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Precipitation of Epsilon Copper in Ferrite Antibacterial Stainless Steel

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Journal of Materials Science & Technology 2008年第5期24卷 775-780页

作者： Zhixia ZHANG gang lin Zhou XU School of Material Science and Engineering Shanghai Jiao Tong University Shanghai 200030 China Technology Center Baoshan Iron ＆ Steel Co. Ltd. Shanghai 201900 China

The precipitation of epsilon copper at 1023 K ageing in ferrite antibacterial stainless steel was investigated by a combination of electron microscopy and micro-Vickers hardness measurement. The results show that epsilon copper precipitation occurs within 90 s, Complex multilayer structure confirmed as twins and stacking faults on {111}ε-Cu planes was observed in the precipitates. The precipitates grow by the lengthwise enlargement of a set of parallel layers, having [111]ε-Cu and [112]ε-Cu preferred growth orientations. The volume fraction of precipitates f formed within 120 min can be predicted by a modified Avrami equation （In1/1-f= kt ＋ b）. Simultaneously, substituent atom clusters with a size of 5-10 nm was found to occur in the solution and cause matrix strain. The precipitate morphology and distribution on the surface of ferrite antibacterial stainless steel are associated with surface crystallographic orientation of the matrix. The precipitates are predominantly located within the ferrite grains of 〈110〉 orientation. The precipitates located on {111}α-Fe surface planes have sphere or ellipse shape.

关键词： Stainless steel Epsilon copper precipitation Complex multilayer structure Electron microscopy Surface crystallographic orientation

Effects of Nitrogen Concentration on Microstructure and Antibacterial Property of Copper-Bearing Austenite Stainless Steels

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Journal of Materials Science & Technology 2008年第5期24卷 781-786页

作者： Zhixia ZHANG Laizhu JIANG gang lin Zhou XU School of Material Science and Engineering Shanghai Jiao Tong University Shanghai 200030 China[~echnology Center Baoshan Iron ＆ Steel Co. Ltd. Shanghai 201900 China Technology Center Baoshan Iron ＆ Steel Co. Ltd. Shanghai 201900 China

Austenite antibacterial stainless steels have been found to have wide applications in hospitals and food industries. In recent years epsilon copper precipitation in antibacterial stainless steels has obtained much research interest due to its antibacterial action. The objective of this study was to determine the effects of nitrogen concentration on the precipitation of epsilon copper and antibacterial property. Two kinds of austenite antibacterial stainless steels containing copper and different nitrogen concentration （0.02 and 0.08 wt pct, respectively） were prepared and the microstructures were characterized by a combination of electron microscopy and thermodynamic analysis. A mathematical expression was deduced to predict the effect of nitrogen concentration on the activity coefficient of copper, In（fCu/f^0cu）=0.53524＋4.11xN-0.48x^2N. Higher nitrogen was found to increase the free energy difference of copper concentration distribution between precipitation phase and austenite matrix, stimulate the aggregation of copper atoms from austenite, increase the precipitation amount and consequently enhance the antibacterial property of steel.

关键词： Austenite antibacterial stainless steels Epsilon copper precipitation Nitrogen concentration Thermodynamics analysis Antibacterial property

Simulation of proton–neutron collisions in inverse kinematics and its possible application

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Nuclear Science and Techniques 2021年第4期32卷 60-69页

作者： Bi-Lu Li gang-lin Yu Shi-Fei Shen Department of Engineering Physics Tsinghua UniversityBeijing 100084China

Neutrons have played a vital role in many nuclear physics *** some cases,the inverse kinematics of neutrons colliding with other nuclei are also worth *** this study,the inverse kinematics of thermal neutrons colliding with high-energy protons is simulated by using the Monte Carlo *** neutrons are taken as target particles,whereas protons are incident *** simulation implies that,after collision,the energy of the output neutron at 0°equals the energy of the incident proton.A possible application of the result is proposed that might yield single-energy *** key parameters of the conceptual design were evaluated,demonstrating that the design may reach high-neutron-energy resolution.

关键词： Inverse kinematics Mono-energetic neutron Proton Monte Carlo

Numerical Simulation of Flow in Centrifugal Pump with Complex Impeller

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Journal of Thermal Science 2011年第1期20卷 47-52页

作者： Bao-ling Cui Yong-gang lin Ying-zi Jin The Laboratory of Fluid Transmission and Application Zhejiang Sci-Tech University Hangzhou 310018China State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China

Based on the Navier-Stokes equations and the Spalart-Allmaras turbulence model,three dimensional turbulent flow fields in centrifugal pump with long-mid-short blade complex impeller are calculated and analyzed *** relative velocity and pressure distributions in the flowpart are *** is found that the flow in the passage of the complex impeller is unsymmetrical due to the joint action between volute and *** back-flow region is at inlet of long-blade suction side,near middle part of long-blade pressure side and outlet of short-blade suction *** flow near volute throat is affected greatly by *** relative velocity is large and it is easy to bring back flow at outlet of the complex impeller near volute *** static and total pressure rise uniformly from inlet to outlet in the *** impeller outlet,the pressure periodically decreases from pressure side to suction side,and then the static pressure sharply rise near the *** experimental results show that the back flow in the impeller has an important influence on the performance of pump.

