全文获取类型
收费全文 | 1783篇 |
免费 | 23篇 |
国内免费 | 23篇 |
专业分类
安全科学 | 75篇 |
废物处理 | 81篇 |
环保管理 | 290篇 |
综合类 | 316篇 |
基础理论 | 377篇 |
环境理论 | 2篇 |
污染及防治 | 434篇 |
评价与监测 | 153篇 |
社会与环境 | 89篇 |
灾害及防治 | 12篇 |
出版年
2023年 | 19篇 |
2022年 | 29篇 |
2021年 | 40篇 |
2020年 | 22篇 |
2019年 | 29篇 |
2018年 | 49篇 |
2017年 | 45篇 |
2016年 | 62篇 |
2015年 | 47篇 |
2014年 | 61篇 |
2013年 | 104篇 |
2012年 | 89篇 |
2011年 | 104篇 |
2010年 | 74篇 |
2009年 | 94篇 |
2008年 | 95篇 |
2007年 | 109篇 |
2006年 | 75篇 |
2005年 | 82篇 |
2004年 | 72篇 |
2003年 | 61篇 |
2002年 | 64篇 |
2001年 | 43篇 |
2000年 | 30篇 |
1999年 | 26篇 |
1998年 | 24篇 |
1997年 | 19篇 |
1996年 | 21篇 |
1995年 | 26篇 |
1994年 | 15篇 |
1993年 | 13篇 |
1992年 | 21篇 |
1991年 | 11篇 |
1990年 | 21篇 |
1989年 | 12篇 |
1988年 | 10篇 |
1987年 | 6篇 |
1986年 | 11篇 |
1985年 | 10篇 |
1984年 | 14篇 |
1983年 | 12篇 |
1982年 | 9篇 |
1981年 | 6篇 |
1980年 | 3篇 |
1979年 | 5篇 |
1974年 | 5篇 |
1973年 | 4篇 |
1972年 | 4篇 |
1969年 | 3篇 |
1968年 | 3篇 |
排序方式: 共有1829条查询结果,搜索用时 406 毫秒
341.
J. N. Van Der Leij Dr. G. H. A. Visser M. Th. E. Bink-Boelkens J. F. Meilof C. G. M. Kallenberg 《黑龙江环境通报》1994,14(10):1003-1007
In this short communication we describe a patient with anti-SSA and anti-SSB antibodies whose first child died of congenital complete heart block (CCHB). During her second pregnancy she was treated with prednisolone, azathioprine, and plasmapheresis, and levels of anti-SSA and anti-SSB antibodies fell significantly. The pregnancy evolved uneventfully and resulted in the birth of an unaffected male infant. This is the fourth reported case of a successful outcome of pregnancy after treatment with immunosuppressive drugs in a woman with a significant risk of recurrence of CCHB. 相似文献
342.
Action spectroscopy of light-induced hatching ofArtemia cysts (Branchiopoda: Crustacea) 总被引:2,自引:0,他引:2
The action spectrum for the hatching ofArtemia cysts and the results of illumination experiments with decapsulated cysts suggest that a haempigment may be involved in light-induced hatching. The screening role of haematin is proposed. Starting from the assumption that haematin and the photoreceptor are both haempigments, we can attribute a hatching delaying or photoreceptor protective function to haematin.This work is part of F.K.F.O. Project No. 2.0012.82 相似文献
343.
344.
George Van Houtven Maureen L. Cropper 《Journal of Environmental Economics and Management》1996,30(3):348-368
Under certain environmental statutes the EPA is required to balance costs and benefits in setting standards, whereas under others this is prohibited. This paper examines EPA regulatory decisions made under three statues, two of which require balancing and one of which does not. Using discrete choice models, we find that costs and benefits are significant explanatory variables for all three sets of decisions. This suggests that balancing occurred in each case; however, the value (implicit in these decisions) of avoiding a cancer case varies widely. We also find that a 1987 court ruling effectively curtailed whatever balancing occurred under the statute that prohibited it. 相似文献
345.
Gino Van Begin 《Local Environment》2004,9(3):213-216
Since 1994, more than 2000 European local governments have adopted the principles of the Aalborg Charter as a basis for local sustainability action. Now, ten years later in June 2004, these local governments will gather once again in Aalborg, Denmark at the Fourth European Conference on Sustainable Cities and Towns in Europe, Inspiring Futures—Aalborg+10. The Aalborg+10 event will celebrate a decade of European local sustainability action, evaluate progress and stagnation, and, more importantly, will adopt new commitments to move from Agenda to Action. The conference will be crucial for accelerating local sustainability in Europe and to move towards Local Action. Here an overview is provided on the context against which this important conference is set and its expected outcomes. 相似文献
346.
