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841.
CHENZhi-hang CHENBo LUZhe-xue PANGDai-wen SONGYang MAHong-juan ZHOUXiang ZHANGXiao-lian WUXiao-jun DUYu-hao 《武汉大学学报:自然科学英文版》2005,10(3):587-590
A kind of zwitterionic water-soluble porphyrin 5-(N-trimethyl-4-aminiumphenyl)-10, 15, 20-tri (4-sulfonatephenyl) porphyrin trisammonium salt, has been synthesized. Its biological studies, interactions with DNA and bacteria cells, were investigated. The damage to the cell wall of bacteria E. coli were observed firstly by AFM (Atomic Force Microscope). 相似文献
842.
针对稳定土厂拌站采用的电子计量微机控制的方式,研究了基于“组态王”工控组态软件的监控系统的设计和实现,分析了稳定土厂拌站配料系统的特点,进而确定了系统的硬件架构;接着介绍了用“组态王”设计监控软件各主要功能模块的基本思想及涉及到的几个技术难点;最后研究了系统实现稳定配比控制的算法,该算法主要采用增量式控制和输出限幅的思想.现场测试实验证明,本系统真实再现了稳定土厂拌站的生产工艺流程,实现了配方/生产报表管理、故障报警等功能,并能对配料过程进行实时控制,保证产品达到一定的配比要求. 相似文献
843.
ZHANG Hongyu MA Ning WANG Zhiqiang 《科学通报(英文版)》2005,50(17):1864-1868
The effect of density of hydrogen-bonding donor (HBD) on the formation of layer-by-layer assemblies of poly(4-vinylpyridine) and poly(4-vinylphenol) was investigated. For this purpose, a series of ethyl-substituted poly(4-vinylphenol) (EsPVPhf) with variable ethyl substitute percentage was synthesized by grafting the phenol moiety along the poly(4-vinylphenol) backbone with 1-bromoethane. UV-vis spectroscopy revealed a uniform deposition process of the hydrogen-bonded multilayer consisting of poly(4- vinylpyridine) (PVPy) and EsPVPhf with variable density of HBD. Notably, it was found that increasing the HBD density of EsPVPhf resulted in a marked decrease of both amount of polymers adsorbed and film thickness, which should be related to the EsPVPhf conformation change from coiled state to extended conformation in ethanol solution. Compared with the effect of charge density in polyelectrolyte multUayer, however, there does not exist a critical density of HBD in our case of hydrogen-bonded multilayer assembly. In addition, surface structures of PVPy/EsPVPhf multilayer films also can be tailored controllably by adjusting HBD density of EsPVPhf. As a result, a new method for tuning the structure of hydrogen-bonding-directed multilayer films was developed. 相似文献
844.
MA Yutao LIN Yuan XIAO Xurui LI Xueping ZHOU Xiaowen 《科学通报(英文版)》2005,50(18):1985-1990
TiO2 nanotubes with diameters of 10 nm and lengths up to 600 nm were fabricated by directly using commercial TiO2 powders P25 as the precursors via sonication-hydrothermal combination approach. TiO2 nanotubes were characterized by means of X-ray powder diffractometer (XRD), scanning electron microscope (SEM), selected area electron diffraction pattern (SAED) and transmission elec- tron microscope (TEM). The light scattering property of film electrodes modified with TiO2 nanotubes was studied and revealed that TiO2 nanotubes can be used as the light scattering centers to increase the light absorption in dye-sensitized solar cells. The TiO2 nanotubes film electrodes mixed with 10% small nanoparticles TiO2 had both strong light scattering property and fine mechanical characteristics, and this kind of electrodes can be used as electrodes in improving the conversion efficiencies of dye-sensitized solar cells. 相似文献
845.
职称评定工作是高等学校的一项重要工作,它受到了教师的普遍关注,评定的合理与否,将直接影响到高校师资队伍的建设和发展.现针对高校教师职称评定问题,将层次分析法应用于模糊综合评价中,建立了多层次的模糊综合评价模型,给出了高校教师职称评定的量化方法,使职称评定工作尽可能地减少主观因素的影响. 相似文献
846.
在L光滑拓扑空间中给出了L光滑强不定映射、强不定开映射、强不定闭映射及L光滑强半连续映射、强半开闭映射,并讨论了它们的等价刻画和相互关系。 相似文献
847.
才让卓玛 《西北民族学院学报》2006,27(2):35-41
文章就汉藏英网络词典的研发、J2EE核心技术及数据库的设计,通过比较各种索引结构及查找算法,提出本系统的索引结构及算法,同时介绍了系统的主要功能. 相似文献
848.
ZHANG Haiyan XUWenzhong DAI Wentao HE Zhenyan MA Mi 《科学通报(英文版)》2006,51(4):409-416
METALLOTHIONEINS(MT)ARE LOW-MOLECULAR-WEIGHT AND CYSTEINE-RICH PROTEINS.THE FIRST MT PROTEIN WAS ISOLATED FROM EQUINE RENAL CORTEX IN1957[1].GENES EN-CODING MTS OCCUR IN DIVERSE ORGANISMS SUCH AS ANIMALS,HIGHER PLANTS,EUKARYOTIC MICROORGANISMS AND IN SOME… 相似文献
849.
WANG Chenghua MA Qingwen KONG Jiming CHEN Zefu LI Xiuzhen 《武汉大学学报:自然科学英文版》2006,11(4):787-792
According to the engineering investigation of long-distance oil and gas pipelines, the criterions and measures of route selection are drawn as follows: the flat landform is the first choice in route alignment. The foot of mountain is the first choice when the route passes by the valley. The route should pass by but the shady and deposited slope and not in sunny and erosive slope as possible as it can. The pipeline should be vertical to contour climbing and descending the mountain except steep slope. Tunnel can be used in crossing foothill. Perpendicularly traversing the river is better than beveling; the worst choice is to put the pipeline along the river. Bypass is the best choice in karsts area. The order of route selection should be pre-choosing, investigation, optimization and adjustment. 相似文献
850.
本文采用高效液相色谱法对国内外生产的各种蓝色圆珠笔油墨的种类进行了鉴别。采用ZORBAXBonus-RP柱,流动相为乙腈-水,检测波长为580nm,柱温25℃,本法简便,准确,灵敏度高,重复性好,可用于蓝色圆珠笔油墨种类的鉴定。 相似文献