• Applied Chemistry for Engineering
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• v.3 no.4
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• pp.686-693
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• 1992

In order to investigate the mechanism of dissolutin of nickel from a matte composed essentially of heazlewoodite and ferronickel, the leaching in an aqueous solution of hydrochloric was carried out at $50-90^{\circ}C$, 0.5-3.ON HCl, and with the particle sizes between $100-160{\mu}m$ and $400-500{\mu}m$. The leaching rate of heazlewoodite was much rapider than that of ferronickel, and the two components were simultaneously dissolved with different reaction rates. Within the experimental range, NiS, an intermediate, was not formed. However a possibility to form a thin layer of NiS on particle surface upon saturating the reaction mixture with $H_2S$ was not excluded. At the initial stage, the activation energy was about 10 kcal/g mol. The reaction occurred at the particle surface, and consequently the particle size decreased with time. The rate of dissoultion for nickel was linearly proportional to the concentration of HCl up to 1.0N.

• Journal of Animal Environmental Science
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• v.19 no.2
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• pp.177-182
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• 2013

We studied the possibility to produce solid fuel using cattle manure and to apply TAO (Thermophilic Aerobic Oxidation) process of solid-liquid separation fraction. The physiochemical compositions of cattle manure solid fuel chip were analyzed as water 0.12%, low calorific value 3,510 kcal/kg, ashes 11.9%, chlorine 0.82%, sulfur dust 0.5%, mercury non-detection, cadmium 1.0 mg/kg, lead 2 mg/kg, arsenic non-detection. In treating cattle manure with TAO reactor the internal temperature of the reactor was increasing higher and $50^{\circ}C$ and over was maintained after 20 hours on. The physiochemical compositions of liquids increased from pH 7.3 to pH 9.18 and EC decreased from 4.6 to 3.48 mS/cm in treating process of cattle manure with TAO reactor. COD and SCOD decreased from 16,800 to 10,400 mg/L, from 4,600 to 2,040 mg/L respectively, which showed about 38% and 56% of remove efficiency respectively.

• Journal of the Korean Society of Food Culture
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• v.29 no.6
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• pp.668-676
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• 2014

The purpose of this study was to determine anthropometric measurements, dietary nutrient intakes, simple food intake frequencies, and rates of obesity in Cambodian women. A total 186 women, aged 20-69 years, living in Kampong Spue province of Cambodia and having the responsibility to prepare family meals participated in this study. Height and weight were measured body mass index (BMI) was calculated, and one-day 24-hour recall and food frequency questionnaires were conducted. In total, 18.8% were underweight, 49.5% were normal weight, 13.4% were overweight, and 18.3% were obese according to the World Health Organization BMI standard for Asians. No significant difference in height by obesity level was determined ($p{\geq}0.05$). The mean energy intake was 1571.2 kcal/day and protein intake was 43.6 g/day. There were significant differences in protein, niacin, and vitamin C intakes by obesity level (p<0.05). The prevalence of subjects consuming vitamins and minerals less than 75% of Recommended Dietary Allowances was 73-99%. All Cambodian women consumed rice ${\geq}1time/day$. Approximately 50% of subjects reported ${\geq}1time/day$ intake frequency of bread, cookies, and chips. In total, 35% indicated no intake of beans or bean products. For intake frequencies of carbonated beverages and sports drinks, there was a significant difference by obesity level (p<0.05). These results may be very helpful to prepare nutrition education programs for Cambodian women.

• Journal of the Korean Society of Food Culture
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• v.29 no.6
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• pp.659-667
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• 2014

Fruits are good sources of vitamins, minerals, fiber, and phytochemicals, which are known to reduce serum lipids, oxidative damage, and blood pressure as well as improve blood glucose control. The purpose of this study was to estimate nutrient quality indices of fruits by carrying out a critical analysis of pre-existing methods according to their nutritional compositions. Four methods were used to assess the nutrient indices of 26 fruits, which are frequently consumed by Koreans based on the fourth Korean National Health and Nutrition Examination Survey (2009). Naturally nutrient rich score (NNR), nutrient rich food (NRF), nutrient adequacy score (NAS), and nutrient density score (NDS) were used to calculate nutrient quality indices. The Korean Nutrition Society Food Composition database of fruits based on 100 g edible portions was used. The algorithm of each method included the mean percentage of daily values (Dietary Reference Intakes for Koreans, 2010) for particular nutrients based on consumption of 1,900 kcal/day. The relative score indicated that strawberries, kumquat, and lemon had high nutrient quality indices. In addition, mango, lemon, persimmon, strawberry, apricot, and tangerine fruits are rich in antioxidant nutrients such as ${\beta}$-carotene, vitamin C, vitamin E, and selenium. However, scores of nutrient quality indices did not imply that higher scores of particular fruits are superior. We suggest moderate seasonable consumption a variety of fruits. Our results can be used as a reference for consumers when they choose fruits.

