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131.
132.
抗生素废水碱回收与生化处理试验研究 总被引:1,自引:0,他引:1
为克服抗生素废水难以生化处理的难题,采用废碱液回收利用和生物强化处理的技术手段对废水进行了资源化小试研究。结果显示,经碱液回收后出水的COD、SS、硫酸盐和含盐量分别由13 925、45 700、417和29 900 mg/L降到了2 400、86、25和402 mg/L,色度也由6 000倍降到了5倍;经与综合污水混合后生化强化处理,出水COD、色度和硫酸盐的平均去除率分别达到了91%、84%和96.5%,处理效果理想,资源化技术处理废水可盈利54.19元/t,具有较好的经济性,值得推广应用。 相似文献
133.
含铬钻井泥浆固化及影响因素 总被引:3,自引:0,他引:3
固化技术是含铬钻井泥浆无害化处理最有效的方法。以四川西部某钻井泥浆为研究对象,选取水泥、石灰、聚铝和水玻璃作为固化处理剂,运用正交试验研究了含铬钻井泥浆实验条件。最佳试验配方是:先将泥浆含水率调整为46%,水泥、聚铝、石灰和水玻璃的添加量分别为10%、1%、3%和0.5%。固化72 h,该试验配方对六价铬和总铬的固化率分别达到93%和95%,浸出六价铬浓度符合地下水三类水标准(GB/T14848-9),浸出总铬浓度符合国家污水综合排放标准(GB5085.3-1996)。 相似文献
134.
Previous studies of upland roadside soils in Cumbria, that would normally be naturally acidic, have highlighted that (a) runoff from roads subjected to long-term road salting can dramatically raise soil pH down slope in upland areas; (b) the soil pH increase dramatically changes N cycling in soils down slope, increasing mineralisation of organic matter, ammonification, ammonium leaching down slope and nitrification and nitrate leaching; (c) the increase in nitrification substantially increases nitrate leaching to down-slope rivers, and this is readily detectable in field studies; and (d) loss of soil organic matter over decades of salting is so great that organic matter is no longer substantially solubilised by high salt concentrations found in soil solution below road drains. This paper tests and supports the hypothesis that such effects are minimal for more calcareous soil ecosystems. It examines the soil and soil solution chemistry on another Cumbrian upland highway, the A686 near Leadgate, Alston. Sodium % of soil CEC values for soil transects affected by spray containing road salt are similar at both the A6 and A686 sites. However, spatial trends in calcium, magnesium, ammonium, and nitrate concentrations as well as pH differ, as a direct result of the higher weathering rate of parent material and possibly also the presence of limestone walls above both spray-affected and control transects at the A686 site. 相似文献
135.
136.
AbstractAndrographolide sodium bisulfite (ASB) widely used for intestinal infections and respiratory tract infections. It has been reported to frequently cause acute renal failure in clinical practice. The purpose of this study was to evaluate the nephrotoxicity and toxicokinetics in Sprague-Dawley rats after a single-dose injection of ASB administered at 100, 600, and 1000?mg/kg via intravenous tail injections. The concentrations in plasma and kidney microdialysates were analyzed by high-performance liquid chromatography. Blood urea nitrogen and creatinine levels in plasma were determined and toxicokinetic parameters were observed. In plasma and kidney, the elimination constant and clearance were decreased and the half-time was increased with increasing dose. Blood urea nitrogen and creatinine were positively correlated with ASB concentration indicating the potential for accumulation in kidney that can eventually lead to damage. 相似文献
137.
以乙醇为溶析剂,通过过滤—中和—蒸馏浓缩—溶析结晶等工序,从白炭黑废母液中回收硫酸钠。考察了硫酸钠回收效果的影响因素,并进行了热能消耗和处理成本的分析。实验结果表明:乙醇的加入量对硫酸钠溶解度和蒸馏浓缩过程有着显著影响;在蒸馏醇水比(乙醇与中性废母液的体积比)为0.27,浓缩废母液中硫酸钠质量浓度为69.27 g/L,溶析醇水比(乙醇与浓缩废母液的体积比)为1的最佳工艺条件下,白炭黑废母液中硫酸钠的一次回收率可达69.94%,硫酸钠产品的纯度达到97.3%。 相似文献
138.
Najam Akhtar Shakil Jitendra Kumar Pankaj Alka Pandey Vivek Ahluwalia Manish K. Singh 《Journal of environmental science and health. Part. B》2013,48(4):344-349
A series of novel N-alkyl-N-[1-(2-hydroxyphenyl) ethyl]amines were synthesized as potential new agents to control pests. Their structures were confirmed on the basis of IR, NMR and elemental analyses. Six new N-alkyl-N-[1-(2-hydroxyphenyl) ethyl]amines were prepared by reduction of corresponding Schiff bases using sodium borohydride in 80–87 % yields. These compounds were tested for their antifungal activity against two pathogenic fungi viz., Rhizoctonia bataticola ITCC 0482 and Sclerotium rolfsii ITCC 5226 and for insecticidal activity against insects of stored grain pest Callosobruchus analis. Fungicidal bioassay revealed that compound N-Decyl-N-[1-(2-hydroxyphenyl)ethyl]amine, was highly effective against R. bataticola (ED50 6.86 mg L?1) which was comparable with that of commercial fungicide hexaconazole (ED50 6.35 mg L?1). Also compounds N-Heptyl-N-[1-(2-hydroxyphenyl)ethyl]amine, N-Octyl-N-[1-(2-hydroxyphenyl)ethyl]amine and N-Nonyl-N-[1-(2-hydroxyphenyl)ethyl]amine displayed promising fungitoxicity against same pathogen. However, compound N-Heptyl-N-[1-(2-hydroxyphenyl)ethyl]amine was also found to be effective against S. rolfsii (ED50 4.92 mg L?1 as against 1.27 mg L?1 for hexaconazole). Compound N-Hexyl-N-[1-(2-hydroxyphenyl)ethyl]amine was most effective as insecticide followed by compound N-Octyl-N-[1-(2-hydroxyphenyl)ethyl]amine. LC50 values for these compounds were 155.0 and 275.0 mg L?1 respectively as against 36.70 mg L?1 for commercial insecticide dichlorovos. The results obtained from bioassays indicate that this class of compounds can be utilized for the design of new substances endowed with pesticidal activities. 相似文献
139.
Thushara Kandaramath Hari Zahira Yaakob 《International Journal of Green Energy》2017,14(14):1163-1171
Influence of catalyst calcination temperature on the catalyst characteristics and catalytic transesterification of Jatropha curcas oil for biodiesel production was studied by using sodium zirconate (Na2ZrO3) solid base catalyst. Na2ZrO3 catalysts were prepared by impregnation method followed by calcination at temperatures of 700, 800, and 900°C. The prepared catalysts were characterized by X-ray diffraction analysis, Fourier transform infrared spectroscopy, and field emission scanning electron microscopy. Important parameters influencing the catalytic activity and fatty acid methyl ester yield were investigated. It was found that the increase in calcination temperature showed marked increase in activity due to the increased porosity and presence of tetragonal zirconia. Investigation of the reusability of the catalysts showed that the catalytic activity was retained even after five cycles of reaction. 相似文献
140.