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FeS_(2. (pyrite) electrodeposition thin films and study of growth mechanism

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Science china(Technological Sciences) 2005年第6期48卷 601-611页

作者： DONG Youzhong1, ZHENG Yufeng1, ZHANG Xiaogang2. DUAN He1, SUN Yanfei1 & CHEN Yanhua1 1. Department of Physics, xinjiang university,{2., china 2. institute of applied chemistry, xinjiang university,{2., china 1. Department of Physics Xinjiang University 830046 Urumqi China 2. institute of applied {2. Xinjiang University 830046 Urumqi China

Ferrous sulfide (FeS) thin films were initially electrodeposited on indium-tin oxide (ITO) substrates in the aqueous solution containing iron, sulfur elements and then annealed in the sulfur atmosphere. Thereby, we successfully obtained the single-phased iron pyrite (FeS2. thin films with good quality. The experimental parameters for electrodeposition and the post-growth thermal-dynamical conditions have been calculated so that more details about the effect of thermal-dynamical conditions on the micromechanism concerned with the iron pyrite crystal growth as well as the properties of the samples have been discussed.

关键词： electrodeposition, FeS2 (pyrite), thin films, growth dynamics.

Local electronic structure and magnetic properties of 3d transition metal doped GaAs

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Science china(Physics,Mechanics & Astronomy) 2008年第5期51卷 470-480页

作者： LIN He1 & DUAN HaiMing2. Department of chemistry,institute of {2. chemistry,xinjiang university,urumqi 830046,china 2.epartment of Physics,xinjiang university,urumqi 830046,china 1. Department of chemistry Institute of Applied Chemistry Xinjiang University Urumqi 830046 China 2. Department of Physics Xinjiang University Urumqi 830046 China

The local electronic structure and magnetic properties of GaAs doped with 3d transition metal (Sc, Ti, V, Cr, Mn, Fe, Co, Ni) were studied by using discrete variational method (DVM) based on density functional theory. The calculated result indicated that the magnetic moment of transition metal increases first and then decreases, and reaches the maximum value when Mn is doped into GaAs. In the case of Mn concentration of 1.4%, the magnetic moment of Mn is in good agreement with the experimental result. The coupling between impure atoms in the system with two impure atoms was found to have obvious variation. For different transition metal, the coupling between the impure atom and the nearest neighbor As also has different variation.

关键词： diluted magnetic semiconductor density functional theory 3d transition metal cluster model electronic structure

Effects Of Ultrasound On Voltammetric Measurements At An Ag Cylinder Electrode

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Chinese Chemical Letters 1998年第7期9卷 663-666页

作者： Xiao Gang ZHANG Wan Yong ZHOU Chao Ying GENG Xi XIA (institute of applied {2., xinjiang university, Wulumqi 830046) xinjiang Univ Inst Appl Chem Wulumqi 830046 Peoples R China

In this paper,the voltammetric behaviours of Ag cylinder electrode in 1 mol/dm(3) KOH solution have been investigated in the presence of ultrasound irradiation. The results based on the CV, EIS and polarization measurements showed that ultrasound could enhance the mass transport, inhibit the oxygen evolution and increase the exchange current.

关键词： sonoelectrochemistry ultrasound irradiation Ag electrode voltammetric behaviours

Identifying the geographical origin and processing technology of Moyao(Myrrh)on the basis of near-infrared spectroscopy combined with chemometrics

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Journal of Traditional Chinese Medicine 2024年第3期44卷 505-514页

作者： XU Ningning YAN Ganming XU Fengjie DENG Linfeng QIAO xinjiang LU Changzheng CHENG Shaomin TCM Diagnosis institute College of Traditional Chinese MedicineJiangxi University of Chinese MedicineNanchang 330004China TCM Processing institute Pharmaceutical CollegeJiangxi University of Chinese medicineNanchang 330004China School of Electronic Information and Artificial Intelligence Shaanxi University of Science and TechnologyXi'an 710021China Jiangzhong Pharmaceutical Co. Ltd.Nanchang 330096China Jiangxi Guhan Refined Chinese Herbal Pieces Co. Ltd.Nanchang330041.China

