• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.161.1-161
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• 2003

본 시험은 곶감건조초기의 높은 습도로 인한 불량환경을 극복하고 고품질의 우수한 곶감을 생산하기 위하여 현재 국내에서 가장 많이 재배되고 있는 상주둥시와 갑주백목 품종을 사용하여 수행하였고, 저장을 통하여 곶감의 건조시기를 달리한 다음 곶감을 제조하여 상품성을 비교하였다. 저장에 따른 품종별 과중변화는 저장 30일에 품종별로 0.32~0.38%의 무게감소를 나타내었다. 과실의 경도는 저장 30일에 두품종 공히 2.3kg/$\Phi$5mm로 나타나 저장기간이 증가할수록 감소하였지만 이러한 경도의 감소는 곶감을 제조하기 위한 박피작업에는 무리가 없었다. 저장중에 발생한 비상품과는 저장 30일에 품종별로 3.2~4.2% 발생되었고 과실의 당도는 수확시와 비교하여 약간 감소하는 경향이었으며, 과실표면의 색도 역시 적색도는 약간 증가하였으나 유의성은 없었다. 곶감 건조중 무게변화는 박피 2주경에 대부분 박피시 중량보다 30~40%감소되었고 그 후는 완만하게 감소되어 처리 6주후에는 박피중량의 30% 이내로 되었다. 품종별로는 대과종인 갑주백목의 중량감소가 다소 늦었다. 박피시기가 늦을수록 감의 건조속도도 완만하여 30일 저장한 처리구는 박피후 8~9주에 건조가 완료되었다. 곶감 제조중 품종별 경도의 변화는 건조 1주후에 품종별로 0.38~0.42kg/$\Phi$5mm로 급격히 감소하였다가 건조 후기로 갈수록 다시 증가하여 건조 6주후에는 1.52~1.85kg/$\Phi$5mm나타났다. 곶감 제조후 상품성에 있어서 곶감의 당 함량은 수확직후 제조한 곶감이 저장한 후 제조한 곶감과 비교하여 약간 높은 경향이었으나 큰 차이는 없었다. 가용성 탄닌의 함량은 곶감 제조후 품종별로 0.7~0.9mg/g으로 나타나 떫은맛이 완전히 제거되었고 저장기간별로는 차이를 보이지 않았다. 곶감의 외관상 상품성을 나타낼 수 있는 색도는 박피시기가 늦어질수록 두 품종 공히 증가되었다. 특히 갑주백목 품종의 경우 수화직후 8.4인 적색도가 저장 30일후 13.2로 증가되었고 황색도도 13.5에서 33.1로 증가되어 곶감표면의 색도가 박피시기를 연장함으로써 크게 향상된 것으로 나타났다.

• Journal of Nutrition and Health
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• v.18 no.4
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• pp.328-336
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• 1985

식이 중 지방함량이 성장기 뇌의 미토콘드리아 지방산 조성에 미치는 영향을 살펴보기 위해 옥수수기름을 각각 10, 2, 0.5% 포함한 3종류의 식이를 임신한 Sprague Dawley종의 흰쥐에게 임신말기부터 제공했다. 수유기간 중의 영향을 살펴보기 위해 대조군(10%옥수수기름 섭취)의 일부에 분만 후 0.5% 결핍식이를 섭취시켰고, 또 이유후부터 0.5% 결핍식이군의 일부에 10% 정상식이를 주어 회복효과를 관찰하고자 하였다. 전 실험기간 동안 체중과 뇌 무게, 단백질 함량을 측정하였고 뇌에서의 미토콘드리아를 분리하여 지방산 조성을 관찰하였다. 출생후 수유기간 동안에는 대조군에 비해 지방결핍식이군에서 체중과 뇌의 무게가 다소 높았으나 이유 후 부터 점점 감소하여 유의적인 차이를 볼 수 없었고 특히 0.5% 식이군의 체중은 생후 6주와 7주에 유의적인 감소를 보였다. 그러나 체중에 대한 뇌무게와 뇌의 단백질 함량에 있어에는 대조군과 결핍군 사이에 유의적인 차이를 볼 수 없었다. 따라서 지방결핍이 뇌 성장에 미치는 영향은 다른 영양소에 비해 크지 않음을 알 수 있었다. 뇌 미토콘드리아의 지방산 조성은 나이와 식이에 따라 변하였다. 나이를 먹음에 따라 단쇄 포화 지방산은 감소하고 다 불포화 지방산의 함량은 증가하였다. 또한 결핍식이군과 대조군 사이에 뇌 미토콘드리아 지방산조성을 살펴 본 결과 지방 결핍의 좋은 지표가 되고 불포화도, triene 과 tetraene의 비, 그리고 ${\omega}-6$ 계열과 ${\omega}-9$ 계열의 비에 있어서 큰 차이를 볼 수 있었다. 이들로 부터 성장초기에 지방함량을 조절한 식이에 의해 뇌 미토콘드리아 지질 조성이 크게 변하고 이에따라 미토콘드리아의 기능도 유의적인 영향을 받고 있음을 알 수 있었다.

