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631.
Pei-wen Zheng Jian-bing Wang Zhen-yu Zhang Peng Shen Peng-fei Chai Die Li Ming-juan Jin Meng-Ling Tang Huai-chu Lu Hong-bo Lin Kun Chen 《Environmental science and pollution research international》2017,24(23):18860-18869
Acute upper and lower respiratory infections are main causes of mortality and morbidity in children. Air pollution has been recognized as an important contributor to development and exacerbation of respiratory infections. However, few studies are available in China. In this study, we investigated the short-term effect of air pollution on hospital visits for acute upper and lower respiratory infections among children under 15 years in Ningbo, China. Poisson generalized models were used to estimate the associations between air pollution and hospital visits for acute upper and lower respiratory infections adjusted for temporal, seasonal, and meteorological effects. We found that four pollutants (PM2.5, PM10, NO2, and SO2) were significantly associated with hospital visits for acute upper and lower respiratory infections. The effect estimates for acute upper respiratory infections tended to be higher (PM2.5 ER = 3.46, 95% CI 2.18, 4.76; PM10 ER = 2.81, 95% CI 1.93, 3.69; NO2 ER = 11.27, 95% CI 8.70, 13.89; SO2 ER = 15.17, 95% CI 11.29, 19.19). Significant associations for gaseous pollutants (NO2 and SO2) were observed after adjustment for particular matter. Stronger associations were observed among older children and in the cold period. Our study suggested that short-term exposure to outdoor air pollution was associated with hospital visits for acute upper and lower respiratory infections in Ningbo. 相似文献
632.
CongCong Liu Cheng Huang XiuYun Sun Rui Li Jiansheng Li Jinyou Shen Weiqing Han Lianjun Wang 《Environmental science and pollution research international》2017,24(21):17474-17484
The important criteria in anaerobic digestion is the rate-limiting step which decides the fate of value-added products especially from waste-activated sludge (WAS). Hence, the present study investigated the effect of magnesium (Mg2+) addition on anaerobic digestion of WAS. The lab-scale experiments were conducted at 25 °C with Mg2+ doses ranging from 0.01 to 0.2 mol/L. Maximum total volatile fatty acids (VFAs) production (372.78 mg COD/L) occurred at a Mg2+ dose of 0.2 mol/L, which was about eight times higher than the control tests. Further, Mg2+ addition facilitated sludge dewaterability and phosphorus removal. The mechanism of improved VFAs generation was analyzed from the view of both chemical and biological effects. Chemical effect significantly enhanced the release of calcium and iron in WAS, resulting in the disintegration of WAS, which benefited hydrolysis and acidification processes. Illumina MiSeq sequencing analysis revealed that enrichment of functional bacteria and the increase of bacterial diversity were obtained in the 0.2 mol Mg2+/L experiment, while the influence was negative on the reactor with 0.025 mol/L Mg2+. Meanwhile, methanogens were accordantly inhibited in the experiments with Mg2+ addition. 相似文献
633.
Yang Chong Zhu Nengwu Shen Weihang Zhang Ting Wu Pingxiao 《Journal of Material Cycles and Waste Management》2017,19(1):247-255
Journal of Material Cycles and Waste Management - The goal of this study is to determine the potential of Acidithiobacillus ferrooxidans strain Z1 in bioleaching of metal concentrates of waste... 相似文献
634.
用亨盖特(Hungate)厌氧技术,以甲醇为唯一碳源获得了甲烷八叠球菌的富集培养物,以甲醇或乙酸钠(或两者各50%)为碳源滚管培养,获得了以甲烷八叠球菌的分离培养物。用聚乙烯醇(PVA)为包埋剂对甲烷八叠球菌sp固定化,并对其特性进行了研究。结果表明:固定化甲烷八叠球菌与非固定化甲烷八叠球菌的总产气量相似,但两者的产气特性有明显不同。固定化甲烷八叠球菌产气迟于非固定化甲烷八叠球菌,固定化甲烷八叠球菌的产气集中,在产气的6天中,平均日产气量30.88mL甲烷,最高产气量可达2.80mL甲烷/h,在产气高峰两天中的产气量占总产气量的66.0%。非固定化甲烷八叠球菌产气平稳,平均日产气量为8.91mL甲烷。固定化甲烷八叠球菌的电子显微镜观察结果表明,细胞在固定介质中多呈较大包囊存在,包囊直径30~50μm。 相似文献
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北京市规定新建的宾馆、饭店要建设中水道,将部分排水就地处理回用,以缓解供水紧张和减轻排水设施的负担。本文就设立中水道的意义;中水道不同水质的处理工艺的确定;中水道的技术经济分析及要有计划地实施中水道工程诸问题,结合研究和建设实践提了一些看法。 相似文献
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一株高效解磷细菌的紫外诱变选育及其在红壤稻田施用效果 总被引:1,自引:0,他引:1
红壤对磷有强大吸附固定力,磷肥易被土壤中活性铁、铝固定而使有效态磷转化为各种形态的非有效磷,从而大大降低磷肥的利用率。解磷菌能使土壤中难溶性或不溶性的磷转化为易于被植物吸收利用的磷。通过对江西鹰潭红壤分离筛选并经过紫外诱变获得一株性状稳定的高效解磷细菌Y8。经鉴定,菌株Y8为蜡状芽孢杆菌(Bacillus cereus)。通过与生产中应用的徐州华龙高效复合菌肥厂的解磷细菌X3相比,菌株Y8降解有机磷、溶解Ca3(PO4)2的能力均比较高,分别为155.3mg·L^-1和240.1mg·L^-1。研究各种理化因子对菌株Y8解磷能力的影响,确定了菌株Y8的最佳培养条件为葡萄糖20g·L^-1、NH4(SO4)21.5g·L^-1、pH7.0、温度为35℃,在该条件下菌株Y8溶解Ca3(PO4)2的量为295.6mg·L^-1。在江西鹰潭红壤稻田的施用试验表明,将菌株Y8制成微生物菌剂施用于水稻田可起到减施化肥的作用。 相似文献