共查询到20条相似文献，搜索用时 109 毫秒
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以国家标准方法和EPA方法为基础, 进行了矿坑排水中苯系物的测定.在测定过程中进行了质量保证和质量控制实验, 用外标法定量.在水样测定的同时对用自动顶空进样器和吹扫捕集浓缩仪两种进样方式测定矿坑排水中苯系物的方法进行了比较, 对进样方式和影响测定的因素进行了讨论.结果表明, 自动顶空进样器的回收率为108.5 8%~116.38%, 方法检出限为5.00~10.00 μg/L; 吹扫捕集浓缩仪的回收率为94.87%~105.6 3%, 方法检出限为0.25~0.50 μg/L. 相似文献
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乐长高 《华东地质学院学报》1999,22(3):260-264
报道了在氢氯化钾的甲醇溶液中,碘氧化２,６－二特丁基－４－甲酚生成稳定的苯氧基化合物Ｉ,并对反应条件进行了研究,实际结果表明,碘氧化２,６－二特丁基－４－甲酚合成１,不仅操作简单,而且产率高达９０％以上。 相似文献
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采用对磺基苯偶氮变色酸分光光度法对岩石样品中氟的含量进行测定。确定的最佳测定条件为:测定波长570 nm,放置2 h后测定,盐酸介质浓度0.84 mol/L,显色剂用量5.0 mL。氟离子浓度在0~1.4 mg/L时符合比尔定律,方法检出限为0.06μg/g。以岩石标准物质代替氟标准溶液制作标准曲线,可有效降低杂质元素的干扰。对国家一级标准物质和日本玄武岩标准物质6次测定的相对标准偏差(RSD)为2.37%~6.32%。 相似文献
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介绍了测定环境水质中６种酚类污染物的气相色谱分析方法。研究了乙醇酐作为酚类衍生化试剂的ＰＨ条件，选择甲苯为萃取剂，比较了大口径毛细管柱和填充柱，氢火焰离子化检测器和电子捕获检测器分离以及测定酚类污染物的精密度和检出限。方法简便，适用于监测地表水和污水中的酚类污染物。 相似文献
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为了研究煤炭固体废弃物中铝的含量及赋存状态,探讨其中氧化铝提取的可能性,在处理煤炭固体废弃物的同时扩大我国自然铝资源,分别采用化学分析、XRD、SEM及粒度分布等方法对鄂尔多斯北缘准格尔等煤田煤矸石及粉煤灰进行了化学成分、物相组成及结构测定。结果表明:该地区的煤矸石和粉煤灰中氧化铝的质量分数均接近或大于40%, 达到了铝矿床的工业品位;煤矸石中铝主要赋存在高岭石和勃姆石中,OF灰中铝主要赋存在莫来石中,而CFB灰中铝则赋存在非晶态物质中;同时CFB灰与OF灰相比具颗粒细小且粒度分布均匀、颗粒形态呈絮状、结构活性高等特点;CFB灰中的铝活性高易提取,煤矸石中的铝只需要热活化即可提取,而OF灰中的铝则需要化学活化才可以提取。高铝煤炭固体废弃物中铝的有效提取可以补充铝资源的不足。 相似文献
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将KHSO4加入在小体积(1mL)试液中,以K2SO4·PbSO4复盐形式沉淀分离Pb,再用NH4Ac溶液热提Pb,1mgPb的平均回收率为100.66%;滤液再蒸至1mL小体积,加入NaCl NaOH小体积两次沉淀分离Fe、Ti、Mn等干扰元素,存在于滤液中的Zn平均回收率为100.5%。分离所得的含Pb2+和Zn2+的溶液用EDTA分别进行滴定,测定范围(质量分数,w)由0.5%下延至0.01%;测定结果与极谱法相一致;精密度(RSD,n=10)试验Pb为2.6%,Zn为1.4%。 相似文献
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低熟煤型气的成因化学 总被引：1，自引：0，他引：1
用水介质热压模拟、１３Ｃｎｍｒ分析表明，Ｒｏ＝０.７%以前，煤型有机质中的芳环结构的变化主要是官能团的变化，芳环仍然保留着单环的结构特征，并未发生明显的缩合作用。即在早期热演化过程中由邻甲氧基苯酚结构向邻苯二酚类结构转化，进而转化为烷基酚类结构，同时脱去甲氧基中的甲基。甲氧基含量从Ｒｏ＜０.３%开始迅速减少，到Ｒｏ＝０.７%时已基本脱除完毕。煤型有机质中的甲氧基在热演化早期通过自由基反应脱去甲基，对低熟煤型气有重要贡献。 相似文献
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The limitations and feasibility of the land disposal of solid wastes containing organic solvents and refrigerants (chlorinated fluorocarbons) were investigated by evaluating the attenuation capacity of a hypothetical waste-disposal site by numerical modeling. The basic theorem of this approach was that the land disposal of wastes would be environmentally acceptable if subsurface attenuation reduced groundwater concentrations of organic compounds to concentrations that were less than health-based, water-quality criteria. Computer simulations indicated that the predicted concentrations of 13 of 33 organic compounds in groundwater would be less than their health-based criteria. Hence, solid wastes containing these compounds could be safely disposed at the site. The attenuation capacity of the site was insufficient to reduce concentrations of four compounds to safe levels without limiting the amount of mass available to leach into groundwater. Threshold masses based on time-dependent migration simulations were estimated for these compounds. The remaining 16 compounds, which consisted mainly of chlorinated hydrocarbons and fluorocarbons could not be safely landfilled without severe restrictions on the amounts disposed. These organic compounds were candidates to ban from land disposal. 相似文献
