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DEVELOPMENT OF COMPUTER SIMULATION SOFTWAREON PHASE TRANSFORMATION DURING QUENCHING

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Acta Metallurgica Sinica(English Letters) 2000年第2期13卷 618-622页

作者： L. chen, W. Xia and X. j. chen Department of Materials Science and Engineering, Nanchang Institute of Aeronautical Technology, Nanchang 330034, China

A computer software to simulate the phase transformation during quenching is designed based on Avrami equation and Scheil additivity principle of incubation period. The isothermal transformation diagrams of supercooled austenite are described by cubic spline functions. This software is possess of a good graphic interface of Windows style, can simulate the whole process in austenite decomposition during continuous cooling. If the cooling rate was given, the fraction of various microstructures transformed of austenite decomposition during continuous cooling at any temperature can be calculated. The simulation results are checked with the quenching experiment of 45 steel. The results indicate that the simulation results are comparatively close to the experimental results.

关键词： quenching phase transformation computer simulation software

Producing Renewable Biodiesel Fuel Using the Transesterification Process

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World j.urnal of Engineering and Technology 2015年第3期3卷 105-110页

作者： T. W. Chung Y. j. chen Department of Chemical Engineering Chung Yuan Christian University Taoyuan Taiwan

Biodiesel fuels are considered an alternative to fossil fuels. This is one of the effective means of transferring solar energy to dynamic energy via photosynthesis. It is also being considered in order to reduce the levels of carbon dioxide production worldwide. Biodiesel fuels are a renewable, biodegradable, and clean energy source. Producing enough biofuels to replace fossil fuels will bring the advantages of reduced air pollution and reduced other environmental impacts of fossil fuels. In this study, the response surface methodology (RSM) was used to design the experimental runs and to discuss the manufacturing variables on the transesterification of palm oil into fatty acid methyl ester (i.e. biodiesel fuel). The variation of the degree of effect for each variable in the transesterification process was observed. A second-order model was obtained to predict the yield of biodiesel fuel and the viscosity as a function of the reaction time, the mass fraction of catalyst in methanol and the molar ratio of methanol to plant oil. The experimental data of the yield and the viscosity of biodiesel fuels in different manufacturing variables are discussed in this study. Analysis of variance (ANOVA) was also applied to discuss the main factor and interaction factor effects of the manufacturing variables on the responses of the yield of unrefined biodiesel fuels. The shortage of farmland in Taiwan is a problem that needs to be solved before mass propagation of biofuels can be accomplished. In southeastern Asia, there are many farms and most energy farm products are cultivated (e.g. palm oil or j.tropha oil). In addition to sunflowers and soybeans in Taiwan, those energy farm products are possible choices for production of biodiesel fuel in Taiwan. The cooperation between Indonesia and Taiwan on the plantation of palm or j.tropha trees in Indonesia has conducted and will be one of the possible ways to solve the problem of the shortage of energy farm products in Taiwan.

关键词： Renewable Biodiesel Palm Oil Transesterification Response Surface Methodology (RSM)

T cell metabolism in graft-versus-host disease

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Blood Science 2020年第1期2卷 16-21页

作者： Yuj.ng Zou Benny j.chen Division of Hematologic Malignancies and Cellular Therapy/BMT Duke University Medical CenterDurhamNCUSA

Graft-versus-host disease(GVHD)is a maj.r source of morbidity and mortality following allogeneic hematopoietic stem cell transplant(allo-HSCT),one of the most effective approaches to treat hematopoietic malignancies.1 However,current prophylaxis regimens and treatments that reduce the detrimental effect of acute GVHD can be offset by increased incidence in opportunistic infections and relapse of the primary malignancy.2 In addition,the maj.rity of the approaches that inhibit T cell responses are non-specific,resulting in the inhibition of both alloreactive T cells and protective T cells from the ***,there is an increase in the demand to develop novel approaches that selectively target alloreactive T *** potential means to address this issue is to take advantage of the unique metabolic profile of activated T cells.

关键词： Graft-versus-host-disease Metabolism T cells

GREETINGS FROM CO-CHAIRS OF OECC'2003

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光学学报 2003年第S1期23卷 6-页

作者： Y. X. chen j. Q. Zhu j. Z. chen Prof.Sj.U ChinaProf.President of SIOM/CASProf.General Secretary of SCS

The purpose of the Optoelectronics and Communications Conference (OECC) is to provide opportunities for various engineers and researchers world-wide to interact, so contributing to progress in optical communication systems and the fields of optoelectronics. Workshops, tutorials and other relevant events will be offered at the mean time. We are very pleased to extend our sincerely thanks to all the participants of world-wide for your great contributions.

关键词： GREETINGS FROM CO-CHAIRS OF OECC’2003 will of on in be have

Packing Density Improvement through Addition of Limestone Fines, Superfine Cement and Condensed Silica Fume

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j.urnal of Materials Science and Chemical Engineering 2016年第7期4卷 29-36页

作者： j. j. chen A. K. H. Kwan P. L. Ng L. G. Li Foshan University Foshan China The University of Hong Kong Hong Kong China Vilnius Gediminas Technical University Vilnius Lithuania Guangdong University of Technology Guangzhou China

Adoption of a low water/powder (W/P) ratio is the key to improve the strength and durability of concrete, which relies on a high packing density because fresh concrete requires excess water to offer flowability. To obtain a high packing density, powders with different particle sizes, including limestone fines (LSF), superfine cement (SFC), condensed silica fume (CSF), were added to the cement paste and the resulting packing densities were measured directly by a newly-developed wet packing test. Results demonstrated that addition of powders with a finer size would more significantly improve the packing density but the powders should be at least as fine as 1/4 of the OPC to effectively improve the packing density. Packing density and voids ratio relationship showed that a small increase in packing density can significantly decrease the voids ratio, which could allow the W/P ratio to be reduced to improve the strength and durability of the concrete without compromising the flowability.

