• Korean Journal of Food Science and Technology
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• v.33 no.1
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• pp.89-93
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• 2001

The quality characteristics of doenjangs added with squid internal organs were evaluated. The contents of moisture, salt and amino type nitrogen were similar among traditional doenjang and squid doenjang(I, II, III). But the color values were different. pH and peroxide value(POV) were high in squid doenjangs. Squid doenjang(I, II, III) contained much taurine($53.26{\sim}170.90\;mg%$) and ${\alpha}-aminobutyric$ acid($35.17{\sim}151.00\;mg%$) which were not detected in traditional doenjang. Also aspartic acid and glutamic acid related to palatable taste, threonine, serine and proline related to sweet tastes were much more in squid doenjangs. Contents of isoleucine and leucine related to bitter taste were similar with traditional doenjangs. Comparing with traditional doenjang, volatile flavor components in squid doenjangs had high ratio of esters such as ethylbutylether and aldehydes such as 2-propanal, 3-methylbutanal in contrast with low alcohols. Especially ethylbutylether, 2-propanol, 3-methyl-1-butanal, 2,6,10,14-tetramethyl-pentadecane, ethyllinoleate were only in squid doenjangs. From the sensory evaluation after 4 weeks, squid doenjang(II) added with 10% squid internal organs obtained the highest scores for taste as differing from traditional soybean paste and squid doenjang(I). But the total acceptability was higher in traditional doenjang because of strong fishy smell and dark color in squid doenjang. After 8 weeks squid doenjang(I, II) obtained high scores for taste and low scores for color and flavor.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.1
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• pp.97-102
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• 2008

For the use of salmon frame in zero emission, the snack using residues of salmon Gomtang was prepared and investigated on the food component characterization. According to the results of volatile basic nitrogen, water activity and sensory evaluation, the optimal substitution ratio of residues was 15% based on the mix. Total amino acid content was higher in the snack (14.8 g/100 g) with 15% residues than in snack (9.8 g/100 g) without residues. The major amino acids of the residues-added snack were aspartic acid (9.9%), glutamic acid (14.7%) and proline (9.5%). The snack with 15% residues were enriched in the mineral (calcium and phosphorus) and polyunsaturated fatty acid (20:5n-3 and 22:6n-3) compared to those of snack without residues.

• Journal of Korean Society of Forest Science
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• v.76 no.1
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• pp.33-40
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• 1987

Simulated acid rain (pH 4.0, pH 2.0) containing sulfuric and nitric acid in the ratio of 60:40 (chemical equivalent basis) diluted with underground water, and underground water (pH 6.5) as control were treated on potted Pines koraiensis seeds during the growing season (May 1 to August 31) in 1985. The regime of artificial acid rain, in terms of spray frequency and amount per plot, was simulated on the basis of climatological data averaged for 30 years of records. The seedling growth, contents of chemical substances in needles and chemical properties of the tested soil were compared among the various pH levels of acid rain on October 31, 1985. Following results were obtained. 1. With decreasing pH levels of acid rain, S and $K_2O$ contents in leaf tissue were increased, but MgO and $P_2O_5$ contents were decreased. 2. Soil pH was dropped, and exchangeable aluminum content in the tested soil was dramatically increased as the pH levels of acid rain decreased. 3. Exchangeable calcium, magnesium, potassium contents, and base saturation degree of the soil were significantly decreased with decreasing pH levels of acid rain. 4. Sulfate concentrations in the soil were significantly increased as rain pH decreased, but total nitrogen and available phosphate contents were not influenced by acid rain.

• Journal of Korean Society of Forest Science
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• v.99 no.3
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• pp.432-438
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• 2010

This study was carried out to understand the effect on soil chemical property, ion contents, and growth of Lonicera japonica by treatment of simulated acid rain and wood vinegar. It was treated total 30 times by one time per 2 weeks during 150 days from June to October dividing to various pH level of simulated acid rain (each pH 5.6, 4.5, 3.5 and 2.5) and the control site (pH 6.3). The wood vinegar diluted with 500 times was also treated total 10 times by one time per 2 weeks at the experimental sites. The soil pH was reduced as pH level of simulated acid rain was decreased. The organic content, total nitrogen, and Av. $P_2O_5$ in soil showed a tendency to increment. However, the soil improvement effect was exposed to be insufficient when a wood vinegar was treated. In the component of the plant body, $SO_4{^2}$ and $NO_3{^-}$ increased due to the simulated acid rain treatment and the increment ratio was reduced in the wood vinegar treatment plot. In addition, the cation contents showed a tendency to variation due to pH of simulated acid rain. And it showed more increment in the leaves than the root. The early fallen leaves and growth inhibition of L. japonica showed up after the simulated acid rain treatment but the growth of L. japonica increased after the wood vinegar treatment.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.20 no.1
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• pp.1-6
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• 2010

CuInGaSe(CIGS) mixed-source was prepared by hydride vapor phase epitaxy (HVPE). Each metal was mixed in regular ratio and soaked at $1090^{\circ}C$ for 90 minutes in nitrogen atmosphere. After making the mixed-source to powder state, the pellet was made by the powder. The diameter of pellet is 10 mm. The CIGS thin film was deposited on soda lime glass evaporated Mo layer bye-beam evaporator. To confirm the crystallization, we measured X-ray diffraction (XRD). High intensity X-ray peaks diffracted from (112), (204)/(220), (116)/(312) and (400) of CIGS thin film and from (110) of Mo were confirmed by XRD measurement.

