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Rare Metals 2010年第5期29卷 465-472页

作者： li jun yu Zhishui WANG Huiping li Manping School of Materials Engineering Shanghai University of Engineering Science Shanghai 201620 China

Titanium-based composite coatings reinforced by in situ synthesized TiB and TiC particles between titanium and B4C were successfully fabricated on Ti6Al4V by laser cladding. Phase constituents of the coatings were predicted by thermodynamic calculations in the Ti-BnC-Al and Ti-B-C-Al systems, respectively, and were validated well by X-ray diffraction （XRD） analysis results. Microstructural and metallographic analyses were made by scanning electron microscopy （SEM） and electron probe micro-analysis （EPMA）. The results show that the coatings are mainly composed of α-Ti cellular dendrites and the eutecticum in which a large number of needle-shaped TiB and a few equiaxial TiC particles are embedded. C is enriched in α-Ti cellular dendrites and far exceeds the theoretical maximum dissolubility, owing to the extension of saturation during laser cladding. The coatings have a good metallurgical bond with the substrate due to the existence of the dilution zone, in which a great amount of lamella β-Ti grains consisting of a thin needle-shaped martensitic microstructure are present and grow parallel to the heat flux direction; a few TiB and TiC reinforcements are observed at the boundaries of initial β-Ti grains.

关键词： composite coatings laser cladding in situ synthesis microstructure thermodynamic calculation

A Spectrometric Setup for Synchronous Total Internal Reflection Fluorescence Measurement at the Solid/liquid Interface

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Chinese Chemical Letters 2002年第6期13卷 571-572页

作者： Yao Qun li Jia Ju XU Run Tang WANG li jun yu Zhao li Department of Chemistry and the Key Laboratory of Analytical Sciences of MOE Xiamen UniversityXiamen 361005

A spectrometric setup to perform total internal reflection fluorescence (TIRF) and synchronous TIRF measurements at solid/liquid interfaces is presented. The combination of TIRF and synchronous fluorescence was proposed to analyze simultaneously different components at interfaces. The TIRF excitation, emission and synchronous spectra of a watersoluble porphyrin were obtained from water/glass interface using this setup without the existence of a surfactant.

关键词： Total internal reflection fluorescence synchronous fluorescence spectrofluorimeter meso-tetra(4-sulfonatophenyl)porphyrin.

The optimal time-frequency atom search based on a modified ant colony algorithm

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Optoelectronics Letters 2008年第3期4卷 227-230页

作者： GUO jun-feng li Yan-jun yu Rui-xing ZHANG Ke College of Astronautics Northwestern Polytechnical University Xi＇ an 710072China

this paper, a new optimal time-frequency atom search method based on a modified ant colony algorithm is proposed to improve the precision of the traditional methods. First, the discretization formula of finite length time-frequency atom is inferred at length. Second; a modified ant colony algorithm in continuous space is proposed. Finally, the optimal time- frequency atom search algorithm based on the modified ant colony algorithm is described in detail and the simulation experiment is carried on. The result indicates that the developed algorithm is valid and stable, and the precision of the method is higher than that of the traditional method.

关键词：最优化频率原子计算方法

Efficient Synthesis of Octalone

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Chemical Research in Chinese Universities 2007年第3期23卷 276-279页

作者： ZHANG Chen CHEN Jin-chun ZHENG Guo-jun li yu-lin State Key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou 730000 P. R. China

A highly efficient and convergent approach for the synthesis of octalone 1, the focal intermediate for the synthesis of several sesquiterpenoids, was developed based on the cationic cyclization strategy of the functio... 详细信息

关键词： Octalone (± )-1β,11-Dihydroxy-△^4-eudesmol Cationic cyclization Sesquiterpenoids Total synthesis

Analysis of S-SEED’s characteristics in optical switch

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The Journal of China Universities of Posts and Telecommunications 2008年第4期15卷 91-94页

作者： CAO Yong-sheng YIN Xiao-li XIN Xiang-jun yu Chong-xiu Key Laboratory of Optical Communication and lightwave Technologies Beijing University of Posts and Telecommunications Ministry of Education Beijing 100876 China

This article introduces the basic structure of a symmetric self-electrooptic effect device （S-SEED）, and applies the Kirchoff＇ s current law and a purely equivalent capacitive model, to analyze S-SEED＇s switch characteristics. linear approximation and N-segment approximation are utilized to obtain S-SEED＇s voltage-time （V-T） and characteristics. Theoretical analysis is verified by simulations, and the results demonstrate that the precision of S-SEED＇s switch time can satisfy the requirement in applications with linear approximation. Moreover, the simulations compare S-SEED＇s switch characteristics with different input powers and input contrast ratios, which reveal that increasing input contrast ratio is an effective way to improve S-SEED＇s switch characteristics.

