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461.
Fertility of lateral spikelets determines the two-rowed or six-rowed spikes of barley (Hordeum vulgare L.), which results in significantly different grain yields. The change in row type from two-rowed to six-rowed shows remarkable domestication characteristics. The Qinghai-Tibet plateau has abundant resources of wild and cultivated barley, and is considered one of the centers of domestication and genetic diversity of cultivated barley. In order to obtain a primary understanding of the genetic basis of lateral spike development regulation and the domestication process in cultivated Tibetan barley, an F2 segregation population was constructed by crossing the two-rowed wild barley accession ZYM0083 with the six-rowed landraces Linzhiheiliuleng. Genetic analysis showed that the row type was controlled by a single gene. Using the specific-locus amplified fragment sequencing (SLAF-seq) technology and bulked segregant analysis (BSA), two DNA pools from 22 two-rowed spike individuals and 22 six-rowed spike individuals of the F2 population were constructed and sequenced. A total of 456 691 SLAF tags were obtained. By adopting the ED and SNP index for association analysis, three candidate regions with a 53.84-Mb interval and containing 536 genes were obtained. Four-hundred thirteen, 189, and 160 annotated genes were acquired by GO, KEGG, and COG libraries, respectively. Loci that control lateral spike development in Tibetan barley were primarily mapped by SLAF-seq, and the results presented in this study will facilitate the fine mapping and cloning of target genes. © 2018 Science Press. All rights reserved. 相似文献
462.
纳米金属氧化物对土壤酶活性的影响研究进展 总被引:1,自引:0,他引:1
纳米金属氧化物的大量生产和广泛应用使其不可避免地进入环境中,土壤是其释放到环境中主要的汇。纳米颗粒由于尺寸效应,具有许多独特的物理化学性质,其进入环境后潜在的生态和健康风险问题日益受到研究者的关注。土壤酶是土壤生物化学过程的主要参与者,也是生态系统物质循环和能量流动过程中最活跃的生物活性物质。土壤酶活性的变化能反映土壤中生化反应的情况,可作为评价土壤中纳米材料污染状况的生物学指标。本文较系统地回顾和总结了纳米金属氧化物对土壤酶活性的影响及可能的影响途径,探讨了纳米金属氧化物作用于土壤酶的主要影响途径,并展望了未来研究主要发展方向。 相似文献
463.
化学品的快速生物降解性直接影响其在环境中的迁移、转化和归宿,是鉴别其环境危害性和持久性的基本指标,是政府管理部门对化学品进行风险管理的重要科学依据,在生态毒理测试中具有非常重要的地位。为探讨试验方法、接种物来源以及两者的交互效应对苯甲酸钠生物降解率的影响,2013—2015年间以广州地区2个主要处理生活污水的污水处理厂(DTS、LD)为接种物来源,采用OECD 301系列试验方法(301B、301D和301F)进行了苯甲酸钠的快速生物降解性试验,共获得89个标准化测试数据。统计分析结果显示,接种物来源、试验方法与接种物来源的交互效应对苯甲酸钠生物降解率影响不显著,但试验方法单一因素的影响显著。本研究表明,当受试物为易生物降解时,接种物来源、试验方法和接种物来源的交互效应对该受试物的生物降解率无显著的影响,但在同一条件下,选择不同的试验方法往往会导致最终生物降解率出现明显差异。 相似文献
464.
Huang Huang Jie Wu Jian Ye Tingjin Ye Jia Deng Yongmei Liang Wei Liu 《Frontiers of Environmental Science & Engineering》2018,12(6):7
Pharmaceutically active compounds in wastewater released from human consumption have received considerable attention because of their possible risks for aquatic environments. In this study, the occurrence and removal of 10 pharmaceuticals in three municipal wastewater treatment plants in southern China were investigated and the environmental risks they posed were assessed. Nifedipine, atenolol, metoprolol, valsartan and pravastatin were detected in the influent wastewater. The highest average concentration in the influents was observed for metoprolol (164.6 ng/L), followed by valsartan (120.3 ng/L) in August, while median concentrations were higher in November than in August. The total average daily mass loadings of the pharmaceuticals in the three plants were 289.52 mg/d/person, 430.46 mg/d/person and 368.67 mg/d/person, respectively. Elimination in the treatment plants studied was incomplete, with metoprolol levels increasing during biological treatment. Biological treatment was the most effective step for PhACs removal in all of the plants studied. Moreover, the removal of PhACs was observed with higher efficiencies in August than in November. The WWTP equipped with an Unitank process exhibited similar removals of most PhACs as other WWTPs equipped with an anoxic/oxic (A/O) process or various anaerobic-anoxic-oxic (A2/O) process. The environmental risk assessment concluded that all of the single PhAC in the effluents displayed a low risk (RQ<0.1) to the aquatic environments. 相似文献
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466.
Phyllosphere is an important reservoir of antibiotic resistance genes(ARGs), but the transfer mechanism of ARGs from soil and air to phyllosphere remains unclear. This study demonstrated that soil-air-phyllosphere was the dominant ARG transfer pathway, and blocking it by film mulching can reduce typical phyllosphere ARGs in lettuce by 80.7%-98.7%(89.5% on average). To further eliminate phyllosphere ARGs in lettuce grown with film mulching, the internal soil-endosphere-phyllosphere transfer pathw... 相似文献
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468.
饮用水中磷与细菌再生长的关系 总被引:3,自引:0,他引:3
采用改进的可同化有机碳(AOC)和微生物可利用磷(MAP)方法,针对T市J水厂水源水、处理工艺以及一条配水干管中磷对细菌生长的限制作用进行了研究.结果表明:①水源水与处理工艺中MAP较高(5~38μg/L),配水管网中MAP较低(<5μg/L),且管网水中的MAP随着管线的延长基本保持不变.②常规处理工艺能够有效地去除水中的MAP(去除率为34.0%~83.7%).③在水源水和处理工艺中,水样的AOCpotential<、sub>、AOCP与AOCnative没有显著差别,说明AOC是微生物生长繁殖的决定因素.该研究配水干管中,水样的AOCpotential、AOCP为AOCnative的2~8.7倍,磷成为细菌再生长的限制因子. 相似文献
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