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1.
介绍了测试舱的研制意义、测试舱构造和温度控制部分,以及空气交换、循环控制,空气净化装置和温度、湿度、流速显示装置等.通过实验,对测试舱的温度控制,空气净化系统检验,空气交换、循环的检验,释放甲醛平衡点的快速判断和测试舱的比对等运行技术指标进行了论证、优化.结果表明,简易的室内装饰装修材料测试舱对主要运行参数可以自动运行与控制,运行情况满足国家标准方法的技术指标要求,与同类商品化测试舱相比,误差在2%左右.  相似文献   

2.
选取2001—2014年的相关数据,采用环境库兹涅茨曲线(EKC曲线)模型和物理学的区域重心模型,分析了江苏省工业发展与大气污染物排放的时空演变关系。结果表明,2001年以来,随着工业总产值的增加,工业废气排放量呈现增加的趋势,虽然增加幅度有所减缓,但是拐点还未出现,而SO_2和烟粉尘排放强度已经跨过EKC曲线高峰进入二者协调发展的新阶段。时空演变关系表明,工业总产值和污染物排放强度重心均有较大的移动,并且二者的移动方向呈现相反的趋势,而SO_2和烟粉尘排放强度重心的移动方向具有相同的趋势,并且移动幅度接近。指出,当污染物减排到一定程度时,新的技术和政策措施必须同步发展,才能使污染物排放得到进一步控制,最终进入第五个阶段。  相似文献   

3.
正不久前网上关于农夫山泉的"标准门"被炒得沸沸扬扬,媒体报道农夫山泉标准不如自来水,再次触发了公众对饮用水水源的重新思考。不管是商家的竞争,还是水质的问题。水被誉为生命之源,可见其重要性,尤其饮用水的安全,关乎民生大计,绝不容忽视。近些年,我国农村的大多数生活污水直接排放,造成河流、水塘污染,不仅影响农村居民居住环境,而且严重威胁到了农村居民的身体健康。农村普遍存在基础设施建设薄弱、排水系统和污水处理建  相似文献   

4.
日本城市环境监测技术系统运营管理研究与借鉴   总被引:1,自引:3,他引:1  
日本城市环境监测技术系统管理经历多年探索和总结,形成了成熟的运营模式,对我国现行技术系统的管理实践极有借鉴价值.目前环保部门在相应的管理、技术和人才等方面准备不足,面对社会专业化公司的参与,在管理和运营中暴露出一些问题,比较和借鉴国外市场化运营理念,将促进我们管理思路的创新.  相似文献   

5.
推进环境监测转型 为探索环保新道路提供技术支撑   总被引:1,自引:0,他引:1  
环境保护工作是全面落实贯彻科学发展观的重要措施,是科学发展的具体体现.环境监测是环境保护工作的基础,是环境管理的组成部分,对于摸清环境状况,促进环境保护事业的发展,满足广大公众的环境知情权,建设和谐社会具有重要作用.  相似文献   

6.
对土壤的前处理进行了研究,通过一系列的实验验证,给出了土壤中砷、锑和汞的监测分析方法,采用王水消解,硫脲还原,蒸气发生连续进样,运用原子荧光光谱法进行测定,得到了令人满意的结果.  相似文献   

7.
重庆市区灰霾天气变化及特征分析   总被引:1,自引:0,他引:1  
分析了近15年重庆市区灰霾的时间变化特征以及主要大气污染物与能见度的相关性。1997—2012年,灰霾天气占41.2%,发生天数没有明显变化,严重程度有所减缓。灰霾在冬季发生的天数最多,持续时间长,且容易发生重度的持续灰霾。夏季灰霾天数最少,程度最轻。PM10、PM2.5、SO2、NO2浓度随灰霾的加重而增加,其中PM2.5浓度增幅最大,O3浓度随灰霾的加重而降低。灰霾对能见度的影响大于降水天气对其的影响。灰霾天气下能见度受PM2.5的影响较大,非灰霾天气下,能见度主要受O3的影响。  相似文献   

8.
环境问题的日渐突出促使我国环境保护事业不断发展,近年来,环境执法在环境保护中发挥着越来越重要的作用,也面临着来自内部和外部的诸多挑战。本文针对我国环境执法难的现实,立足执法三要素(法律、执法者及执法对象),坚持内外因相结合,剖析了执法难的症结,提出了具体的对策。  相似文献   