OBJECTIVE:To evaluate the quality of Moyao(Myrrh)in the identification of the geographical origin and processing of the ***:Raw Moyao(Myrrh)and two kinds of Moyao(Myrrh)processed with vinegar from three countries were identified using near-infrared(NIR)spectroscopy combined with chemometric *** component analysis(PCA)was used to reduce the dimensionality of the data and visualize the clustering of samples from different categories.A classical chemometric algorithm(PLS-DA)and two machine learning algorithms[K-nearest neighbor(KNN)and support vector machine]were used to conduct a classification analysis of the near-infrared spectra of the Moyao(Myrrh)samples,and their discriminative performance was ***:Based on the accuracy,precision,recall rate,and F1 value in each model,the results showed that the classical chemometric algorithm and the machine learning algorithm obtained positive *** all of the chemometric analyses,the NIR spectrum of Moyao(Myrrh)preprocessed by standard normal variation or Multivariate scattering correction combined with KNN achieved the highest accuracy in identifying the geographical origins,and the accuracy of identifying the processing technology established by the KNN method after first-order derivative pretreatment was the *** best accuracy of geographical origin discrimination and processing technology discrimination were 0.9853 and 0.9706 ***:NIR spectroscopy combined with chemometric technology can be an important tool for tracking the origin and processing technology of Moyao(Myrrh)and can also provide a reference for evaluations of its quality and the clinical use.

关键词： Moyao(Myrrh) near-infrared spectroscopy geographical origin processing technology

Synthesis,characterization,properties and crystal structure of heterometallic 1D coordination polymers {[CuLZn·CuLZn(H_2.)]·H_2.}_n

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Science china chemistry 2006年第4期49卷 338-344页

作者： TAO Ruojie1, LI Fu’an1, ZANG Shuangquan1, CHENG Yanxiang2.& NIU Jingyang1 1. chemistry and Chemical Engineering College of Henan university, Kaifeng 475001,{2. 2. Changchun institute of applied chemistry, Chinese Academy of Sciences, Changchun 13002.,{2. 1. chemistry and Chemical Engineering College of Henan university Kaifeng 475001 China 2. Changchun institute of applied {2. Chinese Academy of Sciences Changchun 130022 China

Copper-zinc heterometallic 1D chain coordination polymer has been synthesized and characterized by elemental analysis, and IR spectra etc. The crystal structure was determined by single-crystal X-ray diffraction analyses. The title complex is 1D chain coordination polymer with the chemical formula {[CuLZn·CuLZn(H2.)]·H2.}n, where H4L=N-(2.hydroxybenzamido)-N’-(3-carboxy- lsalicylidene)ethylenediamine. Its structural unit is comprosed of two tetranuclear cycles formed by two dissymmetrical tetranuclear units. These units polymerized each other to form 1D chain coordi- nation polymer.

关键词： copper, zinc, heterometallic coordination polymer, crystal structure.

Synthesis and crystal structure of complex of Ce(NO_3)_3 with N-(3-methyl-pyridin-2.yl)-formimidoyl-(3-methyl-pyridin-2.yl) hydrazone

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Science china chemistry 2004年第3期47卷 251-256页

作者： JIANG Yinzhi1,2.& HU Weixiao1 1. Department of Pharmaceutical Science, Zhejiang university of Technology, Hangzhou 310032. china 2. Department of {2. chemistry, Zhejiang institute of Science and Technology, Hangzhou 310033, china 1. Department of Pharmaceutical Science Zhejiang University of Technology 310032 Hangzhou China 2. Department of applied chemistry Zhejiang Institute of Science and Technology 310033 Hangzhou China

The reaction of 3,6-di-(3-methyl-pyridin-2.yI)-s-tetrazine (DMPTZ, II) with CeIII salt [Ce(NO3)3 · 6H2.] generates a new ligand, N-(3-methyl-pyridin-2.yl)-formimidoyl-(3-methyl-pyridin-2.yl) hydrazone (L), and forms a new complex: a mononuclear complex [Ce(L)(NO3)2.(H2.)3] · NO3 (III). Crystal data for III: space group P-1, with a = 0.7133(4) nm, b = 1.1139(2. nm, c = 1.4572.3) nm, α= 102.13(2.°, β= 99.81(3)°, γ= 91.10(3)°, Z = 2. V = 1113.6(7) nm3, μ = 2.12. mm?1 and F(000) = 630. L acts as a tri-dentate chelating ligand in III. There are 10 coordination sites around Ce3+ of III, which are respectively occupied by seven oxygen atoms (four from two nitrate anions and three from three H2. molecules) and three nitrogen atoms (all from L). The cerium atom and three chelating nitrogen atoms are coplanar. The mechanism of the metal assisted decomposition is discussed briefly.

关键词： rare earth, complex, crystal structure, synthesize, 3,6-bis (3-methyl-pyridin-2.yl)-s-tetrazine, N-(3-methyl-pyridin- 2.yl)-formimidoyl-(3-methyl-pyridin-2.yl) hydrazone.