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Municipal solid waste compost and cattle manure are used as organic fertilizers in agriculture and horticulture. These wastes, however, may also have some negative effects on the agricultural environment. This study investigates the effects of municipal solid waste compost of Kerman (MSC) and cattle manure (CM) on availability of the heavy metal in calcareous soil (extractable with EDTA) in greenhouse conditions. The MSC and CM were mixed thoroughly with soil at rates of 0%, 2%, and 4% of dry matter. After 90 days of incubation, the soil samples were analyzed. Addition of levels of each two organic wastes into soil significantly decreased the soil pH and increased the soil EC as compared with control (unamended soil).The available contents (EDTA-extractable) of Cd, Pb, Cu, Zn, and Cu in the soil samples were increased because of each two organic treatments applied. The heavy metal contents in the soil samples amended with MSC were more than CM. The heavy metal contents of organic wastes were well below the maximum allowed by USEPA. It is recommended that in Iran, the legal maximum permissible limit for heavy elements in organic wastes must be determined. 相似文献
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衍生化气相色谱-质谱法测定复垦土地样品中19种酚类污染物 总被引：2，自引：1，他引：1
近年来国家对自然环境的保护愈加重视,更多被破坏或污染的土地需要进行复垦整治。在评价效果时,需要检测酚类等多项污染物指标。采用气相色谱与气相色谱-质谱联用等方法对酚类化合物直接测定时,存在色谱响应值低、稳定性差、检出限高等问题。本文针对复垦土地样品基质复杂、干扰因素多、前处理困难等特点,对该类样品的提取与净化方法进行筛选优化。根据酚类污染物检测中浓度范围大、重现性差等问题,对衍生化与非衍生化效果进行对比确定了提取和净化方法,结合衍生化条件的优化、实际样品测定结果等方面的综合研究,建立了复垦土地样品19种酚类污染物(其中2,4,6-三氯苯酚和2,4,5-三氯苯酚,以及2,3,4,5-四氯酚和2,3,5,6-四氯酚,因无法分离而合并计算)的衍生化气相色谱-质谱检测方法。该方法采用加速溶剂萃取仪,以正己烷-丙酮(体积比1∶1)提取样品,提取液经浓缩、净化后,由五氟苄基溴衍生化,气相色谱-质谱联用仪测定。该方法基质加标回收率为73.3%~107.0%,检出限为0.67~3.95μg/kg,相比非衍生化方法的检出限(10~80μg/kg)显著降低;并且衍生物的稳定性更好,色谱响应值更高,各组分表现在色谱图上的峰高(峰面积)更均衡,对于低浓度样品的测定结果更加准确。该方法能有效去除基质干扰,可为复杂基质土壤样品中的酚类污染物痕量检测提供参考。 相似文献
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K. R. Duarte C. Justino T. Panteleitchouk A. Zrineh A. C. Freitas A. C. Duarte T. A. P. Rocha-Santos 《International Journal of Environmental Science and Technology》2014,11(3):589-596
This study aims to attempt a treatment strategy based on fungi immobilized on silica-alginate (biocomposites) for removal of phenolic compounds in olive oil mill wastewater (OMW), OMW supplemented (OMWS) with phenolic compounds and water supplemented (WS) with phenolic compounds, thus decreasing its potential impact in the receiving waters. Active (alive) or inactive (death by sterilization) Pleurotus sajor caju was encapsulated in alginate beads. Five beads containing active and inactive fungus were placed in a mold and filled with silica hydrogel (biocomposites). The biocomposites were added to batch reactors containing the OMW, OMWS and WS. The treatment of OMW, OMWS and WS by active and inactive biocomposites was performed throughout 28 days at 25 °C. The efficiency of treatment was evaluated by measuring the removal of targeted organic compounds, chemical oxygen demand (COD) and relative absorbance ratio along the time. Active P. sajor caju biocomposites were able to remove 64.6–88.4 % of phenolic compounds from OMW and OMWS and 91.8–97.5 % in water. Furthermore, in the case of OMW there was also a removal of 30.0–38.1 % of fatty acids, 68.7 % of the sterol and 35 % of COD. The silica–alginate–fungi biocomposites showed a high removal of phenolic compounds from OMW and water. Furthermore, in the application of biocomposites to the treatment of OMW it was observed also a decrease on the concentration of fatty acids and sterols as well as a reduction on the COD. 相似文献
