MgCl_2─KCl─H_2O体系相图的测定及其应用

测定了三元体系ＭｇＣｌ２─ＫＣｌ─Ｈ２Ｏ在２８℃与３０℃下的溶解曲线，并在此基础上结合文献中该体系一些温度下的溶解度曲线，对从盐卤提取的ＫＣｌ·ＭｇＣｌ２·６Ｈ２Ｏ复盐中ＫＣｌ的分离，提出一个简便可行的方法。     

电动势法对0、15、35℃时LiCl─Li_2SO_4─H_2O体系中LiCl

电动势法测定水盐体系的平均活度系数是进行热力学性质研究的一个重要方面．近年来，运用Ｐｉｔｚｅｒ离子相互作用模式在更高的浓度和更广的温度范围内来预测水盐体系的溶解度和热力学性质［２，３］．本文是对２５℃时电动势法对ＬｉＣｌ─Ｌｉ２ＳＯ４─Ｈ２Ｏ体系中ＬｉＣｌ的平均活度系数（γ±ＬｉＣｌ）测定［４］的继续和补充。     

NaCl─KCl─MgCl_2─H_2O体系298．15K时稀释热、热容和相对

采用连续滴定量热法测定了四元体系ＮａＣｌ─ＫＣｌ─ＭｇＣｌ２─Ｈ２Ｏ２９８．１５Ｋ时在离子强度为０．１─１２．３９范围内的热容、稀释热和相对表观摩尔焓值，结果表明，随该体系离子强度的减小，其热容值增大，表观摩尔焓值减小，该体系的稀释过程为放热，稀释热的大小取决于稀释起始离子强度与最终离子强度之间的差值。     

酸性溶液中电位法测定理离子

本文在醋酸镁介质中，盐酸溶液形成缓冲溶液后，采用Ｌｉ＋离子选择性膜电极研究了ｐＨ值、ＭｇＣｌ２、ＮａＣｌ和ＫＣｌ对电极响应的影响，得到良好的效果．本法可应用于含ＭＳＣｌ２、ＮａＣｌ和ＫＣｌ的盐酸水溶液体系中锂离子浓度的测定．     

五元交互体系Li^＋,K^＋,Mg^2＋／Cl^—,SO^—4—H2O25℃相关系和溶液物化性质

用等温溶解平衡法研究了Ｌ＾＋，Ｋ＾＋，Ｍｇ＾２＋／Ｃｌ＾－，ＳＯ＾２－４－Ｈ２Ｏ五元交互体系℃的溶解度。该体系相图由十五个盐或复盐的结晶区 构成，饱和溶液的某些物化性质的测定结果与经验公式计算结果吻合，实验测定值与理论预测结果非常一致。     

五元交互体系Li~＋，K~＋，Mg~（2＋）／Cl~－，SO_4~（2－）－H_2O25℃相关系和溶液物化性质的研究

用等温溶解平衡法研究了Ｌｉ＋，Ｋ＋，Ｍｇ（２＋）／Ｃｌ－，—Ｈ２Ｏ五元交互体系２５℃的溶解度。该体系相图由十五个盐或复盐的结晶区构成，饱和溶液的某些物化性质的测定结果与经验公式计算结果吻合，用现代电解质溶液理论—Ｐｉｔｚｅｒ模型预测了该体系的溶解度，实验测定值与理论预测结果非常一致。     

三元体系RECl_3（RE＝Dy，Yb）－HOAc－H_2O（30℃）的研究

测定了三元体系ＲＥＣｌ３（ＲＥ＝Ｄｙ，Ｙｂ）－ＨＯＡｃ－Ｈ２Ｏ（３０℃）的平衡态的溶度数据并绘制了相应的溶度图。在两个体系中分别得到了ＤｙＣｌ３·６Ｈ２Ｏ和ＹｂＣｌ３·６Ｈ２Ｏ两种固相。依据ＨＯＡｃ对ＤｙＣｌ３·６Ｈ２Ｏ和ＹｂＣｌ３·６Ｈ２Ｏ有盐抗作用这一结论得到了一种制备ＤｙＣｌ３·６Ｈ２Ｏ和ＹｂＣｌ３·６Ｈ２Ｏ的ＨＣｌ—ＨＯＡｃ法。同时，在分析测定酸的重量百分浓度时，利用“差减法”得到了Ｈ＋的准确含量。     