Climate instability in the Yili region, xinjiang during the last glaciation

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Chinese Science Bulletin 2000年第17期45卷 1604-1609页

作者： YE Wei, DONG Guangrong, YUAN Yujiang & MA Yingjie1. xinjiang institute of Ecology and Geography, Chinese Academy of Sciences, {2. 830011, china 2. Department of Geography, Zhejiang Normal university, Jinhua 32.004, china 3. institute of Desert Research, Chinese Academy of Sciences, Lanzhou 730000, china 4. xinjiang institute of Meteorological Research, {2. 830002. china xinjiang institute of Ecology and Geography Chinese Academy of Sciences Urumqi China Department of Geography Zhejiang Normal University Jinhua China institute of Desert Research Chinese Academy of Sciences Lanzhou China xinjiang institute of Meteorological Research Urumqi China

The climate is influenced by westerlies year in year out and the aeolian loess is widespread in the Yili region, the xinjiang Uygur Autonomous Region. Through the study of the loess section with a thickness of 2..5 m, much useful information about climatic change in this region during the last glaciation was gotten. Grain size analysis of loess samples in the section showed that the climatic change in the Yili region was of instability during the last glaciation and similar to those of the North Atlantic Ocean and Greenland. In correspondence with the Heinrich events, the percentage of the size fraction of loess with grain size less than 10 μm decreased in cold stadials in the Yili region. This result suggests that the westerly wind be strengthened during the cold periods. Compared with the stadials, the content of the loess with grain size less than 10 μm was increased in interstadials, which indicated that the strength of the westerly wind was weakened. It is obvious that the climate was instable

关键词： Yili region last glaciation climate instability.

Impact Assessment and Protection of Outstanding Landscape Integrity in a Natural Heritage Site:Fairy Valley,Kanas Nature Reserve,xinjiang,china

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Journal of Mountain Science 2011年第1期8卷 46-52页

作者： HAN Fang1,2.YANG Zhaoping1,LIU Xinyu1,2.DI Feng3 1 xinjiang institute of Ecology and Geography,Chinese Academy of Sciences,{2. 830011,china 2.Graduate university of Chinese Academy of Sciences,Beijing 100049,china 3 xinjiang Department of Science and Technology,{2. 830011,china xinjiang institute of Ecology and Geography Chinese Academy of Sciences Urumqi China Graduate university of Chinese Academy of Sciences Beijing China xinjiang Department of Science and Technology Urumqi China

The essential purpose of the Convention Concerning the Protection of World Cultural and Natural Heritage is to protect the integrity of heritage *** landscape is the core embodiment of the aesthetic value of a natural heritage *** paper proposes a new assessment method from the point of view of the protection of heritage *** is used to measure the degree of outstanding landscape integrity under the human and natural impact in natural heritage *** paper employ three indices,a visual index of outstanding landscape,a harmony index of the artificial landscape and a disturbance index of damaged landscape,to measure the impact of landscape *** impact assessment model is based on a weighted combination of the three *** study site is the Fairy Valley,Kanas Nature Reserve,xinjiang Uygur Autonomous Region in northwest *** information employed is derived from field investigation and a Digital Elevation Model(DEM).A comprehensive evaluation of the Fairy valley was undertaken and it was determined that the outstanding landscape values are being *** protection methods are proposed to reduce the adverse effects and maintain landscape quality,thereby providing site managers with suggestions for the protection of natural heritage *** broadly,the paper contributes novel methods of landscape assessment applicable to natural protected areas.

关键词： Landscape integrity Landscape impact assessment Landscape protection Natural heritage site Kanas Nature Reserve xinjiang

A complex variable meshless method for fracture problems

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Science china(Physics,Mechanics & Astronomy) 2006年第1期49卷 46-59页

作者： CHENG Yumin1 & LI Jiuhong2.1. Shanghai institute of applied Mathematics and Mechanics, Shanghai {2., Shanghai 2.0072. china 2. Department of Building Engineering, Xi’an {2. of Technology, Xi’an 710048, china Shanghai institute of applied Mathematics Mechanics Shanghai University Shanghai 200072 China Department of Building Engineering Xi’an University of Technology Xi’an 710048 China

Based on the moving least-square (MLS) approximation, the complex variable moving least-square approximation (CVMLS) is discussed in this paper. The complex variable moving least-square approximation cannot form ill-conditioned equations, and has greater precision and computational efficiency. Using the analytical solution near the tip of a crack, the trial functions in the complex variable moving least-square approxi- mation are extended, and the corresponding approximation function is obtained. And from the minimum potential energy principle, a complex variable meshless method for fracture problems is presented, and the formulae of the complex variable meshless method are obtained. The complex variable meshless method in this paper has greater precision and computational efficiency than the conventional meshless method. Some examples are given.

关键词： moving least-square approximation, complex variable moving least-square approximation, meshless method, complex variable meshless method, fracture.