9.
正中国新闻网消息日前,世界银行在北京发布了《中国可持续性低碳城市发展》。该报告称,中国的城市走低碳发展之路,有助于实现国家降低单位G D P能源强度和碳强度的目标,同时更加宜居,效率更高,更有竞争力,最终实现可持续发  相似文献   

10.
新京报消息昨日,400 km之外的国际空间站发布了《地球生命力报告2012》,报告称,过去40年,地球生命力下降了28%,处于"很不健康"的状态。昨日,兼任世界自然基金会(WWF)推广大使的欧洲航天局宇航员安德鲁.库佩斯从国际空间站向全球发布了该组织  相似文献   

11.
本文阐述了在我国共860多个土壤样品、41种土类中的48种元素背景值调查研究中,元素含量差异的来源并估计了各部分来源的差异所占比例;同时采用单因素方差分析法,研究了土壤类型对48种元素背景值的影响。结果表明,土壤背景值数据的伯差主要来源于样品本身固有的差异;常量元素的采样偏差大于分析测试过程产生的偏差;而微量元素的分析测试偏差大于采样偏差。  相似文献   

12.
北京市主要水污染物排放特征及水质改善对策   总被引:3,自引:1,他引:2  
污染排放信息是环境决策的重要依据。分析了北京市水环境质量的现状,基于最新源排放清单,解析北京市当前主控污染物COD、氨氮排放的结构特征和空间特征,以期为北京市开展基于流域综合治理的水污染控制和水环境管理提供依据。按照工业源、农业源、生活源和集中处理设施的环境统计口径,2013年,COD、氨氮的排放构成分别为2.7%、37.1%、35.0%、25.3%和1.5%、20.1%、54.8%、23.6%。其中,农业源中畜禽养殖排放是主要来源,COD、氨氮总排放分别占农业源总排放量的94.7%和87.0%。在北京市五大水系中,北运河流域排放量最大,COD、氨氮排放量分别占全市总排放量的53.3%和57.4%。为改善北京市水环境质量,建议从加快污水处理厂提标改造、推动面源污染治理、加强水利联通、合理规划城市规模布局等4个方面入手。  相似文献   

13.
通过对土层中石油烃类污染物索氏抽提流程的改进 ,实现蒸馏氯仿的回收与再利用。实验结果表明 ,用改进索氏抽提流程测的有机物含量与传统的流程相比 ,所减少的石油烃类物质损耗占总石油物质含量的 1 0 % ;同时 ,蒸馏回收的氯仿的 70 %可以重新用于索氏抽提 ,由此产生的误差小于 1 % ,不会影响残油微生物降解试验的分析精度 ,具有资源回收与保护环境的双重效应  相似文献   

14.
室内装修后苯、甲苯、二甲苯和甲醛污染调查   总被引:10,自引:0,他引:10  
对青岛市装修后房屋空气进行调查,按照装修时间分装修时间1周~6个月、7个月~1年、1年以上三个组,对三组室内空气中苯、甲苯、二甲苯和甲醛进行监测,发现室内装修时间短时苯、甲苯、二甲苯的浓度较高,甲醛浓度较低;随装修时间增长,苯、甲苯、二甲苯的浓度很快降低,但甲醛的浓度呈升高趋势。  相似文献   

15.
The aim of the study was to determine the extent of heavy metal pollution in the vicinity of a lead battery manufacturing plant in the Czech Republic, both in the general environment and within homes. Topsoils (0–5 cm) were sampled from 100 sites along 4 transects which crossed the battery factory, the town centre and outlying rural areas. Housedust samples were collected from 15 plant-workers' homes and 15 non plant-workers' homes located at various distances from the factory. Samples were analysed for levels of Pb, Zn, Cd, Cu, As and Sb, using ICP-AES. Soil concentrations of Pb, Cd, As and Sb peaked at the perimeter fence of the battery factory with Pb levels of up to 12 650 g g> -1. Concentrations of these metals decreased exponentially within 500 m of the plant. Whilst the battery factory does appear to be a source of all the metals with the exception of Zn, emissions do not appear to be transported to any great extent over distances of more than 0.5 km. Topsoil and housedust concentrations of Pb, Zn, Cd, Cu, As and Sb in the general Mlada Boleslav area do not appear to be significantly different from those recorded in a large scale survey of urban soils in the United Kingdom. A comparison of housedust Pb concentrations in homes of plant workers and non-plant workers suggests that there may be a small input of Pb into the home environment by battery plant employees.  相似文献   

