷 704-715页

作者： shun-jie Deng Peng wang Ye-dong He Jin Zhang Institute for Advanced Materials and Technology University of Science and Technology Beijing

La2Zr2O7 thermal barrier coatings（TBCs） with dispersed Pt particles were prepared by cathode plasma electrolytic deposition（CPED） with ceramic balls added to the cathode region. Compared with the conventional CPED, when ceramic balls are used in the cathode region, the plasma discharge ignition current density decreases approximately 62-fold and the stable plasma discharges occur at the whole cathode surface. Such TBCs with a thickness of 100 μm exhibit a crack-free surface and are composed of pyrochlore-structured La2Zr2O7. Cyclic oxidation, scratching, and thermal insulation capability tests show that such TBCs not only exhibit high resistance to oxidation and spallation but also provide good thermal insulation. These beneficial effects are attributed to the excellent properties of TBCs, such as good thermal insulation because of low thermal conductivity, high-temperature oxidation resistance because of low-oxygen diffusion rate, and good mechanical properties because of the toughening effect of Pt particles.

关键词： thermal barrier coatings platinum oxidation resistance toughening electrolytic deposition

Numerical Simulation of Rogue Waves by the Local Discontinuous Galerkin Method

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Chinese Physics Letters 2014年第4期31卷 1-4页

作者： CAI Wen-Jun wang Yu-shun SONG Yong-Zhong Jiangsu Provincial Key Laboratory for NSLSCS School of Mathematics and Sciences Nanjing Normal University Nanjing 210023

We study rogue waves described by nonlinear Schr6dinger equations. Such wave solutions are so different from conventional soliton solutions that classic methods such as the Crank-Nicolson scheme cannot work for these cases. Fortunately, we find that the local discontinuous Galerkin method equipped with Dirichlet boundary conditions can simulate rogue waves very well. Several numerical examples are presented to show such interesting wave solutions.

关键词： Method Numerical Crank–Nicolson

Fermi Blazars in the Zwicky Transient Facility Survey:Properties of Large Optical Variations

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Research in Astronomy and Astrophysics 2024年第10期24卷 104-115页

作者： Si-Si Sun Zhong-Xiang wang shun-Hao Ji Department of Astronomy School of Physics and AstronomyYunnan UniversityKunming 650091China Shanghai Astronomical Observatory Chinese Academy of SciencesShanghai 200030China

We analyze the optical light curve data,obtained with the Zwicky Transient Facility(ZTF)survey,for 47 γ-ray blazars monitored by the Large Area Telescope onboard the Fermi Gamma-ray Space Telescope(Fermi).These 47sources are selected because they are among the Fermi blazars with the largest optical variations in the ZTF *** color-magnitude variation patterns are seen in them,with one being redder-to-stable-when-brighter(RSWB;in 31 sources)and the other being stable when brighter(in 16 sources).The patterns fit with the results recently reported in several similar studies with different ***,we find that the colors in the stable state of the sources share similar values,for which(after being corrected for the Galactic extinction)most sources are in a range of 0.4–*** feature could be intrinsic and may be applied in,for example,study of the intragalactic *** also determine the turning points for the sources showing the RSWB pattern,after which the color changes saturate and become *** find a correlation between optical fluxes and γ-ray fluxes at the turning *** physical implications of the correlation remain to be investigated,probably better with a sample of high-qualityγ-ray flux measurements.

关键词： (galaxies:)BL Lacertae objects:general (galaxies:)quasars:general gamma-rays:galaxies

Theoretical Design of High-spin Organic Molecules with —~* N—S— as a Spin-containing Fragment and Heterocycle as End Groups

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Chemical Research in Chinese Universities 2006年第5期22卷 631-634页

作者： wang Li-min CHU De-qing ZHANG Jing-ping wang Rong-shun Faculty of Material and Chemical Engineering Tianfin Polytechnic University Tianjin 300160 P. R. China Faculty of Chemistry Northeast Normal University Changchun 130024 P. R. China

Novel stable high-spin molecules possessing three different arranging fashions were designed with —^＊N—S— as a spin-containing （SC） fragment, an aromatic group, such as benzene （ 1 ）, pyridine （2）, pyridazine （3） , pyrimidine （4）, pyrazine （5） or triazine （6） as end groups （EG）, and phenyl as a ferromagnetic coupling （FC） unit. The effects of different EG on the spin multiplicities of the ground states and their stabilities were investigated by means of the AM1-CI approach. All the investigated molecules corresponded to the FC and possessed high-spin ground states. The spin on the two atoms of the SC fragment was not in agreement with the delocalization results in the specific stability of —^＊N—S—. In those molecules, the stabilities of the triplet states decreased when the distance between the atoms of central SC fragments （—N—） increased. The stabilities of the triplet states of compounds 1a-n, 1b-n and 1c-n, with heterocycles as EG were higher than those of the triplet states of those compounds with phenyl as EG. Furthermore, the stahilities of the triplet states of the compounds with pyrimidine and triazine as EG were higher than those with pyridine, pyridazine or pyrasine as EG.

