• Tribology and Lubricants
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• 제3권2호
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• pp.44-49
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• 1987

Molecular alignment has been postulated as influencing non-Newtonian behavior of liquid lubricants containing various additives. Four blended lubricants, two synthetic and two mineral were analyzed by FTIR spectroscopy. All of the lubricants exhibited polarization changes in their infrared emission spectra at 60$\circ$C under shear. For this work a special mockup journal bearing was constructed to seperate load and shear effects. At a temperature of 100$\circ$C polarization by shear was always reduced, presumably by Browninn motion. This work should be useful in pointing to the shear-sensitive factors. The presence of of a VI improving additive is manifested by the independence of the infrared emissivity with temperature at several wavelengths; a lubricant without a VI improver generally shows a decrease of emissivity at higher temperature.

• Bulletin of the Korean Chemical Society
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• 제26권2호
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• pp.248-252
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• 2005

Synthetic layered double hydroxides (LDHs), [$Mg_4Al_2(OH)_{12}]CO_3{\cdot}nH_2O$, were prepared in the submicron size of plate-like polycrystals. Anion-exchange reactions with various linear dicarboxylic acids were performed to produce LDH/organic hybrid materials by solvothermal treatment in toluene. X-ray powder diffraction spectra for the products indicated that the interlayer spacings of LDHs remarkably changed, up to 20 $\AA$ when 1,10-decanedicarboxylic acid anions were intercalated as an organic guest. Dicarboxylates-LDHs samples could be also re-exchanged consecutively with other dicarboxylic acids or carbonate without serious destruction of layer structure under the scanning electron microscopic observation.

• 한국염색가공학회지
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• 제10권2호
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• pp.8-17
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• 1998

In this study we have examined electroless chemical plating on the plasma grafted poly [ethylene terephathalate］(PET) fabric in order to improve the interfacial adhesion between metal and fiber. The vapour phase of acrylic acid introduced on the PET surface and the graft polymerization was carried out by using cold plasma, resulting in the grafting yield of 0.8-1.3 wt％. The carboxyl group of the plasma grafted was identified by FT-IR-ATR spectra. The Interfacial adhesion was related to the carboxyl group. After electroless chemical plating of nickel, it showed that the more the carboxyl, the better the interfacial adhesion. Comparing to the untreated, the plasma grafted fabric showed fairly good interfacial adhesion(5B grade, ASTM D3359) . The shielding effect of electromagnetic wave showed 95dB. The shielding effect depends on the fabric structure, the surface structure, and the cross sectional shape of fibers. The dense fabric structure, the etched surface like a microcrater, and the trigonal cross sectional shape were prefered.

• 천문학회보
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• 제35권2호
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• pp.78.1-78.1
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• 2010

We obtained the spectra of 93 Planet host stars and 73 normal field stars in F, G, K type using BOES at BOAO. We measured the equivalent width of Fe and 13 elements lines using the automatic EW measurement program, TAME(Tools for Automatic Measurement of Equivalent-widths) and estimated the abundances by synth and abfind driver of MOOG code. Since the absence of planets in the normal field stars cannot be "completely" proved, this work focused on the chemical abundances and planet properties of planet host stars, which have the massive planets close to the parent star relatively. We carried out an investigation for the difference of abundances between stars with "Hot Jupiter" and normal field stars with no known planets. We examined the chemical composition of 12 elements, such as Na, Mg, Al, Si, Ca, Sc, Ti, V, Cr, Mn, Co, and Ni by EW measurements, and the S abundances were estimated using synthetic spectrum.

• 한국환경과학회지
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• 제12권1호
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• pp.87-92
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• 2003

Synchronous spectrofluorimetry was carried out for the simultaneous determination of various polycyclic aromatic hydrocarbons(PAHs) in aqueous solution by fluorescence spectrometry have been studied. The optimal wavelength interval(${\triangle}{\lambda}$) for synchronous spectra of acenaphthene, anthracene, benzo[a]anthracene, fluorene and pyrene were investigated in the presence of surfactants. The great enhancement of the fluorescence of these PAHs in Triton X-100 was obtained and optimal wavelength was 50 nm. The calibration curves in synthetic mixture solution of 5 PAHs were linear over the range from $1.0{\times}10^{-8}M$ to $1.0{\tiems}10^{-4}M$. Under the optimal experimental conditions, the detection limits were $4.9{\tiems}10^{-9}M$,\;7.0{\times}10^{-9}M,\;4.7{\tiems}10^{-9}M,\;1.6{\tiems}10^{-9}M$ and $3.2{\tiems}10^{-9}M$ for acenaphthene, anthracene, benzo[a]anthracene, fluorene and pyrene, respectively.

