中国流行株HIV-1B/C重组亚型包膜蛋白真核表达载体的构建及稳定表达细胞株的筛选

目的获得高质量的中国流行株HIV-1B/C重组亚型包膜蛋白抗原。方法改造表达载体,以构建中国流行株HIV-1B/C重组亚型包膜蛋白基因带有筛选标记的真核细胞表达质粒,将所构建质粒转染真核细胞,用含有抗性的培养基筛选出能够高效、持续表达包膜蛋白的稳定表达细胞株。结果所构建的表达载体pVRPEnv转染细胞后可表达目的蛋白,并建立了稳定表达细胞系。结论获得了可以高效、持续稳定表达中国流行株HIV-1B/C重组亚型包膜蛋白的细胞株。     

酸增殖源及其在化学增幅抗蚀剂体系中的应用

介绍了酸增殖机理、酸增殖源的种类、典型化合物在化学增幅抗蚀剂体系中的应用及对灵敏度的提高 ,提出在计算机直接制版版材研究中的应用     

Selective CO oxidation in the presence of hydrogen over supported Pt catalysts promoted with transition metals

Selective CO oxidation in the presence of excess hydrogen was studied over supported Pt catalysts promoted with various transition metal compounds such as Cr, Mn, Fe, Co, Ni, Cu, Zn, and Zr. CO chemisorption, XRD, TPR, and TPO were conducted to characterize active catalysts. Among them, Pt-Ni/γ-Al₂O₃ showed high CO conversions over wide reaction temperatures. For supported Pt-Ni catalysts, Alumina was superior to TiO₂ and ZrO₂ as a support. The catalytic activity at low temperatures increased with increasing the molar ratio of Ni/Pt. This accompanied the TPR peak shift to lower temperatures. The optimum molar ratio between Ni and Pt was determined to be 5. This Pt-Ni/γ A1₂O₃ showed no decrease in CO conversion and CO₂ selectivity for the selective CO oxidation in the presence of 2 vol% H₂O and 20 vol% CO₂. The bimetallic phase of Pt-Ni seems to give rise to stable activity with high CO₂ selectivity in selective oxidation of CO in H₂-rich stream.     

Effect of the geometry and pattern of the flow channel on the performance of polymer electrolyte membrane fuel cell

This research focuses on the effect of the geometry and patterns of the gas flow channel on the PEM fuel cell performance. Simulation was conducted and the results were verified by experiments. Three-dimensional, single phase, compressible and isothermal models of 5 cm² electrodes, anode and cathode, were developed and studied by utilizing a commercial Computational Fluid Dynamics (CFD) software, FLUENT 4.5. Two types of gas flow channel were investigated: conventional and interdigitated. The results showed that the flow channel pattern does not have a significant effect on the anode cell performance, whereas it has a strong effect/influence on the cathode cell performance. The interdigitated design provides a higher limiting current density and cell performance than the conventional design on the cathode side. Moreover, the cell performance does not depend on the inlet and outlet channel widths. On the contrary, for the interdigitated design, it was influenced by the shoulder width. Finally, experiments were conducted to validate the simulation results.     

Energetic surface heterogeneity of nanocrystalline TiO<Subscript>2</Subscript> films for dye-sensitized solar cells

Dye sensitized solar cells (DSSCs) have been receiving significant attention because they have many advantages compared to conventional organic solar cells. It has been known that the photovoltaic characteristics of DSSC are highly dependent on the adsorption properties of dyes on TiO₂ films. To analyze the surface heterogeneity of TiO₂ surfaces, single-phase anatase nanocrystallite titanium films were prepared by sol-gel method using the hydrolysis reaction of titanium tetraisopropoxide under acidic condition and characterized by XRD, FE-SEM and BET analysis. The adsorption energy distribution functions were calculated by the generalized nonlinear regularization method. It was found that the shape and the intensity of the adsorption energy distribution curve determined were highly related with the physical properties (i.e., geometrical heterogeneity) and chemical characteristics (i.e., energetic heterogeneity) of nanocrystalline TiO₂ for DSSC.     

一种改进的细胞图像分割算法的研究

针对细胞图像的特点,提出一种改进的基于分水岭算法的细胞图像分割方法。在该方法中．对细胞图像进行数学形态学变换,即采用Top—hat变换后的图像与原始图像相加再减去Bottom—hat变换后的图像以得到最大对比度的图像．继而进行距离变换,最后运用分水岭算法进行分割。实验证明,该改进方法能够得到较好的分割结果。     

燃料电池发动机冷启动进气预热系统性能研究

为了分析冷启动过程中质子交换膜燃料电池发动机的空气加热系统的工作性能,采用ε-NTU方法和CFD仿真技术得到了双流程换热器内部的温度分布,研究了冷却液温度和流量对整体散热器的换热性能的影响。通过比较发现模拟值与测试数据的误差小于10%,表明仿真模型和采用多孔介质模型的研究方法的可行性。根据仿真结果,采用遗传算法得到了该系统采用的铝制散热器的冷却液的最优参数组合,研究结果为优化空气预热系统,提高散热器的冷却效率提供了指导。     

巧用CL-02DS中文设定显示单元

本文介绍了利用CL－02DS中文设定显示单元，配合程序设计，使之实现记录功能。     

光亮碱性Zn-Al合金电镀工艺研究

在碱性锌酸盐镀锌液中加入铝盐，研究成功了一种光亮碱性锌铝合金电镀工艺。采用霍尔槽试验探讨了镀液成分和工艺条件对镀层质量的影响，检测了镀液和镀层性能。研究结果表明：镀液阴极电流效率达到80%以上，镀液分散能力和复盖能力好，镀层中铝含量为1．5％左右，所形成的Zn-Al合金镀层结晶细致、光亮度好、结合力好、耐蚀性优良，适用于作高耐蚀性镀层。     

Media Niche of Electronic Communication Channels in Friendship: A Meta‐Analysis

The current landscape of communication technologies is characterized by a wide variety of choices. As each medium provides different affordances, each may occupy a different niche and be used in different relationships. Drawing on the theory of the niche, we did a meta‐analysis involving 27 effect sizes from 22 independent samples to test the correlation between media selection/use and friendship closeness. Results showed that the 5 communication channels filled 2 different friendship closeness niches. Mobile phone calls and texting had stronger positive correlations with friendship closeness than instant messaging, social network sites, and online gaming. Culture, but not gender, moderated some of these correlations: Friendship closeness had a stronger positive association with SNS use and online gaming in collectivist cultures.