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841.
京津冀地区空气质量跨区域补偿机制欠缺,已成为制约该区域大气污染联防联控的短板.基于投入产出模型,核算了2017年生产者负责原则与消费者负责原则下京津冀地区大气污染虚拟治理成本,分析了空气质量补偿主体及资金规模.结果发现,京津冀地区污染物排放具有较强的区域关联关系,说明治理大气污染不只要关注本地减排,还要加强不同地区间协同减排力度.天津市基于消费者负责原则下的虚拟治理成本最高,其次是石家庄市和唐山市.2017年,北京市应该提供空气质量补偿资金27.15亿元,用于补偿天津市和河北省其他城市大气污染治理损失,其中,石家庄市获得的补偿资金最高(10.99亿元),其次为天津市(3.24亿元).在当前减排成本从生产者向消费者传导机制不健全的背景下,亟需建立空气质量跨区域补偿机制及区域协调机构,统一负责空气质量补偿资金的缴纳及分配问题. 相似文献
842.
纳米塑料作为一种新兴污染物在水中可长久稳定存在,其表面吸附的重金属对水环境产生了潜在危害.本文研究了纳米塑料聚苯乙烯微球在吸附时间、溶液pH、氯化钠溶液、锰离子、温度等不同实验条件下对铅离子的吸附行为.结果表明,粒径为400 nm的单分散聚苯乙烯微球可快速吸附铅离子,吸附平衡时间约为30 min,吸附率达到53.30%.聚苯乙烯微球对铅离子的吸附动力学符合伪一级动力学,吸附等温线遵循Freundlich模型,吸附过程主要为非线性吸附.随着溶液pH的增加,铅离子平衡吸附量增加,静电作用是影响铅离子在聚苯乙烯微球上吸附的关键因素.增加溶液盐浓度,微塑料发生聚集,比表面积减小,吸附位点减少,铅离子的吸附量显著降低,在3.5%氯化钠溶液中,纳米塑料对铅离子的吸附率仅为7.5%.与重金属锰离子共存,可促进聚苯乙烯微球对铅离子的吸附.升高温度,纳米塑料对铅离子的平衡吸附量增加. 相似文献
843.
为实现氯酚(CPs)的高效降解和资源化利用,探究微生物燃料电池(MFC)体系优势功能菌,揭示生物降解路径.接种、驯化长春市南郊污水处理厂的厌氧活性污泥,获得生物膜阳极以构筑MFC-2,4,6-TCP体系,基于扫描电子电镜(SEM)、16S rRNA分析测序方法,考察生物膜阳极微生物的附着情况和优势菌种,基于电化学阻抗(EIS)、循环伏安(CV)和线性扫描伏安(LSV)等电化学分析手段,表征生物阳极的电化学性能和氧化还原能力.结果表明,生物膜阳极微生物种类丰富,其中Geobacter和Acinetobacter分别为MFC-2,4,6-TCP体系产电和降解驯化期的优势功能菌,体系最大输出电压可达0.55 V,最大功率密度为428.65 mW·m-2,对2,4,6-TCP的降解和矿化率可达97.5%和85.4%.随着MFC循环次数的增加,微生物代谢途径多样化,产电菌逐渐演替为协同菌,且优势功能菌对2,4,6-TCP降解的中间产物(环己醇),其毒性远低于氯酚或苯酚,更利于被微生物利用.该结果可为氯酚废水的实际处理提供新策略和技术参考. 相似文献
844.
以水源中央空调GHP1000为研究对象,通过确定功能单元、清单分析,提出了生命周期分析方法学模型,并对实际工作中发现的若干问题进行了讨论。 相似文献
845.
大亚湾惠州岸段城市化发展与海岸带生态系统保护协调研究 总被引:1,自引:0,他引:1
在分析海岸带生态系统结构、功能特点的基础上,指出大亚湾惠州岸段可持续发展的途径就是实现经济开发与海岸带生态环境保护之间的协调发展,为此,提出了区域生态--经济系统综合效益表达工,并运用该表达式,从大亚湾海水环境保护的角度出发,得出了惠州大亚湾沿岸地区在1994年-2010年间工业发展的合理速度。 相似文献
846.
beta-Carboline-3-carboxylic acid methylamide (FG 7142), an anxiogenic agent, has been detected in human urine. The urinary excretion level of FG 7142 in non-smokers was found to be 0.503 +/- 0.25 ng per day (mean +/- S.D., n=10), while that in smokers was found to be 2.418 +/- 0.384 ng per day (n=10). This suggests that humans are exposed to FG 7142 and that smokers are exposed to higher levels of FG 7142 than non-smokers. Considering the previous findings that FG 7142 is present in cigarette smoke, indoor and outdoor air and smoke condensate of tree leaves, humans may be exposed to FG 7142 via the airways and lungs, although we cannot exclude the possibility of exposure via foodstuffs. Results of animal experiments suggest that FG 7142 which enters the bloodstream is excreted into the urine via the kidneys within 24 h in an unchanged form. Therefore, monitoring the level of FG 7142 in urine may be useful for monitoring the exposure level of FG 7142. 相似文献
847.
848.
849.
Xiaodong Zou Zhemin Shen Tao Yuan Shan Yin Jingping Cai Liping Chen Wenhua Wang 《Atmospheric environment (Oxford, England : 1994)》2006,40(40):8068-8073
In this paper, a shifted power-law model, based on the wind profile model, had been supposed to simulate concentration gradient of nitrogen dioxide (NO2) with distance from a highway. Field experiments were performed for NO2 gradients from a highway in Shanghai by using passive samplers. The shifted power-law model was fitted well with experimental results of field experiments both in this study and in the literature. The results not only verified the validity of shifted power-law relationship between NO2 concentration and the distance from a highway, but also partially demonstrated that there were some significant similarities between wind profile and air pollutants concentration profile near highway. With known concentration of chosen reference point and appropriate value of the parameter k, the model could be practically applied for predicting the NO2 distributions near a highway. The methods of determining the parameter k were also discussed for further detailed studies. 相似文献
850.
Preparation of sulfurized powdered activated carbon from waste tires using an innovative compositive impregnation process 总被引:1,自引:0,他引:1
Yuan CS Lin HY Wu CH Liu MH Hung CH 《Journal of the Air & Waste Management Association (1995)》2004,54(7):862-870
The objective of this study is to develop an innovative compositive impregnation process for preparing sulfurized powdered activated carbon (PAC) from waste tires. An experimental apparatus, including a pyrolysis and activation system and a sulfur (S) impregnation system, was designed and applied to produce sulfurized PAC with a high specific surface area. Experimental tests involved the pyrolysis, activation, and sulfurization of waste tires. Waste-tire-derived PAC (WPAC) was initially produced in the pyrolysis and activation system. Experimental results indicated that the Brunauer-Emmett-Teller (BET) surface area of WPAC increased, and the average pore radius of WPAC decreased, as water feed rate and activation time increased. In this study, a conventional direct impregnation process was used to prepare the sulfurized PAC by impregnating WPAC with sodium sulfide (Na2S) solution. Furthermore, an innovative compositive impregnation process was developed and then compared with the conventional direct impregnation process. Experimental results showed that the compositive impregnation process produced the sulfurized WPAC with high BET surface area and a high S content. A maximum BET surface area of 886 m2/g and the S content of 2.61% by mass were obtained at 900 degrees C and at the S feed ratio of 2160 mg Na2S/g C. However, the direct impregnation process led to a BET surface area of sulfurized WPAC that decreased significantly as the S content increased. 相似文献