• Journal of the Korean Vacuum Society
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• v.13 no.2
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• pp.59-64
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• 2004

A study on the semiconductor laser-based atomic absorption spectroscopy was performed for monitoring physical vapor deposition process. Gadolinium metal was vaporized with a high evaporation rate by electron beam heating. Real-time atomic absorption spectra were measured by using tunable semiconductor laser beam at 770-794 nm (center wavelength of 780 nm) and its second harmonic at 388-396 nm. Atomic densities of metal vapor can be calculated from the absorption spectra measured. We plot the atomic densities as a function of the electron beam power and compare with the evaporation rates measured by quartz crystal monitor. We demonstrate that the semiconductor laser-based spectroscopic system developed in this study can be applied to monitor the physical vapor deposition process for other metals such as titanium.

• Journal of the Korean Society of Safety
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• v.21 no.1 s.73
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• pp.86-91
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• 2006

Oil spills caused by the accidents have been occurred from house and factory waste, grounded tanker, the rupture of storage tank and oil pipelines, the deterioration of various industrial facilities, etc. Many oil spills result in contamination of shorelines and workplace. Fire and explosion may happen from these spills. There are several technologies used for clean-up application, which include use of oil dispersing agents, absorbents, solidifiers, booms and skimmers by physical, chemical, and biological methods. Methods for oil spill clean-up operation are classified into the absorption type, gel type and self-swelling type. Porous materials with oil absorptive properties are classified into micropore, mesopore, and macropore depending on their pore sizes. Recently, new porous materials with smaller size have been developed, but the selective oil absorption in water-in-oil interface demonstrates the macro pore size. In this study oil absorption effects were evaluated using the organic porous materials with a complex function of gel type and swelling type. Samples were subjected to analysis by FT-IR spectroscopy and were characterized in terms of gel formation and morphologies. Oil sorption capacity, pressure retention force and gel strength were also measured. From these results, the physicochemical reactivity before and after gelation was verified and the industrial applications of clean-up operation were suggested.

• Journal of Microbiology and Biotechnology
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• v.17 no.1
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• pp.138-145
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• 2007

Anabaena sensory rhodopsin is a seven transmembrane protein that uses all-trans/13-cis retinal as a chromophore. About 22 residues in the retinal-binding pocket of microbial rhodopsins are conserved and important to control the quality of absorbing light and the function of ion transport or sensory transduction. The absorption maximum is 550 nm in the presence of all-trans retinal at dark. Here, we mutated Pro206 to Glu or Asp, of which the residue is conserved as Asp among all other microbial rhodopsins, and the absorption maximum and pKa of the proton acceptor group were measured by absorption spectroscopy at various pHs. Anabaena rhodopsin was expressed best in Escherichia coli in the absence of extra leader sequence when exogenous all-trans retinal was added. The wild-type Anabaena rhodopsin showed small absorption maximum changes between pH4 and 11. In addition, Pro206Asp showed 46 nm blue-shift at pH7.0. Pro206Glu or Asp may change the contribution to the electron distribution of the retinal that is involved in the major role of color tuning for this pigment. The critical residue Ser86 (Asp 96 position in bacteriorhodopsin: proton donor) for the pumping activity was replaced with Asp, but it did not change the proton pumping activity of Anabaena rhodopsin.

• Journal of Pharmaceutical Investigation
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• v.6 no.3
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• pp.48-57
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• 1976

An enhancement in the dissolution rate of the drug should facilitate its GI absorption if the absorption process is dissolution rate limited. One of the need for the techniques that can potentially enhance the dissolution rate and extent of absorption of hydrophobic drugs is the formation of coprecipitates with pharmacologically inert, polymeric materials. The physicochemical modification offers the advantage of possibly enabling one to administer the drug orally in a form from which it is most available for GI absorption. Several $investigation^{1-15)}$ demonstrated that the formation of solid dispersions or coprecipitates of relatively water-insoluble drugs with various pharmacologically inert carriers can increase singnificantly their in vitro dissolution rates. However, little information is available in the literature related to the dissolution rate patterns of furosemide, a water-insoluble diurectices, with respect to the sort of copolymer and the ratio of coprecipitates as a function of time, respectively. The purpose of the present investigation was to ascertain, the general applicability of the copolymers to use fore more fast, enhanced dissolution techniques of furosemide. To accomplish the need for enhancement in the dissolution rate of furosemide, varying ratio coprecipitates with different water-soluble polymers, such as polyvinylpyrrolidone (PVP), polyethylene glycol 4000(PEG 4000), and polyethylene glycol 6000 (PEG 6000), were quantitatively studied by comparing their dissolution characteristics of furosemide. The dissolution patterns of pure furosemide, varying ratio furosemide-PVP coprecipitates, (1:2, 1:5, and 1:9(w/w)), furosemide-PEG 4000 coprecipitates (1:4, 1:9, and 1:19(w/w), furosemide-PEG 6000 coprecipitates(1:4, 1:9, and 1:19(w/w)), and the same ratio physical mixtures, respectively, were compared by the amount dissolved as a function of time.

