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Fracture Characteristics of Fully Pearlitic Steel Wire in Tension and Torsion

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Journal of Iron and Steel Research International 2016年第11期23卷 1206-1212页

作者： Tian-zhang ZHAO guang-liang zhang Shi-hong zhang Ling-yun zhang Key Laboratory of Fundamental Science for National Defence of Aeronautical Digital Manufacturing Process Shenyang Aerospace University School of Mechanical Engineering Taizhou University Institute of Metal Research Chinese Academy of Sciences

The fracture characteristics of fully pearlitic steel wires with fine and randomly oriented lamellae have been investigated after tension and torsion, respectively. It is found that the predominant fracture mode under small pre- deformation is dimple. The analysis of the colony size and the lamellar structure near the fracture surface indicates that each dimple roots from one colony. A simulation of tensile deformation with several pearlitic colonies based on the real scanning electron microscopy （SEM） observation shows that the plastic deformation concentrates and the stress t^hxialit~＂ is larger ~it the boundaries bf colonies. It demonstrates the microe/＇a^ks initialize at colony boundaries. Thus, the colony size is a significant factor for fracture behaviors under small pre-deformation. On the other hand, the fracture surface is investigated after large pre-deformation via torsion. The results show that fracture characteristics vary with radius from dimples, elongated dimples to the fibrous structure. It indicates that the fracture charac-teristics are dependent on the pre-deformation. The fracture mode under large pre-deformation becomes an anisotropic fibrous structure instead of dimples.

关键词： fracture pearlitic steel wire tension torsion

Numerical Simulation of Flow Characteristics in Micro Shock Tubes

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Journal of Thermal Science 2015年第3期24卷 246-253页

作者： guang zhang Toshiaki Setoguchi Heuy Dong Kim Department of Mechanical Engineering Andong National University Department of Mechanical Engineering Saga University

Recently micro shock tubes have been widely used in many engineering and industrial fields, but the characteristics of unsteady flow are not well known to date in micro shock tubes. Compared to conventional shock tubes with macro scales, flows related to shock waves in micro shock tubes are highly complicated. Stronger viscous and dissipative interactions make shock wave dynamic behaviors significantly different from theoretical predictions. In the present study, a CFD work was applied to the unsteady compressible Navier-Stokes equations which were solved using a fully implicit finite volume scheme. The diaphragm pressure ratio and shock tube diameter were varied to investigate their effects on micro shock tube flows. Different wall boundary conditions were also performed to observe shock wave and contact surface propagation with no slip and slip walls. Detailed flow characteristics at the foot of shock wave and contact surface propagation were known from the present numerical simulations.

关键词： Micro shock tube Shock wave propagation Slip wall Unsteady flow CFD

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磷石膏固废资源化利用技术及应用前景

现代化工 2025年第1期45卷 34-41页

作者：桑安曹俊雅张莉昕毛文政张广积湖北三峡实验室湖北宜昌443008 中国矿业大学(北京)化学与环境工程学院北京100083 中国科学院过程工程研究所石油化工分子转化与反应工程全国重点实验室中国科学院绿色过程与工程重点实验室北京100190

介绍了磷石膏所含杂质及其对环境带来的危害,并阐述了磷石膏的几种预处理方法。依托VOS viewer可视化软件,对磷石膏资源化利用现状进行了分析,利用方向主要集中在农业、建筑材料、化工原料等方面。最后展望了未来磷石膏利用的技术创新方... 详细信息

介绍了磷石膏所含杂质及其对环境带来的危害,并阐述了磷石膏的几种预处理方法。依托VOS viewer可视化软件,对磷石膏资源化利用现状进行了分析,利用方向主要集中在农业、建筑材料、化工原料等方面。最后展望了未来磷石膏利用的技术创新方向,包括环境功能材料的制备和路基磷石膏基材料的开发等。

关键词：磷石膏堆存预处理资源化利用

Numerical analysis on transitions and symmetry-breaking in the wake of a flapping foil

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Acta Mechanica Sinica 2012年第6期28卷 1551-1556页

作者： Guo-Yi He Qi Wang Xing zhang Shu-guang zhang The School of Aircraft Engineering Nanchang Hangkong University LNM Institute of Mechanics Chinese Academy of Sciences The School of Transportation Science and Engineering Beihang University

Flying and marine animals often use flapping wings or tails to generate thrust. In this paper, we will use the simplest flapping model with a sinusoidal pitching mo- tion over a range of frequency and amplitude to investigate the mechanism of thrust generation. Previous work focuses on the Karman vortex street and the reversed Karman vor- tex street but the transition between two states remains un- known. The present numerical simulation provides a com- plete scenario of flow patterns from the Karman vortex street to reversed Karman vortex street via aligned vortices and the ultimate state is the deflected Karman vortex street, as the parameters of flapping motions change. The results are in agreement with the previous experiment. We make further discussion on the relationship of the observed states with drag and thrust coefficients and explore the mechanism of enhanced thrust generation using flapping motions.