• Korean Journal of Materials Research
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• v.7 no.11
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• pp.957-963
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• 1997

PVC 핏치를 산소분위기에서 안정화시킬 때 발생되는 화학반응 기구를 열중량 분석 및 FT-IR을 이용하여 규명하였다. PVC 핏치를 안정화시킬 \ulcorner 초기에 가속화현상이 이러나서 핏치내에 반응성이 강한 메칠기(-CH/ sub 3/)나 메칠렌기(-CH$_{2}$-)등이 산소와 반응하여 카보닐기(C=O)를 생성하면서 급격한 무게증가 현상이 발생하였다. 이때의 생성물들은 알데히드(aldehyde), 케톤(ketone), 알코올(alcohol)이며, 물 (H$_{2}$O)이 부산물로 발생된다. 이 가속화 현상에 의해 핏치내의 메칠기와 메칠렌기는 안정화 초기단계에서 대부분 산화되어 없어졌다. 안정화시간이 길어짐에 따라 생성된 알데히드나 일차 알코올의 산화가 발생하여 카르복실산(carboxylic acid)을 생성하고, 에테르 결합도 생성되었다. 이때에도 무게증가 현상이 발생하지만, 초기의 급격한 무게증가와는 달리 그 증가속도가 느리고, 시간이 경과함에 따라 증가속도는 더욱 느려졌다. 그리고, 안정화온도가 높고 안정화시간이 긴경우에는,카르복실산들의 탈수반응으로 인한 방향족 무수화물(aromatic anhydride)이 생성되었다. 29$0^{\circ}C$에서 24시간 안정화시킨 경우, 무게감소가 발생했는데, 이것은 카르복실산의 탈카르복실화(decarboxylation)반응에 의해 CO$_{2}$가 발생되었기 때문이다. 그리고, 안정화 온도가 높을수록 안정화에 무게증가의 최대값과 방향족 무수화물이 발생되는 무게증가 값이 작아지고, 안정화 초기단계에서 나타나는 가속화 현상의 구간도 짧아졌다.

• Proceedings of the Korean Society of Fisheries Technology Conference
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• 2003.05a
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• pp.365-366
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• 2003

주꾸미는 서해 연안 어족의 자원감소와 함께 어장 환경 악화에 의해 매년 생산량이 감소되고 있으며, 금후에는 양적 성장이 어려울 뿐만 아니라 어업인의 소득 감소가 예상되고 있다. 따라서 주꾸미의 생산량을 지속적이고 안정적으로 유지하기 위해서는 지금까지의 어선ㆍ어업에서 탈피하여 주꾸미의 인공 종묘생산 및 자원조성을 위한 종묘의 대량 방류가 필요하다. 주꾸미 종묘생산시 시료의 무게 측정, 표지작업, 인공채란, 수송 그리고 질병치료 등을 위해 주꾸미 유생을 그물망으로 포획하는 것은 유생에 물리적 손상과 스트레스를 주어 폐사의 1차 원인이 되기도 한다. (중략)

