• Title/Summary/Keyword: Microscopic test

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Isolation and Identification of Pseudomonas sp. CMC-50 Producing Carboxymethyl Cellulase and Characterization of Its Crude Enzyme

  • Kim, Hyun-Joong;Kim, Hae-Yeong
    • Journal of Applied Biological Chemistry
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    • v.43 no.2
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    • pp.74-78
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    • 2000
  • A strain that produces a high level of carboxymethyl cellulase was isolated from rotten leaves. The isolated strain was revealed to be gram-negative, oxidase-positive, and catalase-negative. From the electron microscopic features, it was identified as a rod-shaped bacterium with peritrichous flagella and did not form spores. Morphological and biochemical characteristics of the strain were found to be similar to the Pseudomonas species. However, carbon utilization test showed different results. Based on the results, this new strain was identified as Pseudomonas sp. CMC-50. CMCase produced by this strain showed a strong activity in neutral and weak acidic conditions and maximum activity at $50^{\circ}C$.

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Mycologic Characteristics of Trichophyton tonsurans (Trichophyton tonsurans의 진균학적 성상)

  • Bang, Young Jun;Kim, Ssang Young;Shin, Du Man
    • Korean Journal of Clinical Laboratory Science
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    • v.36 no.1
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    • pp.7-12
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    • 2004
  • Trichophyton(T.) tonsurans has been identified for the first time in Korea in 1995 and has been increasing in number of reported in wrestlers, in judo players, and in korean - style wrestlers. Author tried mycological studies with T. tonsurans is isolated in Daegu Korea. The results are as follows: All 16 strains of T. tonsurans tested for nutritional requirement, showed strongly stimulated growth by thiamine, mild to moderate growth on casamino acid agar, poor growth on ammonium nitrates base agar. All 16 strains of T. tonsurans tested showed positive results for hair perforation and urease test. Gross findings of T. tonsurans showed that fine granular surface with light yellow hue or white color and mahogany brown color on the reverse side. Microscopic findings showed that septated hyphae, chlamydoconidia and microcondia. Microconidia were characteristic in their arrangerment and shape : round or oval shaped microconidia laterally to hyphae, some were match - head like terminal swelling.

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Application of Optical Method for Quantitative Investigation of MgO Erosion in AC-PDP

  • Choi, Seung-Ho;Lee, Soon-Il;Oh, Soo-Ghee;SunWoo, Jin-Ho;Kim, Jae-Gak;Lee, Gol-Hee;Kim, June-Dong
    • 한국정보디스플레이학회:학술대회논문집
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    • 2000.01a
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    • pp.185-186
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    • 2000
  • For the quantitative investigation of the erosion of MgO layers in real ac-PDP cells, we constructed a microscopic spectrophotometer which is capable of measuring transmission spectra from the area as small as 20 ${\times}$ 20 ${\mu}m^2$. In the test on the sputtered MgO films with a thickness gradient, we were able to probe the thickness variation of 1000 nm over $1000-{\mu}m$ distance. Using this instrument, we were able to determine not only the erosion rate at the particular position of ac-PDP cells but also the relative erosion rate at different positions in a single ac-PDP cell.

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Evaluation and monitoring of degradation mechanism of Li-ion battery for portable electronic device (휴대전자기기용 저용량 리튬이온 배터리의 충방전 열화 기구 분석 및 모니터링)

  • Byeon, Jai Won
    • Journal of Applied Reliability
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    • v.13 no.2
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    • pp.129-140
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    • 2013
  • As a fundamental experimental study for reliability improvement of lithium ion secondary battery, degradation mechanism was investigated by microscopic observation and acoustic emission monitoring. Microstructural observation of the decomposed battery after cycle test revealed mechanical and chemical damages such as interface delamination, microcrack of the electrodes, and solid electrolyte interphase (SEI). Acoustic emission (AE) signal was detected during charge and discharge of lithium ion battery to investigate relationships among cumulative count, discharge capacity, and microdamages. With increasing number of cycle, discharge capacity was decreased and AE cumulative count was observed to increase. Observed damages were attributed to sources of the detected AE signals.

A post-peak analysis of concrete structures using a 9-node assumed strain shell element (9절점 가변형도 쉘요소를 이용한 콘크리트 구조물의 후-정점하중 해석)

  • 이상진;이홍표;서정문
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2001.10a
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    • pp.59-66
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    • 2001
  • The post-peak analysis of concrete structures is carried out using a nine-node Reissner-Mindlin(RM) shell element which is formulated by using degenerated solid concepts. In order to avoid element deficiencies inherited in the standard RM shell element, assumed strains are adopted in the present shell element. A microscopic material model is adopted to represent the inelastic characteristic of concrete material. In particular, a concrete softening model is introduced to this material model. The arc-length control method is used to trace the post-peak behaviour of concrete structures. From the numerical test of the single-edge-notched beam, the present shell element shows a reasonable agreement with experimental data.

