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241.
ABSTRACT: In the last decade, watershed groups (WG) established through government initiatives have become an important part of the natural resource management landscape in developed economies. In this paper, the authors reflect upon their research and experience with Landcare in Victoria, and to a lesser extent with Watershed Councils in Oregon, to identify the principles that appear fundamental to sustaining effective WG. In the first instance, these groups must be established at a local scale using social as well as biophysical boundaries. It is also critical that WG are embedded within a supportive institutional framework that identifies realistic roles for private landowners, local organizations such as WG, and regional planning bodies. Without broad stakeholder representation, the perceived benefits of participation are quickly forfeited. It is simply unrealistic to expect an effective network of WG to be sustained without substantial investment by government to provide for program management, group coordination, and cost sharing for on‐ground work. There must also be the commitment and skills within a program to establish processes that build trust and competency amongst citizens and agencies. These principles should also provide a foundation for the critical evaluation of WG programs.  相似文献   
242.
Previous research has found that employed mothers experience conflict between the roles of mother and employee, and that interrole conflict is negatively correlated with marital adjustment. Furthermore, research has shown that social support and personality hardiness moderate the interrole conflict/marital adjustment relationship. However, a longitudinal assessment of the effect of interrole conflict on marital adjustment has not been conducted, nor has the moderating role of social support and hardiness been considered within the same analysis. To address these two issues, the interrole conflict, family support, personality hardiness and marital adjustment of 51 employed mothers were assessed twice, three months apart. Using hierarchical regression analyses, interrole conflict and family support exerted main effects on marital adjustment at time 1, More importantly, a significant interrole conflict/family support interaction predicted change in marital adjustment over three months. High family support exerted a negative impact on marital adjustment when interrole conflict was high. The alternative hypothesis that initial levels of marital adjustment predict change in interrole conflict was tested but not supported.  相似文献   
243.
The literature available on organizational psychology has largely neglected the issue of industrial conflict, and little is known about individual psychological effects of industrial conflict such as labour disputes and strikes. Psychological consequences of involvement in a strike were assessed in this research. Data were collected from 117 full-time, white collar union members immediately following a 22 day strike, and again two and six months later. Negatively perceived industrial relations events (e.g. 'strike or lockout', 'being involved in negotiations') were associated with marital adjustment, psychosomatic symptoms and a lack of psychological well-being on completion of the strike, and predicted unfavourable changes in psychological well-being over the next two and six months. A framework for understanding the negative effects of labour disputes and strikes is proposed, and the role of the organizational psychologist when such conflicts occur is considered.  相似文献   
244.
In this paper a compartment model of the highly vulnerable Arctic terrestrial food chain "lichen-reindeer-man" is outlined. Based upon an analysis of measured (137)Cs and (90)Sr contents in lichen and reindeer meat from 1961 up to 2001, site specific model parameters for two regions in north-western Arctic Russia and for Kautokeino municipality in Arctic Norway have been determined. The dynamics of radionuclide activity concentrations in the "lichen-reindeer-man" food chain for all areas was satisfactorily described by a double exponential function with short-term and long-term effective ecological half-lives between 1-2 and 10-12 years, respectively, for both (137)Cs and (90)Sr. Using parameter values derived from the model, life-time internal effective doses due to consumption of reindeer meat by reindeer-breeders after an assumed single pulse deposit of 1 kBq m(-2) of (137)Cs were estimated to be 11.4 mSv (Kola Peninsula), 5 mSv (Nenets Autonomous Area), and 2 mSv (Kautokeino, Norway). Differences in vulnerability to radiocaesium deposition were due to differences in transfer between lichen and reindeer and in diet between the three regions.  相似文献   
245.
Cronbach's alpha is one of the most widely used measures of reliability in the social and organizational sciences. Current practice is to report the sample value of Cronbach's alpha reliability, but a confidence interval for the population reliability value also should be reported. The traditional confidence interval for the population value of Cronbach's alpha makes an unnecessarily restrictive assumption that the multiple measurements have equal variances and equal covariances. We propose a confidence interval that does not require equal variances or equal covariances. The results of a simulation study demonstrated that the proposed method performed better than alternative methods. We also present some sample size formulas that approximate the sample size requirements for desired power or desired confidence interval precision. R functions are provided that can be used to implement the proposed confidence interval and sample size methods. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
246.
