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921.
阐述了当前环境监测的现状,指出了新常态下环境监测的机遇和挑战,提出了环境监测要抓住机遇,面对挑战,充分发挥职能,保证环境监测数据真实,完善环境监测体系,深度运用环境监测数据,实行信息公开。  相似文献   
922.
In this study, the hydrochemical characteristics of shallow groundwater were analyzed to get insight into the factors affecting groundwater quality in a typical agricultural dominated area of the North China Plain. Forty-four shallow groundwater samples were collected for chemical analysis. The water type changes from Ca·Na-HCO3 type in grass land to Ca·Na-Cl (+NO3) type and Na (Ca)-Cl (+NO3+SO4) type in construction and facility agricultural land, indicating the influence of human activities. The factor analysis and geostatistical analysis revealed that the two major factors contributing to the groundwater hydrochemical compositions were the water-rock interaction and contamination from sewage discharge and agricultural fertilizers. The major ions (F, HCO3) and trace element (As) in the shallow groundwater represented the natural origin, while the nitrate and sulfate concentrations were related to the application of fertilizer and sewage discharge in the facility agricultural area, which was mainly affected by the human activities. The values of pH, total dissolved solids, electric conductivity, and conventional component (K, Ca, Na, Mg, Cl) in shallow groundwater increased from grass land and cultivated land, to construction land and to facility agriculture which were originated from the combination sources of natural processes (e.g., water-rock interaction) and human activities (e.g., domestic effluents). The study indicated that both natural processes and human activities had influences on the groundwater hydrochemical compositions in shallow groundwater, while anthropogenic processes had more contribution, especially in the reclaimed water irrigation area.  相似文献   
923.
培养基种类和培养条件对白腐真菌生长和产酶特性的影响   总被引:9,自引:1,他引:8  
以白腐真菌(Phanerochaete chrysosporium)为研究对象,比较了该菌种在人工合成培养基和天然培养基中的生长和产酶特性,考察了竹子浸出液,pH,载体和抗生素等对白腐真菌在天然培养基中生长和产酶特性的影响.结果表明,天然培养基中白腐真菌的生物量、菌丝小球直径和木质素过氧化物酶(LiP)活性均大于人工培养基.以天然培养基为基础培养基,加入竹子浸出液可以促进白腐真菌的生长和提高木质素过氧化物酶活性;较低pH(4.5)条件下菌丝小球直径较小;载体的加入使得菌体以附着形式生长;抗生素两性霉素B对白腐真菌的生长和产酶的影响存在阈值,当ρ(两性霉素B)超过50 mg/L时,白腐真菌的生长和产酶受到明显的抑制.   相似文献   
924.
壳聚糖改性凹凸棒土对重金属离子的吸附   总被引:3,自引:0,他引:3  
采用浸渍法将壳聚糖负载在凹凸棒土上,制备了改性的凹凸棒土。用该吸附剂吸附溶液中Pb^2+,Cd^2+的实验结果表明:未负载壳聚糖时,凹凸棒土对Cd^2+的吸附率为55%;当负载壳聚糖的质量分数为0.04时,凹凸棒土对Cd^2+的吸附率达最大值(为91%),对Pb2+的吸附率也达最大值(为75%)。其吸附行为符合Langmuir等温吸附方程和Freundlich等温吸附方程。该吸附剂可重复使用。  相似文献   
925.
酸析-Fenton试剂氧化-混凝法处理制浆废水   总被引:1,自引:1,他引:0  
用酸析-Fenton试剂氧化-混凝法对自偶氧化清洁制浆废水进行预处理,考察了各种因素对处理效果的影响。最佳处理条件:酸析时的废水pH为3.0;酸析后上层清液无需调节pH,加水稀释至COD为2000mg/L后进行Fenton试剂氧化,H2O2加入量为84.56mmol/L,FeS04加入量为8.44mmol/L,反应时间60min;混凝时Ca(OH):加入量为2g/L。最终出水的COD为577.20mg/L(COD去除率为71.14%),色度为36倍,pH为8.60。  相似文献   
926.
