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Random Attractors of Boussinesq Equations with Multiplicative Noise

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Acta Mathematica Sinica,English Series 2009年第3期25卷 481-490页

作者： yang rong li Bo ling GUO School of Mathematics and Statistics Southwest China University Chongqing 400715 P. R. China Center for Nonlinear Study Institute of Beijing Applied Physics and Computational Mathematics Beijing 100088 P. R. China

We study the random dynamical system （RDS） generated by the Benald flow problem with multiplicative noise and prove the existence of a compact random attractor for such RDS.

关键词： random dynamical systems random attractor Boussinesq equation white noise Wiener process

Preparation and characterization of the TiO_2-V_2O_5 photocatalyst with visible-light activity

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Rare Metals 2006年第6期25卷 636-642页

作者： liU Jianhua yang rong li Songmei School of Materials Science and Engineering Beihang University Beijing 100083 China

Visible-light responsive TiO2-V2O5 catalyst was prepared using a binary sol-gel and in-situ intercalation method. The TiO2 sol and V2O5 sol were mixed to disperse the V2O5 species in the TiO2 phase at molecular level. The binary sol was then intercalated into interspaces of polyaniline （PANI） by means of in-situ polymerization of aniline. Conglomeration of the TiO2-V2O5 dusters during the calcination process was avoided because of the wrap of polyaniline. The surface mor- phology, the crystal phases, the structure, and the absorption spectra of （PANI）,/TiO2-V2O5 and the composite catalyst were studied using SEM, XRD, FT-IR, and UV-Vis. The photoactivity of the prepared catalyst under UV and visible light irradiation were evaluated by decolorization of methylene blue （MB） solution. The results showed that the composite catalyst displayed a homogeneous anatase phase, and the vanadium pentoxide species was highly dispersed in the TiO2 phase. The composite catalyst responded to visible light because of the narrowed band gap. In this study, the catalyst with the sol volume ratio of TiO2： V2O5 = 10：1 presented the best photocatalytic activity.

关键词： inorganic non-metal materials visible-light active photocatalyst binary sol-gel synthesis composite catalyst

A note on self-normalized Dickey-Fuller test for unit root in autoregressive time series with GARCH errors

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Applied Mathematics(A Journal of Chinese Universities) 2008年第2期23卷 197-201页

作者： yang Xiao-rong ZHANG li-xin Dept. of Math. Zhejiang Univ. Hangzhou 310027 China

In this article, the unit root test for AR（p） model with GARCH errors is considered. The Dickey-Fuller test statistics are rewritten in the form of self-normalized sums, and the asymptotic distribution of the test s... 详细信息

关键词： unit root AR (p)-GARCH (1,1) self-normalized Dickey-Fuller test statistic.

Preparation and application of efficient TiO_2 /ACFs photocatalyst

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Journal of Environmental Sciences 2006年第5期18卷 979-982页

作者： liU Jian-hua yang rong li Song-mei School of Materials Science and Engineering Beihang University Beijing 100083 China

Activated carbon fibers （ACFs） supported titanium dioxide （TiO2） photocatalyst was developed by sol-gel method. The surface morphology and microstructure of the photocatalyst were characterized with scan electron microscope（SEM）, X-ray diffraction patterns and specific surface area analysis. The prepared photocatalyst is specially helpful for the removal of low molecular weight organic pollutants in wastewater. Decomposition efficiency of methylene blue solution by TiO2/ACFs catalyst reached almost 100% under 60 min reaction, while the decomposition efficiency by pure TiO2 was only 25% under 3 h reaction. The mineralization of toluene aqueous solution was measured by total organic carbon instrument, and the evolution of intermediate species was detected by gas chromatograph instrument. The results indicated that the prepared photocatalyst not only enhanced the photoactivity of TiO2, but also suppressed the emergence of intermediate species, which may be more deleterious to human. The enhancement of photocatalysis was due to increased efficiency of adsorption and desorption, which were control steps in heterogeneous photocatalysis.

关键词： titanium dioxide activated carbon fibers photocatalysis toluene methylene blue

Possible influence of sulfur content on magnetic aging behaviors of non-oriented electrical steels

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Frontiers of Materials Science 2013年第4期7卷 413-416页

作者： Wei-Min MAO Ping yang Chang-rong li Department of Materials State Key Laboratory of Advanced Metals and Materials University of Science and Technology Beijing Beijing 100083 China

Six non-oriented steel sheets of similar grade produced by different steel companies were used to analyze the magnetic aging behaviors after aging at 200~C for 48 h. It was observed that tiny S atoms, besides C and N, could also induce certain increase of core loss during aging. Thermodynamic calculation indicated that the nucleation driving force of FeS is much higher than those of Fe3C and Fe4N at low temperature, while S atoms, which tend to segregated around dislocations and boundaries, would diffuse rapidly along the crystalline defects while FeS particles would form. Therefore, higher content of tiny S atoms could increase core loss during service time of non-oriented steel sheets.

