全文获取类型
收费全文 | 290篇 |
免费 | 1篇 |
国内免费 | 1篇 |
专业分类
安全科学 | 13篇 |
废物处理 | 9篇 |
环保管理 | 25篇 |
综合类 | 90篇 |
基础理论 | 50篇 |
环境理论 | 1篇 |
污染及防治 | 79篇 |
评价与监测 | 13篇 |
社会与环境 | 12篇 |
出版年
2023年 | 3篇 |
2022年 | 2篇 |
2020年 | 4篇 |
2019年 | 3篇 |
2018年 | 11篇 |
2017年 | 6篇 |
2016年 | 16篇 |
2015年 | 12篇 |
2014年 | 8篇 |
2013年 | 23篇 |
2012年 | 12篇 |
2011年 | 28篇 |
2010年 | 5篇 |
2009年 | 16篇 |
2008年 | 11篇 |
2007年 | 12篇 |
2006年 | 12篇 |
2005年 | 14篇 |
2004年 | 11篇 |
2003年 | 10篇 |
2002年 | 9篇 |
2001年 | 8篇 |
2000年 | 3篇 |
1999年 | 3篇 |
1996年 | 3篇 |
1992年 | 3篇 |
1991年 | 3篇 |
1986年 | 2篇 |
1985年 | 2篇 |
1982年 | 2篇 |
1978年 | 2篇 |
1962年 | 1篇 |
1961年 | 1篇 |
1955年 | 1篇 |
1954年 | 1篇 |
1953年 | 2篇 |
1951年 | 3篇 |
1948年 | 1篇 |
1944年 | 1篇 |
1943年 | 1篇 |
1942年 | 1篇 |
1941年 | 1篇 |
1935年 | 1篇 |
1933年 | 1篇 |
1932年 | 2篇 |
1929年 | 1篇 |
1928年 | 1篇 |
1922年 | 1篇 |
1917年 | 1篇 |
1914年 | 1篇 |
排序方式: 共有292条查询结果,搜索用时 15 毫秒
101.
102.
Philipp Balzer Klaus Peter Rippe Peter Schaber 《Journal of Agricultural and Environmental Ethics》2000,13(1):7-27
The 1992 incorporation of an article by referendum in the SwissConstitution mandating that the federal government issue regulations onthe use of genetic material that take into account the dignity ofnonhuman organism raises philosophical questions about how we shouldunderstand what is meant by ``the dignity of nonhuman animals,' andabout what sort of moral demands arise from recognizing this dignitywith respect to their genetic engineering. The first step in determiningwhat is meant is to clarify the difference between dignity when appliedto humans and when applied to nonhumans. Several conceptions of humandignity should be rejected in favor of a fourth conception: the rightnot to be degraded. This right implies that those who have it have thecognitive capacities that are prerequisite for self-respect. In the caseof nonhuman organisms that lack this capacity, respecting their dignityrequires the recognition that their inherent value, which is tied totheir abilities to pursue their own good, be respected. This value isnot absolute, as it is in the case of humans, so it does not prohibitbreeding manipulations that make organisms more useful to humans. But itdoes restrict morally how sentient animals can be used. In regard togenetic engineering, this conception requires that animals be allowedthe uninhibited development of species specific functions, a positionshared by Holland and Attfield, as opposed to the Original Purposeconception proposed by Fox and the Integrity of the Genetic Make-upposition proposed by Rolston. The inherent value conception of dignity,as here defended, is what is meant in the Swiss Constitution article. 相似文献
103.
Marianne Olufsen Augustine Arukwe 《Environmental science and pollution research international》2015,22(22):17350-17366
104.
