• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.330-330
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• 2007

Polycrystalline mercuric iodide $HgI_2$) films are being developed as a new detector technology for digital x-ray imaging. The $HgI_2$ is generally vacuum deposited by physical vapor deposition (PVD) process. But the PVD thick deposition has been caused any instability in the biasing due to any defects or cracks. In this work we present a new particle-in-binder (PIB) methodologies used for the $HgI_2$ thick films. These growth techniques can be easily extended to produce much larger film areas. This paper, for the first time, presents results and comparison of polycrystalline $HgI_2$ films derived by various PIB methods. We investigated the structural and morphological properties of the films using X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis. The films were characterized with respect to their electrical properties and in response to x-ray photons. Physical and electrical results were also compared between conventional polycrystalline PVD and our detectors. Leakage current as low as $350\;pA/cm^2$ at the bias voltage of ~ 200 V has been observed. And high sensitivity and good linearity in the response to x-rays was obtained in the film derived by PIB sedimentation method. Our future efforts will concentrate on optimization of film growth techniques for uniform large area deposition on image readout arrays.

• 한국균학회지
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• 제42권4호
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• pp.353-356
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• 2014

2013년 8월, 경기도 화성시에 위치한 과수원에서 체리 과실에 회색의 포자 덩어리가 발생하는 잿빛무늬병 증상이 관찰되었다. 과실에 갈색의 수침상 원형 병반이 나타나고, 진전되면 과실 전체가 부패하였다. 부패된 과실에 회갈색 내지 연회색의 포자덩어리가 관찰되었다. 병든 체리 과실에서 2개의 Monilinia균을 분리하여 균학적 특성을 조사한 결과 M. fructicola로 동정되었다. 이러한 결과를 확인하기 위하여 ITS 영역의 염기서열을 분석하였다. 그 결과, 분리균은 모두 M. fructicola로 확인되었다. 체리 과실을 상처구와 무상처구로 구분하고, 포자현탁액을 접종하여 병원성을 확인한 결과, 접종 7일 후 상처의 유무에 관계없이 분리균을 접종한 부위에서 수침상의 둥근 병반이 관찰되었다. 따라서 본 병을 Monilinia fructicola에 의한 체리잿빛무늬병으로 명명하며, 이 균에 의한 잿빛무늬병의 발생을 국내 최초로 보고한다.

• 한국균학회지
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• 제45권1호
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• pp.23-30
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• 2017

각종 나뭇잎들의 효모 분포특성을 알아보기 위하여 대전광역시 서부지역에 위치한 옥녀봉과 연자산의 나뭇잎들로부터 야생효모들을 분리, 동정하였고 이들로부터 국내 미기록 효모들을 선별하여 균학적 특성을 조사하였다. 옥녀봉의 나뭇잎 20점으로부터 15종 22균주의 야생효모를 분리, 동정하였고 Cryptococcus bestiolae가 5주로 가장 많이 분리되었다. 또한 연자산 나뭇잎 20점에서는 모두 12종 24균주의 야생효모를 분리하였고 Aureobasidium pullulans가 8주로 가장 많았다. 옥녀봉과 연자산에서 분리한 야생효모 46균주 중에서 6종(Cryptococcus kuetzingii JSL508, Cryptococcus vishniacii JSL509, Dioszegia takashimae JSL510, Plowrightia periclymeni JSL514, Erythrobasidium hasegawianum JSL0193, Rhodotorula nothofagi JSL0196)을 국내에서 보고되지 않은 미기록 효모들로 최종 선별하였다. 이들의 균학적 특성을 조사한 결과 E. hasegawianum JSL0196은 자낭포자와 의균사를 형성하지 않았다. D. JSL510 외 모든 미기록 효모들은 내염성 또는 호염성이었고, C. JSL508과 D. JSL510은 $37^{\circ}C$에서 생육하는 고온성 효모들이었다.

