全文获取类型
收费全文 | 1019篇 |
免费 | 11篇 |
国内免费 | 15篇 |
专业分类
安全科学 | 43篇 |
废物处理 | 40篇 |
环保管理 | 122篇 |
综合类 | 190篇 |
基础理论 | 170篇 |
环境理论 | 1篇 |
污染及防治 | 347篇 |
评价与监测 | 70篇 |
社会与环境 | 47篇 |
灾害及防治 | 15篇 |
出版年
2023年 | 18篇 |
2022年 | 22篇 |
2021年 | 34篇 |
2020年 | 27篇 |
2019年 | 23篇 |
2018年 | 48篇 |
2017年 | 48篇 |
2016年 | 57篇 |
2015年 | 37篇 |
2014年 | 60篇 |
2013年 | 72篇 |
2012年 | 61篇 |
2011年 | 81篇 |
2010年 | 52篇 |
2009年 | 42篇 |
2008年 | 63篇 |
2007年 | 58篇 |
2006年 | 63篇 |
2005年 | 45篇 |
2004年 | 34篇 |
2003年 | 18篇 |
2002年 | 19篇 |
2001年 | 9篇 |
2000年 | 9篇 |
1999年 | 2篇 |
1998年 | 3篇 |
1997年 | 7篇 |
1996年 | 2篇 |
1995年 | 5篇 |
1994年 | 2篇 |
1993年 | 3篇 |
1992年 | 1篇 |
1991年 | 2篇 |
1990年 | 1篇 |
1989年 | 2篇 |
1988年 | 1篇 |
1986年 | 2篇 |
1984年 | 1篇 |
1966年 | 1篇 |
1961年 | 1篇 |
1960年 | 1篇 |
1959年 | 1篇 |
1958年 | 1篇 |
1957年 | 1篇 |
1954年 | 3篇 |
1951年 | 1篇 |
1936年 | 1篇 |
排序方式: 共有1045条查询结果,搜索用时 15 毫秒
911.
Within-group conflict may influence the degree to which individuals within a group cooperate. For example, the most dominant
individuals within a group often gain access to the best resources and may be less inclined to perform risky tasks. We monitored
space use and division of labor among all workers in three colonies of bumblebees, Bombus impatiens, during the ergonomic and queenless phases of their colony cycle. We then measured the two largest oocytes in each worker
to estimate each individual's reproductive potential at the end of the colony cycle. We show that workers that remained farther
from the queen while inside the nest and avoided risky or more energy-expensive tasks during the ergonomic phase developed
larger oocytes by the end of the colony cycle. These individuals also tended to be the largest, oldest workers. After the
queen died, these workers were more likely than their nestmates to increase brood incubation. Our results suggest that inactive
bumblebees may be storing fat reserves to later develop reproductive organs and that the spatial organization of workers inside
the nest, particularly the distance workers maintain from the queen, may predict which individuals will later have the greatest
reproductive potential in the colony. 相似文献
912.
Elvira Morote María Pilar Olivar Anna Bozzano Fernando Villate Ibon Uriarte 《Marine Biology》2011,158(6):1349-1361
Feeding ecology was analysed for the first time in the larvae of the European hake (Merluccius merluccius) to determine whether their diet and selectivity were constrained by environmental conditions and how these feeding characteristics
were related to ontogeny, prey availability and visual capabilities. Larvae collected during both day and night were analysed,
and it was found that feeding incidence was high, regardless of the time of day. Examination of the visual system corroborated
the hypothesis that hake larvae should be able to cope with a wide range of photic conditions and to forage even at low light
intensity. A clear preference for adult calanoid copepods and, especially, for Clausocalanus spp. was observed in all sizes analysed. Prey number increased with larval size, but prey size did not. This finding indicates
that hake larvae behave as selective and specialist predators that consume an increasing number of prey rather than larger
prey during larval growth. 相似文献
913.
Rupert Seidl Paulo M. Fernandes Teresa F. FonsecaFrançois Gillet Anna Maria JönssonKatarína Mergani?ová Sigrid NethererAlexander Arpaci Jean-Daniel BontempsHarald Bugmann Jose Ramon González-OlabarriaPetra Lasch Céline MeredieuFrancisco Moreira Mart-Jan SchelhaasFrits Mohren 《Ecological modelling》2011,222(4):903-924
914.
The infinite dimensional model (IDM) is an approach that has been developed for the analyses of phenotypic variation in function valued traits such as growth trajectories and continuous reaction norms. This model is particularly suited for the analysis of the potential and the constraints for growth to evolve under selection on body size. Despite of its applicability to a broad range of study systems IDM has only been applied in a handful of studies, as it is mathematically demanding for scientists not familiar with quantitative genetics methods. Here, we present a user-friendly R implementation of IDM, demonstrate its performance with growth data on nine-spined stickleback (Pungitius pungitius). In addition to rearing experiments, individual based size-at-age trajectories are often measured in wild in mark-recapture studies or estimated retrospectively from scales or bones. Therefore, our R implementation of IDM should be applicable to many studies conducted in wild and in a lab, and be useful by making the methodologically challenging IDM approach more easily accessible also in the fields where quantitative genetics methods are less standardly used. 相似文献
915.
