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101.
Broz J Grabic R Kilián J Lojkásek M Marklund S Ocelka T Pekárek V Pribyl J Tydlitát V Výska J 《Chemosphere》2000,41(12):1948-1911
The effect of synthetic and mineral oils on the formation of polyaromatic hydrocarbons (PAHs), polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and biphenyls (PCBs) in emissions from a spark ignition engine was studied on a Skoda Favorit engine fueled with leaded gasoline. The test cycle simulated urban traffic conditions on a chassis dynamometer, in accordance with the ECC 83.00 test. The data for selected PAHs as well as PCDDs, PCDFs, and PCBs congener profiles are presented. PCDD/Fs emissions for an unused oil and the oil after 10000-km operation varied from 300 to 2000 fmol/m3, PCBs emissions from 75 to 178 pmol/m3, and PAHs emissions from 150 to 420 microg/m3. The content of PCBs in oils varied from 2 to 920 mg/kg. 相似文献
102.
The chlorination and condensation of acetylene at low temperatures is demonstrated using copper chlorides as chlorinated agents coated to model borosilicate surfaces. Experiments with and without both a chlorine source and borosilicate surfaces indicate the absence of gas-phase and gas-surface reactions. Chlorination and condensation occur only in the presence of the copper catalyst. C2 through C8 organic products were observed in the effluent; PCDD/F were only observed from extraction of the borosilicate surfaces. A global reaction model is proposed that is consistent with the observed product distributions. Similar experiments with dichloroacetylene indicate greater reactivity in the absence of the copper catalyst. Reaction is observed in the gas-phase and in the presence of borosilicate surfaces at low temperatures. The formation of hexachlorobenzene is only observed in the presence of a copper catalyst. PCDD/F were only observed from extraction of the borosilicate surfaces. A global reaction model is proposed for the formation of hexachlorobenzene from dichloroacetylene. 相似文献
103.
Rafa Barquin 《国际发展与全球生态学杂志》2013,20(6):513-524
The aim of this paper is to check the hypothesis for the environmental Kuznets curve for sulfur dioxide. This involved analysis of: 1. the theoretical basis of the model; 2. the technical problem of SO2 generation; 3 the kind of information used in the estimations; 4. changes in the structure of electric energy production; 5. improvements in energy efficiency; and 6. the recent introduction of cleaning mechanisms in a favourable political context. The conclusion is that, if it is possible to prove the existence of environmental Kuznets curve models, their utility as instruments of economic policy is debatable. 相似文献
104.
KEVIN M. BROWN R. MICHAEL ERWIN MILO E. RICHMOND P. A. BUCKLEY JOHN T. TANACREDI DAVE AVRIN 《Environmental management》2001,28(2):207-224
During the 1980s, the exponential growth of laughing gull (Larus atricilla) colonies, from 15 to about 7600 nests in 1990, in the Jamaica Bay Wildlife Refuge and a correlated increase in the bird-strike
rate at nearby John F. Kennedy International Airport (New York City) led to a controversy between wildlife and airport managers
over the elimination of the colonies. In this paper, we review data to evaluate if: (1) the colonies have increased the level
of risk to the flying public; (2) on-colony population control would reduce the presence of gulls, and subsequently bird strikes,
at the airport; and (3) all on-airport management alternatives have been adequately implemented. Since 1979, most (2987, 87%)
of the 3444 bird strikes (number of aircraft struck) were actually bird carcasses found near runways (cause of death unknown
but assumed to be bird strikes by definition). Of the 457 pilot-reported strikes (mean = 23 ± 6 aircraft/yr, N= 20 years), 78 (17%) involved laughing gulls. Since a gull-shooting program was initiated on airport property in 1991, over
50,000 adult laughing gulls have been killed and the number of reported bird strikes involving laughing gulls has declined
from 6.9 ± 2.9 (1983–1990) to 2.6 ± 1.3 (1991–1998) aircraft/yr; nongull reported bird strikes, however, have more than doubled
(6.4 ± 2.6, 1983–1990; 14.9 ± 5.1, 1991–1998). We found no evidence to indicate that on-colony management would yield a reduction
of bird strikes at Kennedy Airport. Dietary and mark–recapture studies suggest that 60%–90% of the laughing gulls collected
on-airport were either failed breeders and/or nonbreeding birds. We argue that the Jamaica Bay laughing gull colonies, the
only ones in New York State, should not be managed at least until all on-airport management alternatives have been properly
implemented and demonstrated to be ineffective at reducing bird strikes, including habitat alterations and increasing the
capability of the bird control unit to eliminate bird flocks on-airport using nonlethal bird dispersal techniques. Because
the gull-shooting program may be resulting in a nonsustainable regional population of laughing gulls (>30% decline), we also
recommend that attempts be made to initiate an experimental colony elsewhere on Long Island to determine if colony relocation
is a feasible management option. 相似文献
105.
The aim of this paper is to assess the conditions that influence foreign direct investment in the mineral industries of China and India. The paper first surveys literature on the determinants of foreign direct investment to identify key conditions, under which host countries attract mining FDI. It then builds an evaluative framework which allows for comparative analysis. The paper then comparatively evaluates the performance of foreign investment regimes that govern mineral industries in China and India. Its findings show that the overall conditions for foreign mining investment in China and India are not favourable and that substantial policy, regulatory and other changes in both countries need to be made if more investment is to flow. 相似文献
106.
