TNT基炸药机械加工用切削液

针对TNT基炸药及其机械加工特点，设计出对人和环境友好的CFE和ICFE系列TNT基炸药机械加工专用水基切削液配方，根据切削液的防锈性能、切削液与TNT基炸药作用的变色特性对配方进行了筛选和评价。     

钨硅系列三元杂多阴离柱撑阴离子粘土的合成及表征

采用离子交换法将过渡金属离了三元取代钨杂多阴离子引入Ｚｎ２Ａｌ型阴离子粘土层内，得到柱撑水滑石Ｚｎ２Ａｌ（ＯＨ）６－ＳｉＷ９Ｚ３Ｏ４０（Ｚ＝Ｔｉ＾４＋，Ｍｏ＾６＋）及Ｚｎ２Ａｌ（ＯＨ）６－ＳｉＷ９Ｆｅ３（Ｈ２Ｏ２）３Ｏ３７。ＺＲＤ及ＩＲ表明，杂多阴离子引入水滑石层间后，水滑石层内高度为１．０ｎｍ。     

痕量砷流动注射在线还原氢化物发生原子吸收测定

方法采用流动注射停流技术使水及土壤浸出液中Ａｓ（Ｖ）在线还原为Ａｓ（Ⅲ），不经手工还原，用氢化物发生原子吸收光谱法直接测定砷的含量。含４ｍｏｌ／Ｌ ＨＣｌ的样品溶液与３０％碘化钾溶液在编结式反应器中混合，并在采样环中停流４０ｓ，达完全还原后注入到载流中与硼氢化钠反应，采样速度５５次／ｈ，检出限（３δ）０．１μｇ／Ｌ，对自来水和土壤浸出液的加标回收结果满意。     

Numerical analysis of stress distribution in the upper arm tissues under an inflatable cuff: Implications for noninvasive blood pressure measurement

An inflatable cuff wrapped around the upper arm is widely used in noninvasive blood pressure measurement. However, the mechanical interaction between cuff and arm tissues, a factor that potentially affects the accuracy of noninvasive blood pressure measurement, remains rarely addressed. In the present study, finite element (FE) mod-els were constructed to quantify intra-arm stresses generated by cuff compression, aiming to provide some theoretical evi-dence for identifying factors of importance for blood pressure measurement or explaining clinical observations. Obtained results showed that the simulated tissue stresses were highly sensitive to the distribution of cuff pressure on the arm sur-face and the contact condition between muscle and bone. In contrast, the magnitude of cuff pressure and small variations in elastic properties of arm soft tissues had little influence on the efficiency of pressure transmission in arm tissues. In par-ticular, it was found that a thickened subcutaneous fat layer in obese subjects significantly reduced the effective pres-sure transmitted to the brachial artery, which may explain why blood pressure overestimation occurs more frequently in obese subjects in noninvasive blood pressure measurement.     

安捷伦为制药市场推出经验证的溶出度仪组件

2013年5月21日,北京安捷伦科技公司(纽约证交所:A)今日推出经验证的全新系列溶出度仪组件,包括一体成型溶出杯以及桨和转篮轴。这些组件经过专门设计,确保符合机械认证指南。组件将     

北京大学分析化学系列小班阅读讨论课的教学实践

简介了北京大学化学与分子工程学院分析化学系列基础课(定量分析化学、仪器分析、中级分析化学)开展小班阅读讨论课教学的实践。     

q-Deformed Gelfand-Dickey系列规范变换的行列式表示

Gelfand-Dickey系列是十分重要的可积系统.本文用规范变换来讨论q-Deformed GelfandDickey系列的解,得到了由两种基本规范变换迭代(n+k)次产生的规范变换算子Tn+k的行列式表达,并由此给出规范变换后的τ函数Tq(n+k)的形式.     

SOME REMARKS ON HOLOMORPHIC FUNCTIONS AND TAYLOR SERIES IN Cn

Some previous results on convergence of Taylor series in Cn [3] are improved by indicating outside the domain of convergence the points where the series diverges and simplifying some proofs. These results contain the Cauchy-Hadamard theorem in C. Some Cauchy integral formulas of a holomorphic function on a closed ball in Cn are constructed and the Taylor series expansion is deduced.     

Determinacy—A3是Co—Np完全的

群试(group testing)方法首先由Dorfman在第二次世界大战期间提出,当时是出于征兵验血的需要。现在,群试方法已应用于多门学科,诸如计算机科学,组合学及统计学等。可以把群试问题简述如下:设N是一个含有n个元素的集合,记为N={1,…,n},在N中有一些“坏”元素,我们试图通过一系列试验把全部“坏”元素找出来,如何使试验次数最少?我们把全体“坏”元素集称为样本,所有可能的样本形成样本空间。在这篇