• Journal of Nutrition and Health
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• v.28 no.1
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• pp.23-32
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• 1995

This study was performed to investigate the influence of dietary fibers from the whole foods on the serum lipid level and bowel function in rats. The fiber sources of experimental diets were prepared by drying and milling of cereal(rice bran), vegetables(Korean cabbage, radish), fruit(apple), and sea weeds(laver, sea tangle). Each of fiber sources was mixed into the diet to make the 5% level of total dietary fiber. Male rats of Sprague-Dawley strain were blocked into 8 groups : FF, CC, CE, V1, V2, ER, S1, and S2. The animals were fed ad libitum each of experimental diets for 4 weeks. Serum triglyceride level was not significantly different among groups. The laver group showed the lowest level in the serum total cholesterol. The Korean cabbage group showed the highest level in the serum HDL cholesterol. The longest transit time was observed in the fiber free group and the shortest transit time was observed in the sea tangle group. Absorption rates of calcium were especially lower in the Korean cabbage and the sea tangle groups than the other groups. Magnesium and phosphorus absorption rates were influenced by SDF(Soluble Dietary Fiber) intake and TDF(Total Dietary Fiber) intake, respectively. Mucosa weight in the small intestine showed the tendency to increase by increasing of IDF (Insoluble Dietary Fiber) intake. especially the Korean cabbage group was the heaviest. The activity of maltase in the mucosa of small intestine was the lowest in the radish group.

• Ceramist
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• v.10 no.3
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• pp.86-90
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• 2007

Novel photochromic oxide glasses are presented in this section. These glasses are based on phosphate formers containing both tungsten and antimony atoms. Exposure to visible continuous or pulsed laser beam results in an intense photochromic effect witch is shown to occur in the volume of the glass and results in a broad absorption band in the visible and near infrared. This effect was not identified to be related with a structural change and is assumed to be entirely electronic. A change in the absorption coefficient is observed in function of tungsten content, exposure time and increases with beam power. These glasses have been investigated regarding the possibility of holographic data storage using visible lasers sources. Changes in both refractive index and the absorption coefficient were measured using a holographic setup. The modulation of the optical constants is reversible by heat treatment.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2000.04a
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• pp.181-188
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• 2000

This paper describes the energy absorption of a square tube under axi compression by using the finite element method. The overall deformations and lo buckling modes of tube was discussed by "plastic hinge concep Force-displacement function was plotted to show various state that depended or time. Also, mean crush load was expressed as a type of section geometry a material property using dimensional analysis. To verify the energy absorption and the effects of dimensions, The standards Wt used as related density and specific energy, mean crushing load and the resL were discussed by the relation between crush load and deformation, the relati between related density and specific energy, the relation between crush load a mean crush load, the relation between mean crush load and specific energy.ergy.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.2059-2065
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• 2008

In this paper, quasi-static crushing tests of composite circular tubes under axial compression load are conducted to investigate the energy absorption characteristics. Circular tubes used for this experiment are glass/epoxy (GFRP) composite tubes, which is fabricated by the filament winding method. One edge of the composite tube is chamfered to reduce the initial peak load and to prevent catastrophic failure during crushing process. Two suggested trigger mechanisms for the composite tubes are investigated. Crushing modes are mainly affected by thickness/diameter ratio, and average crushing loads are mainly affected by their cross-sections. Energy absorption characteristics vary significantly as a function of the tube geometry, trigger mechanism, t/D ratio and the cross-sectional shape.

• Bulletin of the Korean Chemical Society
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• v.32 no.3
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• pp.905-908
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• 2011

We report fluorescence excitation and emission spectra of the CHBr molecule generated via pyrolysis of $CH_3Br$ in a molecular beam experiment. The 193 nm attenuation cross sections were estimated from the reduction of the CHBr signal as a function of the excimer laser fluence. The derived 193 nm absorption cross section for CHBr [$(3.24{\pm}0.59){\times}10^{-17}\;cm^2$] is slightly higher than the absorption cross section previously determined for CHCl [$(2.6{\pm}0.8){\times}10^{-17}\;cm^2$], but the difference is within the estimated uncertainties in the measured cross section.

• Journal of the Korean Institute of Rural Architecture
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• v.2 no.3
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• pp.85-97
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• 2000

In the organizing principle of Hwaeomsa temple, we could see the procedure of absorption and combination on folk beliefs and Buddhism like other temples. One of Representative folk beliefs took in and combined in its temple is Sam-Sung-Gak, which is located at the same place with Won-Tong-Geon. And Myong-Bu-Geon is affected by the Ten-Kings belief of Taoism very deeply, is also very rare folk belief case grown naturally. The diversification of Buddhist sanctum' function is absorption and combination between proper belief for the Buddhist Goddess of Mercy and folk native beliefs.