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91.
So-Yeon Kim Na-Kyoung Lee Eun Jin Han Hyun-Dong Paik 《Food science and biotechnology》2012,21(5):1433-1438
An antimicrobial peptide produced by Bacillus subtilis KU25, KU43, and KU44 was isolated from traditional Korean fermented foods and characterized. It was named as subtilin KU25, KU43, and KU44. Subtilin KU25, KU43, and KU44 were sensitive against α-chymotrypsin, protease XIII, and various proteinase enzymes, respectively. B. subtilis KU43 was selected as the producer with the broadest antimicrobial spectrum. Subtilin KU43 was stable at a pH range of 3 to 9 for 4 h, and withstood exposure to temperatures of 50–90°C for 30 min. The mode of inhibition against Listeria monocytogenes ATCC 15313 involved a bactericidal effect by a reduction in the cell numbers and breakage of the indicator cell membranes. The molecular mass of subtilin KU43 was measured at approximately 3.5 kDa. These results demonstrate the development of novel strains from traditional Korean fermented foods, and illustrate the possibility that some of these strains might generate a natural preservative compound. 相似文献
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93.
Myung Eun Suk Narayana R. Aluru 《Nanoscale and Microscale Thermophysical Engineering》2017,21(4):247-262
Carbon nanotube–based membranes have gained significant attention due to their transport efficiency and wide range of applications, including molecular sieving and sensing. Recently, in order to attain high transport rates, many studies have focused on reducing membrane thickness. A reduction in membrane thickness results in the dominance of entrance/exit effects over surface effects, particularly for carbon nanotubes (CNTs), due to their hydrophobicity. However, experimentally obtained nanoscale flow rate data span a wide range, and entrance/exit effects are often neglected when analyzing these data. In this study, we modeled the water flow rate through various lengths and radii of CNTs using molecular dynamics simulations while also taking entrance/exit effects into consideration. Based on viscosity and slip length calculations, a water flow model is proposed that covers various lengths and radii of CNTs. Moreover, the enhancement factor of CNT membranes is reassessed using entrance/exit effects. The results of this study can be used for the optimal design of ultraefficient CNT membranes for potential applications such as water filtration. 相似文献
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Hoon Chae Park Hang Seok Choi Ji Eun Lee 《Korean Journal of Chemical Engineering》2016,33(4):1159-1169
Rapid quenching of volatiles in fast pyrolysis is important for achieving high yield and quality of the bio-oil product, but few studies have examined the condensation of volatiles and their related heat exchangers. Accordingly, we have studied the condensation characteristics of volatiles by varying heat transfer conditions in a direct contact heat exchanger. As the mass flow rate ratio of quenching oil to pyrolysis gas increased, the heat transfer rate and yield of bio-oil increased. The heat transfer rate and yield of bio-oil reached a maximum value at an intermediate air-to-quenching oil mass flow rate ratio. Additionally, the heat transfer rate and yield of bio-oil decreased as the temperature of the quenching oil increased. Experiments were also conducted to derive an empirical relationship for the volumetric heat transfer coefficient for direct contact heat exchangers. 相似文献
96.
Abstract A simplified explicit formula for the displacement bounds of the beam‐column subjected to time‐dependent boundary constraints is proposed. The formula is derived by means of removing time dependence from the boundary conditions. The proposed bounds provide a quick estimation of the displacements for problems with complex loading conditions. 相似文献
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Su Won Park Soo Jin Lee You Sin Sim Jin Young Choi Eun Young Park Bong Soo Noh 《Food science and biotechnology》2017,26(2):311-317
The purpose of this study was to analyze ethanol content in soy sauce using mass spectrometry (MS) with electronic nose (e-nose) to determine if MS e-nose can replace gas chromatographic analysis for halal certification. Gas chromatography–flame ionization detector (GC-FID), the standard method of ethanol content, was used to analyze 24 different kinds of soy sauce. Ethanol was detected from 13 soy sauce samples in the concentration range of 0.0004–1.7wt%. The MS e-nose data were analyzed by discriminant function analysis (DFA). Based on an addition method, the results were more than 96.6% accurate when the ethanol concentrations were greater than 0.5%. A high correlation between the first score of the DFA plot and the ethanol concentration was observed. Thus, mass spectrometry based on e-nose is an efficient method for determining ethanol as a primary screening tool for halal certification. 相似文献
100.
Go Bong Choi Jong Woo Kim Jung Chul Suh Kwang Ho Jang Jong Min Lee 《Korean Journal of Chemical Engineering》2017,34(10):2584-2590
Pipe breaks in municipal water distribution networks may cause serious damage economically and socially. Existing methods for replacement scheduling of pipes do not provide practical indicators for replacing an individual deteriorated pipe. This work formulates the selection problem as the decision of preference ordering or ranking and proposes a bipartite ranking-based approach. The suggested approach also considers loss from broken pipes in terms of the costs associated with broken water main and its repair. We use rank aggregation method to integrate multiple ranks into replacement order of water mains. The suggested framework prioritizes current pipe sections for replacement based on the aggregated ranks. Multiple ranks given by the reliability of water pipe sections are aggregated and a cost effective policy for pipe replacement is derived. 相似文献