东台吉乃尔盐湖卤水的相化学研究（Ⅱ）—冬夏季卤水蒸发实验

为了研究东台吉乃尔盐湖卤水蒸发时的相化学，确定钾、镁和锂盐的结晶特性，在实验室内２５℃等温蒸发实验基础上和自然条件下进行了冬夏季日晒蒸发试验．东台吉乃尔盐湖卤水是由氯化钠饱和的多组分复杂体系构成的．卤水中存在的离子是Ｎａ＋、Ｋ＋、Ｍｇ２＋、Ｌｉ＋、Ｃａ２＋、Ｂ３＋、ＳＯ４２－和Ｃｌ－．试验数据与Ｎａ＋、Ｋ＋、Ｍｇ２＋Ｃｌ－、ＳＯ４２－ＫＨ２Ｏ五元体系介稳平衡数据进行了讨论和比较．Ａｕｔｅｎｒｉｅｔｈ相图被用来表示各数据间的关系和证明冬夏季蒸发时结晶行为的差别．     

盐酸—碱金属氯化物—水三元体系和HCl—LiCl—MgCl2—H2O四元体系热力？…

Ｈ＾＋,Ｌｉ＾＋,Ｍｇ＾２＋／Ｃｌ＾－－Ｈ２Ｏ四元体系０℃,２０℃,４０℃的溶解度预测中需要大量参数,而这些参数的获得,依赖于盐酸－碱金属氯化物－水三元体系和ＨＣｌ－ＬｉＣｌ－ＭｇＣｌ２－Ｈ２Ｏ四元体系的热力学性质。总结了近５０年来国内外对上述体系的热力学性质的研究,为Ｈ＾＋,Ｌｉ＾＋,Ｍｇ＾２＋／Ｃｌ＾－－Ｈ２Ｏ四元体系０℃,２０℃,４０℃的溶解度预测奠定基础,同时为Ｐｉｔｚｅｒ模型增添更合理的     

第四纪察尔汗地区石盐沉积中的氯同位素组成

采用基于Ｃｓ２Ｃｌ＋离子的正热电离质谱高精度测定氯同位素方法（在９５％的置信水平时，测定精度为０．０２％），测定了柴达木盆地察尔汗盐湖ＺＫ─８９０４钻孔原生石盐和次生石盐中氯同位素组成．研究表明五万年以来察尔汗地区氯同位素组成δ３７Ｃｌ的变化范围为－１．１５７～－０．３７９‰（ＳＭＯＣ）．根据氯同位素，组成的变化规律并结合ＺＫ─８９０４钻孔中氢氧同位素组成，推断出在此期间察尔汗盐湖至少经历了三次较大规模的淡化，冰后期和增温干旱期的两次湖水淡化对现代盐湖的形成起到了重要的作用，同时也复证了该地区的古气候演化模式。     

Tracking past mining activity using trace metals,lead isotopes and compositional data analysis of a sediment core from Longemer Lake,Vosges Mountains,France

A 157-cm-long sediment core from Longemer Lake in the Vosges Mountains of France spans the past two millennia and was analyzed for trace metal content and lead isotope composition. Trace metal accumulation rates highlight three main input phases: Roman Times (cal. 100 BC–AD 400), the Middle Ages (cal. AD 1000–1500), and the twentieth century. Atmospheric contamination displays a pattern that is similar to that seen in peat bogs from the region, at least until the eighteenth century. Thereafter, the lake sediment record is more precise than peat records. Some regional mining activity, such as that in archaeologically identified eighteenth-century mining districts, was detected from the lead isotope composition of sediment samples. Compositional data analysis, using six trace metals (silver, arsenic, cadmium, copper, lead and zinc), enabled us to distinguish between background conditions, periods of mining, and of other anthropogenic trace metal emissions, such as the recent use of leaded gasoline.     

