• 한국표면공학회지
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• 제46권5호
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• pp.229-233
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• 2013

The small punch(SP) tests that can be applied to high strength sheet steel in automobile were carried out to evaluate the behavior of hydrogen embrittlement of DP sheet steels. In order to charge hydrogen at DP sheet steels, DP sheet steels were treated by the electrochemical hydrogen charging method under the charging conditions of current densities of 100, 150 and 200 $mA/cm^2$ for charging times of 5, 10, 25 and 50 hrs. Respectively, After hydrogen charging with experimental conditions, SP tests were performed. From the SP results, the correlations between the variation of bulb diameters and bulb heights with the hydrogen charging conditions were analysed. It was shown that the variation of bulb diameters were not significant with the hydrogen embrittlement due to the amounts of hydrogen charging. On the other hand, the bulb heights were observed to decrease with increasing hydrogen contents. It was thought that these results of the variation of bulb shapes after SP tests would be estimated as the index of evaluation of hydrogen embrittlement.

• 한국가스학회지
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• 제18권1호
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• pp.61-67
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• 2014

고강도 DP강의 수소취성 거동을 소형펀치시험을 통해 평가하였다. 이를 위해 첨가원소가 각기 다른 3종의 DP강 시험편에 전기화학적 방법으로 수소를 강제 주입시켰다. 수소주입 후, 수소주입량을 측정하였다. 수소주입량은 마르텐사이트 부피분율에 크게 의존하는 것으로 조사되었다. 전류밀도 150, $200mA/cm^2$ 조건에서 25시간이 포화상태에 도달하는 수소주입조건으로 나타났다. SP시험 후 SP에너지와 SP bulb 형상을 비교한 결과, 수소주입량의 증가에 따라 SP에너지와 SP bulb 높이가 감소하는 것으로 나타났다. 또한 SP bulb 파단면에서는 뚜렷한 facet와 층상형태의 벽개 파단면이 관찰되어 수소취성화를 관찰할 수 있었다.

• 한국균학회지
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• 제48권3호
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• pp.251-271
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• 2020

Diversity and community composition of bulb-associated fungi of Fritillaria Cirrhosae Bulbus source plants, which are used in traditional chinese medicine, in the eastern Himalaya-Hengduan Mountains, southwestern China, were estimated based on the internal transcribed spacer rDNA sequence analysis, using host plant species, geographic area, and plant phenology as variables. A total of 1,486 fungal sequences assigned to 251 operational taxonomical units (OTUs) were obtained from the bulbs. Fungal OTUs comprised 96.41% Ascomycotina, 3.52% Basidiomycotina, and 0.07% Zygomycotina. Sordariomycetes, Hypocreales, and Nectriaceae were the most frequent fungal lineages at each taxonomic rank. Fusarium, Ilyonectria, Tetracladium, Leptodontidium, and Tomentella were the top OTU-rich genera. Fusarium sp. 03, Ilyonectria rufa, Fusarium sp. 08, Ilyonectria sp. 03, and Leptodontidium orchidicola 03 represented the most frequent OTUs. Fusarium spp. were the most frequent general taxa. The distribution of fungal community exhibited preferences for host plant species, geographic area, and plant phenology. These findings are the foundation of our research on culturing and active metabolites of bulb-associated fungi of Fritillaria Cirrhosae Bulbus source plants.

• 한국가스학회지
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• 제18권5호
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• pp.40-46
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• 2014

전기화학적 방법으로 수소 주입시킨 5종의 고강도 DP강의 수소취성화 정도를 소형펀치시험으로 평가하였다. SP시험 후 SP흡수에너지는, $200mA/cm^2$ 전류밀도 조건의 DP5 시험편에서 수소주입시간이 5hr에서 50hr으로 증가함에 따라 363 kgf-mm에서 209 kgf-mm로 현저히 저하되는 것을 알 수 있었다. 전류밀도와 수소주입시간의 증가에 따라 수소주입량과 SP에너지 저하는 선형적인 상관관계를 갖는 것으로 조사되었다. 또한 SP시험에 의해 생성된 bulb의 높이 변화는 1.79 mm에서 1.59 mm로 낮아지는 것으로 조사되었다. 이는 앞서의 SP 흡수에너지 결과와 유사한 경향으로 나타나, 수소취성평가의 지표로 활용 가능할 것으로 사료된다. 균열 파단부위의 SEM 관찰에서 수소주입량 증가에 따라 파단면은 취성파면 형태로 진행되는 것을 확인할 수 있었다.

