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Insect Science 2011年第1期18卷 40-49页

作者： Meng Li jian liu Shu-sheng liu Ministry of Agriculture Key Laboratory of Molecular Biology of Crop Pathogens and Insects Institute of Insect Sciences Zhejiang UniversityHangzhou China

To better understand the etiology of begomovirus epidemics in regions under invasion we need to know how indigenous and invasive whitefly vectors respond to virus infection. We investigated both direct and indirect effects of infection with Tomato yellow leaf curl virus （TYLCV） on the performance of the invasive Q biotype and the indigenous Asian ZHJ2 biotype of whitefly Bemisia tabaci. The Q biotype performed better than the ZHJ2 biotype on either uninfected or virus-infected tomato plants. However, virus-infection of host plants did not, or only marginally affected, the performance of either biotype of whiteflies in terms of fecundity, longevity, survival, development and population increase. Likewise, association of the vectors with TYLCV did not affect fecundity and longevity of the Q or ZHJ2 biotypes on cotton, a non-host of TYLCV. These results indicate that the alien Q biotype whitefly, but not the indigenous ZHJ2 biotype, is likely to become the major vector of TYLCV in the field and facilitate virus epidemics.

关键词： Bemisia tabaci performance tomato Tomato yellow leaf curl virus virusinfection

Modeling study on the flow patterns of gas–liquid flow for fast decarburization during the RH process

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International Journal of Minerals,Metallurgy and Materials 2018年第2期25卷 153-163页

作者： Yi-hong Li Yan-ping Bao Rui Wang Li-feng Ma jian-sheng liu Collaborative Innovation Centre of Taiyuan Heavy Machinery Equipment and School of Materials Science and Engineering Taiyuan University of Science and Technology State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing School of Materials Science and Engineering North University of China

A water model and a high-speed video camera were utilized in the 300-t RH equipment to study the effect of steel flow patterns in a vacuum chamber on fast decarburization and a superior flow-pattern map was obtained during the practical RH process. There are three flow patterns with different bubbling characteristics and steel surface states in the vacuum chamber： boiling pattern（BP）, transition pattern（TP）, and wave pattern（WP）. The effect of the liquid-steel level and the residence time of the steel in the chamber on flow patterns and decarburization reaction were investigated, respectively. The liquid-steel level significantly affected the flow-pattern transition from BP to WP, and the residence time and reaction area were crucial to evaluate the whole decarburization process rather than the circulation flow rate and mixing time. A superior flow-pattern map during the practical RH process showed that the steel flow pattern changed from BP to TP quickly, and then remained as TP until the end of decarburization.

关键词： modeling study flow pattern vacuum chamber residence time decarburization RH process

Mathematical model of coupled thermo-mechanical behavior during plane strain compression of 06Cr19Ni9NbN steel

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Journal of Iron and Steel Research International 2018年第11期25卷 1179-1188页

作者： Yong-xing Jiao Yue Xu jian-sheng liu Jing-dan Li Xiu-zhi Zhang College of Materials Science and Engineering Taiyuan University of Science and Technology Taiyuan 030024ShanxiChina

The process of plane strain compression of 06Cr19Ni9NbN steel was carried out in the temperature range of 1000-1200℃ and the reduction ratio range of 10-50%.Combining the finite element numerical simulation,a new constitutive model of thermal deformation was established, which provides the theoretical basis to optimize the plarie strain compression process of the *** temperature and grain size at different regions were achieved by experiment and simulation,*** to the results,the mathematical models of stress and temperature during the plane strain compression were established by mathematical analysis *** new temperature models were established in three regions,respectively,and the stress models took account of the variation of temperature and'st^rain ***,by comparing the results of calculation,numerical simulation and experiment,the accuracy and validity of these mathematical models were verified.

关键词： Plane strain compression Coupled thermo-mechanical behavior 06Cr19Ni9NbN steel Numerical simulation Mathematical model

Stress release mechanism of deep bottom hole rock by ultra-high-pressure water jet slotting

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Petroleum Science 2023年第3期20卷 1828-1842页

作者： Hua-jian Wang Hua-Lin Liao Jun Wei jian-sheng liu Wen-Long Niu Yong-Wang liu Zhi-Chuan Guan Hedi Sllami John-Paul Latham School of Petroleum Engineering at China University of Petroleum East China QingdaoShandong266580China Key Laboratory of Unconventional oil and Gas Development Ministry of EducationQingdaoShandong266580China Shandong Ultra-deep Drilling Process Control Tech R&D Center QingdaoShandong266580China MINES Paris Tech PSLResearch Universty Geociences Rearch Centerbd Saint MicheParisFrance VAEL Euroe2 rue Johannes Keple 64000PauFrance Earth Science and Engineering Imperial College LondonLondonSW72AzUnited Kingdom

