Environmentally geochemical characteristics of vanadium in the topsoil in the Panzhihua mining area,Sichuan Province,China

Vanadium is a trace element, which may be biologically beneficial and possibly essential but certainly harmful to human beings and some living organisms if excessive. After over 40 years of development, the mining industry has caused serious environmental problems in the Panzhihua mining area. Vanadium is significantly accu-mulated in the soil of the Panzhihua area. Human activities have intensified the pollution and release of vanadium and caused serious damages to the ecological system there. In the past few years, the authors have made investiga-tions into and assessments on the geochemical distribution, chemical speciation, adsorption characteristics and transfer behavior of vanadium in the topsoil in the Panzhihua mining area. The results showed that: (1) the difference in the contents of vanadium in soil between premonsoon and monsoon is insignificant; (2) the adsorption isotherms of vanadium on soil in the Panzhihua mining area ate well described by the Langmuir type; (3) the transfer ability of vanadium in soil is interrelated to soil properties; and (4) the chemical speciation of vanadium shows an order of insoluble residue > oxidizable=reducible > soluble component. According to the above results, some countermea-sures to control pollution of vanadium in soil should be put forward.     

江西鄱阳湖地区地下水中钒元素的背景特征

根据国家科技攻关项目的研究成果，本文论述了江西鄱阳湖地区地下水中钒元素的背景特征及其分布规律与地下水含水介质成分，氧化还原环境以及酸碱度的关系。     

利用Chelex—100树脂预浓缩管柱测定海水中的钒

由树脂含量、pH、管柱口径与流等浓缩条件的改变,可得到一个以Chelex-100树脂浓缩钒之预测方程式。依此方程式预测结果,与实际回收结果比较发现,若能使用醋酸钠缓冲溶液调配成pH 为4.0左右的海水,利用由太空管所制作而成,含有2g Chelex-100树脂之7.938mm 口径之预浓缩管柱,在海水流经树脂速度不超过5cm~3/min 的流速下,经由海水添加实验,可得到钒回收率的结果为(99±3)%。不过钒与树脂的亲合力不如其他重金属离子,在流速大于6cm~3/min 以上时,因钒与树脂反应不完全,使实测值回收率较预测值低。从实际水样测定结果发现,溶解性钒在南海北部表层海水的质量浓度为1.56μg/dm~3,随深度增加则浓度渐增。海水深度大于500m 时,则钒的浓度不再有明显的变化,浓度介于1.69～1.70μg/dm~3之间,经盐度校正后显示,表层钒有轻度消耗的现象。     

氧化酸性铬蓝K褪色光度法测定钒

在１８０～２５０ｍｏｌ／ＬＨ２ＳＯ４介质中,Ｖ（Ⅴ）对酸性铬蓝Ｋ有褪色作用。褪色程度与Ｖ（Ⅴ）量相关,借此建立了吸光光度测定Ｖ的方法。实验表明,褪色反应随温度升高而加快,在沸水浴中１０ｍｉｎΔＡ可达最大值,流水冷却后吸光度保持２４ｈ不变,有色溶液的最大吸收波长为５２０ｎｍ,ε＝１０×１０４Ｌ·ｍｏｌ－１·ｃｍ－１,Ｖ（Ⅴ）量在０～３２ｍｇ／Ｌ内与有色溶液吸光度的减少值呈线性关系。所拟方法用于测定铁矿石中微量Ｖ时,结果与苯甲酰基苯胲比色法一致。     

水平式ICP—AES测定岩石中痕量铍,铬,锰,钒和锆

用HNO_3—HCLO_4—HF混合酸,加压分解试样,以水平式ICP—AES可同时测定岩石中痕量铍、铬、锰、钒和锆。方法简单、现性好、准确度高。Bc,Cr,Mn,V,Zr的检出限分别为0.0001,0.002,0.002,0.002,0.005mg/ml,变异系数均小于5％。结果令人满意。     

Influences of vanadium compound on burning characteristics of emulsified marine fuel oil C

Vanadium is one of the most significant trace elements in heavy fuel oils. While most previous studies emphasize its effects on the high-temperature corrosion of power-plant materials, the understanding of the basic combustion characteristics influenced by the vanadium content in fuel oils is still rather limited. The influences of the controlling factors, such as water-to-oil ratio, amount of emulsifying agent, and content of vanadium pentoxide on the burning characteristics of marine heavy No.6 fuel oil are thus investigated in this experimental study by using a suspended droplet approach. It is shown that the ignition delay, degree of micro-explosion, burning time, and flame length are affected by those factors to various extents. Increase of the water-to-oil ratio might enhance the micro-explosion phenomenon while the addition of an appropriate amount of the emulsifying agent Span-80 promotes the homogeneity of micro-water-droplets over their oil base, leading to alterations of the heated droplet characteristics of the emulsions. However, the existence of V₂O₅ in a fuel oil would result in deterioration of burning quality.     

Environmental geochemistry and ecological risk of vanadium pollution in Panzhihua mining and smelting area, Sichuan, China

1 Introduction Vanadium (V) is a relatively abundant elemenwhich is widely distributed in nature; howeverworkable V deposits are very rare (World HealthOrganization, 2001). Vanadium is a trace elementwhich may be beneficial and possibly essential fohuman…     

贵州岑巩县注溪钒矿地质特征

本文根据该矿区所获地质勘查成果资料,通过初步综合分析,总结描述了矿区基本地质及矿床地质特征,提出区内划分留茶坡组（Z∈ lc）与九门冲组（∈1jm）分界及钒矿层（体）对比的标志层,对指导该区找矿及勘查工作具有一定意义。     

2—（四氮唑偶氮）—5—二乙氨基苯甲酸的合成及光度法测定钒

研究了新显色剂2 (四氮唑偶氮) 5 二乙氨基苯甲酸(简称TTZDBA)的合成。经元素分析、红外光谱、紫外光谱、核磁共振谱等方法测试确定其组成和结构。研究了试剂的性质及其与钒的显色反应的条件,建立了光度法测定钒的新方法。在pH3.5的HAc NaAc介质中,TTZD BA与V(Ⅴ)形成摩尔比为2∶1的紫红色配合物,配合物至少稳定18h,其最大吸收波长在566nm处,表观摩尔吸光系数为3.52×104L·mol-1·cm-1,V(Ⅴ)质量浓度在0～0.8mg/L内遵守比尔定律。经标样分析验证,结果与标准值相符,加标回收率为101.3%～102.8%,RSD(n=6)在1.0%～2.5%。所拟方法可不经分离直接测定铝合金样品及合成废水中的钒。     

湖南黑色岩系中的钒矿床

湖南沉积型钒矿床主要分布于武陵山区、雪峰山区和湘中龙山地区等。钒矿床赋存于下寒武统底部黑色岩系层位中,以含钒伊利石形式存在,并伴有Ni、Mo、Cu、U多种元素。其成矿作用受雷峰运动后形成的坳陷盆地边缘陆棚沉积环境所控制,其富集与有机质和生物化学成矿有关。