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101.
Thomas R. Stewart Paulette Middleton Mary Downton Daniel Ely 《Journal of environmental psychology》1984,4(4):283-302
The use of photographs as surrogates for field observations is common in studies of perception and judgment of the visual environment despite theoretically important differences between photographs and three-dimensional scenes. The few available empirical studies of the validity of photographs as representations of the visual environment have methodological weaknesses. We describe a method for investigating the representativeness of photographs that differs from previous approaches in three important respects. First, individual subjects rather than group averages are analyzed. Second, multiple judgments are obtained so that the relations among judgments of photographs can be compared with the environment. Third, a ‘lens model equation’ analysis is used to examine relations among systematic components of variation in judgments. An illustrative study of visual air quality judgments is presented. It was found that, in the case of judgments of visual air quality, photographs provide a good representation of the visual environment. 相似文献
102.
Mapping the Conservation Landscape 总被引:12,自引:0,他引:12
103.
Thomas R. Stewart Paulette Middleton Daniel Ely 《Journal of environmental psychology》1983,3(2):129-145
A procedure based on judgments of human observers for measuring visual air quality in urban areas is described, and its reliability and validity are examined using the results of several studies conducted in a metropolitan area. It is concluded that the procedure provides a measure that is sufficiently reliable and valid to warrant its use in studies of the causes and consequences of changes in visual air quality. Substantial agreement was found among individuals with regard to judgments of visual air quality, but the possibility of differences between experienced and inexperienced observers requires further investigation. The paper provides an example of methods that can be used, and issues that should be addressed, in the development of perceived environmental quality indices. 相似文献
104.
Hypertrophic cardiomyopathy usually manifests clinically in the second or third decade of life. Two dimensional echocardiography is a reliable indicator of the presence of the disease. This technique is of use in the screening of fetuses at risk for familial cardiomyopathy. This report describes the prenatal echocardiographic detection of hypertrophic cardiomyopathy in the fetus of a mother with hypertrophic cardiomyopathy localized to the apical region of the left ventricle. 相似文献
105.
Two fetuses with extreme growth retardation (IUGR) of 31 and 34 weeks gestation were studied using a combination of two dimensional echocardiography (2DE), pulse wave Doppler (PWD) and differential measurement of the instantaneous vessel diameter techniques. The first fetus was diagnosed as having univentricular heart or possible double outlet right ventricle (DORV). Descending aorta blood flow was reduced as was indexing for weight. The second fetus was diagnosed as having univentricular heart with periodic bigeminal and trigeminal rhythm. Descending aorta blood flow was measured on two occasions and was reduced both times. Indexing for weight was within normal limits the first time and showed gross reduction on the second occasion prior to fetal demise. Fetal death occurred in both cases at 34 weeks gestation. Cardiovascular evaluation in fetuses with IUGR is useful as the detection of severe congenital cardiac abnormalities may substantially alter the management of these pregnancies, in particular caesarean section may be avoided when the prognosis for the fetus is considered hopeless. 相似文献
106.
T. Dooley L. D. Fairbanks H. A. Simmonds C. H. Rodeck K. H. Nicolaides P. W. Soothill P. Stewart G. Morgan R. J. Levinsky 《黑龙江环境通报》1987,7(8):561-565
Adenosine deaminase deficiency has been detected in the first trimester by direct analysis of enzyme activity in chorionic villi in a pregnancy at risk. Data for purine nucleoside phosphorylase activity in chorionic villi from healthy controls in the first trimester are also presented and should allow equally rapid diagnosis of this disorder. 相似文献
107.
