砷的仪器分析方法新进展

砷是自然界中广泛存在的一种物质在工业，农业，医药等方面应用很广。笔者着重介绍了近几个来砷的仪器分析方法新进展，主要有光度法，电化学法，原子吸收法等。     

高温高压下水岩界面反应与金的迁移富集

高温高压下水岩界面反应与金的迁移富集王玉荣阚小凤王志强（中国科学院广州地球化学研究所，广州５１０６４０）关键词水岩界面反应自发电池实验地球化学本实验以哈达门沟［１］及东坪金矿［２］为地质背景，研究钾长石岩中金矿化富集的物理化学条件。该区金矿既与早期变...     

对GB／T 19001—1994 idt ISO9001：1994标准的浅解和探讨

文章是对ＩＳＯ９００１标准精神的一些理解，并对该标准中一些条文规定展开讨论。     

地气测量在内蒙老羊壕金矿区的某些试验成果

以内蒙老羊壕金矿区为试验基地 ,引进抽气法地气测量 ,探讨了地气测量在内蒙干旱荒漠区寻找浅覆盖区隐伏金矿床的有效性。并以试验资料为依据 ,初步探讨了抽气法地气测量中的若干问题 ,指出了抽气法地气测量中存在微尘颗粒干扰。对寻找隐伏金矿床的多元素地气测量 ,采用经 0 .2 2 μm微孔滤膜过滤泡沫塑料吸附为好。已有资料显示可能有超微粒 (接近纳米级 )物质自深部矿体迁移上来     

STUDIES ON TERRACES AND RIVER SYSTEM CHANGES OF THE UPPER YELLOW RIVER

Ｉ.ＴｈｅＴｅｒｒａｃｅｓｏｆｔｈｅＵｐｐｅｒＹｅｌｌｏｗＲｉｖｅｒＴｈｅｔｅｒｒａｃｅｓｏｆｔｈｅｕｐｐｅｒＹｅｌｌｏｗＲｉｖｅｒａｒｅｍｏｓｔｌｙｄｉｓｐｅｒｓｅｄａｌｏｎｇｔｈｅｗｉｄｅｒｃｏｕｒｓｅｓｉｎｓｅｖｅｒａｌＭｅｓｏｚｏｉｃＣｅｎｏｚｏｉｃｂａｓｉｎｓ(Ｆｉｇｕｒｅ1).1.ＴｅｒｒａｃｅｓｂｅｔｗｅｅｎＮｇｏｒｉｎｇＬａｋｅａｎｄＧｙａｒｉｎｇＬａｋｅＴｈｅｓｕｒｆａｃｅｌａｙｅｒｓｏｆｔｈｅｓｅｄｉｍｅｎｔｉｎｔｈｅｗｉｄｅａｎｄｓｈａｌｌｏｗｂａｓｉｎｓｗｈｅｒｅｔｈｅＹｅｌｌ…     

THE UTILIZATION OF WATER RESOURCE AND THE OASIS ECONOMIC DEVELOPMENT IN ARID LAND—A CASE STUDY OF TURPAN BASIN

Ｉ.ＩｎｔｒｏｄｕｃｔｉｏｎＩｎｅｘｔｒｅｍｅｌｙａｒｉｄａｒｅａｓｗｈｅｒｅａｒｉｄｉｔｙｉｓｈｉｇｈｅｒｔｈａｎ16.0,ｔｈｅｍａｉｎｔｅｎａｎｃｅａｎｄｄｅｖｅｌｏｐｍｅｎｔｏｆｒｅｇｉｏｎａｌｏａｓｉｓｅｃｏｎｏｍｙｈａｖｅｂｅｅｎｒｅｓｔｒｉｃｔｅｄｂｙｔｈｅｕｔｉｌｉｚａｔｉｏｎａｎｄａｌｌｏｔｍｅｎｔｏｆｗａｔｅｒｒｅｓｏｕｒｃｅ.Ｔｈｕｓ,ｉｔｉｓｓｉｇｎｉｆｉｃａｎｔｌｙｉｍｐｏｒｔａｎｔｔｏｅｘｐｌｏｒｅ,ｏｎｔｈｅｂａｓｉｓｏｆｗａｔｅｒｒｅｓｏｕｒｃｅ,ｔｈｅｄｅｖｅｌｏｐｍｅｎ…     