• The Korean Journal of Pesticide Science
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• v.2 no.3
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• pp.137-146
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• 1998

Laboratory tests were carried out to evaluate the effect of several insecticides with insect growth regulator (IGR) properties on the larval development of housefly, Musca domestica, which was collected at a large pigpen in Hamyang, Gyeongnam, Korea in 1997. Commercial formulations of the chemicals were diluted with tap water into a range of concentrations, and mixed with larval media. In addition to the IGRs, imidacloprid 5% WP was tested, too. The IGRs treated at the 2nd instar stage induced higher larval mortalities than percentages of malformed pupae. The result were, however, opposite when the IGRs were treated at the 3rd instar stage. Overall mortality resulting from larval death and malformed pupae was dependent on concentration. Diflubenzuron, teflubenzuron, triflumuron, flufenoxuron, tebufenozide, and imidacloprid, treated to the 2nd instar larvae, showed mortality over 95 % at concentrations of 5 ppm, 3 ppm, 30 ppm, 5 ppm, over 1000 ppm, 1000 ppm, respectively. Higher concentrations were needed to get the same level. of mortality in the 3rd instar larvae as that in the 2nd larvae. Overall mortality over 95% at the 3rd instar could be get at concentrations of 100 ppm, 10 ppm, 300 ppm, 10 ppm of diflubenzuron, teflubenzuron, triflumuron, flufenoxuron, respectively. Tebufenozide (1,000 ppm) and imidacloprid (300 ppm) were less effective than the other chemicals, showing only 36.7% and 86.7% mortalities, respectively. The chemicals also affected pupal weight at high concentrations. Decrease of pupal weight was distinct at high concentrations of teflubenzuron, flufenoxuron, tebufenozide, imidacloprid. Diflubenzuron and triflumuron were less effective. From these results it could be concluded that the IGR insecticides can be used as control agents by interfering with moulting and pupation process of housefly, by reducing pupal weight which could be resulted in low fertility and less oviposition.

• Journal of the Mineralogical Society of Korea
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• v.28 no.2
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• pp.135-145
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• 2015

In order to predict the deterioration of stone monument due to acid fog, an artificial fog test using pH4.0 and pH5.6 was applied to the Gyeongju Namsan granite, decite and marble. After the test had weathered Gyeongju Namsan granite a larger weight reduction due to acid fog than fresh one. Decite has shown the most significant changes among the tested rocks with about 0.005 % of weight reduction. Decite and weathered granite will have considerable weight reduction due to acid rain than the acid fog, whereas the marble was expected to show a weight reduction regardless of the phase of water. The porosity and water absorption rate of weathered granite had significantly increased. This result means that the weathered rock is predicted to be more susceptible to acid fog than the fresh rock. The absorption rate of the marble after the test had shown approximately 50 % increase. The color of the samples had slightly changed towards yellow, such tendency was greater shown in weathered rocks. The marble reacted with acid fog had an increased whiteness. A large amount of cation in the samples is caused mainly by the dissociation of minerals through the reaction with acid fog.

• Elastomers and Composites
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• v.48 no.4
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• pp.288-293
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• 2013

Crosslink characteristics of maleic anhydride-grafted EPDM (MAH-g-EPDM)/zinc oxide composite were investigated by weight losses after dichloroacetic acid (DCA)/toluene cosolvent extraction at different temperatures and by measurement of crosslink densities. The chemical changes were analyzed using attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR). The weight losses by extraction at high temperature ($90^{\circ}C$) were remarkably greater than those at room temperature and those by DCA/toluene cosolvent extraction were greater than those by toluene one by more than 5 times. The crosslink densities were measured after the solvent extraction, and the second crosslink densities were higher than the first ones. The first crosslink density was lower when the extraction temperature was high, and it was much lower for the toluene extraction than for the DCA/toluene cosolvent extraction. The second crosslink density of the sample extracted with DCA/toluene cosolvent was greater than that extracted with toluene. The extracted components were depending on the extraction solvents and temperatures, for example; only strong crosslinked networks were remained when extracting with DCA/toluene cosolvent at high temperature, while only uncrosslinked polymer chains were extracted when extracting with toluene at room temperature. Therefore, crosslink characteristics of the MAH-g-EPDM/zinc oxide composite can be analyzed by comparison of the extracted components according to the extraction solvents and temperatures and by measurement of successive crosslink densities.