关键词： symmetry S-SEED optical switch V-T characteristics characteristic simulations

Columnar to Equiaxed Transition During Solidification of Small Ingot by Using Electric Current Pulse

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Journal of Iron and Steel Research International 2009年第6期16卷 7-12页

作者： li Jie MA Jian-hong SONG Chang-jiang li Zhi-jun GAO yu-lai ZHAI Qi-jie Shanghai Key Laboratory of Modern Metallurgy and Materials Processing Shanghai University Shanghai 200072 China

A new approach to applying the electric current pulse （ECP） with parallel electrodes to the promotion of the transition from columnar crystal to equiaxed crystal and the improvement of macrosegregation was introduced. The ECP was applied to different stages of the solidification. The results showed that the application of the ECP in both the initial stage （the thickness of solidified shell reached 2 mm approximately） and the late stage （the thickness of solidified shell reached 14 mm approximately） of solidification can promote the columnar to equiaxed transition （CET）. The analysis showed that during solidification, a large number of nuclei around the upper surface fell off due to ECP, which subsequently showered on the melt and impinged the growth front of the columnar crystal. Therefore, the CEToccurred. In addition, this method was also employed to influence the solidification process of bearing steel, and the results showed that the structure was changed from columnar crystal to equiaxed crystal, indicating that ECP can enhance the homogeneity of structure and composition of bearing steel.

关键词： columnar to equiaxed transition solidification electric current pulse macrosegregation

P-glycoprotein regulating biphasic insulin secretion in rat pancreatic beta cells

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Chinese Medical Journal 2009年第21期122卷 2587-2592页

作者： TANG yun-zhao li Dai-qing SUN Fu-jun li li yu De-min Key Lab of Hormone and Development (Tianjin and Ministry of Health of the People's Republic of China) Institution of Endociinology Tianjin Metabolic Diseases Hospital Tianjin Medical University Tianjin 300070 China

Background A 65-kD mdrl （multi-drug resistance protein 1, P-glycoprotein）-Iike protein has been suggested to be the regulatory protein to the chloride channel protein 3 （CIC-3） mediating insulin granules acidification and release in mouse pancreatic beta cells. But the protein has not been deeply investigated. In this study, we identified existence of the 65-kda protein in rat islets and preliminarily explored its biological functions. Methods Total RNAs of rat kidneys served as positive controls, and pancreas, islets and INS-1 cells were extracted for reverse-transcript PCR （RT-PCR）, respectively. The cDNAs were run with specific primers selected from the mRNA of abcblb encoding P-glycoprotein. All PCR products were visualized in agarose gel electrophoresis and sequenced. Homogenates of rat islets and INS-1 cells were applied to SDS-PAGE. P-glycoprotein was detected by a specific monoclonal antibody, C219. Biphasic insulin release was measured in static incubations of rat islets with radioimmunology assay. Results Compared with positive control, expression of the P-glycoprotein mRNA segments were detected in the islets, INS-1 cells and pancreas. Sequence analysis confirmed that the PCR products were matched with mRNA of P-glycoprotein. A 65-kda protein was recognized by the antibody in the islets homogenate but not in that of INS-1 cells in Western-blotting. Instead, the homogenate of INS-1 cells contained a 160-kda protein recognized by the antibody. Insulin secretion of rat islets were stimulated by high glucose （16.7mmol/L）, and showed biphasic curve during 60-minute incubation. After co-incubation with cyclosporine A （CsA）, specific inhibitor to P-glycoprotein, the second phase of insulin secretion was reduced significantly while the first phase was not influenced. Conclusions The 65-kda protein expressed in rat islets is most likely a mini-P-glycoprotein. It may play a key role regulating biphasic insulin release.

