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排序方式: 共有1002条查询结果,搜索用时 312 毫秒
871.
环境监测质量控制结果的几种评价方法探讨 总被引:1,自引:0,他引:1
从数理统计方法的角度出发,针对当前环境监测工作中常用的标准样品测定、比对监测和校准曲线等,探讨了质量控制数据的常用评价方法,为正确、客观评价质量控制水平提供必要的技术参考,使环境监测质量控制结论更加合理。 相似文献
872.
官金华 《中国环境管理干部学院学报》2013,(3):88-91
地方政府投融资平台在促进地方经济发展,推动城市化进程,应对国际金融危机等方面发挥了重要作用。但由于缺乏统一的管理,各地方政府投融资平台财务状况披露不公开、不透明,债务风险急剧扩大,引起了有关部门和专家学者的高度关注。各地方政府应将融资平台的各种信息,特别是债务情况,定期向主管部门报告,建立地方投融资平台信用评价方法,使得投融资平台朝着健康、良性的方向发展。 相似文献
873.
《Journal of environmental science and health. Part. B》2013,48(5-6):871-887
Abstract A lab-scale composting experiment was carried out using vegetable and flower stalks waste to study the effectiveness of ligno-cellulolytic microorganisms (LCMs) obtained from the previous isolation on composting process, especially on enhancement of biodegradation rate of these organic materials. The addition of LCMs to compost showed promised to be a valuable asset by rendering timely benefits in efficiency, maturity, and quality of the composting. This was evidenced by a significant increase of temperature, O2 consumption and CO2 emission, and population density of LCMs in compost mass compared with that of biotic (addition of culture of horse feces) and abiotic (1% molasses amendment) treatments, as well as control trial. The phytotoxicity assay showed that the substrate became mature after 60 days’ composting. The LCMs inoculation enhanced the biodegradation of the composting materials as evidenced by an increasing screening ratio (1.2 cm sieve pore) of 34.5% in the treated trail, compared with that of control, which elucidated that big advantage of adding selected inoculants over other treatment, and screening ratio is a reasonable index to compare the quality of different compost. However, the inoculation seemed to have no significant effect on the moisture content, pH, and the final organic carbon of the composting materials. 相似文献
874.
目的 找出太阳跟踪反射聚能户外加速曝晒方法的特点和价值。方法 基于几种典型的透明高分子材料试样,分别在佛罗里达典型亚热带潮湿环境自然曝晒、汽车外饰实验室氙灯加速耐候试验及亚利桑那太阳跟踪反射聚能户外加速曝晒黄变结果相关性、加速性和区分度的对比分析,来比较这几种试验方法的特点。结果 户外加速曝晒和自然曝晒的相关性高于氙灯加速试验和自然曝晒的相关性。与自然曝晒相比,户外加速曝晒的平均加速倍率及不同试样的加速倍率的相对差异明显小于氙灯加速试验。自然曝晒和户外加速曝晒的区分度也明显大于实验室氙灯加速试验。结论 户外加速曝晒方法较好地均衡了相关性、加速性、加速一致性及区分度,适合高分子材料的验证性试验。 相似文献
875.
Environmental impact assessment (EIA) procedures have been in existence in the People's Republic of China over the last decade.
The impetus for China's introduction of EIA was provided by the Environmental Protection Law of the People's Republic of China,
which was adopted by the Fifth National People's Congress in 1979. The EIA process, which is administrative and not statutorily
mandated, has been applied primarily to construction projects.
Four stages are typically involved in an EIA investigation: design of the investigation, evaluation of background environmental
quality, prediction of environmental impacts, and an assessment and analysis of the environmental impacts. A variety of approaches
is used for predicting and analyzing environmental impacts, ranging from ad hoc methods to fairly sophisticated mathematical
models. The results of the EIA investigation are compiled in an environmental impact statement, which is used as the basis
for decision making by personnel in environmental protection departments. The EIA process does not include provisions for
citizen notification or involvement.
Views differ concerning the effectiveness of the EIA program in protecting China's natural, social, and cultural environments.
Some hold that the EIA program has brought about improvement in environmental protection, while critics contend that the program
has had little effect in the prevention of pollution. However, most, if not all, observers seem to feel that the program should
be continued and improved. A major avenue for improvement is to place the evaluation of a particular project in a regional
context.
