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Science china Chemistry 2009年第8期52卷 1171-1175页

作者： XU GaoChao,LIU RuiQuan & WANG Jin College of Chemistry and Chemical Engineering,xinjiang university,urumqi 830046,china College of Chemistry and Chemical Engineering Xinjiang University Urumqi 830046 China

Samaria-doped ceria Ce0.8Sm0.2O2-δ(SDC) and SmFe0.7Cu0.3-xNixO3 have been synthesized by the sol-gel method and characterized by X-ray diffraction(XRD),transmission electron microscopy(TEM) and scanning electron microscopy(SEM).The electrochemical synthesis of ammonia was investigated at atmospheric pressure and low temperature,using the SFCN materials as the cathode,a Nafion membrane as the electrolyte,nickel-doped SDC(Ni-SDC) as the anode and silver-platinum paste as the current *** was synthesized from 25 to 100℃ when the SFCN materials were used as cathode,with SmFe0.7Cu0.1Ni0.2O3 giving the highest rates of ammonia *** maximum rate of evolution of ammonia was 1.13 × 10-8 mol·cm-2·s-1 at 80℃,and the current efficiency reached as high as 90.4%.

关键词： electrochemical synthesis of ammonia ammonia synthesis at atmospheric pressure and low temperature Nafion membrane metal oxide

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

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

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

A Classical Toda Family with a Common Virasoro Symmetry Algebra

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Communications in Theoretical physics 2004年第6期41卷 813-815页

作者： QIAN Xian-Min LOU Sen-Yue ~1department of physics,Shanghai Jiao Tong university,Shanghai 200030,china ~2department of physics,Shaoxing College of Arts and Sciences,Shaoxing 312000,china department of physics,Ningbo university,Ningbo 315211,china department of physics Ningbo University Ningbo 315211 China

By means of a simple ideal,which is firstly proposed for the continuous system,we present an arbitraryorder classical Toda family invariant under common Virasoro-type symmetry algebra.

关键词： classical Toda family Virasoro symmetry algebra

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

Particle tunnels across the horizon of Garfinkle-Horowitz-Strominger dilaton black hole

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Science china(physics,Mechanics & Astronomy) 2007年第5期50卷 601-610页

作者： FANG HengZhong1 & ZHAO Zheng2 1 department of physics, china university of Petroleum, Dongying 257061, china 2 department of physics, Beijing Normal university, Beijing 100875, china department of physics China University of Petroleum Dongying 257061 China department of physics Beijing Normal University Beijing 100875 China

We promote the work of Parikh and Wilczek on the black hole radiation to the emission of massive and charged particles from Garfinkle-Horowitz-Strominger black hole. The energy and charge of the space-time are conservational during the course of the evaporation. The calculation shows that the emission spectrum is not precisely thermal, while has a correction, and the conclusion supports the view- point of information conservation.

关键词： Hawking radiation, black body spectrum, barrier, information loss, entropy of black hole, Komar energy

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

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