全文获取类型
收费全文 | 546篇 |
免费 | 3篇 |
专业分类
安全科学 | 27篇 |
废物处理 | 5篇 |
环保管理 | 142篇 |
综合类 | 76篇 |
基础理论 | 215篇 |
环境理论 | 4篇 |
污染及防治 | 25篇 |
评价与监测 | 13篇 |
社会与环境 | 22篇 |
灾害及防治 | 20篇 |
出版年
2023年 | 3篇 |
2022年 | 6篇 |
2021年 | 10篇 |
2020年 | 2篇 |
2019年 | 14篇 |
2018年 | 12篇 |
2017年 | 13篇 |
2016年 | 27篇 |
2015年 | 14篇 |
2014年 | 16篇 |
2013年 | 25篇 |
2012年 | 4篇 |
2011年 | 22篇 |
2010年 | 17篇 |
2009年 | 53篇 |
2008年 | 48篇 |
2007年 | 42篇 |
2006年 | 43篇 |
2005年 | 22篇 |
2004年 | 21篇 |
2003年 | 10篇 |
2002年 | 9篇 |
2001年 | 8篇 |
2000年 | 17篇 |
1999年 | 13篇 |
1998年 | 11篇 |
1997年 | 8篇 |
1996年 | 11篇 |
1995年 | 9篇 |
1994年 | 10篇 |
1993年 | 6篇 |
1992年 | 5篇 |
1991年 | 3篇 |
1990年 | 2篇 |
1987年 | 1篇 |
1986年 | 3篇 |
1985年 | 1篇 |
1984年 | 3篇 |
1983年 | 1篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1977年 | 1篇 |
1973年 | 1篇 |
排序方式: 共有549条查询结果,搜索用时 531 毫秒
391.
The household-recycling rate in the Borough of Burnley, England in 2001/2002 was only half the national average of 12%. This research employed both quantitative and qualitative surveys in order to ascertain whether householders’ attitudes to recycling were contributory factors to the generally poor recycling performance and to investigate other social, cultural and structural influences. The Borough has a large Asian–British population concentrated in two deprived wards where recycling rates are particularly low, so special attention was given to ascertaining their attitudes towards recycling.The quantitative survey comprised a postal questionnaire sent to a random sample of 360 households drawn from the electoral register. The qualitative survey consisted of group interviews with the Asian–British population at local community centres and focus groups attended by volunteers from the quantitative study.The findings suggest that householders are very willing to participate in recycling, as shown by the almost 80% claiming to recycle paper, but that local recycling services are too unreliable and inconvenient to allow them to do so comprehensively. Asian–British attitudes to recycling were found to be no different to those of the wider population, with their low participation being linked to the higher priorities imposed upon them by economic deprivation. The findings are broadly in line with those of the literature in that recycling participation tends to be higher among more affluent and older people, but lower among less affluent and younger households, probably due in part to the availability of both storage space and time, with the implication that the Borough's preponderance of terraced housing militates against a high recycling rate. Policy recommendations to local authorities include the provision of bespoke recycling services to suit the variety of residential conditions across the UK, and the provision of regular feedback to householders regarding recycling services and performance.Further research is needed to identify non-recyclers and to explore how householders’ underlying psychological, cultural and social attitudes to recycling impinge upon recycling and participation rates. 相似文献
392.
Mark Zeitoun Azza Dirar Asim El Moghraby Mohammad Jalal Hashim 《Local Environment》2019,24(2):129-145
ABSTRACTThis paper applies a “justice” lens to the struggle of the people displaced by the Merowe Dam in northern Sudan. Application of distributive, procedural, and representational aspects of justice exposes the dissatisfaction of the affected people with the government’s offer and execution of compensation. Consideration of social justice and the utility of norms in trans-national activism brings into sharp focus the difference in interests, and abilities of the many actors involved, and highlights the government’s tactics to divide the communities, and the social divisions sown. As the struggle develops, justice claims are seen to change towards less material issues, suggesting that an expanded and dynamic conception of justice is more helpful than narrow or time-bound conceptions. The findings are of relevance to communities facing possible displacement from dams planned nearby, not least of all for the insight provided on the effectiveness of different tactics in the struggle. 相似文献
393.