Joining a new organization to change jobs is an influential event in an employee's career. Thus, inter-organizational job changes have sparked growing scholarly interest, especially in the temporal dynamics involved in detaching from organizations and adapting to new ones. While it is widely accepted that employees adapt differently to job changes, the influence of employees' career orientations on changes in job attitudes has not yet been considered. This is surprising given that a key difference between self-centered and organization-centered career orientations is a positive attitude toward job changes. Building on hedonic adaptation, we examined how career orientations influence changes in job satisfaction and turnover intention throughout a job change. We compared self-centered and organization-centered employees using random coefficient modeling on two longitudinal data sets with voluntary job changers. Our results illustrate that self-centered career orientations foster a stronger decline in job satisfaction with the new employer, as well as a larger increase in turnover intention, than organization-centered career orientations. In contrast, employees with organization-centered career orientations experienced an upward trend in job satisfaction toward the end of the first year. Our findings offer important implications for research on the determinants of job attitude trajectories when individuals join a new organization.  相似文献   
247.
This research examined relationships between alternative measures of affect and supervisory performance ratings. The first study showed that dispositional rather than state affect significantly predicted supervisory ratings of performance over time. Since the measures of affect differed on both content and temporal dimensions, a follow‐up study was conducted to explicate the results. The second study found that a pleasantness‐based measure of dispositional affect (Berkman, 1971a) again predicted rated performance over time, but activation‐based measures of both dispositional and state affect (using PANAS scales) were not predictive of supervisory evaluations of performance. The implications of these findings in terms of research on affect and the longstanding pursuit of the happy–productive worker are discussed. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
248.
We assessed the relationship between the quality (i.e., job characteristics, role stressors, and interpersonal relationships) and quantity of part-time employment, and work-related attitudes and aspirations among 349 students. Neither the linear nor the quadratic components of employment quantity predicted any of the outcome variables. Motivation to do good work was predicted both by role stressors and by family achievement orientation. Career maturity was predicted by role stressors at work, and cynicism by role stressors and satisfaction with interpersonal relationships. In contrast, job involvement was significantly related to family achievement orientation but not to any perceived job factors. These findings question the assumption that only intensive work during high school exerts negative effects for teenagers, and support the importance of employment quality for teenagers as well as adults. © 1998 John Wiley & Sons, Ltd.  相似文献   
249.
An issue in the design of combined sewer overflow storage tunnels is to avoid “geysering” which is an air/water mixture blowing up through vertical shafts connected to the tunnel. Studies indicate that the origin of this phenomenon is the entrapment of large air pockets as the rapidly filling tunnel undergoes a transition between free surface and pressurized flow. Commonly implemented numerical models are of the shock fitting type that tracks the location of a pipe filling bore. However, the flow regime transition does not have to occur through a pipe filling bore. Another possibility involves a free surface bore with a following gradual transition to a full pipe condition. Large air volumes may be trapped in this situation following the bore reflection off a tunnel transition if this reflection closes the flow cross-section. Experimental observations are presented to demonstrate both types of flow regime transition. Traditional shock fitting methods are ill-equipped to accurately simulate gradual flow regime transitions. The shock capturing method proposed by Vasconcelos et al. (J Hydraul Eng 132(6):553–562, 2006) is demonstrated to be capable of resolving both types of observed bores.  相似文献   
250.
Lau JA  McCall AC  Davies KF  McKay JK  Wright JW 《Ecology》2008,89(3):754-762
Biotic interactions, such as competition and herbivory, can limit plant species ranges to a subset of edaphically suitable habitats, termed the realized niche. Here we explored the role that herbivores play in restricting the niche of serpentine ecotypes of the native California annual Collinsia sparsiflora. We planted seeds from four populations into a range of natural field environments that varied in the presence/absence of naturally occurring C. sparsiflora and in predicted suitability for growth and survival of the serpentine ecotype of C. sparsiflora. Path analysis was then used to model the direct and herbivore-mediated indirect effects of environmental variables on the survival of C. sparsiflora serpentine ecotypes. We found that C. sparsiflora received more herbivory when planted into areas where serpentine ecotypes of C. sparsiflora were not predicted to persist, and that increased herbivory was associated with decreased survival, suggesting that herbivores may limit the distribution of C. sparsiflora serpentine ecotypes. Additionally, we demonstrated that edaphic environmental variables impacted the survival of C. sparsiflora serpentine ecotypes both directly and indirectly, by altering interactions with herbivores. These indirect effects were probably trait-mediated and probably occurred because edaphic factors may influence plant traits that, in turn, alter attractiveness to herbivores. Although the magnitude of direct effects exceeded the magnitude of indirect effects, many strong herbivore-mediated indirect effects were detected. Thus, interactions between the abiotic environment and insect herbivory contributed to restricting the niche of C. sparsiflora serpentine ecotypes to a subset of available habitat.  相似文献   
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