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991.
Soudek P Petrová S Benešová D Dvořáková M Vaněk T 《Journal of environmental radioactivity》2011,102(6):598-604
Hydroponicaly cultivated plants were grown on medium containing uranium. The appropriate concentrations of uranium for the experiments were selected on the basis of a standard ecotoxicity test. The most sensitive plant species was determined to be Lactuca sativa with an EC50 value about 0.1 mM. Cucumis sativa represented the most resistant plant to uranium (EC50 = 0.71 mM). Therefore, we used the uranium in a concentration range from 0.1 to 1 mM.Twenty different plant species were tested in hydroponic solution supplemented by 0.1 mM or 0.5 mM uranium concentration. The uranium accumulation of these plants varied from 0.16 mg/g DW to 0.011 mg/g DW. The highest uranium uptake was determined for Zea mays and the lowest for Arabidopsis thaliana. The amount of accumulated uranium was strongly influenced by uranium concentration in the cultivation medium. Autoradiography showed that uranium is mainly localized in the root system of the plants tested. Additional experiments demonstrated the possibility of influencing the uranium uptake from the cultivation medium by amendments. Tartaric acid was able to increase uranium uptake by Brassica oleracea and Sinapis alba up to 2.8 times or 1.9 times, respectively. Phosphate deficiency increased uranium uptake up to 4.5 times or 3.9 times, respectively, by Brassica oleracea and S. alba. In the case of deficiency of iron or presence of cadmium ions we did not find any increase in uranium accumulation. 相似文献
992.
Arun?Rijal Carsten?Smith-HallEmail author Finn?Helles 《Environment, Development and Sustainability》2011,13(1):121-140
Rural households throughout the Himalayas are regarded as dependent on non-timber forest products (NTFPs), but very few studies
have quantified this dependency. This case study, undertaken in two villages in the Central Himalayan foot hills in Nepal,
documents the absolute and relative importance of commercial NTFPs to rural household economies. Data were collected in a
one-year period and included interviews with 250 households using a semi-structured questionnaire and monthly interviews with
four sub-local NTFP traders, two local traders and two central wholesalers. The conservative estimate of NTFP-derived cash
income showed this to be a cornerstone in poorer household livelihood strategies and thus in poverty prevention. An annual
average of 578 kg of commercial NTFPs was collected in the wild per household, providing poorer households with a cash income
share of 44–78%. Better off households are not NTFP dependent but rely on income from crop production and livestock. Based
on a net marketing margin analysis, showing that harvesters capture a large share of the Indian wholesaler price, it is argued
that there is scope for pursuing NTFP-based strategies for poverty reduction through leasehold forestry and agroforestry.
Both these options are compatible with conserving forest cover and forest corridor functions and may thus present a win–win
scenario for livelihood improvement and conservation. 相似文献
993.
Ali?Mohammed?OumerEmail author Andreas?de Neergaard 《Environment, Development and Sustainability》2011,13(3):547-564
The aim of this paper is to disclose livelihood strategy-poverty links and gain a better understanding by developing typologies
of rural households. Based on qualitative and quantitative data, we group households into different typologies and explore
interactions. We identified six main agronomic strategies, four dominant livelihood diversification strategies, and income
quartiles (proxies for poverty) using cluster and principal component factor analysis. We found that nearly 82% of the surveyed
farmers in the study area belong to the bottom income quartiles while about 18% are on the upper quartiles. Households in
the bottom income quartiles engaged in casual off-farm work and cereal-dominated livelihood strategies that tend to pursue
subsistence farming by growing cereals and oil crops. Contrarily, farmers in the upper income quartiles adapted intensive
agronomic strategies by integrating root crops, legumes, and vegetables with livestock. This was largely attributed to access
to key livelihood assets such as land, livestock, education, and institutional support in which the upper quartiles were more
endowed. Improving availability of the key assets for the bottom income quartiles might be a way out of poverty and ensuring
sustainable development. It is crucial to recognize local-level heterogeneities of rural households when targeting development
interventions. 相似文献
994.
