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981.
The authors present a comprehensive evaluation of phase behaviors of alkaline/surfactant/polymer (ASP) systems. The experimental results proved that the phase behavior of mixed-surfactant solutions (single- and double-tail anionic surfactants) would be better than the one of single surfactant. These mixtures were also more compatible with polymer, and adjusted optimum salinity to the reservoir brine. They next examined the role of alkalis in ASP process. Three types of alkalis were tested to select the optimum one for high-temperature reservoir. This study showed that sodium metaborate is the best choice. 相似文献
982.
A smart decontamination device is developed for small-size radioactive scrap metal (SSRSM) arisen from nuclear facilities.The abrasion pin in rotating magnetic field and ultrasonic wave cleaner are used for solving the problems of the second decontamination and high treatment cost.At first,the decontamination efficiency of each device is improved by upgrading the design.Optimal operating conditions are determined for each device.Next,both techniques are applied sequentially.Experimental results show that the efficiency of combined decontamination device is higher than that of each device.With the use of the developed device,the various SSRSMs are decontaminated for 15 min treatment in magnetic abrasion device and 15 min treatment in ultrasonic cleaning device.Decontamination index ranges from 18 to 56.Absolute values of all decontaminated samples are below the background value. 相似文献
983.
New supramolecular ligands possessing linear 13- and 15-membered pyridine diamidetriamine chelators between the primary sides of two beta-cyclodextrin cavities were synthesized, and characterized by MALDI-MS, NMR, IR and UV-Visible spectroscopy. Fluorescence and pH-metric titration were carried out in order to ascertain their behavior as bifunctional hosts for fluorescent guests and Cu(II) ion. The pKa value for the Cu(II) promoted deprotonation of amide ligands was determined to be 6.2 from pH-absorbance profile. Above pH 8.0, two deprotonated amides and three amino groups chelated Cu(II) ion, and yielded penta-coordinated Cu(II) complexes. The Cu(II) complexes catalyzed the hydrolysis of p-nitrophenyl acetate, adamantate and amino acids. Especially, the complex containing 13-membered chelator is an artificial metalloesterase with catalytic rate constant kcat = 3.8 x 10(-3) min-1 and Michaelis constant K(m) = 3.5 x 10(-4) M for the hydrolysis of p-nitrophenyl adamantate via metal-hydroxide mechanism. 相似文献
984.
Effect of Lentinus edodes β-Glucan-Enriched Materials on the Textural, Rheological, and Oil-Resisting Properties of Instant Fried Noodles 总被引:1,自引:0,他引:1
Soojung Heo Seung Mi Lee In Young Bae Hyuk-Gu Park Hyeon Gyu Lee Suyong Lee 《Food and Bioprocess Technology》2013,6(2):553-560
With the recent well-being trend, a great deal of effort has been made to develop instant fried noodles with beneficial health effects. Thus, β-glucan-enriched materials (BGEMs) were obtained from Lentinus edodes mushroom and their effects on the quality attributes of instant fried noodles were characterized in terms of rheological, textural, and oil-resisting properties. When BGEMs were mixed with wheat flour, different thermomechanical profiles were observed by a Mixolab, enhancing dough stability and water absorption. The use of BGEMs raised the viscoelastic properties of noodle dough with a great increase in the elastic property. In addition, the dough samples prepared with more BGEMs exhibited greater elongational viscosity. In the case of fried noodle strands, the incorporation of BGEMs led to a significant increase in the breaking stress and produced a surface microstructure with smaller voids. Moreover, the oil uptake of fried noodles containing BGEMs was significantly reduced by 22%. Therefore, it showed that BGEMs had positive impacts on the quality attributes of instant fried noodles and could also be used as an oil barrier to produce fried noodles with a reduced content of oil and calories. 相似文献
985.
986.
987.
