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51.
以2008年北京奥运会为例,通过入境游客行为调查分析奥运会举办对入境游客旅游动机的影响。结果表明,影响入境游客旅游动机的因素主要有限制性因子、社会心理因子和文化教育因子,其中社会心理因子和文化教育因子与北京奥运会显著相关;入境游客的年龄、学历和家庭结构与奥运会举办呈现负相关;游客的年龄、学历、年收入和家庭结构等变量受奥运会影响显著,提出了相应的营销策略。  相似文献   
52.
青奥会前后南京PM2.5重金属污染水平与健康风险评估   总被引:2,自引:5,他引:2  
人类活动对大气环境的影响已成为人们关注的焦点.于青年奥林匹克运动会(青奥会,Youth Olympic Games)召开前后(2014年4~9月)动态监测南京大气中PM_(2.5)及其6种重金属质量浓度和污染特征,并分析其健康风险.结果表明,观测期间PM_(2.5)质量浓度变化范围为26.39~80.31μg·m~(-3),青奥会前的4、5和7月大气中PM_(2.5)质量浓度均达到国家空气质量二级标准(24 h质量浓度限值75μg·m~(-3)),青奥会期间达到国家空气质量一级标准(24 h质量浓度限值35μg·m~(-3)).青奥会结束后,空气污染出现反弹,大气PM_(2.5)质量浓度平均值为76.14μg·m~(-3).观测期间大气PM_(2.5)中重金属离子质量浓度的变化特征并不一致,主成分分析表明,污染物源排放是影响PM_(2.5)重金属离子质量浓度变化最重要因素.青奥会期间PM_(2.5)及重金属离子质量浓度均降至观测期间最低值,这与召开青奥会所采取的一系列政策干预减排措施发挥作用有关.PM_(2.5)中Cd、Cu、Ni、Pb通过呼吸和皮肤暴露的健康风险值均在可接受水平范围内,而Cr存在较大的致癌风险;Mn通过呼吸暴露对成年男性造成较大的非致癌风险;同时PM_(2.5)中6种重金属通过皮肤暴露对儿童也造成较大非致癌风险.  相似文献   
53.
简述了南京市废气重点污染源在线监测系统的组成和工作原理。根据2014年南京青奥会废气重点污染源环境临时管控要求,利用在线监控点位对7月份(青奥会前)和8月份(青奥会期间)重点废气污染源在线监测数据进行了统计分析。结果表明,青奥会期间南京市管控废气重点污染源的SO2和NOX排放量虽有个别企业出现增加,但整体排放量均有所降低,环境空气中SO2和NOX的平均值也有所降低,基本达到了临时管控要求。  相似文献   
54.
车辆限行前后奥运场馆附近空气中苯系物污染特征与来源   总被引:1,自引:1,他引:1  
在"好运北京"体育赛事车辆限行前后对北京奥运场馆,即四环路健翔桥附近空气中的6种苯系物进行了连续监测。监测结果显示,被测空气的苯系物中甲苯所占比例最大,为32.1%~42.5%,限行后总苯系物平均质量浓度降低了近47%。车辆限行前后,苯系物呈现类似的日变化规律,在交通早、晚高峰时出现峰值。限行前苯系物处于累积状态,日最高值出现在18点,限行后苯系物处于扩散状态,日最高值出现在8点。苯系物来源解析表明,整个交通管制期间苯/甲苯浓度的比值为0.49~0.55,且各苯系物具有良好的相关性,证明被测空气中苯系物具有良好的同源性,均来自汽车尾气。限制车流量可有效降低空气中苯系物浓度。  相似文献   
55.