To solve the problems of rock strength increase caused by high in-situ stress,the stress release method with rock slot in the bottom hole by an ultra-high-pressure water jet is *** stress conditions of bottom hole rock,before and after slotting are analyzed and the stress release mechanism of slotting is *** results show that the stress release by slotting is due to the coupling of three factors:the relief of horizontal stress,the stress concentration zone distancing away from the cutting face,and the increase of pore pressure caused by rock mass expansion;The stress concentration increases the effective stress of rock along the radial distance from O.6R to 1R(R is the radius of the well),and the presence of groove completely releases the stress,it also allows the stress concentration zone to be pushed away from the cutting face,while significantly lowering the value of stresses in the area the drilling bit acting,the maximum stress release efficiency can reach 80%.The effect of slotting characteristics on release efficiency is obvious when the groove location is near the borehole *** the increase of groove depth,the stress release efficiency is significantly increased,and the release range of effective stress is enlarged along the axial ***,the stress release method and results of simulations in this paper have a guiding significance for best-improving rock-breaking efficiency and further understanding the technique.

关键词： Hard rock Slotting Stress release Down hole pressures Poroelastic mechanics Fluid-structure Interaction Ultra-high-pressure water jet

Prediction of critical forging penetration efficiency for 06Cr19Ni9NbN steel by dynamic recrystallization

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Journal of Iron and Steel Research International 2017年第6期24卷 649-653页

作者： Yong-xing Jiao jian-sheng liu Xing-wang Duan Xiao-hua Zheng Wen-wu He College of Materials Science and Engineering Taiyuan University of Science and Technology Taiyuan 030024 Shanxi China

In order to determine the critical forging penetration efficiency （FPE） of 06Crl9NigNbN steel, a new model was presented to describe critical FPE, which is significant to optimize the steel forging process. The plane strain compression tests were conducted to obtain the model and confirm its va- lidity. The results indicated that the dynamic recrystallization （DRX） volume fraction increases and the grain size decreases with the rise of reduction ratio. Meanwhile, the compression process was simulated by DEFORM software. The tensile tests were conducted and the results demonstrated that the mechanical properties gradually become stable when the reduction ratio increases to 30%, 34% and 40% at 1200, 1 100 and 1000 ℃, respectively. The calculated results based on this new model are consistent with experimental results, indicating that the model is suitable to predict the critical FPE for the steel.

关键词： Forging penetrationefficiencyDynamic recrystallizationMicrostructure evolutionMechanical property

MOLECULAR BEAM STUDIES ON ADSORPTION-DESORPTION KINETICS OF CO AND H_2 ON Ni SURFACE

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Chinese Chemical Letters 1993年第11期4卷 965-968页

作者： Guang Kang XI jian liu sheng Lin LI Tian Xi HE Department of Electron Science, Nankai University, Tianjin 300071

Adsorption-desorption kinetics of CO and H_2 on Ni surface were studied with molecular beam relaxation spectrometry. It is found that there are two adsorbed states in the substrate temperature range 330K 详细信息

关键词： MOLECULAR BEAM STUDIES ON ADSORPTION-DESORPTION KINETICS OF CO AND H2 ON Ni SURFACE high CO Ni

Catalytic properties of Cu-ZSM-5 in the trichloroethylene （TCE） combustion with air in fixed-bed system

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Journal of Environmental Science and Engineering 2009年第3期3卷 17-23页

作者： XU Cheng-hua liu Chuan-qi HAO Tian-wei YANG Wen liu jian-ying liu sheng-yu College of Resources and Environment Chengdu University of lnformation Technology Chengdu 610225 China

Cu-ZSM-5 molecular sieves were prepared by the ion-exchange of NH4-ZSM-5 with Cu^2＋ ions in Cu（NO3）2 solution, and was characterized by diffuse reflectance ultraviolet-visible spectroscopy （DRS-UV-vis）, fourier transform infrared spectroscopy （FT-IR） and X-ray powder diffraction （XRD） techniques. And at same time, the catalytic activity of the obtained Cu-ZSM-5 in the trichloroethylene （TCE） combustion with air in the fixed-bed system was also investigated in the present work. The results indicated that the copper content in Cu-ZSM-5 was increased with the increasing Cu2＋ concentration in ion-exchange solution, and however the catalytic activity was not always increased with the copper content in Cu-ZSM-5. It was found that Cu-ZSM-5, prepared with 0.091mol/L of Cu^2＋ solution, exhibited the best catalytic activity in TCE combustion. In combination with the characterization results by DRS-UV-vis and FT-IR techniques, it was deduced that the catalytic active species of Cu-ZSM-5 in TCE combustion with air was the skeletal copper of molecular sieves.

