• 열처리공학회지
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• 제24권4호
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• pp.209-216
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• 2011

Surface coatings were prepared on SKD11 core mold steel by plasma electrolytic oxidation (PEO). The coatings were investigated about the formation condition of core mold steel. SKD11 were coated by PEO in a mix solution of Sodium Aluminate $NaAlO_2$ (10 g/l), Sodium Silicate powder $Na_2SiO_3$ (0.5 g/l), Sodium tungstate dihydrate $Na_2WO_42H_2O$ (0.5 g/l) at less than $30^{\circ}C$. The electrical condition were voltage : 500~600 V; Pulse : 600~1800 Hz; current density 15~20 $A/dm^2$ various time : 3 min~40 min. The coatings surface morphology, cross-section, friction coefficient, hardness were investigated. The PEO coatings on SKD11 core mold steel showed the extended service life.

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2002년도 총회 및 추계학술발표회
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• pp.49.1-49
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• 2002

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2002년도 총회 및 추계학술발표회
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• pp.48-49
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• 2002

• 한국식물병리학회:학술대회논문집
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• 한국식물병리학회 2003년도 정기총회 및 추계학술발표회
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• pp.90.2-91
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• 2003

In commercial greenhouses, senescent flower petals or flowers of vegetables such as tomato, strawberry, hot pepper and zucchini squash were blighted to be removed from fruits within five days after spraying of Trichoderma harzianum YC459 (TORY), a biocontrol agent for the gray mold rot of vegetables caused by B. cinerea The mechanism for selective colonization of senescent floral tissues by T. harzianum YC459 was elucidated using fresh and senescent (Hays and 14days after flowering, respectively) floral tissues of zucchini squash (Cucurbita moschata Duchesne). The spores of T. hrzianum YC459 were produced more on agar and liquid culture media supplemented with 5％ dry powder of senescent floral tissues than fresh tissues during 15days. Mycelial growth was also much better in the media with senescent tissues than with fresh tissues. Enzyme activities of amylase, polygalacturonase and cellulase in the liquid media which might be involved in the colonization of tissues by T. harzianum YC459 were compared. The activities of three enzymes were much higher in the media with senescent floral tissues than with fresh floral tissues reaching to the maximum during 9 to 12days of incubation. Based on the results, the removal of senescent floral tissues, a possible inoculum source of the pathogen, may be another mechanism for biocontrol of gray mold rot of vegetables by T. harzianum YC459.

• 한국표면공학회지
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• 제54권5호
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• pp.285-293
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• 2021

High-entropy TiAlCrSiN nano-composite coating was designed to improve mold life for high temperature liquid molding. Alloy design, powder fabrication and single alloying target fabrication for the high-entropy nano-composite coating were carried out. Using the single alloying target, an arc ion plating method was applied to prepare a TiAlCrSiN nano-composite coating had a 30 nm TiAlCrSiN layers are deposited layer by layer, and form about 4 ㎛-thickness of multi-layered coating. TiAlCrSiN nano-composite coating had a high hardness of about 39.9 GPa and a low coefficient of friction of less than about 0.47 in a dry environment. In addition, there was no change in the structure of the coating after the dissolution loss test in the molten metal at a temperature of about 1100 degrees.

• Journal of Dairy Science and Biotechnology
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• 제35권3호
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• pp.152-161
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• 2017

Cheese is an excellent substrate for yeast and mold growth. These organisms can cause cheese spoilage, resulting in significant food wastage and economic losses. In the context of cheese spoilage, the presence and effects of spoilage or pathogenic bacteria are well documented. In contrast, although yeasts and molds are responsible for much dairy food wastage, only a few studies have examined the diversity of spoilage fungi. This article reviews the spoilage yeasts and molds affecting cheeses in various countries. The diversity and number of fungi present were found to depend on the type of cheese. Important fungi growing on cheese include Candida spp., Galactomyces spp., Debaryomyces spp., Yarrowia spp., Penicillium spp., Aspergillus spp., Cladosporium spp., Geotrichum spp., Mucor spp., and Trichoderma spp.. In addition, several mold spoilage species, such as Aspergillus spp. and Penicillium spp., are able to produce mycotoxins, which may also be toxic to humans. There are many ways to eliminate or reduce toxin levels in foods and feeds. However, the best way to avoid mycotoxins in cheese is to prevent mold contamination since there are limitations to mold degradation or detoxifications in cheese. Chemical preservatives, natural products, and modified atmosphere packaging have been used to prevent or delay mold spoilage and improve product shelf life and food safety.