• The Korean Journal of Food And Nutrition
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• v.20 no.2
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• pp.120-124
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• 2007

The thermal degradation kinetics of alpha-, gamma- and delta-tocopherols was studied during heating at 100, 150 200 and 250$^{\circ}C$ for 5, 15, 30 and 60 min in the absence of oxygen. The tocopherols were separated by HPLC using a reversed phase ${\mu}$-Bondapak C$_{18}$-column with two kinds of elution solvent system in a gradient mode. The kinetics for degradation of ${\alpha}$-, ${\gamma}$- and ${\delta}$-tocopherols was analyzed as a function of temperatures and times. The degradation of tocopherols was described by the first-order kinetics in the absence of oxygen. The rate of tocopherols degradation was dependent on heating temperatures. The degradation rate constants for ${\alpha}$-, ${\gamma}$ and ${\delta}$-tocopherols showed an increasing trend as the heating temperature increased. The magnitude order of the experimental activation energy was ${\delta}$->${\gamma}$->${\alpha}$-tocopherol.

• Journal of The Korean Society of Agricultural Engineers
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• v.57 no.5
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• pp.81-88
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• 2015

바이오매스는 유망한 신재생 에너지이다. 바이오매스는 액체 및 기체 연료로 전 환 할 수 있고, 다양한 공정을 통해 열 및 전력을 생산시키는데 사용된다. 바이오매스 가스화 공정은 바이오매스를 일산화탄소, 이산화탄소, 수소 및 메탄으로 이루어진 합성 가스로 전환시키는 기술이다. 바이오매스를 이용한 합성 가스 생산 및 활용은 세계적으로 늘어나는 에너지 필요성을 충족시킬 수 있는 대체에너지이다. 현재, 바이오매스 가스화의 주요 원료는 목질계 우드 칩을 주로 사용하고 있지만, 일반적으로 우드칩의 경우 수분을 다량 함유하고 있기 때문에 가스화 공정을 위해서는 별도의 건조처리를 필요로 한다. 우드칩의 건조에는 많은 에너지가 소요되고, 다량의 우드칩 건조에는 시간과 기상 및 공간적인 환경에 영향을 받는다. 본 연구에서는 미건조 우드칩의 가스화 공정을 위하여 미건조 우드칩에 숯을 각각 10, 30, 50 % 비율로 혼합하여 실험을 수행하였고, 실험결과 생산된 합성가스의 CO 농도 는 숯의 비율에 따라 14.9 ~ 25.6 % 증가되는 경향을 나타내었지만, 반대로 $CO_2$ 및 $CH_4$ 농도는 감소하였다. 이에 따라 합성가스 생산을 위한 미건조 우드칩과 숯의 최적혼합비율은 약 30 %로 판단되며, 발열량은 $1285.7kcal/Nm^3$, Gas yield는 $2.3Nm^3/kg$ 로 나타났다. 이에 적절한 숯의 혼합사용은 미건조 우드칩의 직접적인 가스화에 도움이 될 것으로 사료되며, 바이오매스 건조 공정에 필요한 에너지를 절약할 수 있을 것으로 판단된다.

• Proceedings of the Korea Society of Poultry Science Conference
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• 2000.11a
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• pp.94-96
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• 2000

The experiment was conducted to determine the effects of dietary supplementation of enzyme(Endopower) into corn-soybean meal diet on the performance of broiler chicks. Three hundred sixty 3 day-old male broiler chicks(Ross) were divided into 4 groups with 3 replicates of 30 birds per replicate and assigned at random to each of four treatment groups for two energy levels(3100 and 2980 kcal TMEn/kg) with 0 or 0.1% Endopower in the diet. The body weight gain of birds fed the low energy diet with 0% Endopower was lower significantly than the other groups(P<0.05). There were no significant differences in feed intake and feed conversion rate among the treatments. The relative sizes(% B. wt) of the liver and leg muscle were not different significantly among the treatments. The breast muscle weights of the low energy diet birds were higher than those of the high ones, and those of the lower energy group with 0.1% Endopower were highest. The intesinal lengths(cm/B.wt) of low energy diet group without Endopower were lower than those of the others. No significant differences in the relative jejunum and ileum weights were found, but % duodenum weights of high energy group were higher than those of the low energy group. The villi of the ileum of birds fed corn-soybean diet without Endopower were shortened and thickened compared to those of the birds fed with Endopower diet regardless of energy level. The results demonstrated that dietary Endopower improved body weight gain reduced abdominal fats and developed intestinal villi. Therefore it can be concluded that dietary supplementation of Endopower improves nutritive value of corn-soybean diet in broiler chicks.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.16 no.2
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• pp.183-192
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• 2006

