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171.
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
172.
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
173.
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
余斌 《防灾减灾工程学报》2010,30(2):207-211
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
174.
废水稳定塘底泥蓄积规律的分析 总被引:2,自引:0,他引:2
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
175.
Yuan LI Yanqun ZU Qixian FANG Zhaohua GAO Christian SCHVARTZ 《Frontiers of Environmental Science & Engineering》2009,3(3):325-333
This paper studied the relationship between heavy metal concentrations of herbaceous plants and soils at four Pb-Zn mining sites in Yunnan, China. 50 herbaceous plant samples of 9 plant species from 4 families and 50 soil samples were collected and then ana1yzed for the tota1 concentrations of Pb, Cd, and Zn. The results showed that the average concentrations of Pb, Cd, and Zn in soil samples were 3772.83, 168.81, and 5385.65 mg/kg, respectively. The average concentrations of Pb, Cd, and Zn were 395.68, 28.14, and 1664.20 mg/kg in the shoots, and 924.12, 57.25, and 1778.75 mg/kg in the roots, respectively. Heterospecific plants at the same site and conspecific plants at various sites had different average levels of Pb, Cd, and Zn, both in the shoots and the roots. Enrichment coefficients of Pb, Cd, and Zn were greater than 1 in 2, 3, and 9 herbaceous plant samples, respectively. Translocation factors of Pb, Cd, and Zn were greater than 1 in 10, 17, and 25 herbaceous plant samples, respectively. In all 50 samples, the concentrations of Pb, Cd, and Zn between the shoots and the roots, the shoots, and the soils, and the roots and the soils had significant positive relationships. 相似文献
176.
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
177.
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
178.
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
179.
K.M.S. Sundaram 《Journal of environmental science and health. Part. B》2013,48(3):541-579
Abstract Two formulation concentrates of the insecticide, RH‐5992 [N'‐t‐butyl‐N'‐(3,5‐dimethylbenzoyl)‐N‐(4‐ethylbenzoyI) hydrazine], an aqueous flowable (2F) and an emulsion‐suspension (ES), were diluted with water to provide spray mixes containing dosage rates ranging from 35 to 150 g of the active ingredient (AI)/ha. The mixes were sprayed in a laboratory chamber, onto balsam fir branch tips collected from field trees and greenhouse‐grown seedlings. Droplet spectra and spray mass recovery were determined on artificial samplers. Simulated rainfall of two different intensities was applied at different rain‐free periods, and rain droplet sizes were determined. Foliar washoff of RH‐5992 was assessed after application of different amounts of rain, and the increase in soil residues was evaluated. A direct relationship was indicated between the amount of rainfall and RH‐5992 washoff. The larger the rain droplet size, the greater the amount washed off. Longer rain‐free periods made the deposits more resistant to rain. Regardless of the amount of rainfall, rain droplet size and rain‐free period, foliar deposits of the 2F formulation were washed off to a greater extent than the ES formulation. The increase in soil residues due to foliar washoff was greater for the 2F than for the ES formulation. The deposits of the emulsion‐suspension were consistently more resistant to rain‐washing than those of the aqueous flowable formulation. 相似文献
180.