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排序方式: 共有173条查询结果,搜索用时 15 毫秒
61.
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Inga Wobker Peter Kenning Marco Lehmann-Waffenschmidt Gerd Gigerenzer 《Journal für Verbraucherschutz und Lebensmittelsicherheit》2014,9(3):231-242
This research investigates Minimal Economic Knowledge (MEK) of consumers in Germany—that is, basic economic knowledge needed for understanding and successfully participating in the economy. First we develop a scale for measuring MEK in four economic domains: finance, labour economics, consumption, and public economics, testing for three kinds of knowledge within each domain, namely facts, concepts, and causal relationships. Second, we conduct an empirical study to test MEK level and influence of demographic drivers in a representative sample of German adult consumers (N = 1,314), with a mean result of only 59.4 points (of 100), indicating a considerable lack of even minimal economic knowledge. And third, using a subsample, we study factors that result in differences in the level of MEK showing among others that the choice of “sensationalist” versus “serious” news sources, both on television and in newspapers, is associated with a loss of about 10 MEK points, while, surprisingly, participating in an economics course did not enhance minimal economic knowledge. The article closes with a discussion of implications for consumer policy-making. 相似文献
63.
Effect of sorbate planarity on environmental black carbon sorption 总被引:11,自引:0,他引:11
Cornelissen G Elmquist M Groth I Gustafsson O 《Environmental science & technology》2004,38(13):3574-3580
Soot and charcoal, collectively termed "black carbon" or BC, can exhibit extremely strong sorption of many hydrophobic organic compounds. In order to include BC sorption in fate models, it is important to know BC nanopore surface areas. In addition, it is useful to know for which compounds BC sorption can be expected to be important. By nitrogen adsorption measurements at ultralow pressures on sediment that was strongly enriched in BC by HF treatment and/or chemothermal oxidation at 375 degrees C, we found that environmental BC has nanoporosity in the <4-10 A size range. The nanopore surface area (<50 A) of BC in Lake Ketelmeer (The Netherlands) sediment was approximately 58 m2/g. We measured sorption isotherms over a wide concentration interval for four compounds with the same Kow (10(46+/-0.1): planar anthracene (ANT), phenanthrene (PHE), and 4-chlorobiphenyl (4-PCB) along with nonplanar 2,2'-dichlorobiphenyl (2,2'-PCB). The environmental BC sorption coefficients of these iso-Kow compounds decreased in the order ANT > PHE approximately 4-PCB > 2,2'-PCB and spanned a factor of 50-200, depending on concentration. Nonplanar 2,2'-PCB showed much more linear BC sorption (nF = 0.92) than the planar compounds (nF = 0.54-0.70). This shows that steric hindrance strongly attenuates BC-sorbate interactions for a nonplanar PCB. Thus, BC is more important for environmental sorption of planar compounds (>50% sorbed to BC in the nanogram per liter range) than for nonplanar ones (<10-20%). Using the measured BC nanopore surface area, a close agreement between modeled and measured BC sorption data could be found. 相似文献
64.