水解酸化-SBR工艺处理饮料生产废水   总被引:1,自引:0,他引:1  
介绍了水解酸化+SBR工艺处理饮料生产废水的工艺设计和运行效果。该工艺具有处理效果好、低能耗、易管理等特点。在进水CODCr为2000~4000mg/L,BOD5为1000~2000mg/L的条件下,经过该系统处理,出水CODCr保持在130mg/L以下,BOD5保持在25mg/L以下,出水水质达到(GB8978-1996)《中华人民共和国国家标准污水综合排放标准》的Ⅱ级标准。  相似文献   
927.
结合Microsoft Visual Basic(VB)语言的编程特点,探讨了大气环境影响评价计算机软件系统的理论基础、设计思想和应用程序编制的实现方法,编制了专门处理大气扩散模式浓度计算的应用程序,避免了大量繁杂的手工计算工作,使计算快速、准确,提高了环境影响评价工作的质量.  相似文献   
928.
Many plant species defend themselves against herbivorous insects indirectly by producing and releasing induced volatiles to attract natural enemies of the herbivores. In this paper, we consider the recruitment of natural enemies attracted by plant-induced volatiles and introduce the An–Liu–Johnson–Lovett model into the Lotka–Volterra model in an attempt to add this missing vital link in tritrophic interaction. Increase in attraction strength of plant-induced volatiles to the natural enemy leads to high fluctuation amplitude of plant biomass and herbivore population. When the attack strength of natural enemies reaches a certain level, fluctuation amplitude of plant biomass and herbivore population will decrease and plant biomass will approach to its environmental carrying capacity. The simulation demonstrates that plant volatile compounds induced by insects have led to the introduction of a third tritrophic level, e.g., natural enemies, into the plant–herbivore system, resulting in the coexistence of plants, insects, and natural enemies during the evolution process.  相似文献   
929.
The Danjiangkou reservoir lies in the upper Hanjiang basin and is the source of water for the Middle Route Project (MRP) under the South-to-North Water Transfer Scheme (SNWT) in China. The eco-environment of water resource areas plays an important role in water conservation and purification and would have significant implications for the economic prosperity in Hanjiang basin as well as for the SNWT. Focusing on the Danjiangkou Reservoir Area (DRA), this study established an environmental information system database. Based on the database, an eco-environmental vulnerability assessment method using integrated fuzzy AHP (FAHP) and GIS was developed for the DRA. According to eco-environmental conditions and anthropic effects, vulnerability was classified into five levels: potential, light, medium, heavy and very heavy. The eco-environmental vulnerability distribution and major problems of the eco-environment were analysed and discussed. The results indicated that eco-environmental vulnerability in the DRA was moderate overall. Regions with lower eco-environmental vulnerability were located in Qinling Mountain area in the northwest, Daba Mountain area in the south and the area immediately surrounding Danjiangkou Reservoir in the east. Two regions with very high eco-environmental vulnerability were located in the north of Danjiangkou Reservoir in Henan province and in the western part of Shanxi province. On the basis of analysis of distribution of the different factors of eco-environmental vulnerability, different environmental protection measures were proposed for different areas. This study demonstrated that the proposed method was an effective approach for the assessment of environmental vulnerability. The results gained closely reflected the reality of the eco-environmental vulnerability of the DRA.  相似文献   
930.
氯代芳香化合物的KOW与对数拓扑指数和路径指数的相关性   总被引:3,自引:1,他引:2  
李良超  尹业高 《环境化学》1999,18(6):532-537
本文用1gKow表征氯代芳香化合物的生物降解能力,并分别以对数拓扑指数(LTI)和路径指数(PI)为自变量,建立了新的预测模型。结果表明,回归方程的预测值与实验值十分吻合,相关系数接近于1,平均标准偏差小于0.1。  相似文献   
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