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111.
在温度为389~1 245 ℃和砧面压力为1.0~5.0 GPa的条件下,利用金属高压熔融标定法,采用Cu、Al、Zn和Pb四种金属,对YJ-3000t型紧装式六面顶大腔体高温高压实验装置样品室内的实际压力进行了标定。通过对由四种金属所获得的标定结果的多项式三维模拟,获得了以叶蜡石为外传压介质、氧化铝为内传压介质的情况下,由砧面压力和样品室温度估算样品室内实际压力的定量表达式。该结果可为今后该设备上类似实验组装中样品腔内实际压力的估算提供方便准确的压力标。 相似文献
112.
Stress-induced leakage current characteristics of PMOS fabricated by a new multi-deposition multi-annealing technique with full gate last process 下载免费PDF全文
In the process of high-k films fabrication, a novel multi deposition multi annealing(MDMA) technique is introduced to replace simple post deposition annealing. The leakage current decreases with the increase of the post deposition annealing(PDA) times. The equivalent oxide thickness(EOT) decreases when the annealing time(s) change from 1 to 2. Furthermore,the characteristics of SILC(stress-induced leakage current) for an ultra-thin SiO_2/HfO_2 gate dielectric stack are studied systematically. The increase of the PDA time(s) from 1 to 2 can decrease the defect and defect generation rate in the HK layer. However, increasing the PDA times to 4 and 7 may introduce too much oxygen, therefore the type of oxygen vacancy changes. 相似文献
113.
R.J.D. Spurr M.J. Christi 《Journal of Quantitative Spectroscopy & Radiative Transfer》2007,103(3):431-446
In this paper we present a new linearization of the Radiant radiative transfer model. Radiant uses discrete ordinates for solving the radiative transfer equation in a multiply-scattering anisotropic medium with solar and thermal sources, but employs the adding method (interaction principle) for the stacking of reflection and transmission matrices in a multilayer atmosphere. For the linearization, we show that the entire radiation field is analytically differentiable with respect to any surface or atmospheric parameter for which we require Jacobians (derivatives of the radiance field). Derivatives of the discrete ordinate solutions are based on existing methods developed for the LIDORT radiative transfer models. Linearization of the interaction principle is completely new and constitutes the major theme of the paper. We discuss the application of the Radiant model and its linearization in the Level 2 algorithm for the retrieval of columns of carbon dioxide as the main target of the Orbiting Carbon Observatory (OCO) mission. 相似文献
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Hong-Shun Li 《Journal of Quantitative Spectroscopy & Radiative Transfer》2005,92(2):153-173
On the basis of the discrete ordinate scheme with (an) infinitely small weight(s), an easy-to-use and comprehensive method, named multi-rays method, is developed to calculate total, direct and medium intensities in arbitrarily specified directions. In doing this, for each of the specified directions, three identical discrete directions with infinitely small weights are employed to represent the three intensities. The new method is verified with two standard test problems, and is used to compute the intensities in two anisotropically scattering problems. 相似文献
116.
反演分析是现场监测⁃反演分析⁃工程实践检验⁃正演分析及预测的闭环系统的重要环节,而参数反分析是工程实践中研究最多的反分析问题.针对混凝土重力坝多参数反演分析是否具有唯一性,基于均质地基上重力坝在水压力作用下的位移解析解建立目标函数,进而以目标函数和非空凸集构建一个凸规划问题,然后通过分析目标函数的Hesse矩阵是否是正定矩阵,验证目标函数是否是严格凸函数,从而辨识构建的凸规划问题是否具有唯一全局极小点.对坝体和岩基弹性参数的不同组合方案分析表明,当采用理论值与实测值的差值的l1范数作为目标函数时,目标函数的Hesse矩阵均不能保证为正定矩阵,即混凝土重力坝多参数弹性位移反演分析凸规划问题不具有唯一全局极小点,反演分析不唯一. 相似文献
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Issa Sanni Jérôme Fortin Patrice Coorevits 《Journal of Computational and Applied Mathematics》2010,234(4):1161-1171
We present in this paper an improved non-smooth Discrete Element Method (DEM) in 3D based on the Non-Smooth Contact Dynamics (NSCD) method. We consider a three-dimensional collection of rigid particles (spheres) during the motion of which contacts can occur or break. The dry friction is modeled by Coulomb’s law which is typically non-associated. The non-associativity of the constitutive law poses numerical challenges. By adopting the use of the bi-potential concept in the framework of the NSCD DEM, a faster and more robust time stepping algorithm with only one predictor-corrector step where the contact and the friction are coupled can be devised. This contrasts with the classical method where contact and friction are treated separately leading to a time stepping algorithm that involves two predictor-corrector steps. The algorithm has been introduced in a 3D version of the NSCD DEM software MULTICOR. Numerical applications will show the robustness of the algorithm and the possibilities of the MULTICOR software for solving three-dimensional problems. 相似文献
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M. Schmidbauer P. Schäfer S. Besedin D. Grigoriev R. Köhler M. Hanke 《Journal of synchrotron radiation》2008,15(6):549-557
A new scattering technique in grazing‐incidence X‐ray diffraction geometry is described which enables three‐dimensional mapping of reciprocal space by a single rocking scan of the sample. This is achieved by using a two‐dimensional detector. The new set‐up is discussed in terms of angular resolution and dynamic range of scattered intensity. As an example the diffuse scattering from a strained multilayer of self‐assembled (In,Ga)As quantum dots grown on GaAs substrate is presented. 相似文献