基于水化学与硫同位素的卡林型金矿区岩溶水文地球化学特征及控制因素

采矿活动通过抽排改变地下水水位和流动条件,促进了地下水与含水层岩石之间的相互作用,同时矿山排水排入地表水系,从而影响整个岩溶水系统的水文地球化学过程.基于水文地球化学和δ³⁴ S同位素,揭示了典型卡林型金矿区及其周边矿山废水、岩溶地下水、地表水等水文地球化学过程、特征及其主要控制因子.结果表明,未受金矿开采活动影响的地下水和地表水的丰、枯水期水化学组分主要受灰岩和白云质灰岩风化作用控制,离子以Ca²⁺、Mg²⁺和HCO₃^-为主,水化学类型均为Ca-HCO₃型.而矿山废水及其下游受纳水体受碳酸盐和硅酸盐矿物溶蚀与离子交换作用影响,离子以Ca²⁺、Mg²⁺、Na⁺和SO₄^2-为主,水化学类型由Ca-HCO₃型逐步演化为Ca-SO₄型.受矿山开采影响的各类水体中SO₄^2-是特征组分,SO₄^2-浓度在井下呈现从上至下逐渐降低的显著规律.未受矿山废水影响的地下水和地表水δ³⁴ S值偏正,SO₄^2-主要来源于雄黄矿的氧化,而矿山废水及其下游受纳水体δ³⁴ S值偏负,SO₄^2-主要受雄黄矿氧化和大气降水两个端元混合作用的影响,黄铁矿也有一定贡献.同时,各类水体的NO₃^-源于农业化肥施用和农村生活污水直排的输入.     

夹皮沟金矿区土壤汞的赋存形态及污染特征

使用改进的BCR连续提取法和电感耦合等离子质谱(ICP-MS),测定夹皮沟金矿区土壤样品中汞元素的赋存形态及含量。结果表明,三个深度的土壤汞元素形态分布趋势相似,均以残渣态为主,其次为可氧化态和可还原态,酸溶/可交换态和水溶态所占比例较少,各形态汞的分配系数依次为:残渣态(48.28%)可氧化态(25.68%)可还原态(13.35%)酸溶/可交换态(8.38%)水溶态(4.33%)。垂直方向上,20~40 cm的中层土壤中的汞含量略高于0~20 cm的表层土壤,40~60 cm的下层土壤则含量最低。不同深度土壤中的有效态汞与总汞的含量具有较高的相关性,但三层土壤不具有相同的相关趋势。     

持续性降水气象条件下土壤/大气间汞通量特征

为研究自然条件下地表大气间汞交换通量特征及其影响因素,2012年4月22~25日在位于松花江上游的夹皮沟金矿,使用动态通量箱法(dynamic flux chamber, DFC)与汞分析仪(LUMEX Zeeman RA915+)联用技术测定了在持续性降雨气象条件控制下矿区土壤大气间汞交换通量,同步测定了近地面垂向0~150cm范围内大气汞浓度以及太阳辐射强度和大气温湿度,并分析了汞交换通量与降水条件下气象因子间相关关系.结果表明:在持续性降雨条件控制下,地表大气间的汞交换通量表现为沉降与释放过程连续交替出现特征,这与晴朗天气条件下日型汞通量单峰结构明显不同.降水间歇期土壤大气间汞交换通量在坡耕农田采样点依次为(-2.08±6.11)、(-6.16±33.57)、(-3.20±8.64)和(5.06±18.80)ng/(m2·h);在谷底漫滩采样点依次为(-5.21±6.42)、(3.87±28.12)、(-11.87±14.10)和(-9.44±12.23)ng/(m2·h).在局地范围内,地形条件差异影响不同地表和近地面大气系统能量收支,并使近地面大气汞浓度和气象因子发生变化,进而影响地表大气间汞交换通量过程和水平.持续性降水条件下,地表和大气间汞交换通量与太阳辐射强度和大气湿度间具有较为明显的正线性相关关系,与大气汞浓度和大气温度间无明显线性相关关系.     

Manufactured silver and gold nanoparticles-induced apoptosis by caspase-pathway in human cell lines

Abstract

Metallic nanoparticles have emerged as an important class of nanomaterials for a wide range of industrial and medical applications. Because of the intensive commercial applications, risk assessment of these nanoparticles is of great importance. In the present study, the human hepatoma and leukemia cells were used to characterize the apoptotic effects of silver nanoparticles (4.7 and 42?nm) and gold nanoparticles (30?nm). Apoptotic cells were identified by chromatin condensation and flow cytometry analysis, using Annexin V/PI, TUNEL and caspase activation assays. Flow cytometry analysis showed that the three metallic nanoparticles induced apoptotic cell death in a concentration and time dependent-manner. Moreover, the three nanoparticles induced activation of caspase-3 and -7 in hepatoma and leukemia cells. Apoptotic effects were stronger after exposure of both cell lines with 4.7?nm silver nanoparticles than those obtained with 42?nm silver and 30?nm gold nanoparticles. In conclusion, silver (4.7 and 42?nm) and gold (30?nm) nanoparticles induced apoptosis in hepatoma and leukemia cells via the caspase dependent pathway. The smaller silver nanoparticles (4.7?nm) had a greater ability to induce apoptosis in both cell lines.     