Duc?Luong?NguyenEmail author Nowarat?Coowanitwong 《Environment, Development and Sustainability》2011,13(3):565-585
Recognition has grown among policy-makers that early in the decision-making process, there is a need for an environmental
assessment of the effects of the policy, plan, and program (PPP) and their alternatives. Strategic environmental assessment
(SEA) is widely recognized as a supporting tool that systematically integrates environmental aspects into strategic decision-making
processes, thereby contributing to sustainable development. In this study, SEA was applied for an integrated assessment of
environmental, social, and economic impacts of a wide range of scenarios for transport-related air quality policies to help
decision-makers in identifying the most sustainable scenario with the purpose of reducing carbon monoxide (CO) concentrations
from transport emissions in Hanoi City, Vietnam. In conducting SEA process, the urban air dispersion model MUAIR was used
as a quantitative tool in prediction of CO concentrations. To evaluate the predicted impacts of scenarios, the SEA objectives
concerning sustainability and the corresponding sustainable indicators were identified. Based on the likely significant predicted
impacts on landscape, biodiversity, and health benefits, mitigation measures were proposed. These included planning in infrastructure
development and implementation of public education campaign. The results of predicted and evaluated impacts of scenarios as
well as proposed mitigation measures were taken into account for supporting sound decision-making that is consistent with
the principles of sustainable development. Considering sustainable impacts of the scenarios, the SEA result clearly indicates
that a combination of policy for public transport development and policy for installation of oxidation catalytic converter
for motorcycles is the most sustainable scenario for reducing CO concentrations from transport emissions. 相似文献
995.
The scientific field of impact assessment encompasses various ‘traditions’, each reflecting a set of particular policy objectives.
This paper analyses two types of impact assessment. Regulatory impact analysis focuses on better regulation and competitiveness,
while sustainability assessment fosters a holistic approach centred on the values of sustainable development. Through an analysis
of the political discourses at the level of the European Union and at the sub-national level of the Flemish Region of Belgium,
elements of convergence between the better regulation and sustainable development discourse are identified. The paper analyses
how integrated impact assessment can be an integrative tool that allows to merge both discourses and to implement them in
day-to-day decision-making. The potential of the existing Flemish regulatory impact analysis framework to be the starting
point of an integrated assessment scheme for sustainable development is advocated and motivated. 相似文献
996.
Kukutschová J Moravec P Tomášek V Matějka V Smolík J Schwarz J Seidlerová J Safářová K Filip P 《Environmental pollution (Barking, Essex : 1987)》2011,159(4):998-1006
The paper addresses the wear particles released from commercially available “low-metallic” automotive brake pads subjected to brake dynamometer tests. Particle size distribution was measured in situ and the generated particles were collected. The collected fractions and the original bulk material were analyzed using several chemical and microscopic techniques. The experiments demonstrated that airborne wear particles with sizes between 10 nm and 20 μm were released into the air. The numbers of nanoparticles (<100 nm) were by three orders of magnitude larger when compared to the microparticles. A significant release of nanoparticles was measured when the average temperature of the rotor reached 300 °C, the combustion initiation temperature of organics present in brakes. In contrast to particle size distribution data, the microscopic analysis revealed the presence of nanoparticles, mostly in the form of agglomerates, in all captured fractions. The majority of elements present in the bulk material were also detected in the ultra-fine fraction of the wear particles. 相似文献
997.
Raud M Tutt M Jõgi E Kikas T 《Environmental science and pollution research international》2011,19(7):3039-3045
Introduction
Two semi-specific microbial biosensors were constructed for the analysis of biochemical oxygen demand (BOD) in high-cellulose-content pulp and paper industry wastewaters. The biosensors were based on living cells of Bacillus subtilis and Paenibacillus sp. immobilized in an agarose gel matrix. Semi-specific microorganisms were isolated from various samples (decaying sawdust and rabbit manure) and were chosen based on their ability to assimilate cellulose.Materials &; methods
The biosensors were calibrated with the Organization for Economic Cooperation and Development synthetic wastewater, and measurements with different wastewaters were conducted.Results
The response time of biosensors using the steady-state method was 20?C25 min, and the service life of immobilized microorganisms was 96 days. Detection limit was 5 mg/l of BOD7 while linear ranges extended up to 55 and 50 mg/l of the BOD7 for B. subtilis- and Paenibacillus sp.-based biosensors, respectively. Repeatability and reproducibility of both biosensors were within the limits set by APHA??less than 15.4%. In comparison, both biosensors overestimated the BOD7 values in paper mill wastewaters and underestimated the BOD7 in aspen pulp mill wastewater.Conclusions
The semi-specific biosensors are suitable for the estimation of organic pollution derived from cellulose, while the detection of pollution derived from tannins and lignins was minor. Better results in terms of accuracy and repeatability were gained with Paenibacillus sp. biosensor. 相似文献998.
