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21.
我国大部分变电站位于农村地区,因无接入城市污水管网条件,农村变电站生活污水需就地处理后达标排放。变电站生活污水存在水量少、时变化系数大等特点,现有处理工艺不能正常运行或无法达标排放。本文借鉴农村生活污水处理技术,提出了生物组合法处理对策,可为变电站生活污水处理提供参考。  相似文献   
22.
王袁 《环境与发展》2020,(1):180-180,182
我国经济飞快的发展速度,不但丰富了人们的生活内容、方便了人们的生活,而且还在人们生活中产生了一些负面影响,大气污染问题已经引起了国家政府以及我国民众的一致关注,国家还为此制定并颁布了相关的整顿治理措施,在大气环境治理方面,大气监测是重要手段,本文对大气环境监测全过程质量控制问题展开分析研究。  相似文献   
23.
超临界水氧化去除含酚废水TOC的动力学研究   总被引:21,自引:1,他引:20  
本文利用自行设计的一套连续式超临界水氧化实验装置,以过氧化氢为氧化剂,处理实验室模拟含酚废水。在超临界条件下(P=30MPa,T=400℃,440℃,480℃,520℃)进行超临界水氧化实验。结果表明,TOC去除速率在氧化剂过量10倍的情况下,对TOC是2.15级反应。速率常数与温度的关系符合阿仑尼乌斯公式。反应的实验活化能为171.7kJ/mol,前置因子A为2.99×1011。  相似文献   
24.
The potential of a chlorophenol (CP)-adapted consortium to dechlorinate polychlorinated biphenyls (PCBs) in sewage sludge was investigated. Results show that dechlorination rates differed significantly depending on sludge source and PCB congener. Higher total solid concentrations in sewage sludge and higher concentrations of chlorine in PCB resulted in slower dechlorination rates. No significant difference was found for 2,3,4,5-CB dechlorination from pH 6.0 to pH 8.0; however, dechlorination did not occur at pH 9.0 during a 41-day incubation period. Results show that at concentrations of 1 to 10 mg/L, the higher the PCB concentration, the faster the dechlorination rate. In addition, dechlorination rates were in the following order: methanogenic conditions > sulfate-reducing conditions > denitrifying conditions. The addition of acetate, lactate, pyruvate, and ferric chloride decreased lag times and enhanced dechlorination; however, the addition of manganese dioxide had an inhibitory effect. Dechlorination rates were also enhanced by the addition of PCB congeners, including 2,3,4-CB, 2,3,4,5-CB and 2,3,4,5,6-CB in mixture. Overall results show that the CP-adapted consortium has the potential to enhance PCB dechlorination. The optimal dechlorination conditions presented in this paper may be used as a reference for feasibility studies of PCB removal from sludge.  相似文献   
25.
废石粉渣制备混凝剂及其除浊净水效果研究   总被引:3,自引:0,他引:3  
利用废石粉渣制备无机混凝剂,并研究所得初产品对硅藻土悬浮液和受污湖水样品进行处理的适宜操作条件以及除浊净水效果,结果表明,利用某些废石粉渣制备的混凝剂有较好效果,但制备工艺有待改善。  相似文献   
26.
This paper proposes a reliability analysis system, which can be widely applied to the cases in which a reservoir is operated to meet several purposes such as flood control, energy generation, irrigation, domestic and industrial water supply, etc. The presented system has a structure of three levels.1. Decision-making.2. Tradeoff analysis.3. The third level that mainly consists of three subsystems:i – The reservoir flood risk analysis subsystem by flood control simulation.ii – The benefit promotion subsystem of reservoir operation using Stochastic Dynamic Programming. In this subsystem, the Lagrange multipliers are introduced into the objective function to take into account the water supply failures. This method guarantees that each run of the SDP will necessarily derive a non-inferior policy for reservoir operation.iii – The reservoir operation simulation subsystem to derive the performance indices associated with the reservoir operation policies. With the input and feedback between the second level and the subsystems of the third level, a great deal of efficient operation policies and the associated performance indices can be obtained. Then the tradeoff relationships between different performance indices can be derived for the decision makers. With application to Yudong Reservoir in Yunnan province of China, the presented analysis system is practically tested.  相似文献   
27.