关键词： triehloroethylene (TCE) catalytic combustion ion-exchange Cu-ZSM-5 skeletal copper

基于挤压油膜理论的二维电液压力伺服阀稳定性分析

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中国机械工程 2017年第5期28卷 537-543页

作者：左希庆阮健孙坚李胜刘国文浙江工业大学特种装备制造与先进加工技术教育部重点实验室杭州310014 湖州职业技术学院机电与汽车学院湖州313000

针对飞机液压刹车系统,设计了一种2D电液压力伺服阀,以2D伺服螺旋机构为导阀,通过弹簧与主阀联动,采用直线位移传感器形成闭环位置反馈,精确控制出口压力;基于挤压油膜理论设计阀体结构,增大系统阻尼比,提高系统稳定性;在建立阀和油膜... 详细信息

针对飞机液压刹车系统,设计了一种2D电液压力伺服阀,以2D伺服螺旋机构为导阀,通过弹簧与主阀联动,采用直线位移传感器形成闭环位置反馈,精确控制出口压力;基于挤压油膜理论设计阀体结构,增大系统阻尼比,提高系统稳定性;在建立阀和油膜缓冲数学模型的基础上,仿真分析了主阀正开口量与弹簧变形量和主阀输出压力之间的关系,确保该阀具有良好的电流-压力特性;对初始系统、减小开环放大系数和增大系统阻尼比三种情况进行了稳定性仿真分析,验证了引入油膜阻尼缓冲设计的必要性。

关键词：挤压油膜压力伺服直线位移传感器阻尼比稳定性

Isolation and Complete Nucleotide Sequence of the Measles Virus IMB-1 Strain in China

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Virologica Sinica 2010年第6期25卷 381-389页

作者： Shao-hui MA Li-chun WANG jian-sheng liu Hai-jing SHI Long-ding liu Qi-han LI Institute of Medical Biology Chinese Academy of Medical Sciences and Peking Union Medical College Kunming 650118 China

The complete nucleotide sequence of the measles virus strain IMB-1,which was isolated in China,was *** in other measles viruses,its genome is 15,894 nucleotides in length and encodes six *** full-length nucleotide sequence of the IMB-1 isolate differed from vaccine strains (including wild-type Edmonston strain) by 4%-5% at the nucleotide sequence *** isolate has amino acid variations over the full genome,including in the hemagglutinin and fusion *** report is the first to describe the full-length genome of a genotype H1 strain and provide an overview of the diversity of genetic characteristics of a circulating measles virus.

关键词： Complete nucleotide sequence Genotype H1 Measles virus (MV)

Spatiotemporal dynamics of high-K^+-induced epileptiform discharges in hippocampal slice and the effects of valproate

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Neuroscience Bulletin 2013年第1期29卷 28-36页

作者： jian-sheng liu Jing-Bo Li Xin-Wei Gong Hai-Qing Gong Pu-Ming Zhang Pei-Ji Liang Qin-Chi Lu Department of Neurology Renji Hospital School of Medicine Shanghai Jiao Tong University Department of Biomedical Engineering Shanghai Jiao Tong University

The epileptic seizure is a dynamic process involving a rapid transition from normal activity to a state of hypersynchronous neuronal discharges. Here we investigated the network properties of epileptiform discharges in hippocampal slices in the presence of high K ＋ concentration （8.5 mmol/L） in the bath, and the effects of the anti-epileptic drug valproate （VPA） on epileptiform discharges, using a microelectrode array. We demonstrated that epileptiform discharges were predominantly initiated from the stratum pyramidale layer of CA3a-b and propagated bi-directionally to CA1 and CA3c. Disconnection of CA3 from CA1 abolished the discharges in CA1 without disrupting the initiation of discharges in CA3. Further pharmacological experiments showed that VPA at a clinically relevant concentration （100 μmol/L） suppressed the propagation speed but not the rate or duration of high-K＋-induced discharges. Our findings suggest that pacemakers exist in the CA3a-b region for the generation of epileptiform discharges in the hippocampus. VPA reduces the conduction of such discharges in the network by reducing the propagation speed.

关键词： epileptiform discharges hippocampal slices microelectrode array valproate