• Title/Summary/Keyword: isolation wall

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Study on the Electrode Design for an Advanced Structure of Vertical LED (Via-hole 구조의 n-접합을 갖는 수직형 발광 다이오드 전극 설계에 관한 연구)

  • Park, Jun-Beom;Park, Hyung-Jo;Jeong, Tak;Kang, Sung-Ju;Ha, Jun-Seok;Leem, See-Jong
    • Journal of the Microelectronics and Packaging Society
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    • v.22 no.4
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    • pp.71-76
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    • 2015
  • Recently, light emitting diodes (LEDs) have been studied to improve their efficiencies for the uses in various fields. Particularly in the aspect of chip structure, via hole type vertical LED chip is developed for improvement of light output power, and heat dissipations. However, current vertical type LEDs have still drawback, which is current concentration around the n-contact holes. In this research, to solve this phenomenon, we introduced isolation layer under n-contact electrodes. With this sub-electrode, even though the active area was decreased by about 2.7% compared with conventional via-hole type vertical LED, we could decrease the forward voltage by 0.2 V and wall-plug efficiency was improved approximately 4.2%. This is owing to uniform current flow through the area of n-contact.

Selection of High Efficient Enzyme for Protoplasts Isolation from Mushrooms (버섯류의 원형질체 나출을 위한 고효율 효소 선발)

  • Kim, Jong-Kun;Kim, Jin-Hee;Kong, Won-Sik;Kang, Hee-Wan
    • The Korean Journal of Mycology
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    • v.38 no.1
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    • pp.21-24
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    • 2010
  • This study was carried out to select cell wall degrading enzymes for maximizing protoplast yield from Basidiomycetes. The protoplasts were released from spore suspension, mycelia cultured on cellophane membrane, and homogenized mycelia of Flammulina velutipes using commercial cell wall degrading enzymes. The highest yield of protoplasts was obtained from the homogenized mycelia treated with the enzyme combination of $Glucanex^R$ 200G and cellulase onozuka R-10. The protocol was also available for Pleurotus ostreatus, P. eryngii, and Hypsizygus marmoreus.

Isolation of an Invertebrate-type Lysozyme from the Body Wall of Spoon Worm, Urechis unicinctus (개불의 체벽으로부터 i-type 라이소자임의 정제)

  • Oh, Hye Young;Park, Nam Gyu
    • Journal of Life Science
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    • v.28 no.3
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    • pp.300-306
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    • 2018
  • Lysozymes are innate immune factors that play a critical role in the defense against pathogens in various invertebrate animals including spoon worms. In this study, an invertebrate-type lysozyme was isolated from the body wall of spoon worm, Urechis unicinctus. The acidified body wall extract was partially separated using a Sep-Pak C18 cartridge. Among the fractions, the materials that were eluted with 60% methanol/0.1% trifluoroacetic acid showed the most potent antimicrobial activity against Bacillus subtilis KCTC 1021. A series of high performance liquid chromatography (HPLC) steps were then utilized to isolate a single antimicrobial absorbance peak. The molecular weight of the antimicrobial peak was approximated using sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), which was approximately 13 to 14 kDa. The partial primary structure of this antimicrobial protein that was analyzed, using LC-MS/MS, was CTGGRPPTCEDYAK (1611.69 Da). Homology search of these fourteen residues, using the National Center for Biotechnology Information Basic Local Alignment Search Tool (NCBI BLAST), revealed that the isolated protein was similar to the invertebrate-type lysozymes described in other animals. Then, the antimicrobial and lysozyme enzymatic (muramidase) activities of this protein were assessed. The isolated protein possessed antimicrobial activity and potent muramidase activity, which were comparable to those of hen egg white lysozyme. Therefore, the isolated protein was designated as Urechis unicinctus invertebrate-type lysozyme from the body wall, Uu-iLysb.

Isolation and Characterization of Lethal Mutation near the unc-29 (LG I) Region of Caenorhabditis elegans

  • Lee, Jin-Sook;An, Joo-Hong
    • Animal cells and systems
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    • v.2 no.1
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    • pp.123-131
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    • 1998
  • The unc-29 region on the chromosome I of Caenorhabditis elegans has been mutagenized in order to obtain lethal mutations. In this screen, the uncoordinated phenotype of unc-29 (e193) mutant was used to identify any lethal mutations closely linked to the unc-29 gene, which encodes a subunit of nicotinic acetylcholine receptors. We have isolated six independent mutations (jh1 to jh6) out of approximately 5,200 ethyl methanesulfonate(EMS) treated haploids. Four of the six mutations demonstrated embryonic lethal phenotypes, while the other two showed embryonic and larval lethal phenotypes. Terminal phenotypes observed in two mutations (jh1 and jh2) indicated developmental defects specific to posterior part of embryos which appeared similar to the phenotypes observed in nob (no back end) mutants. Another mutation (jh4) resulted in an interesting phenotype of body-wall muscle degeneration at larval stage. These mutations were mapped by using three-factor crosses and deficiency mutants in this region. Here we report genetic analysis and characterization of these lethal mutations.

