• 문화기술의 융합
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• 제8권6호
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• pp.943-951
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• 2022

본 연구에서는 사과, 배, 무 등 8종 과채류를 절단하고 열수추출물과 과채류 증숙열수추출물을 제조하고 실험기질로 사용하였다. 실험기질에 홍삼추출물 1%(W/V)와 유산균발효 추출물에 유산균 8종 혼합스타터를 첨가하여 발효한 결과, ginsenosides의 패턴과 함량은 과채류 추출물군과 증숙 처리군에서는 거의 변화가 없었다. 그러나 유산균 발효군에서는 발효과정과 처리에 따라 TLC 패턴이 변하여 Rg₃(S) 및 Rg₅으로 전환되는 진세노사이드 함량이 증가하였다. 4종의 과채류추출물 모두에서 유산균 수(cfu)의 변화는 관찰되지 않았다. 유산균 CFU의 수는 과채류 추출물의 4가지 발효군에서 약간 감소하였으나 유익균의 생장 억제 효과는 유의하게 나타나지 않았다. 3가지 유해균의 증식억제 효과는 4가지 과채추출물에서 대장균과 슈도모나스의 증식에 영향을 받지 않았다. 그러나 살모넬라균의 증식은 억제되었으며, 이는 과채류 증숙 열수추출물 및 홍삼추출물 첨가 여부에 관계없이 과채류 추출물의 생장억제효과로 확인되었다.

• 펄프종이기술
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• 제45권2호
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• pp.56-65
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• 2013

Electron beam treatment was applied for improving dissolution of cellulose with ionic liquids. Two ionic liquids, 1-allyl-3-methylimidazolium chloride ([Amim]Cl]: AC) and 1,3-dimethylimidazolium methylphosphite ([Dmim][$(MeO)(H)PO_2$]: Me) were used for this experiment. Treatment with electron beams up to dose of 400 kGy resulted in the increase of hot water extract and alkali extract of cotton pulp and the great reduction in the molecular weight of cellulose. For the dissolution of cotton pulp with two ionic liquids, the electron beam treated samples showed faster dissolution. The dissolved cellulose with Me ionic liquid were regenerated with acetonitrile and the structure of regenerated cellulose showed distinct difference depending on the electron beam treatment. Those results provide the electron beam pre-treatment could be applied as an energy efficient and environmentally benign method to increase the dissolution of cellulose with ionic liquids.

• Journal of the Korean Wood Science and Technology
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• 제15권3호
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• pp.56-67
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• 1987

Plywoods used for construction as a decorative interior material are inflammable and can make fire accidents, causing destruction of human life and property. Therefore, it is indeed required to make fire-retardant treated plywood. In this study, 3.7mm yellow meranti plywoods were soaked in 18% boric acid solutions and tap water by hot-cold bath for 1/2, 2/2, 4/2, 6/2 hours and redrying of treated plywoods was carried out by press drying at the platen temperature of 110, 130, 160, $180^{\circ}C$ and then it was conducted to investigate solution absorption, drying rates, dynamic young's modulus. specific gravity and fire-retardant factors such as burning point, flame spread length. flame exhausted time, back side carbonized area and weight loss by treating time, treating solutions and platen temperature. The results are as follows; 1. When plywood was impregnated with the hot bath temperature of $70^{\circ}C$ for 1. 2, 4, 6 hours and the cold bath temperature of $15^{\circ}C$ for 2 hours respectively, retentions of boric acid were 1.565, l.597, 1.643, 1.709kg/$(30cm)^3$ and all of them exceeded the minimum retention [1.125kg/$(30cm)^3$] even in the shortest treatment. 2. In hot-cold bath method for 1/2 hours, the drying rates of treated plywood remarkably increased with the extension of platen temperature of 110, 130, 160, $180^{\circ}C$ and the values of boric acid treated plywood were 5.900, 10.196, 45.42, 54.958m.c%/min and the values of water treated plywood were 6.014, 12.373, 46.520, 55.730m.c%/min and drying rates of water treated plywood were faster than those of boric acid treated plywood. 3. The values of boric acid treated plywoods in dynamic young's modulus were widely higher than those of water treated plywoods. And it can be observed that there were highly significant differences for treating time between dynamic young's modulus, and the values of boric acid plywoods increased with the extension of treating time but on the contrary water treated plywoods were decreased values with prolonged time 4. It was observed that there were highly significant differences for platen temperature between dynamic young's modulus. When the values of water treated plywoods in dyna nic young's modulus were abruptly decreased according to the rise of platen temperature. boric acid treated plywoods showed rather increased values at $160^{\circ}C$ of platen temperature. And in 2- way interactions, there were also highly significant for dynamic young's modulus between treating time x treating solutions and platen temperature x treating solutions. 5. Correlation coefficients of fire-retardant factors were shown in table 5. It could be recognized that there were close correlations between the treating solutions and burning point, flame spread length, back side carbonized area, flame exhausted time and weight loss, but there was no correlation between fire-retardant factors and treating time and platen temperature. 6. From table 6, it can be observed that there were highly significant differences for burning point, flame spread length, flame exhausted time, back side carbonized area, weight loss between treating solutions. And in 2-way interactions, there were highly significant for burning point, flame spread length, weight loss between treating time $\times$ treating solutions.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회B
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• pp.2315-2320
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• 2007

