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precise Rates in the Law of the Iterated Logarithm under Dependence Assumptions

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Acta Mathematica Sinica,English Series 2008年第1期24卷 59-74页

作者： wel Dong LIU Zheng Yan LIN Department of Mathematics Zhejiang University Hangzhou 310027 P. R. China

Let {X, X1, X2,...} be a strictly stationaryφ-mixing sequence which satisfies EX = 0,EX^2（log2{X}）^2〈∞and φ（n）=O（1/log n）^Tfor some T〉*** Sn=∑k=1^nXk and an=O（√n/（log2n）^γ for some γ〉1/*** prove that limε→√2√ε^2-2∑n=3^∞1/np（｜Sn｜≥ε√ESn^2log2n＋an）=√*** results of Gut and Spataru （2000） are special cases of ours.

关键词： law of the iterated logarithm mixing sequences strong approximation

On the fracture resistance of adhesively jointing structures

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Journal of Zhejiang University-Science A(Applied physics & Engineering) 2006年第8期7卷 1289-1295页

作者： ZHOU Zhi-qiang YANG Qing-da CHEN wel-qlu Department of Civll Engineering. Zhejiang University Hangzhou 310027 China Rockweell Scientific Co. LLC 1049 Camino Dos Rios Thousand Oaks CA 91360 USA

The interface toughness of adhesively bonded structural members is one of the critical parameters for adhesive joint design. It is often assumed that the joint toughness is a material constant so that its value can be obtained from fracture tests of simple geometries such as DCB for Mode-Ⅰ, ENF for Mode-Ⅱ, using linear elastic fracture mechanics （LEFM）. However, the LEFM assumption of point-wise crack-tip fracture process is overly simplistic and may cause significant error in interpreting fracture test data. In this paper, the accuracy and applicability of various traditional beam-bending-theory based methods for fracture toughness evaluation, such as simple beam theory （SBT）, corrected beam theory （CBT） and experimental compliance method （ECM）, were assessed using the cohesive zone modelling （CZM） approach. It was demonstrated that the fracture process zone （FpZ） size has profound influence on toughness calculation and unfortunately, all the classic beam-bending theories based methods fail to include this important element and are erroneous especially when the ratio of crack length to FpZ size is relatively small （〈5.0）. It has also been demonstrated that after the FpZ size is incorporated into simple beam formulations, they provide much improved evaluation for fracture toughness. Formulation of first order estimate of FpZ size is aIso given in this paper.

关键词： Fracture mechanics Adhesive Cohesive zone model (CZM)

Growth of graphite film over the tops of vertical carbon nanotubes using Ni/Ti/Si substrate

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International Journal of Minerals,Metallurgy and Materials 2009年第1期16卷 128-134页

作者： Chia-chih Chuang wel-long Liu Wen-jauh Chen Jin-hua Huang photovoltaics Technology Center Industrial Technology Research Institute Hsinchu China Taibei Department of Materials Science and Engineering Formosa University Yunlin China Taibei Graduate School of Materials Science Yunlin University of Science and Technology Yunlin China Taibei

A substrate with Ni/Ti/Si structure was used to grow vertical carbon nanotubes （CNTs） with a graphite fihn over CNT tops by thermal chemical vapor deposition with CH4 gas as carbon source. The carbon nanotubes and the substrate were characterized by a field emission scanning electron microscope for the morphologies, a transmission electron microscope for the microstructures, a Raman spectrograph for the ctystallinity, and an Auger electron spectrometer for the depth distribution of elements. The result shows that when the thickness ratio of Ni layer to Ti layer in substrate is about 1, a graphite film with relatively good quality can be formed on the CNT tops.

