安徽铜陵胡村矽卡岩型铜矿水-岩反应动力学实验研究

以铜陵胡村矽卡岩型铜矿为研究对象,选择与成矿关系密切的花岗闪长岩,在22 MPa恒压、不间断流动条件下,与纯水在叠层反应器中进行水-岩反应动力学实验研究。结果表明,水-岩反应速率与流体流速成反相关,与流体在体系内的停顿时间成正相关。铜陵地区Cu,Mo等金属矿化普遍分布于岩体附近可能与此有关。成矿流体中的Cu可能主要是在超临界态流体中迁移,在低于临界态条件下从流体中析出;而在体系温度较低时,主要成矿元素Cu难以从岩石中溶出。在相同温度条件下,Cu,Zn等成矿元素的溶解速率存在较大的差异,可能是导致这些成矿元素在空间上出现分带的原因之一。     

坡缕石对直接耐酸大红4BS的吸附动力学特征

研究了坡缕石对水中直接耐酸大红4BS的吸附动力学,在初始质量浓度为30~50 mg/L,转速为100~200 r/min,以及温度为303~348 K的范围内,坡缕石对直接耐酸大红4BS的吸附动力学数据均符合准二级速率方程。结果表明,坡缕石对直接耐酸大红4BS的吸附是外表面吸附,吸附表观活化能为11.92 kJ/mol,说明此吸附是由液膜扩散控制的物理吸附过程。     

The effect of ductile deformation on the kinetics and mechanisms of the aragonite-calcite transformation

Abstract The effect of ductile deformation (dislocation creep) on the kinetics of the aragonite-calcite transformation has been studied at 1 atm (330° C and 360° C) and 900-1500 MPa (500° C) using undeformed and either previously or simultaneously deformed samples (500° C and a strain rate of 10^-6 s). Deformation enhances the rate of the transformation of calcite to aragonite, but decreases the rate of transformation of aragonite to calcite. The difference results from a dependence of transformation rate on grain size, coupled with a difference in the accommodation mechanisms, climb versus recry-stallization, of these minerals during dislocation creep. Dislocation climb is relatively easy in calcite and thus plastic strain results in high dislocation densities without significant grain size reduction. The rate of transformation to aragonite is enhanced primarily because of the increase in nucleation sites at dislocations and subgrain boundaries. In aragonite, on the other hand, dislocation climb is difficult and thus plastic strain produces extensive dynamic recry-stallization resulting in a substantial grain size reduction. The transformation of aragonite is inhibited because the increase in calcite nucleation sites at dislocations and/or new grain boundaries is more than offset by the inability of calcite to grow across high angle grain boundaries. Thus the net effect of ductile deformation by dislocation creep on the kinetics of polymorphic phase transformations depends on the details of the accommodation mechanism.     

塔中地区奥陶系海相碳酸盐岩储层的溶解动力学特征

选取塔中地区奥陶系海相碳酸盐岩样品进行了模拟实验,以研究其在表生岩溶作用下的溶解动力学特征.实验分别在30,50℃下,用pH值为3～6的盐酸溶液,恒温水浴加热进行.结果表明:4种样品溶解速率的相对大小依次为:灰白色灰岩＞砂屑灰岩＞粗晶白云岩＞中粗-细晶白云岩,且溶解速率均随着温度的升高而增大,随着pH值的增大而减小.但随着外界环境的变化,溶解速率的变化略有差异.造成这种差异的原因可能是样品中的硅酸盐杂质、晶体颗粒的大小以及实验过程中产生的CO2的影响.由实验结果推测可知,对于塔中地区以表生岩溶作用为主形成的奥陶系海相碳酸盐岩储层,灰岩储层的储集性能可能优于白云岩储层;对于以埋藏岩溶作用为主形成的奥陶系海相碳酸盐岩储层,白云岩储层的储集性能可能优于灰岩储层.     

