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Study on the Latent Heat Characteristics of the Organic Compound, $C_{28}H_{58}$ and the Inorganic Compound, $CH_3COONa{\cdot}3H_2O$ (유기잠열재, $C_{28}H_{58}$과 무기잠열재, $CH_3COONa{\cdot}3H_2O$의 잠열특성연구)

  • Song, Hyun-Kap;Ryou, Young-Sun
    • Solar Energy
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    • v.11 no.3
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    • pp.53-61
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    • 1991
  • In this research, Octacosane($C_{28}H_{58}$) and Sodium Acetate Trihydrate($CH_3COONa{\cdot}3H_2O$) were selected as latent heat storage materials to store off-peak electricity or waste heat of an industrial plant. Experimental analyses were performed in terms of the variation of phase change temperature and latent heat, phase change stability for the long term utilization. The results were as follows. 1. The phase change temperatures of industrial grade Octacosane and Sodium Acetate Trihydrate were $60.7^{\circ}C$ and $57.4^{\circ}C$, the latent heat were 60.6kcal/kg and 51.1kcal/kg respectively. 2. The latent heat quantity of Octacosane was decreased with the increasing number of phase change cycles. It decreased from 60.6kcal/kg to 47.2kcal/kg upto 200 cycles and then no variation was observed after 200 cycles. 3. To prevent the supercooling of Sodium Acetate Trihydrate, the nucleating agent, Sodium Pyrophosphate Decahydrate of 3 wt% was added, and then the supercooling temperature (Tm-Tsc) was decreased from $25.7^{\circ}C$ to $1^{\circ}C$. The phase separation was disappeared by the addition of CMC-Na of 3 wt% as a thickener. It was found that the optimal quantity of nucleating agent and thickener was 4wt% considering the stability of SAT as a latent heat storage material. 4. The phase change temperature of Sodium Acetate Trihydrate($CH_3COONa{\cdot}3H_2O$) was adjusted from 57.4 to $46.2^{\circ}C$ by the addition of UREA. And then the latent heat quantity was decreased from 51.1 to 38.3kcal/kg. 5. When the heat storage capacities between the sensible and latent heat storage materials were analyzed and compared in heating process from 30 to $90^{\circ}C$, the heat storage capacity of Octacosane was 2.45 times larger than water and 12.5 times than granite at $60.7^{\circ}C$, and the heat storage capacity of Sodium Acetate Trihydrate was 2.53 times larger than water and 12.91 times than granite at $57.4^{\circ}C$.

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Studies on the Development of Natural Preservatives from Natural Products (전통식품 및 천연물에서 천연보존료 개발에 관한 연구)

  • Kim, Hee-Yun;Lee, Young-Ja;Hong, Ki-Hyoung;Kwon, Yong-Kwan;Lee, Ju-Yeun;Kim, So-Hee;Ha, Sang-Chunl;Cho, Hong-Yon;Chang, Ih-Seop;Lee, Chul-Won;Kim, Kil-Saeng
    • Korean Journal of Food Science and Technology
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    • v.31 no.6
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    • pp.1667-1678
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    • 1999
  • Certain parts of 190 kinds of medicinal herbs and 171 kinds of original materials of food were extracted by methanol. The extracts were tested their microbial inhibition activities against several food spoilage microorganisms, Micrococcus luteus, Bacillus subtilis, Bacillus cereus, Listeria monocytogenes, Pseudomonas aeruginosa, Salmonella typhimurium, Escherichia coli, Saccharomyces cerevisiae, Candida albicans, Penicillium citrinum, Aspergillus flavus and Aspergillus niger. The methanol extracts of Cornus officinalis, Evodia officinalis, Glycyrrhiza glabra, Salvia miltiorrhiza. Schizandrae fructus, Coptidis rhizoma, aroma hop and bitter hop were shown inhibitory effect on certain species of gram(+) bacteria. Aroma hop and bitter hop were shown inhibitory effect on certain species of gram(-) bacteria. The methanol extract of Salvia miltiorrhiza exhibited a strong antibacterial activities. It was purified by solvent fractionation, silicagel column chromatography, prep. TLC, prep. HPLC. The purified active substance was identified as cryptotanshinone by EIMS, $1^H-NMR,\;{13}^C-NMR$ and DEPT. Cryptotanshinone showed a strong antibacterial activity against gram positive bacteria $(MIC\;:\;3.91{\sim}62.50\;{\mu}g/mL)$. Especially, this compound was the most strong activity against Bacillus subtilis $(MIC\;:\;3.91\;{\mu}g/mL)$.

