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191.
通过对安徽省沙坪沟钼矿床矿石物质成分及结构、构造的分析,发现矿石中辉钼矿常呈细小鳞片状、浸染状分布于细脉中。针对岩芯易沿含矿裂纹破裂造成鳞片状辉钼矿丢失,本矿区全部采用金刚石刀具切割分取岩芯。制样过程试验中将样品无缩分粗碎、中碎至<-1.0mm,进行了K值试验,取0.5。缩分后密封棒磨6小时(充分混匀、磨碎)至-200目。分析了该矿区伴生元素不干扰测定的情况,不加Fe2O3载体,刚玉坩埚-Na2O2熔矿,降低空白值,严格质量监控,采用硫氰酸盐分光光度法测定钼量,获得的结果稳定可靠。本试验成果可为从事同类型大型钼矿的分析测试和质量监控提供参考。  相似文献   
192.
长江中下游地区铜矿体综合找矿模型   总被引:1,自引:0,他引:1  
本文在收集研究长江中下游地区主要铜矿床的发现和勘查过程、矿床地质特征、物化探异常特征、勘查方法等大量资料的基础上,对矿体特征进行了归纳,提出了将长江中下游主要铜矿体划分为二型四式的矿体类型划分方案。分别建立了四种类型铜矿体的找矿模型,并建立了铜矿体综合找矿模型。  相似文献   
193.
不同容重的泥石流淤积厚度计算方法研究   总被引:5,自引:0,他引:5  
泥石流的淤积厚度是泥石流灾害评估和防治的最重要的参数之一,但迄今还没有较好的方法计算不同容重的泥石流淤积厚度。本文通过研究泥石流屈服应力的特点,提出了用地区参数和泥石流体积浓度来计算泥石流屈服应力,进而计算泥石流淤积厚度的方法。采用本文方法计算已发生泥石流地区不同容重泥石流的淤积厚度,可以很好地应用于泥石流灾害评估和防治。  相似文献   
194.
废水稳定塘底泥蓄积规律的分析   总被引:2,自引:0,他引:2  
范晓军  钱易 《环境科学》1992,13(4):24-26
通过对底泥来源及组成的分析,认为底泥由可生物降解和不可生物降解两部分组成,并对每部分的蓄积规律及影响因素进行了分析研究,在此基础上建立了稳定塘底泥蓄积公式。根据该公式可得出:①底泥中不可生物降解部分的蓄积与塘运行时间成正比;②可生物降解部分的蓄积存在一个极限值;⑨塘底泥的蓄积与进水水质、水量及塘的运行状况密切相关,同时还受温度的影响。  相似文献   
195.
This work aims to characterize and develop a disposal method for a gel-like deposit generated in a vacuum foreline of an atomic layer deposition (ALD) tool that is using hexachlorodisilane (Si2Cl6, HCDS) as a precursor. This ALD foreline gel was reproduced by replicating the ALD tool process conditions by using a benchtop system that was a 1/85 scale down of one user's process. All samples were tested for shock sensitivity using the Fall hammer apparatus. Extensive infrared studies were done for unhydrolyzed and hydrolyzed gel. Dissolution tests were conducted to develop a method for removing and disposing the gel off-site. Many different solutions such as solvent based solutions, water based alkaline solutions and alcohol based alkaline solutions were tested. It was found that alcohol based alkaline solutions produced only hydrogen as a byproduct and were considered satisfactory for off-site abatement of gel. Furthermore, in-situ cleaning gel of the foreline using a fluorine/N2 mixture with a concentration of 1–10vol% was done. They were all effective in cleaning/removing the gel under the condition of ambient temperature and reduced pressure. Finally, recommended procedures were given for removing as well as disposing the ALD gel.  相似文献   
196.
以纳米金修饰玻碳电极为基础电极,以双酚A为模板分子,以邻氨基苯硫酚为聚合单体,采用循环伏安法电聚合制备分子印迹聚合膜,利用循环伏安和交流阻抗法研究电极的电化学特性。结果表明,双酚A在修饰电极表面的反应是一个受吸附控制的等电子、质子转移的不可逆反应。采用差分脉冲伏安法检测双酚A,线性范围为5. 0×10~(-6)mol/L~4. 0×10~(-4)mol/L,检出限为2. 3×10~(-7)mol/L。将该电极用于自来水和牛奶样品的测定,结果均为未检出,加标回收率分别为93. 5%和95. 4%,3次测定结果的RSD分别为4. 0%和5. 7%。  相似文献   
197.
As a result of Structural Adjustment Programme from the 1980s, many developing countries have experienced an increase in resource extraction activities by international and transnational corporations. The work reported here examines the perceived impacts of gold mining at the community level in the Wassa West District of Ghana, Africa and discusses those perceived impacts in the context of globalization processes and growing multinational corporate interest in Corporate Social Responsibility (CSR). Interview data compared community members' perceptions with those of company representatives in three communities. The results indicate that communities held companies responsible for a series of economic, social, and environmental changes. While recognizing some of the benefits brought by the mines, communities felt that the companies did not live up to their responsibility to support local development. Companies responded by denying, dismissing concerns, or shifting blame. Findings from this work show that lack of engagement and action by government agencies at all levels resulted in companies acting in a surrogate governmental capacity. In such situations, managing expectations is key to community-company relations.  相似文献   
198.
钻井水溶开采地面沉降的机理分析与控制对策措施研究   总被引:1,自引:0,他引:1  
本文通过对某矿钻井水溶开采的溶腔稳定性、覆岩稳定性和地表移动变形分析计算,探讨了该矿产生溶腔失稳和地面沉降的机理,并提出了控制溶腔失稳和地面沉降的对策措施,对钻井水溶开采矿山有一定的借鉴价值。  相似文献   
199.
根据固定床颗粒层内气流含尘浓度的连续方程、颗粒层过滤规律和新型颗粒层的过滤特点,建立了固定床颗粒层过滤过程和新型颗粒层过滤性能的宏观数学模型;根据颗粒层的过滤机理和实际灰尘颗粒粒径的分布状态,在实验的基础上,修正了过滤速度对颗粒层过滤效率的影响;根据实验结果对过滤效率方程式、床层压降方程式中的特征参数进行了回归,得到了具体过滤介质的颗粒层宏观过滤数学模型。模型表明新型颗粒层过滤过程是一个不随过滤时间变化的准稳态过程,只与过滤介质特性和循环清灰周期有关,模型计算值能准确地反映颗粒层的过滤性能。  相似文献   
200.
The novel “Palette Modular Device” (PMD) technology, addressing the recovery of wastes from Physical Vapour Deposition (PVD) maintenance, is evaluated according to a Life Cycle Assessent (LCA) approach. The PMD recovery technology was recently developed with the aim of an easier and more sustainable separation of the film layers used in PVD, with a particular emphasis on multi-material film productions, frequently adopted in the electronic industry. The PMD is briefly presented in the paper, along with three implementations for industrial purposes. Each implementation adopts a different light solvent for the metal recovery like acetone and formic acid. The usage of light solvents is a peculiar feature enabled by the system considered, as an alternative to traditional approaches. The LCA starts with the objectives and prosecutes with inventories of all material and energy flows for each different scenario considered. Additionally, a global impact assessment is provided in a specific section, in order to enable a quantitative comparison of the potential effects on the environment in every scenario. The results of this study allow the industrial designer to perform an overall environmental evaluation of the three strategies proposed and to compare the performances of the novel technology. The research, furthermore, highlights some critical points in the adoption of the PMD and suggests how to improve the implementation of this recovery process.  相似文献   
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