关键词： Complex impeller Centrifugal pump Numerical simulation Experiment

Influences of Temperature and Coal Particle Size on the Flash Pyrolysis of Coal in a Fast-entrained Bed

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Chemical Research in Chinese Universities 2006年第1期22卷 103-110页

作者： CUI Li-jie lin Wei-gang YAO Jian-zhong Multi-phase Reaction Laboratory Institute of Process Engineering Chinese Academy of Sciences Bering 100080 P. R. China Graduate School Chinese Academy of Sciences Beijing 100080 P. R. China

The experiments on the flash pyrolysis of a lignite were carried out in a fast-entrained bed reactor as a basic study on a so-called ＇ coal topping process＇. The investigation focused on the effects of pyrolysis temperature and coal particle size on the product distribution and composition. The experimental results show that an increase in the pyrolysis temperature results in a higher yield of gaseous products while a larger particle size leads to a decrease of the liquid yield. An optimum temperature for the liquid yield was found to be 650℃. A certain amount of phenol groups was found in the liquid products, which may be used to produce high-valued fine chemicals. The FTIR analyses of the coal and chars show that aliphatic structures in the chars are gradually replaced by aromatic structures with the increasing of pyrolysis temperature and coal particle size. The results of this study provide fundamental data and optimal conditions to maximize light oils yields for the coal topping process.

关键词： Fluidized Bed Coal Flash pyrolysis Particle Size Temperature

Synthesis of Tetracycline Analogues and Test of Their Affinity on Synthetic Hydroxyapatite

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Chinese Chemical Letters 2002年第1期13卷 13-16页

作者： ling ling WENG gang lin Hu ZHENG School of Pharamacy West China University of Medical SciencesChengdu 610041

Eight of new 5-oxo-[1]benzopyrano[2,3-b]pyridines as the analogues of tetracycline, were designed and synthesized, and their affinity to the hydroxyapatite the inorganic composition of bone were tested.

关键词： Tetracycline affinity hydroxyapatite benzopyran-4-one.

Tidal current turbine based on hydraulic transmission system

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第7期12卷 511-518页

作者： Hong-wei LIU Wei LI Yong-gang lin Shun MA State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China

Tidal current turbines(TCTs) are newly developed electricity generating *** at the stabilization of the power output of TCTs,this paper introduces the hydraulic transmission technologies into *** hydrodynamics of the turbine was analyzed at first and its power output characteristics were predicted.A hydraulic power transmission system and a hydraulic pitch-controlled system were *** related simulations were ***,a TCT prototype was manufactured and tested in the *** test results have confirmed the correctness of the current design and availability of installation of the hydraulic system in TCTs.

关键词： Tidal current turbines(TCTs) Hydraulic power transmission Hydraulic pitch-controlled system Workshop test

A new method for the synthesis of N-substituted pyrroles

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Chinese Chemical Letters 2010年第11期21卷 1291-1294页

作者： Hai Xue Tao Ma lin Wang gang Liu Department of Synthetic Medicinal Chemistry Institute of Materia Medica Chinese Academy of Medical Sciences & Peking Union Medical College Beijing 100050 China

An unexpected reaction of 10-bromomethyl-12-oxocalanolide A（2） with primary amine was demonstrated and studied. Consequentially,a new method for the preparation of N-substituted pyrroles starting fromγ-halo-α,β-u... 详细信息

关键词： 12-Oxo-calanolide A Primary amine N-Substituted pyrroles Synthesis

Effect of soil set-up on the capacity of jacked concrete pipe piles in mixed soils

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第8期12卷 637-644页

作者： Jun-wei LIU Zhong-miao ZHANG Feng YU Cun-gang lin MOE Key Laboratory of Soft Soil and Geoenvironmental Engineering Institute of Geoteehnical Engineering Zhejiang University Hangzhou 310058 China

The increase in capacity of displacement piles with time after installation is typically known as soil/pile set-up. A full-scale field test is carried out to observe the set-up effect for open-ended concrete pipe piles jacked into mixed soils. Both the total capacity and the average unit shaft resistance increase approximately linearly with logarithmic time. The average increase rate for unit shaft resistance is 44% per log cycle, while the average increase for total capacity is approximately 21%. A review on case histories for long-term set-up indicates an average set-up rate of approximately 40%. Based on this, the mechanism of pile set-up is discussed in detail and a three-phase model is suggested.

关键词： Concrete pipe pile Jack piling Set-up Pile capacity