• Title/Summary/Keyword: Phase identification

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Synthesis and comparison of pure TiO2 and metal/non-metal doped TiO2 as a photocatalyst

  • Moon, Jiyeon;Lee, Kyusang;Kim, Seonmin
    • Proceedings of the Korean Vacuum Society Conference
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    • 2016.02a
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    • pp.370.1-370.1
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    • 2016
  • Volatile organic compounds (VOCs) are considered hazardous air pollutants and these are emitted from building materials and household products. VOCs can cause global warming as well as human sickness, and even cancer. Photocatalysis provides a way of converting VOCs into harmless materials. Various researches have shown that $TiO_2$ is the most efficient photocatalysts due to its excellent activity. In this study, metal/non-metal doped $TiO_2$ particles are synthesized for the enhancement of the photocatalytic properties of pure $TiO_2$. By metal/non-metal doping, band gap energies of prepared samples were analyzed by UV/Visible spectrophotometer. The physical and chemical properties of synthesized powder were characterized by field emission scanning electron microscope, by BET for measuring their specific surface area, and by XRD for phase identification and particle size determination. Degradation ability for p-xylene was evaluated through monitoring the concentration in a closed chamber. Relation between their properties and decomposition abilities for VOC were evaluated based on the experimental results.

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Induction Machine Fault Detection Using Generalized Feed Forward Neural Network

  • Ghate, V.N.;Dudul, S.V.
    • Journal of Electrical Engineering and Technology
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    • v.4 no.3
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    • pp.389-395
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    • 2009
  • Industrial motors are subject to incipient faults which, if undetected, can lead to motor failure. The necessity of incipient fault detection can be justified by safety and economical reasons. The technology of artificial neural networks has been successfully used to solve the motor incipient fault detection problem. This paper develops inexpensive, reliable, and noninvasive NN based incipient fault detection scheme for small and medium sized induction motors. Detailed design procedure for achieving the optimal NN model and Principal Component Analysis for dimensionality reduction is proposed. Overall thirteen statistical parameters are used as feature space to achieve the desired classification. GFFD NN model is designed and verified for optimal performance in fault identification on experimental data set of custom designed 2 HP, three phase 50 Hz induction motor.

Identification of csp Homolog in Bradyrhizobium japonicum

  • No, Jae-Sang;Yu, Ji-Cheol;So, Jae-Seong
    • 한국생물공학회:학술대회논문집
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    • 2001.11a
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    • pp.602-605
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    • 2001
  • Low-temperature adaptation and protection for environmental stresses were studied in the gram-negative soil bacterium Bradyrhizobium japonicum 61A101c. B. japonicum was more resistant to alcohol, $H_2O_2$, heat and freezing following a pretreatment at $4^{\circ}C$, resulting in approximately 10 to 1,000 folds increased survival compared to mid-exponential-phase cells grown at an optimal temperature at $28^{\circ}C$. This phenomena relate to the cold shock protein expressed when cells are exposed to a downshift in temperature. To confirm the presence of cold shock protein genes in B. japonicum, a PCR strategy was employed using a degenerate primer set, which successfully amplified a putative csp gene fragment. Sequence analysis of the PCR product(200bp) revealed csp-like sequences that were up to 96% identical to csp gene of S. typhimurium.

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Premature Stiffening of Cement Paste Associated with AFm Formation

  • Chung, Chul-Woo;Lee, Jae-Yong
    • Journal of the Korea Institute of Building Construction
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    • v.11 no.1
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    • pp.83-90
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    • 2011
  • The purpose of this research is to investigate the effect of AFm formation on the stiffening process of cement paste. High and low alkali sulfate clinkers were used for the experiments. The flow and stiffening behavior of cement paste was investigated using modified ASTM C403 penetration resistance test and oscillatory shear rheology. X-ray powder diffraction (XRD) was used for phase identification associated with stiffening of the paste. It was found from the results that low alkali clinker mixture produced very strong premature stiffening whereas high alkali clinker mixture did not cause premature stiffening. This is because of the large amount of alkali sulfate present in the clinker. Addition of calcium and sodium chloride to the high alkali clinker mixture caused faster stiffening and set.

Cancer Metabolism: Strategic Diversion from Targeting Cancer Drivers to Targeting Cancer Suppliers

  • Kim, Soo-Youl
    • Biomolecules & Therapeutics
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    • v.23 no.2
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    • pp.99-109
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    • 2015
  • Drug development groups are close to discovering another pot of gold-a therapeutic target-similar to the success of imatinib (Gleevec) in the field of cancer biology. Modern molecular biology has improved cancer therapy through the identification of more pharmaceutically viable targets, and yet major problems and risks associated with late-phase cancer therapy remain. Presently, a growing number of reports have initiated a discussion about the benefits of metabolic regulation in cancers. The Warburg effect, a great discovery approximately 70 years ago, addresses the "universality" of cancer characteristics. For instance, most cancer cells prefer aerobic glycolysis instead of mitochondrial respiration. Recently, cancer metabolism has been explained not only by metabolites but also through modern molecular and chemical biological techniques. Scientists are seeking context-dependent universality among cancer types according to metabolic and enzymatic pathway signatures. This review presents current cancer metabolism studies and discusses future directions in cancer therapy targeting bio-energetics, bio-anabolism, and autophagy, emphasizing the important contribution of cancer metabolism in cancer therapy.

