• Nano
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• 제13권11호
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• pp.1850125.1-1850125.12
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• 2018

To reduce the imbalance of impedance matching between the magnetic metal nanowires and free space, $Fe/TiO_2$ core/shell nanowire arrays with different diameters were fabricated in the templates of anodic aluminum oxide membranes by electrodeposition. The influences of the microstructure on the microwave absorption properties of the $Fe/TiO_2/Al_2O_3$ composites were studied by the transmission/reflection waveguide method. It was demonstrated experimentally that both the interfacial polarization and the diameter of the $Fe/TiO_2$ core/shell nanowires have critical effects on the microwave absorption properties. We also investigated the angle dependence of the microwave absorption properties. Due to the interfacial polarization and associated relaxation, the $Fe/TiO_2/Al_2O_3$ composites exhibited optimal microwave absorption properties when microwave propagation direction was accordant with the axis of the nanowires. Finally, we managed to obtain an optimal reflection loss of below -10 dB (90% absorption) over 10.2-14.8 GHz, with a thickness of 3.0 mm and the minimum value of -39.4 dB at 11.7 GHz.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.13-13
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• 2022

Recently, stable crop production is threatened by the effects of climate change. In particular, it is difficult to consistently maintain agricultural policies due to large price fluctuations depending on the difference in total domestic rice production from year to year. For stable rice production amid changes in the crop growing environment, development of varieties with improved disease resistance and abiotic stress stability is becoming more important. In here, drought and cold tolerant trait have been studied. First, for the development of drought tolerant varieties, we analyzed which agricultural traits are mainly affected by domestic drought conditions. As a result, it was observed that drought caused by the lack of water during transplanting season inhibits the development of the number of tiller and reduces the yield. 'Samgang' was selected as a useful genetic resource with strong drought tolerant and stable tiller number development even under drought conditions by phenotype screening. Three of drought tolerant QTLs were identified using doubled haploid (DH) population derived from a cross between Nacdong and Samgang, a drought sensitive and a tolerant, respectively. Among these QTLs, when qVDT2 and qVDTl1 were integrated, it was investigated that the tiller number development was relatively stable in the rainfed paddy field conditions. It is known that the high-yielding Tongil-type cultivars are severely affected by cold stress throughout the entire growth stage. In this study, we established conditions that can test the cold tolerance phenotype with alternate temperature to treat low temperatures in indoor growth conditions similar to those in field conditions at seedling stage. Three cold tolerant QTLs were explored using population derived from a cross between Hanareum2 (cold sensitive variety, Tongil-type) and Unkwang (cold tolerant variety, Japonica). Among these QTLs, qSCT12 showed strong cold tolerant phenotype, and when all of three QTLs were integrated, it was investigated that cold tolerant score was relatively similar to its donor parent, Unkwang, in our experimental conditions. We are performing that development of new variety with improved cold tolerant through the introduction of these QTLs.

• 한국자원식물학회:학술대회논문집
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• 한국자원식물학회 2020년도 추계국제학술대회
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• pp.63-63
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• 2020

Rice stripe virus (RSV) disease is one of the major constraints in rice production, transmitted by the small brown planthopper (SBPH; Laodelphax striatellus). Upon RSV infection, plants develop typical symptoms, which include chlorosis and weakness of newly emerged leaves, white and yellow spots, stripe on leaves, and necrotic and wilting leaves, resulting in plant growth inhibition, oxidative damage that may culminate in programmed cell death (PCD) and plant death in severe epidemics. Although RSV-resistant quantitative trait loci (QTLs), Stv-a, Stv-b, and Stv-bi, were mapped using various resistant varieties, one RSV-resistant gene, OsSOT1, has been identified so far. In this study, we used the rice cultivar Zenith, known to carry Stv-b, to investigate novel RSV-genes through fine mapping. Therefore, we crossed Zenith (Donor parent, RSV resistant) with Ilpum (Recurrent parent, RSV susceptible) to fine-map using a BC₂F₂ population of 2100 plants. Chromosome segment introgression lines that were heterozygous at a different region were selected, two types of heterozygous lines showed an heterozygous genotype between Sid2 and Sid75 to Indel9 and RM6680. Interestingly, we identified qSTV11^Z region harboring Stv-b, covering about 171-kb region between the InDel markers Sid75 and Indel8. The localization of qSTV11^Z provides useful information that could be used for marker-assisted selection and determination of genetic resources in rice breeding.

