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871.
本文用案例阐述了现代整体橱柜内微环境中的甲醛污染,导致了对人体健康的危害。并用体积相同而材料不同的橱柜进行柜内空气中甲醛的检测比对和柜内微环境中甲醛污染的调味品检测比对。 相似文献
872.
L. Star E. D. Ellen K. Uitdehaag F. W. A. Brom 《Journal of Agricultural and Environmental Ethics》2008,21(2):109-125
The combination of breeding for increased production and the intensification of housing conditions have resulted in increased
occurrence of behavioral, physiological, and immunological disorders. These disorders affect health and welfare of production
animals negatively. For future livestock systems, it is important to consider how to manage and breed production animals.
In this paper, we will focus on selective breeding of laying hens. Selective breeding should not only be defined in terms
of production, but should also include traits related to animal health and welfare. For this we like to introduce the concept
of robustness. The concept of robustness includes individual traits of an animal that are relevant for health and welfare.
Improving robustness by selective breeding will increase (or restore) the ability of animals to interact successfully with
the environment and thereby to make them more able to adapt to an appropriate husbandry system. Application of robustness
into a breeding goal will result in animals with improved health and welfare without affecting their integrity. Therefore,
in order to be ethically acceptable, selective breeding in animal production should accept robustness as a breeding goal.
L. Star, E. D. Ellen contributed equally to this work. Star belongs to the Adaptation Physiology Group, Wageningen University,
and the rest of the authors belong to the Animal Breeding and Genomics Centre, Wageningen University. 相似文献
873.
《Disasters》2001,25(2):181-183
Books reviewed:
Rutherford H., Platt et al. Disasters and Democracy: The Politics of Extreme Natural Events
S., Suri Orissa Disaster: Agony of the Living 相似文献
Rutherford H., Platt et al. Disasters and Democracy: The Politics of Extreme Natural Events
S., Suri Orissa Disaster: Agony of the Living 相似文献
874.
The Accuracy of Mortality Reporting in Displaced Persons Camps During the Post-emergency Phase 总被引:2,自引:0,他引:2
For humanitarian organisations, accurate data are essential to identify emerging health problems and determine programme needs. We visited 45 post-emergency phase displaced persons camps and collected three months' mortality data which we compared with organisations' routine mortality reports. Organisations reported 612 deaths and we identified 741 deaths, for a mortality-reporting ratio, defined as the number of organisation-reported deaths divided by the number of investigator-identified deaths, of 83 per cent. For the majority of camps which under-reported deaths, mortality reporting ratios were significantly higher for women than men, and for camps with central mortality registers rather than those without. In the few camps which over-reported deaths, these occurred primarily among children younger than five years of age, probably due to the inclusion of abortions and stillbirths. Despite the overall under-reporting of deaths by humanitarian organisations, the existing health information systems appear to estimate mortality rates adequately in these post-emergency camps. However, organisations should improve the precision and completeness with which they report the characteristics of deaths in order to provide valuable data to target their programmes at the most vulnerable people. 相似文献
875.
876.
Nitrogen (N) pollution is a growing concern in forests of the greater Sierra Nevada, which lie downwind of the highly populated
and agricultural Central Valley. Nitrogen content of Letharia vulpina tissue was analyzed from 38 sites using total Kjeldahl analysis to provide a preliminary assessment of N deposition patterns.
Collections were co-located with plots where epiphytic macrolichen communities are used for estimating ammonia (NH3) deposition. Tissue N ranged from 0.6% to 2.11% with the highest values occurring in the southwestern Sierra Nevada (range:
1.38 to 2.11). Tissue N at 17 plots was elevated, as defined by a threshold concentration of 1.03%. Stepwise regression was
used to determine the best predictors of tissue N from among a variety of environmental variables. The best model consisted
only of longitude (r
2 = 0.64), which was reflected in the geographic distribution of tissue values: the southwestern Sierra Nevada, the high Sierras
near the Tahoe Basin, and the Modoc Plateau, are three apparent N hotspots arranged along the tilted north–south axis of the
study area. Withholding longitude and latitude, the best regression model suggested that NH3 estimates and annual number of wetdays interactively affect N accumulation (r
2 = 0.61; % N ∼ NH3 + wetdays + (NH3 × wetdays)). We did not expect perfect correspondence between tissue values and NH3 estimates since other N pollutants also accumulate in the lichen thallus. Additionally, other factors potentially affecting
N content, such as growth rate and leaching, were not given full account. 相似文献
877.
