• Journal of the Korean Ceramic Society
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• v.55 no.3
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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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• v.6 no.4
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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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• v.33 no.4
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• pp.301-306
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• 1990

The Physical and chemical properties or dry acorn starch(DS), detannined acorn starch (DTS) and defatted and detannined acorn starch(Drn) were investigated. Ail acorn starch sample, observed by a scanning electron microscope, showed a hemispherical shape ud its size was about $5{\sim}10{\mu}m$ in diameter. It had a little change on the pasting temperature of DS, DTS and DFTS but peak viscosity of DTS was somewhat higher than that of n. Flow behavior of gelatinized starch pastes showed a pseudoplastic behavior and flow behavior index was lower than unit. The consistency coefficient showed concentraion and temperature dependency. The activation energies of DS, DTS and DFTS were $2.09{\sim}3.58Kcal/g\;{\cdot}\;mol and time dependent characteristic of acorn starch samples showed thixotrpic behavior.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2003.10a
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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.

• Culinary science and hospitality research
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• v.20 no.1
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• pp.143-158
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• 2014

This study was conducted the physicochemical and sensory characteristics of Bulgogi sauce added with concentrated Curcuma longa L.. Increasing the amount of concentrated Curcuma longa L. in the Bulgogi sauce tended to increase the pH values, lightness(L), redness(a) and yellowness(b) values. It also tended to increase DPPH radical activity, but total polyphenol contents of Bulgogi sauce added with concentrated Curcuma longa L. were not significantly different among all the samples. In sensory evaluation, Bulgogi sauce added with 10% concentrated Curcuma longa L. had an excellent score in sensory taste, but Bulgogi sauce added with 20% concentrated Curcuma longa L. had an excellent score in overall preference. Seasoned roasted beef addition with 20% concentrated Curcuma longa L. had an excellent score in sensory preference. Therefore, this results suggest that 20% concentrated Curcuma longa L. should be applied to Bulgogi sauce for high sensory preference.

• The Korean Journal of Food And Nutrition
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• v.28 no.5
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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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• v.41 no.4
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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.

• Korean Journal of Food Science and Technology
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• v.18 no.6
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• pp.443-449
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• 1986

In order to investigate the general characteristics of ATPase and ATPase thermostability between porcine white muscle and red muscle, myofibrillar proteins were prepared and compared their physicochemical characteristics. SDS-polyacrylamide gel electrophoretic analyses showed that a protein band of 30,000 daltons was detected noticeably in myofibril from red muscle, but negligibly in myofibril from white muscle. The noticeable differences were found between porcine white muscle and red muscle for the activities of EDTA-ATPase, Ca-ATPase and Mg-ATPase. Myofibrillar proteins from white muscle showed higher thermostability than those from red muscle. Thermodynamic parameters, enthalpy $({\Delta}H^#)$, entropy $({\Delta}S^#)$, etc., showed characteristic variations between porcine white muscle and red muscle.

• Ocean and Polar Research
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• v.30 no.3
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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.

• The Journal of Korean Obstetrics and Gynecology
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• v.33 no.2
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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.