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41.
This paper aims at studying the effect of the colors of e-commerce websites on consumer mood, memorization and buying intention. On the basis of a literature review a conceptual model is proposed, showing the effects of the color of e-commerce websites and specifically of its components, hue and brightness on the behavioral responses of the consumer, memorization and buying intention. These responses are conveyed by mood. Data collection was carried out during a laboratory experiment in order to control for the measurement of the colored appearance of e-commerce websites. Participants visited one of the eight versions of a website designed for the research, selling music CDs. Data analysis using ANOVA, regressions and general linear models show a significant effect of color on memorization, conveyed by mood. The interaction of hue and brightness, using chromatic colors for the background and foreground supports memorization and buying intention, when contrast is based on low brightness. A negative mood infers better memorization but a decreasing buying intention. Implications for theory and practice are discussed.  相似文献   
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The adsorption of thiram and disulfiram onto alpha-Al2O3 and montmorillonite clay has been studied in the presence of small carboxylate anions, bicarbonate, formate, and oxalate. At natural concentrations, HCO3- enhances dramatically the adsorption of both pesticides on alpha-Al2O3 and clay. An analogous significant enhancement of pesticide adsorption is also observed in the presence of formate and oxalate. Density functional theory calculations demonstrate that in solution a stable molecular complex between one molecule of thiram and one molecule of HCO3- is formed with interaction energy -35.6 kcal/mol. In addition, two H20 molecules further stabilize it by an interaction energy of -3.6 kcal/mol. This clustering [thiram- HCO3- -2H2O] leads to a change of the electronic structure and the ultraviolet-visible spectrum of thiram that is observed experimentally. Surface complexation modeling shows that the molecular cluster [thiram-HCO3- -2H2O], which bears a total net charge of -1, is responsible for the observed enhanced adsorption on the charged surface of alumina and clay at pH below their points of zero surface charge. The results reveal a novel pervasive role of carboxylate anions and particularly HCO3- on the adsorption of dithiocarbamate pesticides in natural waters.  相似文献   
43.
A high performance liquid chromatography with a diode-array detector (HPLC-DAD) and a gas chromatography with a mass spectrometer (GC-MSD) are described for the determination of patulin (PAT) in apple juice. The limits of detection (DL) and quantification (QL) for the HPLC-DAD and GC-MSD method were found to be (DL = 0.23 μg kg−1 QL = 1.2 μg kg−1) and (DL = 5.8 μg kg−1 and QL = 13.8 μg kg−1), respectively. The recovery factors for HPLC-DAD and GC-MSD were found to be 99.5% (RSD% = 0.73) and 41% (RSD% = 10.03), respectively. The HPLC-DAD method was used to determine the occurrence of PAT in 90 samples of fruit juices.  相似文献   
44.
Migration levels of commercial plasticisers [di-(2-ethylhexyl) adipate (DEHA) and acetyl tributyl citrate (ATBC)] from polyvinyl chloride (PVC) film into the EU specified aqueous food simulants (distilled water, 3% w/v acetic acid and 10% v/v ethanol) were monitored as a function of time. Migration testing was carried out at 40 °C for 10 days (EEC, 1993). Determination of the analytes was performed by applying the analytical methodology based on surfactant (Triton X-114) mediated extraction prior to gas chromatographic-flame ionisation detection (GC-FID) recently proposed by our group. The study focuses on the determination of the effect of gamma radiation on plasticiser migration into the selected simulants. PVC cling film used was subjected to ionising treatment with a [60Co] source at doses equal to 5, 15 and 25 kGy. DEHA and ATBC migration into the EU aqueous simulating solvents was limited, yielding final concentrations in the respective ranges 10–100 μg/l and 171–422 μg/l; hence, ATBC demonstrated a stronger interaction with all three simulants compared to DEHA. Migration data, with respect to ATBC, showed that the most aggressive simulant seemed to be the 10% ethanol, while in the case of DEHA the 3% aqueous acetic acid exhibited the highest extraction efficiency; distilled water demonstrated the lowest migration in both cases. With regard to PVC treatment with gamma rays, high radiation doses up to 25 kGy produced a statistically significant (< 0.05) effect on the migration of both plasticisers.  相似文献   
45.
CD24 is a cell-surface protein mainly expressed in cells of the immune and central nervous system (CNS), cells that play a critical role in the development of multiple sclerosis (MS). In the current study, we investigated four polymorphisms of the CD24 gene regarding their associations with MS. To this end, univariate and multivariate meta-analysis were applied along with modifications to include data from family-trios so as to increase the robustness of the meta-analysis. We found that the polymorphism 226 C>T (Ala57Val) of the CD24 gene is associated with MS according to the recessive mode of inheritance (odds ratio = 1.75; 95% CI: 1.09, 2.81). Moreover, the 1527–1528 TG>del polymorphism is inversely associated with MS according to the dominant mode of inheritance (odds ratio = 0.57; 95% CI 0.39, 0.83). Conversely, the 1056 A>G and 1626 A>G polymorphisms were not found to be associated with MS. We conclude that the CD24 226 C>T polymorphism increases the risk of MS, while the 1527–1528 TG>del polymorphism seems to have a protective role against MS, suggesting that these two polymorphisms can be used as predictive biomarkers for MS development.  相似文献   
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The air/biopolymer partition coefficient (K) and percentage of retention (R%) of ethyl butyrate (400 ppm) added to gellan gels were determined, using static headspace gas chromatography. Potassium chloride (40–120 mM) was used to induce gellan gelation. When 5 g of sample were left to equilibrate at 37 °C for 2 and 24 h, the coefficient values initially decreased with salt concentration to a certain value after which they raised again. The lower coefficient values, for the 24 h period, were observed at higher salt concentration than for the 2 h. Moreover, for both time periods, the lower coefficient values were found for the gellan gels with the greater strength and rigidity and were accompanied by positive percentages of retention. When 15 g of sample were used, after equilibration at 37 °C for 24 h, no significant changes in aroma release were observed. Moreover, negative percentages of retention values were calculated for all salt concentrations.  相似文献   
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The two crucial cellular insults that take place during cerebral ischemia are the loss of oxygen and loss of glucose, which can both activate a cascade of events leading to neuronal death. In addition, the toxic overactivation of neuronal excitatory receptors, leading to Ca2+ overload, may contribute to ischemic neuronal injury. Brain ischemia can be simulated in vitro by oxygen/glucose deprivation, which can be reversible by the re-establishment of physiological conditions. Accordingly, we examined the effects of glucose deprivation on the PI3K/Akt survival signaling pathway and its crosstalk with HIF-1α and Ca2+ homeostasis in SH-SY5Y human neuroblastoma cells. It was found that glucose withdrawal decreased HIF-1α protein levels even in the presence of the ischemia-mimicking CoCl2. On the contrary, and despite neuronal death, we identified a strong activation of the master pro-survival kinase Akt, a finding that was also confirmed by the increased phosphorylation of GSK3, a direct target of p-Akt. Remarkably, the elevated Ca2+ influx recorded was found to promptly trigger the activation of Akt, while a re-addition of glucose resulted in rapid restoration of both Ca2+ entry and p-Akt levels, highlighting the plasticity of neurons to respond to ischemic challenges and the important role of glucose homeostasis for multiple neurological disorders.  相似文献   
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