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171.
This study takes cognizance of the fact that the TIOMIN (TIOMIN Resources Inc. of Canada) project has resulted in controversy over its handling of environmental issues and especially the Environmental Impact Assessment (EIA). The authors address many of the protracted issues that have slowed the development of the mining project in Kwale. The main emphasis is on the impacts of the mining and mineral separation processes on the environment, including the governing legislation, the role of consultation and public participation, and socioeconomic issues. In their public documents TIOMIN has specified neither the type of minerals it wants to extract from the area nor their chemical composition. It is well known, however that the titanium minerals and zircon targeted have impurities of iron, thorium and uranium. In the absence of an Environmental Management Plan, the effects of stockpiling radioactive wastes and other impurities that could possibly lead to environmental degradation in both the terrestrial and marine environments have not been publically addressed. The measures proposed to mitigate ecological damage as a result of the establishment of a minerals processing plant in the area seem inadequate. Pollution resulting from accidental spillage or breakage could have significant impact on marine life and residents living near the mining site. Other issues that have not been addressed satisfactorily pertain to the use of surface and underground water. The area already faces a huge water deficit and the calculations presented on aquifer recharge and stream flow rates do not indicate the large quantities of water that would be required in the mineral processing plant. The project, if approved in its present state, risks violation of international conventions. Furthermore, it could cause a conflict between Kenya and Tanzania in the event of an oil spill at the proposed ship loading facility at Shimoni. The proposed mining area includes the district's most fertile land, is home to many fisherfolk and is a major tourist destination. An analysis of the effects of this project on other available opportunities must be thoroughly understood to ascertain the economic and environmental benefits and costs of the mining venture. The proposed compensation rate of $1,000 per acre, for resettlement for example, appears to be grossly inadequate. Compensation should take into account family size and structure family assets and the cost of relocation.  相似文献   
172.
甘肃省岷县章(哈寨)—包(家沟)金矿矿石样品化学分析测试结果,经多次内检发现部分样品Au的分析结果误差较大,推测样品中可能有较大颗粒明金存在。为此,采用简易人工重砂方法对矿区两种类型金矿石进行了矿物分离,再分别进行含金性研究,找出样品分析化验结果跳跃误差的原因,探求更为适宜的分析测试方法。  相似文献   
173.
Kaolin, cordierite, and calcite are investigated as supports for TiO2. The prepared TiO2/support samples are examined for the removal of organic dyes from wastewater. The samples are preliminarily investigated to identify the optimal loaded system using synthetic wastewater containing methylene blue (MB). Data indicate that the investigated support significantly affects the photocatalytic activity of the supported TiO2. Low photocatalytic activity toward MB degradation is observed upon using TiO2/calcite when compared to the unsupported TiO2. Interaction between calcite and titania species probably occurrs to produce the less photoactive CaTiO3 amorphous species. Anatase TiO2 is obtained upon using kaolin and cordierite as supports. The low photocatalytic performance of the TiO2/kaolin sample is also observed. A high concentration of MB on TiO2/kaolin surfaces blocks the photoactive sites. TiO2/cordierite shows the highest photocatalytic activity compared to the unsupported TiO2 as well as the other TiO2/support samples. Rigid cordierite particles suppress the agglomeration of TiO2 particles during the preparation, leading to a high exposed surface of TiO2 towards light illumination. TiO2/cordierite is investigated for the removal of organic dye from real wastewater collected from a textile dyeing factory. Color removal of up to 46% is achieved upon UV irradiation.  相似文献   
174.
榴辉岩型钛矿化的地球化学制约   总被引:1,自引:0,他引:1  
根据对国内外已发表的榴辉岩地球化学资料的统计分析,表明榴辉岩中TiO2含量与全铁(TFeO)具正相关性,而与MgO, 特别是MgO/(MgO TFeO)比值具负相关性.按TiO2含量的高低,可将榴辉岩区分为高钛型(TiO2>2.0%)、中钛型(TiO2=0.60%~2.00%)和低钛型(TiO2<0.6%)三类,文章重点讨论了高钛与低钛榴辉岩地球化学特征的差异.与低钛型榴辉岩相比,高钛型榴辉岩相对偏基性,富铁,贫镁,并具有较高的高场强元素(如Nb、Ta、Zr、Hf等)和亲铁元素(如V、Co、Ni等)含量.原岩恢复显示低钛榴辉岩的源岩有两种类型,其一为洋壳俯冲形成的蛇绿岩残片,另一为富钙质的沉积泥灰岩.高钛型榴辉岩的源岩则具OIB特征,可能为富集地幔部分熔融或上涌的软流圈地幔物质与地壳物质混染的产物.榴辉岩中的钛矿化主要受源岩因素制约,此外,岩浆结晶分异对其也有一定影响.  相似文献   
175.
