• 한국세라믹학회지
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• 제55권3호
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• pp.244-260
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• 2018

Issues in the electrical characterization of semiconducting photoanodes in a photoelectrochemical (PEC) cell, such as the cell geometry dependence, scan rate dependence in DC measurements, and the frequency dependence in AC measurements, are addressed, using the example of a $TiO_2$ photoanode. Contrary to conventional constant phase element (CPE) modeling, the capacitive behavior associated with Mott-Schottky (MS) response was successfully modeled by a Havriliak-Negami (HN) capacitance function-which allowed the determination of frequency-independent Schottky capacitance parameters to be explained by a trapping mechanism. Additional polarization can be successfully described by the parallel connection of a Bisquert transmission line (TL) model for the diffusion-recombination process in the nanostructured $TiO_2$ electrode. Instead of shunt CPEs generally employed for the non-ideal TL feature, TL models with ideal shunt capacitors can describe the experimental data in the presence of an infinite-length Warburg element as internal interfacial impedance - a characteristic suggested to be a generic feature of many electrochemical cells. Fully parametrized impedance spectra finally allow in-depth physicochemical interpretations.

• Interdisciplinary Bio Central
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• 제6권4호
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• pp.3.1-3.10
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• 2014

Amino acid substitution matrices are essential tools for protein sequence analysis, homology sequence search in protein databases and multiple sequence alignment. The PAM matrix was the first widely used amino acid substitution matrix. The BLOSUM series then succeeded the PAM matrix. Most substitution matrixes were developed by using the statistical frequency of substitution between each amino acid at blocks representing groups of protein families or related proteins. However, substitution of amino acids is based on the similarity of physiochemical properties of each amino acid. In this study, a new approach was used to obtain major physiochemical properties in multiple sequence alignment. Frequency of amino acid substitution in multiple sequence alignment database and selected attributes of amino acids in physiochemical properties database were merged. This merged data showed the major physiochemical properties through principle components analysis. Using factor analysis, these four principle components were interpreted as flexibility of electronic movement, polarity, negative charge and structural flexibility. Applying these four components, BAPS was constructed and validated for accuracy. When comparing receiver operated characteristic ($ROC_{50}$) values, BAPS scored slightly lower than BLOSUM and PAM. However, when evaluating for accuracy by comparing results from multiple sequence alignment with the structural alignment results of two test data sets with known three-dimensional structure in the homologous structure alignment database, the result of the test for BAPS was comparatively equivalent or better than results for prior matrices including PAM, Gonnet, Identity and Genetic code matrix.

• Applied Biological Chemistry
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• 제33권4호
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• pp.301-306
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• 1990

탄닌함량이 도토리전분의 물리화학적 성질에 미치는 영향을 탄닌함량을 달리한 도토리전분에서 비교 검토하였다. 탈탄닌 처리에 따른 전분 표면의 손상은 관찰되지 않았으며 탄닌함량은 도토리전분의 호화개시온도에는 영향을 미치지 않았으나 최고점도값에는 영향을 미치는 것으로 관찰되었다. 모든 시료전분의 유동거동지수값은 1보다 작았고(0$2.19{\sim}2.69Kcal/g\;{\cdot}\;mol$, 탈탄닌전분이 $2.31{\sim}3.33Kcal/g\;{\cdot}\;mol$, 탈지 및 탈탄닌전분이 $2.09{\sim}3.58Kcal/g\;{\cdot}\;mol$이었다. 전분호화액의 시간 의존성에서는 전분시료 모두 전단속도의 연속적인 증가와 감소에 따라 전단응력이 변화하는 thixotropic 거동을 보여주었으며 두개의 유동곡선은 서로 일치하고 않고 hysteresis loop을 형성하였다.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2003년도 추계학술대회 논문집
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• pp.93-96
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• 2003

