• Journal of the Korean Society of Food Science and Nutrition
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• v.13 no.4
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• pp.397-402
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• 1984

As a basic research for inhibition of enzymatic browning of apple wine, polyphenol oxidase (EC 1.10.3.1) from apple (Jonathan) was extracted, partially purified, and some properties of the enzyme and changes o( active bands by heat treatment were investigated. Optimum conditions for the enzyme reaction were pH6.5 and temperature of $30^{\circ}C$, and o-diphenol was the main substrate for the enzyme. Approximately 35% and 15% of initia lpolyphenol oxidase activity remained after heating at $60^{\circ}C$ and $70^{\circ}C$ for 1 hour, respectively. About 0.5mM of the inhibitor such as sodium metabisulfite, cysteine and ascorbic acid was required for effective inhibition of the enzyme reaction. However, EDTA was found to be a very poor inhibitor. Ethanol did not affect the enzyme activity. The number of active bands of polyphenol oxidase from apple(Jonathan) was found to be four, but two bands and one band were observed after heating at $60^{\circ}C$ and $70^{\circ}C$ for 1 hour, respectively, which showed a significant difference in thermal stability among active bands.

• Journal of the Korean Society of Food Science and Nutrition
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• v.36 no.6
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• pp.689-695
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• 2007

Antioxidative activity and polyphenol contents of heated licorice in Korea extracted by ethyl.acetate (EtOAc) and ethyl.alcohol (EtOH) were evaluated at various heating temperatures (110, 120, 130, 140, and $150^{\circ}C$), times (1, 2, 3, 4, and 5 hr), and moisture contents (10, 20, 30, 40, and 50%). Maximum extraction yields of EtOAc extract was 10.9% at $130^{\circ}C$, 3 hr, and 50% moisture content and that of EtOH extract was 25.0% at $120^{\circ}C$, 2 hr, and 20% moisture content, whereas those of control were 0.8 and 15.8%, respectively. The highest total polyphenol content was 845.67 mg/100 g in EtOH extract at $120^{\circ}C$, 2 hr, and 20% moisture content (control: 277.00 mg/100 g). The antioxidative activity ($IC_{50}$) was the highest value of 0.53 mg/mL in EtOAc extract at $120^{\circ}C$, 2 hr, and 20% moisture content (control: 12.34 mg/mL). The highest ascorbic acid equivalent antioxidant activity value of 1,584 mg ascorbic acid (AA) eq was obtained from EtOAc extract at $120^{\circ}C$, 2hr, and 40% moisture content (control: 1,263 mg AA eq). Optimum heating conditions for the improvement of antioxidative activity of licorice in Korea was $120^{\circ}C$, 2 hr, and $20{\sim}40%$ moisture content.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.36 no.2
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• pp.80-87
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• 2003

Recovery conditions and characteristics of a high molecular soluble protein from surimi processing wastewater in marine manufacture using calcium powder of cuttle bone treated with acetic acid (ATC) were examined. Judging from results of total-N, pH, COD, turbidity and yields, optimal treatment concentration of ATC for recovery of high molecular soluble proteins from wastewater was $1.0\%.$ The protein recovered from seafood waste (PRW) was macromolecule weight. The COD value in the wastewater treated with ATC was very high. The PRW had a $78.4\%$ in moisture, $1.0\%$ in crude lipid and $5.7\%$ in crude ash. The proximate composition, except the crude ash, of the PRW was similar to that of commercial surimi. The PRW showed white index and similar in the content and in the composition of total amino acid to those of commercial surimi. From the results of sensory evaluation on white index and texture, the heat-induced surimi gel prepared with $5\%$ subsititution of the PRW for bulking agent of commercial surimi was not significantly different compared to that prepared with the original commercial surimi.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.15 no.3
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• pp.124-127
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• 2005

It is demonstrated that the annealing process for Ti in-diffusion to z-cut $LiNbO_3$ at temperature lower than the curie temperature in a platinum (Pt) box can cause a ferroelectric micro-domain inversion at the +z surface and Li out-diffusion, therefore which should be avoided or suppressed for waveguide type periodically poled lithium niobate (PPLN) devices. The depth of the inversion layer depends on the Ti-diffusion conditions such as temperature, atmosphere, the sealing method of $LiNbO_3$ in the Pt box and crystal orientation is experimentally examined. The result shows that the polarization-inverted domain boundary appears at the only +z surface and its thickness is about $1.6{\mu}m$. Also, for the etched $LiNbO_3$, surface the domain shape was observed by the optical microscope and atomic force microscopy (AEM), and distribution of the cation concentrations in the $LiNbO_3$ crystal by the secondary ion mass spectrometry (SIMS).