PELIMINARY ANALYSES FOR CROP WATER CONSUMPTION BY USING LYSIMETER

Ｉ.ＩｎｔｒｏｄｕｃｔｉｏｎＴｈｅＨｕａｎｇ-Ｈｕａｉ-ＨａｉＰｌａｉｎｉｎＮｏｒｔｈＣｈｉｎａｉｓａｃｒｕｃｉａｌａｒｅａｉｎｐｒｏｖｉｄｉｎｇａｂｏｕｔｏｎｅ-ｆｉｆｔｈｏｆｔｏｔａｌｓｔａｔｅｆｏｏｄ[4],ａｎｄｉｔｉｓｆａｃｉｎｇａｓｅｒｉｏｕｓｗａｔｅｒｓｈｏｒｔａｇｅｉｎｒｅｃｅｎｔｙｅａｒｓｄｕｅｔｏｔｈｅｅｘｐａｎｓｉｏｎｏｆｉｎｄｕｓｔｒｙａｎｄａｃｏｎｔｉｎｕｏｕｓｄｅｃｒｅａｓｅｉｎｐｒｅｃｉｐｉｔａｔｉｏｎ.Ｔｈｅｓｔｕｄｙｉｎｓｏｉｌ-ｐｌａｎｔ-ａｔｍｏｓｐｈｅｒｅｃｏｎｔｉ…     

DYNAMIC VARIATIONS OF WATER QUALITY IN TAIHU LAKE AND MULTIVARIATE ANALYSIS OF ITS INFLUENTIAL FACTORS

ＬａｋｅＴａｉｈｕｉｓａｌａｒｇｅｓｈａｌｌｏｗｌａｋｅｉｎＣｈｉｎａ,ｗｈｉｃｈｐａｌｙｓａｎｉｍｐｏｒｔａｎｔｒｏｌｅｉｎｗａｔｅｒ-ｑｕａｎｔｉｔｙｒｅｇｕｌａｔｉｏｎ,ｗａｔｅｒｓｕｐｐｌｙ,ｃｕｌｔｉｖａｔｉｏｎｅｔｃ.Ｗｉｔｈｒａｐｉｄｄｅｖｅｌｏｐｍｅｎｔｏｆａｇｒｉｃｕｌｔｕｒｅａｎｄｉｎｄｕｓｔｒｙｉｎｔｈｅａｒｅａ,ａｌａｒｇｅｎｕｍｂｅｒｏｆｐｏｌｌｕｔａｎｔｓｈａｖｅｂｅｅｎｄｉｓｃｈａｒｇｅｄｉｎｔｏｔｈｅｌａｋｅ,ｌｅａｄｉｎｇｔｏａｎｉｎｃｒｅａｓｅｉｎｎｕｔｒｉｅｎｔｓ…     

Water-quality trends in White Rock Creek Basin from 1912-1994 identified using sediment cores from White Rock Lake reservoir, Dallas, Texas

Historical trends in selected water-quality variables from 1912 to 1994 in White Rock Creek Basin were identified by dated sediment cores from White Rock Lake. White Rock Lake is a 4.4-km² reservoir filled in 1912 and located on the north side of Dallas, Texas, with a drainage area of 259 km². Agriculture dominated land use in White Rock Creek Basin before about 1950. By 1990, 72% of the basin was urban. Sediment cores were dated using cesium-137 and core lithology. Major element concentrations changed, and sedimentation rates and percentage of clay-sized particles in sediments decreased beginning in about 1952 in response to the change in land use. Lead concentrations, normalized with respect to aluminum, were six times larger in sediment deposited in about 1978 than in pre-1952 sediment. Following the introduction of unleaded gasoline in the 1970s, normalized lead concentrations in sediment declined and stabilized at about two and one-half times the pre-1952 level. Normalized zinc and arsenic concentrations increased 66 and 76%, respectively, from before 1952 to 1994. No organochlorine compounds were detected in sediments deposited prior to about 1940. Concentrations of polychlorinated biphenyls (PCB) and DDE (a metabolite of DDT) increased rapidly beginning in the 1940s and peaked in the 1960s at 21 and 20 µg kg^-1, respectively, which is coincident with their peak use in the United States. Concentrations of both declined about an order of magnitude from the 1960s to the 1990s to 3.0 and 2.0 µg kg^-1, respectively. Chlordane and dieldrin concentrations increased during the 1970s and 1980s. The largest chlordane concentration was 8.0 µg kg^-1 and occurred in a sediment sample deposited in about 1990. The largest dieldrin concentration was 0.7 µg kg^-1 and occurred in the most recent sample deposited in the early 1990s. Agricultural use of chlordane and dieldrin was restricted in the 1970s; however, both were used as termiticides, and urban use of chlordane continued at least until 1990. Recent use of dieldrin and aldrin, which degrades to dieldrin, has not been reported; however, increasing trends in dieldrin since the 1970s suggest recent urban use could have occurred.     

Using rainfall-runoff modeling to interpret lake level data

Using water balance computations, the behavior of different kinds of lakes is discussed. Simple analytical expressions relating water level to hydrological conditions and lake bathymetry are given. The importance of knowing the river basin area when analyzing lake levels is stressed. A conceptual rainfall-runoff model including lake routing is used to simulate runoff and lake levels and to compute quasi-steady state conditions and long-term transient situations. It is suggested that models can be used to construct curves relating lake levels to precipitation and lake evaporation. By comparing with paleo-lake levels, the annual precipitation related to these levels can be found, provided information is available about the seasonal distribution of the precipitation.