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31.
对采用原子吸收火焰法次灵敏线测定污水和电镀污泥中高含量的锌进行了研究。试验结果表明:在锌浓度50.0~600.0mg/L之间,溶液锌含量与吸光度呈线性关系。线性回归方程为y=0.000661x-0.0007,相关系数γ=0.9998。方法检出限为25.0mg/L,相对标准误差(RSD)<2.96%,加标回收率为92.5%~105%,与标准法的相对误差<2.76%。  相似文献   
32.
在2010年全年涡湖富营养化现状调查基础上,评价了涡湖营养程度,并分析了20年来(1986年-2006年)总氮TN、总磷TP、氮磷比TN/TP和CODMn的发展趋势。结果表明,按照综合营养状态指数法,目前涡湖呈轻度富营养化,且有进一步恶化的趋势。20年来TN,TP和CODMn有较大增长,氮磷比下降。由此,提出了漏湖富营养化综合防治的建议措施,包括污染源控制、围网养殖调整、清淤工程和沉水植被恢复工程。  相似文献   
33.
描述了安徽省地震局"十一五"期间安装的5套钻孔体应变仪的地质构造特点与钻孔岩芯物理特性,介绍了TJ-Ⅱ体应变仪的运行情况。通过对两次强震活动的同震效应分析,初步探讨了地理、地质构造条件不同的情况下,各观测井对记录应力活动能力强弱的反映。  相似文献   
34.
Kinetics of enzymatic unhairing by protease in leather industry   总被引:2,自引:0,他引:2  
In leather industry, unhairing is a heavy pollution operation. The conventional lime-sulfide process produces a large amount of sulfide which is toxic to health and difficult to dispose. Moreover, conventional lime-sulfide process leads to the destruction of the hair causing increased COD, BOD and TDS loads in the effluent. As an alternative method, enzymatic unhairing is a promising clean technology. The main utilized enzyme preparations are proteases.There are many reports about enzymatic unhairing, most of which are qualitative. The kinetics of enzymatic unhairing by protease was discussed in this article. It will provide useful information to enzymatic unhairing. In our research, by analysis of the concentrations of released total protein in enzyme bath during protease unhairing, the good linearity between released total protein and square root of time (min1/2) was obtained at the initial stage. The good linearity suggests that enzymatic unhairing by protease is a diffusion-controlled process at the initial stage. The analysis of kinetics of released saccharides also confirms the same conclusion. On the other hand, the same characteristics between the kinetics of released saccharides and that of released total protein further confirms that it is the hydrolysis of core protein by protease that leads to the degradation of proteoglycans and the release of protein and saccharides. However, in our tests, the kinetics of released collagen indicates that the injury to skin took place in 3-6 h. Therefore, it’s necessary to control the time of protease unhairing within an appropriate limit.  相似文献   
35.
中国红十字会是中国整体灾害应急体系的重要组成部分,建立健全红十字会应急体系建设对备灾、应急工作至关重要。中国红十字会应急体系建设主要包括红十字会应急预案、应急物资储备系统、应急救援队伍、应急宣传培训与演练、信息传递系统等。红十字会应急体系建设也存在应急预案的不健全和缺乏针对性、物资储备系统有待健全、应急队伍建设有待加强、应急救护体系不协调等不足。本文从改革和健全红十字会应急预案、大力发展红十字应急组织、深入推进红十字会物资储备库建设、普及全民应急救护、健全红十字应急网络、学习西方国家经验等方面提出加强红十字会灾害应急工作的对策建议。  相似文献   
36.
Journal of Material Cycles and Waste Management - This study aimed at investigating the impacts of different percentages of biochar (BC) (at 0, 15, and 25%; by vol.) and/or cattle manure (CM) (at...  相似文献   
37.
• Pd nanoparticles could be reduced and supported by activated sludge microbes. • The effect of biomass on Pd adsorption by microbes is greater than Pd reduction. • More biomass reduces Pd particle size, which is more dispersed on the cell surface. • When the biomass/Pd add to 6, the catalytic reduction rate of Cr(VI) reaches stable. Palladium, a kind of platinum group metal, owns catalytic capacity for a variety of hydrogenations. In this study, Pd nanoparticles (PdNPs) were generated through enzymatic recovery by microbes of activated sludge at various biomass/Pd, and further used for the Cr(VI) reduction. The results show that biomass had a strong adsorption capacity for Pd(II), which was 17.25 mg Pd/g sludge. The XRD and TEM-EDX results confirmed the existence of PdNPs associated with microbes (bio-Pd). The increase of biomass had little effect on the reduction rate of Pd(II), but it could cause decreasing particle size and shifting location of Pd(0) with the better dispersion degree on the cell surface. In the Cr(VI) reduction experiments, Cr(VI) was first adsorbed on bio-Pd with hydrogen and then reduced using active hydrogen as electron donor. Biomass improved the catalytic activity of PdNPs. When the biomass/Pd (w/w) ratio increased to six or higher, Cr(VI) reduction achieved maximum rate that 50 mg/L of Cr(VI) could be rapidly reduced in one minute.  相似文献   
38.
Environmental Science and Pollution Research - In this study, porous activated carbon balls supported by nanoscale zero-valent iron composites (Fe@PACB-700) were used for the first time for the...  相似文献   
39.
Dietary uptake is the major way that inorganic arsenic (iAs) enters into benthic fish; however, the metabolic process of dietborne iAs in fish muscle following chronic exposure remains unclear. This was a 40-day study on chronic dietborne iAs [arsenite (AsIII) and arsenate (AsV)] exposure in the benthic freshwater food fish, the crucian carp (Carassius auratus), which determined the temporal profiles of iAs metabolism and toxicokinetics during exposure. We found that an adaptive response occurred in the fish body after iAs dietary exposure, which was associated with decreased As accumulation and increased As transformation into a non-toxic As form (arsenobetaine). The bioavailability of dietary AsIII was lower than that of AsV, probably because AsIII has a lower ability to pass through fish tissues. Dietary AsV exhibited a high potential for transformation into AsIII species, which then accumulated in fish muscle. The largely produced AsIII considered more toxic at the earlier stage of AsV exposure should attract sufficient attention to human exposure assessment. Therefore, the pristine As species and exposure duration had significant effects on As bioaccumulation and biotransformation in fish. The behavior determined for dietborne arsenic in food fish is crucial for not only arsenic ecotoxicology but also food safety.  相似文献   
40.
Efficient removal of chlorine from PVC achieved by two-stage heat-treatment (280 and 410 degrees C) provided chlorine-free isotropic pitch containing additive. The pitch was stabilized and carbonized into porous carbons with surface areas of approximately 300 m2/g. Resultant porous carbons showed three pore structures of supermicropore, micropore and mesopore. The generation of CO2 from the decomposition of the CaCO3 additive in waste PVC is responsible for the development of porous structures. The surface area of the carbonized product increased after the removal of CaO.  相似文献   
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