An earlier version of this paper was distributed at a workshop on Environmental Assessment Development Planning held in conjunction
with the VII Annual Meeting of the International Association for Impact Assessment, Brisbane, Australia, July 5–8, 1988. 相似文献
876.
如何提高COD比色法测试的精密度和准确度 总被引:3,自引:0,他引:3
针对COD比色法测试的技术特点,通过总结日常分析、验收考核中存在的经验和问题,给出了如何提高COD测试仪测量精密度、准确度的方法和仪器质量的核查方法。 相似文献
877.
Wang D Hao Y Wang K Zhao Q Chen D Wei Z Zhang X 《Environmental science and pollution research international》2005,12(5):247-250
Background As the sole freshwater subspecies of finless porpoise (Neophocaena phocaenoides), the Yangtze finless porpoise (N. p. asiaeorientalis)
lives only in the middle and lower reaches of the Yangtze River and its appended Poyang and Dongting Lakes. As a result of
human activity on the river, including over and illegal fishing, pollution, transportation and dam construction, the population
of Yangtze finless porpoises has been steadily and rapidly decreasing during the past several decades, which leads the animal
to be endangered.
Methods For saving this unique animal from extinction, three corresponding measures, in situ conservation, ex situ conservation,
and intensifying breeding research in captivity, were proposed and have been implemented since the 1980s.
Results After successfully rearing the animals in captivity for almost nine years, the first Yangtze finless porpoise was successfully
born in captivity on July 5, 2005. The calf is male, with a body length of 69cm. This is the first freshwater cetacean ever
born in captivity.
Conclusion The successful birth of this calf confirms that it is possible to breed the Yangtze finless porpoise in captivity. Furthermore,
this will greatly benefit the conservation efforts, and also greatly bolster our on-going efforts to study the reproductivebiology
of these animals.
Recommendation More studies and efforts are expected to establish a sustainable, captive colony of the Yangtze finless porpoise, which will
not only greatly expand our knowledge about the reproduction biology of this animal, but also help to redeem the wild population
through a careful yearly 'soft releasing' process. 相似文献
878.
畜禽养殖废水污染物浓度高、生物毒性大,导致传统生物处理工艺难以满足达标排放要求.为探究高效的畜禽养殖废水处理工艺,采用生物转盘作为主体工艺,利用异养硝化-好氧反硝化菌(简称"HN-AD菌")为生物强化菌剂,对比了强化污泥挂膜和菌剂挂膜两种不同生物强化方式下该工艺在启动时间、碳耗、能耗、真实废水处理效果及微生物多样性方面的差异,以确定最佳生物强化方式.结果表明:①模拟废水试验中,菌剂挂膜反应器启动时间(19 d)明显短于强化污泥挂膜(33 d),参数优化后发现,在相同处理效果下,前者碳耗、能耗较后者分别低48.22%、33.33%.②真实废水处理试验中,菌剂挂膜反应器的CODCr、NH4+-N、TN平均去除率较后者分别高7.11%、26.97%、29.14%.③在微生物多样性方面,菌剂挂膜体系中Comamonas(丛毛单胞菌属)相对丰度是强化污泥挂膜体系的10倍左右,推测Comamonas可能是在异养硝化好氧反硝化过程中发挥关键作用的菌属.④SEM观察发现菌剂挂膜生物转盘盘片上的生物膜更薄,但HN-AD优势菌富集程度更高.研究显示,菌剂挂膜反应器对模拟废水、真实废水的处理效果均优于强化污泥挂膜反应器,且效果更稳定. 相似文献
879.
针对国内目前尚未开展过民机整机级实验室降/扬雪试验、对适航关注的降/扬雪环境参数不明确等问题,分析了气候环境实验室降/扬雪环境表征方法。首先从与降/扬雪相关的气象标准、环境试验标准、适航符合性验证方法和国外民机相关试验资料这四个方面着手收集了与降/扬雪环境相关的文献,分析提炼出了10个可对降/扬雪环境进行表征的方法。然后以民机降/扬雪环境下的适航符合性验证要求为基础,结合上述提炼出的10个表征方法,分析确定采用温度、能见度、总含水量、风速和雪密度对气候环境实验室降/扬雪环境进行表征,研究得到的降/扬雪环境表征方法可为将来在气候环境实验室内开展民机降/扬雪试验提供参考。 相似文献
880.