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41.
New anionic surfactants 2-alkyloyl-1,4,3,6-dianhydrosorbitol-5-sulfates were synthesized by sulfation of 2-alkyloyl-1,4,3,6-dianhydrosorbitol. Studies on the surface active properties such as surface tension, dispersibility and emulsifiability of these surfactants were carried out. The results showed these surfactants are better dispersants and emulsifiers than Span 80 and Span 85.  相似文献   
42.
The XT-ADS, an accelerator-driven system for an experimental demonstration, has been investigated in the framework of IP EUROTRANS FP6 project. In this study, the sensitivity and uncertainty analyses were performed to comprehend the reliability of the XT-ADS neutronic design.  相似文献   
43.
A series of AZO films were grown on glass substrates by a method of pulsed laser deposition using a split target divided into AZO (Al2O3: 1 wt.%) and AZO (Al2O3: 2 wt.%). The film deposition took place at a substrate temperature of 230 °C within a magnetic field applied perpendicularly to the plume. To suppress the droplet generation caused by the intense laser energy, the laser energy density was reduced to 0.75 J/cm2 (15 mJ). For an approximately 280-nm thick-AZO film grown at a target-to-substrate distance of 25 mm, we obtained the lowest resistivity of 8.54×10−5 Ω·cm and an average transmittance of more than 88% in the visible range. In the cross-sectional TEM observation and XRD spectra, the regularity in the crystal growth was generated immediately from the interface between the substrate and the film.  相似文献   
44.
A new prediction method for the thermal ratchetting of a cylinder subjected to an axially moving temperature distribution is proposed in this paper. This ratchetting is quite different from the conventional Bree-type ratchetting, and an advanced evaluation method has been required in the structural design of FBR components. The proposed method considers the work hardening of actual materials for FBR components. Firstly the basic scheme of the prediction method is shown, and secondly the application procedure to the actual design is shown. Predicted results by using this method coincide well with experimental results, when compared with the case by using the previous method.  相似文献   
45.
The adsorption abilities of chitin and its congeners with two series of degrees of deacetylation prepared by two different deacetylation procedures were compared. Among the polysaccharides obtained by the heterogeneous method, those with higher amino group content had higher adsorption ability. Plots of collection percentages versus amino group content, however, did not give straight lines. The plot for the chelation on the congeners that were prepared by homogeneous hydrolysis had a maximum at about 50% amino group content, and the value was higher than that for the sample with the highest amino group content, which was prepared by heterogeneous hydrolysis. These results suggest that the polysaccharides with about 50% amino group content obtained by the homogeneous procedure are potentially useful for the removal of metals.  相似文献   
46.
Effect of baffle on a tray under oscillating conditions has been examined experimentally. To reduce the degree of liquid mixing and liquid channeling under oscillating conditions, it is necessary to install the baffles on tray.

Experiments were conducted with the air-water system, ft was found that the pressure drop change can be expressed as a sinusoidal function and the period coincides with tray oscillation. The degree of liquid mixing decreases when the baffles are installed on tray and it also decreases with the increase of liquid flow rate. The pressure drop increases with the installation of baffle on tray.

The suitable baffle number on tray is from 4 to 8 and in this region, the degree of liquid mixing reaches minimum and the liquid holdup takes a maximum value. @KEYWORDS: Tray, Oscillating, Liquid mixing, Baffle, Pressure drop, Liquid holdup.  相似文献   
47.
The emissivity of chlorinated polyethylene containing varying amounts of combined chlorine has been investigated. It was found that the emissivity of these compounds increases significantly with increase in chlorination.  相似文献   
48.
49.
Anthocyanins are one type of flavonoid phytopigment. Although the role of anthocyanins as a functional food factor remains relatively less established than that of other flavonoids, progress in this area has been made at the molecular level in recent years. This review discusses the potential health benefits of plant-derived anthocyanin-rich foods, with a focus on the role of anthocyanins in obesity control, diabetes control, cardiovascular disease prevention, and improvement of visual and brain functions, areas that have attracted much attention. Such health benefits are not necessarily derived from the antioxidant effect of anthocyanins, but in fact are produced by currently unestablished chemical properties beyond the antioxidant capacity of the molecules. However, a better understanding of the physiological functionality of anthocyanins remains to be elucidated. It is desirable, therefore, to clarify the molecular type and composition of the anthocyanins that confer specific health benefits and to conduct further investigation into the underlying molecular mechanisms. The pharmacological actions of anthocyanins could not be fully established without knowledge on the effects of treatment of anthocyanins alone, the effects of non-anthocyanin components, and the possible interactions between anthocyanin and non-anthocyanin species.  相似文献   
50.
Rapidly dried onion (Allium cepa L. cv. Momiji No. 3) powder (OP) prepared from the outer layers (from second to fourth scale leaves from the surface) of onion bulbs was analysed for its quercetin and polyuronide contents, the effects of enzymatic treatment and the anti-atherogenic effect on rats fed a high-fat diet. Quercetin 4′-glucoside (50%), free quercetin (30%) and quercetin 3,4′-diglucoside (20%) were identified as quercetin derivatives, and boiling-water extraction was effective in extracting these compounds. OP contained 12.9% of polyuronides, the basic skeleton of pectin. Enzymatic degradation (cellulase and pectinase, 50 °C for 12 h, pH 6.0) of OP was effective in obtaining a slurry of smaller particle sizes. The free quercetin increased and the glucosides decreased with enzyme treatment. In Wistar rats fed an OP-added high-fat diet, the total cholesterol, HDL-cholesterol and triglyceride concentrations were not significantly different from the rats fed a high-fat diet without OP. However, the atherogenic index (AI) of Wistar rats fed an OP-added high-fat diet was lower (AI = 3.3) than rats fed the diet without OP (AI = 4.1). The incremental elastic modulus (IEM) of the aorta from rats fed the OP-added diet was also significantly lower than that of the rats fed the diet without OP. The AI and IEM values of the rats fed the OP-added diet were quite similar to the values of rats fed the diet without OP but were allowed spontaneous exercise. These results suggest that OP intake is effective for decreasing the risk of arteriosclerosis.  相似文献   
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