394.
John P. Kent Kenneth J. Murphy Finian J. Bannon Niamh M. Hynes Thomas J. Hayden 《Die Naturwissenschaften》2009,96(7):763-770
Testosterone (T) concentrations in many species are sensitive to seasonal changes and to changes in social conditions. However,
the effect of the natural or endogenous T increase in the juvenile on their social behaviour is not well understood. In this
study, T and behaviour were measured from the pro-social juvenile to the adult stage in semi-feral domestic fowl. During the
pro-social phase T levels and the distance chicks maintained between each other, i.e. inter-individual distance (IID) were
low. Then, as T increased, a corresponding increase in IID occurred and continued in males until dispersal to individual adult
male territories. In the new and initially stable adult social structure, T declined and IID remained high, indicating a new
behavioural mechanism was in place. Males first mated as T levels were declining. They were then challenged; then T increased,
and then IID increased again. Adult male T levels fluctuate, being low or declining in a socially stable environment and increasing
following a challenge, suggesting a regulatory or modulating role for T. The results are consistent with T having an endogenous
role: in the juvenile, driving behavioural change towards adulthood, and in adulthood, a modulating role regulating social
organisation. 相似文献
395.
In this paper, we present a three-step methodological framework, including location identification, bias modification, and out-of-sample validation, so as to promote human mobility analysis with social media data. More specifically, we propose ways of identifying personal activity-specific places and commuting patterns in Beijing, China, based on Weibo (China’s Twitter) check-in records, as well as modifying sample bias of check-in data with population synthesis technique. An independent citywide travel logistic survey is used as the benchmark for validating the results. Obvious differences are discerned from Weibo users’ and survey respondents’ activity-mobility patterns, while there is a large variation of population representativeness between data from the two sources. After bias modification, the similarity coefficient between commuting distance distributions of Weibo data and survey observations increases substantially from 23% to 63%. Synthetic data proves to be a satisfactory cost-effective alternative source of mobility information. The proposed framework can inform many applications related to human mobility, ranging from transportation, through urban planning to transport emission modeling. 相似文献
396.
We analyze the exploitation of an antibiotic in a market subject to open access on the part of antibiotic producers to the common pool of antibiotic efficacy. While the market equilibrium depends only on current levels of antibiotic efficacy and infection of the epidemiological system, the social optimum accounts for the dynamic externalities which relate those levels to the intertemporal use being made of the antibiotic. We show that depending on the parameters of the model, in particular the cost of production and the improvement in the recovery rate that results from antibiotic treatment, the positive steady-state level of antibiotic efficacy to which the system tends under open access can be lower or higher than the level which should prevail in the socially optimal steady state. In fact there are parameter configurations for which the steady states can be exactly the same. However, the paths leading to the steady state always differ. 相似文献
397.
Tuan T. Cao Kelly M. Hyland Alana Malechuk Lee A. Lewis Stanley S. Schneider 《Behavioral ecology and sociobiology》2009,63(4):521-529
Communication signals used in animal social interactions are frequently performed repetitively, but the function of this repetition
is often not well understood. We examined the effects of signal repetition by investigating the behavior of worker honey bees
that received differing numbers of vibration signals in established and newly founded colonies, which could use signal repetition
differently to help adjust task allocations to the labor demands associated with the different stages of colony development.
In both colony types, more than half of all monitored workers received more than one vibration signal, and approximately 12%
received ≥5 signals during a given 20-min observation period. Vibrated recipients exhibited greater activity and task performance
than same-age non-vibrated controls at all levels of signal activity. However, vibrated workers showed similar levels of task
performance, movement rates, cell inspection rates, and trophallactic exchanges regardless of the number of signals received.
Thus, the repeated performance of vibration signals on individual bees did not cause cumulative increases in the activity
of certain workers, but rather may have functioned to maintain relatively constant levels of activity and task performance
among groups of recipients. The established and newly founded colonies did not differ in the extent to which individual workers
received the different numbers of vibration signals or in the levels of activity stimulated by repeated signals. Previous
work has suggested that compared to established colonies, newly founded colonies have a greater number of vibrators that perform
signals on a greater proportion of the workers they contact. Taken in concert, these results suggest that vibration signal
repetition may help to adjust task allocations to the different stages of colony development by helping to maintain similar
levels of activity among a greater total number of recipients, rather than by eliciting cumulative effects that cause certain
recipients to work harder than others. 相似文献
398.
