• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.5
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• pp.426-430
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• 1994

To establish the proper size of seedling of A. gigas, different weight of seedlings were used for this study. Agronomic characters including plant height, number of leaf, leaf length, number of inflorescence, fresh weight and rate of bolting of the aerial parts, root length, root diameter, number of lateral root and root weight of the underground parts were determined and correlation coefficients among them were estimated. Growth of A. gigas showed the significant vigor for all the characters of the aerial parts along with increasing of seedling weight, but root weight in yield decreased in proportion to increasing of seedling weight due to lignification of the root tissue. When the smaller seedlings were transplanted, bolting rates decreased to about 16% as compared with the traditional size of seedlings. Correlation coefficients between aerial and root characters in A. gigas were negative, and the characters such as plant height, number of leaf, number of inflorescence and fresh weight per plant showed highly significant correlation with the rate of bolting which is one of the characters having great influence on yield.

• Korean Journal of Agricultural and Forest Meteorology
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• v.4 no.1
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• pp.29-37
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• 2002

This study was conducted to compare ozone sensitivity among Betula sp. by measuring visible foliar injuries and growth responses. Four Betula sp.(B. costata, B. davurica, B. platyphylla var.japonica and B. ermani) grown in the greenhouse, were transplanted in the plastic pots. One-year-old seedlings of four Betula sp. exposed to relatively high ozone concentration(100 ppb) for 8 h day$^{-1}$ for 5 weeks in fumigation chamber. We measured visible injuries, leaf numbers and leaf areas at the end of experiments, and growth effects were evaluated by measuring the relative growth rate(RGR) of height and diameter and the dry weights of leaf, stem and root once a week. Four Betula species showed the significant differences for growth responses by the ozone treatment. Growths of three species, except for B. ermani, were significantly reduced by the $O_3$ exposure. B. costata with leaf senescence at the early growing stage and B. davurica indicated highest visible foliar injury rate may be the sensitive species at the 100 ppb ozone concentration. Although the growth rate of B. ermani was reduced by 100 ppb ozone exposure at the early growing stage, B. ermani may be a tolerance species that recover the growth rate with the adaptation for the high ozone concentration.

• Journal of the Korean Society of Food Science and Nutrition
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• v.31 no.2
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• pp.221-224
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• 2002

This study was to explain the properties of acorn sediments and characteristics in the texture of acorn mooks due to the differences in preparing conditions of acorn sediments. The hardness of mook increased at 4$^{\circ}C$ during storage. The increase rate of acorn mook's hardness after storage for 24 hrs at 4$^{\circ}C$ were higher than those of others. X-ray diffraction of the retrograded acorn mooks was little different during storage at 4$^{\circ}C$. The syneresis of acorn mook was decreased with increasing the soaking treatment. The syneresis (%) of nontreated sample (0-0) was larger than those of the others.

• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 2003.10a
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• pp.182-182
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• 2003

1.연구목적 : Cr $O_3$은 금속 도금용, 페인트 둥에 많이 사용되며 독성이 강하여 그동안 근로자 건강장해 및 직업병 사례가 많이 발생하였다. 그러나 산화크롬의 흡입에 의한 연구자료는 매우 부족하다. 이에 흡입챔버를 이용 Rats에 흡입노출을 통하여 유해성을 평가하고 각 장기에 흡수되는 크롬의 농도평가와 회복기간에 따라 각 장기별로 흡수된 크롬의 소실속도 둥을 연구하였으며 더불어 회복기간과 제거율의 상관관계 및 체내 반감기 등을 연구하였다. 2. 연구방법 : Cr $O_3$를 폐내 침착율 및 흡수율이 높은 0.5～5$\mu\textrm{m}$ 크기의 aerosol형태로 SD Rats 수컷에 전신폭로 하였다. 노출농도는 0.00, 0.20, 0.50, 1.25mg/㎥(Cr)으로 하여 1일 6시간, 주 5일, 13주간 반복 노출하였고 회복군은 시험물질 종료일을 기준으로 2주, 8주 경과 후 조직장기와 전혈, 혈장 및 적혈구내, 뇨 중 각각의 크롬농도를 분석하였으며 혈액 및 혈액 생화학적 검사도 병행하였다 3. 연구결과 : 혈액검사에서 0.20, 0.50 mg/㎥ 농도군 실험동물의 RBC와 HGB, HCT 둥은 감소의 경향을 보였으나 농도 의존적이지는 않았다. 신장의 절대중량은 대조군에 비해 유의하게 (p<0.05) 감소하고 폐장의 경우는 대조군에 비해 유의한(p<0.05) 절대중량 증가를 보였다 시험물질 노출 후 혈액 중 전혈, 혈장, 적혈구의 회복기간(x)별 크롬농도(y)의 소실속도 상관계수 (노출농도 0.50mg/㎥군의 경우)는 y = 66.51 $e^{0.057}$x/, y = 67.2 $e^{0.101}$x/, y = 70.01 $e^{0.030}$x/, 반감기는 12.0, 6.86, 23.0 일이고 폐장, 간장, 신장의 회복기간(x)별 크롬농도(y)의 소실속도 상관계수 (노출농도 0.50 mg/㎥군의 경우)는 y = 1808 $e^{0.004}$93x/, y = 12.02 $e^{0.029}$7x/, y = 67.61 $e^{0.029}$2x/ 반감기는 140.6, 23.3, 23.7 일로 평가되었다. 4. 고찰 : 실험동물의 전혈, 혈청, 뇨에서의 크롬농도와 시험물질 노출농도는 밀접한 상관을 가졌으나 농도에 정비례하지는 않았다. 뇨 중 흡수된 크롬의 경우 회복기간 초기 (12시간 내)에 대부분 배설이 일어나는 것으로 나타났다. 폐장이 간장, 신장 등 다른 장기에 비해 높은 축적량을 보였으며 축적된 크롬농도가 높을수록 크롬의 소실속도는 현저히 저하하는 경향을 보였다. 노출농도가 높을수록 각 장기조직 내 크롬의 소실속도 (clearance)는 크게 감소경향이 있었으며 이는 체내 과부하시 자정작용이 감소하는 것으로 판단되었다. 본 연구 결과 SD rat를 이용 반복흡입노출의 경우 생체의 무유해영향농도 (NOAEL)는 0.2mg/㎥이하이며 발암물질을 감안하여 안전계수를 100으로 할 경우 사람에 대한 NOAEL은 0.002mg/㎥이하로 판단되었다. 특히 호흡기와 폐장에 강한 유해성을 나타내는 것으로 확인되었다. 것으로 확인되었다.