为了评估2008年奥运会期间北京市机动车控制措施效果,对不同控制措施阶段北四环道路的气态污染物进行监测,并同步采集车流与气象信息.基于监测结果归纳气态污染物特征,分析控制措施的影响,并计算高峰小时与日间小时平均污染物人体吸入剂量.结果表明,控制措施全面实施期间(Ⅲ阶段)北四环路日间平均车流量下降约22%,其中轻型车流量降低约43%.与之相对应,北四环CO、NOx、NO2的浓度水平范围分别是0.10~3.94,0.002~0.139,0.002~0.099mg.m-3,较奥运前(2008年5月)监测浓度显著下降.其中,奥运赛事期间(Ⅲ-2阶段)CO、NOx、NO2平均浓度降幅最大,分别达到63%,71%和70%.奥运期间(Ⅲ阶段)CO与NOx的单人与总人群的高峰小时和日间平均小时吸入剂量较奥运前(2008年5月)均有显著下降,其中CO单人高峰小时与日间小时平均吸入剂量降幅分别是63%和81%;NOx单人高峰小时与日间小时平均吸入剂量降幅分别是58%和55%.区域总人群的吸入量也同比例下降.奥运期间严格的交通控制措施大幅削减了机动车污染物排放量,从而降低了道路交通环境机动车尾气污染引起的人体吸入剂量.  相似文献   
56.
In order to investigate the air quality and the abatement of traffic-related pollution during the 2008 Olympic Games, we select 12 avenues in the urban area of Beijing to calculate the concentrations of PM10, CO, NO2 and O3 before and during the Olympic traffic controlling days, with the OSPM model.Through comparing the modeled results with the measurement results on a representative street, the OSPM model is validated as sufficient to predict the average concentrations of these pollutants at street level, and also reflects their daily variations well, i.e. CO presents the similar double peaks as the traffic flow, PM10 concentration is influenced by other sources. Meanwhile, the model predicts O3 to stay less during the daytime and ascend in the night, just opposite to NO2, which reveals the impact of photochemical reactions. In addition, the predicted concentrations on the windward side often exceed the leeward side, indicating the impact of the special street shape, as well as the wind.The comparison between the predicted street concentrations before and during the Olympic traffic control period shows that the overall on-road air quality was improved effectively, due to the 32.3% traffic flow reduction. The concentrations of PM10, CO and NO2 have reduced from 142.6 μg m−3, 3.02 mg m−3 and 118.7 μg m−3 to 102.0 μg m−3, 2.43 mg m−3 and 104.1 μg m−3. However, the different pollutants show diverse changes after the traffic control. PM10 decreases most, and the reduction effect focusing on the first half-day even clears the morning peak, whereas CO and NO2 have even reductions to minify the daily fluctuations on the whole. Opposite to the other pollutants, ozone shows an increase of concentration. The average reduction rate of PM10, CO, NO2 and O3 are respectively 28%, 19.3%, 12.3% and −25.2%. Furthermore, the streets in east, west, south and north areas present different air quality improvements, probably induced by the varied background pollution in different regions around Beijing, along with the impact of wind force. This finding suggests the pollution control in the surrounding regions, not only in the urban area.  相似文献   
57.
An observational study on trace gases and PM2.5 was conducted at three sites in and around Beijing, during the Olympic season from 2007 to 2009. Air quality improved significantly during the Olympic Games due to the special emission control measures. However, concentrations of the primary pollutants and PM were found to have risen significantly after the Games. Although the major O3 precursors (NOx and VOCs) were well controlled during the Olympic season, O3 was still found to be the highest in 2008, based on the data of ground-based observation. All this information suggests that while control of regional emissions for the Beijing Olympic Games did improved the air quality in Beijing, more efforts will be needed for the continuous improvement of regional air quality, especially for significant reductions of O3 and fine particulate pollution, and not only in Beijing, but also in the B eijing-Tianjin-Hebei region.  相似文献   
58.