关键词： carbon nanotubes (CNTs) graphite film CH4 gas thermal chemical vapor deposition (TCVD)

Intertextile Shanghai features a new trend concept show

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China Textile 2015年第8期 30-31页

作者： wel wel

Organised by Messe Frankfurt(HK)Ltd;the Sub-Council of Textile Industry,CCpIT;and the China Home Textile Association,Intertextile Shanghai Home Textiles-Autumn Edition will take place for the first time at the Nationa... 详细信息

关键词：上海法兰克福纺织行业家纺协会展览会委员会

Theoretical Studies on Substituent Effect of the Reaction of Amide and Formaldehyde

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Chemical Research in Chinese Universities 2010年第6期26卷 1007-1010页

作者： LAI wel-peng LIAN peng QIU Shao-jun GE Zhong-xue WANG Bo-zhou XUE Yong-qiang Xi ＇an Modern Chemistry Research Institute Xi ＇an 710065 P. R. China Applied Chemistry Department Taiyuan University of Technology Taiyuan 030024 P. R. China

The thermodynamic properties of the reaction of amide and formaldehyde were calculated via B3LYp method when substituents chosen included CH3,CH2CH3,CH2CH2CH3,CH2CH2CH2CH3,CH（CH3）2,CH2CH（CH3）2,CH（CH3）CH2CH3 and C（CH3）*** on the optimization of the structures for reactants and products,the thermodynamic functions of all the species for an actual state were *** thermodynamic data and the equilibrium constants were investigated within a temperature range of 300―343.15 *** calculated results show that the reaction is exothermic and *** trends of all thermodynamic properties are consistent with the *** preferential order of the substituent effect is CH2CH（CH3）2CH（CH3）CH2CH3CH2CH2CH2CH3 CH2CH2CH3CH2CH3≈CH（CH3）2C（CH3）3≈CH3.

关键词： 1 3 5-Trinitro-1 3 5-triazacyclohexane(RDX) Substituent effect Thermodynamics

Study on temperature property of band structures in one-dimensional photonic crystals

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Optoelectronics Letters 2007年第6期3卷 444-447页

作者： TONG Kai CUI wel-wei YAN Guo-hui Li Zhi-quan College of Electrical Engineering Yanshan University Qinhuangdao 066004 China Institute of Chemical Defense and Command Engineering Beijing 102205 China

Using transfer matrix method, the optical transmission properties in one-dimensional （l-D） photonic crystal is analyzed, When the temperature varies, not only the refractive index of the optical medium is changed because of the thermo-optical effect, but also the thickness of the optical medium is changed due to the thermal-expansion effect. Thus, the structure of 1/4 wave-plate stack in original photonic crystal is destroyed and the band structure varies. In this work, the effects of the temperature variation on the first and second band gap in a I-D photonic crystal are analyzed in detail. It is found that the changes of the starting wavelength, the cut-off wavelength and the forbidden band width depend linearly on the temperature.

关键词：晶体物理性质温度技术性能

Identifying the Geography and Determinants of O2O Online Retailers in Megacity in Central China:A Case Study of Zhengzhou City

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Chinese Geographical Science 2021年第5期31卷 931-950页

作者： QI Jinghui NIU Shuwen YE Chenxi WANG Luojia wel Yongna WEN Yuzhao ZHAO Shuling College of Civil Engineering and ArchitecturelCollaborative Imnovation Center for Aviation Economy Development Zhengzhou University of AeronauticsZhengzhou 450046China College of Earth and Environmental Sciences Lanzhou UniversityLanzhou 730000China School of Business Zhengzhou University of AeronauticsZhengzhou 450046China School of Economics Lanzhou University of Finance and EconomicsLanzhou 730101China College of Environment and planning Henan UniversityKaifeng 475004China College of Resource and Environment Henan University of Economics and LawZhengzhou 450046China

