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391.
ABSTRACT: Two scenarios of CO2-induced climatic change are used to estimate changes in water use for a number of municipalities in the Great Lakes region of Canada and the United States. Both scenarios, based on General Circulation Models produced by the Goddard Institute for Space Studies (GISS) and Geophysical Fluid Dynamics Lab (GFDL), project warmer temperatures for the region. Using regression models based on monthly potential evapotranspiration for individual cities, it is projected that annual per capita water use will increase by a small amount, which will probably have only a marginal effect on water supplies in the Great Lakes basin. This method could also be used to assess the potential impacts of CO2-induced climatic change on water use by the agriculture and power sectors, as well as the effectiveness of water policy initiatives, such as price changes. More work is needed to project water use during peak periods (warm dry spells), which may occur more frequently in a 2 × CO2 climate in this region.  相似文献   
392.
ABSTRACT: Areas of low topographic relief have low water-table gradients and make the direction of movement of contaminants from land fills in the ground water difficult to predict from regional gradients alone. The landfill, nearby free-flowing ditches or canals, variations in hydraulic conductivity, and the influence of nearby pumping wells can all affect the direction of flow. In low-gradient areas the concepts of “upgradient” and “downgradient” are less useful in planning the location of monitoring wells than in areas of higher relief. Low-relief areas also may be affected by the discharge of mineralized water from deeper aquifers, naturally or through irrigation, which can mask geochemical surveys intended to detect landfill leachate. Examples of effects of low topographic relief are noted in southeast Florida where water-table gradients are 7×10?-4 to 5×10?-4 feet per foot. Water-table mounding beneath the landfill and the drainage effects of nearby ditches and well have created multiple leachate plumes in Stuart where one plume migrated in a direction opposite to the apparent regional gradient. In Coral Springs analysis suggests a bifurcating plume migrating along two narrow zones. In Fort Pierce it was difficult to detect leachate because of mineralized irrigation water and fertilizer runoff from an adjacent citrus grove.  相似文献   
393.
Ranunculus spp. are the dominant plants of lowland chalk stream habitats in England. The spatial variability of sediment characteristics (silt–clay, organic matter, total phosphorus and total nitrogen content) within stands of Ranunculus spp. was investigated in 12 rivers in lowland England. Variability was found to be high and there were no discernible differences between samples taken from within Ranunculus and a limited number of samples from bare substrate. For two of these rivers, comparisons were also made between reaches upstream and downstream of waste water treatment works outfalls in terms of the characteristics of the sediments within Ranunculus stands. In one river a clear increase in sediment nutrient, fine and organic material content was observed downstream but in the other there was no consistent difference. Temporal variability was considered for two rivers in the Frome catchment, Dorset, by analysing the monthly variability in sediment organic matter and silt–clay content beneath Ranunculus stands over an annual cycle of growth and die-back. Whilst a clear pattern of fine and organic material retention consistent with seasonal plant growth patterns was evident at one site, the three sites displayed different temporal patterns. This inconsistency is believed to reflect differences in sediment supply at the three sites.  相似文献   
394.
A longitudinal predictive design was used to test a model linking changes in structural and psychological empowerment to changes in job satisfaction. Structural equation modeling analyses revealed a good fit of the data from 185 randomly selected staff nurses to the hypothesized model. Changes in perceived structural empowerment had direct effects on changes in psychological empowerment and job satisfaction. Changes in psychological empowerment did not explain additional variance in job satisfaction beyond that explained by structural empowerment. The results suggest that fostering environments that enhance perceptions of empowerment can have enduring positive effects on employees. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
395.
Based on data obtained from three samples of participants from both a work organization and a college setting, this paper addressed two major research objectives relevant to organizational behavior and applied psychology. First, we wanted to explore the nature of implicit theory of skill malleability in more detail than has been done before. This was done by drawing on KSAO dimensions from the task/job analysis literature, and examining linkages among: (a) task/job analysis; (b) implicit theories; and (c) competency modelling (an area in which there has been little empirical research). The studies found multiple factors of beliefs about KSAO improvability and showed a clear ordering of improvability beliefs (from most to least improvable) that follow predictions made in the Iceberg model of competencies. The present studies also found relationships between perceptions of KSAO importance and KSAO improvability, as well as evidence that this relationship is stronger for people who have been in a role/job longer, having had greater opportunity to observe critical KSAOs improve over time. A second major objective of the research was to explore improvability beliefs within a nomological network that would help to further establish the construct validity of the beliefs within the learning/development area. Using structural modelling, the improvability beliefs were tied to learning‐oriented concepts including self‐efficacy for learning and development, tendency to compare oneself to others when learning, as well as learning‐oriented attitudes and behaviors. The potential practical value of improvability beliefs is discussed, as are suggestions for future research. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
396.
Book reviews     
“Water Planning and the Regions”

Edited by P. J. Purdy, R. S. A.

Discussion Paper No. 9, 1977, £1.50.

Tenant participation in council housing management; Housing Development.

Directorate Occasional Paper 2/77, DoE London, 1977.

Getting tenants involved: a handbook on systems of tenant participation in housing management; DoE London, 1977.

La politica dei servizi tra razionalizzazione e rinnovamento

Alberto L'Abate (1978)

Marsilio Editori, Padova, pp. 316

Handbook for Environmental Planning: the social consequences of environmental change.

