颗粒物采样和测定的进展

“当前,颗粒物的采样和测定技术是费钱、烦琐,并且达不到所希望的准确度。如果颗粒物采样的工艺学得到了重要的改进,将会有下列各项好处: ·更好地理解和定量掌握控制装备的动作,这样又可反过来有利于高效控制装     

大气质量影响分析(二)

二、评价方法 大气质量影响分析应包括以下五个要素: 1.现有环境——描述建设项目所在地区的现有环境。 2.环境影响——描述建设项目建成使用后对大气质量的影响。 3.缓和措施——描述为了缓和由于建设项目引起的大气质量下降,预计采取的措施。 4.替代方案——描述为了减少由于建设项目引起的大气质量下降,对可能采用的设计方案的修改。     

前寒武纪地盾的金矿勘查趋势

<正> 引言目前,全世界正以空前的规模从事前寒武纪地盾区中脉状金矿床的勘查工作,其原因有:(1)黄金价格上涨(估计40年后每克黄金值1.13美元),使过去不引人注目的找矿对象变成了富有生命力的勘查项目;(2)地盾区开采的其它金属(贱金属、镍、铁和铀)相对滞销,势必将勘查的注意力进一步集中到金矿上来;     

亚利桑那州富含 K_2O 的火山岩的分布:皮卡乔峰滑脱断层上的交代作用

<正> 前言亚利桑那州火山岩的K_2O含量高达12—13(重量)%,这些火山岩被称为粗安岩、超钾质粗面岩和碳酸岩、高钾粗面岩和粗面岩,Sh-afiqullah等将它们作了相互间的对比。然而,这些岩石的原始化学组成已经发生了实质性的改变,并提出采用“交代岩”这个术语。相对于高钾火山岩而言,这些蚀变岩石的K_2O含量     

环境影响与经济结构的关系——投入产出法

一污染是日常经济活动的一种副产物。各种形式的污染与某些特定的消耗和生产过程有着定量关系。例如:大量排入大气的一氧     

Triclosan in waste and surface waters from the upper Detroit River by liquid chromatography-electrospray-tandem quadrupole mass spectrometry

Triclosan (5-chloro-2-(2,4-dichlorophenoxy)phenol) is an antimicroibial disinfectant agent used in a wide array of consumer products. An analytical method based on solid-phase extraction (SPE) followed by reverse phase, liquid chromatography coupled with electrospray ionization (negative)-tandem quadrupole mass spectrometry (LC-ESI(-)-MS/MS; in the multiple reaction monitoring (MRM) mode) was developed, optimized and validated for the determination of triclosan in wastewater/sewage treatment plant (WSTP) effluent and surface waters from the upper Detroit River (Canada). The mean recoveries (+/-%RSD) of triclosan and the internal standard 2'-HO-tribromodiphenyl ether (2'-HO-BDE-28) spiked to surface water and WSTP effluent samples ranged similarly from 104+/-8% and 91+/-10%, respectively, and method limits of quantification were in the low ppb/high ppt range. However, ESI(-) enhancement was found for both analytes due to sample matrix effects, as indicated by % process efficiencies (a measure of ESI(-) enhancement/suppression), which were in the 111-128% range. We report the first known assessment of triclosan in the Detroit River watershed of the Great Lakes, which preliminarily examined the presence and UV-treatment effects on triclosan in effluent from the major WSTP serving the City of Windsor, Ontario, Canada, and fate in surface waters of the upper Detroit River. Triclosan in WSTP effluent decreased 22% after final UV treatment to a mean concentration of 63 ng/L. Concentrations were further reduced to 4 and 8 ng/L (a >90% reduction) in surface water samples from sites downstream on the Canadian shoreline of the Detroit River, which was due to dilution. Two hydroxylated tribrominated diphenyl ethers, which are structurally similar to triclosan, were also detected in WSTP effluent and surface water samples.     

Odour control at biowaste composting facilities

There are several options to effectively reduce odorous emissions at composting facilities depending on the type of composting system used. Some of the more relevant measures for open and enclosed composting facilities are presented in this article. Results from different investigations on odour reduction efficiencies of biological waste gas treatment systems at various scales are presented. Biofilter/bioscrubber combinations were used and different biofilter materials were tested. The more relevant odorous substances in the waste gas were identified, and their reduction in the different systems was measured. The biofilter proved to be mainly responsible for efficient odour degradation. The investigations presented in this article revealed that screened compost was very effective, and proved to be a low cost biofilter material for odour degradation purposes. Screened compost showed higher degradation rates than a coke-compost mixture newly developed by the University of Leipzig. Furthermore, it seems that enclosed systems have advantages when compared to conventional open single bed biofilters.     

Identification, structure elucidation, and synthesis of volatile compounds in the exhaust gas of food factories

Our investigations deal with the identification and synthesis of volatile, odoriferous compounds contained in the exhaust gas of food factories and on the biodegradation of alkylpyrazines. Collection of odour emissions samples was performed with a gas sampler equipped with filter tubes containing the styrene-polymer SuperQ. After elution with solvents of different polarity, the extracts were analysed by GC/MS and chemical microreactions. Proposed structures were verified by comparison of analytical data with those of synthetic reference samples. Major components in the exhaust gas of a fat finishing factory were found to be aliphatic aldehydes, strongly dominated by hexanal. The identification of 1,2,3,3-tetramethylcyclohexene shows that for structural proof of target compounds the use of authentic reference samples is indispensable. In the exhaust gas from a chocolate factory, several carbonyl compounds and alkylated pyrazines could be identified. Biodegradation of the latter starts with hydrogenation at the nucleus.     

Adsorption of arsenate on soils. Part 2: modeling the relationship between adsorption capacity and soil physiochemical properties using 16 Chinese soils

An attempt has been made to elucidate the effects of soil properties on arsenate adsorption by modeling the relationships between adsorption capacity and the properties of 16 Chinese soils. The model produced was validated against three Australian and three American soils. The results showed that nearly 93.8% of the variability in arsenate adsorption on the low-energy surface could be described by citrate-dithionite extractable Fe (Fe(CD)), clay content, organic matter content (OM) and dissolved organic carbon (DOC); nearly 87.6% of the variability in arsenate adsorption on the high-energy surface could be described by Fe(CD), DOC and total arsenic in soils. Fe(CD) exhibited the most important positive influence on arsenate adsorption. Oxalate extractable Al (Al(OX)), citrate-dithionite extractable Al (Al(CD)), extractable P and soil pH appeared relatively unimportant for adsorption of arsenate by soils.     

氧化铝—废水净化的吸附剂

前言最先开始运用固体活性氧化铝净化废水的是Feldmuhle股份公司,该公司研制了用活性氧化铝净化造纸漂白废水的方法,并在最近应用于工业规模的装置。据我们研究,氧化铝不仅可以吸附氯化木质素,而且可以很好地吸附其他多种物质,使含有这些物质的废水得以净化。