Identification of Reflection Coefficients for Overground Pipes Using Finite Element Method (유한요소법을 이용한 지상 파이프 반사계수 규명)

  • Kim, Y.W.;Park, K.J.;Kang, W.S.
    • Journal of Power System Engineering
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    • v.15 no.3
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    • pp.18-24
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    • 2011
  • In this study, the reflection of the L(0,2), axially symmetric guided elastic wave from defects in pipes above ground is examined using finite element method. Phase and group velocity dispersion curves for the pipe were presented for the selection of the excitation mode. Some simple signal processing was applied to determine the amplitude of each of the reflected waves and to calculate the reflection coefficient. The results show the reflection coefficient of this mode is very close to a linear function of the circumferential extent of the defect. The motivation for the work was the development of a technique for inspecting chemical plant pipelines, but the study addresses the nature of the reflection function and its general applicability.

Nitrosative protein tyrosine modifications: biochemistry and functional significance

  • Yeo, Woon-Seok;Lee, Soo-Jae;Lee, Jung-Rok;Kim, Kwang-Pyo
    • BMB Reports
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    • v.41 no.3
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    • pp.194-203
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    • 2008
  • Nitrosative modifications regulate cellular signal transduction and pathogenesis of inflammatory responses and neuro-degenerative diseases. Protein tyrosine nitration is a biomarker of oxidative stress and also influences protein structure and function. Recent advances in mass spectrometry have made it possible to identify modified proteins and specific modified amino acid residues. For analysis of nitrated peptides with low yields or only a subset of peptides, affinity 'tags' can be bait for 'fishing out' target analytes from complex mixtures. These tagged peptides are then extracted to a solid phase, followed by mass analysis. In this review, we focus on protein tyrosine modifications caused by nitrosative stresses and proteomic methods for selective enrichment and identification of nitrosative protein modifications.

Genetic Algorithm for Designing Independent Manufacturing Cells (독립적인 생산셀 설계를 위한 유전 알고리즘)

  • Moon, Chi-Ung;Yi, Sang-Yong
    • Journal of Korean Institute of Industrial Engineers
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    • v.23 no.3
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    • pp.581-595
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    • 1997
  • The procedure of grouping the machines and parts to form cells is called manufacturing cell design. The manufacturing cell design is an important step in the development and implementation of advanced manufacturing systems. For the successful implementation of the manufacturing systems, identification of independent manufacturing cells, i.e., cells where parts are completely processed in the cell and no intercell movements, is necessary in the design phase. In this paper, we developed a mixed integer programming model and genetic algorithm based procedure to solve the independent manufacturing cells design problem considering the alternative process plans and machines duplication. Several manufacturing parameters such as, production volume, machine capacity, processing time, number of cells and cell size, are considered in the process. The model determines the process plan for parts, port families and machine cells simultaneously. The model has been verified with the numerical examples.

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Identification and Quantitative Analysis of Flavonol Glycosides from Ginkgo biloba Leaves by High Performance Liquid Chromatography (고속액체크로마토그라피에 의한 은행잎중 Flavonoid Glycoside의 확인 및 정량)

  • Kang, Sam-Sik;Kim, Ju-Sun;Kwak, Wie-Jong;Kim, Ki-Hyup
    • Korean Journal of Pharmacognosy
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    • v.21 no.2
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    • pp.148-152
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    • 1990
  • Seven flavonol glycosides from the EtOAc fraction of Ginkgo biloba leaves were identified by high performance liquid chromatography. Separation by reversed phase chromatography on $Lichrosorb^{\circledR}$ RP-18 column was achieved by isocratic elution. The content of the major acylated flavonol glycoside, kaempferol 3-0-[$6'-O-{p}-coumaroyl-{\beta}-_D-glucosyl(1{\rightarrow}2)-{\alpha}-_L-rhamnoside$] was about 8.0% and 0.55% for EtOAc fraction and MeOH extract, respectively.

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Phase equilibria and structure identification of tert-butylhydroperoxide + gaseous clathrate hydrates (이성분계(3차 부틸-히드로과산화물 + 기체) 클러스레이트 하이드레이트의 구조적 특성과 열역학적 안정성에 관한 연구)

  • Youn, Yeobeom;Cha, Minjun;Kwon, Minchul;Lee, Huen
    • 한국신재생에너지학회:학술대회논문집
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    • 2011.05a
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    • pp.150.1-150.1
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    • 2011
  • Structure-II hydrate has been highlighted due to its higher gas storage capacity and favorable thermodynamic conditions. In this study, we introduce a new structure-II hydrate former, tert-butyl hydroperoxide (TBHP) and confirm the structural characteristics through High-Resolution Powder Diffraction (HRPD), $^{13}C$ solide-state NMR and Ramanspectroscopy. Here,we also investigated the thermodynamic stability of binary(TBHP+gaseous) clathrate hydrates. The experimental data were generated using an isochoric pressure-search method. The dissociation data for (TBHP +gaseous) clathrate hydrates are compared with the other hydrocarbon hydrate and pure gaseous hydrate.

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