Predicting energy expenditure (EE) is important to prevent work-related musculoskeletal disorders (WMSDs). The problem to predict EE is that the standard of EE is based on western data. The authors checked average EE by job categories to provide basic data for suggesting proper work intensity for Korean workers. This study was conducted from 2003 to 2005. Study subjects were recruited from 4 car parts assembly plant, 2 car assembly plant, 2 Heavy machine manufacturing plant and 2 shipyards. Total study subjects were 515 male workers. To estimate VO2max, sub-maximal test was conducted to measure VO275%max by bicycle ergometer (Combi Co, Aerobike 75XL II). Heartbeats were recorded with heartbeat recorder (Polar Electro Co, Finland, S810) during work. EE of work was calculated by recorded heartbeat and individual regression equation which was derived from sub-maximal test. Subjects were classified into 4 industry and 8 work posture, 23 job task categories. Mean EEs (S.D.) according to industry classification (kcal/min) were 4.9 (0.7), 4.8 (0.7), 4.9 (0.7), 5.0 (0.9), and 4.0 (0.5) for Car Part manufacture, Car Assembly, Ship Building, Heavy Machinery Manufacture, and Hospital Office, respectively. The results suggest that Korean male workers of exceeding to the NIOSH criteria will be needed to plan for job rescheduling to maintain $worker^{\circ}$Øs health. Further study to establish Korean work intensity standard would be needed.

• Korean Journal of Community Nutrition
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• v.3 no.5
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• pp.739-747
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• 1998

The purpose of this study was to compare the dietary habit and nutrient intakes of Korean farmers according to their different family patterns and farming types. Food and nutrient intakes were obtained by food frequency method. The subjects(male 35%, female 65% : mean age, $48{\pm}11 years)$ were compared 46% of nuclear family, 59% of 3-4 person of family size ; 50% of middle-scale farming ; 54% of rice farming. Sixteen percent were over 60 years old group. In aspects of dietary habit, farmers of medium size farming and 10-20 years of farming experience frequently skipped meals. But their appetite was better than small farm famers. Dinner irregularity was more frequent in their group of 3-4 person families. The numbers of food intake were significantly different according to family pattern. Nuclear family groups consumed more kinds of foods. The mean energy intake was 2000Kcal/day, with PFC ratio of 19 : 16 : 65. The energy and nutrient intakes showed the same tendency as the food variety. Intakes of calcium and iron were lower than the Korean RDA. Families with over 5 people consumed higher amounts of protein and minerals. Intakes of thiamin, niacin, and vitamin E were better in large families and large-scale farming groups. As compared with the PMS ratio, the level of monounsaturated fatty acids as higher than saturated FA. The lipid intake was also better in large families and large-scale farming. The results suggest that dietary habit and nutrient intakes were different by family pattern and farming types.

• Korean Journal of Community Nutrition
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• v.7 no.1
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• pp.102-110
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• 2002

Cigarette smoking has long been recognized as a major risk factor in the development of coronary heart disease. Several investigators have reported the strong association between smoking and high serum cholesterol, triglyceride concentration, SFA and low HDL cholesterol, PUFA and $\omega$6 concentrations. Therefore, this study was done to investigate the effect of smoking on the serum lipid profile and fatty acid composition of college women. Sixty-one non-smokers and twenty-seven smokers were selected from college women students in the Seoul area. Their lipid intake, serum lipid concentration and fatty acid composition were examined. There were no differences in the general characteristics and anthropometric indices between the smokers and non-smokers. However, alcohol consumption was significantly higher in smokers than non-smokers (p<0.001). The daily caloric intake of smokers and non-smokers were 1875.84 kcal and 1915.53 kacl, respectively. On the other hand, the mean daily intake of lipids and cholesterol were significantly lower in smokers (p<0.05). In smokers, the mean concentrations of serum total cholesterol, LDL-cholesterol and the LDL-C/HDL-C ratio were higher, and the compositions of EPA and DHA were lowe than in non-smokers. There was a negative correlation between the serum triglyceride and PUFA levels in the two groups. Also, serum HDL-C correlated negatively with MUFA in smokers and non-smokers (p<0.01). These results suggest that smoking cause inadequate changes in serum lipid profile and serum fatty acid composition, thereby increasing the tendency for coronary heart disease.