• Journal of the Korean Chemical Society
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• v.35 no.4
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• pp.389-396
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• 1991

The pre-concentration and determination of ultratrace arsenic in water samples was studied by the precipitate flotation technique. The arsenic in 1.0l of water sample, in which all suspended materials were filtered out, was coprecipitated together with La(OH)$_3$ precipitates at pH 8.5${\pm}$0.1. After the precipitate was made to be hydrophobic by adding mixed surfactant of 1 : 8 mole ratio of sodium oleate and sodium dodecyl sulfate, it was floated with the aid of tiny bubbles of nitrogen gas in a flotation cell. The floated precipitate was quantitatively collected on a micropore glass filter by the suction, dissolved with small volume of 1.0M sulfuric acid, and accurately diluted to 25.00ml with a de-ionized water. Total arsenic was spectrophotometrically determinated by forming silver diethyldithiocarbamate complex of arsine generated from arsenic in the concentrated solution. The calibration curve was linear up to 20ng/ml in the original solution. Analytical results showed that contents of arsenic in a campus wastewater and a river water were 8.2ng/ml and l.0ng/ml, respectively, and their recoveries were 93${\%}$ and 90${\%}$ in water samples which a given amount of arsenic was added into. From above result, it could be concluded that this method was applicable to the determination of arsenic in various kinds of water at low ng/ml levels.

• Journal of the Korean Electrochemical Society
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• v.10 no.4
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• pp.301-305
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• 2007

The performance of polymer electrolyte membrane fuel cell could be decreased due to coolant leaked from connection part. Micro pump was used to put small amount of coolant and investigate the effect on fuel cell. The stoichiometric ratio of hydrogen/air was 1.5/2.0, both side of gas was fully humidified, and current density of $400mA/cm^2$ was used as standard condition in this experiment. Constant current method was used to check performance recovery from coolant effect in 3 cell stack. The performance was recovered when coolant was injected in cathode side. On the other hand, the performance was not recovered when coolant was injected in anode side. Ethylene glycol could be converted to CO in oxidation process and cause poisoning effect on platinum catalyst or be adhered on GDL and cause gas diffusion block effect resulting performance decrease. Water with nitrogen gas was supplied in anode side to check performance recovery. Polarization curve, cyclic voltammetry, electrochemical impedance spectroscopy was used to check performance, and gas chromatography was used to check coolant concentration. Constant current method was not enough in full recovery of performance. However, water injection method was proved good method in full recovery of performance.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.4
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• pp.473-480
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• 2017

The aim of this study was to investigate the effects of gluten and moisture contents on the physical properties of extruded soy protein isolate. Extrusion conditions included various moisture (45, 50, and 55%) and gluten contents (20, 40, and 60%) at a fixed screw speed and die temperature of 250 rpm and $140^{\circ}C$, respectively. Specific mechanical energy input decreased as gluten content increased from 20 to 60%. Hydration ratio was highest ($293.23{\pm}13.68%$) at gluten and moisture contents of 20 and 55%, respectively. Lightness and yellowness increased as gluten content increased from 20 to 60% while redness decreased as gluten content increased. Color difference was the highest at low gluten and moisture contents. Integrity index was the highest ($71.15{\pm}0.93%$) at gluten and moisture contents of 60 and 45%, respectively. Nitrogen solubility index was not significantly affected by moisture content and was lowest ($22.46{\pm}1.11%$) at gluten and moisture contents of 60 and 55%, respectively. In conclusion, higher gluten and lower moisture contents were effective for texturization of soy protein isolate.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.10
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• pp.1467-1474
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• 2006

Fish-frames, which are left after obtaining fillets or muscle during fish processing, consists of useful food components, such as muscle, collagen, calcium, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). This study was carried out to prepare snack using conger eel frame (SF) for human consumption and also to elucidate food component characterization of the snack. The results of volatile basic nitrogen suggested that conger eel frame was a suitable material for preparing snack. Based on the results of sensory evaluation and costs, starch syrup was an optimal sweetener for preparing snack using conger eel frame. The starch syrup-treated SF appeared safe because the moisture content and peroxide value were below the safety limits described in the guideline of Korea Food and Drug Administration (KFDA). Starch syrup-treated SF was similar in the pattern of fatty acid composition to soybean oil, whereas EPA and DHA were detected in SF. The total content of amino acid in starch syrup-treated SF was 23.9% based on 100 g of raw material. The maj or amino acids were aspartic acid, glutamic acid, glycine and alanine. The total contents of calcium and phosphorus in starch syrup-treated SF were 4.9% and 2.8%, respectively. The Ca/P of starch syrup-treated SF was 1.9, which is a good ratio for absorption of calcium. The SF made with starch syrup was superior in EPA and DHA compositions, total amino acid, calcium and phosphorus contents to commercial snack using eel frame.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.1
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• pp.1-8
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• 1992

A 4-week energy balance study was conducted to estimate the energy expenditure (EE) of 7 high school age men, 16 to 18 year of age, by measurement of energy intakes and changes in body energy (BE) content (intake/balance technique), keeping their normal living pattern and maintenance body weight. Gross energy intake (GE) and fecal energy (FE) loss was measured by bomb calorimetry, Urinary energy (UE) loss was calculated from nitrogen excreted. Fat mass (FM) was determined from body density estimated from skinfold thickness. 1) Mean constitutional ratio of carbohydrate, protein and Int for the total energy intake was $73.7{\pm}0.3%$, $13.5{\pm}0.3%$ and $12.9{\pm}0.5%$, respectively. 2) Fecal energy loss was 2.4% proportion of the gross energy intake. 3) Mean daily metabolizable energy estimated by subtract fecal and urinary energy loss was $2582{\pm}61\;kcal$. 4) Total body energy change estimated from body composition change over 28 days was decreased $4309{\pm}1837kcal$. 5) Mean daily energy expenditure was $2736{\pm}59kcal\;(46{\pm}1kcal/kg$ of body weight).