• 한국지열·수열에너지학회논문집
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• 제19권4호
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• pp.1-7
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• 2023

In Korea, it is also mandatory for most buildings to receive energy efficiency rating certification from 2020 for the purpose of reducing greenhouse gas emissions and expanding green buildings. However, the issue of the accuracy of the ECO2 program continues to be raised, and comparisons have been made with dynamic energy analysis programs in a single type of building according to a single area. However, comparisons between multiple building types and multiple areas are insufficient. Therefore, in this study, cooling and heating loads according to multiple building types and multiple areas were analyzed through ECO2 and TRNSYS programs. The regions were supposed to be Seoul, Daejeon, Gwangju, and Busan and the building types were supposed to be office buildings and apartment houses. The annual average building load values from ECO2 were higher than those from TRNSYS. Among residential buildings across the four regions, the largest discrepancy was 41.4% in Seoul. Conversely, for commercial buildings, the most significant difference in annual average loads was noted in Gwangju, at 37.9%.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.96-96
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• 2017

Rice is a staple food for nearly half of the world's population, with more than 10,000 rice varieties providing almost one-quarter of the global per capita dietary energy supply. Grain size, panicle size and branch number, grain number in a panicle are directly associated with rice productivity. Recently several genes which increase grain yield were identified through map-based cloning. Gn1a, Cytokinin oxidase, is a major grain number QTL and regulates grain number per panicle. Dep1 increases panicle branching and reduced rachis length. SCM2 (APO1) was identified by a QTL for culm strength and increased spikelet number. OsSPL16 (GW8) controls grain size and shape and then increases 1000-weight of seed. In here, to identify genotype of genes related to yield in 400 of rice germplasms possessed in National Institute of Crop Science, we had first chosen 4 of well-known genes related to yield; Gn1a, Dep1, SCM2, and OsSPL16. Among these germplasms, 195, 382, 165, and 353 of germplasms harbored the dominant type of Gn1a, Dep1, SCM2, and OsSPL16, respectively. We grouped these germplasms into a total of 10 groups using genotypes of Gn1a, Dep1, SCM2 and OsSPL16. Most rice germplasms belong to group 1, harbored Gn1a, dep1, gw8 and APO1, and group 10, harbored gn1a, Dep1, GW8 and apo1. Hanareum2 is the highest productive cultivar in Korea but do not have dominant type OsSPL16, so belong to group 1. On the other hand, in the case of Unkwang, belongs to group 10, which has dominant type of OsSPL16 but do not have the remaining genes. We can grasp the differences in rice germplasms through the Profiling of genes related to these grain yield, which will be useful for cross-breeding to integrate grain yield genes. We are continuously observing the genotype and phenotype of rice that possesses grain yield genes.

• 한국응용곤충학회지
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• 제41권2호
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• pp.113-121
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• 2002