关键词： Condensed Silica Fume Limestone Fines Packing Density Superfine Cement Voids Ratio

Graphene-Semiconductor Quantum Well with Asymmetric Energy Gaps

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World j.urnal of Condensed Matter Physics 2013年第1期3卷 67-72页

作者： j. T. Wang D. S. Guo G. L Zhao j. C. chen Z. W. Sun A. Ignatiev Department of Physics Southern University and A & M College Baton Rouge USA Department of Physics University of Houston Houston USA Department of Physics Xiamen University Xiamen China Institute of Mechanics Chinese Academy of Sciences Beijing China

Semiconductor solar cell (PV cell) has been widely used for generating solar electricity. However, the high cost and severe pollution limits its application. Recently the discovery of graphene may open a door to fabricate a novel solar cell with lower cost and more environmentally friendly. Our proposed solar cell device consists of a graphene strip and two semiconductor strips with different energy gaps attached to the two edges of the graphene strip on a flat plane. This structure is a two-dimensional quantum well. The energy bands of graphene can be described by a two-dimensional Dirac equation centered on hexagonal corners (Dirac points) of the honeycomb lattice Brillouin zone. The 2 D Dirac equation has been solved numerically in this paper. The results indicate that the graphene quantum well possesses very dense quantum energy states which imply that quantum well of this type can absorb sun light with more different frequencies. If we use graphene quantum well to fabricate the photo voltaic cell, the efficiency of converting solar energy to electricity will be enhanced.

关键词： Graphene Quantum Well Dirac Equation PV Cell Energy Levels

COMPUTERIZED SIMULATION AND EXPERIMENTAL RESEARCH ON SOFT-SWITCHING ARC WELDING INVERTER POWER SOURCE

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Acta Metallurgica Sinica(English Letters) 2000年第1期13卷 128-132页

作者： S. j. chen S. Y. Yin L. Feng and L. Y. Li( 1) School of Materials Science and Engineering, Beij.ng Polytechnic University, Beij.ng 100022, China 2)National Key Laboratory of Advanced Welding Production Technology, HIT, Harbin 150001, China)

Based on the existing component models in the Pspice software package, a combined model for Insulat- ed the Bipolar Transistor (IGBT) is established, in which a non - linear is introduced to represent the parasitic capacitance. Using this model, computerized simulation is conducted for the FB - ZVZCS - PWM soft - ewitching converter,the switching and energy-transferring characteristics of the components are *** simulation results are testified by *** is proved that by abopting appropriate models,computerized simulation becomes an effective tool for investigation of arc welding inverter power source.

关键词： arc welding inverter,computerized simulation.IGBT soft switching

A Study on Uptake and Localization of Merocyanine 540 (MC540) in Murine Myeloid Leukemia Cells by Confocal Laser Scanning Microscopy (CLSM)

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Chinese j.urnal of Lasers 2000年第3期9卷 35-41页

作者： j. Y. chen-1 N. H. Cheung-2 S. C. chen-2, M. C. Fung-3 W. N. Leung-4 N. K. Mak- 4+ ( -1Department of Physics, Fudan University, Shanghai 200433, China -2Department of Physics, Hong Kong Baptist University, Hong Kong, China -3Department of Bi 复旦大学上海香港浸会大学香港香港大学香港

The intracellular localization of merocyanine 540 (MC540), a photosensitizer commonly used in the photo-inactivation of leukemia cells, was studied using confocal laser scanning microscopy. It was found for the first time that MC540 not only localized in the plasma membrane but also in the cytoplasm and the nuclear membrane of the murine myeloid leukemia M1 and WEHI 3B (j.S) cells. Exposure of MC540 treated leukemia cells to light under conditions that could cause photobleaching did not cause the redistribution of cell-bound MC540. Rapid localization of MC540 in the cytoplasm was observed 5 minutes after exposure of leukemia cell to MC540, indicating that MC540 could promptly be internalized by these two leukemia cell lines. In contrast, localization of MC540 was limited only to the plasma membrane of erythrocytes. These results suggest that the binding pattern of MC540 is cell type dependent and may be related to the efficacy of photosenitization in photodynamic therapy.

关键词： merocyanine 540 Confocal Laser Scanning Microscopy Myeloid Leukemia cell

Termination of polymorphic ventricular tachycardia storm by catheter ablation in a patient with cardiomyopathy induced by incessant idiopathic left ventricular tachycardia

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南京医科大学学报（自然科学版） 2007年第10期27卷 1105-1105页

作者： Shan, Q. j. chen, M. L. Xu, D. X. Zou, j. G. Yang, B. chen, C. Cao, K. j. Nanj.ng Med Univ Affiliated Hosp 1 Dept Cardiol Nanjing 210029 Peoples R China.