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Jonathan M. Gallimore Barbara B. Brown Carol M. Werner 《Journal of environmental psychology》2011,31(2):184-191
We assessed environmental and perceptual correlates of walking and walkability for fifth graders from three communities attending two schools: A new urban/LEED-ND pilot community, mixed, and standard suburban community. Irvine-Minnesota Inventory (IMI) walkability audits showed that new urban blocks provided more traffic safety, pleasurability, crime safety, density, and diversity. New urban routes offered greater traffic safety, accessibility, pleasurability, crime safety, and diversity, but suburban routes had greater housing density, net of controls (parental education, rooms in the home, home ownership, parent preference for child to walk to school). Parents and children perceived new urban routes to be more walkable and children walked more when they lived on more walkable routes. The suburban hierarchical street design exposed children to varied traffic safety conditions by funneling their walks from cul-de-sacs to arterials. The new urban routes to a centrally located school passed by pleasant open spaces, suggesting how community organization can create better walking conditions. 相似文献
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Using the concept of ontological security, this paper examines the physical and psychological loss of home and community following Hurricane Katrina. This qualitative longitudinal study includes 40 heads of households with school‐age children who lived in New Orleans during Hurricane Katrina. Participants describe a breakdown in their social fabric at the individual and structural/community levels that contributes to a sense of community loss and social displacement, disrupting their ontological security—their notion of safety, routine and trust in a stable environment. Three interrelated reactions were common: 1) experiencing nostalgia for their old neighbourhoods specifically and New Orleans in general; 2) experiencing a sense of loss of people and things that represented a level of security or constancy; 3) initiation of a process for re‐establishing ontological security whether or not they returned to New Orleans. The paper concludes that intangible losses have an important psychological effect on community redevelopment and recovery from trauma. 相似文献
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An Erratum has been published for this article in Journal of Organizational Behavior 26(7) 2005, 873. Previous research on the relationship between alternative employment opportunities and cooperation has neglected the distinction between evaluations and restrictions. Thus, one cannot analyze the relationship between attractiveness of alternative employment opportunities and organizational citizenship behaviors (OCB) under different levels of perceived ease of finding alternative employment. In a pilot study with N = 149 German employees, we confirm the proposed distinction with confirmatory factor analyses. Based on power‐dependence theory and rational choice models, we predict that under high ease the relationship between attractiveness and OCB should be more strongly negative than under conditions of low ease. In addition, we hypothesize that the interaction between attractiveness and ease should be greater for OCB than for task performance because task performance is exchanged in a relationship with an enforceable, binding contract, while OCB is voluntarily. Results from moderated multiple regression analysis on N = 86 German professional–supervisor dyads support our prediction for a negative relationship between attractiveness and OCB under high ease. Under low ease, we find a positive relationship between attractiveness and OCB. Moreover, there was no relationship with the interaction and task performance. Implications of the findings both for extra‐role and job mobility theory formation and research are discussed. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
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Alexander Lukeneder Mathias Harzhauser Stefan Müllegger Werner E. Piller 《Marine Biology》2008,154(1):175-182
Stable isotopes (δ18O and δ13C) were measured in successive chambers of the aragonitic shells of the small deep-sea squid Spirula spirula (Linnaeus 1758) (class Cephalopoda, subclass Coleoidea, order Sepioidea, family Spirulidae) to determine whether their depth distributions
change with age. The spiral shells, ranging in diameter from 18 to 23 mm (30–38 chambers), were collected between 2000 and
2006 from beaches in six widely separated locations in three oceans, the Atlantic (Tobago and Canary Islands), Indian (Madagascar,
Maldives, and Perth, Australia), and Pacific Oceans (Ulladulla, Australia). The patterns for both isotopes were highly correlated
in specimens from all six sites. The δ18O data suggest that after hatching at depths >1,000 m at temperatures of 4–6°C, the squid migrate into shallower, warmer waters
at 12–14°C at depths of 400–600 m. Subsequently, the increasing δ18O values suggest a migration back into somewhat cooler, deeper habitats. The δ13C values also revealed three ontogenetic stages in all six specimens, including a major shift from positive to negative values,
which probably corresponds to sexual maturation, the initiation of reproduction, and concomitant changes in diet. In three
of the six specimens (from Tobago, Canary Islands, and Maldives) a fourth embryonic stage (not detected in the oxygen data)
was accompanied by markedly less positive δ13C values in the first few chambers. These data, combined with the scanty life history information from previous studies of
S. spirula, can be used to compare the habitat requirements of related extant and fossil cephalopod genera.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
500.
Indirect effects propagated through intervening species in a food web have important effects on community properties. Traditionally, these indirect effects have been conceptualized as mediated through density changes of the intervening species, but it is becoming increasingly apparent that those mediated through trait (phenotypic) responses also can be very important. Because density- and trait-mediated indirect effects have different properties, it is critical that we understand the mechanisms of transmission in order to predict how they will interact, and when or where they will be important. In this study, we examined the mechanisms and consequences of the lethal (density-mediated) and nonlethal (trait-mediated) effects of a larval odonate predator on a guild of four herbivore species (a larval anuran and three species of snails) and their resources. We also manipulated system productivity in order to explore the effects of environmental context on the transmission of these two types of indirect effects. We show that trait-mediated effects arising from the predator can be very strong relative to density-mediated effects on both the competing herbivores and the species composition and production of their resources. A number of these indirect effects are shown to be contingent on productivity of the system. We further present evidence that trait- and density-mediated indirect effects originating from a predator may be transmitted independently through different routes in a food web, particularly when spatial responses of the transmitting prey are involved. Finally, effects on prey growth due to trait responses to the predator varied from negative to positive in predictable ways as a function of time and indirect effects on the larger food web. These results indicate the important role that trait-mediated indirect effects can play in trophic cascades and keystone predator interactions, and we discuss how the mechanisms involved can be incorporated in theory. 相似文献