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        25.
        2019.04 KCI 등재 구독 인증기관 무료, 개인회원 유료
        For electrodes in electrochemical double-layer capacitors, carbon nanofibers (CNFs) were prepared by thermal treatment of precursor polymer nanofibers, fabricated by electrospinning. Poly(acrylonitrile-co-vinylimidazole) (PAV) was employed as a precursor polymer of carbon nanofibers due to the effective cyclization of PAV polymer chains during thermal treatment compared to a typical precursor, polyacrylonitrile (PAN). PAV solutions with different comonomer compositions were prepared and electrospun to produce precursor nanofibers. Surface images obtained from scanning electron microscopy showed that their nanofibrous structure was well preserved after carbonization. It was also confirmed that electrospun PAV nanofibers were successfully converted to carbon nanofibers after the carbonization step by Raman spectroscopy. Carbon nanofiber electrodes derived from PAV showed higher specific capacitances and energy/power densities than those from PAN, which was tested by coin-type cells. It was also shown that PAV with an acrylonitrile/vinylimidazole composition of 83:17 is most promising for the carbon nanofiber precursor exhibiting a specific capacitance of 114 F/g. Their energy and power density are 70.1 Wh/kg at 1 A/g and 9.5 W/kg at 6 A/g, respectively. In addition, pouch cells were assembled to load the higher amount of electrode materials in the cells, and a box-like cyclic voltammetry was obtained with high capacitances.
        4,000원
        26.
        2019.04 구독 인증기관·개인회원 무료
        In this study, we sequenced two complete mitogenomes, belonging to the families Scythrididae (Scythris sinensis Felder & Rogenhofer, 1775) and Coleophoridae (Coleophora therinella Tengström, 1848) firstly in each family. Gelechioidea is one of the controversial lineages of Lepidoptera in its phylogenetic position and number of families. Phylogenetic analyses with concatenated sequences of the 13 PCGs and two RNA genes using the maximum likelihood method, placed Coleophoridae, represented only by C. therinella, as a sister group to the families Depressariidae and Autostichidae, with very low nodal support (7%). Scythrididae represented only by S. sinensis was placed as the sister to the family Stathmopodidae, with relatively high nodal support (86%). As more mitogenome sequences from the extended taxonomic groups are obtained further robust phylogenetic inference will be possible.
        27.
        2019.04 구독 인증기관·개인회원 무료
        DNA 바코드를 기반으로 하여 외국발 국내 입항 선박에서 검출되는 편승자 해충(hitchhiker insect pests)에 대한 모니터링을 수행하였다. 국내 입항 선박 조사는 2018년 6월 1일부터 2018년 9월 17일까지 약 109일간 111개 선박에 대해 실시하였다. 모니터링 대상 해충은 ‘보고잡기법(simply collecting method by hands)’으로 확보하였으며, 총 336개체 에 대해 종동정을 실시하였다. 그 결과, 확보 해충 중 농림축산검역본부에 ‘관리해충(Regulated insect pest)’으로 등재되어 있는 Noctua pronuba를 포함하여 총 13종 21개체(Amata formosae (Erebidae, Lepidoptera, 1개체), Arippara disticha (Pyralidae, Lepidoptera, 1개체), Chondracris rosea (Acrididae, Orthoptera, 4개체), Cyrtacanthacris tatarica (Acrididae, Orthoptera, 1개체), Euhampsonia serratifera (Notodontidae, Lepidoptera, 3개체), Lemyra rhodophilodes (Erebidae, Lepidoptera, 2개체), Lymantria xylina (Erebidae, Lepidoptera, 1개체), Malacosoma dentata (Lasiocampidae, Lepidoptera, 3개체), Neochauliodes meridionalis (Corydalidae, Megaloptera, 1개체), Noctua pronuba (Noctuidae, Lepidoptera, 1개체), Parasa pastoralis (Limacodidae, Lepidoptera, 1개체), Psilogramma lukhtanovi (Sphingidae, Lepidoptera, 1개체), Syntypistis viridipicta (Notodontidae, Lepidoptera, 1개체))의 국내 미서식종이 채집되었으며, 확보된 21개체 중 15개체는 살아있는 상태로 검출되었다. 특히, 관리해충인 N. pronuba의 경우, 싱가포르에서 광양을 거쳐 포항항으로 입항한 선박에서 검출되었는데, 이 종은 유럽을 비롯하여 중동 및 중앙아시아까지 서식하는 종으로 1990년대 북미 대륙에 침입한 것으로 확인된 바 있다. 이에 따라, N. pronuba를 비롯하여 현 조사에 확인된 국내 미서식 편승자 해충의 편승 유무에 대한 정밀 모니터링 뿐만 아니라 위 종들에 대한 체계적인 위험성 평가 역시 필요할 것으로 사료된다.