• Korean Journal of Food Science and Technology
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• v.35 no.4
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• pp.628-634
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• 2003

To investigate the effects of storage and pasteurization temperature on the quality of kiwi juice $(13.5^{\circ}Brix)$, the Kiwi juice was pasteurized at 65, 75 and $85^{\circ}C$ for 15 sec. The microbial, physicochemical measurements and sensory evaluations were conducted at the same condition during storage at 4 and $25^{\circ}C$ for 30 days. Most of the vegetative bacteria cells in kiwi juice were destroyed by heat treatment over $65^{\circ}C$, and they did not actively grow in kiwi juice after pasteurization. The D values of bacteria in kiwi juice by tubular type of heating exchange were 4.17, 1.47 and 0.81 sec at 65, 75 and $85^{\circ}C$, respectively. The growth of microorganisms during storage were not detected in the most samples. The amounts of vitamin C decreased as the pasteurization-storage-temperature and storage time increased. While reducing sugar increased as the pasteurization-storage temperature-storage time increased, it decreased rapidly after 20 days of storage. Hunter's color values L, a and b of stored kiwi juice were decreased at all storage conditions, browning reaction rate increased as the pasteurization-storage-temperature was decreased.

• The Journal of Korean Medical History
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• v.25 no.2
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• pp.63-96
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• 2012

The PingMaiFa chapter, which is the second chapter of SongBon ShangHanLun, is the scholarly description(專論) of the pulse and pathological mechanism but has not been studied and published yet. This study is about article 1-13 which is the first part of The PingMaiFa chapter. We compared the original texts within the editions, comparing and analyzing the annotations of successive dynastic medical group. The articles of The SongBon ShangHanLun PingMaiFa chapter 1-13 is consisted as is shown: article 1 states about the general features of normal pulse (平脈) and its physiological mechanism and the morbid pulses (病脈) caused by wind, cold, retained fluid, pain and heat vexation, article 1,10 state about the normal pulses of Five viscera (lung, heart, spleen, liver and kidney) and their manipulations in pulse taking, article 2 states about the differentiations of deficiency and excess syndrome according to pulse conditions, article 3, 4 state about the estimation of good prognoses and a factitious disorder by the combination of pulses and symptoms, article 6 states about Latent qi (伏氣) and its diagnostic features, article 5 states about inspection and listening examination as co-diagnostic methods of the pulse diagnosis, article 7, 8, 9 state that the emotions, such as fear and shame, and the dietary are important factors to consider for making diagnosis, article 11 states about the overwhelming pulse (相乘脈) which indicates the abnormal correlations between five phases and appears in four patterns as the dissolute(縱), the unrighteous(橫), the unfavorable(逆) and the favorable(順), article 12 states about 6 harmful pulses(殘賊脈), which are string-like pulse(弦脈), tight pulse(緊脈), floating pulse(浮脈), slippery pulse(滑脈), sunken pulse(沈脈), rough pulse(澁脈), article 13 states about "JaeGoe"(災怪) which is an unexpected response after treatment and it comes because of the formulas that had before. Throughout all these articles, The PingMaiFa chapter not only offers great value for Pulse-taking diagnosis, but also leads to a better understanding of clinical applications.

