有机改性粘土去除赤潮生物的机制研究

研究了季铵化合物改性粘土的制备条件对其去除赤潮藻效果的影响,探讨了该粘土体系高效除藻的机制.实验表明,十六烷基三甲基铵(HDTMA)可以有效地提高粘土的絮凝能力,同时HDTMA改性粘土中含有亚稳态HDTMA,增加了该改性粘土对赤潮生物的灭杀能力.改性粘土去除赤潮藻的能力与所吸附季铵化合物的杀藻能力、吸附量正相关,当老化时间延长、吸附季铵化合物稳定性增强时改性粘土除藻能力大大降低.结构不同的粘土对于吸附HDTMA的稳定化产生的空间阻力不同,在吸附量相同的情况下3层结构的蒙脱土中会有更多的亚稳态HDTMA产生;由于同离子效应,反应介质中高价金属阳离子的存在提高了亚稳态HDTMA的量,因此相应的改性粘土具有更高的赤潮藻去除能力.在60℃条件下吸附的HDTMA会更有效地占据粘土中的阳离子交换位,达到稳定态;而升高或降低温度都会有利于亚稳态HDTMA的出现,相应的改性粘土具有更高的赤潮藻去除能力.     

Decomposition of silicate minerals by Bacillus mucilaginosus in liquid culture

The extraction of K⁺ and SiO₂ from silicate minerals by Bacillus mucilaginosus in liquid culture was studied in incubation experiments. B. mucilaginosus was found to dissolve soil minerals and mica and simultaneously release K⁺ and SiO₂ from the crystal lattices. In contrast, the bacterium did not dissolve feldspar. B. mucilaginosus also produced organic acids and polysaccharides during growth. The polysaccharides strongly adsorbed the organic acids and attached to the surface of the mineral, resulting in an area of high concentration of organic acids near the mineral. The polysaccharides also adsorbed SiO₂ and this affected the equilibrium between the mineral and fluid phases and led to the reaction toward SiO₂ and K⁺ solubilization. These two processes led to the decomposition of silicate minerals by the bacterium.     

2种黏土矿物对磺胺嘧啶的吸附

选择蒙脱土和高岭土2种典型黏土矿物为吸附体, 通过静态吸附试验研究其对磺胺嘧啶的吸附行为,考察温度和pH值对磺胺嘧啶吸附的影响.结果表明,2种黏土矿物对磺胺嘧啶的吸附等温线均能较好地符合Freundlich和Langmuir吸附方程,且Langmuir方程拟合效果优于Freundlich方程;高岭土对磺胺嘧啶的吸附量大于蒙脱土;温度升高和pH值过高或过低均不利于磺胺嘧啶的吸附.     

城市给水厂给水污泥用于烧制粉煤灰-粘土砖的试验

城市给水厂产生的净水污泥(以下简称给水污泥),已成为治理城市固体废弃物污染的紧迫任务,以给水污泥为研究对象,进行了含水率60％-80％的给水污泥-粉煤灰-粘土烧制砖的成型、性能检测等试验研究。结果表明：在给水污泥-粉煤灰-粘土砖中掺人30％-45％(体积比)给水污泥,烧制成品符合国家标准(GB／T 5101-98)要求。     

Concentrations of inorganic elements in bottled waters on the Swedish market

This study presents the concentrations of about 50 metals and ions in 33 different brands of bottled waters on the Swedish market. Ten of the brands showed calcium (Ca) concentrations ≤10 mg L⁻¹ and magnesium (Mg) levels <3 mg L⁻¹, implying very soft waters. Three of these waters had in addition low concentrations of sodium (Na; <7 mg L⁻¹), potassium (K; <3 mg L⁻¹) and bicarbonate (HCO₃ ≤31 mg L⁻¹). These brands were collected from barren districts. Nine of the brands were collected from limestone regions. They showed increased Ca-levels exceeding 50 mg L⁻¹ with a maximum of 289 mg L⁻¹. Corresponding Mg-levels were also raised in two brands exceeding 90 mg L⁻¹. Two soft and carbonated waters were supplemented with Na₂CO₃ and NaCl, resulting in high concentrations of Na (644 and 648 mg L⁻¹) and chloride (Cl; 204 and 219 mg L⁻¹). Such waters may make a substantial contribution to the daily intake of NaCl in high water consumers. The storage of carbonated drinking water in aluminum (Al) cans increased the Al-concentration to about 70 μg L⁻¹. Conclusion As there was a large variation in the material as regards concentrations of macro-elements such as Ca, Mg, Na, K and Cl. Supplementation with salts, e.g., Na₂CO₃, K₂ CO₃ and NaCl, can lead to increased concentrations of Na, K and Cl, as well as decreased ratios of Ca/Na and larger ratios of Na/K. Water with high concentrations of e.g., Ca and Mg, may make a substantial contribution to the daily intake of these elements in high water consumers. Al cans are less suited for storage of carbonated waters, as the lowered pH-values may dissolve Al. The levels of potentially toxic metals in the studied brands were generally low.     

