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41.
用正交光路全息干涉CT技术重建电弧等离子体三维温度场   总被引:3,自引:3,他引:0  
本文利用正交光路全息干涉技术和计算机有限角层析算法,借助电弧等离子体物理方程,对非对称电弧等离子体三维温度场的诊断进行了研究.  相似文献   
42.
Yiqing Gao  Xinmin Qi  Qi Jin 《Optik》2005,116(7):303-310
In this paper, digital mask technique is presented, and a high-quality projecting reduction lithography system has been set up successfully. The core device of digital mask technique is digital micromirror device (DMD) which belongs to one of the electrically addressed spatial light modulators. The output image of DMD can be equivalent to a gray-scale mask of high precision, which can control the exposure precisely. If it is combined with a high-quality projecting reduction system, the fabrication of submicron diffractive optical elements can be realized successfully. The overall design of the system is described in detail, and some diffractive optical element masks are fabricated. Experimental results verify that the system is feasible. In the end, system characteristics and system error are summarized.  相似文献   
43.
Natural rubber (NR)/rectorite nanocomposite was prepared by co-coagulating NR latex and rectorite aqueous suspension. The transmission electron microscopy (TEM) and X-ray diffraction (XRD) were employed to characterize the microstructure of the nanocomposite. The results showed that the nanocomposite exhibited a higher glass transition temperature, lower tan δ peak value and slightly broader glass transition region compared with pure NR. The gas barrier properties of the NR/rectorite nanocomposites were remarkably improved by the introduction of nanoscale rectorite because of the increased tortuosity of the diffusive path for a penetrant molecule. The nanocomposites have a unique stress-strain behavior due to the reinforcement and the hindrance of rectorite layers to the tensile crystallization of NR.  相似文献   
44.
本文从schiel方程推导出在给定冷却速度下铸铁枝晶奥氏体及共晶奥氏体中第三组元的偏析参数KS和偏析梯度KR的计算式,并讨论了计算值与实测值之间的差别。  相似文献   
45.
The gas pressure in a laser cavity of flowing chemical oxygen-iodine laser (COIL)is about 133.31333 Pa[1]. In this pressure range, effects of homogeneous and inhomo-geneous broadening competing with each other on the performances of a COIL are no-ticeable. Generally, a rate equation (RE) model is adopted to the performance modeling of a supersonic COIL, such as in refs. [1—4]. This model assumes the spectral line pro-file is homogeneously broadened. Homogeneous broadening assumption sim…  相似文献   
46.
[structure: see text] The viability of proteins as targets of thermally and photoactivated enediynes has been confirmed at the molecular level. Model studies using a labeled substrate confirmed the efficacy of atom transfer from diyl radicals produced from enediynes to form captodatively stabilized carbon centered aminoacyl radicals, which then undergo either fragmentation or dimerization. To exploit this finding, a family of enediynes was developed using an intramolecular coupling strategy. Derivatives were prepared and used to target specific proteins, showing good correlation between affinity and photoinduced protein degrading activity. The findings have potential applications in the design of artificial chemical proteases and add to our understanding of the mechanism of action of the clinically important enediyne antitumor antibiotics.  相似文献   
47.
Recently, Tang established a local asymptotic relation for the ruin probability in the Cramer-Lundberg risk model. In this short note we extend the corresponding result to the equilibrium renewal risk model.  相似文献   
48.
为满足强流加速器对准直器高散热性能、高抗辐射性能、超高真空、高定位精度、高稳定性和在线实时调整等特殊要求,在CSNS/RCS主准直器设计时针对结构方案和控制方案进行了详细设计和研究,针对关键部件:刮束器、真空盒、驱动装置和远程快速拆卸装置等设计难点进行了阐述,在设计中使用ANSYS完成了刮束器的热分析及支架强度和变形校核,用FLUKA程序对辐射屏蔽进行了分析和设计,确保主准直器设计的可靠性。  相似文献   
49.
Plasma Chemistry and Plasma Processing - A lamellar electrode structure is proposed to achieve the generation of a large-area plasma and the effective processing of the wool fabric with the...  相似文献   
50.
三联吡啶钌配合物和DNA相互作用已有大量报道,但基于类三联吡啶配体,如双吡啶吡咯,稳定的金属配合物和DNA作用却鲜见报道.利用荧光光谱、圆二色谱(CD)和紫外-可见光谱等表征手段,研究了4个已知的双吡啶吡咯钌配合物与DNA结合性质: [(PDP)Ru(COD)X],其中HPDP=2,5-bis(2’-pyridyl)pyrrolide,COD=1,5-环辛二烯,X=Cl- (1), NO3(-) (2);[(PDP)Ru(COD)(H2O)](BF4) (3) ; [(PDPCl)Ru(COD)Cl] (HPDPCl=2,5-bis(2’-pyridyl)-3,4-dichloropyrrolide(4).发现化合物1以经典嵌插方式和DNA结合,2和3可能为部分或非经典嵌插结合DNA,4主要以静电相互作用结合DNA.此外,通过MTT法考察了配合物1~4对人宫颈癌Hela细胞的体外细胞毒性.  相似文献   
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