全文获取类型
收费全文 | 581篇 |
免费 | 34篇 |
国内免费 | 226篇 |
专业分类
安全科学 | 48篇 |
废物处理 | 41篇 |
环保管理 | 58篇 |
综合类 | 307篇 |
基础理论 | 89篇 |
污染及防治 | 220篇 |
评价与监测 | 28篇 |
社会与环境 | 17篇 |
灾害及防治 | 33篇 |
出版年
2024年 | 1篇 |
2023年 | 7篇 |
2022年 | 23篇 |
2021年 | 25篇 |
2020年 | 21篇 |
2019年 | 18篇 |
2018年 | 19篇 |
2017年 | 21篇 |
2016年 | 24篇 |
2015年 | 29篇 |
2014年 | 49篇 |
2013年 | 67篇 |
2012年 | 53篇 |
2011年 | 45篇 |
2010年 | 42篇 |
2009年 | 51篇 |
2008年 | 35篇 |
2007年 | 40篇 |
2006年 | 37篇 |
2005年 | 31篇 |
2004年 | 15篇 |
2003年 | 18篇 |
2002年 | 19篇 |
2001年 | 25篇 |
2000年 | 16篇 |
1999年 | 18篇 |
1998年 | 10篇 |
1997年 | 16篇 |
1996年 | 18篇 |
1995年 | 10篇 |
1994年 | 8篇 |
1993年 | 9篇 |
1992年 | 4篇 |
1991年 | 2篇 |
1990年 | 11篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1987年 | 1篇 |
排序方式: 共有841条查询结果,搜索用时 125 毫秒
231.
Cadmium-induced DNA damage and mutations in Arabidopsis plantlet shoots identified by DNA fingerprinting 总被引:1,自引:0,他引:1
Random amplified polymorphic DNA (RAPD) test is a feasible method to evaluate the toxicity of environmental pollutants on vegetal organisms. Herein, Arabidopsis thaliana (Arabidopsis) plantlets following Cadmium (Cd) treatment for 26 d were screened for DNA genetic alterations by DNA fingerprinting. Four primers amplified 20-23 mutated RAPD fragments in 0.125-3.0 mg L−1 Cd-treated Arabidopsis plantlets, respectively. Cloning and sequencing analysis of eight randomly selected mutated fragments revealed 99-100% homology with the genes of VARICOSE-Related, SLEEPY1 F-box, 40S ribosomal protein S3, phosphoglucomutase, and noncoding regions in Arabidopsis genome correspondingly. The results show the ability of RAPD analysis to detect significant genetic alterations in Cd-exposed seedlings. Although the exact functional importance of the other mutated bands is unknown, the presence of mutated loci in Cd-treated seedlings, prior to the onset of significant physiological effects, suggests that these altered loci are the early events in Cd-treated Arabidopsis seedlings and would greatly improve environmental risk assessment. 相似文献
232.
233.
234.
235.
Sixteen USEPA priority polycyclic aromatic hydrocarbons (PAHs) extracted by Soxhlet extraction (S-PAHs) with dichloromethane and routine accelerated solvent extraction (A-PAHs) with 1:1 toluene/methanol, respectively, were investigated in 24 soil samples from two cities in the center of the Pearl River Delta, South China. Polycyclic aromatic hydrocarbons, methylphenanthrene and perylene, in two soils, two sediments, and an immature oil shale were also sequentially extracted by accelerated solvent extraction (ASE) with each of four different organic solvents for three times. The A-PAHs' concentrations are 2.41 times the S-PAHs' concentrations. For sequential three ASEs, PAHs in the first extract account for 56 to 67% of their total concentrations in the sequential three extractions and toluene displays the best extraction performance among the four solvents. Diagnostic ratios of PAHs in Soxhlet extraction, routine ASE, and sequential ASE with each solvent for a given sample are very similar, suggesting their identical petrogenic and pyrogenic sources in the soils and sediments. But the PAH ratios for the shale have an obvious petrogenic origin. The perylene/5-ring PAH ratios indicate a diagenetic source, especially in the shale and sediments. The correlation analysis shows that A-PAHs/S-PAHs is better associated with the contents of total organic carbon (TOC) than those of black carbon (BC). The above results indicate the significant petrogenic origin of PAHs and the important effect of organic matter on their extraction and distribution in the investigated field soils/sediments. 相似文献
236.