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Sprouting Characteristics and Herbicidal Responses of Purple Nutsedge (향부자 괴경의 출아특성과 제초제에 대한 반응)

  • Kim, J.S.;Shin, W.K.;Kim, T.J.;Cho, K.Y.
    • Korean Journal of Weed Science
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    • v.14 no.2
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    • pp.120-127
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    • 1994
  • To establish an efficient herbicide screening method for purple nutsedge(Cyperus rotundus) control, its sprouting characteristics, tuber production and responses on several herbicides were investigated under greenhouse condition. The tubers stored at $4^{\circ}C$ after sterilization with the diluted prochloraz(Spotac) solution showed higher sprouting than the non-sterilized did. The harvested tubers were not dormant, and the sterilized tubers which stored at low temperature had a sprouting capability of about 80% after 6 months. If the fresh weight of purple nutsedge tubers was decreased to below 48%, they could not sprout. However, the tubers soaked in water and then stored at low temperature could sprout by 88% even 6 months later. Sprouting and initial growth of tuber were much better at $35^{\circ}C$-day/$25^{\circ}C$-night than at 30/$20^{\circ}C$ or 25/$15^{\circ}C$. The half-sected tubers, which were prepared by setting the intact tuber of above 1.2g latitudinally, were shown similar initial growth to the intact but those sected crucifically were not. These results suggest that the half-sected tuber itself can be used as a material on herbicide screening. About 1000 tubers could be harvested when 10 tubers planted in a pot($56{\times}35{\times}16cm$) filled with the artificial soil were cultivated in greenhouse of $35^{\circ}C$-day/$25^{\circ}C$-night for 3 months(April-July, 1993). Chlorimuron, Bentazon and Norflurazon were selected as the standards for the screening because of providing relatively effective control on purple nutsedge in both soil-surface and foliar spray treatment.

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Studies on Germination Characteristics and Differential Responses to Herbicides in Setaria Spp. (강아지풀 종류별 종자발아특성과 제초반응 차이)

  • Kim, J.S.;Kim, T.J.;Cho, K.Y.
    • Korean Journal of Weed Science
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    • v.16 no.3
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    • pp.187-193
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    • 1996
  • To supply seeds with a good quality as plant materials for herbicide screening and to know whether the germination characteristics could be associated with a differential response to herbicides, germination characteristics and differential responses to herbicides were investigated with 3 species of a genus Setaria ; Yellow foxtail(Setaria glauca P. Beauv, SETGL), Giant foxtail(Setaria faberi Hetrm, SETFA), and Green foxtail(Setaria viridis P. Beauv, SETVI). Degree of dormancy was high in the order of SETGL, SETVI and SETFA. The dormancy of SETGL seed was relatively well removed by room temperature and drying storage, but SETFA and SETVI by low temperature and wetting storage(stratification). For breaking dormancy of SETGL, SETVI and SETFA, it was necessary for being kept under the above storage conditions for at least 2, 4 and 4-5 months, respectively. When the dormancy-breaked seeds were transfered to low temperature($4^{\circ}C$) and drying condition, SETGL showed germination rate of 96% even after 2 month storage. However, SETVI and SETFA showed a decreased germination of 54% and 69%, respectively, with a decreased velocity of germination, indicating that secondary dormancy might be induced. On the other hand, a significant change in germination rate was not observed as the seeds were transfered to room temperature($25^{\circ}C$) and drying condition. The germinability of SETGL seed began to decline from 6th year after storage in room temperature and drying condition. All of 3 species showed relatively high germination rate at alternating temperature of $30^{\circ}C$/$20^{\circ}C$(14hr/10hr) and their germination were not increased by light. All of 3 species exhibited similar responses to cycloxydim, sethoxydim and primisulfuron in greenhouse experiment. In contrast, SETVI and SETFA were relatively susceptible to fenoxapropethyl, SETFA to fluazifop-butyl, SETGL and SETFA to clorimuron-ethyl, and SETGL to EK-2612. The difference in herbicidal response among 3 species was the highest in the treatment of EK-2612. These results suggest that there is no a consistent tendency in responses of 3 species to herbicides which have the same target site. And the relationship between germination characteristics and differential responses to herbicides was not found.

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Effect of Storage Conditions on the Dormancy Release and the Induction of Secondary Dormancy in Weed Seeds (저장조건이 잡초종자의 휴면타파와 이차휴면 유도에 미치는 효과)

