加拿大对饮水中Ca、Cd、Co、Cr、Cu、Mg、Ni、Pb和Zn含量两次全国调查所取得的成果

加拿大对饮用水中的微量元素Cd、Co、Cr、Cu、Ni、Pb和Zn进行了两次全国性调查。调查中包括Ca和Mg。为了检验水净化和水分配过程中水的质量,对70个城镇的天然水,净化水和自来水进行了取样分析。采用两种方法:石墨炉原子化器和吡咯烷二硫代氨基甲酸铵(APDC)萃取法对Pb、Cr和Cd进行了直接分析,並对所取得的结果加以对比研究。结果表明,微量元素分析一般並不因为有固体微粒而受到影响。水中查出的有毒元毒的浓度比允许的最大值低得多。在水净化和分配给用户过程中,这些元素的浓度除Cu以外几乎都没有增加。     

用同位素数据说明碳氢化合物中H_2S和CO_2的成因

<正> 酸性化合物总是存在于碳氢化合物中,其含量从百分之一到百分之几十。一方面,它们是讨厌的杂质(特别是H_2S),给勘探和野外工作带来很大麻烦;另一方面,它们又可能是难得的原料来源。由于在苏联几个地区——里海凹陷、Amu-Darya陆槽和西西伯利亚地台——发现了含     

Construction of Vertical Wind Profile from Satellite-Derived Winds for Objective Analysis of Wind Field

During summer Monex-79, a variety of observing systems viz. research ships, research aircrafts, constant pressure balloons and geostationary satellite etc. were deployed, besides the regular conventional observations. The purpose of these additional systems was to make the best possible data for the studies on various aspects of monsoon circulation. The present study is aimed at the construction of vertical wind profile using cloud motion vectors obtained from GOES (I-O) satellite and to examine whether the constructed wind profiles improves the representation of the monsoon system, flow pattern etc. in the objective analysis. For this purpose, climatological normals of the wind field are considered as the initial guess and the objective analyses of the wind field are made with, first using only data from conventional observations over land areas, subsequently including the constructed winds from cloud motion vectors. These analyses are then compared with the standard analyses of wind field obtained fro     

AUSTRALIA-CHINA COOPERATION IN METEOROLOGY

Australia and China are two countries of comparable geographical size spanning similar latitude rangesin roughly the same longitudes yet with vastly different populations,histories and social structures.Thelinks between the two countries have developed rapidly over the past fifteen years,in few areas more-sothan meteorology,one of the most inherently international of all fields of human endeavour.This paperbriefly compares the historical development and current organization of meteorology in the two countries andreports on the highlights of a program of enhanced bilateral cooperation begun in 1985.     

LARGE SIGNALS OF CLIMATIC VARIATION OVER THE OCEAN IN THE ASIAN MONSOON REGION

The aim of this paper is to identify and delineate large signals of climatic variation in the Asian monsoon region and try to understand the nature of transformation from one climate regime to another.It is found that the summer monsoon over the Indian and western Pacific oceans shows distinct climatic regimes with changes occurring in the years around 1875, 1900, 1940 and 1960. The change of about 1900 is the largest one, which occurs in step with the variation of global oceanic climate pointed out by Fletcher, et al.(1982).The main characteristics of the transformation from one regime to another is an alternation of meridio-nality of monsoon current. The transformation occurs most strongly in the western Pacific convergence zone, where monsoon has strong interaction with the trade wind systems.The variability of monsoon rainfall over India and East China also exhibits some large signals which are synchronous with those of wind field over the ocean: the monsoon rainfall increases (decreases) during the     

东布什维尔德杂岩体铬铁矿矿床的产状及特征

东布什维尔德杂岩体东布什维尔德杂岩体的铬铁矿矿床产于"东部苏长岩带"中,产在层状的大片基性至超基性岩内(图1).很早以前,A.L.霍尔把沃利凡次河到斯蒂尔普特河分布的那一部分岩带,划分了如图2所示的五个主要单元.本文重点讨论其中的临界带,因为正如霍尔所确定的,该带含有东带所有的已知铬铁矿矿床.临界带以其层状构造闻名于     

英国地理学家协会的五十年

今年一月,英国地理学家在爱丁堡聚会,庆祝英国地理学家协会成立五十周年。协会成立于1933年,其主要宗旨是创办刊物,发表地理学家的研究成果。背景第一次世界大战后,英国大学地理系发展很快,为此,整个国家的地理研究工作也不断得到加强。     

A closed form slug test theory for high permeability aquifers

We incorporate a linear estimate of casing friction into the analytical slug test theory of Springer and Gelhar (1991) for high permeability aquifers. The modified theory elucidates the influence of inertia and casing friction on consistent, closed form equations for the free surface, pressure, and velocity fluctuations for overdamped and underdamped conditions. A consistent, but small, correction for kinetic energy is included as well. A characteristic velocity linearizes the turbulent casing shear stress so that an analytical solution for attenuated, phase shifted pressure fluctuations fits a single parameter (damping frequency) to transducer data from any depth in the casing. Underdamped slug tests of 0.3, 0.6, and 1 m amplitudes at five transducer depths in a 5.1 cm diameter PVC well 21 m deep in the Plymouth-Carver Aquifer yield a consistent hydraulic conductivity of 1.5 x 10(-3) m/s. The Springer and Gelhar (1991) model underestimates the hydraulic conductivity for these tests by as much as 25% by improperly ascribing smooth turbulent casing friction to the aquifer. The match point normalization of Butler (1998) agrees with our fitted hydraulic conductivity, however, when friction is included in the damping frequency. Zurbuchen et al. (2002) use a numerical model to establish a similar sensitivity of hydraulic conductivity to nonlinear casing friction.     

IP法几种常用电极排列的比较

激电工作使用的电极排列有多种,应根据工作目的、地质条件和需要信息量选其一种进行工作,否则不但得不到预期效果,而且浪费资金。遗憾的是有这种倾向,某种电极排列得到偏爱,不分场合照例使用,对其它电极排列的特点则考虑不多。论述各种电极排列优缺点的文章不多,虽通过模型实验结