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Chinese Chemical Letters 1997年第5期8卷 455-458页

作者： Cun SHAN Dian Zen JIA Xi XIA(Department of Chemistry,, xinjiang university, urumqi,830046). Department of Chemistry Xinjiang University Urumqi 830046 China

The paper reports the synthetic procedure and character of Copper(II) binuclearcoordination compound of 1,4-bis-(1'-phenyl-3'-methyl-5'-pyrazolone Thenon-isothermal kinetics of thermal decomposition of the complex has been stUdied from the TG-DTGcurves by means of the Achar et al. and Coats-Redfern methods,the most probab1e kinetic equation canbe expressed as dofdtrAe -E / RT * l /(2Q).The corresponding kinetic compensation effect expressions arefound to be lnuA=0. 1794E+0. *** non-isothermal thermal decomposition process of the complex isone-dimensional *** electrochemical studies of the complex(Cu2L'2)from cyclic voltamrnetriccurves by means of powder microelectrodes technique'',shows one two-electron irreversible process.

关键词： Methyl-5 Phenyl-3 Pyrazolone-4 Synthesis Characterization Non-isothermal Kinetics of the Thermal Decomposition and Redox Properties Derived from Copper Binuclear Coordination Compound of 1,4-Bis

A NOTE ON THE PAPER “UNIFORM PERSISTENCE IN DISCRETE SEMIDYNAMICAL SYSTEM AND ITS APPLICATION”

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Systems Science and Mathematical Sciences 1999年第2期12卷 145-148页

作者： TENG Zhidong(Department of Mathematics, xinjiang university, urumqi 830046, china) 新疆大学数学系新疆乌鲁木齐

In this paper, we study the uniform persistence of a class of two dimensional periodic Kolmogorov ecosystems. As an improvement on a main result in [1] we obtain a new criterion of the uniform persistence for solutions.

关键词： Kolmogorov system periodic uniform persistence unbounded ultimate bound.

A Fast quarter-pixel motion estimation algorithm for H.264/AVC

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Optoelectronics Letters 2008年第1期4卷 66-68页

作者： CHEN Gang,JIA Zhen-hong,and CHEN He School of Information Science and Engineering, xinjiang university, urumqi 830046, china School of Information Science and Engineering Xinjiang University Urumqi 830046 China

A fast quarter-pixel motion estimation algorithm is proposed in this paper. The proposed algorithm based on mathematical models of the motion compensated prediction errors. Unlike conventional quarter-pixel accurate motion estimation algorithm, proposed algorithm can avoid fractional-pixel interpolation and subsequent fractional-pixel search after integer-precision motion estimation. Experiments show that the proposed algorithm greatly reduces the computational complexity of quarter- pixel motion estimation, while keeping the nearly equal quality of the

关键词：四分之一像素运动估计算法数学模型 H.264/AVC 图像信号处理

The Silk Road and East-West Cultural Exchange

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china Book International 2024年第2期 52-57页

作者： Rong xinjiang Department of History Peking University Center for Ancient Chinese History Peking University British Academy Dunhuang and Turpan Society of china

To the east and south of china lies the ocean,to the west are deserts and mountains,and to the north are the Gobi Desert and forests,placing it in a relatively enclosed geographical environment,which is not conducive to communication with the outside ***,china has never been self-isolated;through both the terrestrial and maritime Silk Road,it has maintained extensive contact with the external world,both contributing to and absorbing *** the historical process of East-West cultural exchange,the Silk Road played an extremely important role.

关键词： Silk West maintained

Holocene climate variation denoted by Barkol Lake sediments in northeastern xinjiang and its possible linkage to the high and low latitude climates

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Science china Earth Sciences 2011年第4期54卷 603-614页

作者： XUE JiBin & ZHONG Wei 1 School of Geography,South china Normal university,Guangzhou 510631,china 2 Key Laboratory of Oasis Ecology(Ministry of Education) ,xinjiang university,urumqi 830046,china 3 Key Laboratory of Western china's Environmental Systems(Ministry of Education) ,Lanzhou university,Lanzhou 730000,china 1. School of Geography South China Normal University Guangzhou 510631 China2. Key Laboratory of Oasis Ecology (Ministry of Education) Xinjiang University Urumqi 830046 China3. Key Laboratory of Western China’s Environmental Systems (Ministry of Education) Lanzhou University Lanzhou 730000 China

The climate over the closed inland Barkol Lake,which is located in northeastern xinjiang Uygur Autonomous Region,is significantly influenced by westerly winds *** improve our understanding of past climate processes in westerly wind influenced regions in northwestern china,a 250-cm sediment section was retrieved from this *** taking the carbon reservoir effect into consideration,the chronological sequence of this section was reconstructed based on seven conventional radiocarbon dates of bulk samples,and the bottom age of this section was determined to be about 9400 cal a ***-proxy datasets,includingδ18O car,δ13C car of authigenic carbonate,and total organic carbon were examined using wavelet analysis and singular spectrum analysis *** show that the Holocene in the Barkol Lake region can be divided into four stages:(1) a cold and dry early stage before～8000 cal a BP;(2) a moderately warm and wet middle stage between～8000 and 6000 cal a BP;(3) a warm and dry stage,along with a cooling-wetting tendency from 6000 to 2700 cal a BP;and(4) a fluctuating cooling and wet stage between 2700-800 cal a BP,and a drier stage since 800 cal a *** general trend of Holocene climatic changes revealed by Barkol Lake sediments was in agreement with that of adjacent *** infer that climatic changes during the Holocene in the Barkol Lake region were influenced not only by high latitudes,especially the North Atlantic region climate,but also tropical low-latitude processes,such as the El Nio/La Nia-Southern *** study demonstrates that the enhanced activities of ENSO may have played an important role in climatic changes in northeastern xinjiang during the *** results also suggest that climatic patterns may be temporally different in the northern xinjiang area in response to the changing predominant control of either the Westerly or the Asian summer monsoon,depending on the contrast of their relative strengths.