Future agriculture with minimized phosphorus losses to waters: Research needs and direction 总被引:3,自引:0,他引:3
Andrew N. Sharpley Lars Bergström Helena Aronsson Marianne Bechmann Carl H. Bolster Katarina Börling Faruk Djodjic Helen P. Jarvie Oscar F. Schoumans Christian Stamm Karin S. Tonderski Barbro Ulén Risto Uusitalo Paul J. A. Withers 《Ambio》2015,44(2):163-179
The series of papers in this issue of AMBIO represent technical presentations made at the 7th International Phosphorus Workshop (IPW7), held in September, 2013 in Uppsala, Sweden. At that meeting, the 150 delegates were involved in round table discussions on major, predetermined themes facing the management of agricultural phosphorus (P) for optimum production goals with minimal water quality impairment. The six themes were (1) P management in a changing world; (2) transport pathways of P from soil to water; (3) monitoring, modeling, and communication; (4) importance of manure and agricultural production systems for P management; (5) identification of appropriate mitigation measures for reduction of P loss; and (6) implementation of mitigation strategies to reduce P loss. This paper details the major challenges and research needs that were identified for each theme and identifies a future roadmap for catchment management that cost-effectively minimizes P loss from agricultural activities. 相似文献
105.
106.
Lotte Hatt Katarina Ravn Line Dahl Jeppesen Bolette Hestbek Nicolaisen Inga Baasch Christensen Ripudaman Singh Palle Schelde Simon Horsholt Thomsen Rikke Christensen Marianne Sinding Laura Vase Marianne Oestergaard Marie Bender Ruggard Hanne S. Jensen Helle Mogensen Niels Uldbjerg Naja Becher Sara Markholt Puk Sandager Lars Henning Pedersen Ida Vogel 《黑龙江环境通报》2023,43(7):854-864
Objectives
We aimed to compare cell-based NIPT (cbNIPT) to chorionic villus sampling (CVS) and to examine the test characteristics of cbNIPT in the first clinical validation study of cbNIPT compared to cell-free NIPT (cfNIPT).Material and Methods
Study 1: Women (N = 92) who accepted CVS were recruited for cbNIPT (53 normal and 39 abnormal). Samples were analyzed with chromosomal microarray (CMA). Study 2: Women (N = 282) who accepted cfNIPT were recruited for cbNIPT. cfNIPT was analyzed using sequencing and cbNIPT by CMA.Results
Study 1: cbNIPT detected all aberrations (32/32) found in CVS: trisomies 13, 18 and 21 (23/23), pathogenic copy number variations (CNVs) (6/6) and sex chromosome aberrations (3/3). cbNIPT detected 3/8 cases of mosaicism in the placenta. Study 2: cbNIPT detected all trisomies found with cfNIPT (6/6) and had no false positive (0/246). One of the three CNVs called by cbNIPT was confirmed by CVS but was undetected by cfNIPT, two were false positives. cbNIPT detected mosaicism in five samples, of which two were not detected by cfNIPT. cbNIPT failed in 7.8% compared to 2.8% in cfNIPT.Conclusion
Circulating trophoblasts in the maternal circulation provide the potential of screening for aneuploidies and pathogenic CNVs covering the entire fetal genome. 相似文献107.
Participatory processes in general and also in relation to managing landscape issues are gathering importance mostly due to arguments surrounding legitimacy and effectiveness in decision-making. The main aim of this research, based on a transaction costs perspective, is to present an integrated analytical framework in order to determine individual efforts (time, money), benefits and risks of participants in landscape co-management processes. Furthermore a reflection on the analytical approach developed and arising lessons to be learned for landscape co-management are presented. In the analytical framework benefit-components comprise of factors such as 'contributing to landscape maintenance/development and nature protection', 'representing one's interest group', 'co-deciding on relevant topics', 'providing and broadening one's knowledge' and 'building networks'. The risks of participation are related to a lack of information and agreements, missing support and actual decision-making power. The analytical framework is applied to two case studies in Austria: an EU LIFE-Nature project and a Cultural Landscape Project of the Provincial Government of Lower Austria. Analysis of the effort-benefit-relations provides an indication for a more effective design of co-management. Although the processes are rated as quite adequate, there is a low willingness of participants to commit additional time to co-management processes. In contrast to the Cultural Landscape Project, in the LIFE-Nature project, professionally involved persons participate next to partly and full volunteers. These uneven conditions of participation and an unfair distribution of transaction costs, jeopardize the promising chances co-management bears for landscape governance. 相似文献
108.