Nguyen Phan Khoi Le Corinna Herz Joo Victor Dutra Gomes Nadja Frster Kyriaki Antoniadou Verena Karolin Mittermeier-Kleßinger Inga Mewis Corinna Dawid Christian Ulrichs Evelyn Lamy 《International journal of molecular sciences》2021,22(13)
The usefulness of anti-inflammatory drugs as an adjunct therapy to improve outcomes in COVID-19 patients is intensely discussed in this paper. Willow bark (Salix cortex) has been used for centuries to relieve pain, inflammation, and fever. Its main active ingredient, salicin, is metabolized in the human body into salicylic acid, the precursor of the commonly used pain drug acetylsalicylic acid (ASA). Here, we report on the in vitro anti-inflammatory efficacy of two methanolic Salix extracts, standardized to phenolic compounds, in comparison to ASA in the context of a SARS-CoV-2 peptide challenge. Using SARS-CoV-2 peptide/IL-1β- or LPS-activated human PBMCs and an inflammatory intestinal Caco-2/HT29-MTX co-culture, Salix extracts, and ASA concentration-dependently suppressed prostaglandin E2 (PGE2), a principal mediator of inflammation. The inhibition of COX-2 enzyme activity, but not protein expression was observed for ASA and one Salix extract. In activated PBMCs, the suppression of relevant cytokines (i.e., IL-6, IL-1β, and IL-10) was seen for both Salix extracts. The anti-inflammatory capacity of Salix extracts was still retained after transepithelial passage and liver cell metabolism in an advanced co-culture model system consisting of intestinal Caco-2/HT29-MTX cells and differentiated hepatocyte-like HepaRG cells. Taken together, our in vitro data suggest that Salix extracts might present an additional anti-inflammatory treatment option in the context of SARS-CoV-2 peptides challenge; however, more confirmatory data are needed. 相似文献
65.
Inga Klavina Tiit KaljuveeKristi Timmo Jaan RaudojaRainer Traksmaa Mare AltosaarDieter Meissner 《Thin solid films》2011,519(21):7399-7402
The present study deals with the possible chemical interactions of CuSe, SnSe, and ZnSe in molten KI as a flux material in vacuum ampoules. The aim is to find suitable preparation conditions for the synthesis of Cu2ZnSnSe4 monograin powders as an absorber material for solar cells. Impurities in the precursor materials and in the product powders were determined by inductively coupled plasma mass spectrometry. Differential thermal analysis was used to determine thermal effects. Phase composition in the mixtures of binary precursors and KI was determined by X-ray diffraction and Raman spectroscopy. It was found that no new compound was formed in the CuSe/KI, ZnSe/KI and SnSe/KI mixtures. The solubility of the binary chalcogenides in KI at 740 °C was determined. 相似文献
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69.
Gudrun Schmidt-Naake Anne Schmalfuß Inga Woecht 《Chemical Engineering Research and Design》2008,86(7):765-6
The influence of the ionic liquid (IL) 1-ethyl-3-methylimidazoliumethylsulfate ([EMIM]EtSO4) on the polymerization kinetics of methyl methacrylate was investigated. ILs are liquids with relatively high polarities and viscosities. These two characteristic properties are strongly correlated with the rate coefficients of propagation kp and termination kt of polymerizations carried out in ILs. The rate constant of termination kt decreases when the concentration of ionic liquid, and thus the viscosity is increased, whereas the propagation rate coefficient kp increases with increasing IL content. The viscosity of ILs can be varied by either working with mixtures of ILs with conventional organic solvents – here the IL [EMIM]EtSO4 was mixed with dimethyl formamide (DMF) – or by variation of the temperature. The studies were carried out to determine the influence of the viscosity on the propagation and the termination reaction as well as the molecular weight distribution. 相似文献
70.
Barton SJ Richardson S Perkins DN Bellahn I Bryant TN Whittaker JC 《Analytical chemistry》2007,79(15):5601-5607
A database of 5448 peptide tandem mass spectra acquired in a quadrupole time-of-flight mass spectrometer was generated for peptides derived from proteins digested with trypsin. Peptides were identified from their mass spectra by the Mascot algorithm. Statistical models were then used to investigate factors influencing the abundance of ions formed. Separate models were formulated for b and y ions as it was thought that different factors may influence the formation of each type of ion. Several factors were found to have a highly significant influence on the abundance of ions formed. These include the actual mass of the ion formed after fragmentation as well as the location of the cleavage. The composition of the fragmenting peptide was also found to be important, and amino acids either side of the fragmentation site influenced the abundance of ions produced. To increase understanding of fragmentation mechanisms, the effect of several physicochemical properties of these residues was also investigated in a separate model. In conclusion, the models formulated for b and y ions provide useful characterization of the abundance of ions formed, and this information could be used to develop improved algorithms for peptide identification. 相似文献