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461.
Infosafe today is a MSDS Management system utilised by many of the world lead ing companies, locally, nationally or globally. The success of Infosafe lies in the system design, which was conceived 相似文献
462.
Khalid Karim Maureen E. Gubbels Ian C. Goulter 《Journal of the American Water Resources Association》1995,31(6):1063-1077
ABSTRACT: A critical examination of the techniques used to assess and specify environmental instream flow requirements is provided. The strengths and weaknesses of individual techniques are evaluated on both an absolute and a comparative basis. Particular attention is given to the problem of specifying environmental flow requirements in Australia where the hydrology has distinctly different characteristics to those in countries where most of the models for prediction of instream flow requirements were developed. Broad recommendations as to the suitability and use of the different techniques for different conditions are provided. 相似文献
463.
Ian R. Gellatly 《组织行为杂志》1995,16(5):469-485
This study examined whether an employee's level of absenteeism was affected by age, organizational tenure, perceptions of interactional justice, affective and continuance commitment, and the perceived absence norm in the employees' work unit or department. One hundred and sixty-six nursing and food services employees in a mid-size chronic care hospital provided attitudinal and perceptual data on an employee survey. Absence data (absence frequency and total days absent) were collected during the 12-month period immediately following an employee survey. Hypothesized relations between the various individual- and group-level factors and employee absenteeism were specified in a structural model and tested using LISREL 7 (Joreskog and Sorbom, 1989). General support was found for the study hypotheses. 相似文献
464.
Against a background of inward investment into the region, the paper examines crucial issues relating to labour. It examines approaches to recruitment and the selection process. Skill shortages and strategies for overcoming the problem are analysed together with a consideration about management and managers. The paper concludes with a detailed assessment of policies relating to training. 相似文献
465.
J. J. McDonnell Ian F Owens M. K. Stewart 《Journal of the American Water Resources Association》1991,27(4):679-685
ABSTRACT: Soil water potentials, slope throughflow, runoff chemistry, and isotopic composition were monitored in a 97 m2 zero-order basin within the Maimai 8 watershed on the South Island of New Zealand, for a natural rain storm and two artificial water applications. Contrary to results previously reported for other portions of the Maimai catchment, much of the runoff occurred as a shallow subsurface organic layer flow. For the 47 mm natural rain event, pre-storm soil matric potential ranged from ?60 to ?150 cm H2O. No saturation was produced within the profile, and the majority of storm runoff emanated from flow within the organic horizon perched on the mineral soil surface. Hillslope applications corroborated this interpretation by showing >90 percent new water flushing with negligible mineral soil moisture response. Although the mechanisms cited in the text are not representative of the entire catchment, the study demonstrates: (1) the value of a combined physical-chemical-isotopic approach in quantifying slope processes, and (2) the heterogeneous nature and diversity of slope runoff pathways in a relatively homogeneous catchment. 相似文献
466.
Ian D. Moore 《Journal of the American Water Resources Association》1983,19(6):961-965
ABSTRACT: Precipitation, throughfall, and stream pH were measured weekly over a 27-week period in 1982 on the Little Millseat watershed in eastern Kentucky. The average pH values over the study period were 4.3, 4.9, and 6.4, respectively, indicating significant buffering as water moved from the atmosphere, through the deciduous canopy, and through or over the soil to the stream. Regression analysis demonstrated that the timing and amount of precipitation were important factors influencing the pH of the throughfall. Weekly precipitation and the three-week average precipitation were statistically significant variables, explaining 53 percent of the variance in the observed through- fall pH. Precipitation pH was not a statistically significant variable for this watershed and sampling period. 相似文献
467.
Ian G. Wallis 《Journal of the American Water Resources Association》1978,14(3):576-586
ABSTRACT: An experimental investigation of the random component in stream meandering is described. The results of sixty replicate experiments of meander initiation and development made using the same discharge, bed material and bed slope are described and analyzed. It is demonstrated that the commencement of meandering is a random process. The random component in meander behavior is indicated by the size of the coefficients of variation of meander amplitude and wavelength of 0.45 and 0.22, respectively. A simple model is put forward to explain the observed deterministic and random components of meander behavior. 相似文献
468.
Ian C. Laurie 《Journal of Environmental Planning and Management》1985,28(2):86-91
The country estate has a particular place in the English countryside and its contribution to the landscape scene is distinct and valuable. The paper describes an approach to planning a large country estate of parkland, woodland and estate villages in Cheshire. A Reconnaissance Survey led to the Outline Strategy for six ‘landscape types’ discovered on the estate. The Landscape Conservation Plan is described and the crucial importance of conservation measures is emphasised. 相似文献
469.
Ian B. MacNeilt 《Journal of the American Water Resources Association》1985,21(5):785-796
To accommodate possible parameter changes in time series at times which are not specified in advance, we propose an adaptive procedure for estimating parameters and for forecasting. The mechanism for activating the adaptive procedure is a successively updated change-detection statistic. The statistic has small expected value when no change is present and has large value when change takes place - the larger the change, the larger the statistic. The statistic defines discounting factors which determine how much of the past will be used both for estimating parameters and for forecasting. The change-detection statistic is designed to effect major changes to parameter estimates and to forecasts in a discrete fashion only, as opposed to certain other adaptive procedures that react continuously to perceived fluctuations in data, and so indicate change even when parameters remain fixed. The procedure is illustrated using exponential smoothing and Holt's linear exponential smoothing and is applied to a hydrological series. 相似文献
470.
Ian Traquair Ball 《Journal of the American Water Resources Association》1973,9(3):529-537
ABSTRACT Methods of institutional coordination derived from the applied behavioral sciences have been useful in determining the policy planning, and implementation responsibilities that must be shared between local governments, watershed districts, and a regional planning body in the Minneapolis-St. Paul Metropolitan Area. The confines of the traditional behavioral science models of organizations and institutional change processes, and the realities of administrative systems imbedded in political processes at both the local and state levels, have created conflicts between regional planners, watershed district staff and consultants, and municipal administrators. A conceptual framework based on work by Selznick on institutions was applied to two watershed districts, and the results evaluated for other research purposes as well as policy development for the 1973 Minnesota legislative session. 相似文献