• 미생물학회지
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• 제32권2호
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• pp.97-101
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• 1994

경기도, 충청남도 일원의 벼 근권에서 400~900nmol $C_2H_4/hr/vial$의 아세틸린 환원 활성을 갖는 질소고정균인 Azospirillum 15균주를 분리하였다. 이 분리균주들은 $1.0{\times}3.0{\mu}m$크기를 갖는 vibrioid 형태이었으며 액체배양시 monopolar single 편모를 가졌다. 이 분리균주들은 생리적, 형태적 특성에 따라 두 그룹으로 분류되었는데, 그룹 I 균주들은 탄소원으로 glucose를 잘 이용하였고 biotin 요구성인 반면, 그룹 II 균주들은 glucose를 전혀 이용하지 못하였고 biotin 비요구성이었다. 또한 semisolid 무질소 배지에서 48시간 배양할 때 그룹 I 균주들은 원래의 vibrioid 형태에서 좀 더 길어지면서 S자 모양으로 변하는 pleomorphic 특성을 보인 반면, 그룹 II 균주들은 원래의 모양과 운동성을 유지하였다. 이상의 결과로부터 그룹 I 균주들은 Azospirillum lipoferum으로, 그룹 II 균주들은 Azospirillum brasilense으로 동정하였다.

• 한국임상수의학회지
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• 제36권6호
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• pp.330-335
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• 2019

Apharyngostrigea ibis (Trematoda: Strigeidae) were obtained from the small intestine of two black-crowned night herons (Nycticorax nycticorax) and three grey herons (Ardea cinerea jouyi) between July 2006 and September 2018 in Daejeon metropolitan city and Kangwon province, Republic of Korea. The body is covered with a relatively thick cuticle, devoid of spines, and bipartite. The body measures at 2.3-3.33 × 0.86-1.20 mm, and the fore-body is ventrally concave. The oral sucker leads into a short esophagus that is devoid of a muscular pharynx. The worm was studied with a scanning electron microscope for the first time resulting in the detection of a pair of lappets located at the bilateral portion of the oral sucker. This is the first record of A. ibis in the Republic of Korea.

• 대한금속재료학회지
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• 제50권2호
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• pp.107-115
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• 2012

Direct laser melting (DLM) is a powder-based additive manufacturing process to produce parts by layer-by-layer laser melting. As the properties of the manufactured parts depend strongly on the deposited laser-melted bead, deposited layers obtained by the DLM process were characterized in this study. This investigation used a 200 W fiber laser to produce single-line beads under a variety of different energy distributions. In order to obtain a feasible range for the two main process parameters (i.e. laser power and scan rate), bead shapes of single track deposition were intensively investigated. The effects of the processing parameters, such as powder layer thickness and scan spacing, on geometries of the deposited layers have also been analyzed. As a result, minimum energy criteria that can achieve a complete melting have been suggested at the given powder layer thickness. The surface roughnesses of the deposited beads were strongly dependent on the overlap ratio of adjacent beads and on the energy distributions of laser power. Through microstructural analysis and hardness measurement, the morphological and mechanical properties of the deposited layers at various overlapped beads have also been characterized.

• 방사선산업학회지
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• 제5권1호
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• pp.7-13
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• 2011

The present study has been performed to compare the physiological analysis of monocot model plant (rice) in response to ionizing irradiations (cosmic-ray, gamma-ray, and Ion beam). Ionizing radiations were implanted into monocot model plant (rice) seed. After irradiation, the seeds were planted in the plastic pots for a growth period of one month. Thereafter, the morphological and physiological characteristics including malondealdehyde (MDA) and chlorophyll content, activities of antioxidant enzymes in irradiation samples were investigated. We are confirmed that the activity level of MDA and chlorophyll content were not changed by ionizing irradiation samples. However, the free radical contents were increased in all irradiated plants. And the activities of SOD, POD, and APX were significantly increased by irradiation compared with non-irradiation plant.

