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991.
YANG Jia-long LI Ying WANG Fu ZANG Zheng-gui LI Si-jun 《钢铁研究学报(英文版)》2006,13(1):62-66
Several rigid substrates such as stainless steel, titanium alloy, aluminum alloy, nickel foil, silicon, and sodium lime glass have been employed for manufacturing high quality TiO2 films by metal organic chemical vapor deposition (MOCVD). The as-deposited TiO2 films have been characterized with SEM/EDX and XRD. The photocatalytic properties were investigated by decomposition of aqueous orange Ⅱ. UV VIS photospectrometer was employed to check the absorption characteristics and photocatalytic degradation activity. The results show that films synthesized on metal substrates display higher photoactivities than that on absolute substrates such as silicon and glass. It is found that solar light is an alternative to UV-light used for illumination during photodegradation of orange Ⅱ. TiO2 film on stainless steel substrate was regarded as the best one for photocatalysis. 相似文献
992.
大型船舶发电机短路故障分析与诊断方法探讨 总被引:1,自引:0,他引:1
文章深入地分析大型船舶发电机转子线圈匝间短路故障时的机械特征和电磁特性,发现转子匝间短路时励磁电流和无功功率的变化规律,提出分析和诊断匝间短路故障的方法. 相似文献
993.
中水用于电厂循环冷却水补充水的可行性分析 总被引:6,自引:0,他引:6
中水用于电厂循环冷却水补充水不仅可以扩大中水回用规模,而且也为电厂提供了一个水量充足的水源,为电厂生产用水提供保证。从火电厂循环冷却水系统的特点出发,结合电厂循环冷却水以及城市污水处理厂的二级出水情况,对中水用于火电厂循环冷却水补充水进行了理论分析、经济效益分析、工程实例分析,论述了其可行性,并为其应用提出了建议。 相似文献
994.
FU Xin XIE Haibo YANG Huayong JIA Zhijian & FANG Qun . State Key Laboratory of Fluid Power Transmission Control Zhejiang University Hangzhou China . Institute of Microanalytical Systems Zhejiang University Hangzhou China 《中国科学E辑(英文版)》2005,48(3):326-337
Micro fluidic analysis technology has been developed rapidly since the 1990s. The essentials of the technology are fabricating the micron structure (usually net channels, 20―100 μm wide and 10―30 μm deep) in chips by micro processing, and analyzing the fluids of samples or reagents chemically when they are controlled to flow and to be mixed in the micro structures. The occurrence of the technology makes the miniaturiza-tion, integration and portability of chemical detecting devices possibl… 相似文献
995.
ZHANGJinyong TANTianya FUZhengyi WANGWeimin 《武汉理工大学学报(材料科学英文版)》2005,20(2):83-85
In order to unclose the dynamics of SPS densification, a special sintering sample (Cul Ti wires compact) was designed. Characters of the shrinkage rates during sintering process and mierostructures of products fabrieated by the spark plasma sintering( SPS ) and hot-press .sintering were investigated. The experimental results reveal that a higher temperature field is formed at the connected area and conductive net of the compact. These high-temperature parts deformed more easily than other parts, which is believed to be the main cause of SPS fast densification, according to a hard-core and soft-hell material model. 相似文献
996.
The solution chemical and optical characteristics of formation of amine-terminated polyamidoamine dendrimer G2.0(NH2-PAMAM G2.0)-Au nanocomposites in the aqueous solution of NH2-PAMAM G2.0 at various mole ratios of Au(III) to NH2-PAMAM G2.0 were studied by both UV-visible spectrometry and fluorospectrometry. The NH2-PAMAM G2.0-Au nanocomposites, with a type of structure in which one Au nanoparticle is surrounded by several NH2-PAMAM G2.0 dendrimers, emit strong bluish violet fluorescence, and are uniform, water soluble and biocompatible as well as
very stable in frozen conditions. The size of gold nanoparticles in the nanocomposites is about 2.5 nm and decreases with
the increase of NH2-PAMAM G2.0 concentration. The NH2-PAMAM G2. 0 plays an important role in acting as host or micro-reactor for Au(III) before Au(III) reduction and acting as dispersant
and stabilizer for gold nanoparticles after Au(III) reduction. Preliminary experiments of cells staining to human embryonic
lung fibroblast cell lines show that the NH2-PAMAM G2.0-Au nanocomposites can be used as optical imaging markers for bioanalyses and medical diagnoses. 相似文献
997.
为消除冷坩埚连续成形钛合金铸棒表面缺陷,了解工艺参数对表面质量影响规律,并制备出无裂纹铸棒,通过正交试验和理论分析的方法,研究了不同工艺参数对表面质量的影响,研究表明:表面质量随功率和线圈匝数的增加而变坏,随抽拉速度和拉锭高度的增加先变好后变坏;各参数影响程度不同,线圈匝数影响最大,功率次之,抽拉速度再次,拉锭高度影响最小;铸造表面质量良好钛合金棒的工艺参数为:抽拉速度5mm/min,功率50kW,线圈3匝,拉锭高度30mm。 相似文献
998.
999.
The genetic algorithm (GA) is a general optimization technique that has some unique features that are especially suitable for structural engineering problems. This work uses a simple GA with elitism to find the optimum design of welded steel plate girder bridges. The objectives are to minimize the weight and the cost of the girders. Two types of plate-girder bridges are studied: a single-span bridge and a two-equal-span continuous bridge. Bridges with various span lengths, in increments of 20?ft, are investigated; results are tabulated, parametric studies are made, and meaningful conclusions are drawn. 相似文献
1000.
Phase transition of LaCrO3 and doped-LaCrO3 was studied by DSC, TG and XRD, and thermal expansion during the transition was analyzed. It is found that phase transition of LaCrO3 begins at about 240℃ and ends at about 265 ℃. Temperatures of phase transition rise obviously with increasing Ca^2+ content. The transition of LaCrO3 and Ca-doped LaCrO3 from orthorhombic to rhombohedral is accompanied with endothermic reaction. No obvious change occurs in mass, but remarkable shrinkage occurs during phase transition. 相似文献