  • Kim, J.S.;Hwang, I.T.;Cho, K.Y.
    • Korean Journal of Weed Science
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    • v.16 no.3
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    • pp.200-209
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    • 1996
  • It is assumed to be an efficient method for keeping a germinability of weed seeds as long as possible, if a secondary dormancy is not induced by transferring the seeds of which dormancy was broken in wetting condition into drying condition. To investigate its validity, two experiments were carried out on seeds of 9 weed species ; to find out the most effective storage condition in breaking the dormancy of each weed species and to know whether there is a decrease in the germinability by transferring into drying storage condition. The dormancy of Chenopodium album and Stellaria aquatica was released well under the drying condition, but that of Echinochloa crus-galli var. oryzicola by soaking in water. Other weed species were released from dormancy by storage in wetting condition. When the seeds stored in the wetting or soaking condition, are air-dried and then restored at room or low temperature, a decreasing tendency of germinability which might cause a trouble in using them practically, was not observed except on the seeds of Persicaria vulgaris. In the case of Persicaria vulgaris, the low germination since 3 month-storage seemed not to be caused by drying, because a decrease of its germinability was observed with increasing storage period in all of the storage conditions. In contrast, high germination was induced as the seeds of Echinochloa crusgalli var. oryzicola, which were not germinated during the storage in low temperature and wetting condition, were transferred into the room temperature and drying condition. These results suggest that this approach can be one of the efficient methods for keeping a good germinability as long as possible in most weed seeds.

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A Study on Middle School Students' Satisfaction and Need for Clothing section of Home Economics in the Textbook (의생활 영역에 대한 중학생의 수업만족도 및 필요도에 관한 연구)

  • Kang Mi-Hyang;Oh Kyung-Wha
    • Journal of Korean Home Economics Education Association
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    • v.18 no.2 s.40
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    • pp.63-77
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    • 2006
  • The Purpose of this study is to provide the basic data for the improvement or the contents or clothing curriculum in the 7th technology home economics of middle school. The standard of satisfaction of students' according to the detail domains and the standard of necessity and practical use and learners' patterns of activity task suggested in textbooks were evaluated. The ninth grade 169 boy students and 336 girl students in the national capital region were participated in this survey. According to the survey results, firstly, a dress domain got the highest relative importance(28.56%) while a clothes material domain took the lowest relative importance(8.07%) among various detail domains. Secondly, the standard of satisfaction according to each detail domain fell below the average. Generally girls' satisfaction for teaching was higher than boys'. Thirdly, a clothes material domain showed the lowest necessity for textbook contents according to detail domain and other domains showed above the average. The necessity for textbook contents appeared high for boy students rather than girl students. In addition, boy and girl students did not have interest in content relevance in textbook. Especially, they could not do well and understand experiments and practices in clothing section. Finally, The degree of utilization of the activity task ill textbooks was very low. Among various activity tasks, the learning by discovering and exploring were more utilized than cooperating learning.

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The Development and Its Application of Teaching-Learning Plan in Food and Nutrition Area by Using Reading Education (독서교육을 이용한 식생활 단원 수업의 교수-학습 지도안 개발 및 적용)

  • Han, Ga-Eun;Yoo, Ji-Yeon;Jung, In-Kyung;Kim, Jung-Hyun
    • Journal of Korean Home Economics Education Association
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    • v.20 no.4
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    • pp.125-137
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    • 2008
  • The purpose of this study was to improve the interest of food and nutrition area in Technology Home Economics subject as well as food safety and choice. For that, we developed new teaching-learning plan by using reading education method and applied to the 9th grade students in Buchun, Kyunggi-do. Experimental and control groups were selected based on their test score in nutrition section. Control and experimental groups were educated by general lecture or reading education method for 4 weeks and the effect of different educational methods was tested. The results of study as follow: First, teaching-learning plan by using reading education method has been developed. To apply reading education method, we developed reading record cards which could help students to understand the terminology and nutritional problems. In addition, students had time to discuss about food safety and choice after reading education which could improve the interest in Technology Home Economics subject and communication skills. Second, after applying the developed lesson plan, the results showed that reading education method improved the interest and attitude about Technology Home Economics subject and teacher, and food choice attitude. However, reading education method had no effect on the interest on reading book about food and nutrition, and These results suggested that reading education method improved the interest and recognition about Technology Home Economics subject and teacher and food choice attitude. Therefore, to establish the proper dietary behavior in junior high school students, we need to develop and apply diversity of teaching-learning plan by using reading educational method.

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Assessment of Sensory Attributes and Safety of Cook-Chilled Buchu-jeon (Cook-chill 부추전의 관능성 및 안전성 평가)