        30.
        2018.04 구독 인증기관·개인회원 무료
        The Acoptolabrus changeonleei Ishikawa et Kim, 1983 (Coleoptera: Carabidae), has been listed as an endangered insect in South Korea. The complete mitochondrial genome of the species was 16,831 bp with a typical set of genes (13 protein-coding genes [PCGs], 2 rRNA genes, and 22 tRNA genes) and one non-coding region, with the arrangement identical to that observed in most insect genomes. Phylogenetic analyses with concatenated sequences of the 13 PCGs and 2 rRNA genes, using the Bayesian inference (BI) and maximum-likelihood (ML) methods, placed A. changeonleei as a sister to the within-subfamilial species Damaster mirabilissimus in Carabinae, with the highest nodal support by both analyses.
        34.
        2016.04 구독 인증기관·개인회원 무료
        In order to understand evolutionary characteristics of gene rearrangement in Lepidoptera, we collected all available complete mitogenome (mitogenome) sequences registered in GenBank (274 mitogenomes from 44 families in 23 superfamilies as of August 6, 2015). It turned up six rearrangements that differ from the arrangement of ancestral insects, including that of the gelechioid Mesophleps albilinella that we sequenced in this study. The M. albilinella mitogenome has a unique gene arrangement among the Gelechioidea: ARNESF (the underline signifies an inverted gene) at the ND3 and ND5 junction, as opposed to the ARNSEF that is found in ancestral insects. Most of the rearrangements can be explained by the tandem duplication-random loss model, but inversion, which requires recombination, is also found in two cases, including M. albilinella. Excluding the MIQ rearrangement at the A+T-rich region and ND2 junction, which is found in nearly all Ditrysia, most of the remaining rearrangements found in Lepidoptera appear to be independently derived in that they are automorphic at several taxonomic scales. Current mitogenomic data are limited, particularly for congeneric data. Thus, future research focused on congenerics could clarify evolutionary independency at the generic level also.
        36.
        2015.10 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        Bi0.5Na0.5TiO3 (BNT) based ceramics are considered potential lead-free alternatives for Pb(Zr,Ti)O3(PZT) based ceramics in various applications such as sensors, actuators and transducers. However, BNT-based ceramics have lower electromechanical performance as compared with PZT based ceramics. Therefore, in this work, lead-free bulk 0.99[(Bi0.5Na0.5)0.935Ba0.065](1-x)LaxTiO3-0.01SrZO3 (BNBTLax-SZ, with x = 0, 0.01, 0.02) ceramics were synthesized by a conventional solid state reaction The crystal structure, dielectric response, degree of diffuseness and electric-field-induced strain properties were investigated as a function of different La concentrations. All samples were crystallized into a single phase perovskite structure. The temperature dependent dielectric response of La-modified BNBT-SZ ceramics showed lower dielectric response and improved field-induced strain response. The field induced strain increased from 0.17% for pure BNBT-SZ to 0.38 % for 1 mol.% La-modified BNBT-SZ ceramics at an applied electric field of 6 kV/mm. These results show that Lamodified BNBT-SZ ceramic system is expected to be a new candidate material for lead-free electronic devices.
        4,000원
        37.
