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171.
Since the majority of schools are housed in buildings dating from the 1960s and 1970s, a comprehensive construction and renovation program of school buildings has been carried out to improve the educational conditions in Korea. However, classrooms and computer rooms, with pressed wood desks, chairs and furnishings, as well as construction materials, might have negative effects on the indoor air quality. Furthermore, most schools have naturally ventilated classrooms. The purpose of this study was to characterize the concentrations of different indoor air pollutants within Korean schools and to compare their indoor levels within schools according to the age of school buildings. Indoor and outdoor air samples of carbon monoxide (CO), carbon dioxide (CO(2)), particulate matter (PM(10)), total microbial count (TBC), total volatile organic compounds (TVOCs) and formaldehyde (HCHO) were obtained during summer, autumn and winter from three sites; a classroom, a laboratory and a computer classroom at 55 different schools. The selection of the schools was based on the number of years since the schools had been constructed. The problems causing indoor air pollution at the schools were chemicals emitted by building materials or furnishings, and insufficient ventilation rates. The I/O ratio for HCHO was 6.32 during the autumn, and the indoor HCHO concentrations (mean = 0.16 ppm) in schools constructed within 1 year were significantly higher than the Korean Indoor Air Standard, indicating that schools have indoor sources of HCHO. Therefore, increasing the ventilation rate by means of a mechanical system and the use of low-emission furnishings can play key roles in improving the indoor air quality within schools.  相似文献   
172.
We conducted a natural resource assessment at two national parks, New River Gorge National River and Shenandoah National Park, to help meet the goals of the Natural Resource Challenge—a program to help strengthen natural resource management at national parks. We met this challenge by synthesizing and interpreting natural resource information for planning purposes and we identified information gaps and natural significance of resources. We identified a variety of natural resources at both parks as being globally and/or nationally significant, including large expanses of unfragmented, mixed-mesophytic forests that qualify for wilderness protection, rare plant communities, diverse assemblages of neotropical migratory birds and salamanders, and outstanding aquatic recreational resources. In addition, these parks function, in part, as ecological reserves for plants in and wildlife. With these significant natural resources in mind, we also developed a suite of natural resource management recommendations in light of increasing threats from within and outside park boundaries. We hope that our approach can provide a blueprint for natural resource conservation at publically owned lands.  相似文献   
173.
活性炭烟气脱硫技术研究新进展   总被引:3,自引:0,他引:3  
研制了新型活性炭脱硫剂-脱硫活性碳纤维。研究表明,脱硫活性碳纤维由于含碳量高、比表面积大、微孔丰富、孔径分布窄、有较多适于吸附SO2的表面官能团,因而吸附能力及吸附、脱附速度显著大于普通活性炭。在相同工艺条件下,脱硫活性碳纤维吸附容量为粒状疾性炭的4-5倍,空速粒达活性炭的10倍。采用活性碳纤维脱硫可比普通活性碳脱硫剂用量成倍减少。另外,由于活性碳纤维阻力小,系统能耗可显著降低。活性碳烟气脱硫采用  相似文献   
174.
基于DPSIR模型的天津滨海新区环境风险变化趋势分析   总被引:5,自引:0,他引:5  
考虑区域环境污染事件的形成机制,根据驱动力-压力-状态-影响-响应(DPSIR)模型框架,提出系统度量区域环境风险变化趋势的指标体系和评价模型,并对天津滨海新区工业化进程中突发性环境污染事件引发的环境风险变化趋势进行了评估. 结果表明:天津滨海新区2007,2015及2020年环境风险分别为0.487,0.508和0.367,分别处于警戒状态、较差状态和警戒状态,说明滨海新区环境风险形势比较严峻,需要进一步采取更有效的响应对策.   相似文献   
175.
为研究怀洪新河太湖新银鱼国家级水产种质资源保护区(以下简称保护区)水域浮游动物的群落结构及其与水环境因子的关系,于2014年6月(夏季)在怀洪新河进行采样分析,并对调查区域内的浮游动物及主要环境因子进行了主成分分析(PCA)和典范对应分析(CCA)。结果表明,保护区河段属中营养型河流;保护区浮游动物有4门24属33种,其中轮虫类最多,为11种(占33.33%),其次为原生动物和桡足类,均为8种(占24.24%),最少的为枝角类6种(占18.18%);保护区浮游动物细胞密度平均为1.82×10~4ind./L,生物量平均为2.45mg/L;水温和氨氮是影响水体环境的关键因子;水温、总氮、浊度、氨氮、高锰酸盐指数(COD_(Mn))和pH是影响浮游动物群落结构的主要驱动因子。  相似文献   
176.