Beth Clark Gavin B. Stewart Luca A. Panzone I. Kyriazakis Lynn J. Frewer 《Journal of Agricultural and Environmental Ethics》2016,29(3):455-478
Increased productivity may have negative impacts on farm animal welfare (FAW) in modern animal production systems. Efficiency gains in production are primarily thought to be due to the intensification of production, and this has been associated with an increased incidence of production diseases, which can negatively impact upon FAW. While there is a considerable body of research into consumer attitudes towards FAW, the extent to which this relates specifically to a reduction in production diseases in intensive systems, and whether the increased incidence of diseases represents a barrier to consumer acceptance of their increased use, requires further investigation. Therefore a systematic review of public attitudes towards FAW was conducted, with a specific focus on production diseases in intensive systems. Four databases were searched to identify relevant studies. A screening process, using a set of pre-determined inclusion criteria, identified 80 studies, with the strength of evidence and uncertainty assessed for each. A thematic analysis led to the identification of 6 overarching themes constructed from 15 subthemes. The results demonstrate that the public are concerned about FAW in modern production systems. Concern varied in relation to age, gender, education and familiarity with farming. Naturalness and humane treatment were central to what was considered good welfare. An evidence gap was highlighted in relation to attitudes towards specific production diseases, with no studies specifically addressing this. However, the prophylactic use of antibiotics was identified as a concern. A number of dissonance strategies were adopted by consumers to enable guilt free meat consumption. 相似文献
108.
Charles C. Morris Paul M. Stewart Thomas P. Simon 《Journal of the American Water Resources Association》2007,43(2):295-307
Abstract: This study evaluated biological integrity expectations of fish assemblages in wadeable streams for the Alabama portion of the Choctawhatchee River watershed using a multimetric approach. Thirty‐four randomly selected stream sites were sampled in late spring 2001 to calibrate an index of biotic integrity (IBI). Validation data were collected during the spring 2001, and summer and fall of 2003 from disturbed and least‐impacted targeted sites (n = 20). Thirty‐five candidate metrics were evaluated for their responsiveness to environmental degradation. Twelve metrics were selected to evaluate wadeable streams and four replacement metrics were selected for headwater streams. Scores that ranged from 58 to 60 were considered to be representative of excellent biotic integrity (none found in this study), scores of 48‐52 as good integrity (31% of the sites in this study), 40‐44 as fair (43%), 28‐34 as poor (21%), and 12‐22 as very poor (5%). Of the four stream condition categories (urban, cattle, row crop, and least impacted), the IBI scores for urban and cattle sites differed significantly from least‐impacted sites. Row crop sites, although not significantly different from least‐impacted, tended to have greater variability than the other categories. Lower IBI scores at both urban and cattle sites suggest that the IBI accurately reflects stream impairment in the Choctawhatchee River drainage. 相似文献
109.
Attitudes towards Recycling Household Waste in Exeter, Devon: quantitative and qualitative approaches 总被引:5,自引:0,他引:5
Recycling of household waste has become a very problematic area of British local government policy-making in which central government has set ambitious targets. Although local government can provide facilities for recycling, the attitudes of residents will be crucial if these targets are to be met. Accordingly, this paper outlines a framework for studying how households decide to recycle or not. The framework has been tested in Exeter in south-west England where a major survey found that respondents were much more likely to recycle if they had access to a structured kerbside recycling scheme. Many other factors influenced their attitudes and behaviours towards recycling, including their acceptance of the activity and their perception of the benefits and problems of recycling as a whole. The research uses the quantitative and qualitative data from the survey to demonstrate how individual attitudes can impact on recycling and how such research can yield useful data to enable policy-makers to adapt measures accordingly. 相似文献
110.
Floodplain forests are flood-dependent ecosystems. They rely on well-timed, periodic floods for the provision of regeneration sites and on tapered flood recession curves for the successful establishment of seedlings. These overbank flood events are described as regeneration flows. Once floodplain forest trees are established, in order to grow they also require adequate, although variable, river stage levels or maintenance flows throughout the year. Regeneration flows are often synonymous with flood flows and only occur periodically. There is a disparity between this need for varied interannual flows over the decadal time frame and the usual annual cycle of flow management currently used by most river management agencies. Maintenance flows are often closer to established minimum flows and much easier to provide by current operational practices.A number of environmental flow methodologies, developed in North America, Australia, and South Africa are described in this review. They include the needs of the floodplain environment in the management and allocation of river flows. In North America, these methodologies have been put into practice in a number of river basins specifically to restore floodplain forest ecosystems. In Australia and South Africa, a series of related holistic approaches have been developed that include the needs of floodplain ecosystems as well as in-channel ecosystems. In most European countries, restoration of floodplain forests takes place at a few localized restoration sites, more often as part of a flood-defense scheme and usually not coordinated with flow allocation decisions throughout the river basin. The potential to apply existing environmental flow methodologies to the management of European floodplain forests is discussed. 相似文献