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以广东省某市为研究区域,通过研究其表层土壤重金属含量及空间分布特征,明确土壤重金属污染情况和优先控制因子,为该市土壤重金属污染防治提供基础数据.对该市221个土壤样品中的重金属含量特征进行分析,并通过潜在健康风险评估(HRA)模型、PMF受体模型和蒙特卡洛模型进行潜在健康风险评估、来源解析和主控因子分析.结果发现,该市土壤重金属ω(As)、ω(Hg)、ω(Cd)、ω(Pb)、ω(Cr)、ω(Cu)、ω(Ni)和ω(Zn)的平均值分别为18.16、0.43、1.46、68.57、98.34、64.19、26.53和257.32 mg·kg-1,变异程度为中高度变异.除Ni元素以外,土壤其余重金属元素含量均已一定程度超过广东省土壤背景值,且Cd和Zn的含量已超过国家二级标准,重金属污染已较为严重;重金属来源主要为工业源,自然母质、铅蓄电池制造、交通、人为耕作和农药化肥投入也对土壤重金属累积有不可忽视的影响;土壤重金属对儿童和成人均存在一定程度的可耐受致癌健康风险,非致癌风险可以忽略不计;儿童的潜在健康风险大于成人,主要暴露途径均为经口摄入;农药化肥投入源和As应该作为该市土壤重金属影响健康风险的主控因子,其次为混合源和Cr;重金属空间分布特征及相对污染程度存在差异,应深化分区监测管控,加强土壤的污染防治,减少土壤重金属的人为输入. 相似文献
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185.
Sen Liu Congren Yang Wei Liu Longsheng Yi Wenqing Qin 《Frontiers of Environmental Science & Engineering》2020,14(4):62
186.
复杂污染源下采煤沉陷区土壤重金属分布及行为特征 总被引:1,自引:0,他引:1
采用数理统计学、克里金插值等方法研究安徽淮北采煤沉陷区土壤中Cu、Zn、Cd、Cr、Ni、Pb、As和Hg等元素空间分布及其行为特征.结果表明:土壤中Zn平均值是农用地土壤污染风险筛选值的1.1倍,其他元素未超过筛选值.Cu富集在工业园区南部,Zn、As富集在两河交汇处、工业园区南部,Cd、Pb和Hg富集在沉陷区西部,Cr、Ni富集在沉陷区东部、西部;土壤剖面上Cu最大值出现在80 cm处,Ni最大值在40 cm处,其他元素最大值均在20 cm处.土壤中元素迁移程度为Cu最高,Zn、Cr、Hg和As最低;土壤中Cd活化率较高,达到27.1%,易被植物吸收富集. 相似文献
187.
González-Montaña JR Senís E Gutiérrez A Prieto F 《Environmental monitoring and assessment》2012,184(7):4029-4034
The levels of cadmium and lead in 36 raw bovine milk samples were analysed. These samples come from seven farms with a semi-extensive grazing system and were collected between the autumn of 2007 and the winter of 2008. All the farms were located in Asturias (Spain), a zone of great industrial and mining activity in the proximities of the Caudal River. The samples were collected in sterile precleaned polypropylene tubes and frozen until the analysis. After a lyophilization process, the samples were treated with nitric acid and microwave treatment. Cadmium and lead determinations were carried out using inductively coupled plasma mass spectrometry with sensibility under 0.2 ppb for liquid matrix. The lead content was found to vary from 0.71 to 16.06 μg/kg wet weight (w.w.), and the cadmium was lower than 2 μg/kg w.w. The levels of lead in milk are higher in those farms near zones of storage of mining waste depots, thermal power and areas with high levels of traffic. All the values found are in concordance with research carried out at non-polluted areas, and those for the lead are well below the European Union limitations. 相似文献
188.
Rasime Demirel Burhan Sen Duygu Kadaifciler Aysegul Yoltas Suzan Okten Evrim Ozkale Derya Berikten Robert A. Samson Alev Haliki Uztan Neriman Yilmaz Ozlem Abaci Gunyar Halide Aydogdu Ahmet Asan Merih Kivanc Soner Ozdil Erhan Sakartepe 《Environmental monitoring and assessment》2017,189(7):362
Pathogenic and/or opportunistic fungal species are major causes of nosocomial infections, especially in controlled environments where immunocompromised patients are hospitalized. Indoor fungal contamination in hospital air is associated with a wide range of adverse health effects. Regular determination of fungal spore counts in controlled hospital environments may help reduce the risk of fungal infections. Because infants have inchoate immune systems, they are given immunocompromised patient status. The aim of the present study was to evaluate culturable airborne fungi in the air of hospital newborn units in the Thrace, Marmara, Aegean, and Central Anatolia regions of Turkey. A total of 108 air samples were collected seasonally from newborn units in July 2012, October 2012, January 2013, and April 2013 by using an air sampler and dichloran 18% glycerol agar (DG18) as isolation media. We obtained 2593 fungal colonies comprising 370 fungal isolates representing 109 species of 28 genera, which were identified through multi-loci gene sequencing. Penicillium, Aspergillus, Cladosporium, Talaromyces, and Alternaria were the most abundant genera identified (35.14, 25.40, 17.57, 2.70, and 6.22% of the total, respectively). 相似文献
189.
糠醛渣纤维素酶解研究 总被引:1,自引:0,他引:1
以糠醛渣为原料进行纤维素酶解研究,考察了预处理方式、酶用量、底物浓度和酶解时间对糠醛渣酶解的影响,并将其与稀酸预处理的玉米芯进行对比.结果表明,未经处理的糠醛渣由于酸性较强并含有糠醛等抑制性的物质,不能直接用于酶解,水洗和Ca(OH)2脱毒法都可以显著提高糠醛渣的酶解效果;水洗糠醛渣的酶解最佳条件为:1∶9(g∶mL)的底物浓度、20 FPU/g(酶活/底物),酶解时间为48 h,在此条件下,还原糖浓度为35 g/L,糠醛渣的转化率为30%,糠醛渣中纤维素的转化率为61%. 相似文献
190.
Ying Hu Liu De Li Liu Min An Yin Lian Fu Ren Sen Zeng Shi Ming Luo Hanwen Wu Jim Pratley 《Ecological modelling》2009
Many plant species defend themselves against herbivorous insects indirectly by producing and releasing induced volatiles to attract natural enemies of the herbivores. In this paper, we consider the recruitment of natural enemies attracted by plant-induced volatiles and introduce the An–Liu–Johnson–Lovett model into the Lotka–Volterra model in an attempt to add this missing vital link in tritrophic interaction. Increase in attraction strength of plant-induced volatiles to the natural enemy leads to high fluctuation amplitude of plant biomass and herbivore population. When the attack strength of natural enemies reaches a certain level, fluctuation amplitude of plant biomass and herbivore population will decrease and plant biomass will approach to its environmental carrying capacity. The simulation demonstrates that plant volatile compounds induced by insects have led to the introduction of a third tritrophic level, e.g., natural enemies, into the plant–herbivore system, resulting in the coexistence of plants, insects, and natural enemies during the evolution process. 相似文献