Dhruba Naug 《Behavioral ecology and sociobiology》2009,63(7):1023-1028
Social interactions are critical to the organization of worker activities in insect colonies and their consequent ecological
success. The structure of this interaction network is therefore crucial to our understanding of colony organization and functioning.
In this paper, I study the properties of the interaction network in the colonies of the social wasp Ropalidia marginata. I find that the network is characterized by a uniform connectivity among individuals with increasing heterogeneity as colonies
become larger. Important network parameters are found to be correlated with colony size and I investigate how this is reflected
in the organization of work in colonies of different sizes. Finally, I test the resilience of these interaction networks by
experimental removal of individuals from the colony and discuss the structural properties of the network that are related
to resilience in a social network.
This contribution is part of the special issue “Social Networks: new perspectives” (Guest Editors: J. Krause, D. Lusseau,
and R. James). 相似文献
399.
Patrick Gautier Marco Barroca Sophie Bertrand Cyril Eraud Maria Gaillard Michael Hamman Sébastien Motreuil Gabriele Sorci Bruno Faivre 《Behavioral ecology and sociobiology》2008,62(7):1159-1166
Several environmental factors have been shown to shape the pattern of investment of carotenoids into the expression of sexual
signals. Surprisingly, the impact of the social environment has been neglected. If a carotenoid-based sexual trait is used
by females to choose a mate or by males to assess the quality of potential competitors for mates, males, in the presence of
females, should upregulate expression of the trait. We tested this hypothesis in male zebra finches that were housed either
with females or in a male-only social environment. Additionally, to investigate whether the social modulation of the expression
of a sexual trait depends on the physiological need of carotenoids, we challenged half of the males with Escherichia coli lipopolysaccharide (LPS). We found that the social environment modulated the expression of bill color, with males kept in
the presence of females harboring a redder bill at the end of the 3 weeks that the experiment lasted. Males injected with
LPS showed duller bill color regardless of the presence of females, and social interactions with females result in upregulated
bill color similarly for phosphate-buffered saline (PBS) and LPS males. Thus, social environment and immune activation had
an additive effect on the expression of bill color. The effect of social environment on plasma carotenoids was less clear.
Indeed, a first replicate of the entire experiment showed that both immune challenge and social context affected bill color,
with a negative effect of immune challenge and a positive effect of the presence of females on circulating carotenoids. However,
a second replicate of the experiment showed only a negative effect of the immune challenge. These results, therefore, suggest
that the social environment can affect the expression of carotenoid-based sexual traits under both benign and carotenoid-demanding
conditions. Whatever the signaling function of bill color (female mate choice or male–male competition for mates), the observed
flexibility may be adaptive because the expression of the signal can be modulated depending on the expected rewards or costs
associated with the presence or absence of females. Nevertheless, the mechanisms underlying such an effect are still unknown. 相似文献
400.
Yutaka Saito Anthony R. Chittenden Kotaro Mori Katsura Ito Atsushi Yamauchi 《Behavioral ecology and sociobiology》2008,63(1):33-42
The number of nests containing egg masses a female makes over her lifetime and the pattern of scattering nests vary among
species in a genus of nest-weaving spider mites (Stigmaeopsis). We hypothesized that the scattered nests of small nest builders have a previously overlooked indirect effect in that the
void nests created after predation take on a new role as hindering devices that effectively decrease predator searching efficiency.
First, we demonstrated that the experimental design used in this study is a good reflection of the nest distribution pattern
of Stigmaeopsis takahashii (an intermediate-sized nest builder) in the field. Using this species as a model, we tested how different nest-scattering
patterns affect the predator to examine how scattering may indirectly provide an anti-predation strategy by increasing a predators
searching time. Next, we observed how artificially arranged void nests disturb predatory behavior in both starved and fully
fed predator females and showed that void nests have a strong hindering effect on predators. Thus, we concluded that the nesting
behavior of this mite species not only has anti-predator effects but must also have a stabilizing effect on predator–prey
interaction systems at the population level. 相似文献