关键词： Barkol Lake Holocene climate change tropical processes northern high-latitude climate

TIME-DEPENDENT COOPERATIVE SYSTEM OFPOPULATION GROWTH

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Systems Science and Mathematical Sciences 1998年第3期11卷 204-209页

作者： CUI Jingan DUAN Kuichen(Department of Mathematics, xinjiang university, urumqi 830046, china) 新疆大学数学系新疆乌鲁木齐

In this paper, we consider the asymptotic behavior of a general time-dependent cooperative system. Sufficient condition is obtained for the existence of a globally attractive positive periodic solution when the system... 详细信息

关键词： Cooperative system globally attractive periodic solution Poincare mapping

Role of self-assembled molecules’anchoring groups for surface defect passivation and dipole modulation in inverted perovskite solar cells

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Chinese physics B 2024年第10期33卷 108-115页

作者： Xiaoyu Wang Muhammad Faizan Kun Zhou xinjiang Wang Yuhao Fu Lijun Zhang Key Laboratory of Superhard Materials College of PhysicsJilin UniversityChangchun 130012China State Key Laboratory of Integrated Optoelectronics Key Laboratory of Automobile Materials of MOECollege of Materials Science and EngineeringJilin UniversityChangchun 130012China

Inverted perovskite solar cells have gained prominence in industrial advancement due to their easy fabrication,low hysteresis effects,and high *** these advantages,their efficiency is currently limited by excessive defects and poor carrier transport at the perovskite-electrode interface,particularly at the buried interface between the perovskite and transparent conductive oxide(TCO).Recent efforts in the perovskite community have focused on designing novel self-assembled molecules(SAMs)to improve the quality of the buried ***,a notable gap remains in understanding the regulation of atomic-scale interfacial properties of SAMs between the perovskite and TCO *** understanding is crucial,particularly in terms of identifying chemically active anchoring *** this study,we used the star SAM([2-(9H-carbazol-9-yl)ethyl]phosphonic acid)as the base structure to investigate the defect passivation effects of eight common anchoring groups at the perovskite-TCO *** findings indicate that the phosphonic and boric acid groups exhibit notable *** groups fulfill three key criteria:they provide the greatest potential for defect passivation,exhibit stable adsorption with defects,and exert significant regulatory effects on interface *** anchoring groups exhibit enhanced passivation capabilities for defect energy levels due to their superior Lewis base properties,which effectively neutralize local charges near *** various defect types,iodine vacancies are the easiest to passivate,whereas iodine-substituted lead defects are the most challenging to *** study provides comprehensive theoretical insights and inspiration for the design of anchoring groups in SAMs,contributing to the ongoing development of more efficient inverted perovskite solar cells.

关键词： inverted perovskite solar cell defect passivation self-assembled molecule interface engineering first-principles calculation

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,urumqi 830011,china 2 Graduate university of Chinese Academy of Sciences,Beijing 100049,china 3 xinjiang Department of Science and Technology,urumqi 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

THE SEQUENCE OF PALEOENVIRONMENTAL CHANGES SINCE ABOUT 4KA B.P., RECORDED BY NIYA SECTION IN SOUTHERN MARGIN OF TARIM BASIN

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Chinese Geographical Science 2001年第2期11卷 144-149页

作者： ZHONG Wei, XIONG Hei-gang, TASHPOLAT Tiyip, SHU Qiang （Department of Geography, xinjiang university,urumqi 830046, P.R. china） Department of Geography Xinjiang University Urumqi P.R. China

Through synthetic researches of multi-index geological records of Niya section, which are of high resolution in southern margin of Tarim Basin, this paper has reconstructed the sequences of paleoclimate in this region during historical times (since about 4000a B.P.). During the last 4000 years, the area has experienced alternations of relative cold-moisture and relative warm-dry periods. Three evident cold-moisture periods and three warm-dry periods are identifing. The study shows that the human activities have an intimate relation with the evolution of paleoclimate in the southern xinjiang. Paleoclimate has played very important role in influencing human being′s agricultural activities.

关键词： southern margin of Tarim Basin Niya section historical times climatic evolution

Strong pulses from pulsar PSR J0034-0721

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Research in Astronomy and Astrophysics 2011年第8期11卷 974-980页

作者： Adili Tuoheti Ali Esamdin Hui-Dong Hu Guo-Liang Lv Na Wang Mamat Abliz Department of physics Xinjiang University Urumqi 830046 China xinjiang Astronomical Observatory Chinese Academy of Sciences Urumqi 830011 China xinjiang university-National Astronomical Observatories Joint Center For Astrophysics Urumqi 830046 China

We present an analysis of strong single pulses from PSR J0034-0721. Our observations were made using the urumqi 25-m radio telescope at a radio frequency of 1.54 GHz. A total of 353 strong pulses were detected during eight hours of observing, The signal-to-noise ratios of the detected pulses range from 5 to 11.5. The peak fluxes of those pulses are 17 to 39 times that of the average pulse peak. The cumulative distribution of the signal-to-noise ratios of these strong pulses has a rough power-law distribution with a slope of 4.4 q- 0.5. Ten of the strong pulses arrived approximately 23 to 40 ms earlier than the average profile peak. This suggests the possibility that there are two strong pulse-emitting regions.

关键词： pulsars: PSR J0034-0721 individual pulses: strong pulses