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World journal of Gastroenterology 1999年第6期5卷 544-546页

作者： Wang h zheng Mh Zhang hB Zhu j he jR Lu AG ji YB Zhang Mj jiang Y Yu BM Li hW Shanghai Second Med Univ Ruijin Hosp Dept Surg Shanghai 200025 Peoples R China Shanghai Inst Digest Surg Shanghai 200025 Peoples R China

INTRODUCTIONPort-site recurrence after laparoscopic tumor surgery is a frequent complication in cancer operations, such as gallbladder, stomach, ovary and colon[1-5]. The incidence of port-site recurrence after laparoscopic colectomy ranged from 1.1% to 6.3%, in contrast to a 0.68% tumor wound recurrence rate in patients undergoing curative open colectomy[6-8]. The possible mechanisms proposed were: ① contaminated laparoscopic instruments passing in and out of the port frequently; ② increased exfoliated cancer cells from laparoscopic manipulation; ③ adhered tumor cells by pneumoperitoneum[9-12]. Some experiments reported that desufflation related to seeding of port wounds via a stable suspension of tumor cells in CO2 gas was an unlikely cause of port tumors, some supported a direct intraperitoneal seeding of exfoliated tumor cells as its etiology and the instruments passing in and out of the port may play an important role in local recurrence[13-15]. The colon tumor cells were more common since laparoscopic colectomy was wildly performed.

关键词： stomach neoplasms colonic neoplasms cell movement carbon dioxide pneumoperitoneum murine model

Photo-degradation of Acid-red 3B dye catalyzed by TiO_2 nanotubes

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journal of Environmental Sciences 2006年第4期18卷 783-787页

作者： jIANG Fang zheng Shou-rong zheng zheng XU Zhao-yi WANG Yan-jin State Key Laboratory of Pollution Control and Resource Reuse School of the Environment Nanjing University Nanjing 210093 China

TiO2 nanotube precursor was synthesized by the hydrothermal reaction of TiO2 powders with NaOh solution and the properties of the nanotube materials were tuned using different post-treatments. Transmission electron microscopic （TEM） observation revealed that the nanotube could be obtained by either a direct rinse with acid solution or rinse with distilled water followed by acid solution. The results of X-ray diffraction （XRD） and inductively coupled plasma （ICP） analysis indicated that the nanotube material was composed of h2Ti2O5·h2O. In addition, the photocatalytic activities of the resulting catalysts were found to be strongly dependent on the post-treatment. The results of the photocatalytic reaction showed that the degradation of Acid-red 3B dye fitted pseudo-zero-order kinetics and TiO2 nanotube prepared under direct rinse with acid solution exhibited a higher catalytic efficiency compared to other catalysts.

关键词： TiO2 nanotube Acid-red 3B photocatalysis hydrothermal reaction

Disruption of Cortical Microtubules by Overexpression of Green Fluorescent Protein-Tagged a-Tubulin 6 Causes a Marked Reduction in Cell Wall Synthesis

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journal of Integrative Plant Biology 2006年第1期48卷 85-98页

作者： David h. Burk Ruiqin Zhong W. herbert Morrison III zheng-hua Ye Department of Plant Biology University of Georgia Athens Georgia 30602 USA Richard B. Russell Agriculture Research Center U.S. Department of Agriculture Agricultural Research Service Athens Georgia 30604 USA

It has been known that the transverse orientation of cortical microtubules （MTs） along the elongation axis is essential for normal cell morphogenesis, but whether cortical MTs are essential for normal cell wall synthesis is still not clear. In the present study, we have investigated whether cortical MTs affect cell wall synthesis by direct alteration of the cortical MT organization in Arabidopsis thaliana. Disruption of the cortical MT organization by expression of an excess amount of green fluorescent protein-tagged a-tubulin 6 （GFP-TUA6） in transgenic Arabidopsis plants was found to cause a marked reduction in cell wall thickness and a de- crease in the cell wall sugars glucose and xylose. Concomitantly, the stem strength of the GFP-TUA6 overexpressors was markedly reduced compared with the wild type. In addition, expression of excess GFP- TUA6 results in an alteration in cell morphogenesis and a severe effect on plant growth and development. Together, these results suggest that the proper organization of cortical MTs is essential for the normal synthesis of plant cell walls.

关键词： Arabidopsis thaliana cell elongation cell wall synthesis cortical microtubules microtubule organization.