通过构建新型城市化和生态环境指标体系,综合运用熵权法和协调发展度模型,比较分析2004~2013年中部地区6个省会城市新型城市化和生态环境的协调发展状况。结果发现:10年期间,6市的新型城市化与生态环境的发展水平及二者的协调发展度都呈现整体上升趋势;武汉市的协调发展水平在总体上处于首位,是中部6省会唯一的协调发展类城市,而其余5市的协调发展水平整体偏低。实现新型城市化与生态环境的协调发展,重点在于保持新型城市化的健康良性发展趋势,同时还应提高生态环境水平,减少生态环境压力,增强环境治理强度,以保证生态环境可持续发展。  相似文献   
177.
滨海新区湿地生态系统服务功能价值评估   总被引:1,自引:0,他引:1  
滨海新区湿地类型多样,作为滨海新区生态环境与景观生态的基质,对其区域生态、景观生态及经济发展具有重要影响。以滨海新区湿地为研究对象,在实地调查的基础上,综合采用市场价值法、影子工程法、条件价值法等评估方法,对其生态系统服务功能价值进行估算。结果表明,滨海新区湿地生态系统服务功能价值为4 276.77亿元,其中直接使用价值、间接使用价值和非使用价值分别为412 594万元、40 411 851万元和1 943 256万元。因此,滨海新区湿地对维持当地可持续发展具有举足轻重的作用,在滨海新区湿地资源管理和开发利用的过程中,应充分发挥湿地资源的生态功能,促进区域经济的可持续发展。  相似文献   
178.
Sows housed in stalls are kept insuch extreme confinement that they are unableto turn around. In some sectors of the porkindustry, sows are subjected to this degree ofconfinement for almost their entire lives(apart from the brief periods associated withmating). While individual confinement isrecognized by farmers and animal welfarecommunity organizations alike, as a valuabletool in sow husbandry (to mitigate againstaggression), what remains questionable from ananimal welfare point of view is the necessityto confine sows in such small spaces.In 2001, the Australian Journal ofAgricultural Research published a reviewarticle on the science associated with the useof the sow stall, and claimed that ``noscientific evidence to support therecommendation in the Code of Practice advisingagainst housing of sows in stalls followed byhousing in crates' (Barnett et al., 2001, p. 21).If all the available scientific publications onthe animal welfare implications of sow stallsare consulted (many of which did not feature inthe above review), then one will indeed findscientific evidence to support recommendationsagainst the housing of sows in stalls. Becausethere is science on both sides of this policydivide, the argument to defend the use of sowstalls, therefore, is not one of science vspublic opinion, but one of ethics.An analysis of the scientific argumentsagainst the use of the sow stall should be usedto encourage ethical debate on this issue. Asan ethical debate, the issue of the use of thesow stall can then focus on the degree ofsuffering we as a society are willing totolerate in agricultural practices, and theanimal welfare costs associated with extremeeconomies of scale in sow stocking rates,rather than get bogged down in red herringdebates over whether there is any suffering atall.  相似文献   
179.
ABSTRACT: Autochthonous energy input, in the form of periphyton production and growth, was studied before and after partial logging of the watershed surrounding School Brook, a small tributary of the Aroostook River, Maine. Due to infection by the spruce budworm (Chiristoneura fumiferana), the buffer strip on one bank of the stream was logged and only limited riparian vegetation was left. Though impacts in subsequent years are unknown, the effect of the logging on the periphyton community was insignificant during the nine months following cutting, seemingly due to several factors. Because only 5 percent of the canopy was actually removed, the intensity of available light changed little. Small springs in the area helped maintain a stable thermal regime, and only a small portion of the low gradient watershed was actually logged. Consequently, the nutrients reaching the stream did not change. The relatively low concentrations of nitrates (< 0.3 mg/l) and phosphates (< 10 μg/l), both before and in the first nine months after logging, reflect the limited autochthonous input, thereby reducing the effect of this limited cutting on the stream community.  相似文献   
180.
以沪东造船厂、上海炼油厂和上海高桥巴斯夫分散体有限公司等为例,阐述了浦东新区企业实施清洁生产和通过ISO14001环境管理体系认证的实践,地方环保部门在推行中所起的积极作用,并提出了建议。  相似文献   
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