Si基热氧化Si_(1-x-y)Ge_xC_y薄膜的室温光致发光特性

采用等离子体增强化学气相淀积(PECVD)法在Si(100)衬底上淀积一层厚度约为170nm的富Ge高C含量的Si1-x-yGexCy薄膜,然后将其分别在800℃和1100℃下湿氧氧化20min.在室温下观测到强烈的光致发光.室温下的光致发光谱(PL谱)测量显示,800℃下氧化后的样品在370nm和396nm附近有两个光致发光带,1100℃下氧化后的样品只在396nm附近有一个光致发光带.396nm附近的发光带可归之于由氧化薄膜中的缺陷O-Si-O(Si02)或O-Ge-O(Ge02)引起的,而370nm附近的发光带与薄膜中Ge-C对发光中心有关     

全球频谱规划方案及频谱管理政策演进分析

本文基于对全球频谱规划方案的系统全面的分析,深入透彻的研究了全球频谱管理政策的演进方向,为中国移动频率的申请、频率的使用、频率规划的推动等工作提供了有力的支持,也为TD-SCDMA及其演进技术的发展起到推动作用。     

Migration of 2-butoxyethyl acetate from polycarbonate infant feeding bottles

An enforcement campaign was carried out to assess the migration of 2-butoxyethyl acetate (2-BEA) from polycarbonate infant feeding bottles intended for repeated use. Migration was measured by three successive migration tests into two of the European Union official food simulants: distilled water and 3% acetic acid testing at 40°C for 10 days. The Danish Veterinary and Food Administration (DVFA) has assessed that a migration above 0.33 mg for 2-BEA and a group of eight related substances kg^-1 foodstuff from plastics articles used exclusively for infants is unacceptable. Migration of 2-BEA was found from eight of 12 bottles. However, migration above the target value of 0.33 mg kg^-1 was not observed in the third decisive test from any of the 12 different brands of polycarbonate feeding bottles. A migration of between 0.05 and 0.26 mg kg^-1 from seven of 12 bottles was measured to 3% acetic acid in the third test, whereas no migration to distilled water was observed in the third test. The average recovery of 2-BEA after the 10-day exposure at the target value of 0.33 mg kg^-1 was 77% into distilled water and 36% into 3% acetic acid. The limited recovery was understandable as 2-BEA was partly hydrolysed in the aqueous food simulants and 2-butoxyethanol, a hydrolysis product and one of the related substances was identified. Quantification was carried out using gas chromatography after liquid/liquid extraction of the food simulant.     

Generating a nice triangular mesh on a regular parametric surface

In this paper, we present an iterative algorithm to generate a nice triangular curvilinear mesh on a regular parametric surface. The main idea is to obtain a reparametrization of the surface that behaves approximately like a conformal map in a finite number of points. These points are the vertices of a planar triangulation T ^op in the parameter space, which we would like to lift on the surface. The image of T ^op by means of the reparametrization provides us a triangular curvilinear mesh on the surface which reflects the properties of T ^op .     

IDEA算法中MA模块的研究

对分组密码加密算法IDEA中的MA模块进行分析,寻找其良好的性质,如其差分均匀度,线性复杂度等密码指标。通过软件编程证实MA的性质,进而在不同参数及结构下比较MA的性质,从中找寻MA模块的最优结构参数。     

屎肠球菌HY07产细菌素发酵条件的优化

对屎肠球菌HY07产细菌素的培养基组成和发酵条件进行了研究.通过单因素水平试验和正交试验,确定产细菌素的最佳培养条件为37℃培养24h,培养基初始pH为6.最佳培养基组成为:葡萄糖1％,鱼粉蛋白胨1.5％,牛肉膏1.5％,磷酸氢二钾0.2％,柠檬酸二铵0.2％,乙酸钠0.5％、硫酸锰0.025％,吐温-800.4％.在此条件下培养屎肠球菌HY07,所产细菌素抑菌圈可达12.60mm.     

在役球罐再次组焊冷裂纹敏感性研究

服役十年之后的07MnCrMoVR球罐需进行分拆搬迁,然后重新组焊.通过斜Y坡口对接裂纹试验和HAZ最高硬度试验对球罐材料再次组焊的冷裂纹敏感性进行研究,建议施工现场焊前预热温度不低于75℃.