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181.
182.
We conducted two studies addressing abstaining from voting in union representation elections. In Study 1 of a faculty representation election, we showed that compared to voters abstainers possessed less extreme work and union attitudes, believed less in the ability of their vote to affect the election outcomes, and were less involved in the election (e.g., less interested, felt less responsibility to vote). To assess the practical utility of these findings, Study 2 used vignettes in a 2 (traditional bread‐and‐butter issues) × 2 (emerging issues related to fairness) × 2 (voting instrumentality) × 2 (responsibility to vote) experimental manipulation. Results showed that the likelihood of abstaining is reduced when efforts to emphasize the responsibility to vote are presented together with information on both traditional and emerging issues. The two studies show why people abstain from voting in union representation elections, and suggest how abstaining might be reduced. Conceptual implications, practical interventions and research directions raised by the two studies are discussed. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
183.
Larissa Swedell Liane Leedom Julian Saunders Mathew Pines 《Behavioral ecology and sociobiology》2014,68(2):263-273
Fundamental reproductive interests dictate that females generally benefit most from mate selectivity and males from mate quantity. This can create conflict between the sexes and result in sexual coercion: male use of aggression to garner mating success at a cost to females. Potential fitness costs of sexual coercion, however, can be difficult to measure. Here, we demonstrate benefits to males and costs to females of female defense polygyny in wild hamadryas baboons, cercopithecoid primates in which females are coercively transferred among social units by males, restricting both female choice and bonding among female kin. Of all coercive transfers (takeovers) of females with young infants, 67 % were followed by infant mortality, which was significantly more likely to occur after takeovers than at other times. As expected, infant mortality decreased time to subsequent conception but lengthened intervals between surviving infants. Following infant survival, whether a female had experienced a takeover after the previous birth was a significant predictor of subsequent interbirth interval, with interbirth intervals of females remaining with the same male between births being significantly shorter than those of females incurring takeovers between births. Together, these results reveal that takeovers increase the chance of infant mortality while delaying subsequent conception. Male-driven female defense polygyny in this species is thus costly to females in two ways. These results demonstrate that reproductive strategies benefitting males can evolve despite substantial costs to females. These costs may be mitigated over the long term, however, by female counterstrategies and protective behavior by males. 相似文献
184.
185.
Mixed contamination by organic and inorganic compounds in soil is a serious problem for remediation. Most laboratory studies and field-scale trials focused on individual contaminant in the past. For concurrent bioremediation by biodegradation and bioleaching processes, we tested metal-reducing microorganism, Geobacter metallireducens. In order to prove the feasibility of the coupled process, multiple-contaminated soil was prepared. Mineralogical analyses have shown the existence of labile forms of As(V) as amorphous and/or weakly sorbed phases in the secondary Fe oxides. In the biotic experiment using G. metallireducens, biodegradation of toluene and bioleaching of As by bacteria were observed simultaneously. Bacteria accelerated the degradation rate of toluene with reductive dissolution of Fe and co-dissolution of As. Although there have been many studies showing each individual process, we have shown here that the idea of concurrent microbial reaction is feasible. However, for the practical use as a remediation technology, more details and multilateral evaluations are required in future studies. 相似文献
186.
Multi-scale marine biodiversity patterns inferred efficiently from habitat image processing 总被引:1,自引:0,他引:1
Mellin C Parrott L Andréfou?t S Bradshaw CJ MacNeil MA Caley MJ 《Ecological applications》2012,22(3):792-803
Cost-effective proxies of biodiversity and species abundance, applicable across a range of spatial scales, are needed for setting conservation priorities and planning action. We outline a rapid, efficient, and low-cost measure of spectral signal from digital habitat images that, being an effective proxy for habitat complexity, correlates with species diversity and requires little image processing or interpretation. We validated this method for coral reefs of the Great Barrier Reef (GBR), Australia, across a range of spatial scales (1 m to 10 km), using digital photographs of benthic communities at the transect scale and high-resolution Landsat satellite images at the reef scale. We calculated an index of image-derived spatial heterogeneity, the mean information gain (MIG), for each scale and related it to univariate (species richness and total abundance summed across species) and multivariate (species abundance matrix) measures of fish community structure, using two techniques that account for the hierarchical structure of the data: hierarchical (mixed-effect) linear models and distance-based partial redundancy analysis. Over the length and breadth of the GBR, MIG alone explained up to 29% of deviance in fish species richness, 33% in total fish abundance, and 25% in fish community structure at multiple scales, thus demonstrating the possibility of easily and rapidly exploiting spatial information contained in digital images to complement existing methods for inferring diversity and abundance patterns among fish communities. Thus, the spectral signal of unprocessed remotely sensed images provides an efficient and low-cost way to optimize the design of surveys used in conservation planning. In data-sparse situations, this simple approach also offers a viable method for rapid assessment of potential local biodiversity, particularly where there is little local capacity in terms of skills or resources for mounting in-depth biodiversity surveys. 相似文献
187.
