全文获取类型
收费全文 | 5555篇 |
免费 | 57篇 |
国内免费 | 27篇 |
专业分类
安全科学 | 94篇 |
废物处理 | 366篇 |
环保管理 | 382篇 |
综合类 | 793篇 |
基础理论 | 1164篇 |
环境理论 | 6篇 |
污染及防治 | 1952篇 |
评价与监测 | 524篇 |
社会与环境 | 341篇 |
灾害及防治 | 17篇 |
出版年
2023年 | 59篇 |
2022年 | 182篇 |
2021年 | 168篇 |
2020年 | 78篇 |
2019年 | 84篇 |
2018年 | 201篇 |
2017年 | 172篇 |
2016年 | 283篇 |
2015年 | 162篇 |
2014年 | 307篇 |
2013年 | 535篇 |
2012年 | 350篇 |
2011年 | 372篇 |
2010年 | 274篇 |
2009年 | 219篇 |
2008年 | 314篇 |
2007年 | 323篇 |
2006年 | 273篇 |
2005年 | 187篇 |
2004年 | 162篇 |
2003年 | 142篇 |
2002年 | 137篇 |
2001年 | 77篇 |
2000年 | 61篇 |
1999年 | 51篇 |
1998年 | 24篇 |
1997年 | 18篇 |
1996年 | 16篇 |
1995年 | 33篇 |
1994年 | 20篇 |
1993年 | 15篇 |
1992年 | 10篇 |
1991年 | 8篇 |
1990年 | 12篇 |
1989年 | 10篇 |
1970年 | 6篇 |
1967年 | 9篇 |
1966年 | 11篇 |
1965年 | 15篇 |
1964年 | 29篇 |
1963年 | 12篇 |
1962年 | 17篇 |
1961年 | 11篇 |
1960年 | 9篇 |
1959年 | 26篇 |
1958年 | 26篇 |
1957年 | 17篇 |
1956年 | 14篇 |
1955年 | 18篇 |
1954年 | 7篇 |
排序方式: 共有5639条查询结果,搜索用时 46 毫秒
911.
912.
913.
914.
915.
916.
Lenka Okenicová Mária Žemberyová Simona Procházková 《Environmental Chemistry Letters》2016,14(1):67-77
Some trace metals are highly toxic for the environment. There is therefore a need for reliable methods for the determination of metals at trace levels. To this end, new sample pretreatment methods such as separation, preconcentration and speciation prior to the determination of metal ions have developed rapidly. Biosorption has become a major tool for solid-phase extraction methods. This review covers selected biosorbents such as algae, bacteria, filamentous fungi and yeasts, as new sorbents used in the solid-phase extraction of metal ions from various water sample matrices. A survey of the literature over 2004-2014 shows possible applications of selected new sorbents available for use in trace metal analysis in waters using solidphase extraction. We highlight the preconcentration of the toxic elements prior to their determination by atomic spectrometry. 相似文献
917.
Marí a Fernanda HORST Veró nica LASSALLE Marí a Lujá n FERREIRA 《Frontiers of Environmental Science & Engineering》2015,9(5):746
Nanosized magnetite has emerged as an adsorbent of pollutants in water remediation. Nanoadsorbents include magnetic iron oxide and its modifiers/stabilizers, such as carbon, silica, clay, organic moieties (polymers, aminoacids, and fatty acids) and other inorganic oxides. This review is focused on the recent developments on the synthesis and use of magnetic nanoparticles and nanocomposites in the treatment of contaminated water. The emphasis is on the influence of the iron oxide modifiers on some properties of interest such as size, BET area, and magnetization. The characteristics of these nanomaterials are related to their ability to eliminate heavy metal ions and dyes from wastewater. Comparative analysis of the actual literature was performed aiming to present the magnetic material, its preparation methodology and performance in the elimination of the selected pollutants. Vast information has been properly summarized according to the materials, their properties and preferential affinity for selected contaminants. The mechanisms governing nanomaterial’s formation as well as the interactions with heavy metals and dyes have been carefully analyzed and associated to their efficiency. 相似文献
918.
