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41.
应用电感耦合等离子体发射光谱法(ICP—AES法)和紫外一可见分光光度法检测水中的铝元素和钒元素的含量,并对比这两种检测方法的效果。  相似文献   
42.
Recycling of post-consumer waste materials is gaining increased interest due to public awareness, legislative promotion and imposition, economic benefits and appropriate technologies being available. The present paper does not deal with municipal solid waste as such, but only with the recyclable constituents. The paper does not aim at presenting recycling process details and/or fundamental research results, but reviews the major recyclables with their reuse potential, recycling technologies used, problems, solutions and potential areas of future research and development. These target recyclables include paper and cardboard, aluminium cans, glass beverage bottles, scrap metal and steel cans, scrap tyres, batteries and household hazardous waste. The present paper sets the overall picture and deals with paper, cardboard and aluminium cans only. A second part of the paper assesses the other target recyclables. The assessment of the waste availability, the existing and currently developed recovery and recycling technologies, and the economically rewarding markets while recycling, stress the technical, economic and environmental importance of this waste management sector. The activities associated with the recovery and recycling of post-consumer wastes require a strong sustainable engineering input at all phases of the treatment, from input quality control, to the selection of the most appropriate technology and the delivery of the recyclables as readily reusable feedstock.  相似文献   
43.
Some fish‐kills in Basque rivers were studied by gill tissue analysis: Samples were wet digested and the solution was analyzed by atomic absorption spectroscopy. In three cases, the cause was linked to the effluents of an aluminium anodizing factory, cyanide caused one kill and copper wastes were related with another. Three cases were attributed to natural reasons and one of the kills was of unknown origin.  相似文献   
44.
Industrial discharges of Al are increasingly common. In this study, the activities of three antioxidases, malondialdehyde (MDA) content and changes in coelomocytes were investigated in earthworms (Eisenia andrei) exposed to different concentrations of aluminium chloride (range 0–200 mg Al kg?1 dry soil) in artificial soils for 32 days. Within the first 16 days of Al exposure, catalase activity was elevated in most treatments, while the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) were inhibited in all treatments. After 16 days exposure, SOD and GSH-Px activities returned to normal at lower Al concentrations, but were still inhibited at higher concentrations, hence the inhibition of SOD and GSH-Px showed some exposure-level dependence during the late exposure phase. MDA content was significantly elevated from 16 days after initial exposure. Neutral Red retention time of coelomocytes decreased at the highest exposure concentrations after 32 days, and an increased proportion of cells showing membrane damage was also observed at this time using flow cytometry. We conclude that excessive Al in soils can cause oxidative stress and cell damage in earthworms. Hence, Al accumulation in the environment may present an ecological hazard through suppression of the important functions of earthworms in soil ecosystems.  相似文献   
45.
采用加压酸浸法提取粉煤灰中的A12O3和Fe2O3.实验研究了粉煤灰粒径、硫酸质量分数、反应时间、反应温度对粉煤灰中Al2O3和Fe2O3浸取率的影响,并通过SEM对粉煤灰酸浸前后的形貌进行了分析.实验结果表明,当粉煤灰粒径为75μm、硫酸质量分数为50%、反应温度为180℃、反应时间为4h时,粉煤灰中的Al2O3浸取率可达82.4%,Fe2O3浸取率为76.1%,经酸浸后粉煤灰的剩余率为72.4%.  相似文献   
46.
以TEOS为硅源的聚硅氯化铝中铝及硅形态分布   总被引:7,自引:0,他引:7  
以正硅酸乙酯 (TEOS)为硅源 ,合成了新型的聚硅氯化铝 (PASC) ,利用Al Ferron逐时络合比色法和Si Mo逐时络合比色法分别研究了其Al形态及Si形态分布 ,并与常规方法 (以硅酸钠为硅源 )合成的聚硅氯化铝做了比较 .实验结果表明 ,新方法合成的PASC具有铝硅分布均匀 ,分子量较大 ,产品重现性好的优点 .两种方法合成的PASC具有相同的Al形态分布规律 ,即高分子量Al形态含量随B值 (碱化度 )和Si Al摩尔比的增大而增加 ,Al形态随Si Al摩尔比的变化程度随B值的增大而增大 .另外通过新方法发现 ,Si形态分布也具有规律性并和Al形态具有相似的分布特征 ,但Si形态随Si Al摩尔比的变化程度随B值的增大而减小 .  相似文献   
47.
The present project aims to investigate the possible contamination of teas with the trace metals: Al, Cu and Zn. Tea bushes sampled from two tea plantations in the northern part of Guangdong Province accumulated higher concentrations of Cu and Zn in young leaves, and of Al in old leaves. The analysis of the three metals in tea produced in different provinces indicated higher Al levels in those obtained from Guangdong and Yunnan Provinces, which may be due to the lower soil pH in these areas. Green tea had the lowest Al concentration among the four types of tea studied, as only the bud and two young leaves are used, whereas older leaves are used for other types of tea (black, Oolong and Puerh tea). The transfer of Al, Cu and Zn from soil to different parts of tea bushes was low in general, except for Zn at Lechang tea plantation which next to a Pb/Zn mine, where a higher transfer was observed from young leaves to tea products, indicating possible metal contamination during tea processing. However, low concentrations of Cu and Zn (less than 0.07 mg Cu L-1 and 0.17 mg Zn L-1), and moderate amounts of Al (2.1-2.5 mg L-1) were obtained in the tea liquor (1% hot water extracts).  相似文献   
48.
狄平宽  单忠健 《环境科学》1991,12(6):20-24,19
在实验条件下,Ca2+、Al3+离子对高岭土的絮凝过程有不利影响,且pH越高Ca2+的影响越大,pH越低,Al3+的影响越大.运用分子轨道(MO)理论、溶液化学计算、电子探针测试等手段,研究探讨了其作用机理.认为在酸性和中性范围内,Ca2+、Al3+离子及它们的羟基络合正离子与聚丙烯酰胺之间的相互作用造成后者分子链发生卷曲,导致絮凝效果下降;而在pH>9范围内,Ca2+、Al3+的氢氧化物沉积在高岭土表面,阻碍或抑制了聚丙烯酰胺与高岭土之间的氢键作用.  相似文献   
49.
用DWZ接触氧化处理工艺处理屠宰废水   总被引:7,自引:0,他引:7  
实行畜禽定点屠宰后,含有大量有机污染物的畜禽屠宰废水的处理问题急需解决,经浙江省海宁市某畜禽屠宰厂运行证实,采用DWZ接触氧化处理工艺,具有投资少,占地面积小,处理效果好,抗冲击能力强,操作简便,运行费用低等特点,废水经处理后可达到GB8978-1996 Ⅰ级排放标准,得到了社会各界的广泛好评,本文主要介绍了该处理设施的处理工艺,运行特点及优越性,提供一条治理畜禽宰废水的有效途径。  相似文献   
50.
黔北地区土壤中活性铝的分布调查   总被引:2,自引:0,他引:2  
本研究对黔北地区土壤中活性铝的分布进行了分析,结果表明该地区目前土壤活性铝含量的平均水平较低,对于农田及森林系统尚不致有严重影响,但酸性降水对该地区黄壤中铝的溶出有潜在性危害作用。  相似文献   
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