This paper presents an investigative study on the efficacy of a new physical water treatment (PWT) technology using an oscillating electric field to mitigate mineral fouling in heat exchangers. Parallel graphite electrode plates immersed in water were used to generate the electric field directly in water. Artificial hard water at 500 ppm hardness was used in all fouling tests. The inlet temperatures were maintained at 23.5${\pm}$0.5$^{\circ}C$ and 85${\pm}$0.5$^{\circ}C$ for cold and hot water sides, respectively. The results at a cold water-side velocity of 0.3 m/s showed a 16-60% drop in fouling resistances from the baseline test depending on the frequency of the electric field for the PWT-treated cases.

• 동력기계공학회지
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• 제15권5호
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• pp.22-29
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• 2011

In this study, the damage mechanism of large scale steam turbine due to water induction was analyzed and recovery characteristics were reviewed. A turbine consists of the rotating rotor and the stationary casing, and the clearance between them is very small for the efficiency enhancement. If water induction, while relatively cold steam or water is introduced into turbine, occurs, the considerable humping is caused at the casing near the initial water induction point and that induces the rubbing between rotor and casing. Finally, it leads to the catastrophic failure. Bowed rotor has the different characteristics in the recovery depending on damage degree. The elastic deformation due to light rubbing is recovered by turning the rotor with 3 rpm under normal operation condition, but most plastic deformation due to rubbing deforms the local microstructure and that results in permanent deformation which could not be recovered under normal operation condition. Bowed rotor has diverse characteristics depending on the recovery method, and the method is empirical and needs the cutting edge technology. Careful recovery treatment of the rotor will eliminate the risks and secure the high quality rotor similar to new rotor. If any critical error is made during the recovery, the rotor would not be recovered permanently and it should be scrapped.

• 한국물환경학회지
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• 제36권2호
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• pp.153-163
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• 2020

Magnetic separation technology is an efficient and environmentally friendly technology. Compared with the traditional wastewater treatment technology, the magnetic separation technology has its unique advantages and characteristics, and has been widely applied in the field of wastewater treatment. In particular, the emergence of superconducting magnetic separation technology makes possible for high application potential and value. In this paper, which through consulting with the literatures of Korea, Chinese, United States and other countries, the magnetic separation technology applied to wastewater treatment was mainly divided into direct application of magnetic field, flocculation, adsorption, catalysis and separation coupling technology. Advantages and limitations of the magnetic separation technology in sewage treatment and its future development were also studied. Currently, magnetic separation technology needs to be studied for additional improvement in processing mechanism, design optimization of magnetic carrier and magnetic separator, and overcoming engineering application lag. The selection, optimization and manufacturing of cheap magnetic beads, highly adsorbed and easily desorbed magnetic beads, specific magnetic beads, nanocomposite magnetic beads and the research of magnetic beads recovery technology will be hot application of the magnetic separation technology based on the magnetic carriers in wastewater treatment. In order to further reduce the investment and operation costs and to promote the application of engineering, it is necessary to strengthen the research and development of high field strength using inexpensive and energy-saving magnet materials, specifically through design and development of new high efficiency magnetic separators/filters, magnetic separators and superconducting magnetic separators.

• The Plant Pathology Journal
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• 제23권3호
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• pp.174-179
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• 2007

Seedlot disinfection techniques to control mung bean sprout rot caused by Colletoricum acutatum and C. gloeosporioides were evaluated for commercial production scheme. Soaking seedlots in propolis (100 X) and ethanol (20% for 30 min) appeared promising with control values of 85.5 and 80.8 respectively, but still resulted in up to 20% rot incidence. None of the C. acutatum conidia survived through hot water immersion treatment (HWT) for 10 min at temperatures of 55, 60 and $65^{\circ}C$, whereas the effective range of the dry heat treatment (DHT) was $60-65^{\circ}C$. Tolerance of mung bean seedlot, as estimated by hypocotyl elongation and root growth, was lower for HWT than for DHT. Germination and growth of sprouts were excellent over the range of $55-65^{\circ}C\;at\;5^{\circ}C$ intervals, except for HWT at $65^{\circ}C$ for 5 min. At this marginal condition, heat damage appeared so that approximately 2% of seeds failed to sprout to normal germling and retarded sprouts were less than 5% with coarse wrinkled hypocotyls. These results suggested that DHT would be more feasible to disinfect mung bean seedlots for commercial sprout production. Heat treatment at above ranges was highly effective in eliminating the epiphytic bacterial strains associated with marketed sprout rot samples. HWT of seedlot at 55 and $60^{\circ}C$ for 5 min resulted in successful control of mung bean sprout rot incidence with marketable sprout quality. DHT at 60 and $65^{\circ}C$ for 30 min also gave good results through the small-scale sprouting system. Therefore, we optimized DHT scheme at 60 and $65^{\circ}C$ for 30 min, considering the practical value of seedlot disinfection with high precision and accuracy. This was further proved to be a feasible and reliable method against anthracnose incidence and those bacterial strains associated with marketed sprout rot samples as well, through factory scale mung bean sprout production system.

