• 제목/요약/키워드: G597

검색결과 115건 처리시간 0.02초

Bacillus stearothermophilus 가 생산하는 Xylanase의 정제 및 특성 (Purification and Characterization of an Extracellular Xylanase of Bacillus stearothermophilus)

  • 배성호;최용진
    • 한국미생물·생명공학회지
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    • 제19권6호
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    • pp.592-597
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    • 1991
  • 토양 분리균인 B.stearothermophilus가 생산하는 xylanase를 ammonium sulfate 분획, DEAE-Sepharose CL-6B ion exchange chromatography, Sephadex G-100 gel 여과 및 열처리 등의 과정을 거쳐 단일 단배질로 분리 정제하였다. 170,000의 분자량을 본 정제 xylanase는 pH8과 pH10 사이의 넓은 최적 pH를 보였으며 $55^{\circ}C$에서 최대 활성을 나타내었다. $55^{\circ}C$에서 2시간의 열처리에 의해서도 활서의 손실이 거의 없을 정도로 열에 매우 안정하였으며 $co^{2+}$$Mn^{2+}$에 의해서 현저한 활성화 효과를 보였다.

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액체크로마토그래프/질량분석기를 이용한 수중 남조독소물질 동시분석법 (Method for Simultaneous Determination of Cyanotoxins in Water by LC-MS/MS)

  • 김정희;윤미애;김학철
    • 한국물환경학회지
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    • 제25권4호
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    • pp.597-605
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    • 2009
  • Algae bloom occurred in reservoir in summer can cause taste and odor in water and disturb the flocculation and sedimentation processes in water treatment plant and cause sand filter plugging. It was also reported that microcystins, anatoxin and saxitoxin released from cyanobacteria had acute toxic effects on liver and nervous system. For these reasons, many advanced countries inclusive of WHO set the guideline for these toxins and cyanotoxins have been managed with regular monitoring in Korea as well. However, complex sample preparation steps such as a solid phase extraction (SPE) and derivatization are required with an existing analysis method with HPLC. We needed to improve an analysis method for low extraction efficiency and long sample preparation time. In this study, we have established a new LC/MS/MS method which can simultaneously determine 6 cyanotoxins (Microcystins-LR, Microcystins-RR, Microcystins-YR, Anatoxin-a, Saxitoxin, Neosaxitoxin) with only simple filtration step. When $75{\mu}L$ filterated sample was injected onto the LC-MS/MS, the recovery ranged from 86% to 112% and the MDL was $0.025{\sim}0.581{\mu}g/L$. We can make the MDL be lower than the guideline ($1{\sim}3{\mu}g/L$) of advanced countries with simple preparation.

Forming Low-Resistivity Electrodes of Thin Film Transistors with Selective Electroless Plating Process

  • Chiang, Shin-Chuan;Chuang, Bor-Chuan;Tsai, Chia-Hao;Chang, Shih-Chieh;Hsiao, Ming-Nan;Huang, Yuan-Pin;Huang, Chih-Ya
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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    • pp.597-600
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    • 2006
  • The silver gate and source/drain electrodes for an a-Si thin film transistor were fabricated by the selective electroless plating (SELP) process. Relevant physical properties including taper angle, uniformity and resistivity are investigated. The Ag layer was about 150nm to 250nm thick, the resistivity less than $3{\times}10^{-6}$ Ohm-cm and the taper angle 45'-60' and the nonuniformity less than 10% on G2 substrates. The transfer characteristics with the Ag gate, and source/drain electrodes respectively possessed good field effect mobility similar to conventionally fabricated a-Si TFTs. This process provided low resistivity, low cost and ease of processing.

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Free Energy of Formation of BaThO3 from E.M.F. Measurement

  • Park, S. H.;H. D. Baek;J. S. Hwang;Park, C. O.
    • The Korean Journal of Ceramics
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    • 제4권3호
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    • pp.204-206
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    • 1998
  • The Gibbs free energy of formation of $BaThO_3$ from elemental oxides has been measured at temperatures between 853 and 903 K using a $CaF_2$ solid electrolyte galvanic cell. The galvanic cell consisted of Pt, $O_2, CaO+CaF_2 \parallel CaF_2 \parallelBaThO_3+ThO_2+BaF_2, O_2$, Pt EMF gave the standard Gibbs free energy for the reaction $CaF_2+BaThO_3=CaO+BaF_2+ThO_3$ as $\DeltaG^o$,/TEX>=124111.031-117.597 T(J/mol).

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Sinusoidal Model을 이용한 Cochannel상에서의 음성분리에 관한 연구 (A Study on Speech Separation in Cochannel using Sinusoidal Model)

  • 박현규;신중인;박상희
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1997년도 추계학술대회 논문집 학회본부
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    • pp.597-599
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    • 1997
  • Cochannel speaker separation is employed when speech from two talkers has been summed into one signal and it is desirable to recover one or both of the speech signals from the composite signal. Cochannel speech occurs in many common situations such as when two AM signals containing speech are transmitted on the same frequency or when two people are speaking simultaneously (e. g., when talking on the telephone). In this paper, the method that separated the speech in such a situation is proposed. Especially, only the voiced sound of few sound states is separated. And the similarity of the signals by the cross correlation between the signals for exactness of original signal and separated signal is proved.

