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41.
Hanyeong Park Minhee Lee Kee-Tae Kim Eunju Park Hyun-Dong Paik 《Journal of dairy science》2018,101(10):8702-8710
The purpose of this study was to evaluate the antioxidant and antigenotoxic effect of dairy products milk (M) and yogurt (Y) after the addition of 2% red ginseng extract to milk (RM) and to yogurt (RY). Total phenolic content, total flavonoid content, 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity, oxygen radical absorbance capacity, and total radical trapping antioxidant potential were determined in the samples. Furthermore, antigenotoxic effect of samples was measured, using comet assay in human leukocytes. Total phenolic content and total flavonoid content of RM [38.3 ± 0.8 mg of gallic acid equivalents (GAE)/100 g, 23.6 ± 0.1 mg of quercetin equivalents (QE)/100 g] and RY (41.1 ± 0.9 mg of GAE/100 g, 18.7 ± 0.1 mg of QE/100 g), respectively, were higher than those of M (6.31 ± 0.2 mg of GAE/100 g, 10.4 ± 0.1 mg of QE/100 g) and Y (8.1 ± 0.9 mg of GAE/100 g, 8.4 ± 0.2 mg of QE/100 g), respectively. The 2,2-diphenyl-1-picrylhydrazyl radical scavenging activity and oxygen radical absorbance capacity values increased significantly after the addition of 2% red ginseng in both. Additionally, the total radical trapping antioxidant potential in RM (787.7 ± 7.0 μg/mL) was lower than in M (2074.0 ± 28.4 μg/mL). The H2O2-induced DNA damage in RY (0.1 ± 0.0 mg/mL) was less than the damage in Y (0.4 ± 0.0 mg/mL), but we found no significant difference between M and RM. This study indicates that supplementation with red ginseng can fortify the antioxidant and antigenotoxic effects of dairy products effectively. 相似文献
42.
Synthesis of BaCu(B2 O5 ) Ceramics and their Effect on the Sintering Temperature and Microwave Dielectric Properties of Ba(Zn1/3 Nb2/3 )O3 Ceramics 总被引:1,自引:0,他引:1
Min-Han Kim Jong-Bong Lim Jae-Chul Kim Sahn Nahm Jong-Hoo Paik Jong-Hee Kim Kyeong-Soon Park 《Journal of the American Ceramic Society》2006,89(10):3124-3128
BaCu(B2 O5 ) ceramics were synthesized and their microwave dielectric properties were investigated. BaCu(B2 O5 ) phase was formed at 700°C and melted above 850°C. The BaCu(B2 O5 ) ceramic sintered at 810°C had a dielectric constant (ɛr ) of 7.4, a quality factor ( Q × f ) of 50 000 GHz and a temperature coefficient of resonance frequency (τf ) of −32 ppm/°C. As the BaCu(B2 O5 ) ceramic had a low melting temperature and good microwave dielectric properties, it can be used as a low-temperature sintering aid for microwave dielectric materials for low temperature co-fired ceramic application. When BaCu(B2 O5 ) was added to the Ba(Zn1/3 Nb2/3 )O3 (BZN) ceramic, BZN ceramics were well sintered even at 850°C. BaCu(B2 O5 ) existed as a liquid phase during the sintering and assisted the densification of the BZN ceramic. Good microwave dielectric properties of Q × f =16 000 GHz, ɛr =35, and τf =22.1 ppm/°C were obtained for the BZN+6.0 mol% BaCu(B2 O5 ) ceramic sintered at 875°C for 2 h. 相似文献
43.
Modern digital communication systems rely heavily on baseband signal processing for in-phase and quadrature (I-Q) channels, and complex number processing in low-voltage CMOS has become a necessity for channel equalization, timing recovery, modulation, and demodulation. In this work, redundant binary (RB) arithmetic is applied to complex number multiplication for the first time so that an N-bit parallel complex number multiplier can be reduced to two RE multiplications (i.e., an addition of N RB partial products) corresponding to real and imaginary parts, respectively. This efficient RE encoding scheme proposed can generate RB partial products with no additional hardware and delay overheads. A prototype 8-bit complex number multiplier containing 11.5 K transistors is integrated on 1.05×1.33 mm2 using 0.8 μm CMOS. The chip consumes 90 mW with 2.5 V supply when clocked at 200 MHz 相似文献
44.
Seasoned beef called Jangzorim in Korea is produced by boiling in soy sauce, and is a popular food in Korea. The aim of this study is to evaluate the microbial safety and physical qualities of sous vide processed seasoned beef, and the effect of nisin during storage. Sous vide processed packages with or without nisin (100 IU or 500 IU) were stored at 4 °C or 25 °C for 60 days, and samples measured for quality at regular intervals throughout this storage period. In the case of 25 °C storage, the number of mesophilic microorganisms in seasoned beef packages without nisin increased markedly, but with nisin there was no observed increase. Psychrotrophic microorganisms, anaerobic microorganisms, and B. cereus cells showed similar trends, although C. perfringens was not detected in all samples. At 25 °C storage, changes in the cutting force of packages containing nisin showed no significant change, packages without nisin decreased markedly. The colour of packages without nisin showed a drastic decrease in lightness (‘L’) while no changes were observed in packages with nisin. 相似文献
45.
