• Mycobiology
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• 제48권6호
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• pp.484-494
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• 2020

Oak wilt disease caused by Raffaelea quercus-mongolicae has emerged obviously in Korea. We selected antifungal isolates against R. quercus-mongolicae among 368 endophytic fungal isolates from different parts of oak and pine trees. The experiment was conducted in the primary and secondary screenings by dual culture test. The antifungal activity of the selected isolates was assessed in culture filtrate test based on the inhibition rates in mycelial growth, sporulation, and spore germination of oak wilt fungus. Five isolates, E089, E199, E282, E409 and E415, showed strong antifungal activity in culture filtrate test, and their antifungal activity decreased on the culture media supplemented with heated culture filtrate. Higher mycelial growth inhibitions on the unheated media were recorded in E409 (Colletotrichum acutatum), E089 (Daldinia childiae), E415 (Alternaria alternata) and E199 (Daldinia childiae) with the inhibition rates of 79.0%, 70.1%, 68.9% and 64.5%, respectively. These isolates also had the higher sporulation inhibitions on unheated media with the rates of 96.8%, 84.2%, 82.8% and 80.5%, respectively. The spore germination of the oak wilt fungus was completely inhibited by E282 (Nectria balsamea) on both unheated and heated media. These results showed that a higher number of potent antifungal isolates against oak wilt fungus was isolated from the petiole compared to the other parts. This study could contribute to the development of biological control approaches for the management of oak wilt disease caused by R. quercus-mongolicae.

• 한국초전도저온공학회:학술대회논문집
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• 한국초전도저온공학회 2002년도 학술대회 논문집
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• pp.340-340
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• 2002

In an effort to develop alternative single buffer layer technology for YBa$_2$Cu$_3$O$_{7-{\delta}}$ (YBCO) coated conductors, we have investigated both LaMnO$_3$, (LMO) and La$_2$Zr$_2$O$_{7}$ (LZO) as potential buffer layers. High-quality LMO films were grown directly on textured Ni and Ni-W (3%) substrates using rf magnetron sputtering. Highly textured LZO buffers were grown on textured Ni substrates using sol-gel alkoxide processing route. YBCO films were then grown on both LMO and LZO buffers using pulsed laser deposition. Detailed X-ray studies have shown that YBCO films were grown on both LMO and LZO layers with a single epitaxial orientation. A high J$_{c}$ of over 1 MA/cm$^2$ at 77 K and self-field was obtained on YBCO films grown on both LMO-buffered Ni or Ni-W substrates, and also on LZO-buffered Ni substrates. We have identified LaMnO$_3$ as a good diffusion barrier layer for Ni and it also provides a good template for growing high current density YBCO films. Similarly we have also demonstrated the growth of high J$_{c}$ YBCO films on all solution buffers. We will discuss in detail about our buffer deposition processes. processes.s.s.s.s.

• 한국초지조사료학회지
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• 제22권1호
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• pp.59-68
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• 2002

본 연구는 산림부산물인 지엽류를 보다 효율적으로 활용할 수 있는 방안을 모색하고자 졸참나무지엽과 소나무지엽에 대한 사료가치를 구명하였으며 그 결과를 요약하면 다음과 같다. 일반조성분인 조단백질 함량은 참나무지엽과 소나무지엽이 각각 6.00∼7.89%, 5.15∼6.06%로 참나무지엽이 다소 높았으며 생육이 진행됨에 따라 참나무지엽은 감소하였으나 소나무지엽은 생육시기에 크게 영향을 받지 않았다. 조지방 함량은 각각 1.90∼2.68%, 6.30∼6.33%로 소나무지엽이 현저하게 높은 수준이었고, 조섬유 7 함량은 각각 33.3∼35.2%, 33.7∼34.8%로 비슷하였으며 생육이 진행됨에 따라 증가하는 경향이었다. 그리고 조회분 함량은 각각 3.13∼2.78%, 2.11∼l.93%로 참나무지엽이 약간 높았다. 무기물 함량은 Ca, Mg, Mn, Cu가 소나무 지엽보다 참나무지엽이 높은 수준이었고 P, K, Na, Fe, Zn은 비슷한 수준이었으며 생육이 진행됨에 따라 대부분 감소하는 경향이었다. 소나무지엽과 참나무지엽의 ABF 함량은 각각 47.7∼52.0%, 46.1∼48.1%로 비슷하였으며 생육이 진행됨에 따라 증가하였고(P<.05), NDF 함량은 각각 64.1∼67.9%, 65.0∼66.5%로 비슷하였으며 생육이 진행됨에 따라 소나무지엽은 증가하였으나(P<.05) 참나무지엽은 비슷하였다. 건물소화율은 소나무지엽이 51.7∼48.4%로 생육이 진행됨에 따란 감소하였고, 참나무지엽은 53.0%∼51.4%로 비슷하였다. 가소화양분층량은 참나무지엽이 50.9∼52.4% 이었고, 소나무지엽은 47.7∼51.1%로 생육이 진행됨에 따라 감소하였으며(P<.05), 상대적 사료가치는 참나무지엽과 소나무지엽이 비슷하였고 생육이 진행됨에 따라 낮아지는 경향이었다. 탄닌 함량은 참나무지엽과 소나무지엽이 각각 2.96%, 6.27%로 소나무지엽이 높았으며 지엽을 건조하였을 때 각각 2.46%, 4.79%로 탄닌 함량이 낮아지는 경향이었다.

