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排序方式: 共有667条查询结果,搜索用时 0 毫秒
661.
662.
Kuk-Hwan Seol Juhui Choe Hyun-Jin Kim Jin-Taek Hwang Mooha Lee 《International Journal of Food Properties》2018,21(1):205-212
In this study, crude peptide fractions from Hanwoo loins were released by injecting with proteolytic enzymes [no enzymes (control); protease type XIII (E1); thermolysin (E2); and combination of E1 and E2 (E3)] and their bioactivities were determined. The peptides derived from E2-injected Hanwoo loin exhibited the highest angiotensin I–converting enzyme (ACE) inhibitory activity and vitamin C equivalents antioxidant capacity among the treatments. The released peptide by treatment of E2 and E3 had similar (P > 0.05) inhibitory activity in HT29 cancer cell viability compared with luteolin as a positive control and non-cytotoxic effect on normal cell (3T3-L1). Therefore, the released peptide fraction from thermolysin (E2)-injected Hanwoo beef might contain potent bioactive peptides with ACE inhibitory and antioxidative activity and inhibition effect on certain cancer cell viability. 相似文献
663.
First flush analysis of urban storm runoff 总被引:49,自引:0,他引:49
Stormwater runoff was monitored on 13 separate urban watersheds, which were chosen to represent distinct types of residential and industrial development, along with various watershed characteristics. A total of 38 storm events were monitored to investigate the first flush phenomenon. The first flush phenomenon may be defined as the initial period of stormwater runoff during which the concentration of pollutants is substantially higher than during later stages. The magnitude of the first flush phenomenon, and if it actually occurs, was calculated using a method of data analysis which results in determining the 'event mean concentration' (EMC). The magnitude of the first flush phenomenon was found to be greater for some pollutants (e.g. suspended solids from residential areas) and less for others (e.g. chemical oxygen demand from industrial areas). No correlation was observed between the first flush phenomenon and the antecedent dry weather period, however, the first flush phenomenon was greater for smaller watershed areas. 相似文献
664.
Flow characteristics, axial dispersion coefficients in the continuous phase, and holdup of the dispersed phase were studied
in a 4.66 cm inside diameter and 100 cm height column agitated by blade impellers.
Flow characteristics were analyzed by residence time distribution using impulse input of a tracer. The best reasonable values
of Peclet number and holding time were able to obtain by using the response surface method.
The axial dispersion coefficients in the single phase flow, and in the two-phase countercurrent flow have been correlated
within a confidence level of ±10% when impeller diameter, impeller speed and compartment height, were used as variables. The
holdup of the dispersed phase was also correlated in terms of impeller diameter and the operating variables. 相似文献
665.
Preparation of Silica/γ-Alumina Membrane with Bimodal Porous Layer for Improved Permeation in Ions Separation 总被引:1,自引:0,他引:1
Abdul Latif Ahmad Choe Peng Leo Syamsul Rizal Abdul Shukor 《Journal of the American Ceramic Society》2008,91(6):2009-2014
Creating secondary pores in the intermediate layer of hierarchical ceramic membranes successfully increases the permeability of bi-layered membranes by reducing the density of the separating layer. With the optimum secondary pore volume, the permeability of the silica/γ-alumina membrane with low secondary volume is enhanced with a satisfactory retention of organic ions and inorganic ions. However, the silica layer is not well formed when excessive secondary pores were generated in the intermediate layer. This is likely because the bimodal porous structure of γ-alumina with high secondary pore volume is inadequate to prevent the penetration of silica sol into the α-alumina support during dip coating. Thus, the bi-layered membrane with high secondary pore volume shows insufficient retention of Reactive Orange 16 dye and NaCl at low pH. 相似文献
666.
Lead zirconate titanate [Pb(Zr0.52, Ti0.48)O3 (PZT)] films were grown by sol–gel process on nickel and hastelloy foils. PZT perovskite phase was obtained at 650 °C annealing condition and surface topography showed uniform and dense microstructure. The characterization on dielectric properties indicates that diffusion of foil elements into the PZT and the formation of low capacitance interfacial layer occur during process. In order to reduce the diffusion effect of foil element and/or interfacial layer, barrier layers such as Ru(RuO2) and LaNiO3 layers were utilized on foil substrates. The increase of grain size was observed in PZT films grown on barrier layers. Dielectric properties are greatly improved without degrading ultimate dielectric breakdown strength. 相似文献
667.
A systematic approach to new mobile service creation 总被引:1,自引:1,他引:0
Chulhyun Kim Suhwan Choe Changwoo Choi Yongtae Park 《Expert systems with applications》2008,35(3):762-771
In spit of the growing importance of new service creation (NSC), especially new mobile service creation, most of the previous studies on NSC have been conceptual and focused on the traditional services. In response, this study suggests a new systematic approach to new mobile service creation. At first, morphological analysis is applied to identify the structure of services. Specifically, the dimension parameters are defined by decomposing the service system into basic components and the shape parameters are defined by mapping keywords extracted from business method patents through text mining. Then, by applying conjoint analysis, the promising configurations of mobile services are derived. Finally, the Kano model is applied to evaluate the requirement type of alternatives. The proposed approach can generate and evaluate the service concepts systematically. The detailed procedure of the approach is illustrated based on the case of mobile entertainment services. The proposed approach is expected to help service designers in real service creation processes. 相似文献