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Isolation of Cadmium-tolerant Bacteria and Accumulation of Cadmium into the Bacterial Cell (카드뮴의 내성균분리 및 균체내 축적)

  • 김영배;이수래
    • Microbiology and Biotechnology Letters
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    • v.4 no.3
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    • pp.111-115
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    • 1976
  • A strain of Enterobacter cloacae isolated from soil showed the evidence of growth in medium containing 1,500 ppm of Cd$\^$++/ though its growth was inhibited at high cadmium concentrations. This strain accumulated 59% of cadmium into the cells during incubation in medium containing 0.5 ppm of cadmium and its uptake was nearly proportional to the dry weight of cells, the average being 7.8 mg cadmium per g dry cells. It was also found that 60-70% of cadmium accumulated in cells were distributed in the cell wall fraction.

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Isolation and identification of cellulolytic Actinomycetes (Cellulose 분해 방선균의 분리 및 동정)

  • 정현호;성하진;최용진;양한철
    • Microbiology and Biotechnology Letters
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    • v.14 no.5
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    • pp.377-383
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    • 1986
  • About 300 cellulolytic actinomycetes isolated from soils were tested for their cellulase activities estimated by means of filter paper swelling and carboxymethyl cellulose saccharifying activity. Then, 16 isolates which had shown relatively high levels of CMCase activity were selected and examined for their abilities of $\beta$-glucosidase production. Among them strain No. 109 was found to have highest level of intracellular $\beta$-glucosidase, and selected for the further studies. In this paper, the cultural, morphological and physiological properties, and cell wall composition of strain No. 109 were described in relation to the taxonomic status of this actinomycete. Based on the results obtained in these experiments strain No. 109 was identified to be a similar species to Streptomyces tanashiensis.

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Formation of High-Performance Polymer Walls in a Liquid Crystal Cell by Phase Separation of Fluorinated Polymer Mixture

  • Baek, Jong-In;Shin, Jong-Ba;Oh, Min-Cheol;Kim, Jae-Chang;Yoon, Tae-Boon
    • Journal of Information Display
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    • v.7 no.1
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    • pp.7-11
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    • 2006
  • In this paper, we report the fabrication of high quality polymer walls by using a monomer containing fluorine (F-monomer). Polymer walls with no phase retardation were fabricated by using photo-polymerization induced anisotropic phase separation of the mixture composed of liquid crystal (LC) and F-monomer. Thanks to the immiscibility of fluoride, we could form high quality polymer walls with no light leakage. We measured electro-optic characteristics of a twisted-nematic (TN) LC cell whose polymer walls were fabricated by using the F-monomer, and the measurements were compared with that fabricated by using the monomer without fluorine.

A Study on the Design and Structure of A Microwave Broadband Multi-Section Power Divider (마이크로파대 광대역 다단 전력분배기의 설계방법과 구조에 관한 연구)

  • Park, Jun-Seok;Kim, Hyeong-Seok
    • Proceedings of the KIEE Conference
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    • 2001.07c
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    • pp.1829-1831
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    • 2001
  • A novel multi-section power divider configuration is proposed to obtain wide-band frequency performance up to microwave frequency region. Design procedures for the proposed microwave broadband power divider are composed of a planar multi-section three-ports hybrid and a waveguide transformer design procedures. The multi-section power divider is based on design theory of the optimum quarter-wave transformer. Furthermore, in order to obtain the broadband isolation performance between the two adjacent output ports, the odd mode equivalent circuit should be matched by using the lossy element such as resistor. The derived design formula for calculating these odd mode matching elements is based on the singly terminated filter design theory. The waveguide transformer section is designed to suppress the propagation of the higher order modes such as waveguide modes due to employing the metallic electric wall. Simulation and experiment show excellent performance of multi section power divider.

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Study on Structural-Acoustic Characteristics for Improving Soundproof Qualities to Changeable Wall in Apartment Buildings (공동주택의 건식 가변벽체 접합부 차음성능 향상을 위한 구조음장 특성 해석기법에 관한 연구)

  • Kim, Hwa-Il
    • Journal of Environmental Science International
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    • v.18 no.11
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    • pp.1291-1297
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    • 2009
  • The purpose of this study was to establish structural bone noise analysing method for apartments building floor with Structural-Acoustic coupling analysis. Nowadays, noise through floor is recognized as important problem with the consequence that noise isolation technique is studied in the various fields of industry. From among noise factors, resonance sound is main reason for floor's solid noise. therefore, In this study, evaluation method for composite material slab is established and that a case study is suggested with it.

Measurement and Control of Abnormal Sound for Refrigerator (냉장고의 이상소음에 관한 사례연구)

  • 주재만;김중래;이동현
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2001.05a
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    • pp.380-384
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    • 2001
  • The household reftigerator's noise which is closely related with resident environment can hardly be evaluated its sound quality using the Korean Standards. Radiation characteristics of compressor noise consist of tonal noise in low frequency range and, or narrow band noise in high frequency range. In this study, measuring method for detecting the abnormal and low-level noise in high frequency band is presented, and control method for its reduction is proposed. After installing wall which is similar to living condition, we determined a major concerning frequency band of noise. It can be found the directivity of high frequency noise radiated from compressor by using experiment and analysis. According to isolation of noise transfer path, remarkable noise reduction is achieved.

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