• 한국가구학회지
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• 제21권1호
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• pp.54-61
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• 2010

This study was carried out to identify the differences of some macro and microanatomical features between Eunsasi poplar (Populus tomentiglandulosa T. Lee) and Konara oak (Quercus serrata Thunb.). Anatomical features such as vessel and fiber diameter, cross sectional area of ray parenchyma and endwall pit aperture diameter in ray parenchyma were compared. Differences of anatomical features between two species were found statistically significant. Earlywood vessel diameter in poplar and oak increased from pith to bark while it was found almost stable in latewood. Fiber diameter in poplar was higher than oak fiber. Ray area and the pit aperture diameter in endwall of ray parenchyma were found higher in oak than those in poplar.

• Advances in nano research
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• 제4권3호
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• pp.157-165
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• 2016

The photocatalytic (PC) activity of anatase titania nanoparticles can be improved through codoping with transition metals and nitrogen. In addition, the PC activity can also be improved by creating monodisperse, mesoporous nanoparticles of titania. The question naturally arose as to whether combining these two characteristics would result in further improvement in the PC activity or not. Herein, we describe the synthesis and photocatalytic characteristics of codoped, monodisperse anatase titania. The transition metals tested in the polydisperse and the monodisperse forms were Mn, Co, Ni, and Cu. In each case, it was found that the monodisperse version had a higher PC activity compared to the corresponding polydisperse version.

• Mycobiology
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• 제41권4호
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• pp.245-247
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• 2013

The ambrosia beetle, Platypus koryoensis, is an economically important pest affecting oak trees in Korea. Candida kashinagacola was isolated from galleries of the beetle in oak wood and identified by analyses of morphology, physiological properties, and nucleotide sequence of the large subunit ribosomal DNA. This is the first report on Candida species associated with oak wilt disease vectored by the ambrosia beetle, Platypus koryoensis, in Korea.

• 한국응용곤충학회지
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• 제45권2호
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• pp.113-117
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• 2006

2004년에 우리나라에 처음 발생이 확인된 참나무시들음병을 매개하는 광릉긴나무좀(Platypus koryoensis (Murayama))과 일본에서 참나무시들음병을 매개하는 Platypus quercivorus (Murayama) 성충의 형태적 특징을 도해와 함께 비교하였고, 동북아지역의 참나무시들음병과 관련된 매개충에 대하여 앞으로의 연구방향을 제언하였다.

• Journal of Plant Biology
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• 제20권3호
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• pp.109-118
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• 1977

Seasonal distribution of N, P and K contents and their cycling were studied in Korean oak (Quercus acutissima) and Korean alder (Alnus sibirica) stands in central part of Korean peninsula. The amounts of three minerals were high in young leaves but gradually decreased with the process of leaf development in both stands. The amounts of minerals in the branches, trunks and roots were decreased in summer, however, they increased again in autumn. Seansonal changes of these minerals were not significant in the two stands. The amounts of phosphorus and potassium in plant and soil were higher in the oak stand than the alder one, but those of nitrogen were reversed. The amounts of minerals absorbed during one year were greater in the oak stand than in the alder one, but those returned into soil through mineralization of litter were less in the former than in the latter. The nutrient requirements of the oak stand were greater than the alders, but the cycling rate, the ratio of the amount of minerals absorbed to returned, was opposite.

• 동아시아식생활학회지
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• 제21권5호
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• pp.669-676
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• 2011

This study was conducted to develop a novel salad dressing composite recipe composed of natural seasoning containing dried oak mushroom (Lentirus edodes). Dried oak mushroom (Lentirus edodes) has a better flavor and more nutrients than fresh oak mushroom since vitamins are activated during the drying process. To manufacture salad dressing with Lentirus edodes, dressing with 0%, 3%, 6%, 9%, and 12% added L. edodes were prepared and tested for quality. The pH of the dressing decreased with added L. edodes content, whereas acidity increased but decreased again in the 9% dressing. The L value decreased with added L. edodes content, whereas the a and b values increased but decreased again in the 9% dressing. Sugar content increased with added L. edodes. Rradish strength increased with added oak mushroom. Brittleness and chewiness decreased in the lower percentage dressing, increased in the 9% dressing, but decreased again in the 12% dressing. According to the sensory evaluation results, the highest overall acceptability was 3.3, in the 6% dressing compared to the control group.

• The Korean Journal of Ecology
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• 제26권6호
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• pp.327-333
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• 2003

A mixed forest of pines (Pines densiflora and Pinus rigida) and an oak forest (Quercus mongolica) in Mt. Kwanak in Seoul were limed with 1.5 t/ha and 3 t/ha of dolomite in 1993 and investigated the effects of liming on the chemical changes in the 0-5 cm and 5∼10 cm layers of soil from 1994 to 1995. Soil pH values were greater in the limed plots than in the control plot by the unit of 0.1-0.6 in the pine forest and 0.1∼0.2 in the oak forest. Ca concentrations in the limed plots were greater than those in the control plots in both the pine and oak forests. A considerable increase in Mg concentrations in soil was observed in the limed plots. K and Na concentrations in the limed plots appeared to decrease in both the pine and oak forests two years after liming. Although Al concentrations were greater in the limed plots than in the control plot in the pine forest in 1994, there was a tendency of a decrease in the concentration of this metal in the limed plots in 1995. Mn concentrations also tended to decrease in the limed plots in both the pine and oak forests.