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51.
分析了安全生产标准化与其他管理体系的关系,并结合当前推进安全生产标准化工作的具体要求,阐述了安全生产标准化的作用。  相似文献   
52.
UASB-FEO-氨吹脱-CASS工艺在垃圾渗滤液处理中的应用   总被引:2,自引:0,他引:2  
针对垃圾渗滤液可生化性差、氨氮含量高等特点和国内处理工艺现状,采用UASB-FEO-氨吹脱-CASS工艺处理合肥市龙泉山城市垃圾填埋场垃圾渗滤液。介绍了工艺的重要构筑物及其设计参数。运行实践表明,整套装置运行平稳,出水水质满足设计要求。根据出水水质对该工艺进行技术分析以及运行结果的讨论,并与新发布的技术规范及排放标准进行对比分析。  相似文献   
53.
通过室内模拟实验,探讨了在非水相硝基苯污染含水层的条件下,其在含水层中的迁移及释放规律。迁移规律表明,非水相硝基苯并非在含水层中直接进行垂向迁移,而是一方面在自身重力作用下向含水层下部迁移,另一方面在地下水流的作用下随地下水同向运移,整体表现为随地下水流的侧向运移,并最终迁移至含水层底部。释放规律表明,非水相硝基苯在含水层迁移的过程中会向地下水大量释放,释放出的硝基苯在水流的作用下随地下水同向运移,污染源及迁移至含水层底部的非水相硝基苯均存在再次释放。  相似文献   
54.
Environmental Geochemistry and Health - Based on 1625 data collected from the published literature, the geochemistry of tin (Sn) in Chinese coals, including the abundance, distribution, modes of...  相似文献   
55.
A field survey was conducted to investigate the present situation and health risk of arsenic (As), lead (Pb), cadmium (Cd), copper (Cu), and zinc (Zn) in soils and vegetables in a multi-metal mining area, Gejiu, China. Furthermore, three vegetables (water spinach, potato, and summer squash) containing high metal concentrations were selected to further analyze metal speciation. The results showed that the average concentrations of five metals in soil exceeded the limiting values, and their bioavailable concentrations were significantly positively correlated to the total ones. Heavy metals in the edible parts of vegetables also exceeded the corresponding standards. The leaves of pakchoi, peppermint, and coriander had a strong metal-accumulative ability and they were not suitable for planting. Except the residue forms, the main forms of metals in the edible parts of three selected vegetables were ethanol-, NaCl-, and HAc-extractable fractions for As, Pb, and Cd, respectively; however, Cu was mainly presented as NaCl-extractable and Zn as HAc-extractable fractions. A high proportion of ethanol-extractable As showed that As bioactivity and toxic effects were the highest. Although the total and bioavailable Cd were high in soil, its speciation in vegetables was mainly presented as HAc-extractable fraction, which has a relatively low bioactivity. Lead and arsenic were imposing a serious threat on the local residents via vegetable consumption.  相似文献   
56.
Quinestrol has shown potential for use in the fertility control of the plateau pika population of the Qinghai–Tibet Plateau. However, the environmental safety and fate of this compound are still obscure. Our study investigated degradation of quinestrol in a local soil and aquatic system for the first time. The results indicate that the degradation of quinestrol follows first-order kinetics in both soil and water, with a dissipation half-life of approximately 16.0 days in local soil. Microbial activity heavily influenced the degradation of quinestrol, with 41.2 % removal in non-sterile soil comparing to 4.8 % removal in sterile soil after incubation of 10 days. The half-lives in neutral water (pH 7.4) were 0.75 h when exposed to UV light (λ?=?365 nm) whereas they became 2.63 h when exposed to visible light (λ?>?400 nm). Acidic conditions facilitated quinestrol degradation in water with shorter half-lives of 1.04 and 1.47 h in pH 4.0 and pH 5.0 solutions, respectively. Moreover, both the soil and water treatment systems efficiently eliminated the estrogenic activity of quinestrol. Results presented herein clarify the complete degradation of quinestrol in a relatively short time. The ecological and environmental safety of this compound needs further investigation.  相似文献   
57.