H Segner M Wenger AM Möller B Köllner A Casanova-Nakayama 《Environmental science and pollution research international》2011,19(7):2465-2476
Numerous environmental chemicals, both long-known toxicants such as persistent organic pollutants as well as emerging contaminants such as pharmaceuticals, are known to modulate immune parameters of wildlife species, what can have adverse consequences for the fitness of individuals including their capability to resist pathogen infections. Despite frequent field observations of impaired immunocompetence and increased disease incidence in contaminant-exposed wildlife populations, the potential relevance of immunotoxic effects for the ecological impact of chemicals is rarely considered in ecotoxicological risk assessment. A limiting factor in the assessment of immunotoxic effects might be the complexity of the immune system what makes it difficult (1) to select appropriate exposure and effect parameters out of the many immune parameters which could be measured, and (2) to evaluate the significance of the selected parameters for the overall fitness and immunocompetence of the organism. Here, we present - on the example of teleost fishes - a brief discussion of how to assess chemical impact on the immune system using parameters at different levels of complexity and integration: immune mediators, humoral immune effectors, cellular immune defenses, macroscopical and microscopical responses of lymphoid tissues and organs, and host resistance to pathogens. Importantly, adverse effects of chemicals on immunocompetence may be detectable only after immune system activation, e.g., after pathogen challenge, but not in the resting immune system of non-infected fish. Current limitations to further development and implementation of immunotoxicity assays and parameters in ecotoxicological risk assessment are not primarily due to technological constraints, but are related from insufficient knowledge of (1) possible modes of action in the immune system, (2) the importance of intra- and inter-species immune system variability for the response against chemical stressors, and (3) deficits in conceptual and mechanistic assessment of combination effects of chemicals and pathogens. 相似文献
999.
Rožič PŽ Dolenec T Baždarić B Karamarko V Kniewald G Dolenec M 《Environmental science and pollution research international》2011,19(7):2708-2721
Introduction and purpose
Studies examining the environmental impact of marine aquaculture have increased significantly in number during the last few decades. The present paper investigates a region of rapid growth in intensive aquaculture and its influence on the local marine ecosystem.Discussion
This study was undertaken with the specific aim of assessing the effect of fish farming on marine sediment at a farm near the island of Vrgada in the Central Adriatic. Data obtained regarding major (Si, Al, K, Na, Fe, Ca, Mg), minor (Mn, P, Ti) and trace (As, Au, Ba, Cd, Co, Cr, Cs, Cu, Ga, Hf, Hg, Mo, Nb, Ni, Pb, Rb, Sb, Sc, Se, Sr, Ta, Th, Tl, U, V, Y, Zn, Zr) elements were used to estimate the spatial and temporal distribution of metals in the sediment and their possible relationship with local aquacultural activity.Results
Although the measured concentrations of heavy metals in sediment below fish cages were notably different and potentially a result of farming activity, the values were generally lower than background concentrations observed in the Central Adriatic. In contrast, concentrations of heavy metals at a reference site unaffected by aquaculture varied from lower levels to values even higher than those observed below the high-production cages. Furthermore, calculated environmental index values indicate that the sediment below the farm is either uncontaminated or suffers from only low levels of contamination.Conclusion
Such results suggest that the effect of observed fish farm activity on the local marine ecosystem is practically negligible. 相似文献1000.
Trnovec T Dedík L Jusko TA Lancz K Palkovičová L Kočan A Šovčíková E Wimmerová S Tihányi J Patayová H Hertz-Picciotto I 《Chemosphere》2011,85(11):1687-1693
Investigators have typically relied on a single or few discrete time points as measures of polychlorinated biphenyl (PCB) body burden, however health effects are more likely to be the result of integrative exposure in time, optionally expressed as an area under the time curve (AUC) of PCB serum concentration. Using data from a subgroup of 93 infants from a birth cohort in eastern Slovakia—a region highly polluted by PCBs—we fit a system type model, customized to our longitudinal measures of serum PCB concentrations in cord, 6, 16, and 45 month blood specimens. The most abundant congener, PCB 153, was chosen for modeling purposes. In addition to currently used methods of exposure assessment, our approach estimates a concentration time profile for each subject, taking into account mean residence time of PCB 153 molecules in the body, duration of breast feeding, hypothetical PCB 153 concentration in steady-state without breast feeding and alternately without normal food intake. Hypothetical PCB 153 concentration in steady-state without normal food intake correlates with AUC (r = 0.84, p < 0.001) as well as with duration of breast feeding (r = 0.64, p < 0.001). It makes possible to determine each subject’s exposure profile expressed as AUC of PCBs serum concentration with a minimum model parameters. PCB body burden in most infants was strongly associated with duration of breast feeding in most, but not all children, was apparent from model output. 相似文献