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A new orthogonality relationship for orthotropic thin plate theory and its variational principle

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Science china(physics,Mechanics & Astronomy) 2005年第3期48卷 371-380页

作者： LUO Jianhui 1 , LONG Yuqiu 2.& LIU Guangdong 1 1. College of Civil Engineering, Hunan university, Changsha 410082. china 2. Department of Civil Engineering, Tsinghua university, Beijing 100084, china 1. College of Civil Engineering Hunan University 410082 Changsha China 2. Department of Civil Engineering Tsinghua University 100084 Beijing China

The thought how dual vectors are constructed in a new orthogonality relationship for theory of elasticity is generalized into orthotropic thin plate bending problems by using the analogy theory between plane elasticity problems and plate bending problems. Dual differential equations are directly obtained by using a mixed variables method. A dual differential matrix to be derived possesses a peculiarity of which principal diagonal sub-matrixes are zero matrixes. Two independently and symmetrically orthogonality sub-relationships are discovered. By using the integral form for elastic bending theory of orthotropic thin plate the orthogonality relationship is demonstrated. By selecting felicitous dual vectors a new orthogonality relationship for theory of elasticity can be generalized into elastic bending theory of orthotropic thin plate. By using the integral form a variational principle which is relative to differential form and a whole function expression are proposed.

关键词： theory of elasticity, thin plate theory, dual vectors, orthogonality relationship, orthotropic, variational principle.

Effects of annealing on structural, optical and electrical properties of Al-doped ZnO thin films

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Science china(physics,Mechanics & Astronomy) 2004年第5期47卷 588-596页

作者： CHEN Yanwei1,2. YU Wenhua1 & LIU Yichun1,2.1. Centre for Advanced Optoelectronic Functional Material Research, Northeast Normal university, Changchun 13002., china 2. Key {2. of Excited State Processes, Changchun Institute of Optics, Fine Mechanics and physics, Chinese Academy of Sciences, Changchun 13002., china 1. Centre for Advanced Optoelectronic Functional Material Research Northeast Normal University 130024 Changchun China 2. Key laboratory of Excited State Processes Changchun Institute of Optics Fine Mechanics and Physics Chinese Academy of Sciences 130021 Changchun China

In this paper, the structural, electrical and optical properties of Al-doped zinc oxide (ZnO: Al) thin films onto quartz substrates prepared by electron beam evaporation technique were studied. All samples are polycrystal with a hexagonal structure andc-axis preferred orientation. The intense UV emissions and weak deep-level green emissions were observed. The films show high transparency, conductivity and high carrier concentration. Van der Pauw measurements show that the films are n-type degenerate semiconductor. The lowest resistivity is 6.7×10?4 Ω⊙cm at room temperature. These films exhibit a carrier density above 102. cm?3. The conduction mechanism was discussed. The behavior of metallic conduction can be observed in the high temperature range.

关键词： ZnO: Al thin film, photoluminescence, electrical properties, structural properties, Van der Pauw measurement.

A pulse radiolysis study on electron affinity of piperonal

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Science china Chemistry 2005年第5期48卷 476-480页

作者： MA Jianhua1, LIN Weizhen2. WANG Wenfeng2.& YAO Side2.1. College of Biology Engineering, Jimei university, Xiamen 36102., china 2. Shanghai Institute of Applied {2., Chinese Academy of Sciences, Shanghai 2.1800, china 1. College of Biology Engineering Jimei University 361021 Xiamen China 2. Shanghai Institute of Applied physics Chinese Academy of Sciences 201800 Shanghai China

The piperonal electron affinity was studied using pulse radiolysis technique. The electron transfer reaction process between piperonal and anthraquinone-2.sulfate was observed in the pH 7 phosphoric acid salt buffer. The transient absorption spectra of electron transfer re-action between piperonal and anthraquinone-2.sulfate were obtained, and the initial proof of the electron transfer between electron donor and acceptor was provided directly. The one-electron reduction potential of piperonal was determined to be ?0.457 V.

关键词： piperonal, pulse radiolysis, one-electron reduction potential.

