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331.
Abstract

Prevention of marine pollution, particularly in semi-enclosed seas, embayments and areas with limited exchange of water, requires a well conceived and harmonized legal system, specified standards, a monitoring programme, and effective control and enforcement capabilities. This comprehensive approach is often called a strategy. Three generations of strategies have been devised and applied historically in Europe and North America, each a step further in integrating environmental protection, technical advancement and economic capabilities. the overpowering socio-economic problems of transition from a centrally planned to a market economy, a task facing a dozen central and eastern European coastal states, compound the problem of application of an integrated approach.

No management strategy can achieve its set goals unless based on scientific evidence. the data base has to offer information on two basic questions, one specific and one of a general nature.

The specific question is: Has the area under consideration some features, an activity, or one or more living species, which must be protected at any cost? the answer to this question will invoke the precautionary principle into strategic considerations, and leads to the general question: What is the carrying (= assimilative or environmental) capacity for each activity and for the discharge of each contaminant into the impacted area? Answers to these questions lead to the choice of the strategy for environmental management.  相似文献   
332.
The behaviour of Portland cement with and without 30% fly ash addition in aggressive solutions was studied. This paper considers the sulphate corrosion of the hardened cement paste. The cement paste test samples were prepared, cured in water for 21 day and then exposed to the influence of aggressive environment (10% (NH4SO4 solution). The measurements of several properties were carried out and the results were analyzed.

The image of the surface composition and morphology of the cement paste test samples was made by scanning electron microscopy (SEM). Concentration gradient of sulphate ions in cement paste depth was obtained by energy‐dispersive analysis (EDS).  相似文献   
333.
Association of selected essential (Co, Cu, Fe, Mn, Mo, Se, and Zn) and nonessential (Cd, Pb) trace elements with cytosolic proteins of different molecular masses was described for the liver of European chub (Squalius cephalus) from weakly contaminated Sutla River in Croatia. The principal aim was to establish basic trace element distributions among protein fractions characteristic for the fish living in the conditions of low metal exposure in the water. The fractionation of chub hepatic cytosols was carried out by size exclusion high performance liquid chromatography (SE-HPLC; Superdex? 200 10/300 GL column), and measurements were performed by high resolution inductively coupled plasma mass spectrometry (HR ICP-MS). Elution profiles of essential elements were mostly characterized by broad peaks covering wide range of molecular masses, as a sign of incorporation of essential elements in various proteins within hepatic cytosol. Exceptions were Cu and Fe, with elution profiles characterized by sharp, narrow peaks indicating their probable association with specific proteins, metallothionein (MT), and ferritin, respectively. The main feature of the elution profile of nonessential metal Cd was also single sharp, narrow peak, coinciding with MT elution time, and indicating almost complete Cd detoxification by MT under the conditions of weak metal exposure in the water (dissolved Cd concentration ≤0.3 μg L?1). Contrary, nonessential metal Pb was observed to bind to wide spectrum of proteins, mostly of medium molecular masses (30–100 kDa), after exposure to dissolved Pb concentration of ~1 μg L?1. The obtained information within this study presents the starting point for identification and characterization of specific metal/metalloid-binding proteins in chub hepatic cytosol, which could be further used as markers of metal/metalloid exposure or effect on fish.  相似文献   
334.
As an indicator of environmental pollution, we collected tree rings and bark of linden (Tilia platyphyllos Scop.) from four sampling locations in Serbia. Mn and Pb were determined with a spectrochemical method that has an argon-stabilized U-shaped DC arc with aerosol supply as excitation source. Increased concentrations of Mn in linden tree rings and bark were found at the Debeli Lug location, where the Mn transfer factors were largest. The availability of Mn in soil and tree rings was greatly influenced by pH. Since 1950, Mn level decreased more noticeably on acidic soils. Higher concentrations of Pb were found in linden tree rings and bark at the locations Fru?ka Gora and Zemun. Proximity of the road to Novi Sad at both sites may be a possible reason for this. The Pb transfer factor was highest at Fru?ka Gora. The ratio of bioavailable elements in soil for Mn and Pb were also calculated. Close correlations between Mn and Pb concentrations in linden tree rings and the ratio of bioavailable elements in soil were seen at all four locations.  相似文献   
335.
The presence of sewage-borne micro contaminants in environmental waters is directly related to the discharge of treated effluents from wastewater treatment plants (WWTP) and the flow rate of the receiving river waters. Mediterranean rivers, in particular, are characterized by important fluctuations in the flow rates and heavy pollution pressures resulting from extensive urban, industrial and agricultural activities. This translates into contamination levels in these rivers often higher than those in other larger European basins. The present work provides an overview of the occurrence of five groups of organic contaminants (131 compounds) namely pharmaceuticals, illicit drugs, polar pesticides, estrogens, alkylphenols and related ethoxylates in WWTP tertiary treatment effluents. Data gathered during a period of water reuse carried out in the lower stretch of the Llobregat river (NE Spain), in the surroundings of the town of Barcelona as a consequence of the severe drought that took place along the years 2007-2008 are presented as illustrative example. In general, measured concentrations of the target compounds were in the low to mid ng L−1 range. The total concentration of each compound class downstream to the discharge point was similar or slightly higher than that found upstream. Regarding the loads calculated for each compound, the relative contribution from the river upstream and the tertiary effluent were highly compound depending with no apparent trend. However, estimation of the overall bulk loads for each compound class determined in the Llobregat river showed the following rank order: pharmaceuticals > alkylphenols > pesticides > illicit drugs ? estrogens.  相似文献   
336.
In this article, several findings on socio-economic conditions derived from national reports and a web-based questionnaire are discussed and related to the changing role of forestry and the future forest policy development. A number of Central and South-eastern European countries taking part in a SEE-ERA-NET project ReForMan project (www.reforman.de) participated in data acquisition: Austria, Bosnia and Herzegovina, Croatia, Germany, Serbia and Slovenia. The aim of the research was to illustrate the present structure of forestry sector, as well as investigate newly emerging topics in forestry of Central and South-eastern Europe. The results indicated certain patterns in attitudes and perceptions among stakeholders that can be related to socio-economic conditions defined for each country. Clear differences between member and non-member countries exist only in level of implementation of EU legislation. Results showed consensus on main threats to the forests among all countries, but also some country specifics in perceptions of factors influencing forestry, their importance and professional competencies. These results could be additionally explained by influence of historical conditions which shaped development of forest sector in SEE region especially in its organizational dimension as well as in perceived role of forestry expressed through recognition of main forest functions. The influence of European forest policy processes in the region is evident through adaptation of EU legislation and perceived implications of international processes on national levels. Based on this observation, two possible options for future development of the forestry sector can be foreseen: (i) focusing on the productive function of forests and fostering its' sustainable use; or (ii) putting an emphasis on environmental and social issues. In both cases supporting public participation in decision-making processes is recommendable. Another conclusion based on perceived medium to low professional competencies to cope with new topics, that there is lack of confidence and need for professional support in decisionmaking processes.  相似文献   
337.
Polycyclic aromatic hydrocarbons (PAHs) were measured together with inorganic air pollutants at two urban sites and one rural background site in the Banja Luka area, Bosnia and Hercegovina, during 72 h in July 2008 using a high time resolution (5 samples per day) with the aim to study the spatial and temporal variabilities and to explore the significance of averaging effects inherent to 24 h-sampling. Measurement uncertainty was quantified on basis of three independent side-by-side samplers, deployed at one of the sites.PAH abundances in the urban and rural environments differed largely. Levels at the urban sites exceeded the levels at the rural site by >100%. The discrepancy was largely dominated by emission of 3–4 ring PAHs in the city, while 5–6 ring PAHs were more evenly distributed between city sites and the hill site. During the night a higher fraction of the semivolatile PAHs might have been stored in the soil or sorbed to surfaces. PAH patterns were undistinguishable across the three sites. However, concentrations of more particle-associated substances differed significantly between the urban sites than between one of the urban sites and the rural site (3σ uncertainty). Time-averaging (on a 24 h-basis) would have masked the significant inter-site differences of half of the substances which were found at different levels (on a 4 h-basis).  相似文献   
338.