关键词： Flapping motion. Immersed boundary method Wake. Symmetry-breaking

Electron-Phonon Interaction in Small Systems

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Chinese Physics Letters 1996年第12期13卷 919-922页

作者： WANG Zhong-he zhang Cun-zhou zhang guang-yin Deptatment of Physics Nankai UniversityTianjin 300071

The effects of electron-phonon interaction have to be taken into account for the physical process in a small system of condensed *** electron-phonon interaction in a I-D finite lattice system has been *** relation between the electron-phonon interaction and the symmetric properties of electronic states and phonons are considered,the transition probabilities are discussed.

关键词： phonon interaction system

Simultaneous Spectrophotometric Determination of Trace Palladium and Rhodium with2，4－TADAT

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Chemical Research in Chinese Universities 1994年第1期10卷 31-35页

作者： zhang, Xiao-ling zhang, guang

ＳｉｍｕｌｔａｎｅｏｕｓＳｐｅｃｔｒｏｐｈｏｔｏｍｅｔｒｉｃＤｅｔｅｒｍｉｎａｔｉｏｎｏｆＴｒａｃｅＰａｌｌａｄｉｕｍａｎｄＲｈｏｄｉｕｍｗｉｔｈ２，４－ＴＡＤＡＴＺＨＡＮＧＸｉａｏ－ｌｉｎｇ；ａｎｄＺＨＡＮＧＧｕａ... 详细信息

ＳｉｍｕｌｔａｎｅｏｕｓＳｐｅｃｔｒｏｐｈｏｔｏｍｅｔｒｉｃＤｅｔｅｒｍｉｎａｔｉｏｎｏｆＴｒａｃｅＰａｌｌａｄｉｕｍａｎｄＲｈｏｄｉｕｍｗｉｔｈ２，４－ＴＡＤＡＴＺＨＡＮＧＸｉａｏ－ｌｉｎｇ；ａｎｄＺＨＡＮＧＧｕａｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＣｈ...

关键词： Thiazolylazo diamino toluene Rhodium Palladium

Current research on electrospinning of silk fibroin and its blends with natural and synthetic biodegradable polymers

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Frontiers of Materials Science 2013年第2期7卷 129-142页

作者： Jian-guang zhang Xiu-Mei MO Biomaterials and Tissue Engineering Lab College of Chemistry Chemical Engineering & Biotechnology Donghua University Shanghai 201620 China

Silk fibroin （SF） is a kind of natural polymers with a great potential in biomedical application. Due to its good biocompatibility, biodegradability and minimal inflammatory reaction, SF is an excellent candidate for generating tissue engineering scaffolds. Electrospinning is a simple and effective method to fabricate nanofibers, which has several amazing characteristics such as very large surface area to volume ratio, flexibility in surface functionalities, and superior mechanical performance. The electro- spun nanofibers from SF and its blends have been used for varied tissue engineering. This paper will give a brief review about the structure, properties and applications of SF and blend nanofibers via electrospinning.

关键词： electrospinning nanofiber silk fibroin (SF) biodegradable polymer

Sensitivity of key factors and uncertainties in health risk assessment of benzene pollutant

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Journal of Environmental Sciences 2007年第10期19卷 1272-1280页

作者： LIU Zhi-quan zhang Ying-hua LI guang-he zhang Xu Department of Environmental Science and Engineering Tsinghua University Beijing 100084 China

Predicting long-term potential human health risks from contaminants in the multimedia environment requires the use of models. However, there is uncertainty associated with these predictions of many parameters which can be represented by ranges or probability distributions rather than single value. Based on a case study with information from an actual site contaminated with benzene, this study describes the application of MMSOILS model to predict health risk and distributions of those predictions generated using Monte Carlo techniques. A sensitivity analysis was performed to evaluate which of the random variables are most important in producing the predicted distributions of health risks. The sensitivity analysis shows that the predicted distributions can be accurately reproduced using a small subset of the random variables. The practical implication of this analysis is the ability to distinguish between important versus unimportant random variables in terms of their sensitivity to selected endpoints. This directly translates into a reduction in data collection and modeling effort. It was demonstrated that how correlation coefficient could be used to evaluate contributions to overall uncertainty from each parameter. The integrated uncertainty analysis shows that although drinking groundwater risk is similar with inhalation air risk, uncertainties of total risk come dominantly from drinking groundwater route. Most percent of the variance of total risk comes from four random variables.

关键词： Monte Carlo sensitivity uncertainty MMSOILS models risk assessment

Progress in Polymer-Ceramic Hybrid Antifouling Coatings

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Chinese Journal of Polymer Science 2023年第7期41卷 995-1001页

作者： Zhen-Qiang zhang Yin-Jie Huang Chun-Feng Ma guang-Zhao zhang Faculty of Materials Science and Engineering South China University of TechnologyGuangzhou510640China

Simultaneous realization of superior mechanical and antifouling properties is critical for a coating. The use of stereoscopic polysiloxanes in place of linear polysiloxanes to fabricate antifouling coatings can combine properties of organic and inorganic materials, i.e., they can exhibit both high hardness and wear resistance from inorganic components as well as the flexibility and tunability from organic components. This strategy is used to prepare hard yet flexible antifouling coatings or polymer-ceramic hybrid antifouling coatings. In this mini-review, we report the recent advances in this field. Particularly, the effects of stereoscopic polysiloxane structures on their mechanical and antifouling properties are discussed in detail.

关键词： Antifouling coating Organic-inorganic hybrid Sol-gel Hard yet flexible