Doubly contracted CI method and applications

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Science china Chemistry 2004年第4期47卷 276-282页

作者： WANG Yubin1, HAN Huixian1, ZHAI Gaohong2.,SUO Bin1 & WEN Zheny1,2.1. Institute of Modern physics, Northwest university, Xian 710069,{2. 2. laboratory of Physico-Inorganic Chemistry, Department of Chemistry, Northwest university, Xian 710069,china Correspondence should be addressed to Wen Zhenyi 1. Institute of Modern physics Northwest University 710069 Xian China 2. laboratory of Physico-Inorganic Chemistry Department of Chemistry Northwest University 710069 Xi’an China

Based on the hole-particle correspondence an approximate so-called doubly contracted CI scheme is proposed. Examples calculated based on the doubly contracted CI (DCCI) scheme show that the number of configurations after contraction is reduced by three orders of magnitude, and the computation time is reduced by an order of magnitude. The examples also show that compared with experiments the DCCI and uncontracted CI have similar and reasonable accuracy to some spectroscopic parameters.

关键词： doubly contracted CI hole-particle symmetry approximate MRCI

Research on nonlinear constitutive relationship of permanent deformation in asphalt pavements

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Science china(physics,Mechanics & Astronomy) 2006年第6期49卷 671-682页

作者： PENG Miaojuan1 & XU Zhihong2.1. Department of Civil Engineering,Shanghai university,Shanghai 2.0072.china 2. School of Transportation Engineering,Tongji university,Shanghai 2.0092.china 1. Department of Civil Engineering Shanghai University Shanghai 200072 China 2. School of Transportation Engineering Tongji University Shanghai 200092 China

To predict correctly the rut depths in asphalt pavements,a new nonlinear viscoelastic-elastoplastic constitutive model of permanent deformation in asphalt pave-ments is presented. The model combines a generalized Maxwell model with an elasto-plastic one. Then from the creep theory,the linear and nonlinear constitutive equations of the generalized Maxwell model are obtained. From the nonlinear finite element method for the rutting of the asphalt pavement,the rut depths of 4 asphalt-aggregate mixtures are obtained. And the results are compared with the ones from the finite element method by SHRP and the experiments by SWK/UN. The results in this paper are better than the ones by SHRP,and agree with the ones of the experiment by SWK/UN. This shows that the nonlinear viscoelastic-elastoplastic constitutive model,which is presented in this paper for the rutting of the asphalt pavement,is effective. The properties,such as nonlinear elastic-ity,plasticity,viscoelasticity and nonlinear viscoelasticity,which affect the rutting of an asphalt pavement,can be shown in the model. And the characteristics of the permanent deformation of the asphalt pavement can be presented entirely in the model.

关键词： asphalt pavement,permanent deformation,nonlinear viscoelastic-elastoplastic constitutive relationship,generalized Maxwell model,creep compliance.

Solvothermal synthesis of nanocrystalline FeS_2

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Science china(physics,Mechanics & Astronomy) 2005年第2期48卷 188-200页

作者： CHEN Yanhua1, ZHENG Yufeng1, ZHANG Xiaogang2. SUN Yanfei1 & DONG Youzhong11. physics Department of Xinjiang university, Urumqi 830046,{2. 2. Institute of Applied Chemistry of Xinjiang university, Urumqi 830046,{2. physics Department of Xinjiang university Urumqi 830046 China Institute of Applied Chemistry of Xinjiang university Urumqi 830046 China

This paper reports on the synthesis of the nanocrystalline FeS2.via a solvent-thermal process. Using FeSO4 and NH2.SNH2.as precursors and polyvinyl- pyrrolidone (PVP) as a protective agent (dispersant), we have successfully synthesized nanocrystalline FeS2.both under acidic conditions (pH = 5) and under alkali conditions (pH = 10) at various temperatures and for different time in alcohol-water solution. X-ray diffraction (XRD), Transmission electron microscopy (TEM) and Ultraviolet Visible (UV-VIS) spectroscopy were used to characterize the morphology, structure, particle size and optical characterization of sample synthesized under acidic condition, and the XRD pattern was refined by Rietveld method. The experimental result shows that nanocrystalline FeS2.with uniform size, highly crystallized quality and excellent dispersivity has been synthesized at 2.0℃for 36 h.

关键词： FeS2 (Pyrite), solvothermal, PVP, the Rietveld method.

