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N-K2Ti4O9/MIL-101 composites were successfully synthesized by a facile hydrothermal method, and were characterized by powder X-ray diffraction, UV–vis diffuse reflectance spectroscopy, the valence band X-ray photoelectron spectroscopy, field emission transmission electron microscopy, photoluminescence emission spectra, N2 adsorption–desorption and thermogravimetric analysis. Photocatalytic activities of N-K2Ti4O9, MIL-101 and the composites were investigated by the degradation of Rhodamine B (RhB) under visible light irradiation. The results show that the composites exhibit higher photocatalytic activity as compared with the pure materials. The synergistically enhanced photocatalytic activity of the composites is due to big adsorption capacity of MIL-101 and high separation efficiency of photogenerated electron-hole pairs through interfaces between N-K2Ti4O9 and MIL-101. 相似文献
3.
对现场生产的ZLl01合金铸件材质进行了全面分析,针对存在的产品成分不准,变质效果不好,力学性能不合格的问题,通过改进合金的锶变质工艺和热处理工艺,改善了合金的组织和性能,达到了对材料的成分、性能的各项要求。 相似文献
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在科学与工程计算中,在数千上万核上,模拟包含上亿网格单元的模型通常输出TB量级的时变数据集。这些数据集包含多个时刻的数据,每个时刻的数据分布存储在数千个文件,单时刻的数据量达到几GB甚至几十GB。为了并行地可视化这种时变数据集,本文设计了基于网格片的层次化数据结构,基于该数据结构改进和优化了并行可视化流程和数据通信算法。在集成到可视化软件后,实现了两个应用的模拟结果可视化。实测数据表明,对于单时刻5GB和32GB的数据,在数十上百个处理器核上,从数据读入到获得体绘制结果的时间分别为19秒和80秒,交互操作为2秒到10秒;三维面绘制在数秒钟内,切片分析在2秒以内。 相似文献
6.
NIU Jitai GUO Wei ZHANG Xinmei and LIU Xingqiu) State Key Laboratory of Advanced Welding Production Technology Harbin Institute of Technology Harbin China) State Key Laboratory of Metal Matrix Composite Shanghai Jiao Tong University Shanghai China 《稀有金属(英文版)》2003,22(4)
Through the vacuum diffusion welding SiCp/ZL101 aluminum with Cu interlayer,the effect of welding parame-ter and the thickness of Cu on the welded joint property was investigated,and the optimal welding parameters were putforward at the same time.The microstructure of joint was analyzed by means of optical-microscope,scanning electron mi-croscope in order to study the relationship between the macro-properties of joint and the microstructure.The results showthat diffusion welding with Cu interlayer could be used for welding aluminum matrix composites SiCp/ZL101 successfully. 相似文献
7.
设计了免疫荧光定量分析仪,用以对人体血液和尿液中的各种分析物(CRP、PCT、NTpro BNP、c Tn I等)含量进行快速准确的定量分析。光源采用大功率LED灯珠,采用窄带干涉滤光片对激发光和荧光进行滤光,采用内置运放的光电转换芯片OPT101进行荧光强度的检测。采用步进电机驱动,皮带传动方式带动双排滚珠宽体滑块在单根精密直线导轨上滑动,实现对检测样品的扫描式检测。通过与标准仪器进行对比试验,结果表明样机在小型化、快速性以及低成本的基础上,测量结果准确,测量精度高,稳定性好,能满足临床应用要求。 相似文献
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Chaidaroglou Antigoni; Kantrowitz Evan R. 《Protein engineering, design & selection : PEDS》1989,3(2):127-132
The function of aspartic acid residue 101 in the active siteof Escherichia coli alkaline phosphatase was investigated bysite-specific mutagenesis. A mutant version of alkaline phosphatasewas constructed with alanine in place of aspartic acid at position101. When kinetic measurements are carried out in the presenceof a phosphate acceptor, 1.0 M Tris, pH 8.0, both the kcat andthe Km, for the mutant enzyme increase by 2-fold, resultingin almost no change in the kcat/Km ratio. Under conditions ofno external phosphate acceptor and pH 8.0, both the kcat andthe Km for the mutant enzyme decrease by {small tilde}2-fold,again resulting in almost no change in the kcat/Km ratio. Thekcat for the hydrolysis of 4-methyl-umbelliferyl phosphate andp-nitrophenyl phosphate are nearly identical for both the wild-typeand mutant enzymes, as is the K1 for inorganic phosphate. Thereplacement of aspartic acid 101 by alanine does have a significanteffect on the activity of the enzyme as a function of pH, especiallyin the presence of a phosphate acceptor. At pH 9.4 the mutantenzyme exhibits 3-fold higher activity than the wild-type. Themutant enzyme also exhibits a substantial decrease in thermalstability: it is half inactivated by treatment at 49°C for15 min compared to 71°C for the wild-type enzyme. The datareported here suggest that this amino acid substitution altersthe rates of steps after the formation of the phospho-enzymeintermediate. Analysis of the X-ray structure of the wild-typeenzyme indicates that the increase in catalytic rate of themutant enzyme in the presence of a phosphate acceptor may bedue to an increase in accessibility of the active site nearSerl02. The increased catalytic rate of this mutant enzyme maybe utilized to improve diagnostic tests that require alkalinephosphatase, and the reduced heat stability of the mutant enzymemay make it useful in recombinant DNA techniques that requirethe ability to heat-inactivate the enzyme after use. 相似文献
9.
Stabilization of -alumina phase by silica was studied in nanocomposite (diphasic) alumina-silica gels by XRD and BET surface areas measurements. Five wt.% of silica (22 nm particles) increased the crystallization temperature of to -alumina by about 100°C from boehmite (10 nm particles) derived alumina. Stabilization of -alumina was caused by the formation of intimate contact (Al-O-Si) between components by diffusion of silica into the defect alumina structure.Also with the Department of Agronomy. 相似文献
10.
介绍了基于B/S模式的油库管理信息系统中Web动态报表的设计与实现。报表开发采用VS.NET环境中的客户端报表工具,与应用系统集成采用Reportviewer控件,通过合理的设置数据集参数与报表参数,对报表要显示的数据进行筛选,既实现了报表内容的动态显示,又减少了网络数据传输量,提升了系统性能,为Web动态报表的开发提供了参考方案。 相似文献