SILICON NITRIDE POWDER SYNThESIZED BY ThERMAL PLASMA METhOD

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中国有色金属学会会刊：英文版 1996年第3期6卷 103-107页

作者： Liang Shuquan huang Baiyun zheng Ziqiao(Central South University of Technology, Changsha 410083)Szepvolgyi j (Research Laboratory for inorganic Chemistry of hungarian Academy of Sciences,h-1502, Budapest, hungary) CENT S UNIV TEChNOL CHANGSHA 410083PEOPLES R CHINA hUNGARIAN ACAD SCI INORGAN CHEM RES LABH-1502 BUDAPESTHUNGARY

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关键词： Si3N4 nanosized powder thermal plasma method

Microstructure,magnetic properties of hexagonal barium ferrite powder based on calcination temperature and holding time

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Rare Metals 2021年第4期40卷 981-986页

作者： Si-Yun Shen hui zheng Peng zheng Qiong Wu jiang-Xia Deng Zhi-hua Ying Liang zheng Institute of Electron Device and Application Hangzhou Dianzi UniversityHangzhou 310018China Magnetism Key Laboratory of Zhejiang Province China Jiliang UniversityHangzhou 310018China

In this paper,single-phase and fine-grain hexagonal barium ferrite powder was prepared based on the optimal calcination *** influence of calcination conditions including temperature and holding time on microstructure and magnetic properties of powder were studied in ***,θ-2θ scan X-ray diffraction(XRD) results reveal that it is hard to obtain single phase of powder when the calcination temperature is lower than 850℃.In addition,the calcination time for single phase of barium ferrite powder was reduced with the increase in calcination *** electron microscopy(SEM) images and magnetic hysteresis loops show that the condition of low temperature and long holding time is beneficial for obtaining homogeneous size of grain and excellent magnetic ***,hexagonal barium ferrite powder with uniform grain size of~180 nm,high purity and excellent magnetic properties is obtained at optimal calcination condition of 850℃-10.0 h.

关键词： hexagonal barium ferrite Calcination Microstructure Magnetic

Two-component Brownian coagulation: Monte Carlo simulation and process characterization

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Particuology 2011年第4期9卷 414-423页

作者： haibo Zhao Chuguang zheng State Key Laboratory of Coal Combustion Huazhong University of Science and Technology Wuhan 430074 Hubei China

The compositional distribution within aggregates of a given size is essential to the functionality of com- posite aggregates that are usually enlarged by rapid Brownian coagulation, There is no analytical solution for the process of such two-component systems, Monte Carlo method is an effective numerical approach for two-component coagulation, In this paper, the differentially weighted Monte Carlo method is used to investigate two-component Brownian coagulation, respectively, in the continuum regime, the free-molecular regime and the transition regime. It is found that （1） for Brownian coagulation in the continuum regime and in the free-molecular regime, the mono-variate compositional distribution, i.e., the number density distribution function of one component amount （in the form of volume of the component in aggregates） satisfies self-preserving form the same as particle size distribution in mono-component Brownian coagulation; （2） however, for Brownian coagulation in the transition regime the mono-variate compositional distribution cannot reach self-similarity; and （3） the bivariate compositional distribution, i.e., the combined number density distribution function of two component amounts in the three regimes satisfies a semi self-preserving form. Moreover, other new features inherent to aggregative mixing are also demonstrated; e.g., the degree of mixing between components, which is largely controlled by the initial compositional mass fraction, improves as aggregate size increases.

关键词： Multivariate population balance Aggregation Stochastic method Mixing Self-preserving

Experimental and numerical simulation study on forced ventilation and dust removal of coal mine heading surface

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International journal of Coal Science & Technology 2024年第1期11卷 204-220页

作者： haotian zheng Bingyou jiang haoyu Wang Yuannan zheng Key Laboratory of Industrial Dust Prevention and Control&Occupational health and Safety Ministry of EducationAnhui University of Science and TechnologyHuainan232001China joint National-Local Engineering Research Centre for Safe and Precise Coal Mining Anhui University of Science and TechnologyHuainan232001China School of Safety Science and Engineering Anhui University of Science and TechnologyHuainan232001China

In order to study the problems of unreasonable airflow distribution and serious dust pollution in a heading surface,an experimental platform for forced ventilation and dust removal was built based on the similar *** the similar experiment and numerical simulation,the distribution of airflow field in the roadway and the spatial and temporal evolution of dust pollution under the conditions of forced ventilation were *** airflow field in the roadway can be divided into three zones:jet zone,vortex zone and reflux *** dust concentration gradually decreases from the head to the rear of the *** the forced ventilation conditions,there is a unilateral accumulation of dust,with higher dust concentrations away from the *** position of the equipment has an interception effect on the *** maximum error between the test value and the simulation result is 12.9%,which verifies the accuracy of the experimental *** research results can provide theoretical guidance for the application of dust removal technology in coal mine.

