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141.
Climate change, ambient ozone, and health in 50 US cities 总被引:2,自引:1,他引:2
Michelle L. Bell Richard Goldberg Christian Hogrefe Patrick L. Kinney Kim Knowlton Barry Lynn Joyce Rosenthal Cynthia Rosenzweig Jonathan A. Patz 《Climatic change》2007,82(1-2):61-76
We investigated how climate change could affect ambient ozone concentrations and the subsequent human health impacts. Hourly
concentrations were estimated for 50 eastern US cities for five representative summers each in the 1990s and 2050s, reflecting
current and projected future climates, respectively. Estimates of future concentrations were based on the IPCC A2 scenario
using global climate, regional climate, and regional air quality models. This work does not explore the effects of future
changes in anthropogenic emissions, but isolates the impact of altered climate on ozone and health. The cities’ ozone levels
are estimated to increase under predicted future climatic conditions, with the largest increases in cities with present-day
high pollution. On average across the 50 cities, the summertime daily 1-h maximum increased 4.8 ppb, with the largest increase
at 9.6 ppb. The average number of days/summer exceeding the 8-h regulatory standard increased 68%. Elevated ozone levels correspond
to approximately a 0.11% to 0.27% increase in daily total mortality. While actual future ozone concentrations depend on climate
and other influences such as changes in emissions of anthropogenic precursors, the results presented here indicate that with
other factors constant, climate change could detrimentally affect air quality and thereby harm human health. 相似文献
142.
As the primordial, prokaryotic inhabitants on Earth, microbial entities were responsible for significant influences on the pathways taken in the development of life as we know it. The manifestation of numerous pathologies in humans is considered to be intrinsically associated with microbial dysbiosis in the gut(i.e. a poorly balanced microbiota). Such adverse health conditions include obesity, chronic fatigue syndrome, cancer, cardiovascular issues, neurological disorders, colitis, irritable bowel syndrome(IBS), and rheumatoid arthritis. Endosymbiotic events at the single cell level took place billions of years ago, eventually leading to eukaryotes, photosynthesis, and multicellularity. Macroalgae(seaweeds) were amongst the first organisms to develop these characteristics. Microbes and macroalgae interacted in a pattern of co-evolution,a process that applies to most, if not all living organisms. It is recognized that the normal human microbiome consists of over a trillion microorganisms, including about 2 000 commensal bacterial species typically stationed in the gut. Many of these live in the colon, where they function in the digestion of foods, releasing bio-available nutrients, bioactive molecules, and various metabolites. They mediate communication signals between the gut and the brain, and promote the normal development of immune function, metabolic activities, behaviour, and neurological stability. As very early humans foraged for food, some would have benefitted from coastal diets, rich in seaweeds and associated microbes. Such diets would have consistently provided all the nutrients essential for survival and growth, and as such, could have conveyed competitive advantages and contributed to enhanced cognitive sophistication. This mini-review article highlights studies regarding the health benefits of dietary fibres and the production of short chain fatty acids(SCFA). Insights are offered regarding the positive effects the inclusion of macroalgae into the standard, Western diet can deliver in terms of providing appropriate fodder for those microbial populations deemed beneficial to human health and wellness. 相似文献
143.
As the primordial,prokaryotic inhabitants on Earth,microbial entities were responsible for significant influences on the pathways taken in the development of life as we know it.The manifestation of numerous pathologies in humans is considered to be intrinsically associated with microbial dysbiosis in the gut(i.e.a poorly balanced microbiota).Such adverse health conditions include obesity,chronic fatigue syndrome,cancer,cardiovascular issues,neurological disorders,colitis,irritable bowel syndrome(IBS),and rheumatoid arthritis.Endosymbiotic events at the single cell level took place billions of years ago,eventually leading to eukaryotes,photosynthesis,and multicellularity.Macroalgae(seaweeds)were amongst the first organisms to develop these characteristics.Microbes and macroalgae interacted in a pattern of co-evolution,a process that applies to most,if not all living organisms.It is recognized that the normal human microbiome consists of over a trillion microorganisms,including about 2000 commensal bacterial species typically stationed in the gut.Many of these live in the colon,where they function in the digestion of foods,releasing bio-available nutrients,bioactive molecules,and various metabolites.They mediate communication signals between the gut and the brain,and promote the normal development of immune function,metabolic activities,behaviour,and neurological stability.As very early humans foraged for food,some would have benefi tted from coastal diets,rich in seaweeds and associated microbes.Such diets would have consistently provided all the nutrients essential for survival and growth,and as such,could have conveyed competitive advantages and contributed to enhanced cognitive sophistication.This mini-review article highlights studies regarding the health benefits of dietary fibres and the production of short chain fatty acids(SCFA).Insights are off ered regarding the positive effects the inclusion of macroalgae into the standard,Western diet can deliver in terms of providing appropriate fodder for those microbial populations deemed beneficial to human health and wellness. 相似文献
144.