• Food Science and Preservation
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• v.13 no.1
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• pp.8-12
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• 2006

The effects of packaging treatments with either low density polyethylene (LDPE) or polypropylene (PP) films on the quality of leaf lettuce were evaluated. It was also stored within a plastic bag (LDPE and PP films) with 4 pelf orated holes (6mm diameter). Changes in weight loss, color difference, anthocyanin, chlorophyll, water content, and general appearance (shape of lettuce) ware investigated Total weight of leaf lettuce packaged within non-pelf orated films decreased slowly over the storage periods at 5 and $20^{\circ}C$. The weight loss of leaf lettuce showed no significant difference between non-pelf orated and perforated films at $20^{\circ}C$. General appearance in leaf lettuce stored at $20^{\circ}C$ was not significantly affected by packaging treatments with LDPE and PP films. The shelf life of non-packaged leaf lettuce at $5^{\circ}C$ was 8 days, whereas packaging treatments with LDPE and PP films showed freshness in leaf lettuce for 30 days of storage. Total chlorophyll and water contents of leaf lettuce packaged within pelf orated and non-pelf orated films decreased gradually during storage. However, no remarkable changes in color difference, levels of chlorophyll and anthocyanin, and water contents were observed in leaf lettuce packaged within perforated and non-pelf orated films. In this experiment, leaf lettuce packaged within LDPE or PP films without any punching holes at $5^{\circ}C$ was the most desirable for extending the quality. These results suggest that non-pelf orated packaging treatment in combination with low storage temperature could be effective in prolonging the shelf life of leaf lettuce

• The Korean Journal of Mycology
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• v.46 no.2
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• pp.177-185
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• 2018

The cultivation characteristics of 26 wild strains of Lentinula edodes were investigated for their use as breeding material. Strains NIFoS 68, 136, 1521, 1651, and 2064 showed an above average mycelial growth on potato dextrose agar at 10, 20, and $30^{\circ}C$. NIFoS 411 showed the lowest mycelial growth at $20^{\circ}C$, but the highest growth at $30^{\circ}C$. The rate of weight loss of L. edodes cultivated on sawdust (2 kg) ranged from 13.5 to 47.5%, with the highest rates showed by NIFoS 50 (47.5%), NIFoS 128 (34.5%), and NIFoS 54 (34.4%). Fruiting bodies were produced in nearly all (24/26) strains and productivity ranged from 3 g to 446 g/2 kg medium. Temperature was not significantly correlated with mushroom production or mycelial growth. Larger weight loss correlated strongly with fruit yield. In terms of production, NIFoS 50 (446 g), NIFoS 952 (435 g), and NIFoS 53 (421 g) were useful as breeding material. The NIFoS 667 strain was superior in terms of morphology. NIFoS 670 showed the characteristic yellowish-brown color of fruiting bodies.

