铁锰氧化物在污染土壤修复中的作用

矿物学在环境科学中的应用将是21世纪矿物学研究的一个主要方面。土壤污染作为一个制约人类社会可持续发展的基本问题正受到日益广泛的关注，污染土壤的修复已成为环境科学研究的一个重点。污染土壤的修复技术主要有物理、化学、生物等方法，但是，它们都不同程度地存在着缺陷。众所周知，铁和锰是自然界中少数但常见的变价元素。含有变价元素和带有表面电荷的铁锰氧化物具有良好的表面活性，不仅对有毒有害的无机污染物具有良好的净化功能，而且对土壤中有机污染物具有氧化降解作用。利用这些矿物来修复污染土壤，具有成本低、无二次污染等优点，体现出天然净化作用的特色，展现出广阔的环境矿物学应用前景。     

宁芜盆地钟姑矿田典型铁矿成矿岩体Hf-O同位素特征及地质意义

钟姑矿田位于宁芜盆地南部,受矿田内格状构造控制产出一系列早白垩世(129~132Ma)闪长岩及二长岩类侵入体,与铁矿床的形成密切相关,而区域内成矿岩体的研究尤其是岩浆岩的起源和演化有待进一步探讨。本次工作以矿田内的姑山辉石闪长玢岩、龙山辉石闪长岩、白象山闪长岩、钟九闪长岩和太平山二长岩等与铁成矿有关的岩体为研究对象,开展LA-ICP-MS原位锆石Hf同位素和SHRIMP原位O同位素研究。结果显示,钟姑矿田各成矿岩体具有较一致的锆石Hf-O同位素组成,~(176)Hf/~(177)Hf值为0.282425~0.282695,εHf(t)值为-12.3~-3.9,tDM2范围在1.26~1.86Ga;锆石δ18O集中于3.34‰~8.05‰,捕获锆石的176Hf/177Hf比值为0.282324~0.282487,εHf(t)=-15.8~-10.1,锆石tDM2年龄在1.72~20.8Ga之间,锆石δ~(18)O相对集中于5.90‰~6.51‰。钟姑矿田岩浆岩起源于富集的岩石圈地幔,同位素特征指示其携带板块俯冲和蚀变洋壳信息,钟姑矿田的成岩成矿作用应与伸展背景下古太平洋板块俯冲有关。与长江中下游其他矿集区岩浆岩对比研究表明,包括宁芜在内的长江中下游地区岩浆岩具有相同的地幔源区,以铁矿床为主的宁芜和庐枞盆地岩浆岩源区成分以交代岩石圈地幔为主,而以铜陵、繁昌为代表的铜多金属成矿区的岩浆岩受长江中下游新元古代基底的更多影响。     

新疆阿尔泰巴特巴克布拉克铁矿床成矿作用研究

巴特巴克布拉克铁矿床赋存于上志留-下泥盆统康布铁堡组变质火山-沉积岩系中, 近矿围岩为石榴子石矽卡岩、角闪斜长变粒岩和浅粒岩。矿体总体顺层分布, 呈似层状、透镜状及不规则状, 空间上与矽卡岩密切相关。流体包裹体研究表明, 矽卡岩阶段形成的石榴子石中发育纯气体包裹体、气体包裹体、液体包裹体、含子矿物包裹体及熔融包裹体; 退化蚀变阶段发育液体包裹体和少量气体包裹体; 石英-硫化物阶段主要发育液体包裹体、含液体CO₂的三相包裹体及少量纯气体包裹体、气体包裹体和含子矿物包裹体。矽卡岩阶段均一温度变化为217 ℃~499 ℃, 在255 ℃出现峰值, 盐度(NaCl_eq)变化为8.68%~22.65%; 退化蚀变阶段均一温度变化为181 ℃~432 ℃, 在225 ℃出现峰值, 盐度变化为12.85%~22.65%; 石英-硫化物阶段均一温度变化为140 ℃~482 ℃, 在155 ℃出现峰值, 盐度变化为0.18%~42.40%。石榴子石、石英和方解石的 δ¹⁸ O_SMOW 变化为1.8‰~7.1‰, δ¹⁸Ο_Η2Ο为 -4.79‰~4.57‰, δD_SMOW 为 -128‰~-84‰, 表明矽卡岩阶段成矿流体主要为岩浆水, 混合少量大气降水; 石英-硫化物阶段大气降水所占比例明显增加。方解石δ¹³ C_V-PDB 变化为 -3.2‰~-2.0‰, 表明流体中的碳来自深部或地幔。     