关键词： pancreatic beta cell islet P-glycoprotein biphasic insulin secretion

Modeling of CHAMP satellite data according to the 3D surface spline model of geomagnetic fi elds

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Applied Geophysics 2020年第4期17卷 616-623页

作者： Yan Feng Huang Ya liu Shuang li yu-jun Jiang Yi The College of Mathematics and Statistics Nanjing University of Information Science&TechnologyNanjing 210044China State Key Laboratory of Lunar and Planetary Sciences(Macao University of Science and Technology) Macao 999078China State Key Laboratory of Space Weather Chinese Academy of SciencesBeijing 100190China

Surface observations and CHAMP measurement data are employed to develop a three-dimensional surface spline(3DSS)model of China's *** magnetic field distribution at the satellite level is then demonstrated using the model *** results of this model are compared and verifi ed by deriving the corresponding two(2DTY)and threedimensional(3DTY)Taylor polynomial *** such as the removal of disruptive geomagnetic fi elds,the data gap between the surface and satellite levels,and boundary eff ects are carefully considered during *** then focus on evaluating the modeling eff ect of the satellite *** satellite points not involved in the modeling procedure are selected,and the residuals,absolute change rates,and RMSEs of these points are *** show that the distribution of the magnetic fi eld determined by the 3DSS model is highly consistent with that obtained from the IGRF12 *** for component Y,the absolute change rates of other components are less than 0.5%.Specifi cally,the RMSE of Y of 3DSS is nearly 60%lower than those of 3DTY and 2DTY;the RMSE of other components of the former are also over 90%lower than those of the *** fi nding implies that the 3DSS model has good performance for modeling satellite data and its results are ***,the modeling eff ect of 3DTY is better than that of 2DTY.

关键词： geomagnetic field three-dimensional model surface Spline Chinese Meridian Project CHAMP satellite

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曲轴箱通风对GDI汽油机微粒排放的影响

内燃机学报 2016年第5期34卷 438-442页

作者：乔世杰李君刘宇吉林大学汽车仿真与控制国家重点实验室吉林长春130022

缸内直喷(GDI)汽油机微粒生成是由于雾化时间短及局部混合气过浓;同时,因为机油不可避免地参与燃烧也导致微粒排放增加.曲轴箱通风中未被油气分离器分离的机油蒸气占据机油消耗量比重较大,理论上这部分机油参与燃烧所产生的颗粒物对发... 详细信息

缸内直喷(GDI)汽油机微粒生成是由于雾化时间短及局部混合气过浓;同时,因为机油不可避免地参与燃烧也导致微粒排放增加.曲轴箱通风中未被油气分离器分离的机油蒸气占据机油消耗量比重较大,理论上这部分机油参与燃烧所产生的颗粒物对发动机最终的微粒排放影响也相应较大.因此,笔者在国产4G75缸内直喷汽油机上使用EEPS测定不同机油消耗条件下微粒排放特性,研究不同曲轴箱通风状态下未分离机油对GDI发动机微粒排放影响规律.结果表明:未被分离的机油消耗量增加导致微粒迅速升高,尤其在怠速工况下显著影响微粒生成质量;随发动机转速逐渐升高,机油消耗量对微粒生成的影响明显降低.

关键词：缸内直喷汽油机机油消耗量微粒质量浓度粒径分布

Pure spin polarized transport based on Rashba spin orbit interaction through the Aharonov Bohm interferometer embodied four-quantum-dot ring

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Chinese Physics B 2013年第4期22卷 420-428页

作者：吴丽君韩宇 School of Science Shenyang Ligong University Department of Physics Liaoning University

The spin-polarized linear conductance spectrum and current–voltage characteristics in a four-quantum-dot ring embodied into Aharonov–Bohm （AB） interferometer are investigated theoretically by considering a local Rashba spin–orbit interaction. It shows that the spin-polarized linear conductance and the corresponding spin polarization are each a function of magnetic flux phase at zero bias voltage with a period of 2π, and that Hubbard U cannot influence the electron transport properties in this case. When adjusting appropriately the structural parameter of inter-dot coupling and dot-lead coupling strength, the electronic spin polarization can reach a maximum value. Furthermore, by adjusting the bias voltages applied to the leads, the spin-up and spin-down currents move in opposite directions and pure spin current exists in the configuration space in appropriate situations. Based on the numerical results, such a model can be applied to the design of a spin filter device.

关键词： quantum dot ring Rashba spin–orbit interaction spin-polarized transport "bound states in the continuum" phenomena bias voltage Aharonov–Bohm interferometer