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Kouichi Tsuji Zoya Spolnik Kazuaki Wagatsuma Rik Nullens RenéE. Van Grieken 《Mikrochimica acta》2000,132(2-4):357-360
In conventional electron probe microanalysis (EPMA), the electron-induced X-rays are measured at large take-off angles of
about 45°. In the grazing exit EPMA (GE-EPMA) method, they are measured at small angles (< 1°). X-rays emitted from deep positions
can not be detected at grazing exit angles due to refraction effects at sample-vacuum interface; therefore, it is possible
to measure X-rays emitted only from near the surface with a low background. GE-EPMA is especially suitable for the analysis
of particles deposited on a flat sample carrier. The detection limits of GE-EPMA were investigated for artificial particles
(Al2O3, Fe2O3 and PbO2 , particle sizes: 1 ∼ 18 μm) deposited on flat sample carriers of Au thin films–Si wafers. The detection limits improved
with decreasing exit angle. The detection limits for characteristic X-rays at an exit angle of approximately 1.1° were 2–4
times lower than at 45°. A minimum detection limit of ca. 0.1% was obtained for Al in small particles. 相似文献
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We analyse a non-zero sum two-person game introduced by Teraoka and Yamada to model the strategic aspects of production development in manufacturing. In particular we investigate how sensitive their solution concept (Nash equilibrium) is to small variations in their assumptions. It is proved that a Nash equilibrium is unique if it exists and that a Nash equilibrium exists when the capital costs of the players are zero or when the players are equal in every respect. However, when the capital costs differ, in general a Nash equilibrium exists only when the players' capital costs are high compared to their profit rates. 相似文献
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本文使用5孔探针,在近失速工况下,对3种不同叶顶间隙时的后置蜗壳斜流叶轮进出口流场三维速度分布进行了测量,并将实验结果与非失速小流量的出口流场做了比较。 相似文献
67.
智能型高速CCD相机的时序电路的研制 总被引:3,自引:0,他引:3
首先详细地介绍了几种传统时序电路的实现方法与各自存在的优缺点 ,然后对 isp L SI器件的性能特点以及 TDI- CCD相机的组成结构、工作原理进行了简要地阐述 ,最后对采用 isp L SI器件实现 CCD相机时序电路的全过程进行了全面、细致地分析。本文结合实际课题 ,已由在线可编程大规模逻辑器件实现了高速 TDI- CCD相机的时序电路。此相机系统具有一些重要参数 (行周期、TDI级数、视频信号的增益、偏置参数 ) ,并可以灵活控制。同时该系统又具有高可靠性、高稳定性、低功耗等特点。 相似文献
68.
本文处理的是轴对称体大角度斜出水三元非线性问题,以出水角的余角α为小参数进行摄动展开,化为二维非线性问题求解.给出了零阶、一阶和二阶解的积分形式.其中零阶解对应于轴对称体垂直出水的情况,仍是非线性的.数值结果给出了不同Froude数、物体不同长细比情况下各阶自由面形状及各阶力的变化过程. 相似文献
69.
When a solid sphere exits water at a given velocity, the liquid column is pulled out of a liquid reservoir. The present study focuses on the dynamic deformation of the liquid column and on the identification of the liquid column regime on the Weber number and dimensionless time (We-t*) map. The three-dimensional model of water exit has been established on the basis of the lattice Boltzmann method. A mass tracking algorithm was incorporated to capture the free surface, where the liquid–gas two-phase flow is simplified to a single-phase free surface flow. The surface tension is included by adding a perturbation term and the gravity as a body force is introduced in form of calculating the equilibrium distribution with an altered velocity. The contact angle condition in numerical simulation is not considered. The accuracy of the numerical results is demonstrated through the comparisons with the prior numerical and the experimental results in the literature. A parametric study has been conducted numerically on the radius and volume and of liquid column. Besides, the relationship between the pinch-off time of a liquid column and the Froude number has been obtained. Moreover, the evolution of the liquid column shape with a wide range of the Weber number and time scales are discussed based on the number of ligaments and droplets. The liquid column exhibits different characteristics and has been divided into three regimes. The transition between different regimes has been analyzed and the critical Weber number is given. 相似文献
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