벼멸구를 저항성 품종에서 도태시켰을 때 새로운 생태형으로 발전되는 속도와 벼멸구의 생태형과 벼의 품종저항성 간에 유전적으로 대응하고 있는지를 알아보고자, 감수성품종(동진벼)으로 사육하던 벼멸구를 Bph1 gene을 가진 저항성품종(청청벼)으로 각각 3세대 및 6세대 도태시킨 후, 같은 Bph1 gene을 가진 4개 품종(Mudgo, IR26, IR64, 청청벼)과, 다른 bph2 gene을 가진 2개 품종(밀양63호 및 가야벼)및 저항성이 없는 2개 품종(동진벼, TN-1)을 공시하여 각 계통의 벼멸구의 산란 및 섭식선호성, 수명, 발육기간, 사충율, 산란수 등을 조사하였다. 그 결과 감수성 벼멸구(생태형-1)를 저항성 Bph1 유전자를 갖인 청청벼에서 3세대(청청3세대계)및 6세대(청청6세대계)로 도태시켰을 때, 사육세대가 많아질수록 청청벼에서의 성충의 수명은 길어지고, 산란수는 많아지며, 또한 약충의 우화율이 높아지고, 약충기간이 짧아지는 등 빠르게 저항성을 극복하였다. 청청3세대계 및 6세대계 벼멸구는 청청벼와 같은 Bph1저항성 유전자를 가진 다른 품종들(Mudgo, IR26, IR64)에 대해서도 도태세대수가 많아지면서 선호성이 점점 높아지는 경향이었다. 성충의 수명과 산란수에 있어서도 청청3세대계, 청청6세대계 등으로 도태세대가 많아질수록 같은 저항성 Bph1유전자를 가진 Mudgo, IR26, IR64등에서 수명이 길어지고 산란수도 많아졌다. 벼멸구의 약충기간은 품종과 벼멸구 도태계통간에 큰 차이가 없었다. 그러나, 약충기간 중 사망률은 도태가 진행되면서 역시 Bph1저항성 gene의 4개 품종 모두에서 낮아졌고, 죽은 개체의 수명도 길어졌다. 밀양 63호(bph2 gene)와 가야벼(Bph1+bph2 gene) 등 2개 품종에서는 벼멸구의 3개 계통 모두 우화하지 못했다.

• Applied Biological Chemistry
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• 제49권4호
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• pp.287-292
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• 2006

명조건과 암조건에서 카드뮴이 벼 유묘 뿌리와 줄기의 카탈라제 총 활성과 동위효소 발현에 미치는 영향을 조사하였다. 카드뮴을 처리하면 명조건과 암조건의 뿌리와 줄기에서 과산화수소 함량이 현저하게 증가하였다. 뿌리의 카탈라제 동위효소는 잎과는 서로 다른 조직 특이적 발현양상을 보여주었다. 또한 카드뮴을 처리하게 되면 명조건 뿌리는 암조건 뿌리와 카탈라제 동위효소의 발현 패턴에 차이를 보였다. 1 mM 카드뮴 처리에 의하여 명조건 뿌리의 카탈라제 총 활성은 약 16배 증가하였는데 이러한 활성증가는 동위효소 CAT1l과 CAT2의 증가에 의한 것이었다. 반면 암조건 뿌리의 카탈라제는 0.1mM 카드뮴에 의하여 약 3배 증가하였느나, 0.5와 1mM카드뮴에 의하여 오히려 효소활성이 감소하였다. 0.1mM카드뮴에 의한 효소활성 증가는 CAT1, CAT3, CAT4 동위효소의 활성 증가에 기인하였으나 카드뮴 농도를 더 높였을때 CAT2와 CAT4가 감소하였다. 대조군 잎에는 양극 동위효소인 CATc, 중성 동위효소인 CATn와 음극 동위효소인 CAT1가 존재하였다. 잎에서는 명조건과 암조건 모두에서 카드뮴을 처리하여도 카탈라제 활성과 동위효소 발현에 차이가 없었다. 이러한 결과들은 카드뮴에 의한 뿌리 카탈라제 효소의 발현변화는 빛에 의하여 조절되지만 잎 카탈라제의 발현은 빛에 의하여 조절되지 않음을 보여준다.

• 한국해양학회지
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• 제30권2호
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• pp.77-90
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• 1995