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O. R. A. Sule Dr. 《GeoJournal》1979,3(6):571-577
Proper management of solid wastes is a key to environmental sanitation. In recent times the quality of life in most of the cities of the developing world is being deminished by uncontrolled and poorly managed solid wastes in the urban environment. Lagos urban is a typical example. It must be acknowledged that although wastes from homes, businesses and institutions make up a small part of the total load of solid wastes generated in any urban environment they are certainly the most offensive and most dangerous to health when they accumulate near residential points. The quality of life in urban Lagos, Nigeria, with respect to indiscriminate dumping of uncollected solid wastes approximates an aesthetic disaster. This study is therefore designed to examine the problems of solid wastes disposal in Lagos, Nigeria and to provide data base against which effective solid wastes disposal system in the Nigerian capital city might be monitored and tested.Acknowledgement: I wish to thank members of the Environmental Problems and Effects class (1978/9 Session) Geography Department, University of Calabar for their assistance in collecting data for this study.The Year of the last valid population census in Nigeria. 相似文献
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垃圾填土压缩特性的室内试验研究 总被引：3，自引：1，他引：2
在调查分析了典型生活垃圾填埋场成分组成的基础上,配制了9组具有不同初始物理力学性质的垃圾土,共54个试样,进行室内常规固结试验。试样有两种尺寸,用来对比试样尺寸的影响;着重分析了初始含水量W、初始孔隙比e0及易降解有机物含量B0对垃圾填土压缩性的影响。试样的初始孔隙比变化范围为：e0 为2.5～4.6;初始含水量w的变化为50 %～100 %;易降解有机物含量B0 为10.1 %～45.1 %。分析结果表明,压缩指数Cc为0.824 2～1.234 6;修正压缩指数 为0.165 9～0.243 6,与国内外相似研究的取值基本一致。提出了考虑垃圾填土初始物理参数的压缩参数建议取值方法,为指导工程实践提供参考。 相似文献
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S. Jacob A. D. Chintagunta R. Banerjee 《International Journal of Environmental Science and Technology》2016,13(10):2363-2374
Potato being the staple vegetable in India is widely cultivated and processed for different value additions. During processing of potato, a huge amount of waste is generated in the form of peel and meat (mash). These wastes constitute a potential feedstock for biogas generation. The present study is focused on mitigation of acidogenesis that occurs during early stages of anaerobic digestion (AD) of potato waste which eventually inhibits the process of methanogenesis. A novel strategy of selective digestion was adopted in which the leachate and solid slurry resulting from the first stage digestion were further subjected to second stage by separating the solid and liquid phases. The obtained results indicated that stepwise digestion enhanced biomethane yield with an increase in methane percent from 46.47 to 60.4 % and reduction in total COD to about 94 %. Another novel strategy adopted in this study was the use of specifically developed microbial consortia for AD of potato wastes instead of conventional inoculum for production of biogas. The obtained yield is at par with the conventional inoculums which suggests that the developed consortia could act as potential substitute. The present study paves the way for sustainable utilization of industrial potato wastes for bioenergy production by overcoming the problems associated with conventional processes. 相似文献