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Catalytic properties of tungsten oxycarbide and carbide in hydrocarbon conversion

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Chinese Journal of chemistry 1990年第3期8卷 207-214页

作者： GAO,Zi QIN,Dai-Yi department of chemistry,Fudan {2.,Shanghai 2.0433

Tungsten oxycarbide with specific surface area 2. m^2.g was prepared from white tungstic acid by reduction and carburization with CO and H_*** and EXAFS measurements confirmed that the WOC obtained has a simple hexagonal structure isotypic with α-WC and the oxygen is inserted into the trigonal prismatic interstices of the crystal *** reactions of n- hexane,n-heptane and cyclohexane on WOC were studied and compared with WC prepared by direct synthesis at high temperature,WOC and WC are active for the hydrogenolysis,isomerization and dehydrocyclization of alkanes and dehydrogenation of cyclohexane and their catalytic properties are in many ways similar to Pt *** insertion inhibits the catalytic activities of tung- ten carbide for hydrocarbon conversion reactions probably due to electronic effect.

关键词： WOC EXAFS

The Fault Sonic Diagnosis of the Pressure Hammer with Artificial Diamond

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Wuhan university Journal of Natural Sciences 1999年第2期4卷 31-35页

作者： HU Yao gai 1,LI Kai yang 1, ZHONG Yu ning 2.1. department of Analysis Measurement Science ,Wuhan university ,Wuhan 430072.China 2. department of Mechanical Engineering ,Hubei Polytechnic university ,Wuhan 430068,China Wuhan university Department of Analysis-Measurement Science Wuhan China (GRID:grid.49470.3e) (ISNI:***) Hubei Polytechnic university Department of Mechanical Engineering Wuhan China (GRID:grid.410651.7) (ISNI:***)

Time series analysis and time domain statistics applied to the fault sonic diagnosis of the pressure hammer with artificial diamond is *** method with the characters of brief criterion,high accuracy and quick speed is... 详细信息

关键词： time series analysis AR( n ) model peak value probabilistics

Receptor subtype involved in α-adrenergic receptor-mediated Ca2. signaling in cardiomyocytes

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Acta Pharmacologica Sinica 2007年第7期 968-974页

作者： Da-li LUO~(2.3,4),Jian GAO~2.Lin-lin FAN~2.Yu TANG~2.You-yi ZHANG~3,Qi-de HAN~3~2.department of Pharmacology,School of Chemical Biology and Pharmaceutical Sciences,Capital university of Medical Sciences,Beijing100069,China ~3 Institute of Cardiovascular Science at the Health Science Center,Peking university,Beijing 100083,China

Aim:The enhancement of intracellular Ca2.signaling in response to α1-adrener-gic receptor （α1-AR） stimulation is an essential signal transduction event in theregulation of cardiac functions,such as cardiac growth,cardiac contraction,andcardiac adaptation to various *** present study was intended todetermine the role（s） of the α1-AR subtype（s） in mediating this ***:We evaluated the effects of subtype-specific agonists and antagonists of the α1-AR on the intracellular Ca2.signaling of neonatal rat ventricular myocytes usinga confocal ***:After being cultured for 48 h,the myocytesexhibited spontaneous local Ca2.release,sparks,and global Ca2.*** of the α1-AR with phenylephrine,a selective agonist of the α1-AR,dose-dependently increased the frequency of Ca2.transients with an EC50valueof 2.3 μmol/*** the α1A-AR subtype with 5-methylurapidil （5-Mu） inhi-bited the stimulatory effect of phenylephrine with an IC50value of 6.7 nmol/***,blockade of the α1B-AR and α1D-AR subtypes with chloroethylclonidineand BMY 7378,respectively,did not affect the phenylephrine ***,thelocal Ca2.spark numbers were also increased by the activation of the α1-AR,andthis effect could be abolished selectively by *** importantly,A61603,anovel selective α1A-AR agonist,mimicked the effects of phenylephrine,but withmore potency (EC50value=6.9 nmol/L) in the potentiation of Ca2.transients,andblockade of the α1A-AR by 5-Mu caused abolishment of its ***:These results indicate that α1-adrenergic stimulation of intracellular Ca2.activityis mediated selectively by the α1A-AR.

