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991.
将《石油炼制工业污染物排放标准》(GB 31570—2015)与石油炼制行业在此之前执行的《大气污染物综合排放标准》(GB16297—1996)等标准进行了比较。指出,《GB 31570—2015》针对不同排放源细化了控制要求,部分指标收严了排放限值,增加了特别排放限值要求,明确扩大了石油炼制工业废水的范围,提出了VOCs的控制要求。分析了其标准在执行中可能出现的问题,提出了实施的建议。 相似文献
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Shi X Liu X Liu G Sun Z Xu H 《Environmental science and pollution research international》2012,19(3):739-747
Introduction
In order to evaluate water quality of a canal system, the spatial pattern of protozoan communities in response to physicochemical variables was studied in the Hangzhou section of the Grand Canal, northern China during a 1-year cycle (February 2008–January 2009). 相似文献993.
以草酸青霉(Penicillium oxalicum)D1为出发菌株,经过紫外线、亚硝酸以及紫外与亚硝酸复合诱变处理,选育出1株高产纤维素酶突变株NU-H,与出发菌株相比,CMCase酶活提高69.8%,滤纸酶活提高75.28%,另外木聚糖酶活,还原糖得率也有显著地提高。通过单因子及正交实验,研究了突变株纤维素酶对稻草粉水解的最适宜条件。结果表明,该菌株酶解糖化的最佳条件为:温度50℃,时间28 h,纤维素酶浓度为60%,底物浓度3%,pH 4.8,还原糖得率为23.25%。 相似文献
994.
Gao Ling Shi Lai Qing Lou Shuai Zhang Xue Wei Xia Qing Sheng Cai 《Environmental science and pollution research international》2013,20(12):8435-8445
Field studies were conducted to investigate arsenic (As), copper (Cu), and zinc (Zn) contamination in agricultural soils and wheat crops at two areas in Huaibei, China. Area A is in the proximity of Shuoli coal mine. In area B, three coal mines and a coal cleaning plant were distributed. The potential health risk of As, Cu, and Zn exposure to the local inhabitants through consumption of wheat grains was also estimated. The results showed that significantly higher (p?<?0.05) concentrations of As, Cu, and Zn were found in soils collected from area B than in those from area A. Arsenic concentrations in wheat sampled from area A were negatively correlated with the distance from the coal mine (p?<?0.001). Concentrations of Cu and Zn in wheat seedlings and grains collected from area B were significantly higher (p?<?0.05) than in those collected from area A, with the exception of Zn in wheat seedlings. Concentrations of Cu and Zn in most wheat grain samples were above the permissible limits of Cu and Zn in edible plants set by the Food and Agriculture Organization/World Health Organization. The hazard index of aggregate risk through consumption of wheat grains was 2.3–2.4 for rural inhabitants and 1.4–1.5 for urban inhabitants. The average intake of inorganic As for rural inhabitants in Huaibei was above 10 μg day?1. These findings indicated that the inhabitants around the coal mine are experiencing a significant potential health risk due to the consumption of locally grown wheat. 相似文献
995.
Zhiqiang Cai Sai Shi Shanshan Li Baike Yang Qiaoli Chen Xiyue Zhao 《Environmental science and pollution research international》2013,20(12):8831-8838
ZJ0273 (propyl 4-(2-(4,6-demethoxy pyrimidin-2-yloxy)benzylamino)benzoate) is a novel herbicide developed in China for oilseed crop. Sixteen bacteria capable of utilizing ZJ0273 as the sole carbon source were isolated from soils. One of the isolates was designated as Bacillus sp. CY based on its physiological and biochemical characteristics and phylogenetic analysis of 16S rDNA sequences. The present study aimed to investigate the ZJ0273 degradation characteristics and kinetics by Bacillus sp. CY which has the ability to utilize ZJ0273 as the sole source of carbon and energy under aerobic conditions. The optimum biodegradation temperature, pH, and ZJ0273 initial concentration were 20–40 °C, 5.0–9.0, and 50–400 mg/l, respectively. Strain CY degraded 65 % of ZJ0273 (initial concentration of 50 mg/l) during 30 days of incubation in basal mineral medium at pH 8.0 and 35 °C. DT50 (half-life value), k (degradation rate constant of ZJ0273), and R 2 are 19.20 days, 0.0361 day?1, and 0.9464, respectively. 相似文献
996.
Li X. Ni Kumud Acharya Xiang Y. Hao Shi Y. Li 《Journal of environmental science and health. Part. B》2013,48(2):153-161
Three common polyphenol compounds Gallic Acid (GA), Pyrogallic Acid (PA) and Catechol (CA) are known to have allelochemical-exhibiting inhibitory effects on the growth of the cyanobacterium Microcystis aeruginosa (M. aeruginosa). Metabolism and antioxidant responses in M. aeruginosa were investigated to elucidate the mechanism by which the three polyphenols inhibit algal growth. The inhibition effects of polyphenols were in the order of CA > PA > GA. The GA and CA exposures increased protein contents, superoxide dismutase (SOD) activity, catalase (CAT) activity and soluble sugar, especially for exposure to GA of 25 mg L?1. Soluble sugar content increased significantly especially when exposed to CA for 72 h. When exposed to PA, protein content, and SOD and CAT activities initially increased but over longer treatment time the activities decreased, in contrast to sugar content. Our results suggest that PA exposure for longer periods of time may inhibit catabolism action, while CA exposure could induce more oxide stress than GA or PA. The overall study showed that polyphenol-induced oxidative damage might be responsible for polyphenol inhibition on M. aeruginosa growth. The increases in cellular antioxidant enzymes and soluble sugar may have been to counteract the oxidative stress. 相似文献
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999.
KMnO4缓释剂的释放性能及其在垃圾渗滤液处理中的应用 总被引:2,自引:0,他引:2
为延长KMnO4在地下水原位修复中的作用时间,通过改变KMnO4与石蜡的分散方式以及KMnO4与石蜡的质量比(P/W),对KMnO4缓释剂的制备过程进行了优化.采用超声与搅拌联用(搅拌速度150 r/min)的分散方式更有利于KMnO4的均匀分布,随着P/W的升高,KMnO4负载量逐渐增大而绝对回收率逐渐减小.静态实验分别研究了缓释剂在8℃、不同pH与DO浓度下的释放性能.结果表明,在8℃环境下,缓释剂仍具有释放性能;缓释剂受pH影响较大而受DO浓度影响较小.利用缓释剂降解垃圾渗滤液中的COD以及对沉淀物进行定量分析.结果表明,缓释剂对COD去除率可高达57.1%,而沉淀量最少仅为投加纯KMnO4的8.5%. 相似文献
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