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901.
Environmental Science and Pollution Research - Se can regulate Cd accumulation and translocation in plants; however, such effects can be controversial because of the differences in plant species...  相似文献   
902.
Journal of Material Cycles and Waste Management - The development of biogas programs in rural China has led to great economic, social, ecological and environmental benefits. The focus of this study...  相似文献   
903.
Environmental Science and Pollution Research - As a kind of renewable resources, the effective utilization of marine resources has a significant influence on the sustainable development of economy....  相似文献   
904.
高活性高耐受甲醛降解菌株的分离鉴定及降解条件研究   总被引:3,自引:1,他引:3  
徐云  金晶  郑重  钟卫鸿  吴石金  邱乐泉  陈建孟 《环境科学》2010,31(10):2481-2486
以甲醛为唯一碳源,从土壤中分离得到1株甲醛降解菌,经形态学观察、生理生化特性研究和16SrDNA鉴定,该菌株属于恶臭假单胞菌(Pseudomonas putida).通过单因素试验和正交试验考察培养基及培养条件对菌株降解甲醛的影响,得出该菌株降解甲醛的最适条件为:蛋白胨1.2g/L,KH2PO4 4g/L,K2HPO4 3g/L,MgSO4·7H2O 0.2g/L,微量元素母液0.1mL/L,温度30℃,pH值8.在最适降解条件下,分别对不同初始浓度甲醛进行降解试验,结果表明该菌株对甲醛的耐受浓度可达6g/L,54h可将其降解86%,46h可将5g/L甲醛全部降解,35h可全部降解4g/L甲醛.  相似文献   
905.
输油站的安全管理与消防   总被引:4,自引:0,他引:4  
从输油站安全管理的方针、目的、管理对象及内容等方面进行分析和阐述,提出了预防输油站事故发生的技术措施和管理措施,可为输油站安全运营提供参考。  相似文献   
906.
The construction of metro in China is in a period of an unprecedented development in recent years, and the passengers are in high density within the metro during the operation time, the problem of occupant safety in emergencies has attracted more and more attentions. During the design and operation stages, modeling of the metro station evacuation capacity by using the computational models is an effective measure for guaranteeing the metro evacuation safety in the future. In this article, the safety strategy of evacuation in metro stations is first investigated and established, which involves the occupants needed to be evacuated, the evacuation route, and the safety zone. Then, an engineering calculation method for the metro station evacuation time is proposed. Based on the experimental data, simulation of evacuation process in different fire cases is conducted by using an agent-based model, so as to study the features of occupant evacuation behavior, the evacuation time, the passage flow rate, and the strategy of using the escalator as evacuation passage. These conclusions will be helpful for guiding the safe evacuation design of metros in China.  相似文献   
907.
在对某制药厂鼓风机房现场噪声测量的基础上,对机房的噪声特性和噪声源进行了分析,提出针对噪声特性的吸声和隔声方案.在该方案不能满足要求的情况下提出在电机和鼓风机的基础下面安装弹簧隔振器、使用金属软管进行管道隔振的补充方案.测试表明,补充方案是有效的控制措施,降噪效果明显,能完全满足厂家提出的要求.  相似文献   
908.
• Cu2O NPs/H2O2 Fenton process was intensified by membrane dispersion. • DMAc removal was enhanced to 98% for initial DMAc of 14000 mg/L. • Analyzed time-resolved degradation pathway of DMAc under ·OH attack. High-concentration industrial wastewater containing N,N-dimethylacetamide (DMAc) from polymeric membrane manufacturer was degraded in Cu2O NPs/H2O2 Fenton process. In the membrane-assisted Fenton process DMAc removal rate was up to 98% with 120 min which was increased by 23% over the batch reactor. It was found that ·OH quench time was extended by 20 min and the maximum ·OH productivity was notably 88.7% higher at 40 min. The degradation reaction rate constant was enhanced by 2.2 times with membrane dispersion (k = 0.0349 min1). DMAc initial concentration (C0) and H2O2 flux (Jp) had major influence on mass transfer and kinetics, meanwhile, membrane pore size (rp) and length (Lm) also affected the reaction rate. The intensified radical yield, fast mass transfer and nanoparticles high activity all contributed to improve pollutant degradation efficiency. Time-resolved DMAc degradation pathway was analyzed as hydroxylation, demethylation and oxidation leading to the final products of CO2, H2O and NO3 (rather than NH3 from biodegradation). Continuous process was operated in the dual-membrane configuration with in situ reaction and separation. After five cycling tests, DMAc removal was all above 95% for the initial [DMAc]0 = 14,000 mg/L in wastewater and stability of the catalyst and the membrane maintained well.  相似文献   
909.
为发掘不同特性脂肪酶微生物资源,采用纯培养方法从青海高寒草地、雅安山区、成都平原分离得到产脂肪酶菌株54株.通过对菌株的DNA进行ERIC-PCR指纹图谱分析,按聚类树划分为5个操作分类单元.16S rDNA序列测定和聚类分析显示,分离菌株分布于芽孢杆菌属(Bacillus)、克雷伯氏菌属(Klebsiella)、假单胞菌属(Pseudomonas)、葡萄球菌属(Staphylococcus)、肠杆菌属(Enterobacter).多样性分析表明,与青海高寒草地、雅安山区相比,成都平原产脂肪酶菌株遗传多样性更为丰富.在54株菌中都出现了300 bp和1 300 bp两个特异且稳定出现的条带,这两个特异条带可能是产脂肪酶菌株的SCAR标记条带.  相似文献   
910.
A study was conducted to investigate the occurrence and behavior of six endocrine-disrupting chemicals (EDCs) in sewage, river water, and seawater from the Pearl River Delta (PRD). The six EDCs under study were 4-nonylphenol (NP), bisphenol A (BPA), 17α-ethynylestradiol (EE2), estrone (E2), 17β-estradiol (E2), and estriol (E3). These EDCs, predominated by BPA, were found in high levels in the influents and the effluents of sewage treatment plants in the area. The relatively high concentrations (0.23–625 ng/L) of the EDCs detected in the receiving river water suggested that the untreated sewage discharge was a major contributor. The EDCs detected in eight outlets of the Pear River and the Pear River Estuary were in the ranges of 1.2–234 and 0.2–178 ng/L, respectively. The estrogen equivalents in the aquatic environments under study ranged from 0.08 to 4.5 ng/L, with E1 and EE2 being the two predominant contributors. As the fluxes of the EDCs from the PRD region to the nearby ocean are over 500 tons each year, the results of this study point to the potential that Pearl River is a significant source of the EDCs to the local environment there.  相似文献   
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