针对造纸法再造烟叶生产废水COD波动大、废水处理系统运行不稳定等问题,对造纸法再造烟叶的生产废水排放及不同种类废水的水质特点进行了分析。在废水处理系统运行检测数据的基础上,采用数理统计方法研究了废水COD与pH的关系。结果表明:COD与pH呈高度显著的线性关系;用得到的回归方程COD=-2 913pH+22 059对废水COD进行验证和预测,相对偏差在15%以内。本研究为造纸法再造烟叶废水处理系统的运行提供了一种快捷的COD预测方法,有助于提高废水处理系统的处理效率和运行稳定性。 相似文献
107.
Background, Aims and Scope When joining the European Union on 1st May 2004, Estonia had to conform its legislation to the European Union legislation.
In relation with that, also the treatment requirements on end-of-life vehicles proceeding from Directive 2000/53/EC of the
European Parliament and of the Council of 18 September 2000 were established in Estonia for the first time. Since this area
was not regulated with law beforehand, there was not any information available about it. The aim of the current survey was
to ascertain the condition of scrap yards in mid 2004. In addition to that, also to identify the number of scrap yards operating
in Estonia, to classify these by the number of dismantled vehicles and the potential environmental hazard, and to map the
locations of car dismantling companies and evaluate their compliance with the valid requirements.
Methods The companies that have been registered in the Commercial Registry under the activity code 503090-end-of-life vehicle dismantling
were visited and visually reviewed. During the visits, the compliance of scrap yards with the existing requirements was evaluated
and it was also attempted to identify how environmentally sound the dismantling technology of every scrap yard owner is.
Results and Discussion Altogether, 63 scrap yards operated in Estonia by mid 2004. Twelve of them dismantled more than 100 vehicles, 13 of them
51-99 vehicles and 38 up to 50 vehicles a year. The total annual market capacity on dismantling of vehicles in Estonia is
considered to be approx. 10,000 units. There are very few companies dealing only with car dismantling as the main business.
Most scrap-yard owners also offer side services, e.g. haulage, car repair and maintenance. The dismantlers are interested
in the selling of second-hand spare parts and scrap metal. Only one company out of 63 complied with all the requirements enacted
by the relevant decision of the Estonian Minister of Environment. The rest of the scrap yards did not meet the requirements
on the site on storage and treatment nor did they have the hazardous waste handling licence or the waste permit. Of the requirements
established for the site for storage of end-of-life vehicles, 97% of the scrap yards were surrounded with a fence, 67% had
a 24-hour guard, 45% had covered the areas with waterproof cover, but only 3% had an oil trap. Sites for treatment were in
a somewhat better condition, these were mostly situated inside the buildings, where floors were covered with waterproof covers.
Most of the dismantlers collected the waste oil and waste fluids into separate vessels, but there were a number of dismantlers
who did not know of existence of polychlorinated biphenyls (PCB) in car air conditioning systems and the availability of mercury
in sensors belonging in passenger safety systems. Proceeding from the general condition of the scrap yard, the rest of 62
scarp yards were distributed between two empirical parameters - 'rather environmentally hazardous' or 'rather not environmentally
hazardous'. As a matter of fact, 17% of scrap yards turned out 'rather environmentally hazardous'.
Conclusion Out of the scrap yards operating in Estonia, only one is compliant with the requirements set up by Directive 2000/53/EC.
Another 62 appeared during the review to be sites of potential environmental pollution. In order to comply with environmental
requirements and get the hazardous waste treatment license, the scrap yard owners have to invest into state-of-the-art dismantling
and environment protection equipment. The main obstacle to reach the environmentally sound scrap-yard is the high investment
cost and the black market for spare parts.
Recommendation and Outlook As the correction of the market in end-of-life vehicle treatment started after the adoption of Directive 2000/53/EC, the
environmental authorities have to look after the ongoing correction. It is because there is still a demand for cheap spare
parts and it makes it attractive to dismantle the vehicles out of scrap-yards by licensees. 相似文献
108.
Under the Kyoto Protocol the European Union agreed to reduce emissions of greenhouse gases by 8 percent. The Burden-Sharing Agreement (BSA) redistributes the reduction target among the member states. The purpose of this paper is to evaluate the BSA. To determine if cost efficiency was considered, marginal abatement costs (MACs) are first calculated based on an estimation of the directional output distance function using country production data for 1990-2000. MACs, together with equity indicators, are then regressed on the emission change targets. The main conclusion is that both efficiency and equity were important aspects considered in the settlement. 相似文献
109.
110.
Claudio S. Quilodrán Mathias Currat Juan I. Montoya‐Burgos 《Conservation biology》2018,32(5):1139-1149
Human‐induced habitat changes may lead to the breakdown of reproductive barriers between distantly related species. This phenomenon may result in fertile first‐generation hybrids (F1) that exclude the genome of one parental species during gametogenesis, thus disabling introgression. The species extinction risk associated with hybridization with genome exclusion is largely underappreciated because the phenomenon produces only F1 hybrid phenotype, leading to the misconception that hybrids are sterile and potentially of minor conservation concern. We used a simulation model that integrates the main genetic, demographic, and ecological processes to examine the dynamics of hybridization with genome exclusion. We showed that this mode of hybridization may lead to extremely rapid extinction when the process of genome exclusion is unbalanced between the interbreeding species and when the hybridization rate is not negligible. The coexistence of parental species was possible in some cases of asymmetrical genome exclusion, but show this equilibrium was highly vulnerable to environmental variation. Expanding the exclusive habitat of the species at risk allowed its persistence. Our results highlight the extent of possible extinction risk due to hybridization with genome exclusion and suggest habitat management as a promising conservation strategy. In anticipation of serious threats to biodiversity due to hybridization with genome exclusion, we recommend a detailed assessment of the reproductive status of hybrids in conservation programs. We suggest such assessments include the inspection of genetic content in hybrid gametes. 相似文献