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161.
The unlimited economic growth that fuels capitalism's metabolism has profoundly transformed a large portion of Earth. The resulting environmental destruction has led to an unprecedented rate of biodiversity loss. Following large-scale losses of habitats and species, it was recognized that biodiversity is crucial to maintaining functional ecosystems. We sought to continue the debate on the contradictions between economic growth and biodiversity in the conservation science literature and thus invite scholars to engage in reversing the biodiversity crisis through acknowledging the impacts of economic growth. In the 1970s, a global agenda was set to develop different milestones related to sustainable development, including green–blue economic growth, which despite not specifically addressing biodiversity reinforced the idea that economic development based on profit is compatible with the planet's ecology. Only after biodiversity loss captured the attention of environmental sciences researchers in the early 2000s was a global biodiversity agenda implemented. The agenda highlights biodiversity conservation as a major international challenge and recognizes that the main drivers of biodiversity loss derive from economic activities. The post-2000 biodiversity agendas, including the 2030 Agenda for Sustainable Development and the post-2020 Convention on Biological Diversity Global Strategy Framework, do not consider the negative impacts of growth-oriented strategies on biodiversity. As a result, global biodiversity conservation priorities are governed by the economic value of biodiversity and its assumed contribution to people's welfare. A large body of empirical evidence shows that unlimited economic growth is the main driver of biodiversity loss in the Anthropocene; thus, we strongly argue for sustainable degrowth and a fundamental shift in societal values. An equitable downscaling of the physical economy can improve ecological conditions, thus reducing biodiversity loss and consequently enhancing human well-being.  相似文献   
162.
We aimed to analyse the influence of cholesterol and triglycerides, and of tobacco, coffee and alcohol consumption upon correlations between serum concentrations of organochlorine compounds (OCs) in patients with exocrine pancreatic cancer (EPC). Incident cases of EPC diagnosed in eastern Spain were prospectively identified (N=144). OCs were analysed by high-resolution gas chromatography with electron-capture detection. A strong correlation was observed between hexachlorobenzene (HCB) and beta-hexachlorocyclohexane (beta-HCH) (Spearman's rho=0.758). beta-HCH showed rho>0.4 with p,p'-DDT, p,p'-DDE, PCB138 and PCB153 (all p<0.001). Some correlations among compounds were slightly affected by tobacco, coffee or alcohol consumption. We observed a striking diversity of correlation patterns by strata of cholesterol and triglycerides. Most correlations were higher in the lowest category of triglycerides than in the lowest category of cholesterol. Most coefficients above 0.7 were seen in the lowest category of triglycerides (e.g., OC pairs p,p'-DDT and HCB, p,p'-DDT and beta-HCH, p,p'-DDE and beta-HCH, or HCB and beta-HCH). Correlations among OCs may be stronger when concentrations of triglycerides are low than when they are high. This is compatible with a dilution in the early phases of cancer and with a concentration effect as triglycerides become lower in the advanced phases of the disease.  相似文献   
163.
The application of the electrochemical speciation of heavy metals in tracking groundwater is presented. Three fractions interchangeable, associated to the organic materials and associated to the matter in suspension of the metals Zn, Cd, Pb and Cu by means of the anodic stripping voltammetry were determined. The parameters of the determination were: electrodeposition potential ‐1.2 V, time of deaerating with nitrogen 300 s, time of the electrolysis 90 s (with stirring) and the rest time 40 s. The core of this work was to determine the validity of this scheme of electrochemical speciation in the pursuit of the follow‐up of groundwater pollution caused by heavy metals after the breakdown of the mining raft at the River Guadiamar Basin (Andalusia, Spain).  相似文献   
164.
Three different methods for the sequential extraction of heavy metals from soil (viz those of Tessier et al. (A. Tessier, P.G. Campbell and N. Bisson (1979). Anal. Chem., 51, 844.), Sposito et al. (G. Sposito, L.J. Lund and A.C. Chang (1989). Soil. Sci. Soc. Am. J., 46, 260.) and Mann and Ritchie (S.S. Mann and G.S.P. Ritchie (1993). Aust. J. Soil Res., 31, 255.)) were examined in terms of the distribution of Cu, Zn and Pb in the soil phases and the bioavailability of these elements in soil. To this end, several samples of soils polluted with metals from a copper mine were fractionated by using the three studied methods and analyzed by atomic absorption spectrometry. The results revealed differences in extraction efficiency among the methods due to the extractant used, or its concentration, and to the soil/solution ratio. The three methods were found to provide accurate heavy metal background contents. However, the method of Tessier et al. is to be preferred for quantifying increased levels of heavy metals on account of its high extraction power.  相似文献   
165.
The continuous increase in world energy demand will lead to an energy crisis due to the limited availability of fossil fuels. Furthermore, the use of this energetic resource is responsible for the accumulation of greenhouse gases in atmosphere that is associated with several negative effects on environment. Therefore, it is worth to search for different energy supplies that are renewable and environmentally friendly—carbon neutral fuel. Microalgae are photosynthetic microorganisms that can achieve high oil contents. This oil is suitable for producing biodiesel; thus, microalgae are considered a promising sustainable energetic resource that can reduce the dependence on fossil fuel. Biodiesel production from microalgae includes several steps, such as cell cultivation and harvesting, oil extraction and biodiesel synthesis. Although several attempts have been made to improve biodiesel yields from microalgae, further studies are required to improve biodiesel production rates and to reduce the associated costs. This review shows the recent developments on biodiesel production from microalgae, emphasizing two process concepts: (1) indirect route, in which, after a facultative cell wall disruption method, microalgal oil is recovered in an appropriate solvent and then converted into biodiesel through transesterification and (2) direct route, in which biodiesel is produced directly from the harvested biomass. High biodiesel yields are obtained when both routes are preceded by a cell wall disruption method. In the indirect route, it is possible to apply three different types of solvents to recover microalgal oil. Although there are several concerns about the application of organic solvents, the most promising and cost-effective alternative for lipid recovery is n-hexane. Comparing direct and indirect routes, this study demonstrates that although further studies are required to optimize biodiesel production from microalgae, the available information proposes that the direct route is the most efficient.  相似文献   
166.