关键词： α1-adrenergic receptor subtype cardiomyocyte Ca2. signaling A61603

The mineralization and transformation of both added organic nitrogen and native soil N in red soils from four different ecological conditions

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Nuclear Science and Techniques 1998年第3期 38-44页

作者： Ye Qing Fu 1, Zhang Qin Zheng 1, He Zhen Li 2. Xi Hai Fu 1, Wu Gang 1 and Wilson M J 3 ( 1Institute of Nuclear Agricultural Sciences, 2.0} of Soil Science and Agricultural chemistry, Zhejiang Agricultural {2., Hang

１ＩｎｔｒｏｄｕｃｔｉｏｎＯｒｇａｎｉｃｍａｔｅｒｉａｌｓｈａｖｅｂｅｎｅｆｉｃｉａｌｅｆｅｃｔｓｏｎｂｉｏｌｏｇｉｃａｌ，ｃｈｅｍｉｃａｌａｎｄｐｈｙｓｉｃａｌｐｒｏｐｅｒｔｉｅｓｏｆｓｏｉｌｓｉｎｔｈｅｔｒｏｐ... 详细信息

１ＩｎｔｒｏｄｕｃｔｉｏｎＯｒｇａｎｉｃｍａｔｅｒｉａｌｓｈａｖｅｂｅｎｅｆｉｃｉａｌｅｆｅｃｔｓｏｎｂｉｏｌｏｇｉｃａｌ，ｃｈｅｍｉｃａｌａｎｄｐｈｙｓｉｃａｌｐｒｏｐｅｒｔｉｅｓｏｆｓｏｉｌｓｉｎｔｈｅｔｒｏｐｉｃａｌａｎｄｓｕｂｔｒｏｐｉｃａ...

关键词： Agro ecosystems Microbial biomass Ryegrass Nitrogen transformations

Impact of Power Control Strategy and Cell Classification on Hierarchical Cellular System's Reverese Link

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The Journal of China Universities of Posts and Telecommunications 1999年第2期6卷 1-7页

作者： ZHOU Jie CHEN Jinu YOSHIKUNI Onozato(1. department of Computer Science, Chongqing Universities of Posts and Telecommunications. Chongqing. 400065. P R, China 2. department of Computer Science, Faculty of Engineering, Gunma {2.. Kiryu-City. Gunma P department of Computer Science Chongqing Universities of Posts and Telecommunications Chongqing 400065 P R. China department of Computer Science Faculty of Engineering Gunma University Kiryu-City Gunma Province Japan

This contribution deals with the outage probability in a hierarchical macrocell/microcell CDMA *** consider different attenuation models and imperfection of power control with log-normal *** on IS-95 protocol, the impacts of imperfect sectorization and imperfection of power control on outageProbability are fully investigated From the numerical results, we conclude that the high user capacity may beexpected in the case of relatively tight power control and narrower overlap betWeen sectors and the hierarchicalmacrocell/microcell cellular systems are potential for the future cellular mobile communication.

关键词： transmitter power control (TPC) binomial distribution log-normal dl'stribution hierarchicalcellular system outage probability cell classification: link capocity break point: perfect/imperfect powercontrol$$$$CLC number:##5TN 914.53

Synthesis of Nanometer-sized Mesoporous Oxide Spheres

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Chemical Research in Chinese Universities 2001年第2期17卷 143-147页

作者： LUO Qian, LI Li, XUE Zhi-yuan and ZHAO Dong-yuan (department of chemistry Analysis and Measurement Center, Fudan {2., Shanghai 2.0433, P. R. China) Fudan Univ Dept Chem Shanghai 200433 Peoples R China Fudan Univ Ctr Anal & Measurement Shanghai 200433 Peoples R China

A few hundreds nanometer-sized mesoporous silica and alumina spheres were synthesized in organic solvents. The impacts of ammonia, N, N-dimethylformamide (DMF) and stirring speed were also investigated.

