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961.
国内外许多重大工业事故的发生都与危险设施不合理的土地利用规划相关.尽管相关法规对于危险设施的安全规划提出要求,但目前我国针对危险设施安全规划方法仍非常缺乏.本文介绍的危险设施土地利用规划方法简便、易行.该方法可以根据考虑危险物质种类、数量和形态、危险设施的厂区布置情况和危险物质生产方式等条件,可对危险设施的土地安全适用性进行判断,为规划许可提供参考. 相似文献
962.
从稠油罐底泥中回收矿物油 总被引:3,自引:0,他引:3
为了回收稠油罐底泥(简称油泥)中的矿物油并提高油泥焚烧系统的处理能力,分析了辽河油泥的特点,对比传统油泥处理方法的优劣,提出了溶剂萃取-离心分离-稠油热废水洗涤-离心分离技术回收矿物油的工艺路线。实验结果表明:该工艺可回收92.07%的矿物油和56.85%的热能;残渣中矿物油的质量分数小于等于2.00%,热值大于等于5000kJ/kg,不需添加辅助燃料即可焚烧处理。 相似文献
963.
采用静态吸附法研究了聚丙烯酰胺(PAM)在大庆市盐碱土中的吸附行为,并通过室内土柱实验研究了PAM在盐碱土中的自然迁移和模拟降雨情况下的迁移行为。实验结果表明,随吸附时间延长、液固比增大,PAM在盐碱土中的吸附量逐渐增大。PAM在盐碱土中的饱和吸附条件为液固比25,平衡吸附时间8h,在此条件下得出的PAM在盐碱土中的吸附等温线符合Langmuir等温吸附模型,饱和吸附量为0.81mg/g.PAM在盐碱土中的迁移规律为:沿地表随盐碱土深度增加,PAM的含量减少。PAM溶液淋滤量越大,迁移深度越深,各层土壤中PAM的含量也相应增加。降雨迫使PAM沿地表向下多迁移1cm,迁移深度在5—6cm。盐碱土对PAM的截留能力较强,意外泄漏的PAM主要集中在地表下3cm以内处,占总淋滤量的86.1%~99.9%。PAM在大庆市盐碱土中的迁移深度不超过10cm。 相似文献
964.
建立了ASE-GPC—GC-QqQ—MS/MS测定土壤中17种有机氯农药和19种多氯联苯以及MAE-SPE—GC-QqQ—MS/MS测定土壤中16种多环芳烃和18种邻苯二甲酸酯的方法。多环芳烃和邻苯二甲酸酯定量限在0.02~2.81μg/kg之间,有机氯农药和多氯联苯定量限在0.01~0.51μg/kg之间。样品加标浓度在5μg/kg时多环芳烃和邻苯二甲酸酯的平均回收率在66.6%~122.1%之间,相对标准偏差均小于20%;有机氯农药和多氯联苯平均回收率在79.6%~93.2%之间,相对标准偏差均小于15%。 相似文献
965.
This study shows the important role of humic acids in the degradation of 14C and 13C labeled isomer of NP by Sphingomonas sp. strain TTNP3 and the detoxification of the resulting metabolites. Due to the association of NP with humic acids, its solubility in the medium was enhanced and the extent of mineralization of nonylphenol increased from 20% to above 35%. This was accompanied by the formation of significant amounts of NP residues bound to the humic acids, which also occurred via abiotic reactions of the major NP metabolite hydroquinone with the humic acids. Gel permeation chromatography showed a non-homogenous distribution of NP residues with humic acids molecules, with preference towards molecules with high-molecular-weight. Solid state 13C nuclear magnetic resonance spectroscopy indicated that the nonextractable residues resulted exclusively from the metabolites. The chemical shifts of the labeled carbon indicated the possible covalent binding of hydroquinone to the humic acids via ester and possibly ether bonds, and the incorporation of degradation products of hydroquinone into the humic acids. This study provided evidences for the mediatory role of humic acids in the fate of NP as a sink for bacterial degradation intermediates of this compound. 相似文献
966.
Contamination levels of selected organochlorine and organophosphate pesticides in the Selangor River, Malaysia between 2002 and 2003 总被引:3,自引:0,他引:3
In Malaysia, rivers are the main source of public water supplies. This study was conducted from 2002 to 2003 to determine the levels of selected organochlorine and organophosphate pesticides in the Selangor River in Malaysia. Surface water samples have been collected seasonally from nine sites along the river. A liquid-liquid extraction followed by gas chromatography-mass spectrometry technique was used to determine the trace levels of these pesticide residues. The organochlorine pesticides detected were lindane, heptachlor, endosulfan, dieldrin, endosulfan sulfate, o,p'-DDT, p,p'-DDT, o,p'-DDE and p,p'-DDE whereas for organophosphate pesticides, they were chlorpyrifos and diazinon. At the river upstream where a dam is located for public water supply, incidents of pesticide levels exceeding the European Economic Community Directive of water quality standards have occurred. Furthermore, the wetland ecosystems located at the downstream of the river which houses the fireflies community is being threatened by occasional pesticide levels above EPA limits for freshwater aquatic organisms. The occurrence of these residual pesticides in the Selangor River can be attributed to the intense agriculture and urban activity. 相似文献
967.