吉林省西部草地土壤的化学元素含量及其特征研究

对吉林省西部草地土壤化学元素含量研究表明，吉林省西部草地土壤中富钾少磷；钙、镁含量丰富；硼、铜、铁、锰含量在剖面上表现为向下增加；土壤中氮、磷、钾、钙、铜含量随草地退化程度的加深而减少；土壤中硅、钠含量丰富，显示出较强的沙化、盐碱化趋势，其含量随草地退化程度的加深而增加，钴含量随草地退化程度加深而降低；钡含量随草地退化程度的加深有增加的趋势；而稀土元素总量低于土壤背景值，并随着草地退化程度的加深其含量有减少的趋势。     

基于产业链的全球铜贸易网络结构研究

基于产业链视角研究铜贸易网络,构建了2017年铜矿石、粗铜、精炼铜、铜材和废杂铜5类含铜产品的全球贸易网络,对比产业链上各环节产品的贸易网络的拓扑结构,以全面刻画铜资源的全球流动以及国家(地区)之间的铜贸易关系.主要结论如下:①2001年以来,全球含铜产品贸易重量稳定增长,其中铜矿石贸易重量最大,精炼铜次之.②5类含铜...     

鲤鱼(Cyprinus carpio)鳃部微环境特征与铜的生物有效性

对鲤鱼鳃部微环境进行了定量测量，建立了鲤鱼鳃部微环境的定量模型，对鱼鳃微环境进行了定量描述，通过暴露实验验证了EDTA络合态铜与高岭土颗粒吸附态铜对鱼鳃的生物有效性，并从形态变化的角度分析其存在有效性的原因，即络合态与颗粒吸附态金属随水流经过鱼鳃时，将会部分地发生离解，转变成为可以直接被鱼鳃吸收的形态。     

A multi-element sediment record of hydrological and environmental changes from Lake Erie since 1800

Concentrations of aluminum, arsenic, barium, beryllium, cadmium, calcium, chromium, cobalt, copper, iron, lead, magnesium, manganese, molybdenum, nickel, potassium, selenium, sodium, tin, titanium, vanadium, and zinc were measured in a surface sediment core from the Sandusky basin of Lake Erie to detail the history of hydrological and environmental changes back to 1800. The results from hierarchical cluster and principal component analyses revealed four elemental groups. All the trace elements clustering with aluminum, iron, and manganese in Group I were enriched due to increased inputs from anthropogenic sources. The two conservative elements sodium and potassium clustering in Group II showed patterns of changes like those of water-level fluctuations. The two carbonate elements calcium and magnesium clustering in Group III showed intriguing but complex carbonate biogeochemistry associated with biogenic production, organic acid-induced dissolution and dilution by organic and aluminosilicate materials. The terrigenous element titanium in Group IV experienced two stages of depletion from increased organic fluxes in the 1820s and 1950s. Following the enactments of stringent regulations in the early 1970s, many of these elemental inputs have reduced considerably. But the concurrent reductions in the Sandusky basin were much slower than previously thought. Large increases in inputs from local storages (internal loading) were required to account for the slow reductions. The increased internal loading was caused by augmented organic materials from accelerated eutrophication which facilitated the transfer, transport, and cycling of many trace metals. This work has implications in ongoing research efforts to tackle the eutrophication problem because the complex ecosystem including the internal loading has changed considerably over the past two centuries.     

Recent environmental change and trace metal pollution in World Heritage Bathurst Harbour, southwest Tasmania, Australia

Bathurst Harbour in World Heritage southwest Tasmania, Australia, is one of the world’s most pristine estuarine systems. At present there is a lack of data on pollution impacts or long-term natural variability in the harbor. A ca. 350-year-old ²¹⁰Pb-dated sediment core was analysed for trace metals to track pollution impacts from local and long-range sources. Lead and antimony increased from AD 1870 onwards, which likely reflects remote (i.e. mainland Australian and global) atmospheric pollution sources. Variability in the concentrations of copper and zinc closely followed the history of mining activities in western Tasmania, which began in the AD 1880s. Tin was generally low throughout the core, except for a large peak in AD 1989 ± 0.5 years, which may be a consequence of input from a local small-scale alluvial tin mine. Changes in diatom assemblages were also investigated. The diatom flora was composed mostly of planktonic freshwater and benthic brackish-marine species, consistent with stratified estuarine conditions. Since mining began, however, an overall decrease in the proportion of planktonic to benthic taxa occurred, with the exception of two distinct peaks in the twentieth century that coincided with periods of high rainfall. Despite the region’s remoteness, trace metal analyses revealed evidence of atmospheric pollution from Tasmanian and possibly longer-range mining activities. This, together with recent low rainfall, appears to have contributed to altering the diatom assemblages in one of the most pristine temperate estuaries in the world.     