巢湖蓝藻的机械清除工艺以及藻水分离实验研究   总被引:1,自引:0,他引:1  
对巢湖蓝藻进行机械清除以及藻水分离实验研究,实验采用的浮式围栏引导-机械清除-投加剥离液辅助机械清除工艺处理量大,除藻效率高,筛网过滤-浓缩-卧螺离心机脱水成藻泥的藻水分离工艺较为理想,藻泥含水率仅为89%。2011年5—10月在巢湖运用上述方法清除湖面水华蓝藻,共处理富藻水1.6万m3,得到藻泥970 t,累计清除蓝藻106.7 t(干重)。按照所清除蓝藻的总氮、总磷的平均含量计算,相当于从湖中移除了氮6.25 t,磷2.1 t。表明在富营养湖泊中水华蓝藻大量暴发时,采用上述方法除藻,对控制蓝藻水华污染,有效降低内源氮、磷等污染物负荷具有十分重要的作用。  相似文献   
58.
3种典型微生物农药对家蚕的毒性研究   总被引:1,自引:0,他引:1  
苏云金芽孢杆菌、球孢白僵菌以及棉铃虫核型多角体病毒是细菌类、真菌类和病毒类微生物农药的典型代表。为了明确微生物农药对家蚕的毒性影响,选取以上3种典型微生物农药,分别探究其对家蚕的毒性。结果显示:苏云金杆菌原药对家蚕LC50值为1.33×105CFU·m L-1;球孢白僵菌原药对家蚕LC50值为1.14×106CFU·m L-1;棉铃虫核型多角体病毒母药对家蚕LC50值大于1.00×108PIB·m L-1。与此同时,通过进一步试验,明确了以上3种微生物农药对家蚕结茧率、死笼率、全茧量、茧层量等关键指标的影响。结果显示:除了棉铃虫核型多角体病毒母药,高浓度苏云金杆菌原药、球孢白僵菌原药对家蚕的结茧率和死笼率均具有显著影响;3种微生物农药对家蚕产茧能力指标全茧量、茧层量以及蛹重均无显著性影响。  相似文献   
59.
In the present study, biosynthesis of gold nanoparticles (AuNPs) by the cells (cells-AuNPs) and cell-free extracts (extracts-AuNPs) of a new fungus Mariannaea sp. HJ was reported. The as-synthesized particles were characterized by UV-vis spectroscopy, transmission electron microscopy (TEM), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR). The effects of different parameters on AuNP biosynthesis were investigated, and initial gold ion concentration of 2 mM, pH 7, was demonstrated to be suitable for both cells-AuNP and extracts-AuNP syntheses. The cells-AuNPs were of various shapes, including sphere, hexagon, and irregular shapes, with an average size of 37.4 nm, while the extracts-AuNPs were almost spherical and pseudo-spherical with an average size of 11.7 nm. XRD pattern suggested that the crystal structure of both AuNPs was face-centered cubic. FTIR spectra implied that some biomolecules from the fungal cell walls or cell-free extracts were involved in the formation of AuNPs. The as-synthesized AuNPs were demonstrated to have excellent catalytic activities for the reduction of 4-nitrophenol with the catalytic rate constants of 5.7 × 10?3/s for cells-AuNPs and 24.7 × 10?3/s for extracts-AuNPs. To the best of our knowledge, this is the first report on AuNP biosynthesis by Mariannaea sp.  相似文献   
60.
采用新型膜蒸馏技术对水中As(III)与As(Ⅴ)的去除展开了研究。实验结果表明,膜蒸馏对水中As (III)及As (Ⅴ)具有较高的去除能力:当产水中砷含量超过10 μg/L时,原水中As (III)与As (Ⅴ)的浓度可分别高达40 mg/L和2 000 mg/L。局部润湿现象的存在导致As (III)及As (Ⅴ)跨膜至产水侧,PVDF微孔膜在溶液中的负电性以及As (III)与 As (Ⅴ)在溶液中存在形式的不同导致膜蒸馏对两者去除能力的差异。360 h连续运行过程中产水通量及电导率稳定,且整个过程中As (III)均低于检测限,说明PVDF微孔膜具有良好的疏水性和稳定的除砷性能。  相似文献   
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