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A New PIM Joining Process

  • Miura, Hideshi
    • Journal of Powder Materials
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    • v.9 no.4
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    • pp.203-210
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    • 2002
  • A new PIM in-process joining technique has been developed for more complicated and functional PIM components by application of the exuded wax from the green compacts during solvent debinding step. At first, various stainless steels and iron compacts with rectangular shape were combined, and the joining behaviors and properties were investigated by shear and tensile test, and microscopic observation. Subsequently, perfect joined three pieces of thin and hollow compacts were obtained for the combination of same and different stainless steels, and it was difficult to join the iron and stainless steel compacts in hydrogen atmosphere because of the different starting temperature of shrinkage. However, pretty good joined iron and stainless steel compacts were obtained by consideration of particle size and vacuum atmosphere. Finally, for the combination of ferro-silicon and austenitic stainless steel compacts, high functionality (magnetic (1.60Tes1a) & non-magnetic) and perfect joint were obtained.

Analysis of Anisotropic Structures under Multiphysics Environment (멀티피직스 환경하의 이방성 구조물 해석)

  • Kim, Jun-Sik;Lee, Jae-Hun;Park, Jun-Young
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.10 no.6
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    • pp.140-145
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    • 2011
  • An anisotropic beam model is proposed by employing an asymptotic expansion method for thermo-mechanical multiphysics environment. An asymptotic method based on virtual work is introduced first, and then the variables of mechanical displacement and temperature rise are asymptotically expanded by taking advantage of geometrical slenderness of elastic bodies. Subsequently substituting these expansions into the virtual work principle allows us to asymptotically expand the virtual work. This will yield a set of recursive virtual works from which two-dimensional microscopic and one-dimensional macroscopic equations are systematically derived at each order. In this way, homogenized stiffnesses and thermomechanical coupling coefficients are derived. To demonstrate the validity and efficiency of the proposed approach, composite beams are taken as a test-bed example. The results obtained herein are compared to those of three-dimensional finite element analysis.

Reliability Improvement Method of Weld Zone in Water Wall Tube for an Ultra Supercritical Coal Fired Boiler (초초임계압 석탄화력 보일러 수냉벽 수관의 용접신뢰성 향상방안)

  • Ahn, Jong-Seok;Moon, Seung-Jae
    • Plant Journal
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    • v.6 no.3
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    • pp.53-61
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    • 2010
  • This paper presents failure analysis on weld-joint of the waterwall tubes in USC boilers. Visual inspections were performed to find out the characteristics of the fracture. Additionally both microscopic characteristics and hardness test were carried out on failed tube samples. Failures seem to happen mainly because the welding process such as preheating and PWHT(post-weld heat treatment) was not conducted strictly. Thus, this paper has the purpose to describe the main cause of the poor welding process and to explain how to prevent similar failures in those weld-joints.

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Computer Vision System for Analysis of Geometrical Characteristics of Agricultural Products and Microscopic Particles (I) -Algorithms for Automatic Threshold Selection- (농산물 및 미립자의 기하학적 특성 분석을 위한 컴퓨터 시각 시스템(I) -자동(自動) 문턱값 설정(設定) 알고리즘-)

  • Lee, J.W.;Noh, S.H.
    • Journal of Biosystems Engineering
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    • v.17 no.2
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    • pp.132-142
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    • 1992
  • The main objective of this paper is to evaluate and modify the existing algorithms for the automatic threshold selection. Four existing algorithms were evaluated quantitatively using test images of coffee droplets and an apple. The images had the different area ratio of the object to the image size, different average gray values between the object and the background, and different S/N ratio of the Gaussian noise. The result showed that Histogram Clustering Method and Maximum Entropy Method were better than Moment Preserving Method and Simple Image Statistic Method in automatic thresholding.

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A Study on Headway Distribution Models of Rural Two Lane Roads (지방부 2차로도로의 차두시간 분포 모델에 관한 연구)

  • Moon, Jaepil;Kim, Dongnyong
    • International Journal of Highway Engineering
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    • v.16 no.1
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    • pp.49-56
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    • 2014
  • PURPOSES : This study was done to model the headway distribution of rural two lane roads. METHODS : Time headway data for the various level of traffic volumes was measured in twelve sites. Based on the time headway data, existing seven mathematical models were evaluated and selected by comparing graphically the measured and theoretical distributions and conducting the Chi-square test. RESULTS : The results show that both the Schul model and Composite Model were the most appropriate models of the models. Based on the measured time-headway distributions, this study proposed a new headway distribution model by the shift of the Schul model. CONCLUSIONS : The shifted Schul model has the ability to describe time headway distirbutons for random, intermediate, and constant-headway states.