全文获取类型
收费全文 | 2457篇 |
免费 | 33篇 |
国内免费 | 40篇 |
专业分类
安全科学 | 124篇 |
废物处理 | 155篇 |
环保管理 | 281篇 |
综合类 | 364篇 |
基础理论 | 435篇 |
环境理论 | 1篇 |
污染及防治 | 780篇 |
评价与监测 | 222篇 |
社会与环境 | 148篇 |
灾害及防治 | 20篇 |
出版年
2023年 | 33篇 |
2022年 | 71篇 |
2021年 | 88篇 |
2020年 | 43篇 |
2019年 | 44篇 |
2018年 | 94篇 |
2017年 | 94篇 |
2016年 | 118篇 |
2015年 | 78篇 |
2014年 | 107篇 |
2013年 | 242篇 |
2012年 | 147篇 |
2011年 | 184篇 |
2010年 | 128篇 |
2009年 | 111篇 |
2008年 | 150篇 |
2007年 | 123篇 |
2006年 | 143篇 |
2005年 | 113篇 |
2004年 | 74篇 |
2003年 | 51篇 |
2002年 | 49篇 |
2001年 | 29篇 |
2000年 | 12篇 |
1999年 | 18篇 |
1998年 | 10篇 |
1997年 | 9篇 |
1996年 | 12篇 |
1995年 | 14篇 |
1994年 | 10篇 |
1993年 | 9篇 |
1992年 | 12篇 |
1991年 | 6篇 |
1990年 | 14篇 |
1989年 | 9篇 |
1988年 | 8篇 |
1987年 | 5篇 |
1986年 | 5篇 |
1985年 | 5篇 |
1984年 | 8篇 |
1983年 | 3篇 |
1982年 | 4篇 |
1979年 | 4篇 |
1966年 | 4篇 |
1962年 | 2篇 |
1961年 | 2篇 |
1960年 | 3篇 |
1959年 | 2篇 |
1953年 | 2篇 |
1928年 | 2篇 |
排序方式: 共有2530条查询结果,搜索用时 15 毫秒
881.
Kostadin Ganev Maria Prodanova Dimiter Syrakov Nikolai Miloshev 《Ecological modelling》2009,217(3-4):255
US EPA Models-3 system is used for calculating the exchange of ozone pollution between three countries in southeast Europe. For the purpose, three domains with resolution 90, 30 and 10 km are chosen in such a way that the most inner domain with dimensions 90 × 147 points covers entirely Romania, Bulgaria and Greece.The ozone pollution levels are studied on the base of three indexes given in the EU Ozone Directive, mainly accumulated over threshold of 40 ppb for crops (AOT40C, period May–July), number of days with 8-h running average over 60 ppb (NOD60) and averaged daily maximum (ADM). These parameters are calculated for every scenario and the influence of each country emissions on the pollution of the region is estimated and commented.Oxidized and reduced sulphur and nitrogen loads over the territories of the three countries are also determined. The application of all scenarios gave the possibility to estimate the contribution of every country to the S and N pollution of the others and detailed blame matrixes to be build.Comparison of the ozone levels model estimates with data from the EMEP monitoring stations is made. 相似文献
882.
Within a species, ontogenetic and genetic variation in defensive chemistry can provide the basis for natural selection from
different predator types. The osmeterial chemistry of fifth (last) instar Papilio glaucus caterpillars is known to differ qualitatively from the composition of early instar caterpillars. However, the osmeterial
chemistry of early instar caterpillars has not been thoroughly characterized and may change as the caterpillars undergo their
first three molts. We have used GC/MS to identify a suite of about 50 different terpene compounds in the osmeterial secretions
of P. glaucus caterpillars, and found the relative amounts of these compounds changed significantly with each molt. These quantitative
changes preceded the more dramatic qualitative switch to the production of 2-methylbutyric and isobutyric acids after the
molt to the fifth instar. We also examined the effects of diet and genetic background on the relative quantities of 15 terpenes
present in the secretions of third instar caterpillars. Parentage was found to affect the percentages of many more of the
individual components than did diet, although both exerted an effect. The ontogenetic and genetic variations in the composition
of the osmeterial secretions appear to have an effect on would-be predators. In the laboratory, terpene secretion was found
to discourage attack by ants, whereas the switch from terpene to acid production rendered the caterpillars less palatable
to a larger predator, the green anole. In the field, the presence of functional osmeteria did not seem to dramatically increase
survival in a field study, and only a small, non-significant advantage was seen. Similarly, field data was suggestive that
parentage might affect the likelihood of survival in a natural setting, but the stage of the caterpillar and the field site
significantly affected survivorship. Further studies with greater replicates will be needed to determine whether and to what
extent chemical differences in osmeterial components as well as behavior contribute to differences in outcomes in the field. 相似文献
883.