Laser beam welding process is a relatively new process in comparison with arc welding process, but it is expected to apply widely because of the many advantages, and research and development of that process is being progressed actively for the practical use. the application of this welding process has been restricted due to the high initial investment and the need of precise processing against the material, but cost reduction and thick plate welding in high speed have become practial by recent technological development, and this welding process to not only small parts in automobile, machinery and physicochemical field, but also a large structure and pipe line are being applied. In order to utilize this welding process appropriately to a steel structure, the properties of welding residual stresses and fracture toughness in welded joints are to be investigated for relibilty. On this study, after performing the finite element analysis, thermal and residual stress properties have been examined to the general structural steel (HT50) by laser beam welding. Besides, the property of fracture toughness has been investigated by the Charpy impact test and 3-points bending CTOD test carried out in the range of temperature between $-60^{\circ}C$ and $20^{\circ}C$. From the research results it is revealed that the maximum residual stress appears in the center of plate thickness and the fracture toughness is influenced by strength mis-match.

• 한국조리학회지
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• 제20권1호
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• pp.143-158
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• 2014

본 연구는 울금 농축액을 첨가한 불고기 소스의 이화학적 특성 및 관능특성에 대하여 연구하였다. 불고기 소스의 울금 농축액의 첨가량이 증가할수록 pH가 높아지는 경향을 나타내었으며 불고기 소스의 울금 농축액의 첨가량이 증가할수록 색도(명도; L, 적색도; a, 황색도; b)도 높아지는 경향을 나타내었다. 울금 농축액 첨가 불고기 소스의 DPPH 라디컬 소거능은 울금 농축액의 첨가비율이 증가할수록 높아지는 경향을 나타내었으나, 총 폴리페놀 함량은 각 시료간 유의적인 차이를 나타내지 않았다. 관능평가에서는 울금 농축액 10% 첨가 소스가 맛 기호도 측면에서 가장 우수했던 반면, 전반적인 기호도 측면에서는 울금 농축액 20% 첨가 소스가 가장 우수하였다. 또한, 울금 농축액 20% 첨가 쇠고기 구이가 관능 기호도 측면에서 가장 우수하였다. 이상으로써, 불고기 소스의 관능적 기호성을 위해서는 울금 농축액 20%를 첨가하는 것이 가장 적합할 것으로 판단된다.

• 한국식품영양학회지
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• 제28권5호
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• pp.821-828
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• 2015

ASW0 is a polysaccharide derived from the perennial herb Aster scaber Thunberg. We isolated ASW0, a fraction of crude polysaccharide, by means of ethanol precipitation and dialysis after hot water extraction to investigate its physicochemical properties and immunostimulatory effects. ASW0 contains neutral sugar (45.7%), acidic sugar (51.6%), protein (2.3%), and 2-keto-3-deoxy-D-manno-octonate (KDO) (0.4%). The neutral sugar in ASW0 (in mole percentage) was mainly composed of arabinose (34.5 mol%), glucose (31.1 mol%), galactose (14.9 mol%), and rhamnose (8.1 mol%), which are characteristic of pectic polysaccharides. ASW0 also contained small amounts of xylose, mannose, and fucose. The anti-complementary activity of ASW-0 was similar to that of polysaccharide K (used as positive control). ASW0 exhibited no cytotoxicity in RAW 264.7 macrophages and dramatically increased nitric oxide (NO) production in a dose dependent manner ($0.3{\sim}30{\mu}g/mL$). Also, macrophages stimulated with ASW0 showed enhanced production of immunostimulatory cytokines such as interleukin-6 (IL-6) and tumor necrosis factor alpha ($TNF-{\alpha}$) in a dose dependent manner. These results suggest that the ASW0 have a potent immunostimulatory effect and can be used as a natural immune health ingredient.

• Journal of Pharmaceutical Investigation
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• 제41권4호
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• pp.227-232
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• 2011

Alnus japonica has been known to exert antioxidative, anti-inflammatory, anti-cancer and immune response inhibitory effects. The aim of this study was to figure out the characteristics of extracts obtained with different extraction solvent such as water, 100% ethanol, 70% ethanol or 70% methanol because characteristic components such as oregonin and hirsutanone extracted from Alnus japonica might be essential for the biological activity. For this purpose, oregonin and hirsutanon of four extracts, index ingredient of Alnus japonica, were analyzed with HPLC and physicochemical studies such as SEM, particle size and zeta potential were conducted. In cell cytotoxicity study, extract of water showed the highest cytotoxicity among four extracts. In case of oregonin, 70% MeOH and water extracts showed high contents and in case of hirsutanone, all extracts showed similar contents except 70% EtOH extracts. The extract of 70% MeOH from Alnus japonica for both oregonin and hirsutanone appeared to have the highest content. Both oregonin and hirsutanone extracted from Alnus japonica using 70% methanol showed stability in pH 1.2.