16.
从新疆某地典型城-郊-乡梯度带采集了77个表层(0~20 cm)土壤样品,基于GIS技术与多元统计分析方法,研究各梯度带表层土壤中Hg、As、V、Co、Ni、Cu、Zn、Cd、Pb和Sb等10种微量元素的空间分布特征与主要来源。结果表明:Hg元素在城区、郊区和乡村表层土壤中的平均含量均超出研究区土壤背景值,As元素在城区和郊区表层土壤中的平均含量超出背景值,Zn和Pb元素在城区表层土壤中的平均含量超出背景值,其余元素在3个梯度带表层土壤中的平均含量均低于相应的背景值。研究区表层土壤中,V、Co、Ni、Zn、Cd、Pb和Sb等7种元素的空间分布格局基本相似,均呈现沿城市化梯度带分布的地带性格局;As、Cu和Hg等3种元素的空间分布呈现岛状格局。来源分析结果表明,各梯度带表层土壤中的微量元素的来源各不相同。  相似文献   

17.
The assessment of marine pollution due to metals was made for surficial sediments sampled from 20 sites along Mediterranean coast of Egypt. The samples were dried, acid digested and analyzed for leachable and total heavy metal contents (Cd, Co, Cr, Cu, Fe, Mn, Ni, Pb, and Zn) by flame atomic absorption spectrophotometer (air–acetylene) with deuterium background correction. Evaluation of the heavy metals pollution status was carried out using enrichment factors (EFs), the effect range-low (ERL) and the effect range-median (ERM). The study showed high concentrations of Cd, Co, Pb, Ni and moderate concentrations of Cr, Cu and Mn were contaminated in the sediments of studied sites. The results of Spearman correlation, factor and cluster analysis of the heavy metals analyzed in the collected sediment were discussed. The main source of contamination is the offshore oil field and industrial wastes, which arise due to the ineffective and inefficient operation equipments, illegal discharge and lack of supervision and prosecution of offenders.  相似文献   

18.
The rapidly developing Asian countries may face threatening environmental contamination, that however remains largely unassessed. We studied persistent trace elements in three wetlands, Poyang Lake, relatively unpolluted, and Tai Lake, and Pearl River Delta, selected as hotspots of pollution in Central China. We adopted as indicator the Little Egret, a widespread colonial waterbird, and during 1999 and 2000 we collected and analysed the same samples as for a parallel study we conducted in Pakistan, e.g. eggs, body feathers of chicks, prey spontaneously regurgitated by the chicks, and sediments at the areas most used by foraging egrets. The levels of trace-metals at our three study areas were similar, or within the range, of those found in the few other studies for East Asia, with few exceptions. The concentrations of the various elements were below the threshold that may affect the survival or reproduction of the birds, and even the highest concentrations relative to background, i.e. Se in eggs, and Hg in feathers at Pearl Delta, do not pose toxic hazards. In sediments, the levels of trace elements were lower than the critical levels assumed for contaminated soil, except for alarming high levels of As at Poyang. These results do not confirm our expectation, that Poyang was relatively uncontaminated, while Tai and Pearl were polluted. Although trace metal concentration differed significantly among the three study areas, these differences were minor and were not consistent among elements and samples. The bioaccumulation ratios from sediments through prey, feather and egg, were consistent with our previous findings for Pakistan. Only Hg exhibited high bioaccumulation, while Se and Zn had low accumulation, and the other elements no accumulation. This reasserts that feathers of predators such as egrets, may be more sensitive indicators of environmental contamination for the elements subject to bioaccumulation, whereas the sediments or the organisms low in the food chain are better indicators for the other elements.  相似文献   

