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41.
Imogen Stewart 《Costume》2013,47(1):120-127
Abstract

This list includes temporary exhibitions and new permanent displays mounted in UK museums and galleries during 2012. Each display contained at least some items of dress or dress fabrics, fashion plates or fashion photography.  相似文献   
42.
A high performance liquid chromatography method with evaporative light scattering detection was developed for the analysis of oils and fats, which enabled excellent separation of major and minor triacylglycerol (TAG) species in 33 min, including regeneration of the column. The influence of the mobile phase and temperature on separation and analysis time were evaluated with a cocoa butter standard. The influence of the drift tube temperature and flow of the nebulising gas on the evaporative light scattering detector output signal was investigated by means of a response surface experimental design. Especially the flow of the nebulising gas had a profound effect on the detector signal. An optimal separation was obtained when using a 150 × 3.0 mm C18 column with 3 μm particle diameter at 20 °C and an acetonitrile/dichloromethane gradient at 0.72 mL/min. The maximum response was attained when the ELSD detector was set at the minimum temperature (45 °C) and a gas flow of 1.2 L/min. Finally, the linearity of the detector was investigated. It was found that at very low concentrations, the signal tends to flatten towards zero, giving an underestimation for minor TAG species, especially for oils or fats with a mixed fatty acid composition.  相似文献   
43.
The impulse response time has been measured as a function of reverse bias, gain, and temperature in backside-illuminated short-wave infrared HgCdTe avalanche photodiodes (APDs) with variable junction geometry. The APD geometry was altered using HgCdTe substrates of variable thickness and by variation of device fabrication parameters. This approach allowed study of the drift–diffusion dynamics of the electrons before entering the junction and the electron and hole dynamics during the junction transition in APDs with different carrier collection distances and junction widths. The response time was typically limited by a double exponential decay, which is attributed to contributions from the impedance mismatch between the interconnection circuit and the 50-Ω radiofrequency probe, and a delayed diffusion response from carriers generated far from the junction. These contributions limited the maximum bandwidth of the diodes to about 600 MHz, independently of gain and temperature. The hot carrier velocities are estimated by fitting the measured response with numerical calculations, taking into account contributions from a direct drift–multiplication response and a delayed diffusion response. This analysis shows that the hot carrier dynamics is close to independent of temperature and that the electron drift velocity saturates at the gain onset to a value of 1 × 107 cm/s, decreasing upon a further increase of the electric field E to a value of about 3 × 106 cm/s at E = 100 kV/cm. The hole velocity shows a slow variation from 3 × 106 cm/s at low electric fields to 1.5 × 106 cm/s at high electric fields.  相似文献   
44.
45.
This study investigated the possibility that, in remitted bipolar I affective disorder, dysfunctional attitudes are mood-state dependent. Participants were 120 individuals with remitted bipolar I disorder, remitted unipolar depression, or no history of affective disorder. The Dysfunctional Attitudes Scale (DAS; Weissman, 1979) was completed before and after positive or negative mood challenge. Following mood increase, the bipolar group changed significantly less in DAS total score than did the other 2 groups, and in goal-striving and achievement attitudes relative to the unipolar group. These findings did not provide clear support for the mood-state dependency theory in bipolar disorder, arguing instead for the presence in bipolar I disorder of dysfunctional cognitions that show characteristic resilience in the face of minor positive mood increase. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
46.
As are traditional fractionation technologies, static dry fractionation is a highly reliable technology for the consistent production of good-quality palm kernel stearin (PKS) for use as cocoa butter substitute (CBS) after total hydrogenation. A new process route now permits the production of unhardened yet high-quality CBS. Also an increase in total stearin yield can be achieved, via a successful refractionation of palm kernel olein. DSC analysis together with pilot static fractionation trials on the palm kernel olein indicates that a cooling water temperature that is too low (e.g., 17°C) may result in the quick formation of unstable crystals that are possibly later converted to a more stable form. The resulting mixture of crystals with a possibly different polymorphic structure is easily squeezed through the filter cloth during filtration, whereas a slower, but more homogeneous co-crystallization occurs at higher temperature (18°C or higher) and results in a much more stress-resistant slurry. Polarized light microscopy analysis confirmed that crystal size is not the only determining factor for a successful filtration. The total two-stage static fractionation of palm kernel oil (PKO) [iodine value (IV) 18] on a pilot scale results in the following three end products: PKS IV 5 (yield: 29%, for direct use as CBS), PK olein IV 27 (yield: 58%), and PKS IV 7 (yield: 13% for use as CBS after full hydrogenation). The unhardened PKS IV 5 has outstanding melting and crystallization properties, comparable to traditional hydrogenated stearin fractions. Therefore, rather than the higher stearin yield, the reduced hydrogenation capacity is most probably the most important benefit of the two-stage static fractionation process.  相似文献   
47.
Bacterial toxins are food safety hazards causing about 10% of all reported foodborne outbreaks in Europe. Pertinent to Gram‐positive pathogens, the most relevant toxins are emetic toxin and diarrheal enterotoxins of Bacillus cereus, neurotoxins of Clostridium botulinum, enterotoxin of Clostridium perfringens, and a family of enterotoxins produced by Staphylococcus aureus and some other staphylococci. These toxins are the most important virulence factors of respective foodborne pathogens and a primary cause of the related foodborne diseases. They are proteins or peptides that differ from each other in their size, structure, toxicity, toxicological end points, solubility, and stability, types of food matrix to which they are mostly related to. These differences influence the characteristics of required detection methods. Therefore, detection of these toxins in food samples, or detection of toxin production capacity in the bacterial isolate, remains one of the cornerstones of microbial food analysis and an essential tool in understanding the relevant properties of these toxins. Advanced research has led into new insights of the incidence of toxins, mechanisms of their production, their physicochemical properties, and their toxicological mode of action and dose‐response profile. This review focuses on biological, immunological, mass spectrometry, and molecular assays as the most commonly used detection and quantification methods for toxins of B. cereus, C. botulinum, C. perfringens, and S. aureus. Gathered and analyzed information provides a comprehensive blueprint of the existing knowledge on the principles of these assays, their application in food safety, limits of detection and quantification, matrices in which they are applicable, and type of information they provide to the user.  相似文献   
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