• Title/Summary/Keyword: Additional strain

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Isolation and Characterization of Pseudomonas sp. DCB3 Degrading 1.2-Dichlorobenzene (1.2-Dichlorobenzene을 분해하는 Pseudomonas sp. DCB3의 분리 및 특성)

  • 서승교;우철주;이창호
    • Journal of Environmental Health Sciences
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    • v.23 no.4
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    • pp.33-38
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    • 1997
  • Four bacterial strains able to degrade dichlorobenzene as the sole source of carbon and energy were isolated from soil by selective enrichment culture, and among them, one isolation was the best in the cell growth and identified as Pseudomonas sp. DCB3 by its morphology and physiological properties. Cell growth dramatically increased in a minimal medium containing 500ppm of dichlorobenzene was not detected any more at 72 hours after cultivation. The optimal temperature and initial pH for the growth of the isolated strain were 30$\circ$C and 7.0, respectively. Cell growth was increased by supplementing $(NH_2)_2CO$ and 50 ppm yeast extract as additional nutrients. Therefore, it was suggested that Pseudomonas sp. DCB3 could be effectively used for the biological treatment of wastewater containing dichlorobenzene.

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Effects of Monosaccharides and Disaccharides on the Rheological Behavior of Dense Alumina Slurries I. Creep Testing Method

  • Kim, Jong-Cheol;Auh, Keun-Ho;Chr
    • The Korean Journal of Ceramics
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    • v.5 no.2
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    • pp.104-109
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    • 1999
  • Rheological properties of dense slurries over 45 volume % with different monosaccharides and disaccharides were checked in order to increase the solid content of dense slurries without sacrificing plasticity using creep testing method. Strain in creep test showed good correlations with Burger model which is expressed as an exponential function of time. Among several monosaccharides and disaccharides studied here, fructose and sucrose were most effective in making dense alumina slurry plastic than other monosaccharides and disaccharides like glucose, galactose, xyloss and maltose. In the case of dense alumina slurry with sucrose, sucrose content or additional water content enhanced to the plasticity of the slurries.

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Experimental and numerical studies on seismic behaviour of exterior beam-column joints

  • Asha, P.;Sundararajan, R.
    • Computers and Concrete
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    • v.13 no.2
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    • pp.221-234
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    • 2014
  • A nonlinear finite element analysis using ANSYS is used to evaluate the seismic behavior of reinforced concrete exterior beam-column joints. The behavior of the finite element models under cyclic loading is compared with the experimental results. Two beam-column joint specimens (SH and SHD) with square hoop confinement in joint and throughout the column with detailing as per IS 13920 are studied. The specimen SHD was provided with additional diagonal bars from column to beam to relocate the plastic hinge formation from beam-column interface. The load-displacement relationship, joint shear stress and strain in beam obtained from numerical study showed good agreement with the experimental results. This investigation proves that seismic behaviour of reinforced concrete beam-column joints under reversed cyclic loading can be evaluated successfully using finite element modeling and analysis.

Phase Identification of Nano-Phase Materials using Convergent Beam Electron Diffraction (CBED) Technique

  • Kim, Gyeung-Ho;Ahn, Jae-Pyoung
    • Applied Microscopy
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    • v.36 no.spc1
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    • pp.47-56
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    • 2006
  • Improvements are made to existing primitive cell volume measurement method to provide a real-time analysis capability for the phase analysis of nanocrystalline materials. Simplification is introduced in the primitive cell volume calculation leading to fast and reliable method for nano-phase identification and is applied to the phase analysis of Mo-Si-N nanocoating layer. In addition, comparison is made between real-time and film measurements for their accuracy of calculated primitive cell volume values and factors governing the accuracy of the method are determined. About 5% accuracy in primitive cell determination is obtained from camera length calibration and this technique is used to investigate the cell volume variation in WC-TiC core-shell microstructure. In addition to chemical compositional variation in core-shell type structure, primitive cell volume variation reveals additional information on lattice coherency strain across the interface.

A Study on Application and Validation of the Coherent Flamelet Model in Counterflow Turbulent Premixed Combustion (대향류 예혼합 난류 연소 유동에서의 Coherent Flamelet Model 적용 및 검증에 관한 연구)

  • Choi, C.R.;Huh, K.Y.
    • Journal of the Korean Society of Combustion
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    • v.1 no.2
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    • pp.51-58
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    • 1996
  • The coherent flamelet model(CFM) is applied to symmetric counterflow turbulent premixed flames. The flame source term is set proportional to the turbulence intensity to reproduce the experimental correlation of Abdel-Gayed et al. for the turbulent burning velocity. Flame quenching by the turbulent rate of strain is modeled by an additional multiplication factor to the flame source term. A modified form of CFM is employed to consider coexistence of burned and unburned premixture with ambient air. The predicted flame position and turbulent flow field coincide well with the experimental data of Kostiuk et al., although there is some discrepancy in the radial rms velocity component and integral length scale near the symmetric plane.

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Ion-Implanted Drift Field Silicon Solar Cell

  • Lee, Hee-Yong;Kim, Jin-Kon;Kim, Yoo-Shin
    • Nuclear Engineering and Technology
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    • v.8 no.1
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    • pp.29-40
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    • 1976
  • An investigation on the effect of electrostatic drift field which can bring an additional aid to the photogenerated carrier collection in one side of the silicon solar cell has been carried out. The drift field was produced by the gradient of boron concentration in the p-type side in virtue of the strain compensation due to the tin dopant. A new method of ion implantation which is based on the principle of chiefly radiation-enhanced diffusion is adopted for forming the p-n junction in the solar cell. The open circuit voltage and the conversion efficiency of the ion-implanted silicon solar cell sample can be figured out to be 0.44 V and 5%, respectively.