• 생명과학회지
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• 제19권2호
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• pp.241-248
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• 2009

본 시험은 혐기성 박테리아, 효모 및 곰팡이로 제조한 synbiotics를 TMR에 첨가하여 7일 동안 발효시킨 후, 성분함량의 변화 및 개봉하여 공기에 노출시킨 기간에 따른 발효특성의 변화를 알아보기 위하여 수행되었다. 처리구는 무처리구인 US구, 혐기성 박테리아와 prebiotics로 구성된 BS구, 혐기성 효모와 prebiotics로 구성된 YS, 혐기성 곰팡이와 prebiotics로 구성된 MS구, 혐기성 박테리아와 혐기성 곰팡이 및 prebiotics를 조합한 BMS구, 혐기성 효모와 혐기성 곰팡이 그리고 prebiotics를 조합한 YMS구, 혐기성 박테리아와 혐기성 효모 그리고 prebiotics를 조합한 BYS구, 혐기성 박테리아, 효모 및 곰팡이 복합물과 prebiotics를 조합한 BMYS구로서 총 8 처리구로 나누었다. 개봉 후 노출기간(1, 3, 5, 7, 14, 및 21일)별 3반복으로 총 144개의 bag을 공시사료로 제조하였다. 혐기 발효 TMR의 개봉 후 성분함량과 공기노출에 따른 발효특성에 대한 결과를 요약하면 다음과 같다. 혐기 발효시킨 TMR의 수분함량은 약 41${\sim}$45% 범위로서원 사료와 비슷한 수준이었다. 조단백질 함량은 기초 사료에 비해 무처리 대조구에서는 11.7${\sim}$14.8% 줄어들었으나, BMYS 처리구에서는 약 11%가 증가되었다. BMYS 처리구에서는 조섬유 함량이 기초사료에 비해 약 32% 감소되었고, NDF 및 ADF도 각각 15.5% 및 26.1%가 감소되었다. 공시사료의 내부 온도는 개봉 7일째에 전 처리구에서 높게 나타났다. 발효 TMR의 pH는 개봉 5일까지는 처리 간에 차이가 없었으나, 개봉 7일 이후부터는 높아졌고, BMS구에서 개봉 14일째에 가장 높았다(P<0.05). 산에 대한 완충능력은 개봉 후, 시간이 경과함에 따라 산의 첨가량이 많아져 완충능력이 높아지는 경향으로서 대체로 개봉 7일 이후부터 시작하여 14일째에 peak를 이루었다. 발효 TMR 즙액의 $NH_3-N$ 농도는 개봉 후 5일째에 peak를 이루었으며, 휘발성지방산 함량은 매우 낮은 수준이었다. 이상의 결과로 볼 때, BMYS 처리구에서 단백질 함량은 높아지고, 섬유소함량은 낮아졌지만, 공기 중 노출기간별 발효특성에서는 혐기성 synbiotics의 첨가에 따른 영향은 없는 것으로 나타났다.

• The Plant Pathology Journal
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• 제33권3호
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• pp.337-344
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• 2017

To develop a commercial product using the mycoparasitic fungus Simplicillium lamellicola BCP, the scale-up of conidia production from a 5-l jar to a 5,000-l pilot bioreactor, optimization of the freeze-drying of the fermentation broth, and preparation of a wettable powder-type formulation were performed. Then, its disease control efficacy was evaluated against gray mold diseases of tomato and ginseng plants in field conditions. The final conidial yields of S. lamellicola BCP were $3.3{\times}10^9conidia/ml$ for a 5-l jar, $3.5{\times}10^9conidia/ml$ for a 500-l pilot vessel, and $3.1{\times}10^9conidia/ml$ for a 5,000-l pilot bioreactor. The conidial yield in the 5,000-l pilot bioreactor was comparable to that in the 5-l jar and 500-l pilot vessel. On the other hand, the highest conidial viability of 86% was obtained by the freeze-drying method using an additive combination of lactose, trehalose, soybean meal, and glycerin. Using the freeze-dried sample, a wettable powder-type formulation (active ingredient 10%; BCP-WP10) was prepared. A conidial viability of more than 50% was maintained in BCP-WP10 until 22 weeks for storage at $40^{\circ}C$. BCP-WP10 effectively suppressed the development of gray mold disease on tomato with control efficacies of 64.7% and 82.6% at 500- and 250-fold dilutions, respectively. It also reduced the incidence of gray mold on ginseng by 65.6% and 81.3% at 500- and 250-fold dilutions, respectively. The results indicated that the new microbial fungicide BCP-WP10 can be used widely to control gray mold diseases of various crops including tomato and ginseng.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.254-259
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• 2004

The research on surface modification technology has been advanced to change the properties of engineering material. Ion implantation is a novel surface modification technology to enhance the mechanical, chemical and electronic properties of mechanical parts. In this research, nitrogen ions are implanted into aluminum for mold to improve endurance and life span. To analyze modification of surface properties, micro hardness, friction coefficient, wear resistance, contact angle, and surface roughness were measured. Hardness of ion implanted specimens was higher than untreated specimen and friction coefficient was also improved. In this experiment, it can be expected that nitrogen ion implantation can contribute to enhance the mechanical properties of material and ion implantation technology may also be applied to other materials.

• 한국생산제조학회지
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• 제26권4호
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• pp.357-364
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• 2017

Metal casting is a process in which molten metal or liquid metal is poured into a mold made of sand, metal, or ceramic. The mold contains a cavity of the desired shape to form geometrically complex parts. The casting process is used to create complex shapes that are difficult to make using conventional manufacturing practices. For the optimal casting process design of sleeve parts, various analyses were performed in this study using commercial finite element analysis software. The simulation was focused on the behaviors of molten metal during the mold filling and solidification stages for the precision and sand casting products. This study developed high-life sleeve parts for the sink roll of continuous hot-dip galvanizing equipment by applying a wear-resistant alloy casting process.