关键词： Heterocycle End group Biradical High-spin AM1-CI

Porous a-Al_2O_3 thermal barrier coatings with dispersed Pt particles prepared by cathode plasma electrolytic deposition

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International Journal of Minerals,Metallurgy and Materials 2016年第1期23卷 92-101页

作者： Peng wang Ye-dong He shun-jie Deng Jin Zhang Beijing Key Laboratory for Corrosion Erosion and Surface Technology University of Science and Technology Beijing

Porous α-Al2O3 thermal barrier coatings （TBCs） containing dispersed Pt particles were prepared by cathode plasma electrolytic deposition （CPED）. The influence of the Pt particles on the microstructure of the coatings and the CPED process were studied. The prepared coatings were mainly composed of α-Al2O3. The average thickness of the coatings was approximately 100 μm. Such single-layer TBCs ex- hibited not only excellent high-temperature cyclic oxidation and spallation resistance, but also good thermal insulation properties. Porous α-Al2O3 TBCs inhibit further oxidation of alloy substrates because of their extremely low oxygen diffusion rate, provide good thermal insu- lation because of their porous structure, and exhibit excellent mechanical properties because of the toughening effect of the Pt particles and because of stress relaxation induced by deformation of the porous structure.

关键词： porous material thermal barrier coatings alumina platinum electrolytic deposition oxidation

Environmental and tectonic significance of Late Permian reefs in the Linxi and adjacent areas in Inner Mongolia of China

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Science China Earth Sciences 2016年第7期59卷 1463-1476页

作者： TIAN Shu Gang ZHANG Yong Sheng GONG Yue Xuan LI Zi shun GAO Lian da ZHAI da Xing ZHU Chang Wei Institute of Geology Chinese Academy of Geological Sciences Institute of Mineral Resources Chinese Academy of Geological Sciences Department of Science and Technology Chinese Academy of Geological Sciences

Many plateau-edge reefs and reef mounds of the Late Permian have been discovered in Linxi County and adjacent areas of Inner Mongolia, China. These reefs verify that the Hinggan-Inner Mongolia Area was an open and unobstructed sea-trough in Late Permian. Facies and sequences of reef strata in Member 4 and Member 5 of the Linxi Formation were studied for information to reconstruct the closing process of the Linxi-Jiutai chasm in the sea-trough, i.e., to constrain subsidence, uplift, and final closing. Ages of the reef-bearing strata have been determined to be late and end of Late Permian, based on ranges or abundances of diverse fossils. Six reef-building organic assemblages were distinguished, representing different ecologic conditions, according to morphological functions and paleoecological adaptations of organisms including primarily sponges, bryozoans, and calcareous algae. Two types of shelf slopes, the gentle slope and the steep slope, have been interpreted for Member 4 and Member 5 of the Linxi Formation, based on the assemblages. The locations of outcrops, and types of these reefs delineate the north margin of Sino-Korea Platform, and define uplift and final closing of the Linxi-Jiutai chasm at the end of Late Permian.

关键词： Reefs Facies sequence Paleoecology Late Permian Inner Mongolia

Dynamical Properties of Two Coupled Dissipative QED Cavities Driven by Coherent Fields

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Communications in Theoretical Physics 2007年第2X期48卷 232-242页

作者： HOU Bang-Pin wang shun-Jin wang Gang SUN Wei-Li School of Physics and Electronic Engineering Sichuan Normal University Chengdu 610066 China Department of Physics Sichuan University Chengdu 610065 China College of Computer and Communication Engineering Southwest Jiaotong University Chengdu 610031 China

When two identical QED cavities driven by the coherent fields are located in a uniform environment, in addition to dissipation, there appears an indirect coupling between the two cavities induced by the background fields. We investigate the effects of the coherent fields, the dissipation as well as the incoherent coupling on the following dynamical properties of the system： photon transfer, reversible decoherence, and quantum state transfer, etc. We find that the photons in the cavities do not leak completely into the environment due to the collective coupling between the cavities and the enviroment, and the photons are transferred irreversibly from the cavity with more photons to the cavity with less ones due to the incoherent coupling so that they are equally distributed among the two cavities. The coherent field pumping on the two cavities increases the mean photons, complements the revived magnitude of the reversible decoherence, but hinders the quantum state transfer between the two cavities. The above phenomena may find applications in quantum communication and other basic fields.

关键词： photon transfer reversible decoherence quantum state transfer algebraic dynamical method two coupled dissipative QED cavities driven by coherent fields