阜山金矿进回风巷粉尘孔粒径分布及其分形特征

为探究金属矿井下粉尘孔粒径特征,以阜山金矿为例,系统研究其进风巷粉尘(IAD)、回风巷粉尘(RAD)的孔粒径分布(PSD)情况.首先,利用激光粒度分析仪与扫描电子显微镜(SEM)、低温液氮吸附仪分别测试粉尘粒径与孔参数,然后利用分形理论计算并分析其粒度分形维数与孔分形维数.结果 表明:RAD粒径比IAD粒径小,两者最可...     

Catalytic decomposition of low level ozone with gold nanoparticles supported on activated carbon

Highly dispersed gold nanoparticles were supported on coal-based activated carbon (AC) by a sol immobilization method and were used to investigate their catalytic activity for low-level ozone decomposition at ambient temperature. Nitrogen adsorption-desorption, scanning electron microscope (SEM), and X-ray photoelectron spectroscopy (XPS) were used to characterize the catalysts before and after ozone decomposition. The results showed that the supported gold nanoparticles prepared with microwave heating were much smaller and more uniformly dispersed on the activated carbon than those prepared with traditional conduction heating, exhibiting higher catalytic activity for ozone decomposition. The pH values of gold precursor solution significantly influenced the catalytic activity of supported gold for ozone decomposition, and the best pH value was 8. In the case of space velocity of 120000h⁻¹, inlet ozone concentration of 50mg/m³, and relative humidity of 45%, the Au/AC catalyst maintained the ozone removal ratio at 90.7% after 2500min. After being used for ozone decomposition, the surface carbon of the catalyst was partly oxidized and the oxygen content increased accordingly, while its specific surface area and pore volume only decreased a little. Ozone was mainly catalytically decomposed by the gold nanoparticles supported on the activated carbon.     

电解法处理废料贵铅的电极极化研究

以含金银铅废料制成贵铅为原料,利用电化学热力学和动力学理论,对贵铅电解法实现金银与铅的分离和得到纯铅的电极过程极化行为与工艺条件的关系进行了研究。从而确定了贵铅电解时的电解液组成为［ｐｂ２＋］７０ｇ／Ｌ,温度为４０℃,β－萘酚／胶联合添加剂等工艺条件．同时根据动力学的研究证明了贵铅电解的电极反应速度受扩散控制,其扩散速度常数Ｋ扩＝１．９１７×１０－３ｃｍ／ｓ。扩散层厚度为０．００５１ｃｍ,在ηｋ＝７５ｍＶ时的阴极过程活化能为１６．１０ｋＪ／ｍｏｌ,为贵铅电解工业分离回收金银铅提供了可靠的理论依据和设计参数。     

胶东玲珑-焦家式金矿床矿源岩系(序)列研究

在前人研究成果的基础上 ,通过详细分析胶东岩体形成的环境、岩石地球化学成分、同位素、稀土特征以及它们与金矿的关系 ,逐步形成了对金矿床矿源岩系 (序 )列的初步认识 ,将胶东成矿矿源岩系划分为初始矿源岩、中间矿源岩系和直接矿源岩组合 ,并指出其主要找矿意义     

论蓬家夼金矿的地质特征及成因——与聂爱国等商榷

蓬家夼金矿是山东乳山地区新发现的金矿类型 ,受荆山群中的构造角砾岩系控制 ,沿胶莱盆地边缘莱阳组砾岩与荆山群副变质岩的构造接触带分布。矿体严格受滑脱构造控制 ,与荆山群变质杂岩中的大理岩、含石墨岩系关系密切。矿床地球化学特征表明 ,矿质主要来自围岩荆山群地层。认为蓬家夼金矿是在白垩系火山活动期间 ,以大气降水为主的混合水循环系统 ,萃取围岩 (主要是荆山群 )中的成矿物质 ,沿滑脱断层沉淀形成的 ,而不是前人所确定的沉积 -改造作用形成的新类型金矿床。     

新疆阿克提什坎金矿床微量元素特征

阿克提什坎金矿床位于北阿尔泰诺尔特地区南缘东段 ,赋存于下石炭统红山嘴组地层中。系统地研究了该金矿床微量元素的组成特征 ,并应用等位线方法讨论了热液蚀变作用过程中微量元素的行为 ,并对微量元素在热液蚀变过程中迁移的质量进行了计算 ,研究表明在热液蚀变作用过程中 ,微量元素尤其是Au、As等元素活动强烈 ,有较大的带入和带出 ,微量元素尤其是成矿元素表现出随蚀变程度加深变化量加大的特点