石英柯石英的相变及其在活塞-圆筒装配上用滑石-铝硅镁-玻璃(TAG)和NaCl做高压腔体的比较摩擦测量的讨论

<正> Akella(1979)通过石英柯石英在800℃和1000℃下相变的再研究,对活塞圆筒装置上固体传压介质TAG和NaCl腔体进行了比较。虽然Akella提供的资料和前人的结果在总体上似乎符合得很好,但仔细分析便发现,他们既没有更精确地标出石英-柯石英的相界,在讨论固体传压介质高压腔体的摩擦问题上,也没有取得真正的进展。特别对后一个问题,进行更详细的讨论似乎是应当的,因为Akella所提出的有关摩擦的观点,看来还缺乏足够的实验证据。这种观点应用到NaCl腔体上尤其如此,所得出的结论比新见解带来更大的混乱。     

碳氮同位素在石油勘探中的应用

一、引言 天然气和石油起源于沉积在沉积盆地中的有机质。这种物质绝大部分属于海相成因,但也有经陆地上的雨水、风和河流带入的陆源有机质。这种物质在未固结的沉积物中受到细菌的分解并转化成含O、N、S的     

根据实验室资料将化合物分类和制订水质基准的建议

A、基本原理 在工业发达和人口过密的荷兰,水生态系统至今仍因人类将大量天然的和非生物的(Xenobiotic)化合物排入地表水而受到威胁。尽管荷兰政府对地表水中的一     

德意志联邦共和国五座城市的大气悬浮物中的135种多环芳烃

多环芳烃(PAH)产生于有机物的未完全燃烧过程,并以气态或附于液态和固态颗粒上散发到大气中去。PAH的数量以及各种PAH之间的数量比例,也就是PAH的分布情况,在很大程度上与燃烧过程有关,甚至于可以说不同的散发情况会有各自典型的分布。 然而我们主要感兴趣的不是排放的PAH分布与人体负荷的关系,而更多的是关心实际吸入的PAH情况。这一点既和各项排放有关也与PAH从排放到被大气吸收的变化有关。     

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     

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.