关键词： heading surface Forced ventilation Airflow field Dust pollution

Design and Control of a Pneumatically Actuated Transtibial Prosthesis

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journal of Bionic Engineering 2015年第2期12卷 217-226页

作者： hao zheng Xiangrong Shen Department of Mechanical Engineering University of Alabama 359 H.M. Comer Hall Box 870276 Tuscaloosa AL 35487-0276 USA

This paper presents the design and control of a pneumatically actuated transtibial prosthesis, which utilizes a pneumatic cylinder-type actuator to power the prosthetic ankle joint to support the user＇s locomotion. The pneumatic actuator has multiple advantages over the traditional electric motor, such as light weight, low cost, and high power-to-weight ratio. The objective of this work is to develop a compact and lightweight transtibial prosthesis, leveraging the multiple advantages provided by this highly competitive actuator. In this paper, the design details of the prosthesis are described, including the determination of performance specifications, the layout of the actuation mechanism, and the calculation of the torque capacity. Through the authors＇ design calculation, the prosthesis is able to provide sufficient range of motion and torque capacity to support the lo- comotion of a 75 Kg individual. The controller design is also described, including the underlying biomechanical analysis and the formulation of the finite-state impedance controller. The testing results of human subject indicate that the prosthesis is able to generate a natural walking gait and sufficient power output for its amputee user.

关键词： lower limb prosthesis powered prosthesis rehabilitation robotics assistive robotic devices

Ignition enhancement of ethylene/air by NO_x addition

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Chinese journal of Aeronautics 2013年第4期26卷 876-883页

作者： Guo Peng Chen zheng State Key Laboratory for Turbulence and Complex Systems College of Engineering Peking University

Recently, non-equilibrium plasma assisted combustion （PAC） has been found to be promising in reducing the ignition delay time in hypersonic propulsion system. NO x produced by non-equilibrium plasma can react with intermediates during the fuel oxidation process and thereby has influence on the combustion process. In this study, the effects of NO x addition on the ignition process of both the homogeneous ethylene/air mixtures and the non-premixed diffusion layer are examined numerically. The detailed chemistry for ethylene oxidization together with the NO x sub-mechanism is included in the simulation. Reaction path analysis and sensitivity analysis are conducted to give a mechanistic interpretation for the ignition enhancement by NO x addition. It is found that for both the homogenous and non-premixed ignition processes at normal and elevated pressures, NO 2 addition has little influence on the ignition delay time while NO addition can significantly promote the ignition process. The ignition enhancement is found to be caused by the promotion in hydroxyl radical production which quickly oxidizes ethylene. The promotion in hydroxyl radical production by NO addition is achieved in two ways：one is the direct production of Oh through the reaction hO2＋NO = NO2＋Oh, and the other is the indirect production of Oh through the reactions NO＋O2=NO2＋O and C2h4＋O = C2h3＋Oh. Moreover, it is found that similar to the homogeneous ignition process, the acceleration of the diffusion layer ignition is also controlled by the reaction hO2＋NO = NO2＋Oh.

关键词： Ethylene/air Ignition enhancement NO x addition Reaction path analysis Sensitivity analysis

INFLUENCE OF OPERATION UNDER EPIDURAL ANESThESIA ON PERIPhERAL T LYMPhOCYTE SUBSETS

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中华医学杂志(英文版) 1991年第3期104卷 194-197页

作者： j E Chen Z X zheng S h Wang Q h Chen Department of Anesthesiology Union Hospital Fujian Medical College Fuzhou.

This paper reports the variation of peripheral T lymphocyte subsets in patients before and after operation under epidural anesthesia using OKT monoclonal antibodies (McAb). The results show that Th and TS after anesthesia and during surgery were lower than before anesthesia and in normal controls (Phe ratio of Th/TS after anesthesia and during operation were lower than before anesthesia (Phere was no significant difference with normal controls (P>0.05). Therefore, we consider that the decrease in Th cells was one of the reasons for decrease in patient immune function during anesthesia and surgery. Five to seven days after surgery, patient Th cell levels tended to normalize. This showed that this abnormality was transient and reversible. The results also indicated that emphasising prevention of infection in post-operational case. should be done during the first 5-7 days after surgery.

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