• 한국식품저장유통학회지
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• 제23권1호
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• pp.27-33
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• 2016

본 연구에서는 신선편이 '로메인' 상추의 신선편이 가공 시 열수처리(45, 50, $55^{\circ}C/2min$)가 저장 중의 품질특성에 미치는 영향에 대하여 조사하였다. 각 처리구는 $5^{\circ}C$에서 5일간 저장한 후 관능품질, 호흡률, 에틸렌 발생량, 총균수, 갈변도, 총페놀, 비타민 C, 항산화 활성(DPPH, ABTS, FRAP)을 분석하였다. 본 연구에서 실시한 모든 열처리 조건은 총페놀 함량의 변화에 미치는 영향은 없었다. $45^{\circ}C$ 처리시에는 호흡과 에틸렌 발생이 증가하고 비타민 C 함량과 항산화 활성이 감소되었으며 갈변 억제 효과도 미미하였다. $55^{\circ}C$ 조건에서는 조직의 연화가 발생되는 문제가 발생하였다. $50^{\circ}C$ 열처리를 2분간 실시할 경우 조직감, 색, 미생물증식, 갈변도에서 가장 우수한 품질 상태를 나타내었으며, 저장 후 비타민 C 함량과 항산화 활성이 높게 유지되었다. 따라서 본 연구 결과 $50^{\circ}C$ 열처리 조건은 신선편이 '로메인' 상추의 저장 중 품질 및 항산화 활성을 유지시킬 수 있는 기술로 활용될 수 있을 것으로 판단되었다.

• 대한한의학원전학회지
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• 제32권2호
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• pp.71-92
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• 2019

Objectives : To examine various ways non-glutinous rice has been applied in different formulas of "Shanghanlun" and the relationship between non-glutinous rice and the formulas' effects. Methods : First, texts that included non-glutinous rice were selected from the "Shanghanlun". Then, they were categorized according to the application of non-glutinous rice, followed by analysis of its relationship with each formula. Results : Most formulas that used non-glutinous rice in raw form when decocting with other ingredients included Shigao. Non-glutinous rice alleviates coldness of Shigao as in the case with Taohuatang where it stops diarrhea. Non-glutinous rice used in Wumeiwan warms the center and boosts Qi and helps the medicinal ingredients to bind when made into pellets. In Guizhitang and Lizhongwan, non-glutinous rice assists Stomach Qi. In Shizaotang, porridge is taken after diarrhea to help quick recovery. To prevent damage of Zheng Qi, Baisan can be mixed with rice water for administration. The level of cathartic effect can be managed through giving cold or hot porridge to the patient according to his/her response to the medicine. Mazirenwan, Mulizexiesan, Banxiasan, Sinisan, Wulingsan are mixed in rice water for administration. It makes it easier to swallow than when mixed with plain water. The application of rice flour is either internal or external. In Zhufutang, where rice flour is parched, it harmonizes the center and stops diarrhea. In Daqinglongtang when there is too much perspiration, warm powder is sprinkled on the skin to stop sweating. Clear porridge in Jiuziyisifang and rice flour in Shechuangzisan were exclusive to "Jinguiyaolue", while Baisan and rice water mixture could only be found in "Shanghanlun". Conclusions : The excavation and research on various ways non-glutinous rice was applied in treatment holds certain meaning in contemporary practice of Korean Medicine where treatment leans heavily on medicinal treatment rather than food, and all ingredients are boiled together in large quantities for most decoctions.

• 한국식품저장유통학회지
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• 제18권1호
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• pp.124-129
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• 2011

PC12 신경세포를 이용하여 구아바 열매와 잎 추출물이 $H_2O_2$로 유도된 신경세포 독성에 대한 보호 효과를 조사하였다. 구아바 열매와 잎 열수 추출물의 총페놀성 화합물 함량은 각각 11.75 및 293.25 mg/g이었고, gallic acid 함량은 각각 22.78 및 117.34 mg/100 g이었다. $H_2O_2$ 처리한 PC12 cell내의 활성산소 생성억제효과를 측정한 결과 구아바 잎열수 추출물에서 높은 활성산소 생성 억제효과를 보였다. MTT방법을 이용하여 $H_2O_2$로 유도된 PC12 신경세포에 대한 보호효과를 측정한 결과 구아바 열매와 잎 열수 추출물은 높은 신경세포 보호효과를 보였고, LDH release 실험결과 모든 농도에서 세포막 보호효과를 나타내었다. 본 연구 결과를 종합해 볼 때, 구아바 열매와 잎 열수 추출물의 항산화활성과 산화적 스트레스로부터의 신경세포 보호효과를 나타내어 퇴행성 뇌신경질환 등의 예방 및 개선을 위한 산업화 소재로서의 활용 가능성이 높다고 판단된다.