JC Gaillard Emmanuel A. Maceda Elodie Stasiak Iwan Le Berre Maria Victoria O. Espaldon 《Journal of Coastal Conservation》2009,13(2-3):119-129
The present study investigates into the link between people’s vulnerability in the face of coastal hazards and sustainable livelihoods. It focuses on the town of Borongan in the Philippines and draws on questionnaire-based surveys and focus group discussions. This research shows that local fishermen are often compelled to go out fishing despite pending typhoon or storm surge to sustain the daily needs of their family. Its also demonstrates that the capacity of these people to protect themselves from the threat is constrained by poor and fragile livelihoods. In the event of a crisis, the study argues that people resort to a range of adjustments on their daily life which is rooted in the strength and diversity of their livelihoods. To reduce people’s vulnerability and enhance capacities to face coastal hazards, the study fosters Community-Based Disaster Risk Reduction with special emphasis to sustainable livelihoods. 相似文献
884.
Sarah Caronni Maria Anna Delaria Augusto Navone Pieraugusto Panzalis Nicola Sechi Giulia Ceccherelli 《Marine Biology》2014,161(8):1787-1798
Chrysophaeum taylorii (Pelagophyceae) is an allochthonous benthic microalga recently recorded in the Mediterranean Sea. During summer, the occurrence of C. taylorii is usually visible to the naked eye due to the large amount of mucilage this species produces. Information on the spatio-temporal variability of this species and on the predictability of massive mucilage events is still scarce and requires to define ad hoc managing strategies of major bloom events. The aim of this work was to identify the relevant scales of variation in the abundance of C. taylorii abundance and to estimate the relative recurrence of its blooms, testing the hypothesis that mucilage was dependent on the cell density. The first approach was the identification of the most appropriate sampling procedure to estimate benthic cell abundance of C. taylorii. The second one was the estimation of the magnitude of variation in C. taylorii cell abundance attributable to each of several spatial (areas, sites, zones and replicates) and temporal scales (fortnights and years) in the Marine Protected Area of Tavolara Punta Coda Cavallo (Western Mediterranean Sea). The results indicate fortnight and year as the most relevant scales of variability in the cell abundance of C. taylorii and highlight the unimportance of small spatial scales (zone and replicates) to the species variability. The collected data also evidence the absence of a direct relationship between the cell density of C. taylorii and the production of mucilage. In conclusion, these results indicate that patterns in the cell abundance of C. taylorii vary notably depending on the considered scale and that future investigations on processes affecting its performance will need to consider the relevant scales of variation evidenced. 相似文献
885.
Filial cannibalism in a nest-guarding fish: females prefer to spawn in nests with few eggs over many
In fish, fecundity correlates with female body size and egg-tending males often eat small broods. Therefore, small females may prefer to spawn in nests that already contain many eggs, to ensure the brood is as large as possible. In contrast, large females may prefer nests with few eggs, if high egg number or density has a negative effect on egg survival, or if there are drawbacks of spawning last in a nest. To test the hypothesis that female body size affects nest (and male mate) choice, using the sand goby (Pomatoschistus minutus), we allowed small and large females to choose between two males that were matched in size — one guarding a small clutch and the other a large clutch, respectively. We recorded where females spawned (measure of female preference), the combined brood size, male courtship, egg care and nest building. We also quantified the effect of brood size and egg density on egg survival in a separate data set. Although the combined broods did not exceed the small brood sizes that are at risk of being eaten, both small and large females preferred to spawn in nests with smaller clutch sizes. This preference could not be explained by more courtship or male parental effort, nor by reduced survival of larger or denser broods. Instead, our result might be explained by females avoiding the danger of cannibalism of young eggs by males or the risk of reduced egg health associated with being near the nest periphery. 相似文献
886.
