Identification of micro-scale calorimetric devices II

The miniaturized calorimetric devices furnish a reduced working flat surface and permits measurements with extremely low-mass quantities. The experimental sensitivity shows relevant position dependence with x-y surface coordinates and with z-distance. The device identification is realized via a 2-D model based in Fourier general equation. Using the Marquardt method the experimental flat surface device can be identified and the fitted parameters used to simulate the behavior of the experimental system. From the model, the effects of several dissipation configurations can be evaluated. Also, via the RC-analogy, a way to 3-D experimental devices is roughly described. This revised version was published online in July 2006 with corrections to the Cover Date.     

闭排队网络中性能势与无穷小实现因子之间的关系

In this paper,the concept of the infinitesimal realization factor is extended to the parameter-dependent performance functions in closed queueing networks. Then the concepts of realization matrix (its elements are called realization factors) and performance potential are introduced,and the relations between infinitesimal realization factors and these two quantities are discussed. This provides a united framework for both IPA and non IPA approaches. Finally,another physical meaning of the service rate is given.     

光回归反射织物的研究中粘合剂的选择

为了得到高反射率的回归反射涂层产品，本项目通过大量实验，生产出最佳的粘合剂及优选出其用量，并利用扫描电镜照片进行了分析。     

三种饲料添加剂对幼兔增重及饲料转化率的对比试验

对新球虫灵,喹乙醇,免健宝Ⅰ号,Ⅱ号配套复合饲料添加剂进行的幼兔饲养对比试验结果表明:以免健宝Ⅰ、Ⅱ号配套复合饲料添加剂联合效果为最佳,其它依次为单用兔健宝Ⅱ号、兔健宝Ⅰ号、喹乙醇,新球虫灵。而且兔健宝Ⅰ、Ⅱ号配套复合饲料添加剂有易混匀,简化配合饲料工序、节省饲料及增重快等优点。     

有限群为ρ-幂零群的一些充要条件

在文献[1]研究Ⅱ-超中心的基础上,取Ⅱ={p},即利用p-超中心得到了ρ-幂零群的另外一些充要条件,并推广了文献[2]介绍的ITo定理.     

用栅板剪切干涉法确定应力强度因子

本文介绍了一种用栅板剪切干涉法确定应力强度因子的新方法,阐明了该方法的基本原理与实验技术,通过三点弯曲梁确定了Ⅰ型裂纹应力强度因子,实验结果与理论上近似计算结果相符合。     

代谢综合征的流行病学调查与分析

目的：了解20岁以上成年人代谢综合征的发生率；对比分析其相关的危险因素及保护因素。方法：(1)通过1026名20岁以上成人体检，应用修订的代谢综合征的美国诊断标准，凡具备以下5项标准中3项及3项以上，即①体质指数(BMI)≥24，②甘油三酯ρ(TG)≥150mg／dL，③高密度脂蛋白胆固醇ρ(HDL—C)男＜40mg／dL、ρ(HDL—C)女＜50mg／dL，④空腹血糖ρ(FBC)≥110mg／dL，⑤收缩期血压(SBP)≥130mmHg或舒张期血压(DBP)≥85mmHg或SBP／DBP≥130mmHg／85mmHg(1mmHg＝0．133kPa)，诊断为代谢综合征，共检出136名为病例组。(2)从既往无高血压、糖尿病、冠心病及血脂异常史，且本次筛检未纳入代谢综合征的人群中，抽取与病例组性别、年龄相当的136名进行配对调查分析，计算其相关因素的χ^2值、P值、机会比(OR)值，以及机会比值的95％可信限(OR 95％CI)。结果：(1)从1026名中共检出代谢综合征136名，其发生率为13．26％；(2)调查分析发现摄入过量和长时间处于坐位而又缺乏运动两项可能为代谢综合征的危险因素；而运动可能是代谢综合征的保护因素。结论：(1)本次广东地区部分人群筛查20岁以上成人代谢综合征的发生率为13．26％，虽较美国人为低，但中年组为17．48％，老年组高达29．27％，必须引起重视；(2)坚持终身运动和合理膳食可能是预防代谢综合征的切实可行、经济、有效的措施。     

Kinetic features of ethylene polymerization over supported catalysts [2,6‐bis(imino)pyridyl iron dichloride/magnesium dichloride] with AlR3 as an activator

The effects of polymerization temperature, polymerization time, ethylene and hydrogen concentration, and effect of comonomers (hexene‐1, propylene) on the activity of supported catalyst of composition LFeCl₂/MgCl₂‐Al(i‐Bu)₃ (L = 2,6‐bis[1‐(2,6‐dimethylphenylimino)ethyl] pyridyl) and polymer characteristics (molecular weight (MW), molecular‐weight distribution (MWD), molecular structure) have been studied. Effective activation energy of ethylene polymerization over LFeCl₂/MgCl₂‐Al(i‐Bu)₃ has a value typical of supported Ziegler–Natta catalysts (11.9 kcal/mol). The polymerization reaction is of the first order with respect to monomer at the ethylene concentration >0.2 mol/L. Addition of small amounts of hydrogen (9–17%) significantly increases the activity; however, further increase in hydrogen concentration decreases the activity. The IRS and DSC analysis of PE indicates that catalyst LFeCl₂/MgCl₂‐Al(i‐Bu)₃ has a very low copolymerizing ability toward propylene and hexene‐1. MW and MWD of PE produced over these catalysts depend on the polymerization time, ethylene and hexene‐1 concentration. The activation effect of hydrogen and other kinetic features of ethylene polymerization over supported catalysts based on the Fe (II) complexes are discussed. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 5057–5066, 2007     

多线性Calderón-Zygmund算子的加权有界性

建立了多线性Calderón-Zygmund算子在比幂权空间更一般的Herz空间和Herz型Hardy空间上的有界性.作为推论,得到了该算子的幂权估计.在这些幂权估计中,权指标可以突破Ap权的指标限制,显示出和经典Calderón-Zygmund算子本质的区别.     

一类最高权向量环的Krull维数

本文给出Om×GLn作用于Cm,n上的复多项式环上的最高权向量环的Krull维数公式,从而改正了Aslaksen,Tan及Zhu的一个错误.