The tri-band high spectral resolution spectrometer with gratings in tandem for the charge-exchange recombination spectroscopy diagnostic system on HL-2. tokamak

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Plasma Science and Technology 2024年第6期26卷 103-110页

作者：刘亮余德良马倩何小斐 Maarten DE BOCK Manfred von HELLERMANN Michael WALSH 陈文锦何小雪魏彦玲张能李栋魏会领 the HL-2. Team Southwestern Institute of physics Chengdu 610041People’s Republic of China College of physics and Optoelectronic Technology Baoji University of Arts and SciencesBaoji 721000People’s Republic of China ITER Organization Route de Vinon-sur-VerdonCS 90046St.Paul Lez Durance Cedex 13067France Fusion Spectroscopy Markgraf-Albrecht Str.14Berlin 10711Germany

Charge-exchange(CX) recombination spectroscopy is a powerful tool monitoring ion temperature and plasma rotation with good temporal and spatial resolutions. A compact, new design for a high-throughput, tri-band high spectral resolution spectrometer has been developed for the charge-exchange recombination spectroscopy measurement on the HL-2. tokamak. The simultaneous measurements of He II(468.57 nm), C VI(52..1 nm), and Dα(656.1 nm accompanied by beam emission spectra) with an acquisition frequency up to 400 Hz are achieved by vertically binning the spectrum from each fiber in experiments. Initial results indicate that the system can provide radial profiles of not only ion temperature and rotation velocity,but also concentration of carbon. For the case of helium, the measurements for the ion temperature and rotation velocity are straightforward but the apparent concentration associated with the observed CX intensity is obviously too high. Modeling of the active He II CX feature including plume contributions needs to be carried out to extract the true helium *** spectrometer could become a prototype for the ITER charge-exchange recombination spectroscopy diagnostic and the pilot experiments, as presented here, demonstrate the possibility of impurity concentrations measurements based on the combined measurement of local beam emission and charge-exchange recombination spectroscopy spectra.

关键词： CXRS ion temperature plasma rotation impurity concentration

Special magnetic phenomena in heavily doped La_(0.7-x)Dy_xSr_(0.3)MnO_3 system

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Science china(physics,Mechanics & Astronomy) 2008年第1期51卷 90-97页

作者： LIU Ning 1,2.,YAN GuoQing 1,3 ,CAI ZhiRang 1 ,PI Li 2.,ZHANG Bei 2.&TONG Wei 2.1 Department of physics,Suzhou College,Suzhou 2.4000,china 2.Structure Research {2.,university of Science and Technology of china,Hefei 2.002.,china 3 National {2. of Solid State Microstructures,physics Department,Nanjing university,Nanjing 2.0093,china 1. Department of physics Suzhou College Suzhou 234000 China 2. Structure Research laboratory University of Science and Technology of China Hefei 230026 China 3. National laboratory of Solid State Microstructures Physics Department Nanjing University Nanjing 210093 China

The magnetism in heavily Dy doped La0.7-xDyxSr0.3MnO3(0.40≤x≤0.70)system is studied in this *** M-T relation seems to be complicated with the increase of *** sample with x=0.40,AFM behavior exists at T≤TN and M-T curves under zero field cooling(ZFC)and field cooling(FC)exhibit typical behavior of spincluster glass state above *** the sample with x=0.50,the M-T curve under ZFC exhibits a valley at a low temperature while the M-T curve under FC exhibits the negative magnetization below *** samples with x=0.60,0.70,their ZFC M-T curves are similar to that of x=0.50,but the FC M-T curves do not exhibit negative values any *** the peculiar phenomena above are well explained by Néel double-lattice model combined with M-H relation at typical *** molecular field theory fits well the negative magnetization for x=0.50.

关键词： heavily doped special magnetic phenomena double-lattice model

Pegmatite remote sensing extraction and metallogenic prediction in Azubai area,Xinjiang

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中国有色金属学会会刊：英文版 2011年第S3期21卷 543-548页

作者： PENG Guang-xiong1, 2. YE Zhen-chao1, 2. GAO Guang-ming1, 2. FENG De-shan1, XIONG Yun1 1. School of Geosciences and Info-physics, Central South university, Changsha 410083,{2. 2. Key laboratory of Metallogenic Prediction of Nonferrous Metals, Ministry of Education, Changsha 410083,{2. [a] School of Geosciences and Info-physics Central South University Changsha 410083 China [b] Key laboratory of Metallogenic Prediction of Nonferrous Metals Ministry of Education Changsha 410083 China

Remote sensing technique plays an important role in geological prospecting in Altay because of the remote location and steep terrain with mountains. Pegmatite has important implications for metallogenic prospecting as most of rare metals occurs in it. Pegmatite information from optical and radar images was extracted, and the spatial distribution and scale of pegmatite were generalized in Azubai, Altay. Three mining targets, that is, Halon-Azubai, Kuermutu-Tuyibaguo and Zhuolute-Akuoyige, were delineated based on the analysis of pegmatite information, structure interpretation and other geological data.

关键词： pegmatite remote sensing information extraction metallogenic prediction