• 한국식품과학회지
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• 제18권6호
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• pp.443-449
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• 1986

근원섬유구성단백질의 SDS-polyacrylamide gel 전기 영동상으로 부터 돼지근육의 red muscle과 while muscle의 근원섬유단백질사이에는 30K성분함량의 특징적 차이가 나타났으며, 생물활성에서도 red muscle쪽이 white muscle쪽보다 높은 ATPase 활성을 나타내었다. 근원섬유단핵질의 열안정성은 D값에서 확실한 차이를 보여 white muscle쪽이 red muscle쪽보다 높은 열안정성을 나타냈고, 열역학량에서도 근섬유 type간의 차이를 보였다. 한편 근원섬유단백질의 열안정성은 생체조직에 가까운 형태일수륵 안정하다는 사실도 확인되었다.

• Ocean and Polar Research
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• 제30권3호
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• pp.261-275
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• 2008

The profile of a fixed site at station M ($34.77^{\circ}N,\;129.13^{\circ}E$) in the Korea Strait was studied from March 2006 to February 2007. The aim was to understand the relationship between the annual thermal stratification pattern and seasonal variation in phytoplankton community structure. Physicochemical factors including temperature, salinity and nutrient concentrations, which strongly influence the proliferation and diversity of phytoplankton, were measured. The study period was divided into three due to the characteristic of thermohaline structures; mixed I (March-May 2006), stratified (June-November 2006) and mixed II(December 2006-Feburuary 2007). Diatoms dominated during the mixed I (89%) and II (48%) periods, while nanoplankton group occupied over 83% of total population during the stratified period. The dominant species during the mixed I and II was Chaetoceros socialis (47% and 29%, respectively), while during the stratified period Gyrodinium sp.(4%) was the most dominant. Averaged total chl a concentrations during the mixed I and II periods were 0.61 mg $m^{-3}$ and 0.72 mg $m^{-3}$, respectively, which were at least two-fold higher than that during the stratified period (0.30 mg $m^{-3}$). The vertical mixing and convection process of the water column induced nutrient supply from the bottom layer to the euphotic zone. It also led to the dominance of diatoms during the mixed periods, whereas small phytoplankton prevailed over large phytoplankton as stratification blocked the upward movement of nutrients to subsurface during the stratified period. During the mixed I and II periods, microplanktonic chl a dominated concentrations (50% and 48%, respectively), while picoplanktonic chl a occupied over 37% of total chl a during the stratified period.

• 대한한방부인과학회지
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• 제33권2호
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• pp.1-12
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• 2020

Objectives: This study was conducted to find out the optimal extraction time for Artemisia argyi. Methods: The compositional pattern was compared with HPLC (High Performance Liquid Chromatography) and GC (Gas-Chromatography) by decocting Artemisia argyi 10, 60, 120 minutes respectively. Results: With longer extraction time, the contents of reference compounds were extracted 1.1 times more when 3,4-dicaffeoylquinic acid was extracted for 60 minutes than when extracted for 10 minutes in HPLC test, but the contents were reduced when extracted for 120 minutes compared to 60 minutes extraction time. 3,4-di-O-caffeoylquinic acid, 3,5-di-O-caffeoylquinic acid, 4,5-di-O-caffeoylquinic acid, jaceosidin, and eupatilin showed the largest yield rate when extracted for 10 minutes, and it decreased as time passed. The contents of chlorogenic acid, 3,5-dicaffeoylquinic acid, 4,5-dicaffeoylquinic acid, jaceosidin, scoparone, and eupatilin were detected only in 10 minutes extraction but not in 60 or 120 minutes extraction according to GC test. Conclusions: The results show that extraction time could affect the physicochemical characteristic or composition of Artemisia argy extracted. Thus, short extraction time could be useful for decoction of Artemisia argyi.