In recent years,O2O e-commerce,represented by online group-buying,has developed vigorously,which had significant impacts on urban commercial *** City is a rising national central city in China,and its e-commerce development level is ahead,but relevant researches are ***,the data of online retailers of *** was collected and combined with Baidu map and Baidu heat map ***,we adopted the methods such as spatial statistics and geodetector to explore the geography and determinants of O2O online retailers in Zhengzhou urban *** main conclusions are 1)The spatial development of O2O online retailers is characterized by significant global high-value agglomeration.2)The agglomeration areas of different types of O2O online retailers are *** of them are concentrated in the old urban area within the Third Ring Road of Zhengzhou City,forming five comprehensive agglomeration areas.3)The areas with the high e-commerce development level are mainly concentrated in the northeast and southwest of the x-shaped region formed by the intersection of Lianyungang-Lanzhou and Beijing-Guangzhou *** Square and Guomao 360 plaza are at the highest development level,followed by Zhongyuan Wanda plaza and Daxue Middle *** development level at other areas is relatively low.4)Zhengzhou’s O2O commercial pattern is highly dependent on physical *** population distribution,especially the population distribution during the nightlife period,plays a vital role in its spatial development,followed by *** influences of physical distance are slightly larger than that of time cost,but the difference between them is *** addition,travelling costs have the least *** paper could provide certain references for urban commercial planning.

关键词： O2O online retailers geodetector kernel density spatial development Zhengzhou City China

Reliability of Life Calculation Laws for Materials under Variable Amplitude Loading

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Open Journal of Applied Sciences 2022年第11期12卷 1922-1930页

作者： wel-Doret Djonglibet Tikri Bianzeube Kinet Ouinra Laboratory of Study and Research in Industrial Technology Faculty of Applied Sciences University of N’Djamena N’Djamena Chad Laboratory of Resistance of Materials and Mechanical Construction LRMCM Polytechnic University of Mongo N’Djamena Chad Laboratory of Building and public Works of the National School of public Works N’Djamena Chad

For many years, researchers have been looking for a reliable law that will take into account the type of loading, the mechanical characteristics of the material, the geometric configuration in the determination of the service life of mechanical parts. The service life of structures at risk (automotive, aeronautics, among others.) in service, subjected to variable solicitations in time, are random for a same type of loading. This article proposes to highlight the influence of this variation in service life on the reliability of structures by a probabilistic approach. The characteristics of the proposed law are satisfactory compared to the classical laws because it takes into account the parameters of the classical laws (Weibull law) and the dispersions of the lifetimes of a same material.

关键词： Design Reliability Durability Variable Loading

Human primary muscle stem cells regenerate injured urethral sphincter in athymic rats

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Animal Models and Experimental Medicine 2022年第5期5卷 453-460页

作者： Biniam M.Bekele Verena Schöwel-Wolf Janine Kieshauer Andreas Marg Andreas Busjahn Sarah Davis Gayle Nugent Anne-Karoline Ebert Simone Spuler Muscle Research Unit Experimental and Clinical Research Centera cooperation between the Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association and the CharitéUniversitätsmedizin BerlinBerlinGermany CharitéUniversitätsmedizin BerlinGermany Max-Delbrück-Center for Molecular Medicine in the Helmholtz Association BerlinGermany Berlin Institute of Health at CharitéUniversitätsmedizin BelrinGermany HealthTwist GmbH BerlinGermany Charles River Laboratories MattawanMichiganUSA Department of Urology and pediatric Urology University Hospital UlmUlmGermany

Background:The aim of the study was to demonstrate the efficacy of human muscle stem cells(MuSCs)isolated using innovative technology in restoring internal urinary sphincter function in a preclinical animal ***:Colonies of pure human MuSCs were obtained from muscle biopsy *** rats were subjected to internal urethral sphincter damage by *** days after injury,2×105 muscle stem cells or medium as control were injected into the area of sphincter damage(n=5 in each group).peak bladder pressure and rise in pressure were chosen as outcome *** repeatedly obtain the necessary pressure values,telemetry sensors had been implanted into the rat bladders 10 days prior to ***:There was a highly significant improvement in the ability to build up peak pressure as well as a pressure rise in animals that had received muscle stem cells as compared to control(p=0.007)3 weeks after the cells had been *** mini-mal histologic evidence of scarring was observed in treated ***:primary human muscle stem cells obtained using innovative technology functionally restore internal urethral sphincter function after *** into use in clinical settings is foreseeable.

关键词： human muscle stem cells sphincter injury telemetry urinary incontinence urodynamics