Observation of the nighttime nitrate radical in Hefei, China

Observation of nighttime nitrate radical (NO3) was performed by using long path differential optical absorption spectroscopy (LP-DOAS), on the outskirts of Hefei, China. The time series of NO3 and supporting parameters were simultaneously measured for a week (31 May-7 June 2006). The results indicated that the average concentration of NO3 was 15.6 pptv with an average lifetimes of 96 s, whereas, NO3 production rates varied from 8×105/(cm3·s)to 2.98×107/（cm3·s）. Furthermore, the calculated N2O5 concentration averaged at 380 pptv. Analysis of data indicated that direct sinks were probably dominating the NO3 loss process during this campaign. Finally, the results were compared with other campaigns in the boundary layer.     

浸渍活性炭脱除含硫气体研究进展

介绍了浸渍活性炭脱除含硫气体机理的研究进展,归纳了炭表面化学环境,金属离子及水对转化途径和反应机理的影响,对进气组成和温度、压力、空速等操作条件对脱硫效率的影响进行了讨论,举例说明了浸溃活性炭脱硫应用情况,分析了浸渍活性炭失活原因,对再生方法进行了简要总结。     

水质转化的现代科学与技术：兼谈环境水化学实验室的科研方向

本文综述了当前环境水化学的发展趋势及其中苦干部分的研究动态与方向，例如：化学形态分布、酸化与风化、表面络合、沉积物质量评价、生态毒理、水陆交错带、水处理中的絮凝、膜分离、化学氧化、生物氧化和水质模式。离作者的若干观点及对环境水化学实验室近期研究方向的一些看法。     

Antioxidant alteration ofGlycine max (Fabaceae) defensive chemistry: Analogy to herbivory elicitation

Summary The water-soluble antioxidant, L-ascorbic acid (vitamin C), proved elicitory to alterable anti-herbivory inGlycine max againstTrichoplusia ni larvae. Elicitation by vitamin C was influenced especially by dose, time after elicitation and space in the plant. Results allow an analogy between antioxidant and herbivory elicitation. Elicitation apparently involves a sulfhydryl-protein-dependent redox mechanism which can be significantly affected by antioxidants. Findings would also support a proposed common redox-based mechanism, involving the plasma membrane, for communication between plant and animal cells and their environments.     

大气污染化学研究概况

本文综述了大气污染化学研究在国内外的发展概况,对大气污染物的表征研究和大气污染的化学过程与模式的研究,作了详细的阐述,特别对大气颗粒物的表征与来源的识别、大气光化学反应、自由基反应及其它活性物种的反应在近年的发展作了全面的总结,介绍了当今全球性大气污染的一些重大环境问题,如酸雨、臭氧层破坏、温室效应等有关大气化学研究的情况,回顾了大气污染化学对中国经济与科学发展中的重要作用。     

Chemistry of preen gland secretions of passerines: different pathways to same goal? why?

Summary. Passeriformes is the largest order of birds and includes one third of the bird species of the world, living in very diverse habitats. We investigated the chemistry of preen gland secretions of some groups of passerines from temperate regions found in diverse microhabitats. Some of the common components were mixtures of homologous monoesters made up of long chain acids and alcohols. Individual species had characteristic distribution of esters and was unique to a given species, although there were some individual variations. We compared the composition of acids and alcohols that formed same molecular weight esters in different species and we found that the combination of acids and alcohols to arrive at same molecular compositions varied distinctly between species. To compare compositions of over all acids and alcohols that formed the esters, the representative samples of secretions from the individual species were transesterfied the produce methyl esters and alcohols. We found that there were distinct differences in number of acids and alcohols that produced the combination of homologous mixtures of esters. Also they differed both qualitatively and quantitatively. There were also seasonal differences in the secretion components. Thus though the intact mixtures of esters in individual species had some similarities, they were very complex mixtures and differed characteristically for individual species. Here we discuss possible causes for evolution of these variations. We suggest that the evolution in variation of preen gland secretion is probably due to selective pressures caused by ectosymbionts such as feather-mites and feather-chewing lice that live on feathers and probably feed on the secretions and surrounding environments     

电解制备高效聚合铝的溶液化学因素

采用电化学方法合成聚合氯化铝，通过在线有效控制电解过程的关键参数，可以年鉴轩出高碱化度，高Ａｌｂ含量的ＰＡＣ液体产品，本文研究了ＰＡＣ电合成的重要溶液化学因素，如电解液的性质、浓度、组成、ｐＨ、离子迁移，形态转化等，从而提出了制备设定浓度和碱化度的ＰＡＣ的最佳溶液化学条件，并证明溶液化学因素与电量参数之间具有必然联系。     

Population-level variation in plant secondary chemistry,and the population biology of herbivores

Summary Modern population ecology is becoming increasingly spatially-explicit. For insect hervibores, spatial variation in plant quality is a critical component of distribution and abundance. We argue that populationlevel measurements of phytochemical variation among individual plants has not kept pace with recent developments in population ecology. With examples from our own work, we demonstrate the importance of spatial variation in plant chemistry for insect herbivores, and suggest that phytochemistry should play a central role in the development of any spatially-based ecological theory.     

ⅠA族和ⅡA族金属的消烟助燃效应及其理论

ⅠＡ三金属和ⅡＡ碱土金属元素是有灰型消烟助燃剂的功能元素，就各族内而言，这些ｓ区金属元素的消烟助燃效应与它们的热电离电离热成反比，此特征与烃火焰条件下碳烟生成的正离子机制有关，就两族间而言，ⅡＡ族金属的消烟助燃效应通常大于ⅠＡ族金属，该特征与ｓ区金属元素的火焰电离特性有关，在实质上，ｓ区金属元素的消烟助燃效应与它们在火焰条件下发生电离的活化能有关，基于碳烟生成的双途径模型，含ⅠＡ，ⅡＡ族金属消烟助     

环境样品前处理技术及其进展（一）

本文讨论了环境分析化学中样品制备及前处理技术的现状及其进展。有关环境样品的特点、前处理的目的及其作用、选择前处理技术的依据等也做了阐述。重点评述了近年来在环境分析化学领域中发展最快、用得比较普遍的几种新方法，即超临界流体萃取、固定萃取、微波溶出和液膜萃取等。（一）介绍样品前处理的原则和有关的基础，以及超临界流体萃取法；（二）其它方法及今后的发展动向（将刊登在《环境化学》１９９４年第二期）。