• 아시안잔디학회지
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• 제23권2호
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• pp.361-368
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• 2009

Cenangium ferruginosum 은 소나무류의 피목가지마름병의 원인균으로 알려져 있다. 한국에서 이 병은 1989년 처음 보고가 된 이래 2007년 봄 서울, 경기, 강원과 충북지역에서 대발생하였다. 병원균인 C. ferruginosum은 병원성이 약한 내생균으로 알려져 있으나 나무가 상처나 가뭄, 극심한 추위나 온난한 겨울 기후 등으로 인한 스트레스를 받게 되면 병 발생을 유발하게 된다. 본 연구에서는 기후변화에 따른 병 발생 동향을 이해하고자 국 내외 피목가지마름병 발생 현황 및 병원균의 특성을 설명하였다. 또한 경기, 충청, 경상지역의 발병한 잣나무 및 소나무의 병든 가지를 수집하여 병원균의 발달 과정을 관찰하였으며, 병원균을 분리하여 이들의 형태학적인 특성과 분자수준에서의 특성을 분석한 결과 C. ferruginosum 임을 확인할 수 있었다.

• The Plant Pathology Journal
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• 제37권5호
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• pp.465-475
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• 2021

The aim of this study was to characterize potential fungal species affecting mangrove species in Mexico. The phytopathogens were identified based on morphological and molecular characteristics using internal transcribed spacer (ITS1/ITS4) primers then sequenced and compared with the other related sequences in GenBank (NCBI). Three fungal species were identified as Colletotrichum queenslandicum (Weir and Johnst, 2012) from black mangrove (Avicennia germinans); Colletotrichum ti (Weir and Johnst, 2012) from white mangrove (Laguncularia racemosa) and buttonwood mangrove (Conocarpus erectus); Fusarium equiseti (Corda) from red mangrove (Rhizophora mangle). In addition, C. ti and F. equiseti were identified from mango Mangifera indica L. sampled close by the mangrove area. This study provides first evidence of anthracnose on four mangrove species caused by Colletotrichum and Fusarium species in the "Términos" coastal lagoon in Campeche State southern Mexico. This is the first time that C. queenslandicum and C. ti are reported in Mexico. F. equiseti has not been reported affecting M. indica and R. mangle until the present work. Little is known regarding fungal diseases affecting mangroves in Mexico. These ecosystems are protected by Mexican laws and may be threatened by these pathogenic fungus. This is the first report of the effect of Trichoderma harzianum TRICHO-SIN as an effective biological control against of Colletotrichum and Fusarium species.

• 한국임상수의학회지
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• 제38권2호
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• pp.75-81
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• 2021

An aquariid nematode, Desportesius invaginatus, was found in the proventriculus of an Egretta garzetta and a Bubulcus ibis from Chuncheon in the Republic of Korea. The worms were identified by light and scanning electron microscopy based on important taxonomic characteristics (body length, esophagus length, cordons, spicules, caudal alae of males, position of the vulva) and then phylogenetically analyzed using the 18S rRNA encoding gene. The nematodes were characterized by a body length of 7.0-8.0 mm in males and 10.2-13.1 mm in females, and two pairs of cordons recurrent in the anterior direction, and cordons were anastomosed by a longitudinal cuticular ridge that externally delimits a longitudinal canal. The widest cuticular plates of cordons bears over 20 posterior spines. The length of the spicules in males was also significantly different. The right spicule measured 742-821 (794) ㎛ in length and 40-45 (42) ㎛ in width, and the left spicule measured 493-556 (541) ㎛ in length and 11-13 (12) ㎛ in width. The caudal alae of males are inflated and vesicular in appearance. The vulva was situated at 56-71 (58.3) ㎛ from the posterior extremity. Although the 18S rRNA sequences of worms were similar to the Synhimantus species, some genetic divergences were observed in comparison. In this study, the worms were recognized with genus Desportesius because genus Desportesius was considered a subgenus of Synhimantus. This is the first record of D. invaginatus in the Republic of Korea.