A 17,300-year record of mercury accumulation in a pristine lake in southern Chile

Anthropogenic mercury accumulation in lake sediments has been studied extensively, but natural processes that controlled mercury accumulation in the past are still poorly understood. We present a 17,300-year record of mercury accumulation in the sediments of Lake Hambre, southernmost Patagonia, Chile (53°S, 70°W), in combination with an investigation of environmental changes in the region. Mercury accumulation in the remote pristine lake varied appreciably, as much as 16×, exceeding the anthropogenic forcing of atmospheric mercury fluxes by a factor of 3–5. Principal Component Analysis revealed that short-term variations were not related to changes in atmospheric mercury deposition or to fluxes of mineral soil into the lake. Instead, there was significant covariation between short-term changes in mercury and catchment-derived trace elements, e.g. copper and yttrium, throughout the past 17,000 years. Covariation between mercury and carbon concentration in some parts of the record suggests that fluxes of particulate and dissolved organic matter from the catchment to the lake account for short-term variations in mercury accumulation. Nevertheless, over the long term, there is no common trend for mercury accumulation and organic matter flux. The median mercury accumulation rate was rather constant (29 μg m^?2 a^?1), whereas the flux of terrestrial organic matter into the lake increased through time. We hypothesize that this was a consequence of a progressive decrease in the input of terrestrial organic matter-bound mercury through time. Whereas production of terrestrial organic matter increased over the long term because of development of catchment vegetation and soils, following glacier retreat, amounts of mercury, copper and yttrium provided by atmospheric deposition and bedrock weathering remained relatively constant. As a consequence, despite increased fluxes of terrestrial organic matter to the lake, fluxes of mercury remained constant.     

三工河流域下游绿洲土壤微量元素有效含量空间变异特征

土壤微量元素空间分布特征是反映特定地区环境状况的一个重要因素。基于GIS技术,通过地统计学方法研究了天山北坡三工河流域冲积平原型绿洲土壤表层微量元素B、Mn、Zn、Fe及Cu等有效含量的空间变异特征。结果表明：①土壤微量元素B、Mn、Zn、Fe和Cu具有强烈的空间自相关性,自相关范围在520～3 970 m内变化,其中Zn和Fe的自相关性尺度相对较大,而B的自相关性尺度最小。②土壤微量元素均具有各向异性,其中在0°方向上变异最大。整体来看,研究区土壤有效B、Fe和Cu具有较强的各向异性,而有效Mn和Zn各向异性相对较弱。③采用Kriging和IDW两种插值方法分析研究区土壤微量元素的空间格局,结果表明,土壤微量元素呈现出明显的片状和斑块状分布特点。研究区中西部有效B含量较高,有效Mn、Zn、Fe和Cu含量均较低。     

AUTOCORRELATION OF TRACE ELEMENT CONTENTS IN SOILS OF TIANJIN PLAIN AREA

Contents0ftraceelementsins0i1sarec0ntr0lledbyb0thinterl1alandcxtcrl1alprocessesoft11eearth,alidtheirspatialdistributi0llpatternsarealsorelatedwit1itlleseprocesses.Thecllaracteristicsofthesepr0cessesareabletoberevea1edbystudyonthespatialdistributiol10ftraceelel11e11tcolltentsinsoils.A11u111be1'o1-methodshavebeenaPpliedtostudythcspatialdistributionoftraceelelnentc0nte11tsinsoils,among'these,geometricalinterpolation,movillgaverage,trendsurfaceanalysisandgeostatisticaltechniquesareoftenused[2,5,7]…