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Synthesis of 5-[5-(α-Naphthyl)-2H-Tetrazol-2-Methylene]-2-Aroylamino-1, 3,4-Thiadiazoles

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Chemical Research in Chinese Universities 1992年第3期8卷 314-318页

作者： FENG Xiao-ming, CHEN Rong (department of Chemistry, South-west normal University, Chongqing)ZHANG Zi-yi (department of Chemistry, lanzhou University, lanzhou)

Introduction Acylthiosemicarbazides have been reported to possess extensive physiological activities. Substituted thiadiazoles are known to exhibit fungicidal and insecticidal activities. Chen Limin and her coworkers reported that the cyclization of 1[5-(3’-pyridyl )-2H-tetrazol-2-acetyl-]-4-acylthiosemicarbazides gave 5-[5-(3’-

关键词： Synthesis Acylthiosenlicarbazide Physiological activity Fungicidai and insecticidal activities

Discussion of the Realistic Tendency in Contemporary American Short Fiction

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兰州大学学报（社会科学版） 2000年第S1期28卷 196-201页

作者： Xu Ming 1 Guo Hong 2 (1 Foreign Languages department, Tianjin Engineering Institute, Tianjin, 300191 2 Foreign Languages department, Northwest normal University, lanzhou, 730073, china)

In the post World War Ⅱ decades, there is a strong realistic trend in American Short stories. The great achievement made by the new realistic short stories has contributed much to the post war flourishing of American... 详细信息

关键词： American short stories realistic trend post war thematics concern

STEADY-STATE SOLUTIONS FOR A ONE-DIMENSIONAL NONISENTROPIC HYDRODYNAMIC MODEL WITH NON-CONSTANT LATTICE TEMPERATURE

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Acta Mathematica Scientia 2008年第3期28卷 479-488页

作者：黎野平 department of Mathematics Xianning College

A one-dimensional stationary nonisentropic hydrodynamic model for semiconductor devices with non-constant lattice temperature is studied. This model consists of the equations for the electron density, the electron current density and electron temperature, coupled with the Poisson equation of the electrostatic potential in a bounded interval supplemented with proper boundary conditions. The existence and uniqueness of a strong subsonic steady-state solution with positive particle density and positive temperature is established. The proof is based on the fixed-point arguments, the Stampacchia truncation methods, and the basic energy estimates.

关键词： Steady-state nonisentropic hydrodynamic model semiconductor subsonic

α-范数下非局部脉冲发展方程mild解的存在性

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山东大学学报（理学版） 2011年第11期46卷 70-74,95页

作者：杨和西北师范大学数学与信息科学学院甘肃兰州730070

讨论非线性脉冲发展方程非局部问题u'(t)+Au(t)=f(t,u(t),Gu(t)),t∈[0,T],t≠tk,Δu|t=tk=Ik(u(tk)),k=1,2,…,m,0 详细信息

讨论非线性脉冲发展方程非局部问题u'(t)+Au(t)=f(t,u(t),Gu(t)),t∈[0,T],t≠tk,Δu|t=tk=Ik(u(tk)),k=1,2,…,m,0

关键词：脉冲发展方程非局部条件 mild解紧解析半群 α-范数

Theory study of shapes in ^(187,189)Tl nuclei

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Science china(Physics,Mechanics & Astronomy) 2009年第6期52卷 818-821页

作者： LIU YanXin1, YU ShaoYing1,2,3, SHEN CaiWan1,5 & DONG YongSheng1,2,4 1 School of Science, Huzhou Teachers college, Huzhou 313000, china 2 School of Science and Information Engineering, Zhejiang normal University, Jinhua 321000, china 3 Institute of Theoretical Physics, Chinese Academy of Sciences, Beijing 100080, china 4 department of Physics, Jining Teachers college, Jining 012000, china 5 Center of Theoretical Nuclear Physics, National Laboratory of Heavy Ion Accelerator of lanzhou, lanzhou 730000, china School of Science Huzhou Teachers College Huzhou China School of Science and Information Engineering Zhejiang Normal University Jinhua China Institute of Theoretical Physics Chinese Academy of Sciences Beijing China Center of Theoretical Nuclear Physics National Laboratory of Heavy Ion Accelerator of Lanzhou Lanzhou China department of Physics Jining Teachers College Jining China

The nuclear shapes of 187,189Tl were investigated theoretically in this work. The total routhian surface (TRS) calculations were performed for N=106 and 108 isotopes of thallium (Z=81). The single-particle energies were obtained from the deformed Woods-Saxon potential, with the Lipkin-Nogami (LN) treatment of pairing. It is found that the collective oblate rotation coexists with the high-K prolate rotation. Superdeformed prolate rotation is included in this calculation.

