水布垭水电站右岸防淘墙设计方案施工优化

水布垭水电站右岸防淘墙工程规模大、工程地质条件复杂、施工工期紧、危险性大,由于施工中参建各方的共同努力,对施工设计方案进行了优化,先后克服了地质条件差、塌方、大流量渗水等难题,从而确保了防淘墙全线提前完工,为电站尾水系统施工赢得了时间,也为水布垭水电站按期发电奠定了坚实的基础。     

工作面煤层底板注浆改造工艺在车集矿的应用

介绍了车集矿2404工作面底板注浆改造工艺实践经验、成果及效果评价与验证，解决了在典型的华北型沉积煤田高水压、厚隔水层、复杂的裂隙条件下进行井下造浆、注浆等防治水方面的难题。     

纤维表面处理对植物纤维增强水泥的物理力学性能影响

植物纤维增强水泥的力学性能具有湿敏感性，随湿度增加弯曲强度下降幅度较大。本文工作采用的几种浸渍处理纤维表面的方法，有效地改善了这种状况，其中一种经处理的纤维增强水泥较没有处理的对比试样在饱水状态下的弯曲强度提高了67％，气干状态提高了18％，缩小了二者间的差距。     

介绍《电工电子实践课程丛书》--东南大学电工电子系列实践课程教改成果之一

本文介绍由东南大学组织编写，东南大学出版社出版的《电工电子实践课程丛书》的编写背景，每本教材内容的简要内容，特色与使用情况。     

A new alloy design concept for austenitic stainless steel with tungsten modification for bipolar plate application in PEMFC

The feasibility of a new alloy design concept utilizing the principle of ‘tungsten bronze effect’ is critically evaluated for the development of metallic bipolar plates for proton exchange membrane fuel cell (PEMFC). An austenitic stainless steel (ASS) is modified with W and La to improve the stability of the passive film in an acidic environment as well as to reduce the contact resistance by the tungsten bronze effect. The experimental ASS containing W and La was evaluated in a simulated PEMFC environment of H₃PO₄ and H₂SO₄ solutions at 80 °C, and the electrical property was evaluated by performing a contact resistance test. The test results show that the ASS modified with W and La has good passive film stability for corrosion resistance and low contact resistance. The X-ray photoelectron spectroscopy (XPS) analysis clearly suggests the possibility of the tungsten bronze effect from the change in valency state of W⁶⁺ to W⁵⁺ in the passive film formed on the modified ASS. The feasibility of a new alloy design concept utilizing the ‘tungsten bronze effect’ is well demonstrated; however, more study is highly required for the development of metallic bipolar plates of PEMFC.     

岩石样品中铷的中子活化分析

研究了苦味酸溶液的ｐＨ变化对用１８－Ｃ－６（１８Ｃ６）的硝基苯溶液定量萃取Ｒｂ的影响及１８Ｃ６浓度变化对定量萃取Ｒｂ的影响，确定了定量反萃Ｒｂ的实验条件。作出了磷酸锆无机离子交换柱上的Ｒｂ－Ｃｓ分离曲线。测定了岩石样品的微量Ｒｂ和痕量＾８４Ｒｂ。     

PYY in developing murine islet cells: comparisons to development of islet hormones, NPY, and BrdU incorporation

Exhaustive characterizations of antisera to the structurally related peptides pancreatic polypeptide (PP), neuropeptide Y (NPY), and peptide YY (PYY) enabled us to establish the developmental pattern of these peptides in rat and mouse pancreas. PYY was the earliest detectable peptide and was present in all early appearing endocrine cell types. NPY appeared later and occurred exclusively in a subpopulation of insulin cells, whereas PP cells arose latest. At the earliest stage studied, all endocrine cells stored PYY. Most of these cells also contained glucagon. Subsequently, the endocrine cells comprised glucagon+PYY cells and glucagon+PYY+insulin cells. Later, cells storing either only insulin or insulin+PYY appeared. Quantitations of the relative numbers of these cell populations during development were consistent with a precursor role of triple-positive (insulin+glucagon+PYY) cells. Moreover, bromodeoxyuridine (BrdU) injections at E15.5 showed that a large percentage of triple-positive cells were in S-phase and therefore were actively dividing, whereas almost no pure insulin cells or insulin+PYY cells synthesized DNA at this time. These results suggest that PYY-positive endocrine cells may represent precursors for mature islet cells.     

编程绘制数学曲线的探讨

通过编写程序输出数学曲线,具有一定的趣味性,可以开阔编程视野。只要具有初级程序设计能力,再结合有关数学知识就能实现。程序设计的思想是利用数学公式求得多个位置值,用Tab函数定位,用Print语句在这些位置上分别输出符号“”,从而得到由多个“”组成的数学曲线,例如三角函数曲线、抛物线曲线、半圆曲线及概率曲线等。