The soils on the calcareous sand dunes southeast of South Australia

 The properties of soils on previously dated sand dunes from Robe to Naracoorte in South Australia were examined. In these areas younger sand dunes are composed of fresh sand, but older sand dunes are composed of calcarenited sand. The soils on the sand dunes developed successionally by the age of sand dunes. The soil properties of these sand dunes differ depending on the ages of the sand dunes. The properties of sand particles in soils are as follows: (1) On the sand dunes of 4300 years B.P., A/C profile developed (Rendzina). On the sand dunes older than 125 000 years B.P. and on the plateau of Tertiary limestone, soil profiles of A₁/AB/B/C on the sand dunes of 83 000 years B.P. and A₁/A₃/B₁/B₂/C (Terra rossa) are well developed. (2) Within the sand of A/C horizons of the sand dunes with the age of 4300 year B.P., the calcite grain content is about 64%, and the quartz content is about 35%. Within the B horizons of soils on the dunes from 83 000 years B.P. to 347 000 years B.P., the calcite grain content is only 1–2%; however, the quartz grain content is about 92%. In the B₂ horizons of soils on the dune of 690 000 years B.P. and on the Tertiary plateau, there are some calcite grains but the quartz grain content is about 96%. (3) The average size of quartz grains in the soils on the sand dunes from 4300 B.P. to 347 000 years B.P. is generally smaller, but the average size of quartz on the sand dunes of 690 000 year B.P. becomes larger and the grains are well rounded. On the Tertiary limestone plateau, the average quartz size becomes again smaller, and the grains are more rounded. (4) Fe_t in B₂ horizon of the soil profiles increases clearly corresponding to the age. Iron activity expressed by Fe_o/Fe_d also shows a close relation to the chronological sequence. The B horizon of the soil profiles shows a drastic decrease of Fe_o/Fe_d according to the age. Iron crystalinity, (Fe_d-Fe_o)/Fe_t, has a tendency for a positive relation with increasing age. Received: 1 June 1995 · Accepted: 4 December 1995     

Increasing Iron Concentrations in UK Upland Waters

Iron distributions in rainfall, streams, soils and groundwaters are described for the Upper River Severn catchment of mid-Wales. Iron is mainly supplied from within-catchment sources with highest concentrations occurring under reducing conditions. Iron concentrations have doubled over the past 20 years (~5.0 μg yr⁻¹ for the forest and ~3.7 μg yr⁻¹ for the moorland). For the forested sites, the gradients are particularly high post-1993. UK rivers/lakes monitored by the UK Acid Waters Monitoring Network show similar increases. Generally, Fe correlates with dissolved organic carbon (DOC). The greatest rates of Fe increase coincide with those for DOC. Thermodynamic modelling using WHAM/Model VI indicates that Fe(III) is mainly in microparticulate form (probably oxyhydroxides) apart from under reducing conditions. It is proposed that Fe increases for surface waters are associated with increased microparticulate Fe(III) due to stabilisation against aggregation by binding of DOM to its surface. The results relate to acidification declines and deforestation leading to land disturbance and wetter conditions within the soil. There will be greater acidification reversal following tree harvesting due to lowering of atmospheric SO_x scavenging and this may have resulted in the greater increase in Fe in the later years of the study.     