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Plasticity of Amorphous Alloys: 2. Inhomogeneous Deformation (비정질 합금의 소성 2: 불균일변형)

  • Park, Kyoung-Won;Lee, Chang-Myeon;Lee, Jae-Chul
    • Korean Journal of Metals and Materials
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    • v.47 no.11
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    • pp.773-785
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    • 2009
  • Studies of a number of Cu-Zr amorphous alloys have demonstrated that those exhibiting greater plastic strain during homogeneous deformation at room temperature show lower global plasticity associated with inhomogeneous deformation in a typical compression test. Using a combination of experiments and molecular dynamics simulations, we clarify this seeming paradox between the homogeneous and inhomogeneous deformation by exploring the microstructural aspects in view of the structural disordering, disorder-induced softening, and shear localization and relate these findings to the global plasticity of bulk amorphous alloys. Additional analyses were conducted to derive a simple structural parameter that allows the prediction of the global plasticity of bulk amorphous alloys.

Estimation of Residual Stress in ReBCO Coated Conductor Tapes Using Various Methods

  • Dizon, John Ryan C.;Shin, Hyung-Seop;Ko, Rock-Kil;Ha, Dong-Woo;Oh, Sang-Soo
    • Progress in Superconductivity and Cryogenics
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    • v.10 no.4
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    • pp.9-12
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    • 2008
  • The residual stress induced in the superconducting layer was estimated using analytical approach coupled with electro-mechanical test results and XRD measurements. The residual stress measured based on the $I_{c}/I_{c0}$-strain degradation behavior showed similar value with the measured residual stress using XRD. The calculated residual stress based on the thermal analysis showed the lowest value. This could be explained by the additional intrinsic residual stresses induced in the superconducting film during deposition.

Stability of an improved optimization iterative algorithm to study vibrations of the multi-scale solar cells subjected to wind excitation using Series-Fourier algorithm

  • Jing Pan;Yi Hu;Guanghua Zhang
    • Steel and Composite Structures
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    • v.50 no.1
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    • pp.45-61
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    • 2024
  • This research explores the domain of organic solar cells, a photovoltaic technology employing organic electronics, which encompasses small organic molecules and conductive polymers for efficient light absorption and charge transport, leading to electricity generation from sunlight. A computer simulation is employed to scrutinize resonance and dynamic stability in OSCs, with a focus on size effects introduced by nonlocal strain gradient theory, incorporating additional terms in the governing equations related to displacement and time. Initially, the Navier method serves as an analytical solver to delve into the dynamics of design points. The accuracy of this initial step is verified through a meticulous comparison with high-quality literature. The findings underscore the substantial impact of viscoelastic foundations, size-dependent parameters, and geometric factors on the stability and dynamic deflection of OSCs, with a noteworthy emphasis on the amplified influence of size-dependent parameters in higher values of the different layers' thicknesses.

Crystal Structure and Physical Property of Tetragonal-like Epitaxial Bismuth Ferrites Film

  • Nam, Joong-Hee;Biegalski, Michael;Christen, Hans M.;Kim, Byung-Ik
    • Proceedings of the Korean Magnestics Society Conference
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    • 2011.06a
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    • pp.7-8
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    • 2011
  • Basically, the lattice mismatch between film and substrate can make those BiFeO3(BFO) films distorted with strain structure. BFO phase can be stabilized on LaAlO3(LAO) represents the example of a multiferroic with giant axial ratio. Its crystal structure is not strictly tetragonal, but tetragonal with a slight monoclinic distortion and related to the rotation of the oxygen octahedra. In this study, we show that phases with a tetragonal-like epitaxial BFO films can indeed be ferroelectric and also can be stabilized via epitaxial growth onto LAO. Recent reports on epitaxial BFO films show that the crystal structure changes from nearly rhombohedral ("R-like") to nearly tetragonal("T-like") at strains exceeding approximately -4.5%, with the "T-like" structure being characterized by a highly enhanced c/a ratio. While both the "R-like" and the "T-like" phases are monoclinic, our detailed x-ray diffraction results reveal asymmetry change from MA and MC type, respectively. By applying additional strain or by modifying the unit cell volume of the film by substituting Ba for Bi, the monoclinic distortion in the "T-like" MC phase is reduced, i.e. the system approaches a true tetragonal symmetry. There are two different M-H loops for $Bi_{1-x}Ba_xFeO_{3-{\delta}}$(BBFO) and BFO films on SrTiO3(STO) & LAO substrates. Along with the ferroelectric characterization, these magnetic data indicate that the BFO phase stabilized on LAO represents the first example of a multiferroic with giant axial ratio. However, there is a significant difference between this phase and other predicted ferroelectrics with a giant axial ratio: its crystal structure is not strictly tetragonal, but tetragonal with a slight monoclinic distortion. Therefore, in going from bulk to highly-strained films, a phase sequence of rhombohedral(R)-to-monoclinic ["R-like" MA-to-monoclinic, "T-like" MC-to-tetragonal (T)] is observed. This sequence is otherwise seen only near morphotropic phase boundaries in lead-based solid-solution perovskites (i.e. near a compositionally induced phase instability), where it can be controlled by electric field, temperature, or composition. Our results show that this evolution can occur in a lead-free, stoichiometric material and can be induced by stress alone. Those major results are summarized as follows ; 1) Ba-doping increases the unit cell volume, 2) BBFO on LAO can be fully strained up to x=0.08 as a strain limit (Fig. 1), 3) P(E) & M(H) properties can be tuned by the variation of composition, strain, and film thickness.

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