Häring Ivo Fehling-Kaschek Mirjam Miller Natalie Faist Katja Ganter Sebastian Srivastava Kushal Jain Aishvarya Kumar Fischer Georg Fischer Kai Finger Jörg Stolz Alexander Leismann Tobias Hiermaier Stefan Carli Marco Battisti Federica Makri Rodoula Celozzi Giuseppe Belesioti Maria Sfakianakis Evangelos Agrafioti Evita Chalkidou Anastasia Papadakis George Fuggini Clemente Bolletta Fabio Neri Alberto Giunta Guiseppe Scheithauer Hermann Höflinger Fabian Schott Dominik J. Schindelhauer Christian Köhler Sven Linkov Igor 《The Environmentalist》2021,41(2):286-329
Environment Systems and Decisions - Organizational and technical approaches have proven successful in increasing the performance and preventing risks at socio-technical systems at all scales.... 相似文献
887.
Marina M. S. Cabral Pinto A. Paula Marinho-Reis Agostinho Almeida Carlos M. Ordens Maria M. V. G. Silva Sandra Freitas Mário R. Simões Paula I. Moreira Pedro A. Dinis M. Luísa Diniz Eduardo A. Ferreira da Silva M. Teresa Condesso de Melo 《Environmental geochemistry and health》2018,40(5):1767-1784
New lines of evidence suggest that less than 10% of neurodegenerative diseases have a strict genetic aetiology and other factors may be prevalent. Environmental exposures to potentially toxic elements appear to be a risk factor for Parkinson’s, Alzheimer’s and sclerosis diseases. This study proposes a multidisciplinary approach combining neurosciences, psychology and environmental sciences while integrating socio-economic, neuropsychological, environmental and health data. We present the preliminary results of a neuropsychological assessment carried out in elderly residents of the industrial city of Estarreja. A battery of cognitive tests and a personal questionnaire were administered to the participants. Multivariate analysis and multiple linear regression analysis were used to identify potential relationships between the cognitive status of the participants and environmental exposure to potentially toxic elements. The results suggest a relationship between urinary PTEs levels and the incidence of cognitive disorders. They also point towards water consumption habits and profession as relevant factors of exposure. Linear regression models show that aluminium (R 2 = 38%), cadmium (R 2 = 11%) and zinc (R 2 = 6%) are good predictors of the scores of the Mini-Mental State Examination cognitive test. Median contents (µg/l) in groundwater are above admissible levels for drinking water for aluminium (371), iron (860), manganese (250), and zinc (305). While the World Health Organization does not provide health-based reference values for aluminium, results obtained from this study suggest that it may have an important role in the cognitive status of the elderly. Urine proved to be a suitable biomarker of exposure both to elements with low and high excretion rates. 相似文献
888.
Maria D. Kamitsou Varvara Sygouni Dimitra G. Kanellopoulou Konstantinos Gardikis Petros G. Koutsoukos 《Environmental geochemistry and health》2018,40(4):1449-1464
Clays and muds have been used for centuries as cosmetics or pharmaceutical products for various therapies. The suitability of muds and clays for health- and beauty-related applications depends on their physicochemical properties, mineralogical composition, particle characteristics and toxicity. In this work, the physicochemical characterization of 12 mud specimens from different natural spa resorts in Greece and one from Israel (Dead Sea) is presented. All specimens were sterilized at 121 °C for 20 min, because of their intended use. The Greek mud specimens were collected from various locations in Macedonia, Western Greece and Northeast Aegean. All muds were characterized concerning their mineralogical, chemical components as well as their morphological characteristics using appropriate methods [powder X-ray diffraction (XRD), thermogravimetric analysis (TGA), nitrogen absorption specific surface area measurements (BET), scanning electron microscopy and energy dispersive X-ray spectroscopy]. The concentrations of F?, Cl?, NO3? and SO42? anions at equilibrium with the mud specimens were measured by ion chromatography. Total calcium concentration was measured using atomic absorption spectroscopy, and the concentration of total N, C, H and S in the solids was measured using elemental analysis. Moreover, total phenolic concentration (TPC) in distilled water equilibrated with the mud specimens was measured as an index for their antioxidant properties. Several muds were found to present high TPC. Several of the examined mud specimens were found to have the potential use as pharmaceuticals or cosmetics. Based on the physicochemical characteristics of the mud specimens examined, possible improvement in their use and applicability has been suggested. 相似文献
889.
