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101.
建立城市自然灾害承灾能力指标的思路探讨 总被引:10,自引:0,他引:10
本文论述了城市承灾能力的含义,分析了我国城市主要自然灾害以及承文体的类型和致灾因素,探讨了城市承灾能力指标,为城市承灾能力综合评判提供了依据. 相似文献
102.
第三届国际就地生物复原会议于1995年4月24至27日在美国加里福尼亚州圣迭哥市举行,会上交流的论文达700篇,涉及环境污染就地生物治理的各个方面。本文对会议有关情况作了简要介绍。 相似文献
103.
云南兰花生物技术的商品化开发 总被引:3,自引:1,他引:3
云南是我国兰科植物资源最丰富的地区,云南兰花共100属472种,中国传统的观赏兰花-兰属植物和具开发潜力的热带兰种类多、分布广,使云南成为天然的兰花资源基因 。近年来,采挖性的商品开发导致云南丰富的兰花资源遭到严重破坏。 相似文献
104.
Cao Junji Lee Shungcheng Zheng Xiangdong Ho Kinfai Zhang Xiaoye Guo Hai Chow Judith C. Wang Hongbin 《Water, Air, & Soil Pollution: Focus》2003,3(2):213-229
In April 1998, two intense dust storms were generated in CentralAsia and transported eastward across East Asia (15 and 19 April). This article presents the chemical characterization ofHong Kong (HK) aerosols during the dust storms. During the 15 Aprildust storm, hourly respiratory suspended particles (RSP)(particle diameter smaller than 10 m) concentrationsmonitored at 7 sites in Hong Kong reached the peak valuessynchronously between 9 and 11 a.m. on 17 April, in which thehighest concentration was 267 g m-3. Analysis ofthe RSP samples showed that concentrations of crustalelements (Ba, Ca, Cd, Cr, Fe, Mg, K+) and anthropogenicspecies (As, Ni, Pb, Zn, NH4
+, NO3
-,SO4
2- and total carbon) were substantiallyenhanced. Enhancement of these species was more than afactor of 2 to 14 relative to the non dust period. The totalcarbon content was high, at 59 g m-3 (notincluding carbonate), and the enrichment factors of Asand Pb on 17 April were 122 and 117, respectively. Thisimplied that anthropogenic materials together with mineraldust were transported to HK from Mainland China. Based onmaterial balance calculations, mineral dust contributed41% to the observed RSP mass on 17 April, which was 2 times thatof the nondust sample (22%). From the 5-day backwardtrajectory analysis, this storm was transported directlyfrom Northwest China to HK. However, there was nocorresponding observation for the 19 April dust stormaerosol. Consequently, 15 April storm had stronger impact onHK's atmosphere than 19 April storm. Compared to the HK AirQuality Objective, 15 April dust storm did not cause seriousair pollution in HK. 相似文献
105.
Zheng Lei Li Dewen Song Shuzheng Wang Hongtu Sui Jinjun 《Environment, Development and Sustainability》2022,24(3):3110-3125
Environment, Development and Sustainability - In order to reveal the distribution and migration law of downwind and upwind coal cutting, total dust (TD) and respirable dust (RD) concentration... 相似文献
106.
Impact of land use changes on water quality in headwaters of the Three Gorges Reservoir 总被引:1,自引:0,他引:1
Huicai Yang Guoqiang Wang Lijing Wang Binghui Zheng 《Environmental science and pollution research international》2016,23(12):11448-11460
The assessment of spatial and temporal variation of water quality influenced by land use is necessary to manage the environment sustainably in basin scales. Understanding the correlations between land use and different formats of nonpoint source nutrients pollutants is a priority in order to assess pollutants loading and predicting the impact on surface water quality. Forest, upland, paddy field, and pasture are the dominant land use in the study area, and their land use pattern status has direct connection with nonpoint source (NPS) pollutant loading. In this study, two land use scenarios (1995 and 2010) were used to evaluate the impact of land use changes on NPS pollutants loading in basins upstream of Three Gorges Reservoir (TGR), using a calibrated and validated version of the soil and water assessment tool (SWAT) model. The Pengxi River is one of the largest tributaries of the Yangtze River upstream of the TGR, and the study area included the basins of the Dong and Puli Rivers, two major tributaries of the Pengxi River. The results indicated that the calibrated SWAT model could successfully reproduce the loading of NPS pollutants in the basins of the Dong and Puli Rivers. During the 16-year study period, the land use changed markedly with obvious increase of water body and construction. Average distance was used to measure relative distribution patterns of land use types to basin outlets. Forest was mainly distributed in upstream areas whereas other land use types, in particular, water bodies and construction areas were mainly distributed in downstream areas. The precipitation showed a non-significant influence on NPS pollutants loading; to the contrary, interaction between precipitation and land use were significant sources of variation. The different types of land use change were sensitive to NPS pollutants as well as land use pattern. The influence of background value of soil nutrient on NPS pollutants loading was evaluated in upland and paddy field. It was found that total nitrogen (TN) and total phosphorous (TP) in upland were more sensitive to NPS pollutants loading than in paddy fields. The results of this study have implications for management of the TGR to reduce the loading of NPS pollutants into downstream water bodies. 相似文献
107.
108.
利用江苏台网15个地震台的84个地震DD-1短周期记录资料,通过m_(Lg)震级与持续时间τ和震中距Δ相关,得出该区持续时间震级M_D公式:M_D=a_0+0.44(lgτ)~2+0.00036Δ+DM这里,a_0为与记录分向和尾波截止水平有关的常数;DM为台站校正值。M_D标度内部单台标准差为0.09~0.10震级单位,M_D相对m_(Lg)的单台标准差为0.16~0.17震级单位。 相似文献
109.
2008年汶川8.0级地震发生以来,极震区泥石流爆发频率有增无减且规模越来越大,破坏性越来越强,严重威胁灾区人民生命财产安全。对比采取现场勘查、遥感图像分析、历史资料对比分析等方法,分析了极震区泥石流动力特征受地形、地层、物源等因素的影响,特别是泥石流爆发过程中深侵蚀和溃决对泥石流动力特征的影响。针对四川安县高川乡流域泥石流沟的调查和分析,建立泥石流流量-冲刷模型,分析了常规地区泥石流峰值流量与极震区泥石流峰值流量差别,推导出极震区峰值流量及冲刷深度定量计算公式。通过实例分析,理论与实际具有较好的一致性,对极震区泥石流动力参数计算具有较好适用性和有效性。 相似文献
110.