Eunseuk Park Hoanganh Le Sungmin Chin Joosik Kim Gwi-Nam Bae Jongsoo Jurng 《Journal of Porous Materials》2012,19(5):877-881
TiO2 particles were prepared by chemical vapor condensation and used to synthesize MnOx/TiO2 mesoporous materials by impregnation. The Mn-doped TiO2 particles were smaller (8.5?nm vs. 10.5?nm) and had greater surface areas (203.7?m2?g?1 vs. 134.4?m2?g?1) than undoped particles. They were also smaller and had a greater surface area than similarly doped commercial P25, indicating highly dispersed Mn species on the surfaces of the crystalline TiO2. The resulting materials?? photocatalytic activities towards methylene blue decomposition were compared: the synthesized TiO2 particles with MnO2 showed higher photocatalytic activity than the similarly doped commercial P25. 相似文献
988.
989.
Bae SH Choi JW Ra KS Yu KW Shin KS Park SS Suh HJ 《Journal of the science of food and agriculture》2012,92(8):1765-1770
BACKGROUND: Makgeolli brewed from rice contains about 150 g kg?1 alcohol and has a fragrance as well as an acidic and sweet taste. During the brewing process, by‐products such as rice bran and brewery cake are produced. At the end of fermentation the matured mash is transferred to a filter cloth and the Makgeolli is squeezed out from the cake, leaving the lees of the mash. These by‐products have continued to increase every year, resulting in an ecological problem. It is therefore important to develop new uses for them. The objective of this study was to use the by‐products from the brewing of Makgeolli as a valuable functional food or nutraceutical. RESULTS: The anti‐complementary activities of crude polysaccharides isolated from Cytolase hydrolysates of Makgeolli lees at concentrations of 1000 and 500 µg mL?1 were 84.15 and 78.70% respectively. The activity of polysaccharide krestin (PSK) was 60.00% at 1000 µg mL?1. The active polysaccharide obtained with Cytolase comprised mainly glucose and mannose (molar ratio 1.00:0.62). CONCLUSION: Glucose‐ and mannose‐rich crude polysaccharides were isolated from the Cytolase hydrolysate of Makgeolli lees. The polysaccharides retain anti‐complementary activity to enhance the immune system as a functional food or nutraceutical. Copyright © 2011 Society of Chemical Industry 相似文献
990.
Abstract: Pathogens that contaminate the surfaces of food utensils may contribute to the occurrence of foodborne disease outbreaks. We investigated the efficacy of UV treatment combined with dry heat (50 °C) for inhibiting 5 foodborne pathogens (Escherichia coli O157:H7, Salmonella Typhimurium, Pseudomonas aeruginosa, Listeria monocytogenes, and Staphylococcus aureus) on stainless steel and polypropylene surfaces in this study. We inoculated substrates with each of the 5 foodborne pathogens cultured on agar surface and then UV treatment alone or a combination of both UV and dry heat (50 °C) was applied for 30 min, 1 h, 2 h, and 3 h. The initial populations of the 5 pathogens before treatment were 8.02 to 9.18 and 8.73 to 9.16 log10 CFU/coupon on the surfaces of stainless steel and polypropylene coupons, respectively. UV treatments for 3 h significantly inhibited S. Typhimurium, L. monocytogenes, and S. aureus on the stainless steel by 3.06, 2.18, and 2.70 log10 CFU/coupon, and S. aureus on the polypropylene by 3.11 log10 CFU/coupon, respectively. The inhibitory effects of the combined UV and dry heat treatment (50 °C) increased as treatment time increased, yielding significant reductions in all samples treated for 3 h, with the exception of S. aureus on polypropylene. The reduction level of E. coli O157:H7 treated for 3 h on the surface of stainless steel and polypropylene treated was approximately 6.00 log10 CFU/coupon. These results indicate that combined UV and dry heat (50 °C) treatments may be effective for controlling microbial contamination on utensils and cooking equipment surfaces as well as in other related environments. 相似文献