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论述了利用金矿冶炼中的酸浸尾渣制取硫酸亚铁溶液,主要考察了温度、反应时间、硫酸浓度、硫酸用量对铁浸出率的影响,得出了酸浸尾渣制取硫酸亚铁的最佳工艺条件。 相似文献
614.
IntroductionOzoneplaysacriticalroleintheearth’secologicalbalanceowingtoitsstrongabsorptionofbiologicallydamagingincomingultra... 相似文献
615.
邱琬钧 《环境监测管理与技术》1997,9(2):44-45
通过条件试验,对改良比浊法测定水中硫酸根方法进行了改进。检测限为0.16mg/L,对地面水,地下水,降水和废水的测定,相对标准差小于1.2%,加标回收率在95.9%-103.8%之间。 相似文献
616.
Jay J. Messer Charles W. Ariss John R. Baker Sevd K. Drous Keith N. Eshleman Andrew J. Kinney W. Scott Overton Michael J. Sale Robert D. Schonbrod 《Journal of the American Water Resources Association》1988,24(4):821-829
ABSTRACT: A pilot study, which was conducted in the Southern Blue Ridge geographical province of the Southeastern U.S., demonstrated the feasibility of a probability-based regional synoptic design for the National Stream Survey, which is a project aimed at estimating the number and percentage of streams in various regions of the U.S. that are acidic or at risk from acid deposition. Estimated population distributions for key chemical variables were not appreciably affected by week-to-week variability in stream chemistry during the spring index period chosen for the study. Differences were observed in estimated acid neutralizing capacity (ANC), nitrate, and pH frequency distributions between spring and summer. Observations made at the downstream node did not represent the chemistry of the entire reach for some variables (ANC and nitrate) as indicated by differences in chemical concentrations between upstream and downstream sampling locations. Coefficients of variation in chemical species were low enough to provide a reasonably stable classification of streams based on ANC. Although median ANC, sulfate, and nitrate concentrations were quite low in the region, the probability of finding streams with ph < 6.3 is less than 1.3 percent at the α= 0.05 confidence level. 相似文献
617.
Environmental impact of two successive chemical treatments in a small shallow eutrophied lake: Part II. Case of copper sulfate 总被引:3,自引:0,他引:3
Van Hullebusch E Deluchat V Chazal PM Baudu M 《Environmental pollution (Barking, Essex : 1987)》2002,120(3):22-634
The appearance of cyanobacteria ( > 10 colony per ml) was not prevented after alum treatment. In order to prevent cyanobacteria efflorescences in a small shallow polymictic lake (Courtille, France), copper sulfate was applied. Treatment level was 63 microg 1(-1) as Cu2+ from CUSO4, 5 H2O. Cyanobacteria were kept under control during the summer. Microcystis sp. completely disappeared, which allowed swimming in the lake throughout the tourist season. Microcystis only reappeared 2 months after the treatment. Copper content in the water column only returned to its background level 2 months after copper addition. This high residence time of copper in the water might have been caused by complexation and adsorption of copper on natural organic matter, whose level was high in the ecosystem studied. A mechanism of transfer of 'truly' dissolved copper towards particulate copper has been underlined and explains the disappearance of this fraction of copper in the water column. 相似文献
618.
新型混凝剂聚硅硫酸铝的研究 总被引:15,自引:0,他引:15
以硫酸铝、水玻璃、铝酸钠为主要原料制备的新型混凝剂聚硅硫酸铝,其产品的Al2O3含量约8%,盐基度40% ̄60%,对制备的PASS溶液经5个月的贮存,其性质稳定,PASS在去浊试验中,无论常温和低温均低优于硫酸铝。对三种工业废水进行混凝处理,取得令人满意的CODcr去除率。 相似文献
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620.
EDTA滴定法测定硫酸盐的检出限确定 总被引:2,自引:0,他引:2
在美国环保总署方法检出限程序的基础上,设计了一个能考虑样品空白和总硬度的可变性对样品测量值贡献的方法检出限程序,并按照此程序对EDTA滴定法测定硫酸盐的检出限进行了确定。对确定结果进行了信噪比和加标回收率检查,证明确定结果能客观地反映实验室对该方法的测试能力。 相似文献