• Journal of Korean Society of Forest Science
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• v.110 no.2
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• pp.244-253
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• 2021

This study aimed to investigate quality characteristics of hot-air dried persimmon during the drying period in 'Bansi' and 'Godongsi'. These cultivars were classified into four grades: 2L, L, M, and S based on the fruit weight. Weight loss, firmness, soluble solid content (SSC), and moisture contents were measured during the hot-air drying period. The weight loss significantly increased during the drying period (p<0.05), while there was no difference between cultivars. In the initial drying period, the firmness decreased due to softening during the ripening stage and increased significantly due to hardening during the water loss stage. Regardless of the cultivars, the SSC increased from 19.6% in the initial period to 55.3% at 12 days after drying. Moisture content statistically decreased in both cultivars over the whole drying period. It took 4 days and 8~10 days to produce semi-dried persimmon (45~55% moisture content) and dried persimmon (25~35% moisture content) in both cultivars. These results could be effectively used as basic data for producing high-quality semi-dried and dried persimmons using the hot-air drying method in 'Bansi' and 'Godongsi'.

• Applied Biological Chemistry
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• v.34 no.1
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• pp.14-20
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• 1991

Changes in fruit quality and some components of Unshiu orange(Citrus Unshiu Marc. Hayashi) stored at $2^{\circ}C$ in air or a controlled atmosphere(CA, $O_2$ 10%, $CO_2$ 2%) for 111 days were studied. The incidence of rot fruits was higher in air(12.7%) than in CA condition(3.9%). The appearance of the fruits was better in CA condition than in air. There was no significant difference in the weight loss of whole fruits between both storage conditions. The ratio of the flesh weight In whole fruits under CA condition was slightly lower than those in air until 62 days of storage, while it showed no rapid decrease in the later period of storage. Under both storage conditions, the Brix in the flesh increased in the early Period of storage and then decreased slowly, while the free acid contents decreased gradually during storage. In comparison with the fruits stored in air, those under CA condition showed lower total sugar content. The sugar in the flesh of the fruits is composed of sucrose, fructose and glucose. The content of total sugar as well as each sugar showed no distinct difference under both storage conditions. In the flesh of the fruits, citric acid comprised about 90% of the organic acid and malic acid the second abundant acid. During storage, the contents of citric, malic and oxalic acid decreased. Significant difference in the decreasing rate of total organic acid between both stnrage conditions was not found. From the above results, it might be considered that CA could be applied lot the storage of Unshiu orange grown on Cheju

• Applied Chemistry for Engineering
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• v.10 no.7
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• pp.1066-1072
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• 1999

The physical properties of polymer concrete were investigated for development of high-performance construction materials. Various specimens of polymer concrete were prepared using unsaturated polyester resin as the polymer-binder with the various dosage of calcium carbonate as microfiller (5~20 wt %) and fine aggregate(10~50 wt %). For the evaluation of the physical properties of polymer concretes, tests such as compressive strength, flexural strength, water absorption test, hot water immersion test, acid resistance test and pore size distribution analysis were conducted. As a result, it is concluded that compressive and flexural strengths of polymer concretes increased up to 4 times than those of conventional cement concrete. Whereas the compressive and flexural strengths of polymer concretes tested after hot water immersion, compared with those of polymer concretes tested before hot water immersion, decreased about 67%, 47%, respectively. By hot water immersion, total pore volume and porosity(%) of polymer concretes were remarkable increased due to decomposition of polymer binder. And also, it is showed that water absorption(%) and weight loss(%) of polymer concrete specimens by acid immersion, compared with those of ordinary portland cement concrete, decreased about 1/100, 1/27, respectively.

• Food Science of Animal Resources
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• v.30 no.6
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• pp.1024-1030
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• 2010

The focus of the study was to maximize the output data for Korean cuisine. This study evaluated the nutritional retention factor for different cuts of Korean beef (Hanwoo beef) subjected to various cooking methods. Five cuts (short rib, sirloin, chuck roll, tenderloin, and fore shank) of Korean Hanwoo beef were prepared and used in this experiment. Two different cooking methods (dry-heat cooking and moisture-heat cooking) were applied to each cut. The sodium contents of dry-heat cooked short rib (86.44), sirloin (76.81), tenderloin (86.65), and fore shank (85.89) decreased. Potassium contents of dryheat cooked sirloin (94.99), chuck roll (89.19), and fore shank (92.66) decreased. Calcium contents of dry-heat cooked sirloin (61.49), chuck roll (73.97), and fore shank (91.46) decreased. Iron contents of dry-heat cooked chuck roll (79.71), and tenderloin (90.79) decreased. Phosphorus contents of dry-heat cooked sirloin (87.87), and tenderloin (99.88) decreased. Mineral contents of all cuts cooked by moisture-heat decreased. Finally, the nutritional retention factor represents output data of each cooking method with yield % of each item.