  • Lee, Kyung-Eun;Lyu, Eun-Soon;Jeong, Dong-Kwan
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.34 no.6
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    • pp.850-856
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    • 2005
  • The sensory and safety of cook-chilled Buchu-jeon were evaluated to provide to foodservice operation during chilled storage for 5 days. The sensory evaluations of cook-chilled Buchu-jeon were conducted according to 3 reheating methods which was frying pan, steam/convection oven and microwave oven. The sensory evaluations were made on 4 sensory attributes (taste, odor, color, and texture) by a 9-member panel using quantitative descriptive analysis (QDA). The Buchu-jeon reheated in the steam/convection oven, after 1 day storage at $3^{\circ}C$, obtained higher score in taste, odor and texture than the ones reheated in a frying pan and microwave oven. Three reheating methods didn't show any difference in taste, odor, color, and texture of Buchu-jeon at $3^{\circ}C$ for 3 days. The Buchun-jeon reheated in microwave oven at $3^{\circ}C$ for 5 days had a significant $(p\leq0.05)$ lower score odor and color than the ones reheated in frying pan and steam/convection oven. The safety of Buchu-jeon was also evaluated by measuring total count, coliform count, psychrotrophic count, acid value and peroxide value during 5 days of storage periods at $4^{\circ}C$C. Total counts of Pajeon was ranged from $5.0\times10^{1}$ CFU/g to $2.2\times10^{2}$ CFU/g and the coliform and psychrotroph were not detected at most experiments. The acid values were ranged from 1.80 to 2.18 mg of KOH/g of fat until 5 days at $4^{\circ}C$. And the peroxide values were ranged from 4.44 to 17.87 meq of peroxide/kg of fat until 5 days of storage period. Therefore, these results demonstrated that the cook-chilled Buchu-jeon is microbiologically and chemically safe during 5 days of storage period at refrigeration temperature.

Food Safety Knowledge and Home Food Safety Practices of Home-delivered Meal Service Recipients (가정배달 노인급식 수혜자의 위생지식 및 가정에서의 위생관리 습관)

  • Lee, Kyung-Eun;Yi, Na-Young;Park, Jung-Yeon
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.38 no.5
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    • pp.618-625
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    • 2009
  • The purposes of this study were to evaluate food safety knowledge and to assess home food safety performance of home-delivered meal service recipients. Two facilities providing home-delivered meal services for older adults were located in Seoul. A total of 120 service recipients were surveyed using an individual interview technique and 97 responses were used for data analysis. A statistical data analysis was completed using SPSS program (ver.14) for descriptive analysis, t-test, ANOVA, and correlation analysis. The majority of the participants were 70 years old or older and females. They perceived their health status as poor or very poor and took more than one kind of medicines. An average score of the food safety knowledge test was 11.48 based on 18 points (63.8%). The results revealed that the older adults knew the importance of hand washing but were not aware of when and how to wash hands. There was room to improve knowledge on cleaning and sanitizing fresh fruits and using wiping cloth. The knowledge score for each category was not significantly different by gender and age. The home food safety practices of the older adults was rated as 2.8 out of 4 points; the highest score was associated for proper food handling category and the lowest score was for cleaning and sanitizing. The worst performance was related to managing hand cuts and wounds (1.96). The total knowledge score and an average performance score were significantly correlated (p<0.01). Food safety education programs targeting the older adults who receive home-delivered meal services would improve the recipients' food safety knowledge and practices related to consumption of the meals at home. The programs should focus on not only improving food safety knowledge but also changing food safety practices.

Anti-atopic Effects of Castanea crenata Inner Shell Extracts Fermented by Lactobacillus bifermentans (Lactobacillus bifermentans로 발효한 율피의 항아토피 효과)

  • Kim, Bae Jin;Son, Woo Rim;Choi, Mi Ok;Jo, Seung Kyeung;Jung, Hee Kyoung;Lee, Jin Tae;Kim, Hak Yoon;Kwoen, Dae Jun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.42 no.9
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    • pp.1378-1386
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    • 2013
  • Atopic dermatitis (AD) is a common skin disease characterized by chronic and relapsing inflammatory dermatitis with immunological disturbances. In spite of the continuous increase in the incidence of AD, it is regrettable that till date there is no effective treatment to treat the same. Therefore, the present study was designed to examine the possible anti-atopic effects of Castanea crenata inner shell extracts fermented by Lactobacillus bifermentans (FCS) in 2,4-dinitrochlorobenzene (DNCB) induced AD in NC/Nga mice. Based on the results of HPLC analysis, we found that FCS contains anti-inflammatory factors such as gallic acid (10.18 mg/g) and ellagic acid (2.14 mg/g). The groups that we have used in this study included 0.1%, 1%, 5% fermented Castanea crenata inner shell extracts (FCS 0.1, FCS 1, FCS 5), 1,3-butylene glycol treated control (AD), and normal mice. After topical FCS treatment, we observed that the clinical severity score for AD was lower in both the FCS 1 and FCS 5 groups than the AD group. We also proved beyond doubt that there was improvement of melanin, erythema and skin moisture indices in the FCS 5 group. Spleen index and gene expression levels of pro-inflammatory cytokines such as IL-$1{\beta}$ and TNF-${\alpha}$ were significantly decreased in the FCS 5 group compared to the AD group (P<0.05). Further, we also found that the level of serum immunoglobulin E (IgE) in the FCS-treated group was decreased in a concentration-dependent manner. The results of our study suggest that FCS can be effectively used as a cosmeceutical ingredient for both the prevention and improvement of AD.