• Title/Summary/Keyword: Instrumental analyses

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Microstructural and Mechanical Characterization of Nanocomposite Ti-Al-Si-N Films Prepared by a Hybrid Deposition System (하이브리드 증착 시스템에 의해 합성된 나노복합체 Ti-Al-Si-N 박막의 미세구조와 기계적 특성)

  • 박인욱;최성룡;김광호
    • Journal of the Korean institute of surface engineering
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    • v.36 no.2
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    • pp.109-115
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    • 2003
  • Quaternary Ti-Al-Si-N films were deposited on WC-Co substrates by a hybrid deposition system of arc ion plating (AIP) method for Ti-Al source and DC magnetron sputtering technique for Si incorporation. The synthesized Ti-Al-Si-N films were revealed to be composites of solid-solution (Ti, Al, Si)N crystallites and amorphous Si3N4 by instrumental analyses. The Si addition in Ti-Al-N films affected the refinement and uniform distribution of crystallites by percolation phenomenon of amorphous silicon nitride, similarly to Si effect in TiN film. As the Si content increased up to about 9 at.%, the hardness of Ti-Al-N film steeply increased from 30 GPa to about 50 GPa. The highest microhardness value (~50 GPa) was obtained from the Ti-Al-Si-N film haying the Si content of 9 at.%, the microstructure of which was characterized by a nanocomposite of nc-(Ti,Al,Si) N/a$-Si_3$$N_4$.

Preparation and Characterization of Silk Fibroin Nanoparticles

  • Kweon, Hae-Yong;Yeo, Joo-Hong;Woo, Soon-Ok;Han, Sang-Mi;Jo, You-Young;Lee, Kwang-Gill
    • International Journal of Industrial Entomology and Biomaterials
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    • v.20 no.1
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    • pp.25-28
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    • 2010
  • Silk fibroin was conjugated with methoxypoly(ethylene glycol) derivatives to prepare silk nanoparicles. Conjugation of SF with PEG was examined with various instrumental analyses. Nuclear magnetic resonance spectrometry and amino acid analysis showed that serine and tyrosine residues in SF were reacted with PEG and resulted in increasing molecular weight. The sizes and shapes of SF nanoparticles observed by transmission electronmicroscope were ranged about 150-400 nm in diameter and spherical morphology. UV/VIS spectrometry showed SF nanoparticles might be outer PEG and inner SF structure.

Effect of Leakage on Deterioration of Concrete Lining Structure (콘크리트 라이닝 구조물의 누수에 의한 열화특성)

  • Jung, Ho-Seop;Kim, Dong-Cyou;Kim, Seong-Soo;Park, Kwang-Pil
    • Proceedings of the Korea Concrete Institute Conference
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    • 2009.05a
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    • pp.287-288
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    • 2009
  • In this study, the degree of deterioration on the tunnel lining concrete due to crack and leakage was evaluated by field-investigating the conventional tunnels constructed a long time ago. By examining the exterior, conducting the non-destructive test and collecting cores for the tunnel concrete linings, this study evaluated the compressive strength and the permeability, and also performed instrumental analyses.

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POLARIZATION AND POLARIMETRY: A REVIEW

  • Trippe, Sascha
    • Journal of The Korean Astronomical Society
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    • v.47 no.1
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    • pp.15-39
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    • 2014
  • Polarization is a basic property of light and is fundamentally linked to the internal geometry of a source of radiation. Polarimetry complements photometric, spectroscopic, and imaging analyses of sources of radiation and has made possible multiple astrophysical discoveries. In this article I review (i) the physical basics of polarization: electromagnetic waves, photons, and parameterizations; (ii) astrophysical sources of polarization: scattering, synchrotron radiation, active media, and the Zeeman, Goldreich-Kylafis, and Hanle effects, as well as interactions between polarization and matter (like birefringence, Faraday rotation, or the Chandrasekhar-Fermi effect); (iii) observational methodology: on-sky geometry, influence of atmosphere and instrumental polarization, polarization statistics, and observational techniques for radio, optical, and $X/{\gamma}$ wavelengths; and (iv) science cases for astronomical polarimetry: solar and stellar physics, planetary system bodies, interstellar matter, astrobiology, astronomical masers, pulsars, galactic magnetic fields, gamma-ray bursts, active galactic nuclei, and cosmic microwave background radiation.

Composition and Evaluation of the Thermal Desorption-Gas Chromatographic System for the Measurement of Volatile Organic Compounds in Air (공기 중 휘발성 유기화합물의 측정을 위한 열탈착-분석시스템의 구성 및 평가)

  • 이수형;송희남;김희갑
    • Environmental Analysis Health and Toxicology
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    • v.17 no.1
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    • pp.63-71
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    • 2002
  • The thermal desorption-gas chromatographic (TD-GC) system has been constructed for the measurement of volatile organic compounds. The thermal desortion unit is composed of four major parts: 1) the control part; 2) the thermal desorption part; 3) the focusing part; and 4) the injection part. The peltier element was introduced to the focusing part for the temperature of the focusing tube to reach-35$^{\circ}C$. The system was tested for the linearity of the calibration curves and reproducibility of instrumental analyses using some disinfection by-products (DBPs) and BTXs (benzene, toluene and p-xylene). The coefficients of determination (r$^2$) for all the calibration curves made were higher than 0.998, and the coefficients of variation (CV) for triplicate measurements were all within 10%. The system also has been tested for field applicability. The analysis of field samples showed that there was no breakthrough problem in the sampling system and that the system could be applied to field measurements.