C. J. M. Musters H. C. Van Latesteijn W. J. Ter Keurs 《Environmental monitoring and assessment》1988,10(3):181-203
Since 1963 the waste-acid of the German titanium dioxide industry is discharged off the Dutch coast. From March 1980 on the dumping takes place in an area situated 40–80 km from the coast. Although about 2 500 000 kg waste-acid is discharged every day, until now no effects could be found on the plankton.This paper describes the study on the effects of the dumping on the chlorophyl-a concentration of the seawater at a site north of the dumping area, with the help of time series analysis. It is shown that considerable changes in the chlorophyl concentration occur during the dumping period and that these changes coincide with certain events within the dumping history. However, it is most remarkable that the starting of the dumping itself does not show an effect on the chlorophyl concentrations. Explanations are suggested, but could not be investigated yet.This study shows also that collecting data without a proper statistical design make it impossible to draw unambiguous conclusions based on those data. 相似文献
347.
Spartina alterniflora was transplanted into dieback areas of a salt marsh in southeast Louisiana at two elevations (ambient and +30 cm) with and
without macro- (N, P, and K) and micronutrient (Fe, Mn, Cu, and Zn) additions to determine if transplant success is dependent
on increasing elevation or nutrients.Spartina alterniflora transplanted into elevated plots had more than twice the above- and belowground biomass as compared to nonelevated plots
after three months of growth. Additionally, there was significantly more vegetative reproduction (greater culm density and
number of newly produced culms) in elevated plots as compared to plots at ambient elevation. Macronutrient additions increased
culm densities only in elevated plots.Spartina alterniflora transplanted into nonelevated plots had lower survival rates even when transplants received nutrient additions. These results
suggest thatS. alterniflora may be transplanted successfully into degraded salt-marsh areas if elevation is increased. The addition of nutrients without
a concomitant increase in elevation is not sufficient for transplant success. 相似文献
348.
Section 7(a)(2) of the Endangered Species Act directs federal agencies to ensure that their actions do not jeopardize the
continued existence of endangered and threatened species. The US Fish and Wildlife Service (USFWS) issues jeopardy or nonjeopardy
biological opinions on proposed federal actions that affect endangered and threatened species. We summarize several biological
opinions issued by the USFWS to protect the threatened piping plover (Charadrius melodus). These opinions address federal actions involving hundreds of piping plovers on the Missouri River system and a few piping
plover pairs on short stretches of Atlantic coast beach. Some of these opinions are decisive, but most allow the proposed
action to proceed conditional upon a lengthy set of reasonable and prudent alternatives to protect the piping plover. These
conditions may prove difficult to track and will add to the workload of the USFWS. 相似文献
349.
This study focuses on the relationship between job stressors and mental strain in hospital work, adjusting for differences in personality traits. Questionnaires were obtained from 760 full-time employees. Fourteen scales of job stressors were clustered into four factors: professional latitude, clinical demands, workload problems and role difficulties. A mental strain index was derived from the addition of three sub-scales: depression, anxiety and irritation. Two personality traits were measured: Locus of Control (Rotter) and Striver-Achiever (Sales). The four job demand factors were dichotomized into high-low grouping variables. A 24 factorial analysis of covariance was conducted, using the two personality traits as covariates, in order to test and adjust for trait-related strain. Results show that Locus of Control adjusted differences in mental strain appear significantly related to work stressors. A direct relationship was found with role difficulties, professional latitude and workload problems. Moreover, high levels of role difficulties and low levels of professional latitude interact significantly with adjusted levels of mental strain. The Striver-Achiever trait, however, appears most strongly correlated with workload problems but not with mental strain. We believe that this exploratory analysis suggests that the stressor-strain relationship might be best conceived as a combination of direct and complex pathways, relating facets of both job demands and of personality with outcomes, under a cognitive and conditional paradigm. 相似文献
350.
R. W. P. M. Laane J. Van Der Meer A. De Vries A. Van Der Giessen 《Environmental management》1990,14(2):221-227
During the winter period an inverse linear relation is found between the concentration of dissolved nutrients (phosphorus
and nitrogen) and salinity in the Dutch coastal zone. This indicates a conservative behavior of these compounds from the river,
through the estuary to the sea. During summer this relation is much more scattered because of biological processes. The physical
and statistical properties of the relationship between salinity and the concentration of dissolved inorganic phosphorus and
nitrogen are used to calculate when, where, and how many samples have to be taken in order to monitor a reduction of a compound
accurately. It appeared that at any given salinity in the estuary and in the sea, the winter period is the most suitable season
to detect a reduction of a given dissolved compound. The higher the salinity in the estuary, the more samples are required
to prove the reduction significantly. A reduction of only 10% cannot even be demonstrated by field measurements during summer
at salinities above 25. It is concluded that one cruise from the river to the sea, covering the salinities from 0 to 35 during
the winter period, aimed at establishing the relationship between the concentration and salinity by taking samples at a salinity
interval of for instance 1%, is sufficient to monitor a wide-ranging reduction of 10%–50% in both the fresh water and marine
water. This program must be combined with a sampling at a salinity of 0, directed to determine the riverine temporal variability. 相似文献