Scenarios of major terrestrial ecosystems in China   总被引:2,自引:0,他引:2  
The spatial pattern and mean-center shift of major terrestrial ecosystems, termed Holdridge Life Zones (HLZ), during the periods from 1961 to 1990 (T1), from 2010 to 2039 (T2), from 2040 to 2069 (T3) and from 2070 to 2099 (T4) were analyzed by combining the zonal patterns of climatic change in China and the climatic change scenarios of HadCM2 and HadCM3. The results showed that nival area would decrease rapidly with temperature increase in the future. HadCM2 and HadCM3 predicted that the nival areas might disappear in 552 years and 204 years, respectively. Using both HadCM2 and HadCM3, the five HLZ types with the largest areal extent are nival zone, cool temperate moist forest, warm temperate moist forest, subtropical moist forest and boreal wet forest, which collectively account for more than 50% of China's land mass. Among these five HLZ types, nival zone, warm temperate moist forest and boreal wet forest would decrease continuously, whereas subtropical moist forest and cool temperate forest would increase continuously during the four periods. HLZ diversity and patch connectivity would increase continuously in the 21st century. The shift distances of mean centers of HLZ types simulated using HadCM3 were markedly greater than those simulated using HadCM2, in general. The results from both HadCM2 and HadCM3 showed that boreal wet forest, subtropical moist forest, tropical dry forest, warm temperate moist forest and subtropical wet forest had bigger shift ranges, indicating that these HLZ types are more sensitive to the climatic change scenarios of HadCM2 and HadCM3.  相似文献   
28.
一种赤腹松鼠种群数量的估计方法   总被引:4,自引:0,他引:4  
赤腹松鼠剥食树皮的行为对林木危害严重,根据野外长期的观察和研究发现,赤腹松鼠在剥落树皮上遗留下来的上门齿齿印间距具有个体差异,可以用作个体识别的依据.对2003年监测样地内赤腹松鼠在剥落树皮上的齿印间距测量记录,并统计分析以估计赤腹松鼠的个体数量.结果表明:种群数量与危害率的相关系数为0.876,P=0.01,表现出很强的正相关关系;显示在较小面积内,该方法可以用来估计赤腹松鼠的个体数量.同时对该方法的基本条件和局限进行了讨论.图2表4参10  相似文献   
29.
盐碱胁迫对水稻主要生育性状的影响   总被引:23,自引:0,他引:23  
对7个水稻品种(品系)和苏打盐碱土(pH6.5~19.81)进行盆栽试验,探讨了盐碱胁迫对水稻株高、秆长、分蘖和抽穗期等主要生育性状的影响。结果表明,盐碱胁迫使水稻株高降低、秆长缩短,且盐碱度越大,降低幅度越大;盐碱胁迫使水稻单株分蘖力明显下降,使分蘖高峰明显推迟或不出现分蘖高峰;水稻抽穗期随着盐碱度的提高,其延长的天数越长,并且发现不耐盐碱的早熟品种比耐盐碱的中晚熟品种抽穗晚;水稻成熟期的株高或秆长不宜作为衡量其耐盐碱强弱的主要指标,只能作为一般参考指标。水稻单株分蘖力(茎蘖数)和抽穗期存在明显的基因型差异,是衡量水稻耐盐碱强弱的良好指标。盐碱地种稻应重视选择单株分蘖力较强的耐盐碱品种,这对提高单位面积的有效穗数具有十分重要的意义。  相似文献   
30.
运用电生理学方法,观察Hg(2+)、Zn(2+)联合对克氏螯虾第一触角内侧枝神经动作电位放电的影响.当Hg(2+)、Zn(2+)浓度分别达到0.000025mg/L和0.05mg/L时,这两种离子联合对触角神经的毒性作用潜伏期(TL)为46.75±22.69min(N=8),触角神经动作电位放电持续时间(DD)为115.28±40.95min,表示其放电频率(Fn/Fl)与作用时间关系的直线回归方程的b值为-0.0818,与渔业水体最高允许Zn(2+)含量0.1mg/L比较,两者间无显著差异(P>0.1).说明Hg2+对Zn(2+)的毒性具有增强效应.因此,在对有Hg(2+)和Zn(2+)污染的水体进行评估时,似应考虑到Hg(2+)对Zn(2+)毒性的增强效应.  相似文献   
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