全文获取类型
收费全文 | 7089篇 |
免费 | 59篇 |
国内免费 | 41篇 |
专业分类
安全科学 | 161篇 |
废物处理 | 288篇 |
环保管理 | 689篇 |
综合类 | 1042篇 |
基础理论 | 1458篇 |
环境理论 | 3篇 |
污染及防治 | 1765篇 |
评价与监测 | 562篇 |
社会与环境 | 1187篇 |
灾害及防治 | 34篇 |
出版年
2022年 | 73篇 |
2021年 | 93篇 |
2020年 | 44篇 |
2019年 | 68篇 |
2018年 | 132篇 |
2017年 | 152篇 |
2016年 | 183篇 |
2015年 | 124篇 |
2014年 | 234篇 |
2013年 | 604篇 |
2012年 | 260篇 |
2011年 | 316篇 |
2010年 | 252篇 |
2009年 | 287篇 |
2008年 | 342篇 |
2007年 | 385篇 |
2006年 | 305篇 |
2005年 | 276篇 |
2004年 | 264篇 |
2003年 | 239篇 |
2002年 | 229篇 |
2001年 | 257篇 |
2000年 | 207篇 |
1999年 | 101篇 |
1998年 | 73篇 |
1997年 | 79篇 |
1996年 | 63篇 |
1995年 | 84篇 |
1994年 | 76篇 |
1993年 | 59篇 |
1992年 | 62篇 |
1991年 | 64篇 |
1990年 | 76篇 |
1989年 | 58篇 |
1988年 | 51篇 |
1987年 | 43篇 |
1986年 | 49篇 |
1985年 | 50篇 |
1984年 | 52篇 |
1983年 | 38篇 |
1982年 | 52篇 |
1981年 | 39篇 |
1980年 | 46篇 |
1979年 | 45篇 |
1977年 | 35篇 |
1975年 | 31篇 |
1973年 | 34篇 |
1972年 | 41篇 |
1971年 | 31篇 |
1969年 | 32篇 |
排序方式: 共有7189条查询结果,搜索用时 203 毫秒
861.
Jun Liao Malini Sathanoori Svetlana A. Yatsenko Jie Hu Sally J. Kochmar Lori Hoffner W. Allen Hogge Urvashi Surti 《黑龙江环境通报》2012,32(12):1166-1169
862.
863.
J.M. Hoff P.V. Borgoul G. Tuncel J.M. Ondov W.R. Kelly L.T. Chen 《Journal of the Air & Waste Management Association (1995)》2013,63(8):721-728
ABSTRACT A stable rare-earth isotopic tracer was used to measure the deposition of KNO3 particles on soybean leaves by direct measurement of the tracer on the plant surfaces by thermal-ionization mass spectrometry. Submicrometer particles, made from a solution containing 3 |mg mL-1 neodymium isotope (148Nd, 87.9%) and 1,000 mg mL-1 KNO3, were dispersed with a two-fluid nozzle and released upwind of a soybean field. Total suspended- and size-fractionated-aerosol particles were collected on an open-face filter and in a micro-orifice impactor, respectively, at a distance of 40 m from the release point. Soybean leaves exposed to the plume were collected at distances ranging from 25 to 100 m. As little as 5.5 pg of the tracer (i.e., excess 148Nd) was detected in soybean leaves at signal-to-noise ratios ranging from 7,500 to 240,000, in the presence of 200 to 2,700 pg of naturally occurring Nd. The dry-particle deposition velocity, determined from the ratio of the aerial concentration and directly deposited aerosol (geometric mass mean diameter, 0.20 mm) flux, and its corresponding analytical uncertainty were 0.30 cm sec-1 and 2.5%, respectively. 相似文献
864.
865.
866.
Lisa G. Shaffer Justine Coppinger S. Annie Morton Sarah Alliman Jessica Burleson Ryan Traylor Cathryn Walker Steve Byerly Allen N. Lamb Roger Schultz J. Britt Ravnan Catherine D. Kashork Beth S. Torchia Scott Sulpizio Kyle Sundin Mack Schermer Karl Adler Stephanie Dallaire Blake C. Ballif 《黑龙江环境通报》2011,31(8):778-787
867.
Non-invasive prenatal screening (NIPS) has revolutionized the approach to prenatal fetal aneuploidy screening. Many commercial providers now offer analyses for sub-chromosomal copy number variations (CNVs). Here, we review the use of NIPS in the context of screening for microdeletions and microduplications, issues surrounding the choice of disorders tested for, and the advantages and disadvantages associated with the inclusion of microdeletions to current NIPS. Several studies have claimed benefits; however, we suggest that microdeletions have not demonstrated a low enough false positive rate to be deemed practical or ethically acceptable, especially considering their low positive predictive values. Because a positive NIPS result should be confirmed using diagnostic techniques, and false positive rates are as high as 90% for some microdeletions, diagnostic testing seems preferable when the goal is to maximize the detection of microdeletion or microduplication syndromes. 相似文献
868.
J. García-Ten E. Monfort M.P. Gómez-Tena V. Sanz 《Journal of Cleaner Production》2011,19(9-10):1110-1116
The manufacture of traditional ceramic products (ceramic tiles, roof tiles, and bricks) is often associated with the emission of F, Cl, and S compounds during the firing stage. According to the literature, fluorine emissions can be reduced by adding CaCO3 to the raw materials mixture used in fabricating these products. However, data available to the authors indicate that this procedure, which has been successfully applied in manufacturing structural ceramics (roof tiles and bricks), is ineffective in ceramic tile manufacture and modifies tile end properties.This paper examines the possibility of reducing such emissions by applying coatings of alkaline-earth carbonates on to the ceramic tile bottom surface to retain the acid compounds emitted during tile firing. The effectiveness of MgCO3, CaCO3, SrCO3, and BaCO3 coatings for retaining these acid emissions was studied, using the evolved gas analysis (EGA) technique with a TG-DSC-FTIR-QM instrument.The SrCO3 coating was found to provide the greatest retention, showing that SO2 and HCl were retained more efficiently than HF. The presence of fluorides, chlorides, and sulphates of Ca, Sr, and Ba was verified in the respective fired coatings, confirming the existence of chemical reactions between the emitted acid compounds and the coating materials at high temperature. 相似文献
869.
J. Besseau-Ayasse C. Violle-Poirsier A. Bazin N. Gruchy A. Moncla F. Girard M. Till F. Mugneret A. Coussement F. Pelluard M. Jimenez P. Vago M. F. Portnoï C. Dupont C. Beneteau F. Amblard M. Valduga J. L. Bresson F. Carré-Pigeon N. Le Meur S. Tapia C. Yardin A. Receveur J. Lespinasse E. Pipiras M. P. Beaujard P. Teboul S. Brisset M. Catty E. Nowak N. Douet Guilbert H. Lallaoui S. Bouquillon V. Gatinois G. Joly-Helas F. Prieur F. Cartault D. Martin P. Kleinfinger D. Molina Gomes M. Doco-Fenzy F. Vialard 《黑龙江环境通报》2014,34(5):424-430
870.
Kovacevic R. Teodorovic I. Kaisarevic S. Planojevic I. Fa S. Dakic V. Pogrmic K. Virijevic S. 《Environmental science and pollution research international》2009,16(1):130-131
Environmental Science and Pollution Research - 相似文献