Lynn Abramson Sue Wirick Cindy Lee Chris Jacobsen Jay A. Brandes 《Deep Sea Research Part II: Topical Studies in Oceanography》2009,56(18):1369-1380
Diatoms play a significant role in the global carbon cycle through their role in biogenic silica production and the transport of organic matter to the seafloor. Recent work has shown that silicified diatom frustules contain a significant amount of organic matter, and that the proportion of diatom-bound organic matter increases with depth in the water column and sediments. Here, we investigate the association between organic matter and the mineral phase. We used a combination of scanning transmission X-ray microscopy (STXM) and carbon X-ray absorption near-edge structure (XANES) spectroscopy to characterize the distribution and composition of organic matter in frustules of the diatom Cylindrotheca closterium and a biomimetic silica gel. To our knowledge, this study represents the first successful attempt to simultaneously image and obtain chemical information about the organic matter within a diatom frustule using X-ray spectromicroscopy near the carbon edge. Organic carbon, most likely protein, was distributed throughout the frustules and was not removed by harsh chemical treatment. The physical structure of the frustules appeared to be related to the chemical composition of this organic matter, with aromatic or unsaturated carbon being concentrated in the most intricately patterned regions of the frustule. A similar physical and chemical structure was observed in a biomimetic silica gel precipitated spontaneously with polylysine. These results are consistent with the theory that organic constituents of diatom frustules direct silica precipitation and become incorporated within the silica matrix as it forms. The relationship between organic matter composition and silica morphology, the failure of harsh chemical treatments to remove this organic matter, and the spontaneous nature of the co-precipitation of silica and organic matter indicate some chemical interaction between the siliceous and organic components of diatom frustules. Frustule-bound organic matter should therefore be protected from decomposition in the water column or diagenetic alteration in sediments unless the frustule dissolves. 相似文献
145.
AbstractLiterature on environment-related outcomes highlights the role of political and religious factors—in particular, political orientation, party affiliation and biblical beliefs. Less is known about how these factors independently and interactively shape attitudes towards policy and environmental behaviors including how political factors may be moderated by religious beliefs. Using structural equation modeling and data from the 2010 GSS, we find that in the United States political orientation and party affiliation independently affect willingness to pay for the environment and to engage in pro-environmental behaviors. Biblical beliefs have no effect on behaviors, but strongly influence willingness to pay. Moreover, biblical beliefs moderate the effects of political orientation: the more politically conservative biblical literalist are the more willing they are willing to pay for the environment. We conclude with a discussion of these surprising results by calling for more intersectional approaches to environment-related behaviors and attitudes. 相似文献
146.
147.
Research has been conducted to evaluate if electrophoresis could transport surface stabilized nanoscale zero-valent iron (nZVI) through fine grained sand with the intent of remediating a contaminant in situ. The experimental procedure involved determining the transport rates of polymer modified nZVI and hematite in fine grained sands under an applied electrical gradient under different physical and chemical conditions. Results indicated transport of polymer modified nZVI and hematite can be accomplished by electrophoresis, with rates found to be much higher than diffusion alone and comparable to those predicted by electrokinetic theory. This study indicates there is potential for this method to deliver polymer modified nZVI into contaminated zones within fine grained sands for the purpose of remediation. 相似文献
148.
Three anthropogenic sources (urban, soil, and industrial runoff) were characterized for bulk nutrient and dissolved organic matter (DOM) composition using wet chemistry and Fourier transform ion cyclotron resonance mass spectrometry. Each source was unique based on its chemical composition. Dissolved inorganic nitrogen (N) comprised 91, 60, and 20 % of the total N pool in the soil, urban, and industrial sources, respectively. The DOM composition was dominated by terrestrial compounds in the soil, condensed hydrocarbons, lipids and proteins in the urban, and lipid-like compounds in the industrial source. A York River (VA) phytoplankton assemblage, dominated by Cochlodinium polykrikoides, was amended with the sources during a 7-day bioassay. There was a doubling of chlorophyll a and/or cell concentrations within 2 days, in the +Urban and +Soil treatments. The + Industrial treatment supported algal growth, but increases in cell abundances were only statistically significant at the end of the experiment (days 5–7), suggesting that this material was less labile to the original York River community than the other anthropogenic nutrient sources, on the relatively short timescale of the study. 相似文献
149.
B. B. Lynn F. P. Keenan P. L. Dufton W. R. J. Rolleston J. V. Smoker R. S. I. Ryans D. Kilkenny D. O'Donoghue N. Hambly H. T. McGillivray 《Monthly notices of the Royal Astronomical Society》2005,363(3):911-917
High spectral resolution ( R ∼ 40 000) and signal-to-noise optical spectra, obtained at the Very Large Telescope (VLT), are presented for three post–asymptotic giant branch (AGB) candidates selected from the Edinburgh–Cape (EC) Faint Blue Object Survey. The stellar atmospheric parameters and chemical compositions, derived using sophisticated non-local thermodynamic equilibrium calculations, reveal that EC 14102-1337 and EC 20068-7324 are both in an evolved post–horizontal branch (HB) evolutionary state. However, EC 11507-2253 is most likely a post-AGB star. 相似文献