Analyses of Harmful Substances in Textile Products according to the European Eco-Label Criteria - I (에코라벨 기준에 의한 국내 섬유제품의 분석-I)

  • 최은경;조영달;박경수;이현경
    • Textile Coloration and Finishing
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    • v.15 no.5
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    • pp.340-347
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    • 2003
  • Present situation of Korean textile products regarding European eco-label criteria was assessed by analyzing harmful substances including pH, PCP & TeCP, formaldehyde, heavy metals, cleavable arylamines, allergenic dyes, pesticides, organic carriers, TBT as well as color fastness as the minimum quality requirement. Fabric specimens were submitted from six typical textile companies for product eco-testing. In six product groups selected, arylamines, allergenic dyes, halogenated organic carriers and color fastness were found to be parameters that failed to meet the criteria. Source elucidation of harmful substances were presented with their instrumental analysis results.

Purification and Properties of Non-Cariogenicity Sugar Produced by Alkalophilic Bacillus sp. S-1013

  • Ryu, Il-Hwan;Kim, Sun-Sook;Lee, Kap-Sang
    • Journal of Microbiology and Biotechnology
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    • v.14 no.4
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    • pp.751-758
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    • 2004
  • The NCS(Non-Cariogenicity Sugar) from Bacillus sp. S-1013 was purified by cold acetone and methanol precipitation, and DEAE-cellulose ion-exchange and Sephadex G-100 column chromatographies, to yield an amorphous yellow syrup. The melting point and $[\alpha]_D^{20}$ were 155-$157^{\circ}C$ and +53, respectively. Instrumental analyses such as FT-IR, $^1H-NMR, and ^{13}C-NMR$ showed that the NCS contained an O-H group, C-H, C=O, $NH_2$, anomeric carbon, anomeric proton, N-acetylgalactose, fucose, and neuramic acid, thus, the NCS was determined to be a trisaccharide of Fuc($1\longrightarrow4$)GalNAc($2\longrightarrow6$) NeuAc.

Flavonol Glycosides from Parthenocissus tricuspidata Leaves (담쟁이덩굴엽의 플라보놀 배당체)

  • 황현경;성환길;황완균;김일혁
    • YAKHAK HOEJI
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    • v.39 no.3
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    • pp.289-296
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    • 1995
  • For the investigation of medicinal resources the studies were carried out to evaluated the pharmaco-constituents in the Leaves of Parthenocissus tricuspidata(Vitaceae), of which leaves have been used in Korea as folk remedies for the treatments of arthritis, jaundice, toothache, neuralgia, and etc. From 1-butanol fraction of the MeOH extract, Compound I ($C_{21}H_{18}O_{13}$, Quercetin-3-O-$\beta$-D-glucuronopyranoside), Compound II ($C_{21}H_{20}O_{12}$, Quercetin-3-O-$\beta$-D-glucopyranoside) and Compound III ($C_{25}H_{28}O_{12}$, Quercetin-3-O-(6"-n-butyl)-$\beta$-D-glucuronopyranoside) were isolated by column chromatographic separation using Sephadex LH-20 and ODS gel. Their structures were elucidated through instrumental analyses, such as $^{1}H$-NMR, $^{13}C$-NMR, IR, UV, El-Mass, FAB-Mass and GC. Especially compound III was Flavonol glycoside and named parthenosin.

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A Study on the Sensory and Texture Characteristics of Bread with Roasted Soybean Powder (볶은 콩가루 첨가량을 달리하여 제조한 식빵의 관능적 기계적 특성 연구)

  • 정해옥;임상선;정복미
    • Korean journal of food and cookery science
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    • v.13 no.3
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    • pp.266-271
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    • 1997
  • The effect of partial replacement of flour with roasted soybean powder (0, 5, 10, 15, 20%) was examined by sensory and instrumental analyses of the bread. There were no significant changes in specific loaf volume up to 10% of replacement. Although the hardness of the bread increased with increasing storage time at higher replacement, there were no differences in springiness and cohesiveness compared with control. The yellow color of the soybean powder was reflected in the bread, however, it did not affect the preference. Overall, the bread with 10-15% soybean powder suggested to be acceptable.

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The Effects of Addition of O1igosaccharide on the Quality Characteristics of Tomato Jam (올리고당의 첨가가 토마토잼의 품질특성에 미치는 영향)

  • 김기숙;채윤경
    • Korean journal of food and cookery science
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    • v.13 no.3
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    • pp.348-355
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    • 1997
  • As a trial to expand the use of oligosaccharide, tomato jams were made with various kinds and addition rate levels of oligosaccharide and their quality characteristics were evaluated by instrumental analyses and sensory evaluation. As the addition rate of oligosaccharides increased, 1. the sweetness of tomato jams decreased compared to those of control containing sugar, 2. the lightness and yellowness were increased, however, the redness was decreased, 3. the hardness and adhesiveness of tomato jams containing liquid type oligosacchairdes were lower and those of powder type were higher than control. The springiness of the samples containing oligosaccharide was lower than that of control, however, there was no significant difference in cohesiveness. In sensory evaluation, tomato jams containing oligosaccharides were generally similar or better than control. Color, viscosity, flavor and overall acceptability of the samples containing powder type oligosaccharide were higher than those of liquid type. Tomato jams containing 15% powder type oligosaccharide and 35% sugar showed the highest overall acceptability.

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