等离子气化技术在固体废物处理中的应用 总被引:3,自引:0,他引:3
针对国内固体废物处理的经验和情况,从保证处理的无害化效果以及让固体废物的处理经济可行结合的角度,介绍了等离子气化技术的应用效果及优势,认为采用等离子气化技术进行固体废物处理的时机已经成熟。 相似文献
237.
火电厂烟气在线监测系统存在的主要问题及进一步加强在线监测工作的建议 总被引:1,自引:0,他引:1
火电厂燃煤过程排放的污染物是我国大气污染的主要来源之一,烟气排放连续监测系统(CEMS)是实现烟气排放连续监测有效的现代化仪器设备。介绍了目前我国火电厂烟气的CEMS主要存在的问题,并针对这些存在的问题提出了相应的解决方案。 相似文献
238.
Gavin Gong Lucien Wang Laura Condon Alastair Shearman Upmanu Lall 《Journal of the American Water Resources Association》2010,46(3):574-585
Gong, Gavin, Lucien Wang, Laura Condon, Alastair Shearman, and Upmanu Lall, 2010. A Simple Framework for Incorporating Seasonal Streamflow Forecasts Into Existing Water Resource Management Practices. Journal of the American Water Resources Association (JAWRA) 46(3):574-585. DOI: 10.1111/j.1752-1688.2010.00435.x Abstract: Climate-based streamflow forecasting, coupled with an adaptive reservoir operation policy, can potentially improve decisions by water suppliers and watershed stakeholders. However, water suppliers are often wary of straying too far from their current management practices, and prefer forecasts that can be incorporated into existing system modeling tools. This paper presents a simple framework for utilizing streamflow forecasts that works within an existing management structure. Climate predictors are used to develop seasonal inflow forecasts. These are used to specify operating rules that connect to the probability of future (end of season) reservoir states, rather than to the current storage, as is done now. By considering both current storage and anticipated inflow, the likelihood of meeting management goals can be improved. The upper Delaware River Basin in the northeastern United States is used to demonstrate the basic idea. Physically plausible climate-based forecasts of March-April reservoir inflow are developed. Existing simulation tools and rule curves for the system are used to convert the inflow forecasts to reservoir level forecasts. Operating policies are revised during the forecast period to release less water during forecasts of low reservoir level. Hindcast simulations demonstrate reductions of 1.6% in the number of drought emergency days, which is a key performance measure. Forecasts with different levels of skill are examined to explore their utility. 相似文献
239.
240.
Thermochemical esterifying citric acid onto lignocellulose for enhancing methylene blue sorption capacity of rice straw 总被引:1,自引:0,他引:1
In this paper, rice straw was esterified thermochemically with citric acid (CA) to produce potentially biodegradable cationic sorbent. The modified rice straw (MRS) and crude rice straw (CRS) were evaluated for their methylene blue (MB) removal capacity from aqueous solution. The effects of various experimental parameters (e.g., initial pH, sorbent dose, dye concentration, ion strength, and contact time) were examined. The ratio of MB sorbed on CRS increased as the initial pH was increased from pH 2 to 10. For MRS, the MB removal ratio came up to the maximum value beyond pH 3. The 1.5g/l or up of MRS could almost completely remove the dye from 250mg/l of MB solution. The ratio of MB sorbed kept above 98% over a range from 50 to 450mg/l of MB concentration when 2.0g/l of MRS was used. Increase in ion strength of solution induced decline of MB sorption. The isothermal data fitted the Langmuir model. The sorption processes followed the pseudo-first-order rate kinetics. The intraparticle diffusion rate constant (k(id)) was greatly increased due to modification. 相似文献