关键词： non-oriented electrical steel sulfur diffusion magnetic aging core loss

Telecloning Quantum States with Trapped Ions

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Communications in Theoretical Physics 2007年第5X期48卷 827-830页

作者： yang rong-Can li Hong-Cai liN Xiu HUANG Zhi-Ping School of Physics and OptoElectronics Technology Fujian Normal University Fuzhou 350007 China

We propose a scheme for telecloning quantum states with trapped ions. The scheme is based on a single ion interacting with a single laser pulse. In the protocol, an ion is firstly measured to determine whether the telecloning succeeds or not, and then another ion is detected to complete the whole procedure. The required experimental techniques are within the scope of what can be obtained in the ion-trap setup.

关键词： telecloning W states state-dependent trapped ions

Zinc Borohydride-Ionic liquid: Stable and Efficient System for Reductive Reaction of Aldehydes with Primary Amines to Corresponding Secondary Amines

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Chemical Research in Chinese Universities 2008年第1期24卷 120-122页

作者： NIAN Bao-yi XU Gang WU Jiang-ping yang li-rong Department of Chemistry and Biology Engineering Sanming University Sanming 365004 P. R. China College of Material Science and Chemical Engineering Zhejiang University Hangzhou 310027 P. R. China

Ionic liquids（ILs） are attracting much attention in various fields of chemical synthesis, electrochemical applications, liquid-liquid extractions, as well as biotransformations. Among those fields, the application of ILs as the potential green solvent for a wide variety of synthetic processes is an area of intense researches. High yield, high selectivity, and good catalytic charac-teristics have usually been achieved. After the isolation of products, ILs can usually be recovered and recycled many times by simple treating procedures, such as, filtration, extraction, and dryness.

关键词： Ionic liquid Zinc borohydride Reductive arnination BMImBF4

Analysis of Potential for HFC-23 Emission Reduction in China's Fluorine Chemical Industry

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Advances in Climate Change Research 2013年第4期4卷 260-266页

作者： liN Hui CUI Yong-li yang li-rong Foreign Economic Cooperation Ofce Ministry of Environmental Protection

China is one of the major producers of chlorodifluoromethane(HCFC-22)in the world.A large amount of fluoroform(HFC-23)is emitted during the production of *** factors of HFC-23 were calculated in accordance with the monitoring reports of eleven HFC-23 clean development mechanism(CDM)projects in China and the HFC-23emissions in 2000–2010 as well as that in 2011–2020 were estimated and projected,*** is expected that,by the end of 2020,emissions of HFC-23 in China will be as much as 230 Mt *** HCFC-22 producers voluntarily reduced HFC-23 emissions,it would contribute 3.2%–3.6%to the national CO2emission reduction target for 2020.

关键词： greenhouse gas HFC-23 potential for emission reduction

Relationship between resistin level in serum and acute coronary syndrome or stable angina pectoris

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2007年第12期8卷 875-880页

作者： QIAO Xiao-zhi yang Yun-mei XU Zhe-rong yang li-ai Department of Very Important Person the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China

Objective： To investigate the relationship between serum resistin level and acute coronary syndrome （ACS） or stable angina pectoris （SAP）. Methods： Sixty-five patients, with coronary artery disease, were enrolled and divided into three subgroups： acute myocardial infarction （AMI）, unstable angina pectoris （UAP） and SAP, and 26 healthy people were recruited as controls in the cross-sectional study. Serum resistin levels were determined by EliSA （enzyme-linked immunosorbent assay）, and WBC （white blood cell count）, hsCRP （high sensitive C-reaction protein）, CKmax （maximum of creatinkinase）, CK-MBmax （maximum of isozyme of creatinkinase） and cTnImax （maximum of troponin） were measured by standard laboratory methods. Results： The serum resistin levels were 4 folds higher in AMI patients, 2.43 folds in UAP patients and I. 12 folds in SAP patients than in the healthy controls （P〈0.05）. The resistin levels were also significantly different between AMI [（8.16±0.79） ng/ml], UAP [（5.59±0.75） ng/ml] and SAP [（3.45±0.56） ng/ml] groups （P〈0.01）; WBC, hsCRP, CK CK-MBmax and cTnlmax were significantly increased in AMI patients over UAP and SAP patients. Spearman analysis showed that serum resistin levels were positively correlated with WBC （r=0.412, P=0.046）, hsCRP （r=0.427,p=0.037）, CK CK-MBmax and cTnImax （r=0.731, 0.678, 0.656; P〈0.01）. Conclusion： Serum resistin levels increased with inflammatory factors and myocardial impairment. The results suggest that human resistin might play an important role in the pathogenesis of atherosclerosis and AMI as an inflammatory factor.

关键词： Resistin Acute coronary syndrome (ACS) Stable angina pectoris (SAP)