硼对金属间化合物Ni_3Fe氢气诱发环境氢脆的影响(英文)

In this paper the tensile properties of both ordered and disordered Ni-24Fe and Ni-24Fe-0.03%B(wt%)alloys in gaseous hydrogen was investigated.The result shows that the ductility of the disordered Ni_3Fe is significantly larger than that of ordered material in gaseous hydrogen.However,the ductility of ordered Ni3Fe doped with 0.03%B is nearly the same as that of disordered one indicating the obvious suppressing effect of boron on the H_2-induced embrittlement.Based on the segregation behavior of boron in Ni_3Al,it is proposed that the suppressing effect of boron in Ni_3Fe on the H_2-induced embrittlement is attributed to the segregation of boron on grain boundaries,thereby reducing the hydrogen diffusivity along the grain boundaries.     

中国学生贷款补贴的资助功能与绩效评价

目前我国的国家助学贷款有贴息、代偿、风险补偿金、税收优惠等四种补贴形式。在利率市场化条件下,贴息、代偿等直接补贴和风险补偿金、税收优惠等间接补贴都可以扩大资助面,减轻还贷负担,且绩效水平相同;而在现实条件下,由于存在着利率管制,直接补贴只能减轻学生还贷负担,间接补贴只能扩大资助面,且二者的资助绩效各不相同。由于现行的混合补贴方案存在着效率缺失,政府可放松利率管制,并将间接补贴转化为直接补贴,以改善资助效应。     

不恢复余数阵列除法器的FPGA实现

在研究不恢复余数法的算法基础上,阐述以可控加/减法器（CAS）为基本组成单元的阵列除法器的构造原理,并给出一个完整的定点小数补码除法逻辑图,最后提出一种基于现场可编程门阵列（Field-Programmable Gate Array,简称FPGA）的除法器的硬件实现方法.     

高中"数学情境与提出问题"的教学实践--"加法原理与乘法原理"教学案例

在高中阶段进行“数学情境与提出问题”研究是十分必要的。围绕“数学情境与提出问题”进行课堂教学应注意：(1)创设好的情境是进行课堂教学的基础；(2)恰当引导学生提出数学；(3)以单元大情境带动数学教学。     

水泥中Al_2O_3和Fe_2O_3含量的快速测定

报道了一种用差示分光光度法中的标准加入法快速测定水泥中AI_2O_3和Fe_2O_3含量的方法。此法对水泥生产有着很重要的意义。     

软新闻翻译的理论依据及其策略探究

根据时效性的强弱和语言风格差异,新闻大致可被分为：硬新闻,中间新闻及软新闻三类。为了达到应有的传播效果,实现原文及译文的功能及效果对等,软新闻翻译应该摆脱基于结构语言学的传统对等翻译理论的桎梏,取而代之以建立在功能语言学基础上的“目的论”为其翻译的理论依据,并通过适当的增添、删除和重组等“编译”手段,实现功能对等,使软新闻翻译达到更佳的翻译及传播效果。     

Acquisition and use of shortcut strategies by traditionally schooled children

This study aimed at analysing traditionally taught children’s acquisition and use of shortcut strategies in the number domain 20–100. One-hundred-ninety-five second, third, and fourth graders of different mathematical achievement levels participated in the study. They were administered two tasks, both consisting of a series of two-digit additions and subtractions that maximally elicit the use of the compensation and indirect addition strategy (, so the answer is 2 + 1 or 3). In the first task, children were instructed to solve all items as accurately and as fast as possible with their preferred strategy. The second task was to generate at least two different strategies for each item. Results demonstrated that children of all grades and all achievement levels hardly applied the compensation and indirect addition strategy in the first task. Children’s strategy reports in the second task revealed that younger and lower achieving children did not apply these strategies because they did not (yet) discover these strategies. By contrast, older and higher achieving children appeared to have acquired these strategies by themselves. Results are interpreted in relation to cognitive psychological and socio-cultural perspectives on children’s mathematics learning.

基于互联网的信息价值增值服务模式分析

新的网络应用需求不断增加,特别是第二代互联网(IPv6网)的发展,为进一步扩大网络应用范围,推动构建面向用户的专业信息化信息价值增值服务模式提供了充足的发展空间.     

单烯与共轭二烯亲电加成反应活性的比较

过从反应活性中间体的稳定性以及共价键的键长,从理论上说明共轭二烯比单烯易亲电加成。     

免疫荧光法检测扁平苔藓特异性抗原的研究

目的：为了证实扁平苔藓特异性抗原的存在．方法：作者对35例扁平苔藓(LP)进行间接免疫荧光(IIF)研究．结果：发现77．14％的病例在皮损处的颓粒层、棘细胞上层显示荧光沉积，但对照组14种其它皮肤病的30例病人也有46．7％的病例在同样部位显示荧光沉积．4例LP特异性抗原(LPSA)阳性的病人治疗前后分别做IIF法检查其结果均为阳性.结论：对以上结果分析，作者认为用IFF法检查不能证实LP有特异性抗原的存在，而所谓的“LPSA”也不能反映病情的变化．