Gritta Veit-Köhler Marleen De Troch Mateja Grego Tania Nara Bezerra Wendy Bonne Guy De Smet Christina Folkers Kai Horst George Chen Guotong Rudy Herman Rony Huys Nikolaos Lampadariou Jürgen Laudien Pedro Martínez Arbizu Armin Rose Michaela Schratzberger Sybille Seifried Paul Somerfield Jan Vanaverbeke Edward Vanden Berghe Magda Vincx Borut Vriser Leen Vandepitte 《Marine Biology》2010,157(8):1819-1835
A large-scale database concerning benthic copepods from the Arctic, Baltic Sea, North Sea, British Isles, Adriatic Sea and Crete was compiled to assess species richness, biodiversity, communities, ecological range size and biogeographical patterns. The Adriatic showed the highest evenness and the most species-rich communities. Assemblages from the North Sea, British Isles, Baltic and Crete had a lower evenness. The British Isles were characterised by impoverished communities. The ecological specificity of copepod species showed two diverging trends: higher specificity of species in more diverse assemblages was observed in the Adriatic, North Sea and Baltic. A uniformly high species specificity disregarding sample diversity was found on Crete and in the British Isles. Benthic copepod communities showed distinct patterns that clearly fit the predefined geographical regions. Communities were distinguishable and β-diversity was found to be high around Europe, indicating a high species turnover on the scale of this investigation. The British Isles and the North Sea were found to be faunistic links to the Baltic and the Arctic. 相似文献
890.
Maria Byrne Natalie A. Soars Melanie A. Ho Eunice Wong David McElroy Paulina Selvakumaraswamy Symon A. Dworjanyn Andrew R. Davis 《Marine Biology》2010,157(9):2061-2069
Climate change driven ocean acidification and hypercapnia may have a negative impact on fertilization in marine organisms
because of the narcotic effect these stressors exert on sperm. In contrast, warmer, less viscous water may have a positive
influence on sperm swimming speed and so ocean warming may enhance fertilization. To address questions on future vulnerabilities
we examined the interactive effects of near-future ocean warming and ocean acidification/hypercapnia on fertilization in intertidal
and shallow subtidal echinoids (Heliocidaris erythrogramma, H. tuberculata, Tripneustes gratilla, Centrostephanus rodgersii), an asteroid (Patiriella regularis) and an abalone (Haliotis coccoradiata). Batches of eggs from multiple females were fertilized by sperm from multiple males in all combinations of three temperature
and three
\textpH/P\textCO2 {\text{pH}}/P_{{{\text{CO}}_{2} }} treatments. Experiments were placed in the setting of projected near-future conditions for southeast Australia, an ocean
change hot spot. There was no significant effect of warming and acidification on the percentage of fertilization. These results
indicate that fertilization in these species is robust to temperature and
\textpH/P\textCO2 {\text{pH}}/P_{{{\text{CO}}_{2} }} fluctuation. This may reflect adaptation to the marked fluctuation in temperature and pH that characterises their shallow
water coastal habitats. Efforts to identify potential impacts of ocean change to the life histories of coastal marine invertebrates
are best to focus on more vulnerable embryonic and larval stages because of their long time in the water column where seawater
chemistry and temperature have a major impact on development. 相似文献