土壤渗滤法治理湿地水环境污染

根据扎龙自然保护区独特的地理、地质条件，研究采用土壤渗滤法处理排入湿地的造纸废水，并从技术和实践分析的角度对该地浅表部亚粘土渗滤的稳定性及可行性进行了探讨。结果表明：保护区地表层的亚粘土对造纸废水中各项污染物均有较好的去除效果，其CODCr、BOD5、Cr^6 、NH4^ -N及TP的去除率分别达到了70％、84％、90％、78％及80％以上，在该处利用缓坡土地渗滤处理系统是稳定可行的。     

新疆赛都糜棱岩型金矿的矿石矿物学特征

本文首次详细论述了赛都糜棱岩型金矿的矿石类型、矿石组构和金属矿物的特征，对金矿物特征和金的赋存状态作了详细描述，并在矿石矿物学分析基础上提出了该金矿的矿化阶段。     

几种粘土矿物对Pb~(2+)的吸附作用及其主要影响因素的探讨

对土壤中常见的三种粘土矿物对Pb2+的吸附作用及其主要影响因素进行了探讨。结果表明，三种粘土矿物对Pb2+的吸附能力顺序为：蒙脱石＞伊利石＞高岭石。蒙脱石对Pb2+的吸附受pH的强烈影响，pH高有利于对Pb2+的吸附。与蒙脱石形成复合体形式的有机化合物的存在不利于蒙脱石对Pb2+的吸附。     

Migration behavior of naturally occurring radionuclides at the Nopal I uranium deposit, Chihuahua, Mexico

Oxidation of pyrite at the Nopal I uranium deposit, Peña Blanca district, Chihuahua, Mexico has resulted in the formation of Fe-oxides/hydroxides. Anomalous U concentrations (i.e. several hundred to several thousand ppm) measured in goethite, hematite, and amorphous Fe-oxyhydroxides in a major fracture that crosscuts the deposit and the absence of U minerals in the fracture suggest that U was retained during secondary mineral growth or sorbed on mineral surfaces. Mobilization and transport of U away from the deposit is suggested by decreasing U concentrations in fracture-infilling materials and in goethite and hematite with distance from the deposit. Greater than unity ²³⁴U/²³⁸U activity ratios measured in fracture-infilling materials indicate relatively recent ( < 1 Ma) U uptake from fluids that carried excess ²³⁴U. Systematic decreases in ²³⁴U/²³⁸U activity ratios of fracture materials with distance from the deposit suggest a multistage mobilization process, such as remobilization of U from ²³⁴U-enriched infill minerals or differential or diminished transport of U-bearing solutions containing excess ²³⁴U.     

阴离子对Acidithiobacillus ferrooxidans氧化活性及次生铁矿物形成影响

酸性矿山废水（AMD）具有酸度高并含有大量可溶性Fe、硫酸根及重（类）金属的特点,采用生物矿化方法促使AMD中Fe向羟基硫酸铁次生矿物转变,对AMD后期石灰中和减少氢氧化铁和废石膏的产生,提高中和效率具有实际意义.通过模拟酸性矿山废水,考察了Cl^-、NO₃^-、PO₄^3-3种阴离子对嗜酸性氧化亚铁硫杆菌（A.ferrooxidans）体系中pH值、Fe²⁺氧化率、总Fe沉淀率、次生铁矿物矿相的影响.结果表明,高浓度阴离子对A.ferrooxidans氧化Fe²⁺能力具有抑制作用.A.ferrooxidans对阴离子的耐受性依次为PO₄^3- > NO₃^- > Cl^-.阴离子浓度在A.ferrooxidans耐受范围内时,其对Fe²⁺的生物氧化速率基本没有影响.但高浓度阴离子会通过抑制A.ferrooxidans的氧化活性,从而间接影响Fe³⁺的水解成矿过程,导致培养终点时总Fe沉淀率降低和次生铁矿物产量减少.受Fe³⁺供应速率降低的影响,次生铁矿物的合成途径易向施氏矿物转变.