全文获取类型
收费全文 | 143篇 |
免费 | 10篇 |
国内免费 | 47篇 |
专业分类
安全科学 | 11篇 |
废物处理 | 10篇 |
环保管理 | 18篇 |
综合类 | 70篇 |
基础理论 | 27篇 |
污染及防治 | 39篇 |
评价与监测 | 9篇 |
社会与环境 | 7篇 |
灾害及防治 | 9篇 |
出版年
2023年 | 3篇 |
2022年 | 3篇 |
2021年 | 7篇 |
2020年 | 3篇 |
2019年 | 5篇 |
2018年 | 6篇 |
2017年 | 10篇 |
2016年 | 8篇 |
2015年 | 6篇 |
2014年 | 13篇 |
2013年 | 9篇 |
2012年 | 11篇 |
2011年 | 17篇 |
2010年 | 9篇 |
2009年 | 8篇 |
2008年 | 7篇 |
2007年 | 9篇 |
2006年 | 8篇 |
2005年 | 3篇 |
2004年 | 8篇 |
2003年 | 9篇 |
2002年 | 4篇 |
2001年 | 7篇 |
2000年 | 1篇 |
1999年 | 3篇 |
1998年 | 1篇 |
1997年 | 6篇 |
1996年 | 8篇 |
1995年 | 4篇 |
1993年 | 1篇 |
1991年 | 2篇 |
1987年 | 1篇 |
排序方式: 共有200条查询结果,搜索用时 156 毫秒
171.
Renjun Zhou Shenzheng Zeng Dongwei Hou Jian Liu Shaoping Weng Jianguo He Zhijian Huang 《环境科学学报(英文版)》2019,31(6):248-256
Antibiotic resistance genes(ARGs), human pathogenic bacteria(HPB), and HPB carrying ARGs are public issues that pose a high risk to aquatic environments and public health. Their diversity and abundance in water, intestine, and sediments of shrimp culture pond were investigated using metagenomic approach. A total of 19 classes of ARGs, 52 HPB species, and 7 species of HPB carrying ARGs were found. Additionally, 157, 104, and 86 subtypes of ARGs were detected in shrimp intestine, pond water, and sediment samples, respectively. In all the samples, multidrug resistance genes were the highest abundant class of ARGs. The dominant HPB was Enterococcus faecalis in shrimp intestine, Vibrio parahaemolyticus in sediments, and Mycobacterium yongonense in water, respectively. Moreover, E. faecalis(contig Intestine_364647)and Enterococcus faecium(contig Intestine_80272) carrying efr A, efr B and ANT(6)-Ia were found in shrimp intestine, Desulfosaricina cetonica(contig Sediment_825143) and Escherichia coli(contig Sediment_188430) carrying mex B and APH(3′)-IIa were found in sediments, and Laribacter hongkongensis(contig Water_478168 and Water_369477), Shigella sonnei(contig Water_880246),and Acinetobacter baumannii(contig Water_525520) carrying sul1, sul2, ere A, qac H, OXA-21, and mph D were found in pond water. Mobile genetic elements(MGEs) analysis indicated that horizontal gene transfer(HGT) of integrons, insertion sequences, and plasmids existed in shrimp intestine, sediment, and water samples, and the abundance of integrons was higher than that of other two MGEs. The results suggested that HPB carrying ARGs potentially existed in aquatic environments, and that these contributed to the environment and public health risk evaluation. 相似文献
172.
173.
新一代分子标记技术——AFLP 总被引:31,自引:0,他引:31
AFLP(Amplifiedfragmentlengthpolymorphism)是近年来发展起来的最有效的新一代分子标记技术.本文对AFLP的发生发展、基本原理、反应程序,在植物分子生物学研究中的应用以及方法本身的优缺点进行了介绍和评述. 相似文献
174.
Kevin C. Weng Andre M. Boustany Peter Pyle Scot D. Anderson Adam Brown Barbara A. Block 《Marine Biology》2007,152(4):877-894
Satellite telemetry studies of 20 adult and sub-adult white sharks (360–530 cm estimated total length (TL)) in the eastern
North Pacific during 1999–2005 revealed long distance seasonal migrations from the coast of California to an offshore focal
area 2,500 km west of the Baja Peninsula, as well as the Hawaii Islands. Three tags were recovered allowing detailed behavioral
analyses, including one shark’s migration cycle from the coast to the offshore focal area and back. While near pinniped rookeries
in autumn and winter, sharks avoided the surface and used water to 50 m depth, consistent with a silhouette-based hunting
strategy. Offshore migrations were initiated during November–March and followed periods of decreasing pinniped abundance.
Migrations were highly directed, taking 23 ± 5 days to reach the offshore focal area along similar paths among sharks and
years, defining a migration corridor. Sharks exhibited a broad depth distribution (0–644 m) in the offshore focal area, and
remained there for up to 167 days during spring and summer, though primary productivity and fishery data suggest that forage
resources are scarcer there than in other regions of the eastern North Pacific. Archival data from one shark revealed intensive
oscillatory movements while in the offshore focal area, a behavior that may be related to foraging or mating. Sharks traveling
to Hawaii remained near the islands up to 122 days, potentially feeding on pelagic fishes and marine mammals that concentrate
around the islands.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
175.
单甲脒在土壤中的降解及持久性研究 总被引:3,自引:0,他引:3
本文对四种不同类型土壤中单甲脒及其盐酸盐在厌氧与好氧条件下的降解动态及其残留进行了研究。结果表明单甲脒及其盐酸盐均属不稳定的化合物,单甲脒在土壤中的半衰期为4.6-9.1d,其盐酸盐的半衰期为2.0-6.2d。结果还表明单甲脒盐酸盐在厌氧条件下较在好氧条件下降解缓慢;在厌氧条件时,土壤的pH值对其降解影响较大。在相同条件下,单甲脒比它的盐酸盐酸盐降解慢,其降解速率与土壤pH值无关。 相似文献
176.
GeochemicalmigrationofarsenicanditsenvironmentalefectWengHuanxin,LanXiangDepartmentofEarthSciences,ZhejiangUniversity,Hangzho... 相似文献
177.
178.
179.
180.
Nocturnal chemistry can play an important role in determining the initial morning conditions for daytime chemistry in urban areas. However, the impact on daytime O3 levels is difficult to assess as the suppression of vertical trace gas transport leads to highly altitude dependent nocturnal chemistry, in particular with respect to the removal and conversion of nitrogen oxides (NOx) and volatile organic compounds (VOC). One-dimensional (1-D) chemical transport model calculations for different nighttime vertical stabilities and different ozone formation regimes (i.e. NOx- vs. VOC-sensitive) were performed assuming a 1000 m high daytime boundary layer and a growing nocturnal boundary layer reaching 200 m height at the end of the night. Exclusion of NO3 chemistry from the model leads to daytime O3 concentration changes from ?4% to +16% for different O3 sensitivities. In all cases strong nocturnal vertical concentration profiles of NOx, O3, NO3 and N2O5 and a dependence of these profiles on vertical stability were found at night. The nocturnal NOx loss averaged over the lowest 1000 m changes by 9–24% for different vertical stabilities and ozone sensitivities. The impact of nocturnal vertical stability leads to 7–12% difference in O3 concentration in the morning and ~0–2.5% in the afternoon. 相似文献