火花质谱法及其在研究地化和宇化样品方面的应用

火花质谱法不须对样品进行任何化学处理,就可以测定固体物质中几乎所有的元素。这种方法不仅适用于主要元素,而且也适用于大多数微量元素,测定丰度可低达10~(-9)g/g数量级。所研究的样品放在高频火花中蒸发和电离,所形成的离子在一个双聚焦质谱仪中按照质量(确切地说是按照质量m与电荷e的比值m/e)分离开来,所形成的质谱谱线用相板记录,或者用一个灵敏的电气指示器记录。     

用氧化裂解和四极质谱检测法测定地面水中有机悬浮物的元素组成

本研究采用燃烧后四极质谱(QMS)检测装置测定地面水中有机悬浮物的元素组成。用离心法收集几种类型水中的固体物质。结果表明,本方法可用于水特性鉴定等方面。包括予处理和元素分析约需30分钟。无论水污染研究还是废物和天然有机物代谢机理的探讨,都越来越对地面水中不溶物内的有机质部分的元素组成感兴趣。有机质的组成极为复杂,因为它可能含有多种工业组分及脂肪、蛋白质和碳水化合物的代谢物。所以,进行全面的结梅分析以确定化合物的种类及其含量是不实际的而且几乎是不可能的。然而,元素分析可以给出化合物种类的有用信息,如脂肪或蛋白质的存在。最近Baumeister(1978)进行了地面水中悬浮物的CHN分析(即碳氢氮分析,译注)。他发现,各种不同试样的颗粒中C/N比率颇为一致。这可说明均来源于生物。     

全球化及大豆种植向阿根廷的半干旱生态系的扩展

砍伐森林是各自然、社会系统的地方特殊属性与通常在较大空间范围内发挥作用的驱动力量之间发生复杂相互作用的产物[1].社会与经济的全球化,特别是通讯与运输障碍的减少,已提升了全球环境变化(如砍伐森林)驱动因素的相对重要性.例如,农业的扩展正越来越强烈地受到在世界范围内迅速传播的农业技术改革的影响响[2],也因一些国家的巨大人口数量(如中国)或较高的生活水平(如美国、欧盟)而受到这些对全球市场造成不均衡影响的国家的消费方式变化的影响.     

Forest ecosystem development in post-mining landscapes: a case study of the Lusatian lignite district

The restoration of surface mining landscapes requires the (re)creation of ecosystems. In Lusatia (eastern Germany), large-scale open-cast lignite mining operations generated spoil dumps widely consisting of acidified, phytotoxic substrates. Amelioration and rehabilitation measures have been developed and applied to these substrates since the 1950s. However, it is still not clear whether these approaches are sustainable. This paper reports on collaborative research work into the ecological potential of forest ecosystem development on typical minesites in the Lusatian lignite district. At first sight, pine stands on minesites along a chronosequence comprising about 35 years did not show differences when compared with stands on non-mined sites of the general region. Furthermore, with some modification, conceptual models for flora and fauna succession in forest stands on non-mined sites seem to be applicable, at least for the early stages of forest ecosystem development. For example, soil organism abundance and activity at minesites had already reached levels typical of non-mined sites after about 20-30 years. In contrast, mine soils are very different from non-mined soils of the test region. Chemically, mine soil development is dominated by processes originating from pyrite oxidation. Geogenic, i.e. lignitic, soil organic carbon was shown to substitute for some functions of pedogenic soil organic matter. Rooting was hampered but not completely impeded in strongly acidified soil compartments. Roots and mycorrhizae are apparently able to make use of the characteristic heterogeneity of young mine soils. Considering these recent results and the knowledge accumulated during more than 30 years of research on minesite rehabilitation internationally, it can be stated that minesite restoration might be used as an ideal case study for forest ecosystem development starting at "point zero" on "terra nova".     

人与非洲猎豹相处的日子

我从路华汽车里小心翼翼地滑出来，带着大型摄影机以及各式各样的器材，这可不是件容易的事。     

Chinese life cycle impact assessment factors

ＩｎｔｒｏｄｕｃｔｉｏｎＬｉｆｅｃｙｃｌｅａｓｓｅｓｓｍｅｎｔ(ＬＣＡ)ｉｓａｎｅｎｖｉｒｏｎｍｅｎｔａｌｍａｎａｇｅｍｅｎｔｔｏｏｌｔｈａｔｉｓｕｓｅｄｔｏｅｘａｍｉｎｅａｎｄｅｖａｌｕａｔｅｔｈｅｅｎｖｉｒｏｎｍｅｎｔａｌｉｍｐａｃｔｓａｓｓｏｃｉａｔｅｄｗｉｔｈｔｈｅｅｘｉｓｔｅｎｃｅｏｆｐｒｏｄｕｃｔｓ(Ｊｅｎｓｅｎ,1998;Ｗｅｉｄｅｍａ,1997;Ｗｅｎｚｅｌ,1997).ＴｈｅｆｏｃｕｓｏｆＬＣＡｉｓｏｎｔｈｅｅｎｔｉｒｅｌｉｆｅｃｙｃｌｅｏｆｔｈｅｐｒｏｄｕｃｔ,ｉ.ｅ.ｆｒｏｍｔｈｅｅｘｔｒａｃｔｉ…     

污泥制砖

废水处理厂的污泥带来诸多处置难题。通常,脱水污泥用土地回收或填埋法处置。然而,对于高度都市化的城市来说,因土地有限,采用填埋法处置污泥可能是不合适的焚烧或许是一种较好的处置方法,经焚烧处理后会产生相当多的污泥烟灰,这些烟灰必须用其它方法来处置。本文介绍了用干污泥和污泥烟灰作为制砖材料的研究结果。制砖时,能与粘土相混合的干污泥和污泥烟灰的最大百分数分别为40％和50％,砖的抗压强度从不含污泥时的87.2N/mm~2减少到含干污泥40％时的37.9N/mm~2和含污泥烟灰50％的69.4N/mm~2     

金刚石是在老的富集型地幔中形成的

<正> 虽然一个多世纪以来,金刚石一直是从金伯利岩筒中回收的,但它们与金伯利岩主岩的关系却一直有争议。争论的焦点是,在原始金伯利岩浆中,金刚石究竟是斑晶还是捕虏晶?更广义地说,金刚石的结晶作用是在时间和空间上可能与金伯利岩的生成有关,还是在金刚石     

测定岩石、矿物及有关材料中SiO_2的准确分光光度法

<正> SiO_2是岩石、矿物和有关材料中的主要组分,经常需要准确测定。用于测定SiO_2的分光光度法主要有两种,即应用黄色钼硅酸络合物的方法和应用钼兰络合物的方法。 黄色络合物不大灵敏。同时基于黄色钼硅酸络合物的方法还存在由于形成混合的钼硅酸而造成的不稳