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유체-구조물 상호작용을 위한 유한요소 결합공식화의 예조건화에 대한 연구 (Study on the preconditioning method of a finite element combined formulation for fluid-structure interaction)

  • 최형권
    • 한국전산유체공학회:학술대회논문집
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    • 한국전산유체공학회 2008년도 춘계학술대회논문집
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    • pp.597-600
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    • 2008
  • Preconditioners for a two-dimensional combined finite element formulation have been devised and tested for fluid-structure interaction (FSI) problems. The FSI code simulating the interaction of a elastic body with an unsteady flow is based on P2P1 finite element combined formulation. It has been shown that two preconditioners among them perform well with respect to computational memory and convergence for a bench-mark problem. Based on the verification of the preconditioners for the two-dimensional combined formulation, four preconditioners are proposed for the problem of an elastic body interacting with a flow.

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ETSI의 표준화 작업방법 분석 (Bake-off를 중심으로) (Analysis on the Bake-off service in ETSI)

  • 박종봉;김영태
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2001년도 춘계종합학술대회
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    • pp.597-600
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    • 2001
  • ETSI는 1988년 3원에 설립된 이래 GSM과 같은 이동통신 표준화분야에서 강력한 위치를 차지하고 있다. 이는 ETSI가 외부환경을 끊임없이 주시하고 이를 대처할 수 있는 유연한 조직과 다양한 표준화 작업방법을 구축하고 있기 때문이다. 본 논문에서는 ETSI의 작업방법 중 표준개발 주기의 단축과 고품질의 표준개발을 위해 도입된 Bake-off를 상세 분석하고자 한다.

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Sclerotirum cepivorum에 대한 마늘 재배종의 저항성 검정 (Screening for Resistance of Garlic Cultivars to White Rot Caused by Sclerotium cepivorum)

  • 이용훈;이왕휴;이두구
    • 한국식물병리학회지
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    • 제14권6호
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    • pp.594-597
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    • 1998
  • The optimal quantity of inoculum was determined to screen resistance of garlic cultivars against Sclerotium cepivorum and 30 cultivars was tested. The growth of the pathogen in detached roots, Disease incidence was increased when the inoculum density was raised form 10 to 100 sclerotia. The optimal inoculum density to differentiate resistance or susceptibility of garlic cultivars was seemed to be 50 sclerotia. The cultivars collected from England, Japan, Nepal and Turkey, and cultivars such as common red, PI1356104 and PI135693 were less than the other cultivars in their disease incidence. The growth of S. cepivorum in detached roots varied from 23 to 33 mm according to garlic cultivars. There was no relationship between the disease incidence and the growth in detached roots. The sclerotial germination was increased significantly when root extract was extract was added. The addition of only distilled water resulted in 13% germination, but the addition of 0.25 g of root extract in 100 ml distilled water resulted in more than 85% germination. There was no difference in the stimulation of sclerotial germination among cultivars which showed different resistance.

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흰쥐 조직에서의 카드뮴 결합 고분자량 단백질 [Cd-BP(II)]의 유도 (Induction of Cd-binding High Molecular Weight Protein [Cd-BP(II)] in Rat Tissues)

  • 천기정;김봉희
    • 약학회지
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    • 제43권5호
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    • pp.591-597
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    • 1999
  • The study was carried out on the biochemical characters of Cd-BP(II) after isolation and purification of the protein from the liver of rat ip injection with Cd. A continued study has been doing whether Cd-BP(II) could be induced by Cd or by the other metals such as Zn and Cu. Antisera were made against the antigen of Cd-BP(II) from New Zealand white rabbits. We carried out g-globulin purification, then Ouchterlony test and gel immunodiffusion test. Cd-BP(II) was also found in normal tissues of rat. It was induced up to a considerable level by Cd, whose induced level was higher than that Cu or Zn treatment. The level of induction by Cu or Zn pretreatment plus Cd treatment was lower than that by single treatment of Cu or Zn. Such a result was presumably related to the Cd toxicity.

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Topology optimization of variable thickness Reissner-Mindlin plate using multiple in-plane bi-directional functionally graded materials

  • Nam G. Luu;Thanh T. Banh;Dongkyu Lee
    • Steel and Composite Structures
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    • 제48권5호
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    • pp.583-597
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    • 2023
  • This paper introduces a novel approach to multi-material topology optimization (MTO) targeting in-plane bi-directional functionally graded (IBFG) non-uniform thickness Reissner-Mindlin plates, employing an alternative active phase approach. The mathematical formulation integrates a first shear deformation theory (FSDT) to address compliance minimization as the objective function. Through an alternating active-phase algorithm in conjunction with the block Gauss-Seidel method, the study transforms a multi-phase topology optimization challenge with multi-volume fraction constraints into multiple binary phase sub-problems, each with a single volume fraction constraint. The investigation focuses on IBFG materials that incorporate adequate local bulk and shear moduli to enhance the precision of material interactions. Furthermore, the well-established mixed interpolation of tensorial components 4-node elements (MITC4) is harnessed to tackle shear-locking issues inherent in thin plate models. The study meticulously presents detailed mathematical formulations for IBFG plates in the MTO framework, underscored by numerous numerical examples demonstrating the method's efficiency and reliability.