Due to rapid urbanization and industrialization, heavy metals in road-deposited sediments (RDSs) of parks are emitted into the terrestrial, atmospheric, and water environment, and have a severe impact on residents' and tourists' health. To identify the distribution and characteristic of heavy metals in RDS and to assess the road environmental quality in Chinese parks, samples were collected from Beijing Olympic Park in the present study. The results indicated that particles with small grain size (< 150 μm) were the dominant fraction. The length of dry period was one of the main factors affecting the particle size distribution, as indicated by the variation of size fraction with the increase of dry days. The amount of heavy metal (i.e., Cu, Zn, Pb and Cd) content was the largest in particles with small size (< 150 μm) among all samples. Specifically, the percentage of Cu, Zn, Pb and Cd in these particles was 74.7%, 55.5%, 56.6% and 71.3%, respectively. Heavy metals adsorbed in sediments may mainly be contributed by road traffic emissions. The contamination levels of Pb and Cd were higher than Cu and Zn on the basis of the mean heavy metal contents. Specifically, the geoaccumulation index (Igeo) decreased in the order: Cd > Pb > Cu > Zn. This study analyzed the mobility of heavy metals in sediments using partial sequential extraction with the Tessier procedure. The results revealed that the apparent mobility and potential metal bioavailability of heavy metals in the sediments, based on the exchangeable and carbonate fractions, decreased in the order: Cd > Zn ≈ Pb > Cu.  相似文献   
59.
Each National Park Service unit in the United States produces a resources management plan (RMP) every four years or less. The plans commit budgets and personnel to specific projects for four years, but they are prepared with little quantitative and analytical rigor and without formal decision-making tools. We have previously described a multiple objective planning process for inventory and monitoring programs (Schmoldt and others 1994). To test the applicability of that process for the more general needs of resources management planning, we conducted an exercise on the Olympic National Park (NP) in Washington State, USA. Eight projects were selected as typical of those considered in RMPs and five members of the Olympic NP staff used the analytic hierarchy process (AHP) to prioritize the eight projects with respect to their implicit management objectives. By altering management priorities for the park, three scenarios were generated. All three contained some similarities in rankings for the eight projects, as well as some differences. Mathematical allocations of money and people differed among these scenarios and differed substantially from what the actual 1990 Olympic NP RMP contains. Combining subjective priority measures with budget dollars and personnel time into an objective function creates a subjective economic metric for comparing different RMP’s. By applying this planning procedure, actual expenditures of budget and personnel in Olympic NP can agree more closely with the staff’s management objectives for the park.  相似文献   
60.
奥运前期与奥运期间北京市大气细颗粒物特征比较分析   总被引:1,自引:4,他引:1  
利用城市生态系统研究站对北京市奥运前后(2008年6~9月)大气中细颗粒物(PM2.5)进行连续监测,获得不同阶段PM2.5日平均浓度的动态特征,分析气象因素、人为控制管理措施对颗粒物浓度的影响.结果表明,近北五环的生态中心站点(RCEES)颗粒物日均浓度平均值为0.067 mg.m-3,奥运期间的颗粒物浓度(0.060 mg.m-3)比奥运前期(0.081 mg.m-3)减少了约26%.而位于南二环市中心的教学植物园站点(JX)颗粒物浓度平均含量为0.078 mg.m-3.JX站点奥运期间的颗粒物浓度(0.069 mg.m-3)比奥运前期(0.095 mg.m-3)减少了约27%.各个阶段PM2.5的日变化都基本呈现双峰态势.第一个峰值出现在08:00~10:00左右,RCEES站点颗粒物浓度为0.068 mg.m-3,JX站点浓度值为0.089 mg.m-3;另一个峰值出现在晚20:00~22:00左右,RCEES和JX站点颗粒物浓度为0.079 mg.m-3和0.083 mg.m-3,这主要与上班交通高峰导致的尾气排放污染和道路扬尘污染等有关.研究气象参数发现奥运期间与奥运前期气象条件无显著差异,属于高温高湿风力不大的典型北京夏季天气条件.奥运期间颗粒物浓度与温度呈显著正相关(P<0.01),而与风速、相对湿度及降水相关性不显著(P>0.05).而连续多年大气污染综合治理措施和奥运空气质量保障措施的实施,产生了显著环境效益.在自然因素相差不大的条件下,人为控制因素对奥运期间颗粒物的下降起到主导作用.  相似文献   
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