With Carassius auratus, one of the main economic fish species in Eastern China as test material, this paper studied the hydroxyl radical generation and oxidative stress in its liver under the effect of 2,4,6-trichlorophenol (2,4,6-TCP). Different doses of 2,4,6-TCP were injected intraperitoneally into the fishes, and the Electron paramagnetic resonance (EPR) spectra of hepatic free radicals, activities of superoxide dismutase (SOD), catalase (CAT) and glutathione-s-transferase (GST), levels of reduced glutathione (GSH) and oxidized glutathione (GSSG), and malondialdehyde (MDA) contents were determined 24h after injection. The results showed that under the effects of 2,4,6-TCP, the generation of free radical that was considered to be hydroxyl radical increased significantly, the activities of antioxidant enzymes decreased, with CAT most strongly affected and followed by SOD and GST, the GSH level decreased significantly while GSSG level had little difference, resulting in a decreased GSH/GSSG ratio, and the MDA content increased significantly. All the test parameters showed that C. auratus was subjected to oxidative stress and damage when exposed to 2,4,6-TCP. 相似文献
968.
Historical trends of PCDD/Fs and dioxin-like PCBs in sediments buried in a reservoir in Northern Taiwan 总被引:3,自引:0,他引:3
Polychlorinated dibenzo-p-dioxin (PCDD), polychlorinated dibenzofuran (PCDF) and polychlorinated biphenyl (PCB) concentrations were analyzed at 1-2cm intervals in a sediment core collected from a reservoir in Northern Taiwan to evaluate the organic pollution history. The highest PCDD/F (14.4ng TEQ/kg d.w.) and PCB (0.261ng TEQ(WHO)/kg d.w.) concentrations were determined at 13-15cm (estimated year: 1992). The ages of the levels of sediment core were estimated from the sedimentation rate. Analysis results demonstrate that the PCDD/F concentration of the sediment core measured in the reservoir reached their peak when the municipal waste incinerators (MWIs) in the area started to operate. Furthermore, the decrease in sediment core PCDD/F concentration is related to the time of enforcement of the PCDD/F emission limit set by the Environmental Protection Administration (EPA) in Taiwan. Significant distribution of OCDD in homologue profiles was noted in archived soil samples in Taiwan in which the major input of PCDD/Fs was thought to be atmospheric. Major PCB congeners found in the sediment core were the major components of the commercial PCB products. Input fluxes of PCDD/Fs (5.75-158ng-I-TEQ/m(2)-yr) and PCBs (0.248-3.71ng TEQ(WHO)/m(2)yr) into the reservoir of interest are also calculated from the concentration and sedimentation rate of the sediment. The results reveal that considerable amounts of PCDD/Fs and PCBs were carried into the reservoir of interest in the flood stage but not during normal stage. 相似文献
969.
Synthesis, characterization and application of a novel chemical sand-fixing agent-poly(aspartic acid) and its composites 总被引:1,自引:0,他引:1
A novel sand-fixing agent-poly(aspartic acid) and its composites were synthesized to improve sand particles compressive strength and anti-wind erosion properties. The relationship between the concentration of sand-fixing agent and the sand-fixing properties was studied by three kinds of aging tests. Some composites were choose to improve the sand-fixing property and the composition of 40% xanthan gum and 60% ethyl cellulose were chosen to compare sand-fixing property with lignosulfonate. The results showed that the sand-fixing and water-retaining properties of xanthan gum and ethyl cellulose composites were better than that of lignosulfonate. The biodegradability experiment showed that the PASP and its composites were environment-friendly products and the field test showed that the PASP composites could improve wind erosion disturbance. 相似文献
970.
淮安市环境监测中心站于1999年-2000年对淮安市农产品中重金属以及有机氯、有机磷农药残留量进行了调查。结果表明,粮食和蔬菜作物中,六六六的4种同分异构体只有γ-六六六能检出,检出率分别为24.0%和51.7%,都未超标;DDT的4种同分异要体均未检出;有机磷农药的检出率分别为5%和25%,其中蔬菜中敌敌畏含量出现个别超标现象,倍硫磷、乐果和杀螟松在粮食和蔬菜作物中的含量都不超标。重金属中金属“五毒”在粮食和蔬菜作物中,只有Cr和Pb能检出,Cd、Hg和As都未检出,Cu、Zn和Mn能检出,但不超标。提出,应严格按照农牧渔业部和卫生部颁发的《农药安全使用规定》用药,多使用高效低残留量的“绿色农药”;农业、环保和卫生部门必须加强合作,对蔬菜生产销售的全过程进行监督监测,以确保生产无公害蔬菜。 相似文献