Evolutionary simulation-optimization (ESO) techniques can be adapted to model a wide variety of problem types in which system components are stochastic. Grey programming (GP) methods have been previously applied to numerous environmental planning problems containing uncertain information. In this paper, ESO is combined with GP for policy planning to create a hybrid solution approach named GESO. It can be shown that multiple policy alternatives meeting required system criteria, or modelling-to-generate-alternatives (MGA), can be quickly and efficiently created by applying GESO to this case data. The efficacy of GESO is illustrated using a municipal solid waste management case taken from the regional municipality of Hamilton-Wentworth in the Province of Ontario, Canada. The MGA capability of GESO is especially meaningful for large-scale real-world planning problems and the practicality of this procedure can easily be extended from MSW systems to many other planning applications containing significant sources of uncertainty. 相似文献
188.
Food Supply Chain Governance And Public Health Externalities: Upstream Policy Interventions And The UK State 总被引:1,自引:0,他引:1
David Barling 《Journal of Agricultural and Environmental Ethics》2007,20(3):285-300
Contemporary food supply chains are generating externalities with high economic and social costs, notably in public health
terms through the rise in diet-related non-communicable disease. The UK State is developing policy strategies to tackle these
public health problems alongside intergovernmental responses. However, the governance of food supply chains is conducted by,
and across, both private and public spheres and within a multilevel framework. The realities of contemporary food governance
are that private interests are key drivers of food supply chains and have institutionalized a great deal of standards-setting
and quality, notably from their locations in the downstream and midstream sectors. The UK State is designing some downstream and some midstream interventions to ameliorate the public health impacts of current food consumption patterns in England. The UK State has not
addressed upstream interventions towards public health diet at the primary food production and processing stages, although traditionally it
has shaped agricultural policy. Within the realities of contemporary multilevel governance, the UK State must act within the
contexts set by the international regimes of the Common Agricultural Policy and the World Trade Organization agreements, notably
on agriculture. The potential for further upstream agricultural policy reform is considered as part of a wider policy approach
to address the public health externalities issuing from contemporary food supply chains within this multilevel governance
context. 相似文献
189.
黑河下游额济纳河沿岸绿洲是阿拉善独特的三道生态屏障——额济纳河沿岸绿洲、横贯东西绵延800多公里梭梭林带、贺兰山天然次生林之一。三道生态屏障同时也是我国西北地区的一条重要生态防线。但由于气候旱化和对动植物资源的不合理开发利用等因素的共同作用,目前黑河下游额济纳河沿岸绿洲生态功能退化严重,生态防护功能受损。为改善黑河下游额济纳河沿岸绿洲的生态环境状况,恢复额济纳绿洲生态功能,需要尊重自然规律,遵循生态学原理,在可持续发展原则指导下合理开发、利用自然资源,加大环保监管力度,综合运用经济、工程、法制、宣传等规划管理措施和手段加强生态环境保护与建设,保护额济纳绿洲生态屏障。 相似文献
190.
Maryam Ghiasi Christine Armour Mark Walker Nicole Shaver Alexandria Bennett Julian Little 《黑龙江环境通报》2023,43(1):62-71
In recent years, as the implementation and use of Non-Invasive Prenatal Testing (NIPT) have increased, the cost of the test has been decreasing. The cost of NIPT is expected to fall further in the upcoming years. As a result of the decreasing cost of NIPT, many jurisdictions may change their prenatal screening policies toward abandoning serum-based screening and instead, implement and support NIPT as the first-tier screening for all women. There are several concerns in replacing first-trimester screening with NIPT. In this scoping review, we aimed to map the existing knowledge about possible issues in the systematic implementation of NIPT as the primary method of first-tier screening and to assess if any jurisdiction has altered its policy and discontinued serum-based prenatal screening in exchange for NIPT. The Medline database (Ovid) and Google Scholar was searched and all the studies discussing, investigating, or reporting on the systematic implementation of NIPT as the primary method of first-tier screening were included. All the studies went through a two-stage screening process and included full-text articles were reviewed. We did not find any articles indicating a country or region that replaced traditional prenatal screening by NIPT. The included articles were charted, and the data about the possible issues in the systematic implementation of NIPT as the primary method of first-tier screening are summarized narratively and presented in tables in four categories. The findings of this scoping review may be informative for stakeholders and policymakers regarding recent changes in NIPT implementation policies around the world and may aid with developing policy for NIPT implementation with a broader perspective. 相似文献