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311.
NKA—Ⅱ大孔吸附树脂吸附高浓度苯胺溶液的试验研究 总被引:4,自引:0,他引:4
本文利用NKA-Ⅱ大孔吸附树脂对高浓度苯胺溶液进行了静态吸附试验,希望利用大孔吸附树脂从化工废水中回收苯胺。 相似文献
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Climate warming can substantially impact embryonic development and juvenile growth in oviparous species. Estimating the overall impacts of climate warming on oviparous reproduction is difficult because egg-laying events happen throughout the reproductive season. Successful egg laying requires the completion of embryonic development as well as hatching timing conducive to offspring survival and energy accumulation. We propose a new metric—egg-laying opportunity (EO)—to estimate the annual hours during which a clutch of freshly laid eggs yields surviving offspring that store sufficient energy for overwintering. We estimated the EO within the distribution of a model species, Sceloporus undulatus, under recent climate condition and a climate-warming scenario by combining microclimate data, developmental functions, and biophysical models. We predicted that EO will decline as the climate warms at 74.8% of 11,407 sites. Decreasing hatching success and offspring energy accounted for more lost EO hours (72.6% and 72.9%) than the occurrence of offspring heat stress (59.9%). Nesting deeper (at a depth of 12 cm) may be a more effective behavioral adjustment for retaining EO than using shadier (50% shade) nests because the former fully mitigated the decline of EO under the considered warming scenario at more sites (66.1%) than the latter (28.3%). We advocate for the use of EO in predicting the impacts of climate warming on oviparous animals because it encapsulates the integrative impacts of climate warming on all stages of reproductive life history. 相似文献
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Release Characteristics of Nutrients from Polymer-coated Compound Controlled Release Fertilizers 总被引:2,自引:0,他引:2
Reliable information regarding release characteristics of nutrients from a polymer-coated controlled release fertilizer (CRF) is essential for beneficial agronomic and environmental results. Significant knowledge regarding nitrogen release from polymer-coated urea was gained while the information regarding the release of the different nutrients contained in polymer-coated compound N–P–K CRF remains limited. An experiment in which major factors affecting the differential release of nutrients from two coated compound CRF was performed in free water, water saturated sand and sand at field capacity. In general, nitrate release was the fastest, followed by ammonium and potassium whereas phosphate was significantly slower, with a rate of linear release in free water 45–70% slower than that of nitrate. Little differences were obtained for the lag periods of nitrate, ammonium and potassium release (2–10 days) under the experimental conditions, whereas for P they were one order of magnitude larger. The main factor slowing the release was assumed to be the lower solubility of ions with P being the least soluble. Release into free water was, expectedly, somewhat faster than that into saturated sand and significantly faster as compared to sand at field capacity and particularly so for P. Raising the temperature from 20 °C to 40 °C increased the rate of linear release of the different nutrients. The energy of activation, EArel, estimated for the linear release, of the different nutrients, was narrow ranging between 37 to 46 (KJ mol−1) whereas the mean values obtained for the two CRF, differing by 50% in coating thickness, was non-significant. However, EArel was significantly different in different media. The complex effect of temperature on the lag period and nutrient interactions during release deserve further investigation. 相似文献
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九寨沟风景区游客入游距离特征研究 总被引:16,自引:2,他引:16
九寨沟风景区属于长江支流水系的上游,是长江支流源头区以景观资源(尤其是水景观)及生态旅游资源为特色的典型地区,目前旅游业成为当地及同类地区的旅游重要产业。旅游市场是当地旅游发展基础之一。在实地游客抽样调查及旅游区游客登记统计共涉及约2万人统计资料及数据库处理的基础上较系统地研究了九寨沟入游游客的入游距离特征。对九寨沟不同目标市场游客的入游距离特征进行了统计描述,揭示了游客入游距离与年龄、收入、职业、文化、心理收入、旅游态度相关,而与旅游动机相关性不明显,景观偏好可以反映游客的旅游心理特征,并在一定程度上影响入游距离。同时揭示了入游距离感知的距离衰减特征,印证了心理学感知理论中的韦伯理论在距离感知中的体现。还解释了游客的主观假设替代旅游地的旅游距离与入游距离呈线性相关关系。 相似文献
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气候变化与城市发展对城市气象灾害的影响及对策——以西安市为例 总被引:2,自引:0,他引:2
利用西安市1951-2006年气温、降水、风以及天气现象等气象观测资料,分析了在全球变暖及城市发展背景下,西安市城市干旱、城市内涝、高温热浪、大风、冰雪天气、雷电灾害等主要城市气象灾害特征及影响.随着城市建设的快速发展以及气候变化的加剧,水资源供需不平衡造成的城市干旱仍是西安可持续发展面临的重要问题;20世纪90年代以来,在降水呈现减少趋势下,极端强降水发生的频率增加,城市内涝严重;高温热浪、雷电灾害、大风、降雪冰冻天气等城市气象灾害对城市的正常运转的影响也日益突出.针对城市气象灾害的影响,从气象防灾减灾体系建设方面提出了城市气象灾害的防御对策. 相似文献