Filipkowska A Kowalewska G Pavoni B Łęczyński L 《Environmental monitoring and assessment》2011,182(1-4):455-466
Sediment samples were collected in two Polish ports of international significance--the Port of Gdańsk and the Port of Gdynia (Gulf of Gdańsk, Baltic Sea)--in order to assess their butyltin and phenyltin contamination; this was done in 2008, just after the total ban on using harmful organotins in antifouling paints on ships came into force. Altogether, 21 sampling stations were chosen to present a diversity of port sites: from port canals and shipyards to anchorages and dumping sites. The organic carbon content and grain size of all the sediment samples were determined, and some environmental parameters (oxygen content, salinity) were measured as well. Total concentrations of butyltin compounds in sediment samples were very different and ranged between 1 and 18,520 ng Sn g(-1) d.w. Phenyltin contents were distinctly lower and ranged from below the limit of detection (most samples) to 660 ng Sn g(-1) d.w. The highest concentrations of organotins were found in the shipyards, the maximum total organotin content (19,180 ng Sn g(-1) d.w.) being found in the Gdańsk Ship Repair Yard 'Remontowa'. Butyltin degradation indices indicate a recent tributyltin input into the port sediments. The results obtained from this work prove that the international ban on using organotins may not be enough to protect the marine environment. It is necessary to monitor organotin contamination in ports and establish concentration limits of these compounds for the disposal of dredged material at sea. 相似文献
916.
G?ran St?hl Anna Allard Per-Anders Esseen Anders Glimsk?r Anna Ringvall Johan Svensson Sture Sundquist Pernilla Christensen ?sa Gallegos Torell Mats H?gstr?m Kjell Lagerqvist Liselott Marklund Bj?rn Nilsson Ola Inghe 《Environmental monitoring and assessment》2011,173(1-4):579-595
The landscape-level and multiscale biodiversity monitoring program National Inventory of Landscapes in Sweden (NILS) was launched in 2003. NILS is conducted as a sample-based stratified inventory that acquires data across several spatial scales, which is accomplished by combining aerial photo interpretation with field inventory. A total of 631 sample units are distributed across the land base of Sweden, of which 20% are surveyed each year. By 2007 NILS completed the first 5-year inventory phase. As the reinventory in the second 5-year phase (2008?C2012) proceeds, experiences and insights accumulate and reflections are made on the setup and accomplishment of the monitoring scheme. In this article, the emphasis is placed on background, scope, objectives, design, and experiences of the NILS program. The main objective to collect data for and perform analyses of natural landscape changes, degree of anthropogenic impact, prerequisites for natural biological diversity and ecological processes at landscape scale. Different environmental conditions that can have direct or indirect effects on biological diversity are monitored. The program provides data for national and international policy and offers an infrastructure for other monitoring program and research projects. NILS has attracted significant national and international interest during its relatively short time of existence; the number of stakeholders and cooperation partners steadily increases. This is constructive and strengthens the incentive for the multiscale monitoring approach. 相似文献
917.
Rygula A Jekiel K Szostak-Kot J Wrobel TP Baranska M 《Journal of environmental monitoring : JEM》2011,13(11):2983-2987
In this work we present the usefulness of FT-Raman spectroscopy for microbiological analysis of textiles. This technique was used for non-destructive identification of Escherichia coli bacteria on cotton and polyester fabrics. It was possible to discriminate between infected and non-infected materials. Moreover, this technique allowed detection of detergent traces as well as investigation of the influence of microorganisms on different textiles. Raman analysis supported by chemometrics (cluster analysis and principal component analysis) was shown to be a method for identification of textiles with inoculum of microorganisms in a short time. The results can be potentially used in the fabric industry and related areas. 相似文献
918.
The recent biomedical, technological, and normative changes have led healthcare organizations to the implementation of clinical governance as a way to ensure the best quality of care in an increasingly complex environment. Risk management is one of the most relevant aspects of clinical governance and approaches put forward in literature highlight the necessity to perform comprehensive analyses intended to uncover root causes of adverse events.Contributing to this field, the present paper applies Reason’s theory of failures to work out a systemic methodology to study risks impacting not only directly but also indirectly on patients. Also, the steps of such approach are organized around Human Reliability Assessment phases, in order to take into account the human component of healthcare systems. This framework is able to foster effective decision making about reducing failures and waste and to improve healthcare organizations’ maturity towards risk management.The developed methodology is applied to the pharmacy department of a large Italian hospital. An extensive validation in different healthcare settings is required to fully prove benefits and limitations. 相似文献
919.
920.