Removal of perchlorate （ClO4^-） contaminants by calcined Zn-Al layered double hydroxides

Layered double hydroxides （LDHs） are a class of synthetic anionic clays whose structure can be described as containing brucite-like layers in which some of the divalent cations have been replaced by trivalent ions, giving rise to positively charged sheets. This charge is balanced by intercalation of anions in the hydrated interlayer regions. LDHs act as sorbents of anionic species through two types of reactions, namely, anion exchange and reconstruction, which further adds the possibility of recycling and reuse. The sorption of anions from aqueous solutions by structural reconstruction of a calcined LDHs is based on a very interesting property of these materials, the so-called memory effect： Calcination of LDHs produces intermediate non-stoichiometric oxides （CLDH） which undergo rehydration in aqueous medium and give back the hydroxide structure with different anions in the interlayers. Perchlorate＇s （ClO4^-） strong oxidizing capabilities make it ideally suited for use as a propellant in solid rocket fuel. However, this use in rocket fuel has led to the ClO4^- contamination of considerable amounts of water throughout the United States. ClO4^- has been shown to inhibit iodide uptake by the thyroid gland; and in large doses, it has been linked to anemia and fetal brain damage. This is especially a problem in China. With the recent emergence of perchlorate contamination as an important drinking water quality issue, adsorption by calcined LDHs was studied for ClO4^- removal. In this work, the effect of various factors such as （a） CLDH structure, （b） conditions for removal of ClO4^- ion, such as dosage of adsorbent, initial concentration of ClO4^-, and temperature and （c） co-existing anions in perchlorate contamination on the removal of ClO4^-, have been investigated, respectively.     

聚羟基铝柱撑蒙脱石吸附重金属离子实验研究

利用keggin离子对蒙脱石进行柱撑制得聚羟基铝柱撑蒙脱石,研究柱撑蒙脱石对Cu^2＋,Cd^2＋,Cr^3＋3种重金属离子的吸附。结果表明：未经焙烧的柱撑蒙脱石对Cu^2＋,Cr^3＋离子的吸附性要比原矿好,而经400℃下焙烧的柱撑蒙脱石对Cd^2＋则有更好的吸附性。用腐殖酸对柱撑蒙脱石改性能提高柱撑蒙脱石对3种重金属离子的吸附性能,柱撑蒙脱石对3种重金属离子的吸附量都随pH值的升高而增加。另外还对柱撑蒙脱石对3种重金属离子的吸附动力学进行了研究．发现其动力学吸附过程可用Elovicb方程和一级动力学方程进行较好的拟合。     

我国下古生界碳酸盐岩烃源岩评价研究现状

碳酸盐岩烃源岩评价对我国油气资源评价与勘探至关重要。本文从有机质成熟度、有机质丰度下限、有机质丰度及生烃潜力的恢复、碳酸盐岩生烃机制与生烃模式等几个方面，介绍了我国碳酸盐岩烃源岩的研究现状，提出了运用生烃动力学对碳酸盐岩烃源岩进行研究的新方法，展望了需要继续关注的问题。     

Modelling ion composition in seepage water from a column experiment with an open cut coal mine sediment

