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901.
902.
Estrogenic effects of water from the Yangtze River (Nanjing section) on goldfish (Carassius auratus) after an early life stage exposure 总被引:1,自引:0,他引:1
Effects of river water from the Yangtze River (Nanjing section) on fish development, vitellogenin (VTG) induction, gonado-somatic
index (GSI) and sex ratio were investigated by exposing goldfish (Carassius auratus) in the early life stage (from fertilization to 28 days
post-hatch) to water samples (25%, 50% and 100%) collected from three representative sections. The results showed that there was no
significant effect on hatching success for any of the exposure groups, but survival was significantly reduced when compared with the
control (P < 0.05). Body lengths, weights of all treated fish did not differ significantly from those of the control. Condition factors (CF)
of larval fish exposed to 50% and 100% river water from the Jiangxinzhou section and 100% river water from the Daqiao section were
significantly lower than that of the control (P< 0.05). VTG inductions were significant in larval fish exposed to all the dilution series
of river water. No significant difference in CF value was observed in any exposure group after 150 days of depuration. VTG was fully
eliminated after 75 days of depuration. For both female and male, GSI did not significantly differ between exposure groups and the
control after 150 days of convalescence. The highest female:male ratios were observed in response to the treatment with 50% or 100%
river water from the Jiangxinzhou section and 100% river water from the Daqiao section (53:47, 56:44 and 54:46, respectively), but no
significant difference in sex ratio was observed in any treated group when compared to the control. The results showed that early life
stage exposure of river water from the Yangtze River (Nanjing section) had adverse effects on goldfish development and reproductive
health, and the effects on CF and VTG were reversible after depuration in clean water. 相似文献
903.
The Royal Military College of Canada, located on the north eastern shore of Lake Ontario, possesses an abundance of copper roofs
and lacks surface water treatment prior to discharge into Lake Ontario. Rainwater, roof runoff and soil samples were collected and
analyzed for copper and other parameters. Copper was consistently detected in runoff samples with average concentrations of 3200 2100 g/L. Multivariable linear regression analysis for a dependant copper runoff concentration yielded an adjusted R2 value of 0.611,
based on an independent variable model using minimum temperature, maximum temperature, total precipitation, and wind speed. Lake
water samples taken in the vicinity of storm water outfalls draining areas with copper roofs ranged from 2.0 to 40 g/L copper. Such
data exceed the 2.0 g/L Canadian Water Quality Guidelines for the Protection of Aquatic Life as outlined by the Canadian Council of
Ministers of the Environment (CCME). Analysis of raw, filtered and digested forms suggested that the majority of copper present in
runoff and lake water samples was in a dissolved form. The majority of soils taken in this study displayed copper concentrations below
the 63 g/g CCME residential/parkland land use limits. These findings suggested that ion exchange processes between runoff water and
soil do not occur to a sufficient extent to elevate copper levels in soil. It may therefore be concluded that the eventual fate of copper,
which is not discharged via storm water outfalls, is lost to the water table and Lake Ontario through the sub-soil. 相似文献
904.
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909.
浅析啤酒全生命周期中的清洁生产机会 总被引:3,自引:0,他引:3
啤酒的全生命周期是指啤酒从原材料采购、储运,到啤酒生产过程的制麦、糖化、发酵、过滤、包装到生产出成品酒乃至到贮存、运输、进入市场的整个过程。本文从分析啤酒的全生命周期出发,找出周期中能耗高、物耗高、污染重的部位及环节,提出提高原材料和能源的利用率和产品质量、减少废弃物产生的技术经济环境可行的清洁生产方案,并简要分析方案实施的投资与效益,从而使啤酒生产企业达到“节能、降耗、减污、增效”的目的。 相似文献
910.
根据珠江三角洲地区16个典型站点2006年监测的PM10浓度数据,以珠江三角洲地区人群2006年PM10暴露浓度作为基准,采用泊松回归模型和寿命表方法,评价PM10浓度对人群健康影响.该区2006年PM10年均浓度达到73μg/m3,若所有监测城市PM10浓度达到国家二级标准(100μg/m3),成人(≥30岁)可避免死亡人数为2300人,人群平均期望寿命延长0.13a.当PM10年均浓度达到WHO推荐过渡指标值(70,50,30μg/m3)及指导值(20μg/m3)后,成人可避免死亡人数分别为8700,19700,32600,38500人;人群平均期望寿命分别延长0.47,1.1,1.9,2.3a. 相似文献