19.
Environment Canada and the Québec Department of the Environment, partners in the St Lawrence Vision 2000 Action Plan, set out to prepare a compendium of knowledge of the flora and fauna of the St Lawrence and to identify potential conservation sites. The resulting Portrait is an Internet site that presents the current knowledge base of the river's ecological and biological diversity (http://lavoieverte.qc.ec.gc.ca/faune/biodiv/index.html). The Portrait provides information on over 5,000 species of flora and fauna. On the website, you will find a detailed ecological analysis of the richness, rarity and vulnerability of several broad groups of plant and animal species. Furthermore, you will find a list of species for each of the 700 survey units and a distribution map for 2,500 species recorded along the St Lawrence., in atlas form, along with a detailed conservation plan. The plan encompasses the most unique and heterogeneous landscapes of the St Lawrence, some of which have no protection at present. The Portrait provides an overview of the sites that are currently protected by public agencies and private-sector organisations and identifies new sites of interest for conserving biodiversity and protecting species at risk. This paper exposes the content of this extensive compendium on the biodiversity of the St. Lawrence. For conciseness, it presents some of the analyses conducted on birds to illustrate a few of the analytical approaches that were used. Then, the information on species richness and concentration areas for priority species of vascular plants, breeding birds and herpetofauna will serve to identify the terrestrial sites of significance for biodiversity. Finally, a similar approach having been applied to the aquatic environnement, we will conclude with a conservation plan that identifies the terrestrial and aquatic ecosystems, and the geographic sites where the most important elements of St. Lawrence biodiversity are concentrated. Our analysis of the biodiversity of the most thoroughly studied taxa of the St. Lawrence clearly shows the importance of wetlands, particularly those located at the mouths of rivers or within archipelagos or delta complexes, such as the groups of islands and channels found at both ends of the Montréal Archipelago. These aquatic landscapes are sites of intense biological production, combining in a small geographical area spawning, nursery and feeding grounds for a large number of fish species and breeding, rearing and foraging areas for aquatic birds. Variable flooding conditions, associated with seasonal flooding or daily tidal fluctuations, create a complex mosaic of wetland and aquatic habitats. Although wetlands occupy only a small area in comparison with terrestrial habitats, they support a large number of rare plant and animal species in relation to their size. At present, 10% of the vascular flora and 27% of the herpetofauna of the St. Lawrence are at risk. In the case of reptiles and amphibians, the situation is especially worrisome because nearly all of the most threatened species live in a narrow band along the river corridor. Not only is this the sector that is under the greatest pressure from human development, very little public land remains here, making it difficult to create protected areas. Increased participation by non-governmental organisations and individuals, through private stewardship arrangements, is an essential precondition for completing the network of conservation areas in this part of the St. Lawrence. Along the estuary and the Gulf, habitat integrity has not been affected as much by the expansion of Québec's human population. This is a vast territory, and sites have been identified with a view to making up for the deficiencies in the present network of protected sites in terms of representing biodiversity.  相似文献   

20.
Vassova lagoon is a typical Mediterranean (small, shallow, micro-tidal, well-mixed) coastal lagoon, receiving limited seasonal freshwater inflows from direct precipitation and underground seepage. An intensive study was carried out in order to quantify the mechanisms responsible for the intra-tidal and residual transport of water, salt, nutrients and chlorophyll at the mouth of this lagoon and to assess the lagoon's flushing behavior. Results indicated that although the system is micro-tidal, tidal effects appeared to be the dominant factor for the longitudinal distribution of physical and chemical parameters, while the associated residual flow is also important and serves as a baseline measure of overall circulation. However, analysis of the net longitudinal currents and fluxes of water, salt and nutrients revealed the importance of non-tidal effects (wind effect and precipitation incidents) in the mean tidal transport. It is shown that the Eulerian residual currents transported water and its properties inwards under southern winds, while a seaward transport was induced during precipitation incidents and northern winds. The Stokes drift effect was found an order of magnitude lower than the Eulerian current, directed towards the lagoon, proving the partially-progressive nature of the tide. Nutrients and chlorophyll-α loads are exported from the lagoon to the open sea during the ebb phase of the autumn and winter tidal cycles, associated with the inflow of nutrient-rich freshwater, seeped through the surrounding drainage canal. The reverse transport occurs in spring and early summer, when nutrients enter the lagoon during the flood tidal phase, from the nutrient-rich upper layer of the stratified adjacent sea. Application of a tidal prism model shows that Vassova lagoon has a mean flushing time of 7.5 days, ranging between 4 to 18 days, affected inversely by the tidal oscillation.  相似文献   

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