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11.
12.
A new type of sample cell specially designed for micro-Raman spectra study on volatile melts is described.The cell is made of quartz.The lower section of the cell is circular ring-shaped and the one-end-closed hole in the cell is used for locating the heating body.The tube attached to the cell lid for placing the thermal couple is inserted into the sample,which ensures that the temperature measurement accuracy is good.The cell can be sealed for reducing the effect of the composition change caused by the inhomogeneous volatilization.During the Raman spectra scanning,the laser beam is transmitted into the cell through the side but not the top.Meanwhile,a furnace has been designed to match the cell.The heating body is closely coupled with the sample cell, and there is a hole on the side wall of the furnace for the entrance of the microlens.The assembly has performed well in the tested Raman spectrum measurement of molten NaNO3 at 602℃.  相似文献   
13.
傅里叶变换光谱仪中角反射体特性的研究   总被引:2,自引:1,他引:1  
本文分析了傅里叶变换光谱仪中用平面反射镜作为动镜时的晃动量问题,然后讨论了用角反射体作为动镜时对角反射体及其晃动量的要求,最后给出角反射体比平面反射镜具有更高分辨率的结论.  相似文献   
14.
An evolution compressible Stokes system is studied in a polygon. A lowest order corner singularity by the Laplacian operator is sorted out and an increased regularity is established in a suitable Banach space. In the lowest level, for each time the order of the corner singularity of the system is the same as that of the Laplacian. In addition, a singular function for pressure is defined and shows that the corner singularities originated from the corners of polygon may propagate along the directed streamlines.  相似文献   
15.
A variant of Taylor’s (1962) [23] scraper problem, in which, the lower plate rotates is considered. The non-linear partial differential equations governing the flow of a second grade fluid are modeled and solved by using the domain perturbation technique considering the angular velocity of the rotating plate as a small parameter. Also the rheology of the second grade fluid is examined by depicting the profiles of the velocity, stream function, pressure and stress fields.  相似文献   
16.
Borozan and Cornuéjols show that valid inequalities for an infinite relaxation for MIPs, relative to some vertex f of the linear relaxation, are determined by maximal lattice-free convex sets containing f. We show that cuts for the original MIP are given by such sets with f in the interior.  相似文献   
17.
微棱镜阵列型定向反射器特性   总被引:5,自引:1,他引:4  
袁景和  曾红军 《光子学报》1998,27(11):1023-1027
介绍了微棱镜阵列型定向反射器的材料折射率对入射孔径角的限制,定向反射率随入射角的变化关系,特别是提出了单元有效反射面积的计算方法,并进行了计算机模拟和实验,为该元件的设计和制作提供了理论依据。  相似文献   
18.
In this paper, compromise programming (CP) is viewed as the maximization of the decision maker’s additive utility function (whose arguments are the criteria under consideration) subject to an efficient frontier of criteria and the non-negativity constraints in a deterministic context. This is equivalent to minimizing the difference (‘distance’) between utility at the ideal point and utility at a frontier point on the criteria map, a meaningful statement as minimizing distances to the utopia is the ethos of compromise programming. By Taylor expansion of utility around the ideal point, the distance to the utopia becomes the weighted sum of linear and quadratic CP distances, which gives us the composite metric. While the linear terms pursue achievement, the quadratic ones pursue balanced (non-corner) solutions. Because some decision makers fear imbalance while others prefer large achievements even to the detriment of balance, the paper defines an aversion to imbalance ratio, so that the composite linear-quadratic metric should conform to this ratio depending on the decision maker’s preferences and attitudes. As the problem of selecting an appropriate metric is an ongoing issue in CP, the paper is a contribution to theory and practice. For the sole purpose of suggesting industrial applications, an example is developed.  相似文献   
19.
邱虹云  刘阳  孙利群  田芊 《光子学报》2007,36(9):1705-1709
通过实验定量研究了ICX412 CCD芯片在不同积分时间下的边角亮光的强度特征,并通过对CCD表面的拍摄,发现边角亮光的出现是由于CCD感光区域周边的两个辐射光源产生的近红外辐射.分析了黑场矫正方法对图像均方差(STD)影响,并研究了在积分过程中通过降低发光区域电路供电电压,再采用黑场矫正等手段消除了边角亮光对CCD长时间积分背景强度及STD的影响.  相似文献   
20.
The present paper is concerned with the existence of multiple solutions for semi-linear corner-degenerate elliptic equations with subcritical conditions. First, we introduce the corner type weighted p-Sobolev spaces and discuss the properties of continuous embedding, compactness and spectrum. Then, we prove the corner type Sobolev inequality and Poincaré inequality, which are important in the proof of the main result.  相似文献   
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