• Korean Journal of Environmental Agriculture
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• v.28 no.1
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• pp.59-68
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• 2009

Single-dose toxicity test of germanium-fortified lettuce was investigated in mice. Both sexes of C57BL/6 mice were orally administered once at a dose of 2,000 mg/kg. No death, clinical signs and pathological findings related to the treatment were observed. In addition, no significant changes in feed consumption and body weight gain were obtained during the treatment period, in spite of day-to-day fluctuation of water consumption. There were no considerable changes in hematology and serum biochemistry, except a significant decrease in GPT, GOT and LDH. Several alterations were observed in organ weight and blood biochemistry, including thymus, ovaries, heart, kidney and platelet in male or female mice. The ability of spleen cells proliferation was almost same level as shown in control group. However the population of B cells, helper T cells and cytotoxic T cells was not comparably changed in all groups. Taken together, it is suggested that single oral dose of germanium-fortified lettuce to C57BU6 mice did not cause apparent toxicological change at the dose of 2,000 mg/kg body weight.

• Korean Journal of Poultry Science
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• v.42 no.4
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• pp.291-297
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• 2015

We investigated the effects of dietary pearlzyme (mudflat-bacteria origin protease) on growth performance and development of digestive organs in broilers. Two hundred forty, 4 day-old female Ross broiler chicks were divided into 2 groups (control vs. pearlzyme) which were randomly housed in 8 pens with 15 chicks/pen. They were fed one of two diets containing pearlzyme at 0 or 0.1% for 4 weeks. Dietary pearlzyme resulted in significant increase in body weight during the first week of the experiment (p<0.05). With age, weight gain and feed efficiency continued to decrease reaching significant level during the last week. Mortality was 3.3% in control but not in pearlzyme during the entire period of the experiment. Dietary pearlzyme resulted in increased weight (p<0.05) in the ceca and rectum, and increased length in the ceca (p<0.05). However, there were tendencies to increase the weight of the gizzard (p<0.071) but to decrease the length of the small intestine (p<0.068). The results of the current study show that dietary pearlzyme affects weight gain and the development of digestive organs.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.9 no.2
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• pp.93-98
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• 2011

Saline corrosion is one of the major degradation mechanisms for stainless steel type 304 (SS304) dry storage cask during the spent fuel interim storage period. Slow strain rate test (SSRT) and neutral salt spray test (NSS) were performed at $85^{\circ}C$ and $200^{\circ}C$ with 0.5 wt% sodium chloride mist sprayed on the cold-rolled SS304 specimens of different degrees of reduction in this study. The weight changes of the NSS specimens tested at $85^{\circ}C$ for 2000 hours differed greatly from those at $200^{\circ}C$. The weight loss of NSS specimens was not significant at $85^{\circ}C$ but the weight gain decreased gradually with increasing the cold-rolled reduction. The yield strength (YS) and ultimate tensile stress (UTS) values obtained from the SSRT tests for lightly cold-rolled specimens in the salt spray environment at $85^{\circ}C$ and $200^{\circ}C$ are slightly lower than in air. But for those with 20% reductions, the specimen strengths were no longer changed by the saline corrosion. The preliminary results demonstrated that the quality and performance of cold-rolled SS304 is acceptable for fabrication of dry storage casks. However, more work on the corrosion behavior of cold-rolled stainless steel in the saline atmosphere is needed to better understand its long-term performance.