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1. IntroductionThe transition metal silicides have attraeted much attention because of their potentialapplicatiOIl in very large scale integration (VLSI) de.ice[1]. Near-noble metal silicides canbe used as Schottky al1d ohn1ic col1tacts in silicon-based d…  相似文献   
2.
A simple theoretical model is presented for the reduction of a singly charged cation under conditions where migration is important and the cation is coupled to a neutral species through a chemical equilibrium, AB = A(+) + B(-). Only the steady-state transport-limited current, I(l), is considered. Simple algebraic equations describe the ratio of I(l) to the diffusion-limited current, I(d), as it depends on the degree of dissociation, determined by the ratio of equilibrium constant to formal concentration, K(AB)/C*(AB). The ratio I(l)/I(d) is found to depend on the ratio of electrolyte to equilibrium concentration of A(+) in bulk solution just as for the well-known result for the case without the equilibrium (i.e., K(AB) → ∞). The results are in accord with published experimental data for weak acids. Agreement and disagreement with other theoretical treatments of this problem are discussed. The main results are for 1:1 supporting electrolytes; extensions are made to 2:1, 1:2, and 2:2 supporting electrolytes.  相似文献   
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In breast cancer research, it is of great interest to identify genomic markers associated with prognosis. Multiple gene profiling studies have been conducted for such a purpose. Genomic markers identified from the analysis of single datasets often do not have satisfactory reproducibility. Among the multiple possible reasons, the most important one is the small sample sizes of individual studies. A cost-effective solution is to pool data from multiple comparable studies and conduct integrative analysis. In this study, we collect four breast cancer prognosis studies with gene expression measurements. We describe the relationship between prognosis and gene expressions using the accelerated failure time (AFT) models. We adopt a 2-norm group bridge penalization approach for marker identification. This integrative analysis approach can effectively identify markers with consistent effects across multiple datasets and naturally accommodate the heterogeneity among studies. Statistical and simulation studies demonstrate satisfactory performance of this approach. Breast cancer prognosis markers identified using this approach have sound biological implications and satisfactory prediction performance.  相似文献   
5.
A kind of composite buffering material was made by filling the voids of honeycomb paperboard with polyurethane. Drop tests were performed to evaluate the dynamic energy absorption capacity of the material. Based on the tests results, the mechanical behaviors of the material under low velocity dynamic impact conditions were analyzed. It was shown that the absorbed energy of the composite material varies inversely with the void diameter. The absorbed energy of the composite material is 1 - 2 times than that of honeycomb paperboard and polyurethane. The energy absorption efficiency of the composite material is better than those of honeycomb paperboard and polyurethane.  相似文献   
6.
刘文仓  谢建勋  宋娟  张晓文 《辐射防护》2003,23(1):42-48,54
本文介绍了对两种压水反应堆一回路模拟腐蚀氧化物(铁镍铬氧化物和铁镍氧化物)的溶解去污试验结果。选择的去污剂为0.3%草酸、0.1%柠檬酸和0.1%高锰酸钾。结果表明,实验温度为95℃、去污时间在6-48h范围内,0.3%草酸对铁镍铬氧化物和铁镍氧化物的溶解率分别为24.1%-65.3%和4.9%-64.4%;0.1%柠檬酸对二者的溶解率分别为2.2%-4.4%和0.37%-1.55%;0.1%高锰酸钾对二者几乎没有溶解作用。采用在草酸或柠檬酸去污前使用高锰酸钾去污剂的二步去污法,对两种氧化物的溶解度小于单独使用草酸或柠檬酸去污的一步法。  相似文献   
7.
<正>In the new round of global scientific and technological revolution and industrial transformation,one of the biggest bottlenecks we are facing is the lack of adequate materials technology.It is urgently hoped that there can be a major revolution in the materials research and development (R&D) field,rather than gradual and slow development[1].Under this background,materials genome engineering (MGE) has been developing rapidly,and its key technologies and engineering applications have ...  相似文献   
8.
Formationcrossectionsofnucleiwith(n,2n)reactionsChenXueShi,XieKuanZhong,ZhouShengMo,YanQingQuan(ShanghaiInstituteofNucle...  相似文献   
9.
Isolated graphene nanoribbons(GNRs)usually have energy gaps,which scale with their widths,owing to the lateral quantum confinement effect of GNRs.The absence of metallic GNRs limits their applications in device interconnects or being one-dimensional physics platform to research amazing properties based on metallicity.A recent study published in Science provided a novel method to produce metallic GNRs by inserting a symmetric superlattice into other semiconductive GNRs.This finding will broader the applications of GNRs both in nanoelectronics and fundamental science.  相似文献   
10.
Deep petroleum resources are stored under high temperature and pressure conditions, with the temperature having a significant influence on the properties of rocks. Deep in-situ temperature-preserved coring(ITP-coring) devices were developed to assess deep petroleum reserves accurately. Herein, hollow glass microspheres(HGMs)/silicone rubber(SR) composites that exhibit excellent thermal insulation properties were prepared as thermal insulation materials for deep ITP-coring devices. The mechanism ...  相似文献   
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