Problem

This paper aims at examining the occupational accident rate in Spain in the olive oil mill industry. These mills produce olive oil by physical or mechanical, but not chemical procedures. Although Spain is the leading olive oil producer in the world with 1,200,000 tons/year and over 25% of the world olive farming area, the occupational accident rate in this sector has been little studied in the relevant scientific literature.

Method

Our study analyses all occupational accidents which occurred during 2004-2009, with or without sick leave, at 90 Andalusian olive oil mills covered by one of the biggest state insurance companies for accidents at work and occupational diseases (within the Spanish Social Security system).

Results and discussion

Slips or trips are the most frequent cause of occupational accidents in this sector, accounting for 14.86% of the cases. In second position, incorrectly coordinated bodily movements account for almost 13.51% of the accidents. Falls from height, 12.2% of the cases, are also statistically noteworthy. As for the seriousness of the injuries, entrapments are particularly important, since in 2.70% of the cases they result in the traumatic amputation of a part of the body. The analysis of accidents without sick leave reveals that a high number of incidents are caused by contact of the skin and eyes with hazardous substances (20% of the cases) and 10% of them involve superficial injuries.

Impact on the industry

This paper provides a clear and updated image of the accident rate in Spanish olive oil mills and can be a useful tool for the design and adequate adjustment of the management systems implemented in these plants to guarantee a satisfactory level of occupational health and safety by means of more efficient planning and monitoring of measures intended to reduce professional risks and improve working conditions.

Recommendations

Given not only the high incidence of falls on the same level and the potential seriousness of falls from different levels, but also the small, round fruit involved, with a high oil content and a hard round stone, it is extremely important to design and implement safe working procedures and specifically train both operatives and managers in charge of the tidiness, cleanliness and regular control of the premises and operations. The analysis of the accidents not requiring sick leave (mostly cases of contact with hazardous substances on the skin or eyes, or superficial injuries) clearly reveals that the use of suitable personal protective equipment and the relevant training are crucial issues.  相似文献   
167.
Environmental Chemistry Letters - A broad variety of materials of biological origin have been successfully used in recent decades for the removal of pollutants from waters. These biosorbents...  相似文献   
168.
Europe has a long history of human pressure on freshwater ecosystems. As pressure continues to grow and new threats emerge, there is an urgent need for conservation of freshwater biodiversity and its ecosystem services. However, whilst some taxonomic groups, mainly vertebrates, have received a disproportionate amount of attention and funds, other groups remain largely off the public and scientific radar. Freshwater mussels (Bivalvia, Unionida) are an alarming example of this conservation bias and here we point out six conceptual areas that need immediate and long-term attention: knowledge, threats, socioeconomics, conservation, governance and education. The proposed roadmap aims to advance research, policy and education by identifying the most pressing priorities for the short- and long-term conservation of freshwater mussels across Europe.  相似文献   
169.
Straining phenomena in bacteria transport through natural porous media   总被引:1,自引:0,他引:1  

Background, aim, and scope  

Transport of bacteria through natural porous media is an issue of increasing concern arising in several very important environmental processes. These include the percolation of bacteria from fecal waste to drinking water reservoirs, thus leading to a risk for human health, or the bioremediation of contaminated soils in which the bacteria are expected to travel long distances underground in order to reach contaminated areas and degrade chemicals originating from accidental spills. An understanding of bacterial retention and transport mechanisms in porous media would be of great help in the development of models able to predict the distance covered by bacterial suspensions in these situations.  相似文献   
170.
The main purpose of this paper is to discuss whether it is possible to achieve human development without or with less economic growth. For this to happen, it is important that developed countries can maintain high levels of human development while reducing the scale of production and consumption so that developing countries can achieve greater economic growth. Using panel data from 118 countries aggregated in ten blocks of countries, we assess the influence of “growth” on “development”, as proxied by a transformed variable “Social Human Development Index” (SHDI), controlling for the influence of geo-economic factors. In particular, we analyse whether developed countries present a weaker statistical relation between GDP and the social dimension of HDI than their less developed counterparts. Results reveal that the GDP elasticity of SHDI is higher in blocks of countries where the concentration of developing countries occurs than in blocks dominated by the presence of developed countries. Thus, it is possible to envisage that a slowdown in economic activity in developed countries may occur without great sacrifice of human development, at least when it is measured by health and education components. We interpret the findings as meaning that at an aggregate level there are conditions for development to occur without or with less growth.  相似文献   
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