• 생약학회지
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• 제1권4호
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• pp.119-124
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• 1970

Evodia daniellii $H_{EMSLEY}$, a plant belonging to Rutaceae, is cultivated in Korea and used as a folkmedicine for gastric inflammation, extermination of noxious insects, and headache. The seed oil of this plant also has been used in various diseases, for example, dermatitis, scabies and so forth. From the barks, fruit peels, and seed oil of Evodia daniellii $H_{EMSLEY}$, four crystalline compounds were isolated. Three compounds except one were characterized as methyl sinapate, bergapten, and evodiamine by m.p. determination, elemental analysis, UV, IR, NMR spectra and mass analysis. Even though methyl sinapate was a known synthetic compound, it was not yet reported as a natural product. From the seed oil, unsaponifiable fraction was separated and was analyzed. It was considered to be consisted with sterols, hydrocarbons and tocopherols.

• 천문학회보
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• 제36권1호
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• pp.60.1-60.1
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• 2011

We present preliminary results of a statistical study on star formation history of infrared luminous galaxies selected from a IRAS-SDSS matched sample. We derive their star formation histories by comparing observed optical spectra and stellar population synthetic model templates. We find that young population fraction (<500 Myr) increases with infrared luminosity, while AGN-host (based on optical line ratios) galaxies show an enhancement of star formation at intermediate age (around 1 Gyr) compared with starburst galaxies. These results support that infrared luminosity is dominated by starburst activity and that there is an evolutionary connection from starburst to AGN.

• 한국염색가공학회지
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• 제12권6호
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• pp.396-403
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• 2000

The purpose of this study was to investigate the dyeing properties of silk, wool, nylon and poly(ethylene teraphtlate)〔PET〕 fabrics dyed with Tumeric(Curcuma longa) extracts. The dyeing property and color fastness were investigated by using the extracts and the post mordanting with Aluminum, Copper and Iron salts. In the UV-visible spectra, the maximum absorption of wavelength of the extract with methyl alcohol appeared at 420nm, and that of the extract with distilled water was at 415nm. Increasing the dyeing temperature, the K/S values of dyed fabrics were increased. The optimum dyeing condition was 30∼60 minute of dyeing time at pH 5∼5.6. Surface colors of silk and wool became dark by using mordants compared to those of nylon and PET fabrics. The drycleaning fastness of fabrics dyed with the extracts was good. The laundering and light fastness were improved by using mordants.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 2006년도 학술발표회 논문집
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• pp.133-140
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• 2006

This paper addresses a fundamental research subject to complement and improve current domestic design specifications for the strong motion duration criterion and the envelop function of artificial accelerograms that can be applied to the earthquake-proof design of nuclear structures. The criteria for design response spectra and strong motion duration suggested by WRC RG 1.60 and ASCE Standard 4-98 are commonly being used in the profession, and they are first compared with each other and reviewed. By applying 152 real strong earthquake records that are over magnitude of 5 in the rock sites to the strong motion duration criterion in ASCE 4-98, an empirical regression model that predicts the strong motion duration as a function of earthquake magnitude is then developed. Using synthetically generated earthquake time histories for the five cases whose strong motion durations vary from 6 to 15 seconds, a seismic analysis is conducted to identify effects of the strong motion durations on the seismic responses of nuclear structures.

• Bulletin of the Korean Chemical Society
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• 제18권1호
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• pp.50-56
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• 1997

The mode of action of mastoparan B, an antimicrobial cationic tetradecapeptide amide isolated from the hornet Vespa basalis, toward phospholipid bilayers was studied with synthetic mastoparan B and its analogs with individual Ala instead of hydrophobic amino acids (1-Ile, 3-Leu, 6-Leu, 7-Val, 9-Trp, 13-Val, 14-Leu) in mastoparan B. Mastoparan B and its analogs were synthesized by the solid-phase method. Circular dichroism spectra showed that mastoparan B and its analogs adopted an unordered structure in buffer solution. In the presence of neutral and acidic liposomes, most of the peptides took an α-helical structure. The calcein leakage experiment indicated that mastoparan B interacted strongly with neutral and acidic lipid bilayers than its analogs. Mastoparan B also showed a more or less highly antimicrobial activity and hemolytic activity for human erythrocytes than its analogs. These results indicate that the hydrophobic face in the amphipathic α-helix of mastoparan B critically affect biological activity and helical contents.