J. McEnvoy & T. Dietz (1977)

New York, J. Wiley, pp. 323. Price £15.50

Planning and Urbanism in China

Progress in Planning Vol. 8, Part 2, Fo. 1 N. Jeffrey and M. Caldwell, pp. 97–182, 1977

Pergamen, £4.00

The European Community's Regional Fund

Ross B. Talbot

Progress in Planning, Vol. 8, Part 3, pp. 183–281

Pergamon Press, 1977

Providing the Posh Words

W. Hampton, DoE

1978. £1.50. 60pp.

Four Titles on Conservation

A Critical Bibliography of Building Conservation. John F. Smith. Mansell, London 1978. 207 pages including index. Hard back, £12.90.

Conservation and Planning. Alan Doby. Hutchinson — The Built Environment. 1978. 173 pages. Some illustrations. Paper back, £3.25.

A Study in Conservation. Winston Barnett and Cyril Winskell. Oriel Press, 1977. 45 pages, in English, French and German. Illustrated. Paper back, £3.75.

Interpreting the Conserved Environment. Working Paper No. 29. Brian Goodey. Oxford Polytechnic Department of Town and Country Planning, 1977. 65 pages. Paper back, not priced.

“Belgium”, R. Riley, £3.25, 205 pp.

“The Netherlands”, D. Pinder, £3.25, 194 pp.

“The USSR”, J. C. Dewdney, £3.25, 262 pp.

Development Strategy of Bangladesh

Nurul Islam

Oxford, Pergamon Press, 1978, 109 pp.  相似文献   

397.
An extracellular fraction from the lignin degrading white-rot fungus, Coriolus versicolor, can biosolubilize leonardite and pretreated lignites in vitro. Leonardite is often found as an overburden to lignite deposits, and is related to humic acid, and is more oxidized than lignites. Extracts from certain fungi such as C. versicolor solubilize leonardite. The biosolubilization activity is at least in part enzymatic in nature. A protein which is at least partly responsible for the solubilization effect has been substantially purified and concentrated by ultrafiltration and ion-exchange chromatography from the broth of an agitated submerged culture of C. versicolor grown in a defined medium. An in vitro coal biosolubilization assay was used to establish the effects of various physical and chemical factors affecting enzyme activity, including temperature and the salt and buffer composition of the reaction mixture. Some initial studies on the mechanism of the enzymatic leonardite biosolubilization reaction are described.  相似文献   
398.
ABSTRACT: Nine surface water‐quality variables were analyzed for trend at 180 Virginia locations over the 1978 to 1995 period. Median values and seasonal Kendall's tau, a trend indicator statistic, were generated for dissolved oxygen saturation (DO), biochemical oxygen demand (BOD), pH (PH), total residue (TR), nonfilterable residue (NFR), nitrate‐nitrite nitrogen (NN), total Kjeldahl nitrogen (TKN), total phosphorus (TP), and fecal coliform (FC) at each location. Each location was assigned to one of four physiographic regions, and mean state and regional medians and taus were calculated. Widespread BOD and NFR improvements were detected and FC improvements occurred in the state's western regions. TR and TKN exhibited predominantly increasing trends at locations throughout the state. BOD, TKN, NFR, and TR medians were higher at coastal locations than in other regions. NN, TKN, and TR exhibited predominantly increasing trends in regions with high median concentrations, while declining trends predominated in regions with relatively high BOD, FC, and NFR medians. Appalachian locations exhibited the greatest regional water‐quality improvements for BOD, FC, NFR, and TKN. Factors responsible for regional differences appear to include geology, land use, and landscape features; these factors vary regionally.  相似文献   
399.
Otolith increment age estimates for a deepwater species, Allocyttus verrucosus, were validated by comparison with the results from 210Pb:226Ra radiometric analysis. Transverse sectioning and subsequent grinding of otoliths to a thickness of 0.2 mm revealed increments which provided age estimates for a range of fish sizes. Age estimates ranged from 7 yr for an immature fish of 15.2 cm total length (TL) to 130 yr for a female fish of 36.5 cm TL. Age at maturity was estimated as 28 yr for females and 24 yr for males. In comparison, radiometric analysis of whole otoliths, using a single linear otolith-mass growth-rate model suggested maximum ages of 130 to 170 yr for fish of 34 to 35 cm TL. Radiometric ages were also recalculated using a two-phase otolith-mass growth-rate model in which the growth rate was assumed to slow after maturity to 90% of the pre-maturity rate. This reduced the maximum age to 132±15 yr for a mean fish length of 34.5 cm. Age at maturity for females was estimated at 34 yr. The similarity between age estimates from otolith-increment counts and radiometric analysis strongly supports the accuracy of results from both methods, and encourages further use of such comparisons as an alternative to traditional validation techniques.  相似文献   
400.
This study tested a relational demography model of workgroup identification. We theorized that early in workgroup formation, (a) racial identification would moderate the influence of racial dissimilarity on member communication behavior (frequency and length of verbal participation) during a group task, (b) member communication behaviors would mediate the effect of racial dissimilarity on workgroup identification, and that (c) these effects would be affected non‐symmetrically by racial group membership (White, Black). This model was tested among a sample of 211 undergraduates (113 White and 98 Black), working in 43 temporary workgroups. Whites' racial identification moderated the relationship between racial dissimilarity and member communication behaviors, which in turn partially mediated the effect of racial dissimilarity on workgroup identification, generally consistent with our model. Among Black workgroup members support for our model was limited. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
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