Analysis of individual natural pyrethrins in indoor matrices by HRGC/ECD

An HRGC/ECD method is presented which permits the identification and quantitation of individual components of pyrethrins (cinerin I, jasmolin I, pyrethrin I, cinerin II, jasmolin II, pyrethrin II) in indoor matrices (airborne particles, house dust) after application of an agent containing pyrethrum. In order to prepare calibration standards for the individual components of the pyrethrum extract, the pyrethrins were isolated hy semi-preparative HPLC and their content and purity were determined by ¹H-NMR spectroscopy.     

表面扩散的Monte Carlo初探

利用ＭｏｎｔｅＣａｒｌｏ方法模拟了理想表面和分形表面上的扩散过程；通过模拟可以发现，表面扩散系数不仅与表面浓度有关，而且还与扩散的时间、表面的几何形貌等有关。在表面覆盖度比较高时，表面扩散系数有一极大值。与理想表面相比，分形表面会使扩散系数减小。     

广州新建住宅空气中甲醛的分析

利用SKC便携式甲醛检测器对一新建住宅群 (7栋252套 )室内空气的甲醛含量进行抽样测定,测定结果在0.070～0.373mg/m3之间 ,大部分超出了美国和加拿大的0.1×10 -6(φ)的室内空气质量标准,以及我国的0.080mg/m3 的标准,分析结果表明木制品是室内装修甲醛污染的主要来源     

Effect of insignificant bias and its uncertainty on the coverage probability of uncertainty intervals: Part 2. Evaluation for a found insignificant experimental bias

This paper continues in studying the coverage probability of uncertainty intervals. It particularly investigates the uncertainty intervals determined in compliance with the GUM and EURACHEM Guide in case of the results uncorrected for the systematic error, since the experimental bias has been found insignificant. The problem is solved for known values of the experimental bias, its standard uncertainty and the overall standard uncertainty. The obtained findings given in graphs and tables show that coverage probability of the uncertainty intervals defined by expanded uncertainty about the uncorrected results can considerably fall below the chosen level of confidence; this depression depends only on the ratio of the bias and the overall uncertainty. The bias uncertainty does not directly influence this depression, it only determines whether the bias is significant or not and thereby determines whether the results will be corrected or not. The paper proposes three methods how to remove this coverage probability reduction: to apply a higher level of confidence in the significance test, to correct the results with the insignificant but too high biases and to compute the uncertainty intervals defined by some type of the uncertainties enlarged with the insignificant bias.     

生物洁净技术若干误区辨析

对生物污染因子控制与生物净化经常遇到的一些认识上的问题进行了探讨。认为如不解决这些问题就难以对微生物污染实施更有效控制,也难以将我国微生物控制与生物净化的研究提高到一个新的水平。     

浅析多元通风

本文主要讲述多元通风的概念、国内外发展现状、多元通风的优点、多元通风的分类及其预测与设计方法,并在文章最后提出多元通风系统今后研究及发展方向。     

室内外空气污染物的耦合关系及提高室内空气品质的措施

利用几种不同的物理模型对室内外空气污染物的耦合关系进行了数学表达,分析了空气过滤器的空气净化原理,讨论了位于不同处理过程的过滤器对于提高室内空气品质(IAQ)的作用。     

一种基于无交集节点分组的无线传感器网络覆盖算法

无线传感器网络是一种无线自组织网络,它由大量能量有限的传感器节点组成.能量消耗和网络覆盖是无线传感器网络的两个核心问题,网络覆盖决定了无线传感器网络对物理世界的监测能力,能量消耗则决定了无线传感器网络的生存时间.本文研究了一种改进的基于无交集节点分组算法,针对随机选取节点实现无交集节点分组方式获得的分组个数少且节点通信...     

舒适性空调系统的颗粒污染物控制--改善IAQ的步骤之一

要改善室内空气品质就必须对室内空气中的污染物质加以控制。针对八成生空调对空气过滤重视不够的现状，本文主要讨论影响室内空气含尘浓度的各个因素及其影响方法，并对舒适性空调系统的粉尘控制进行探讨。通过理论分析，本文首次提出系统临界过滤效率的概念，并从中得出舒适性空调系统空气过滤器的计算和选择方法供参考。     

基于矩阵形式的否定选择算法研究

现有的状态空间表示形式和匹配规则已经成为否定选择算法研究的瓶颈。为此,该文将状态空间从向量扩展到矩阵,提出了一种基于矩阵形式的否定选择算法。引入矩阵表示自我和非我空间,定义了元素匹配距离,在此基础上建立了双向匹配规则;同时根据状态空间特征建立了基于覆盖检验的检测器生成算法。实验结果表明该算法性能明显优于实值否定选择算法,有效解决了检测率和误报率联动的问题,且能产生更为高效的检测器。