한국 서해 동진강-만경강 하구역과 인접 연안역에 발달한 조간대의 퇴적환경과 생 층서에 대하여 연구지역에서 채취한 5개의 진동시추코아 퇴적환경과 생층서에 대하여 연구지역에서 채취한 5개의 진동시추코아 퇴적물의 퇴적상과 규조군집분석을 통해 연 구하였다. 시추공 퇴적물은 주로 니질 및 사질로 조성되어 있으며 생혼퇴적 구조와 교 호엽총리, 후라저총리, 연흔사총리등의 퇴적구조들이 여러 층들에서 관찰된다. 전체 적으로 니질퇴적층이 사질퇴적층보다 우세하며 사질층을 제외한 대부분의 지질퇴적층 에는 다수의 규조각들이 함유되어 있다. 총 61속 219종 및 변종의 규조가 동정되었으 며 산출되는 규조중 가장 다산되는 종은 Paralia sulcata 이다. 그외 Cyclotella striata Thalassionema nitzschioides Actinoptychus undulatus, Delphineis surirella, Rhaphoneis amphiceros 등이 다산된다. 산출되는 대부분의 규조는 기수 및 해수역의 연안 혹은 천해에서 서식하는 저서성 및 우연적 혹은 부분적 부유성종이다. 담수종은 1∼5%정도로 남양만 조간대에 대해 높은 산출을 보인다. 규조류의 알려진 생 태와 여러 충준에서 관찰되는 교호엽총리, 후라저총리, 연혼사총리등의 퇴적구조는 본 연구 퇴적층이 하천수의 유입을 어느 정도 받고 한수 보다는 난수의 영향을 더 강하게 받는 조간대 환경하에서 퇴적된 것으로 추정된다. 그리고 생태적 측면에서 규조군집의 수직적 변화가 인지되지 않는 것으로 보아 퇴적기간 동안 퇴적환경의 뚜렷한 변화는 없었던 것으로 생각된다. Q-mode을 이용한 규조군집 부산광역시 결과 각 시추공 별로 각각 2개의 군집으로 분류되었으며 이들 군집으로 분류되었으며 이들 군집들의 충위적 분포를 근거하여 시추공간의 생충서적 대비를 시도해 보았다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.98-98
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• 2017

Leaf senescence is the process of aging in plants. Chlorophyll degradation during leaf senescence has the important role translocating nutrients from leaves to storage organs. The functional stay-green with slow leaf yellowing and photosynthesis activity maintenance has been considered one of strategy for increasing crop productivity. Here, we have identified two QTLs on chromosome 9 and 10 for leaf senescence with chlorophyll content of RIL population derived from a cross between Hanareum 2, early leaf senescence Indica-type variety, and Unkwang, delayed leaf senescence Japonica variety. Among these QTLs, we chose qPLS1 QTL on chromosome 9 for further study. qPLS1 was found to explain 14.4% of the total phenotypic variation with 11.2 of LOD score. Through fine-mapping approach, qPLS1 QTL locus was narrowed down to about 25kb in the marker interval between In/del-4-7-9 and In/del-5-9-4. There are 3 genes existed within 25kb of qPLS1 locus: LOC_Os09g36200, LOC_Os09g36210, and LOC_Os09g36220. Among these genes, transcript level of LOC_Os09g36200 was increased during the leaf senescence stage and the expression level of LOC_Os09g36200 in Indica was higher than in Japonica. Finally, we chose LOC_Os09g36200 as candidate gene and renamed it as OsPLS1-In and OsPLS1-Jp from Indica- and Japonica-type rice, respectively. OsPLS1-In and OsPLS1-Jp overexpressing transgenic plants showed both early leaf senescence phenotype. These results indicate that OsPLS1 functions in chlorophyll degradation and the difference of expression level of OsPLS1 cause the difference of leaf senescence between Indica and Japonica in rice.

• 에너지공학
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• 제25권3호
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• pp.66-72
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• 2016

본 연구에서는 술폰화된 sodium 5,5'-carbonylbis(2-fluorobenzene sulfonate) 단량체를 이용하여 친수성 올리고머를 합성한 뒤 소수성 올리고머와 1:1로 공중합반응을 시켜 sulfonated poly(arylene ether ketone) (SPAEK) 공중합체를 합성하였다. 제조한 공중합체의 구조 분석은 $^1H$-NMR, FT-IR, GPC를 사용하여 실시하였고, GPC에서 공중합체의 평균분자량은 $209,700g\;mol^{-1}$, 다분산지수(PDI)는 1.25이었다. 열적 안정성을 확인하기 위하여 TGA 분석을 실시하였고, $200^{\circ}C$이상에서의 열 안정성을 확인하였다. 고분자 전해질 막의 양이온 전도도는 상대습도 100%, $80^{\circ}C$의 온도에서 약 $9.0mS\;cm^{-1}$이었다. 측정된 결과로부터 본 연구에서 제조한 탄화수소계 전해질 막은 술폰화 정도를 증가시키거나 약간의 구조적 변형을 통해 연료전지용 고분자 전해질 막으로 적용 가능할 것으로 기대된다.