关键词： Nanometer-sized Mesoporous Sphere Silica Alumina

Intelligent Iterated Local Search Methods for Solving Vehicle Routing Problem with Different Fleets

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Journal of Southwest Jiaotong university(English Edition) 2007年第4期15卷 344-352页

作者：李妍峰李军赵达 School of Economics and Management Southwest Jiaotong University Caotang School Sichuan Normal University Chengdu 610072 China

To solve vehicle routing problem with different fleets, two methodologies are developed. The first methodology adopts twophase strategy. In the first phase, the improved savings method is used to assign customers to appropriate vehicles. In the second phase, the iterated dynasearch algorithm is adopted to route each selected vehicle with the assigned customers. The iterated dynasearch algorithm combines dynasearch algorithm with iterated local search algorithm based on random kicks. The second methodplogy adopts the idea of cyclic transfer which is performed by using dynamic programming algorithm, and the iterated dynasearch algorithm is also embedded in it. The test results show that both methodologies generate better solutions than the traditional method, and the second methodology is superior to the first one.

关键词： Vehicle routing problem Savings method Iterated dynasearch algorithm Dynamic programming Iterated local search Random kick Cyclic transfer

Alkali metal atom adsorption on-top of the F_s^0 defective center of MgO(001) surface

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Journal of Shanghai university(English Edition) 2011年第3期15卷 223-228页

作者：张旭徐闰王林军洪峰 School of Materials Science and Engineering Shanghai University department of Physics College of Sciences Shanghai University

A plane wave density functional theory method was used to investigate the adsorption properties of isolated alkali metal atoms, including Li, Na, K, Rb and Cs on-top of the F 0 s defective center of MgO（001） surface. Among all the alkali metals, the lithium atom binds most strongly with the highest adsorption energy of 0.67 eV and the shortest distance of about 0.2.7 nm between metal and the surface, the binding energy for the sodium atom comes second, and just half of this value for the other alkali metal atoms. The relatively strong interaction of Li with the F 0 s center can be explained by a more covalent bonding involved, evidenced by results of both the projected density of states and the projected charge density. The bonding mechanism is discussed in detail.

关键词： alkali metal atom oxygen vacancy adsorption MgO density functional theory (DFT)

Biogenic nanostructured silica

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Progress in Natural Science:Materials International 2002年第6期 3-8页

作者： WANG Lijun, WANG Yunhua, LI Min, ZHANG Wenxu, ZHANG Fusuo and LI Tiejin(1. department of Resources, Environments & Agrochemistry, Huazhong Agricultural {2., Wuhan 430070, China 2. department of Plant Nutrition, China Agricultural {2., Beijing 100094, China 3. department of chemistry, Jilin {2., Changchun 13002., China) department of Resources，Environments & Agrochemistry，Huazhong Agricultural {2.，Wuhan 430070，China department of Plant Nutrition，China Agricultural university，Beijing 100094，China department of Resources，Environments & Agrochemistry，Huazhong Agricultural {2.，Wuhan 430070，China department of Plant Nutrition，China Agricultural university，Beijing 100094，China department of chemistry，Jilin {2.，Changchun 13002.，China

Silicon is by far the most abundant element in tbe earth crust and also is an essential element for higher plants, yet its biology and mechanisms in plant tolerance of biotic and abiotic stresses are poorly understood. Based on the molecular mechanisms of the biosilicification in marine organisms such as diatoms and sponges, the cell wall template-mediated self-assembly of nanostructured silica in marine organisms and higher plants as well as the related organic molecules are discussed. Understanding of the templating and structure-directed effects of silicon-processing organic molecules not only offers the clue for synthesizing silicon-based materials, but also helps to recognize the anomaly of silicon in plant biology.

关键词： biogenic silica nanostructures silica proteins biomineralization.