Secondary reactions occurring in pyrite-containing sediments from open cut coal mines are complex and not fully understood. In this study, the changes in seepage water composition in a column experiment with a sediment containing pyrite (5.6 g kg⁻¹) were evaluated using a chemical equilibrium model. A column experiment with artificial irrigation (730 mm water yr⁻¹) was carried out for 2 yr with a sediment from the open pit mine Garzweiler, Germany, at the Institute of Applied Geology. Tracer (LiCl) was added to the sediment. Seepage water composition at 52 cm depth was sampled weekly. Redox potential and the water potential were also recorded weekly. Sulphate and Fe(II) were the dominant ions in the seepage water with concentration maxima of 500 and 350 mmol l⁻¹ after 50 days (0.7 pore volumes (PV)). Minimum pH values were around 0.8 after 100 days (1.4 PV), but increased subsequently and reached 2.4 after 700 days (9.5 PV). Ion activity product calculations indicated the intermediate formation of gypsum (19th–480th day of the experiment). Solutions were undersaturated with respect to alunite, jarosite, jurbanite, schwertmannite, melanterite, gibbsite and goethite during the whole experiment. The model of coupled equilibria which included inorganic complexation, precipitation/dissolution of gypsum and multiple cation exchange was tested. Pyrite oxidation and pH-dependent silicate weathering were considered using simple input functions. Transport was modelled using a field capacity cascade submodel. Model results showed satisfactory agreement with measured values for pH and concentrations of SO₄, Fe, Mg, Ca and Al. Correlation coefficients lay between 0.7 and 0.9 and linear regression coefficients (modelled against measured) were 1.5 (Ca), 1.0 (Fe, SO₄), 0.8 (Mg), 0.7 (pH) and 0.6 (Al). The results showed that the protons produced during pyrite oxidation (94 mmol_c H⁺ kg⁻¹) were mainly released into seepage water (as HSO₄⁻ and H⁺). Cation exchange reactions buffered 20 mmol_c of H⁺ kg⁻¹ sediment, and Al released by silicate weathering accounted for 3.6 mmol_c H⁺ kg⁻¹. Modelling was useful to further understand the significance of different pH buffer reactions.     

H+和有机酸对可变电荷土壤铝释放的动力学研究

利用流动搅动法研究了在模拟酸雨和低分子量有机酸条件下可变电荷土壤铝释放的动力学特征,结果表明,在pH3.5的模拟酸雨作用下,红壤和黄壤中流出液铝的浓度范围约为15～40μmol/L,铝的释放快反应来源于土壤交换性铝和有机络合态铝,铝的释放慢反应对应于含铝矿物的溶解。赤红壤和砖红壤上在0～300min内流出液铝的浓度范围约为1～5μmol/L,流出液pH值大于4.5,对H 的缓冲作用表现为阳离子交换、SO24-的专性吸附释放OH-和矿物表面的质子化;当流出液pH值小于4.5时,H 开始溶解土壤中的含铝固相,铝释放的最后浓度为20～30μmol/L。用相近pH值的有机酸溶出土壤铝的浓度比pH3.5的模拟酸雨要高,特别是在砖红壤上,开始就有大量铝的释放,其浓度为20～75μmol/L,红壤上是70～150μmol/L,随时间延长,流出液中的铝浓度分别为10～20μmol/L和20～30μmol/L。有机酸作用下铝的释放机制主要是有机酸被土壤吸附后,有机酸与位于表面晶格中的铝原子形成络合体,促进了铝的溶解;其次是有机酸的吸附掩盖了土壤表面的质子化过程,增强了酸的溶解,以及有机配体对铝的络合作用,增加了铝的释放量。不同有机酸对铝的溶出能力也有不同,其释放铝能力的大小为:柠檬酸>酒石酸>苹果酸,这取决于有机配体与铝的络合能力。     

用水化学动力学方法分析评价苏锡常地区孔隙Ⅱ承压水超采状态下补给条件的意义

基于孔隙承压水属性,研究了苏锡常地区孔隙Ⅱ承压水超采状态下最大水位埋深期（1994年、1998年）地下水动态（水位、水质）监测资料与水文地质条件。论述水位动态虽能直观反映开采状态下水资源衰竭与水位变化特征,但对补给条件及水动力机制不清楚,则会给超采状态下水文地质条件认识及评价带来视觉上的偏颇。采用水化学动力参数则能很好地反映不同水源补给空间的变化规律,用其常量水化学组分（K+、Na+、Ca2+、Mg2+、Cl-、HCO-3、CO2-3、SO2-4）计算的离子强度（I）、主要离子活度（aHCO-3、aNa+