CHARACTERIZATIONS AND RELATIONSHIPS BETWEEN OUTDOOR AND INDOOR BIOAEROSOLS IN AN OFFICE BUILDING

1.IntroductionBioaerosolsaremicroorganismsorparticles,gases,vapors,orfragmentsofbiologicalorigin(i.e.,aliveorreleasedfromalivingorganism)thatexistintheair.Bioaerosolsareeverywhereintheenvironment.Underfavorableconditions,bioaerosolsareabletogrowandpropagateonavarietyofbuildingmaterialsandindoorsurfaces,causingindoorairpollution.Therefore,owingtotheirubiquitouspresenceinnature,bioaerosolsasapollutionsourcearealmostinevitableinarangeofenclosedenvironmentsandincommunityair(Kodama&McGee,1986;Lig…     

THERMODYNAMIC AND PARTICLE-DYNAMIC STUDIES ON SYNTHESIS OF SILICA NANOPARTICLES USING MICROWAVE-INDUCED PLASMA CVD

1. Introduction1.1 Silica nanoparticles and synthesis methods Silica (SiO2) nanoparticles are widely used in industry asan active filler for polymer reinforcement, a rheologicaladditive in fluids, a free flow agent in powders, and anagent for chemical mechanical polishing during IC (inte-grated circuit) fabrication (Sniegowski & de Boer, 2000).Silica powder is also used for producing silicon carbide(Koc & Cattamanchi, 1998) or opaque silica aerosols (Leeet al., 1995). Many methods can …     

OFDMA中继系统中基于QoS保证的资源分配算法

研究了 OFDMA 中继下行链路通信系统中的动态资源分配问题,提出了一种可以保证用户最低 QoS 需求的资源分配算法.首先在简化资源优化问题的过程中,采用等功率分配方法以降低算法复杂度,然后通过拉格朗日松弛优化方法推导出了子载波分配和中继选择最优解,并在此基础上引入用户速率权衡因子,根据速率权衡因子越大的用户,越具有选择子载波和中继的优先权这一准则进行子载波分配和中继选择.仿真结果表明:新算法能够获得较高的系统容量,同时也能很好地保证不同用户的最低速率需求.     

基于PIV测量的水击谐波场中分散相粒子的湍流特性分析

为了解油中分散相粒子的微观运动状态,利用图像采集系统对水击谐波场作用下油中分散相粒子的微观运动状态进行了采集和处理,通过对分散相粒子的湍流特性的PIV(Particle Image Velocimetry)测试,探讨了激振力产生水击谐波的油水分离效果。结果表明:随着施加激振力的增加,粒子在波节(18.2mm)的附近出现了较为明显的聚集涡流和在波腹(68.2mm)的附近出现了明显的发散涡流;粒子的湍流动能、耗散率有两个明显的分布较大的区域,分别对应流场图中的粒子发散涡流、粒子聚集涡流区域与实验管道底部的交界面,而且随着激振力的减少,粒子的湍流动能、耗散率由两个明显的分布较大的区域变为只有一个明显的分布较大的区域,该区域都是含能涡的直接体现。     

Synthesis and gelation behaviors of five new dimeric cholesteryl derivatives

Five new diacid amides of di-cholesteryl L-glycinates were designed and prepared.The compounds with linkers containing 0,1, 2,3,or 4 methylene units are denoted as 1,2,3,4,and 5,respectively.Their gelation behaviors in 25 solvents were tested as novel low-molecular-mass organic gelators(LMOGs).It was shown that the length of the linker connecting the two-cholesteryl residues in a gelator plays a crucial role in the gelation behavior of the compound.1 gels 11 of the 25 solvents tested at a concentration lowe...     

基于分子内电荷转移的阴离子比率荧光分子探针

设计合成了一种基于4-甲基-1-羟基二苯甲酮对硝基苯腙的比色和比率荧光阴离子受体1。此类受体以羟基和腙单元为识别位点,以硝基苯基为信号报告基团。向受体1的DMSO溶液中加入AcO-、H2PO4-、F-后,溶液颜色由黄色变为紫红色,而加入所研究的其它阴离子则无变化,从而实现对AcO-、H2PO4-、F-这三种离子的裸眼识别。利用紫外-可见吸收光谱、荧光光谱考察了其与AcO-,H2PO4-,F-,Cl-,Br-,I-等阴离子的识别作用。1H NMR滴定为受体分子与阴离子之间氢键作用本质提供了有力证据。     

荧光法研究meso-四对羧基苯基卟啉与牛血清白蛋白的作用机理

应用荧光法研究了meso-四对羧基苯基卟啉(TCP)与牛血清白蛋白(BSA)的结合反应.通过Stern-Volmer方程和Lineweaver-Burk双倒数函数关系式,测得25℃,36℃和42℃下反应的动态猝灭常数Ksv分别为1.17×105,1.06×105,1.01 ×105 L·mol-1,静态猝灭常数KLB分...