• 한국환경복원기술학회지
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• 제13권6호
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• pp.39-48
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• 2010

The purpose of this study was to analyze air temperature decreasing effects by shading and ventilation at micro-scale experiment plots, especially focused on the Wet Bulb Globe Temperature (WBGT) in outdoor spaces. To monitor the time-serial changes of Dry-bulb Temperature (DT), Globe Temperature (GT) and Relative Humidity (RH) in the wind blocking and shading conditions, Two hexahedral steel frames were established on the open grass field, the dimension of each frame was 1.5m(W)${\times}$1.5m(L)${\times}$1.5m(H). Four vertical side of one frame was covered by transparent polyethylene film to prevent wind passing through (Wind break plot; WP). The top side of the other frame was covered with shading curtain which intercept 95% of solar light and energy (Shading plot; SP). And, Another vertical steel frame without any treatment preventing ventilation and sunlight was set up, which represents natural conditions (Control plot; CP). The major findings were as follows; 1. The average globe temperature (GT) was highest at WP showing $50.94^{\circ}C$ and lowest at SP showing $34.58^{\circ}C$. The GT of natural condition (SP) was $42.31^{\circ}C$ locating the midst between WP and SP. The difference of GT of each plot was about $8-16^{\circ}C$, which means the ventilation and shading has significant effect on decreasing the temperature. 2. WP showed the highest average dry-bulb temperature (DT) of $38.41^{\circ}C$ which apparently differ from SP and CP showing $31.94^{\circ}C$ and $33.15^{\circ}C$ respectively. The DT of SP and CP were nearly the same. 3. The average relative humidity (RH) was lowest at WP showing 15.21%, but SP and CP had similar RH 28.79%, 28.02% respectively. 4. The average of calculated WBGT were the highest at the WP ($27.61^{\circ}C$) and the lowest at the SP ($23.64^{\circ}C$). The CP ($25.49^{\circ}C$) was in the middle of the others. As summery, compared with natural condition (CP), the wind blocking increased about $2.11^{\circ}C$ WBGT, but the shading decreased about $1.84^{\circ}C$ WBGT. So It can be apparently said that the open space with much shading trees, sheltering furnitures and well-delivered wind corridor can reduce useless and even harmful energy for human outdoor activity considerably in outdoor spaces.

• 원예과학기술지
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• 제29권6호
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• pp.575-582
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• 2011

본 실험은 접목선인장의 품질변화을 조사하고, 선박운송 중 발생되는 부패균에 대하여 조사하고자 실시하였다. 식물재료로 비모란의 '후광', '후홍', '연화', '황월'의 네 품종을, 산취의 '골드크라운', '옐로우크라운'를 사용하였으며, 모의 운송기간 중 생체중, 구경, $CO_2$ 발생량, 부패율을 측정하였다. 모의운송 40일 후에는 접목선인장을 온실 환경(평균온도 $28{\pm}12^{\circ}C$, 평균습도 $36{\pm}15.3%$)하에 두고 28일간 재생률과 부패율을 조사하였다. 모든 품종에서 시간이 지남에 따라 생체중과 구경이 감소되는 것으로 나타났으며, $CO_2$ 발생량은 품종간 유의한 차이를 보이지 않았다. 접수 부분이 삼각주 부분 보다 부패율이 높은 것으로 조사되었으며, 부패에 따른 부패균을 분석한 결과, 비모란에서는 Alternaria sp., Cladosporium sp., Colletotrichum sp., Fusarium sp., Penicillium sp. 등이 조사되었으며, 산취에서도 Alternaria sp., Bipolaris sp., Cladospoirum sp. 등이 조사되었다. 따라서 접목선인장의 품질을 유지 및 향상시키기 위해서는 수확 후 부터 수출까지 부패발생 요인을 분석하고, 부패율을 최소화시키기 위한 처리기술 개발이 필요하다고 판단된다.

• Mycobiology
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• 제35권4호
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• pp.235-237
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• 2007

Leaf blight and bulb rot symptoms were observed on narcissus plants grown in Yongin, Cheongwon and Namhae areas in Korea during disease survey from 1999 to 2002. A total of 15 isolates of Botrytis sp. were obtained from the infected plant parts of narcissus. All the isolates were identified as Botrytis narcissicola based on their morphological and cultural characteristics. Three isolates of B. narcissicola were tested for their pathogenicity to leaves and bulbs of narcissus by artificial inoculation. All the isolates induced leaf blight and bulb rot symptoms on the plants of narcissus by artificial inoculation. The symptoms induced by artificial inoculation were similar to those observed in the fields. This is the first report of narcissus smoulder caused by B. narcissicola in Korea.