A. P. Rodríguez-Troncoso E. Carpizo-Ituarte D. T. Pettay M. E. Warner A. L. Cupul-Magaña 《Marine Biology》2014,161(1):131-139
Coral bleaching events are associated with abnormal increases in temperature, such as those produced during El Niño. Recently, a breakdown in the coral–dinoflagellate (genus Symbiodinium) endosymbiosis has been documented in corals exposed to anomalously cold-water temperatures associated with La Niña events. Given the ecological significance of such events, as well as the threat of global climate change, surprisingly little is known about the physiological response of corals to cold stress. This study evaluated some physiological effects of continuous temperature decline in colonies of the eastern Pacific reef-building coral Pocillopora verrucosa. Twenty days of incubation at 18.5–19.0 °C resulted in a substantial decrease in holobiont lipid and Chla content, as well as an increase in Symbiodinium density. These observations suggest a combination of symbiont acclimation due to the temperature decline and reallocation of carbon toward algal growth as opposed to translocation to the host coral. With a decreased availability of symbiont-derived carbon, the coral likely catabolized storage lipids in order to survive the stress event. Despite this stress and some tissue necrosis, no mortality was noted and corals recovered quickly when returned to the ambient temperature. As these results are in marked contrast to similar studies investigating elevated temperature on this coral from this same location, Pocillopora in the Mexican Central Pacific may be more prone to long-term damage and mortality during periods of ocean warming as opposed to ocean cooling. 相似文献
919.
Dóra B. Huszár Rasmus S. Larsen Sarah Carlsen Jacobus J. Boomsma Jes Søe Pedersen 《Behavioral ecology and sociobiology》2014,68(11):1859-1870
Ant supercolonies (large networks of interconnected nests) represent the most extreme form of multi-queen breeding (polygyny) and have been found across ant lineages, usually in specific long-term stable populations. Many studies on the genetic population structure and demography of ant supercolonies have been done in recent decades, but they have lacked multicolonial control patches with separated colonies headed by a single or few queens so the origin of the supercolonial trait syndrome has remained enigmatic. Here, we set out to compare sympatric supercolonial and multicolonial patches in two natural Danish populations of the common red ant Myrmica rubra. We used DNA microsatellites to reconstruct genetic colony/population structure and obtained morphological and density measurements to estimate life history and ecology covariates. We found that supercolonies in both populations completely dominated their patches whereas colonies in multicolonial patches coexisted with other ant species. Supercolony patches had very low genetic differentiation between nests, negligible relatedness within nests, and lower inbreeding than multicolonial patches, but there were no significant morphological differences. One population also had nests that approached true outbred monogyny with larger workers and males but smaller queens than in the two other social nest types. Our results suggest that once smaller colonies start to adopt additional queens, they also gain the potential to ultimately become supercolonial when the habitat allows rapid expansion through nest budding. This is relevant for understanding obligate polygyny in ants and for appreciating how and why introduced North American populations of M. rubra have recently become invasive. 相似文献
920.
An evolutionarily fundamental, yet rarely examined, aspect of host–parasite arms races is the repeatability of individual host responses to parasitism. We examined the repeatability of egg ejection, and the latency to eject, across a time-scale of days (within one breeding attempt), weeks and months (between breeding attempts within one breeding season), and years (across different breeding seasons). The ejection of non-mimetic model eggs by European blackbirds, Turdus merula, showed overall high repeatability (r?~?0.70) and, similar to empirical patterns on most other behavioral traits already studied, showed decreasing repeatability with time. In contrast, latency to ejection showed negligible repeatability overall (r ~0.20) and did not change with time. Ejection rates, latencies to ejection and the repeatability of egg ejection did not differ between young and old females. Previous experience with experimentation (number of model eggs the female received before the focal trial) marginally non-significantly covaried with egg ejection (positively) and with latency to egg ejection (negatively). Repeatability estimates for both egg ejection and latency to egg ejection at the within one breeding attempt time-scale did not statistically differ from those reported in a previous study of a different blackbird population (introduced population in New Zealand). To our knowledge, this is the first comparison of behavioral repeatability between a native vs. introduced population of any animal species. 相似文献