Shear strength characteristics of Irbid clayey soil mixed with iron filling and iron filling–cement mixture

Iron filling and iron filling–cement mixture were used to improve the shear strength characteristics of Irbid clayey soil. For this purpose, five types of Irbid clay soils were obtained and mixed with iron filling and iron filling–cement mixture at different percentages. Two sets of prepared samples were mixed with the admixture. The first set was prepared by mixing the soil samples with iron filling alone at 2.5, 5.0, 7.5, and 10% by dry weight of the soil. The second set was prepared by mixing with iron filling–cement mixture at equal ratio of the same percentages of the first set. An unconfined compression test was performed in this study to measure the shear strength properties of the soils. The test results showed that the increase in the percentages of the iron filling and iron filling–cement mixture up to 10% will result in increasing the maximum dry density of the soil and increase the unconfined compressive strength and the secant of modulus of elasticity of the clayey soil. Also, the addition of iron filling–cement mixture increased the unconfined compressive strength and secant modulus of elasticity of the clayey soil higher than the addition of iron filling alone.     

川芎嗪对铁过载原代培养脐静脉内皮细胞超氧化物歧化酶、活性氧表达的影响

目的 探讨铁过载对原代培养脐静脉内皮细胞（HUVECS）超氧化物歧化酶（SOD）、活性氧表达的影响及川芎嗪的干预效应。方法 使用酶联免疫法（ELISA）检测体外培养铁过载脐静脉内皮细胞表达的超氧化物歧化酶和活性氧的含量。结果 与空白组比较,模型组超氧化物歧化酶的含量显著降低（P<0.01）,给药组超氧化物歧化酶与模型组比较,差异有统计学意义（P<0.05）;模型组活性氧含量显著高于空白组（P<0.01）,与模型组相比,给药组活性氧含量有明显降低（P<0.05）。结论 川芎嗪能抑制脐静脉内皮细胞铁过载导致的氧化应激,有通过抗氧化应激发挥抗动脉粥样硬化的作用。     

Geochemistry of Archaean volcanic rocks from Iron Ore Supergroup, Singhbhum, eastern India

Mafic-ultramafic rocks of Archaean age constitute a significant component of the Eastern Indian Craton. These occur in two different modes. In the eastern belt these occur as a long, linear enclave within the Singhbhum granite and the primary banding in them is subvertical. In the more extensive western belt along the periphery of the Singhbhum granite, the disposition of the primary banding is subhorizontal. The major rock type in both the belts is meta-basalt with minor peridotitic komatiite and basaltic komatiite occurring in the eastern belt. Rare ultramafic rocks with cumulate textures are present in both the belts. The larger volume of the basaltic rocks preclude the possibility of their being derived by fractional crystallization of the high-MgO components. On the basis of trace element and REE characters the rocks may be classified into three groups. One of the groups shows a tholeiitic trend and include samples mostly from the eastern belt while the second consisting mostly of samples from the western belt shows a calc-alkaline trend. The third group includes samples having elemental ratios intermediate between these two groups. Zr/Nb ratios for the tholeiitic and calc-alkaline samples are different suggesting their sources to be different. The tholeiitic samples have been generated from a source having chondritic REE characters, while the calc-alkaline samples have been generated from a source with LREE enriched character. The high-MgO components in both the groups are suggested to represent high degrees of melting compared to the basalts in each group. It is further suggested that the tholeiitic basalts have been generated relatively early from a chondritic source. Down-buckling of this material has added LREE enriched melts to the source, thereby changing its character into a LREE enriched one. Melting of a source with such changed character has subsequently produced the calc-alkaline melts. Rocks with variable but intermediate characters between these two groups have been generated as a result of contamination between these two groups.     

吉林省板石沟铁矿矿区地质特征

本文认为吉林省板石沟铁矿区为一太古宙绿岩带发育区;铁矿相当于G.A.Gross的阿尔戈马型;矿区鞍山群地层在太古宙末期经历了一次强塑性变形—D_1,它置换了矿区地层,产生了一套透入性的S+F+L构造;这期构造变形发生在低角闪岩相条件下,它控制着板石沟铁矿矿体的形态、厚度、展布及延伸。     

青林省含铁地下水的分布与处理措施

本文根据含铁地下水的形成条件将吉林省含铁地下水划分为四个区,并论述了各区的分布特征。综合国内目前各种地下水除铁技术,着重对各除铁系统的方法、基本原理和适用条件以及经济效益等进行了论述。从环境水文地质学的角度,提出了在含铁地下水区寻找低铁地下水的方法,并通过实例验证是可行的。