关键词： nuclear shape oblate rotation prolate rotation

STUDIES ON THE REACTION OF SULFUR,SELENIUM AND TELLURIUM WITH SODIUM HYDROXIDE UNDER PHASE TRANSFER CATALYSIS(Ⅱ).A CONVENIENT METHOD FOR THE SYNTHESIS OF BI(ACYL)DISULFIDES

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Chinese Chemical Letters 1990年第3期1卷 193-196页

作者： Jin-Xian WANG(Chin-Hsien WANG) Wenfeng CUI Yulai HU Kai ZHAO Institute of Chemistry,department of Chemistry,Northwest normal University,lanzhou,730070

A simple and general method for the synthesis of bi(acyl)disulfides is *** is allowed to react with sodium hydroxide to give sodium disulfide at 65℃ under PTC,which can react with acyl halides to afford bi(acyl)disul... 详细信息

关键词： In Wang ACYL)DISULFIDES STUDIES ON THE REACTION OF SULFUR,SELENIUM AND TELLURIUM WITH SODIUM HYDROXIDE UNDER PHASE TRANSFER CATALYSIS A CONVENIENT METHOD FOR THE SYNTHESIS OF BI PEG OC Ph

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 School of Geography South China Normal University Guangzhou China Key Laboratory of Oasis Ecology (Ministry of Education) Xinjiang University Urumqi China Key Laboratory of Western china’s Environmental Systems (Ministry of Education) Lanzhou University Lanzhou China

The climate over the closed inland Barkol Lake, which is located in northeastern Xinjiang Uygur Autonomous Region, is sig- nificantly influenced by westerly winds today. To improve our understanding of past climate processes in westerly wind influenced regions in northwestern china, a 250-cm sediment section was retrieved from this lake. After 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 BP. Multi-proxy datasets, including δ^18Ocar, δ^13Ccar of authigenic carbonate, and total organic carbon were examined using wavelet analysis and singular spectrum analysis methods. Results 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 BP. The general trend of Holocene climatic changes revealed by Barkol Lake sediments was in agreement with that of adjacent regions. We 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 Nifio/La Nifia-Southern Oscillation. This study demonstrates that the enhanced activities of ENSO may have played an important role in climatic changes in northeastern Xinjiang during the Holo- cene. Our 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 relat

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

Modified PFA with the Azimuth Resampling in Post Fourier Transformed Data Domain

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Modified PFA with the Azimuth Resampling in Post Fourier Tra...

Non-isothermal decomposition kinetics and lifetime of Tb2(0-MBA)6(PHEN)2

2012 National Conference on Information Technology and computer Science

作者： Liang Lu,Pan Li department Information Engineering lanzhou Vocational Technical college No.37 Anning Liusha Road,lanzhou,730070,china college of Physics and Electronic Engineering Northwest normal University No.967 Anning East Road,lanzhou,730070,china

The polar format algorithm （PFA） is the most popular way for spotlight synthetic aperture radar （SAR） image formation and is still attractive ***,the algorithm is carried out sequentially as a range resampling,an azimuth resampling,a Fourier transform （FT） in azimuth,and an FT in ***,this procedure usually leads to zerospadding in the azimuth resampled data domain,and consequently degrades final image *** this paper,a modified PFA with the azimuth resampling in post azimuth Fourier transformed data domain,as opposed to traditionally done in pre-transformed domain is *** modification relies on the frequency scaling property of the *** ensure the efficiency of the PFA,we adopt the fast FT （FFT） based scaling scheme for the azimuth ***,a processing flow is proposed for real time *** proposed PFA performs well and efficiently in the imaging of simulated and real spotlight SAR data.

关键词： spotlight synthetic aperture radar (SAR) polar format algorithm (PFA) Fourier transform (FT)

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Rare Metals 2003年第3期22卷 155-159页

作者： ZHANGJianjun BAIJihai WANGRuifen WANGShuping LIJibiao ExperimentalCenter NormalUniversityShijiazhuang050016China departmentofcomputer HebeiNormalCollegeofScienceandTechnologyChangli066600China departmentofChemistry HebeiNormalUniversityShijiazhuang050091China

The thermal decomposition of Tb_2(O-MBA)_6(PHEN)_2 (O-MBA: o-methylbenzoate;PHEN: 1,10-phenanthroline) and its kinetics were studied under the non-isothermal condition bythermogravimetry-derivative thermogravimetry (TG-DTG) techniques. Kinetic parameters were obtainedfrom analysis of TG-DTG curves by the Achar method and the Madhusudanan-Krishnan-Ninan (MKN) *** most probable mechanism function was suggested by comparing the kinetic parameters. The kineticequation for the first stage can be expressed as dα/dt = Aexp(-E/RT)·3(1 - α)^(2/3). Thelifetime equation at mass loss of 10% was deduced as lnτ= -28.7429 + 19797.795/T by isothermalthermogravimetric analysis.

关键词： thermochimica non-isothermal kinetics TG-DTG terbium complex O-methylbenzoate 1,10-phenanthroline