AbstractThis study examines how R&D intensity and open innovation affect the technological capabilities of firms in newly-developed countries, such as South Korea. East Asian latecomers are transitioning from a catch-up phase toward becoming leaders, and they are engaging in open innovation activities to drive this transition. This research quantitatively analyzes three kinds of open innovation activities—outside-in, inside-out, and coupled—to investigate their influence upon technological capabilities, while also considering the effect of R&D intensity. Data from 75 South Korean medium-sized firms were analyzed, and two major findings are reported. First, technological capabilities are enhanced by some open innovation activities and by R&D intensity. Second, R&D intensity negatively moderates the impact of open innovation activities on technological capabilities. Therefore, it may be concluded that firms with relatively low R&D intensity will gain the most benefit from increasing their open innovation activities. 相似文献
46.
Keun Young Min Hyun Jung Kim Kyoung Ah Lee Kee-Tae Kim Hyun-Dong Paik 《Journal of dairy science》2014
Citrus fruit (Citrus unshiu) peels were extracted with hot water and then acid-hydrolyzed using hydrochloric acid. Antimicrobial activities of acid-hydrolyzed Citrus unshiu peel extract were evaluated against pathogenic bacteria, including Bacillus cereus, Staphylococcus aureus, and Listeria monocytogenes. Antilisterial effect was also determined by adding extracts at 1, 2, and 4% to whole, low-fat, and skim milk. The cell numbers of B. cereus, Staph. aureus, and L. monocytogenes cultures treated with acid-hydrolyzed extract for 12 h at 35°C were reduced from about 8 log cfu/mL to <1 log cfu/mL. Bacillus cereus was more sensitive to acid-hydrolyzed Citrus unshiu peel extract than were the other bacteria. The addition of 4% acid-hydrolyzed Citrus unshiu extracts to all types of milk inhibited the growth of L. monocytogenes within 1 d of storage at 4°C. The results indicated that Citrus unshiu peel extracts, after acid hydrolysis, effectively inhibited the growth of pathogenic bacteria. These findings indicate that acid hydrolysis of Citrus unshiu peel facilitates its use as a natural antimicrobial agent for food products. 相似文献
47.
Hwack Joo Lee Hyun Ryu Hyun Min Park Jong Hoo Paik Sahn Nahm Jae-Dong Byun 《Journal of the American Ceramic Society》1998,81(6):1685-1688
Microstructural studies on the interfacial boundaries of 1:1 and 1:2 ordered domains in (Ba0.9 La0.1 )(Mg0.37 Nb0.63 )O3 were conducted using high-resolution transmission electron microscopy and X-ray diffractometry. Both 1:2 and 1:1 ordered domains coexisted in a fully ordered single grain. Each ordered domain occupied its own region, and the interfaces were atomically sharp and coherent. The wavelength of the superlattice modulation was ∼0.47 nm in the 1:1 ordered domain and ∼0.71 nm in the 1:2 ordered domain. The transition from the 1:2 ordered region to the 1:1 ordered region was clearly shown at the interface. These observations well support the structural models that have been previously presented. 相似文献
48.
Jeom Kee Paik 《钢结构》2008,(4)
众所周知,与其他因素相比焊接引起的初始挠曲会极大地影响被焊板的极限强度,这意味着在计算板的极限强度以前判别板的初始挠曲性状是极其重要的。本文旨在研究海洋工程中应用的铝板在焊接过程中产生的初始挠曲特性。研究中共有78个单跨和多跨加劲平板铝结构,其与80m长全铝制高速船的基础结构同尺寸,采用金属惰性气体焊接。然后计算出加劲肋之间的初始挠曲。通过对数据库进行统计分析,得到初始挠曲变化系数。研究结果有助于焊接铝板结构的可靠性分析、极限强度确定和制作工艺控制。 相似文献
49.
Jae?H.?KimEmail author Jung?M.?Lee Ho?C.?Shin Young?H.?Paik 《Metals and Materials International》2003,9(6):593-597
It is known that oxide inclusions in liquid metal carry mostly positive charges on their surfaces. In an electrostatic field,
therefore, such charged particles suspended in a liquid metal experience forces and accumulate in the region of the negatively
charged surface, resulting in the separation of oxide inclusions from the liquid metal. In this study, this principle was
experimentally demonstrated for the case of a capacitor cell by the imposition of a d.c. potential on electrodes. The capacitor
cell consisted of a dielectric container of Pyrex tube, a high voltage d.c. source, and two electrodes, which were symmetrically
attached onto the outer surface of the Pyrex. tube. Experiments were carried out for suspensions of liquid tin/metal oxides,
such as SnO2, WO3, and PbO under an applied potential of up to 12 kV. All experimental results were in good agreement with the theoretical
prediction and showed that the degree of separation was significantly increased with the applied potential. 相似文献
50.
C Wu H Kobayashi B Sun TM Yoo CH Paik OA Gansow JA Carrasquillo I Pastan MW Brechbiel 《Canadian Metallurgical Quarterly》1997,5(10):1925-1934
Distinct differences in in vivo stability of the two diastereomeric C-Functionalized CyDTPA chelating agents, (CHX-A DTPA and CHX-B DTPA, both racemates), as recently reported prompted further investigation as to why differences in configuration produced striking effects on the in vivo stability of their yttrium complexes. To this end, the four individual component stereoisomers of CHX-A and CHX-B were synthesized and ability to bind yttrium was investigated both in vitro and in vivo. 相似文献