Background, aim and scope  

Precipitation samples collected from 1995 to 2000 at meteorological station in the eastern outskirts of Herceg Novi (Montenegro) were analysed on Na+, K+, Mg2+, Ca2+, Cl, SO4 2–, NO3 and NH4 +. Four-day backward trajectory simulations were conducted during the precipitation period to investigate the regional transport of main ions and their deposition in the region of the southeastern Adriatic Sea. The air mass trajectories were classified into six trajectory categories by the origin and direction of their approach to Herceg Novi.  相似文献   
339.
The synthesis of telechelic polyacetals with terminal hydroxyl groups (polyacetal polyols), by the reaction of triethylene glycol divinyl ether with dipropylene glycol in the presence of trimethylolpropane or other triols or diols as starters, in acidic catalysis, has been studied. The synthesized liquid polyacetal triols and polyacetal diols were characterized by hydroxyl number, viscosity, acidity, number average molecular weight (Mn), weight average molecular weight (Mw), molecular weight distribution (Mw/Mn), FT-IR spectra. The obtained polyacetals were transformed in cast elastomers by the reaction with the isocyanate Mondur CD (modified diphenyl methane diisocyanate) with properties very close to the elastic polyurethanes obtained by using conventional polyether triols, copolymers propylene oxide–ethylene oxide. The polyacetal polyols are suitable for the synthesis of elastic polyurethanes (polyurethane elastomers, flexible polyurethane foams). Polyacetals are well known biodegradable polymers. Therefore, the polyurethanes based on polyacetal polyols are expected to be biodegradable.  相似文献   
340.
The study was aimed at determining the levels of metals in water samples and muscles of the fish caught in the Una River basin, located in the northwestern part of Bosnia and Herzegovina. For that purpose, three fish species: Brown Trout (Salmo trutta m. fario), Grayling (Thymallus thymallus) and Californian Trout (Salmo gairdneri), together with stem water samples, were analyzed for metal concentrations (Pb, Hg, Cd, As, Mn, Ni, Cu, Cr, Se, Co, Sn, Zn, Fe, Ca, P) during a 2-year period. The fish was captured using electric fishing, nets or fishing equipment. The capture was undertaken on three sites (the river source, the middle flow and the river mouth) of each of the five biggest rivers belonging to the Una River basin (Unac, Krušnica, Sana, Klokot, and Una). The concentrations of metals in each sample were determined via atomic absorption spectrophotometry. In the tested waters, the presence of Mn in concentrations higher than permitted (0.07 mg/l) had been detected. In the tested meat, the following average concentrations of metals (mg/kg) had been found: Pb (0.67), Cd (0.06), Mn (0.65), Ni (0.15), Cu (0.79), Cr (1.05), Se (0.03), Zn (8.92), Fe (5.40), Ca (14.68), and P (10.85). The correlation between Mn concentrations identified in the tested waters and those identified in the meat of Brown Trout was revealed to be statistically significant, which confirms that, over time, bioaccumulation of metals took place. Even though the results were not indicative of contamination, they strongly suggest that constant monitoring of the ecosystems in reference should be implemented.  相似文献   
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