Huang DJ Zhang YM Song G Long J Liu JH Ji WH 《Environmental monitoring and assessment》2007,128(1-3):483-488
The Yellow River, the second largest river in China, is the most important resource of water supply in North China. In the
last 40 years, even in the upper Yellow River, with the development of industry and agriculture, more and more contaminants
have been discharged into this river and greatly polluted the water. Although a routine chemical component analysis has been
performed, little is known about the real toxic effects of the polluted water on organisms at environmental level. To explore
whether the pollutants induced oxidative stress and damage to aquatic organisms, malondialdehyde (MDA) level and activities
of superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione S-transferase (GST) in hepatopancreas,
kidney and intestine of the field-collected carp Cyprinus carpio from a mixed polluted (Lanzhou Region, LZR) and a relatively unpolluted (Liujiaxia Region, LJXR) sites of the upper Yellow
River were measured. The results showed that when the values of LZR compared with those of LJXR, SOD and GST activities increased
and GPx activity decreased significantly in all the three organs (P < 0.05–0.01); CAT activity decreased but MDA level increased significantly (P < 0.05–0.01) only in kidney and intestine. In conclusion, the results of this study suggest that the pollutants can induce
obvious oxidative damage in the carp, and the SOD, GST and GPx might be better indicators for the oxidative damage in aquatic
organisms. 相似文献
878.
Jebali J Banni M de Almeida EA Boussetta H 《Environmental monitoring and assessment》2007,124(1-3):195-200
Levels of the oxidative DNA damage 7, 8-dihydro-8-oxo-2′-deoxyguanosine (8-oxodG) and catalase (CAT) activity were measured
in the digestive gland and gills of clams Ruditapes decussatus, related to the presence of pollutants along Tunisian marine environment. Increased levels of CAT were observed in tissues
of clams from all the sites studied, compared to control values, and elevated 8-oxodG levels were observed at specific sites.
Results obtained in this work indicate that the measurement of 8-oxodG levels and CAT activity in tissues of R. decussatus is promising in pollution monitoring studies of the Tunisian marine environment. 相似文献
879.
This study evaluated the effects of an industrial wastewater treatment plant (IWTP) and a municipal wastewater treatment plant (MWTP) effluents on a variety of bioindicators ranging from biochemical, organism, and population-level responses in pale chub (Zacco platypus) and fish community structure. The Index of Biotic Integrity (IBI) indicated that the site upstream of these wastewater treatment plant discharges is in fair–good condition and downstream of the plant is in poor condition. The EROD (ethoxyresorufin-O-deethylase) activity, condition factor, and liver somatic index were significantly increased at the downstream site compared to those of the upstream site. The most significant change observed in pale chub population in the downstream site of the Miho Stream, relative to the upstream population, was the total absence of an younger age group. Stressors impacting the downstream site were identified as mostly organic or nutrient enrichment and habitat degradation associated with wastewater treatment plants. The results of causal analysis suggest that the primary causes affecting fish population in the downstream site are through both size-selective mortality caused by ammonia toxicity and recruitment failure caused by habitat degradation and reproduction problem due to an IWTP and MWTP effluents. 相似文献
880.
Ambient particles vary greatly in their ability to affect visibility, climate and human health. The fine fraction of aerosol
is responsible for greater and wider effects on human health; thus, investigation of this fraction is very important. Continuous
measurements of PM2.5 (particulate matter below 2.5 μm in size) concentrations at the Preila monitoring station started in
2003. During a period of 2 years, the episodes of high daily and semi-hourly concentrations of PM2.5 were measured. These
episodes did not depend on the season or time of day. The substantial role of long-range transport of pollutants to these
increases in concentration was shown using chemical and statistical analysis. It was found that most of the severe episodes
occurred when air masses came from a specific site besides it was established that air masses of different origin were characterized
by different mixing layer depth. Lower mixing depth was observed in air masses characterized by higher observed concentrations
at the measuring site and vice versa. PM2.5 concentrations showed diurnal and seasonal variations whose pattern reflected
the regional origin of the aerosol. The regional pollution level was evaluated by the statistical analysis of PM2.5 concentrations.
The background annual average of PM2.5 mass concentration for the eastern coast of the Baltic Sea was 15.1 ± 0.8 μg m−3. 相似文献