        2015.10 구독 인증기관·개인회원 무료
        We sequenced the complete mitochondrial (mt) genome of Camponotus atrox (Hymenoptera: Formicidae) that is distributed only in Korea. This genome is 16,540 bp in size, contains typical sets of genes (13 protein-coding genes, 22 tRNAs, and two rRNAs). The C. atrox A+T-rich region is the longest in the sequenced ants as 1,402 bp and is comprised of an identical tandem repeat consisting of six 100-bp copies and one 96-bp copy. A total of 315 bp of intergenic-spacer sequences were spread over 23 regions. An attempt to align spacer sequences in ants turned out that alignment was mostly feasible among congeneric species, with a substantial sequence divergence, indicating the potential of these sequences as congeneric molecular markers. The A/T content in first and second codon positions of PCGs are similar in ants including C. atrox (73.9 vs. 72.3% on average). Estimation of degree of genetic divergence (e.g. non-synonymous substitution rate) with an increased taxon sampling among hymenopteran superfamilies indicated the presence of different rates of divergence between the suborders Symphyta and Apocrita as has previously been reported. The C. atrox mt genome has a unique gene arrangement, trnI-trnM-trnQ at the A+T-rich region and ND2 junction (underline for inverted gene), possibly originated from tandem duplication of trnM-trnI, resulting in trnM-trnI-trnM-trnI-trnQ and loss of first trnM and second trnI, resulting in trnI-trnM-trnQ.
        38.
        2015.06 KCI 등재 SCOPUS 구독 인증기관 무료, 개인회원 유료
        New lead-free piezoelectric ceramics 0.96[{Bi0.5 (Na0.84 K0.16)0.5}1-xLax(Ti1-y Nby)O3]-0.04SrTiO3 (BNKT-ST-LN, where x = y = 0.00 ≤ (x = y) ≤ 0.015) were synthesized using the conventional solid-state reaction method. Their crystal structure, microstructure, and electrical properties were investigated as a function of the La and Nb (LN) content. The X-ray diffraction patterns revealed the formation of a single-phase perovskite structure for all the LN-modified BNKT-ST ceramics in this study. The temperature dependence of the dielectric curves showed that the maximum dielectric constant temperature (Tm) shifted towards lower temperatures and the curves became more diffuse with an increasing LN content. At the optimum composition (LN 0.005), a maximum value of remnant polarization (33 C/cm2) with a relatively low coercive field (22 kV/cm) and high piezoelectric constant (215 pC/N) was observed. These results indicate that the LN co-modified BNKT-ST ceramic system is a promising candidate for lead-free piezoelectric materials.
        4,000원
        39.
        2015.04 구독 인증기관·개인회원 무료
        Entomopathogenic Beauveria bassiana and Metarhizium anisopliae are well-known biological control agents worldwide and have high potential in industrialization. However their thermo-susceptibility limits long-term storage under high temperature conditions and high insecticidal activity after application to target pests. Herein we isolated highly virulent isolates, B. bassiana JEF006 and JEF007 and M. anisopliae JEF003 and JEF004, and produced in three grains, such as sorghum, millet and Italian millet as substrates for solid cultures, followed by thermotolerance assays to compare the potential of the three substrates for thermotolerance. The JEF isolates were exposed to dry and wet heat at 50°C and overall conidia were more stable under dry heat condition rather than wet heat. Of the three grains, Italian millet was superior to the other grains in the production of thermotolerant conidia. Additionally Italian millet did not severely aggregated, which enabled air to penetrate into the substrate well compared to the sorghum and millet. JEF isolates were more thermotolerant when they were kept in oil conditions as carriers of an oil-based formulation. This work suggests that Italian millet can be used as an effective substrate to produce more thermotolerant conidia, thus maintaining viability for long times under unfavorable environment and biological activity against target pests.
        40.
        2013.10 구독 인증기관·개인회원 무료
        Glyphodes quadrimaculalis (Lepidoptera: Crambidae) feed on a root tuber of Cynanchum wilfordii (Asclepiadaceae) that is one of the most famous traditional medicines in Korea. The genus Glyphodes includes ~130 species distributed worldwide, so the complete mitochondrial genome (mitogenome) would be helpful for bio-identification, biogeographic studies, and multigene-based phylogeny. The 15,255-bp long G. quadrimaculalis genome comprises 37 typical genes and one large non-coding region, with the typical arrangement found in Lepidoptera. Of the 13 protein coding genes (PCGs), 12 begin with typical start codons found in insect mitochondrial PCGs, but the COI gene starts with atypical CGA. One of the noteworthy features of the genome includes the presence of a 51-bp long non-coding space sequence located between tRNAGln and ND2 that reveals high sequence homology (71.4%) to the neighboring ND2 gene, indicating the origin of the region by partial duplication of the ND2 gene.
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