酒钢1#高炉于1990年3月12日在生产过程中突然发生坍塌,造成国内外冶金史上罕见的高炉生产特大事故。坍塌后对炉缸、炉底风口下沿粘土残砖、炉缸中部环碳砖、炉底高铝砖缝中渗结物等进行了分析,初步查明上述炉料中含有较多的碱金属氧化物K2O、Na2O及锌等有害元素是造成炉缸内粘土砖破损和碳砖产生环形裂缝的主要原因。1 物相组成1-1 化学成分分别从炉缸、炉底采取试样进行化学分析,结果列于表1。表1 试样化学成分(%)Table1 Chemicalcompositionofsamples(%)样品号Si…  相似文献   
176.
混合胶束对钛—溴邻苯三酚红显色体系的增敏作用   总被引:2,自引:0,他引:2  
罗宗铭  梁亮 《岩矿测试》1999,20(2):157-159
在5.0×10-3mol/LH2SO4介质中,溴化十六烷基吡啶(CPB)和OP存在下,Ti(Ⅳ)与溴邻苯三酚红(BPR)形成红紫色络合物。该络合物的λmax=638nm,ε为5.81×104L·mol-1·cm-1,钛的质量浓度为0~0.32mg/L时符合比尔定律。拟定的方法用于硅酸盐岩石中微量钛的测定,结果与原结果相符,RSD(n=6)<1.50%。  相似文献   
177.
原子吸收分光光度法测定锌精矿中锌   总被引:3,自引:0,他引:3  
选择Zn的非灵敏线,采用原子吸收分光光度法测定锌精矿中高含量锌。共存离子互不干扰,平均回收率为99.82%,对于锌精矿测定5次,其RSD〈0.5%,该法所测结果与国家标准分析方法测定的结果相符,且较标准分析方法简便,快速,实用性强。  相似文献   
178.
海水淡化排放的高盐废水对海洋生态环境的影响   总被引:4,自引:0,他引:4  
盐度是海洋环境中最重要的生态因子之一,每种生物各有其适宜生长盐度要求,当环境盐度超过该范围时,生物体的生长、发育、生殖、行为和分布都会受到影响.近10年来,随着淡水资源紧缺和海水淡化处理成本的下降,海水淡化厂数量急剧增加,大量浓盐水进入海区导致受纳海域盐度升高.高浓度盐水给海洋生态环境带来许多负面影响,有关浓盐水的海洋生态安全问题备受人们关注.在总结和分析浓盐水对海洋浮游生物、底栖动物、甲壳类动物、鱼类和海草等影响的基础上,指出海水淡化厂排放的高盐废水对海洋生态的潜在威胁,浓盐水的排放使一些经济水产种类产量减少,给渔业资源和海洋经济带来损失.不同地域环境对海水淡化厂排放水的敏感程度不同,且潮流、海流和水团等水文因素以及海水淡化厂的日处理量和规模等因子决定了排放的高盐废水对海域生态影响的程度.为减少排放的高盐废水对出水口附近海域的影响,提出了海水淡化工程合理规划和布局的可行措施,要选择水体交换良好的海域作为海水淡化工程所在地,对排水口要进行因地制宜地设计,做好高盐废水的再利用工作,以最大限度地减少排放的高盐废水对海区环境的负面影响.建议对海水淡化厂附近海域进行有针对性的水质调查和监测,并做好环境风险影响的评价工作;制定及完善相关的法律法规,建立统一的高盐废水排放标准,而该标准则要以排放的高盐废水对当地海洋生态不造成较大的影响为依据,使海水淡化产业的发展有法可依.  相似文献   
179.
Seasonal and sexual variations as well as the effect of dry feed supplement on total drinking water intake and its utilization were observed in mithun (Bos frontalis)-a semi-wild animal found in North Eastern Hill Region (NEHR) of India. In a completely randomized design, twelve adult mithuns (B. frontalis) as per their sex and body weight were assigned in two different rearing systems (free grazing and free grazing with dry concentrate feed supplementation), and ten growing male mithuns as per their body weight assigned in two different levels of dry concentrate feed supplementation (1.0 kg and 2.0 kg dry concentrate feeds on green forage based diet) and in two different seasons (summer and winter). It was observed that the environmental temperature had a significant effect on drinking water intake by mithuns. Drinking water consumption (per unit of body weight) was significantly (P < 0.05) higher in summer than in winter. Supplementation of concentrate feed on free grazing animals resulted in increase in water consumption. Total water consumption (drinking as well as performed water) was found to be 15.18 litres per 100 kg body weight by growing mithun. Feed dry matter and digestible nutrient intakes by growing mithun were observed to be increased with the increase of supplementation of dry concentrate feed. Roughage to concentrate ratio did not affect the nutrient digestibility. Mithun calves drank an average of 4.30 litres water for each kg of dry matter intake. Metabolic water was significantly (P<0.01) increased with the increase of supplementation of concentrate feed whereas water turn over, which depends upon the body weight of the animals, did not differ significantly on offering of lower or higher level of dry feed. Faecal water loss of growing mithun was decreased with the increase in intake of concentrate feed and was estimated to be 33~46% of total water intake. Excretion of water through faeces of mithun was about 3.8% of body weight. It could, therefore, be inferred that water intake by mithun varied with seasons, rearing systems and dry feed consumption. As far as the water nutrition is concerned, it is needed to give an attention while feeding mithun in summer with dry feed supplementation under semi-intensive system of rearing.  相似文献   
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