• Current Research on Agriculture and Life Sciences
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• v.16
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• pp.45-54
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• 1998

A thermotolerant bacterium, Streptomyces thermocyaneoviolaceus which produced xylan-degrading enzymes, utilized excellently xylan of wheat bran by producing the enzymes in comparison with that of birchwood or oat spelts. Optimal enzyme production was achieved in WB medium containing 0.8% wheat bran, 0.06% yeast extract, 0.06% bactopeptone, 0.05% $MgSO_4{\cdot}7H_2O$, 0.05% $FeSO_4{\cdot}7H_2O$, 0.05% $KH_2PO_4$ and, 0.2% $K_2HPO_4$(pH 7.0) at $50^{\circ}C$ for 24 hrs. The optimal pH and temperature for the hydrolysis of xylan were pH 5.5 and $65^{\circ}C$, respectively. The enzyme activity was retained more than 80% at the range from pH 4.5 to pH 9.5 at $4^{\circ}C$ for 12 hrs and 94% on the heat-treatment at $65^{\circ}C$ for 1 hr. Xylobiose, xylotriose, xylose, and other xylooligosaccharides were produced as end products from hydrolysis of birchwood xylan by the xylanase of S. thermocyaneoviolceus.

• Applied Chemistry for Engineering
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• v.30 no.3
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• pp.331-336
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• 2019

In this study, required properties and optimized procedure conditions for the pitch based soft carbon anode of lithium ion battery was investigated for improving the initial efficiency and rate performance. Each petroleum residue was thermally treated at 360, 370, and $410^{\circ}C$ for 3 hours to synthesis a pitch and the corresponding pitch shows the softening point of 86, 98, and $152^{\circ}C$, respectively. The elemental analysis and thermal characteristics of the pitch were investigated by EA analysis and TGA. It was noted that the low H/C and improved thermal stability were obtained with the high softening point. The obtained pitch was carbonized at $1,200^{\circ}C$ for 1 hour to produce a soft carbon based anode. As a result of investigating the crystal structure by XRD analysis, it was found that the crystallinity of soft carbon increased with increasing the softening point. It was considered that relatively higher boiling components and decreases in the evaporation component resulted the components participation for cyclization during the heat treatment process. The soft carbon based anode with an improved crystallinity shows the enhanced initial efficiency and rate performance. The mechanism of both improvements was also discusssed based on the developed crystal structure of soft carbon based anode materials.

• Composites Research
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• v.31 no.6
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• pp.385-391
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• 2018

In this study, carbon fibers were fabricated via carbonization of oxidized polyacrylonitrile (oxi-PAN) under different carbonization conditions. Carbonization of oxi-PAN fiber was performed under four different temperature (1300, 1400, 1500, $1600^{\circ}C$) with four different fiber tensions (14, 25, 35, 45 MPa). Effect of carbonization process on the structural development and mechanical properties of carbon fiber were characterized by single filament fiber tensile test and Raman spectroscopy. A clear correlation exists between the Raman spectrum and the tensile modulus of carbon fiber and effect of carbonization temperature on the tensile modulus showed increased tendency only at higher fiber tension (${\geq}25MPa$) while tensile strength showed decreased or random tendency. Therefore, it may be concluded that the optimization of carbonization temperature of oxi-PAN fiber also requires optimization of fiber tension.

• Resources Recycling
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• v.31 no.2
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• pp.40-48
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• 2022

In this study, the effects of solution components were investigated in the recovery of vanadium as ammonium metavanadate from vanadium-ore-salt roasting-water leaching solution. The vanadium-containing solution is strongly alkaline (pH 13), so the pH must be lowered to 9 or less to increase the ammonium metavanadate precipitation efficiency. However, in the process of adjusting the solution pH using sulfuric acid, aluminum ions are co-precipitated, which must be removed first. In this study, aluminum was precipitated in the form of an aluminum-silicate compound using sodium silicate, and the conditions for minimizing vanadium loss in this process were investigated. After aluminum removal, the silicate was precipitated and removed by adjusting the solution pH to 9 or less using sulfuric acid. In this process, the concentration and addition rate of sulfuric acid have a significant influence on the loss of vanadium, and vanadium loss was minimized as much as possible by slowly adding dilute sulfuric acid. Ammonium metavanadate was precipitated using three equivalents of ammonium chloride at room temperature from the aluminum-free, aqueous solution of vanadium following the pH adjustment process. The recovery yield of vanadium in the form of ammonium metavanadate exceeded 81%. After washing the product, vanadium pentoxide with 98.6% purity was obtained following heat treatment at 550 ℃ for 2 hours.