109.
Veith Becker Anssi Myrttinen Philipp Blum Robert van Geldern Johannes A.C. Barth 《International Journal of Greenhouse Gas Control》2011,5(5):1250-1258
Stable carbon isotopes are important tools to assess potential storage sites for CO2, as they allow the quantification of ionic trapping via isotope mass balances. In deep geological formations high p/T conditions need to be considered, because CO2 dissolution, equilibrium constants and isotope fractionation of dissolved inorganic carbon (DIC) depend on temperature, pressure and solute composition. After reviewing different approaches to account for these dependencies, an expanded scheme is presented for speciation and carbon isotope fractionation of DIC and dissolution of CaCO3 for pCO2 up to 100 bar, pH down to 3 and temperatures of up to 200 °C. The scheme evaluates the influence of respective parameters on isotope ratios during CO2 sequestration. The pCO2 and pH are the dominant controlling factors in the DIC/δ13C/pH system. The fugacity of CO2 has major impact on DIC concentrations at temperatures below 100 °C at high pCO2. Temperature dependency of activities and equilibrium dominates at temperatures above 100 °C. Isotope ratios of DIC are expected to be about 1–2‰ more depleted in 13C compared to the free CO2 at pCO2 values above 10 bar. This depletion is controlled by carbon isotope fractionation between CO2 and H2CO3* which is the dominant species of DIC at the resulting pH below 5. 相似文献
110.
Plants control the seasonal dynamics of microbial N cycling in a beech forest soil by belowground C allocation 总被引:1,自引:0,他引:1
Kaiser C Fuchslueger L Koranda M Gorfer M Stange CF Kitzler B Rasche F Strauss J Sessitsch A Zechmeister-Boltenstern S Richter A 《Ecology》2011,92(5):1036-1051
Soil microbes in temperate forest ecosystems are able to cycle several hundreds of kilograms of N per hectare per year and are therefore of paramount importance for N retention. Belowground C allocation by trees is an important driver of seasonal microbial dynamics and may thus directly affect N transformation processes over the course of the year. Our study aimed at unraveling plant controls on soil N cycling in a temperate beech forest at a high temporal resolution over a time period of two years, by investigating the effects of tree girdling on microbial N turnover. In both years of the experiment, we discovered (1) a summer N mineralization phase (between July and August) and (2) a winter N immobilization phase (November-February). The summer mineralization phase was characterized by a high N mineralization activity, low microbial N uptake, and a subsequent high N availability in the soil. During the autumn/winter N immobilization phase, gross N mineralization rates were low, and microbial N uptake exceeded microbial N mineralization, which led to high levels of N in the microbial biomass and low N availability in the soil. The observed immobilization phase during the winter may play a crucial role for ecosystem functioning, since it could protect dissolved N that is produced by autumn litter degradation from being lost from the ecosystem during the phase when plants are mostly inactive. The difference between microbial biomass N levels in winter and spring equals 38 kg N/ha and may thus account for almost one-third of the annual plant N demand. Tree girdling strongly affected annual N cycling: the winter N immobilization phase disappeared in girdled plots (microbial N uptake and microbial biomass N were significantly reduced, while the amount of available N in the soil solution was enhanced). This was correlated to a reduced fungal abundance in autumn in girdled plots. By releasing recently fixed photosynthates to the soil, plants may thus actively control the annual microbial N cycle. Tree belowground C allocation increases N accumulation in microorganisms during the winter which may ultimately feed back on plant N availability in the following growing season. 相似文献