• 식물병연구
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• 제29권2호
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• pp.184-187
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• 2023

In May 2020, we surveyed disease occurrence on vegetables grown in Seosan area, Korea. During the disease survey, white rot symptoms were observed in Korean wild chive (Allium monanthum) plants growing in fields. The symptoms occurred mainly in the seed bulb-producing fields of the crop. The above ground parts of the diseased plants displayed premature yellowing and dying of older leaves and stunting of the plants. The bulbs and roots of the diseased plants turned black and rotted. The disease occurred in a range of 1-60% in four of the eight fields surveyed. Three isolates of Sclerotium sp. were obtained from the bulb lesions of diseased plants. All isolates were identified as Stromatinia cepivora based on the morphological characteristics and phylogenetic analysis. Pathogenicity of the isolates on Korean wild chive was confirmed by artificial inoculation test. The lesions induced by the inoculation test were similar to those observed in the investigated fields. This is the first report of S. cepivora causing white rot in Korean wild chive.

• Journal of Species Research
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• 제10권1호
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• pp.86-98
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• 2021

The genus Pholcus Walckenaer, 1805 is the largest genus among the cellar spider family Pholcidae C.L. Koch, 1850, including 339 species. To date, 33 species in the genus are known to be distributed in Korea, being placed into three species-groups(crypticolens-group, phalangioides-group, and phungiformes-group). About 91% of these species are endemic to Korea. In this study, four new species of the genus Pholcus were discovered in Korea, viz, Pholcus chuncheonensis Lee, Choi and Kim sp. nov., Pholcus pajuensis Lee, Choi and Kim sp. nov., Pholcus pocheonensis Lee, Choi and Kim sp. nov., and Pholcus unaksanensis Lee, Choi and Kim sp. nov. These new species are classified as members of the phungiformes-group, having morphological characteristics such as male chelicerae with a frontal apophysis, palpal tibia with a prolateroventral tubercle, and genital bulb without appendix or having pseudo-appendix, but can be distinguished from congeners by characteristics of the male palp and female genitalia. Detailed descriptions and a key to new species are provided with accompanying photographs.

• 원예과학기술지
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• 제33권6호
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• pp.883-890
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• 2015

토양 전염균인 Fusarium oxysporum f. sp. lilii(Fol)은 식물에 심각한 위협을 주는 균으로 특히 백합의 구근과 꽃에 심각한 영향을 준다. 따라서 저항성 품종의 육성이 중요시되고 있는데, 저항성 품종이 육성되기 위해서는 신속, 간편한 검정법 체계와 유전적 다양성이 요구되는 상황이다. 본 실험에서는 기내배양시스템을 이용하여 백합의 Fol에 대한 저항성 정도를 효율적으로 검정하는 방법을 확립하고자 하였다. 병원균의 배양조건, 병원균의 식물체 접종 농도, 대상 절편체 종류, 접종 후 적정 발병 기간 등과 같은 조건을 단독, 혹은 조합하여 실험 한 결과 다음의 기내검정조건을 확립하였다. Fol균을 6일 동안 PDA 배지에서 배양한 후 포자 현탁액을 $1.0{\times}10^4$ $spores{\cdot}mL^{-1}$농도로 조절하여 기내배양 중인 식물체의 잎을 $1.5{\times}2.0cm^2$의 크기로 절단하여 $25^{\circ}C$, 암조건에서 22시간 침지시켜 접종하였다. 접종이 끝난 잎절편체는 0.6% 한천배지에 치상하여 온도 $25^{\circ}C$, 습도 50%, 16시간 광조건(광도 $40{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$)을 유지하면서 병의 발달을 관찰하였다. 발병 정도를 지수화하여 통계처리를 하였다. 기내검정을 통하여 저항성 및 민감성으로 선발한 백합종들을 토양검정법으로 실험한 결과 동일한 저항성 정도를 얻을 수 있었으며, 이는 본 연구에서 확립한 Fol에 대한 구근부패병 기내검정법이 효율적으로 품종 선발에 이용될 수 있음을 보여준다고 하겠다.