• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2006.05a
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• pp.145-149
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• 2006

As the minimum feature size decreases, it is more difficult to control critical contaminant particles. For 16GB flash memory introduced by Samsung a few months ago, 50nm process was used and in this case, contaminant particles as small as 25nm should be control led. The particle beam mass spectrometer (PBMS) was developed to directly sample particles at pressures down to 100 mtorr. This instrument is sensitive to small particles (>5nm) produced in low concentrations ($>20cm^{-3}$). The PBMS has proved to be effect ive in measuring particles generated during semi-conductor fabrication processes, such as low-pressure chemical vapor deposition (LPCVD) of thin films. The operating principle of the PBMS and some measurement results are reviewed in this paper.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.24 no.3
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• pp.59-64
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• 1998

In order to lower porosity of the porous silica, titanium alkoxide solution was filled in the pore of silica in the heating-vacuum condition. The specific surface area of modified samples was decreased effectively from 900 m$^2$/g to 100 m$^2$/g. (The aggregation phenomena in modified samples were improved fairly.) Samples were heated at 600 , and then the titanium alkoxide in the pore was decomposed completely to titanium oxide from TGA-DTA measurement. From SEM result, it was evident that titanium oxide did not coat the surface of the silica. The modified samples were analyzed using SEM, DTA-TGA, BET, and UV-visible spectrometer.

• Journal of the Korean Applied Science and Technology
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• v.28 no.2
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• pp.247-250
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• 2011

The excess volumes of mixing of benzyl alcohol and halothane in vesicle and in suspensions of several lipids have been determined at $25^{\circ}C$ it using a excess volume dilatometer. The potency of general anesthetics has long been known to correlate with lipid solubility. Denaturations of the vesicle, which is a sole membrane protein in the purple membrane of Halobacteriun Halobium, were studied by absorption changes at 280 nm and fluorescence changes at 330 nm and excess volume dilatometer. The particle size analysis of viscous polymer solutions by diffusional interchange is the key step by measurement. The excess volume of mixing in chitosan was found to be negative, whereas them of purple membrane, Halobacteriun Halobium and red membrane were positive in benzyl alcohol and halothane. This result was confirmed as Miller's supposition.

• Journal of the Korean Society of Food Science and Nutrition
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• v.20 no.6
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• pp.653-662
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• 1991

aThe terms of hard and soft as applied to wheats are descriptions of the texture of the kernel. A hard wheat kernel required greater force to cause it to disintegrate than those a soft wheat kernel. Factors than can affect the measurement of hardness outnumber those that affect hardness itself. Kernel texture is the most important single characteristic that affects the functionality of a common wheat. It affect the way in which must be tempered for milling ; the yield and the particle size, and density of flour particles ; and the end use properties in milling, breadmaking, production of soft wheat products, and noodle-making. Papers are reviewed from various sources not only hardness but flour functionality.

• Journal of ILASS-Korea
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• v.10 no.2
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• pp.32-40
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• 2005

This paper presents the analytical approaches to predict cutting fluid aerosol formation characteristics in machining process. The prediction model which is based on the rotary atomization theory analyzes aerosol behaviors in terms of size and concentration. Experiments were tarried out to verify the aerosol formation prediction model under various operational conditions. The experimental results which are obtained by Dual-PDA measurement show resonable agreement with prediction results of aerosol concentration. This study can be provided as a basis to estimate and control the hazardous cutting fluid aerosol in machining process in view of environmental consciousness.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2002.05a
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• pp.224-233
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• 2002

A common YBCO powder has been made from a mixture of Y123 and Y211 that heated at different temperatures, respectively. The synthesis temperature of Y211 is lower than Y123. If Y211 has been heated as a synthesis temperature of Y123, a particle size of it may be very coarse. It exist as one of main defects for superconductor. But We simultaneously synthesize a YBCO(its composition is (Y123+0.4Y211)+$lwt%CeO_2$) using polymeric complex method. In the YBCO, the Y123 is synthesized lower temperature than other methodes, and its crystal structure is orthorombic. For measurement of these superconducting properties, we fabricated a YBCO single crystal. The manufactured YBCO single crystal is measured a magnetic distribution device using 0.5Tesla magnet and trapped magnet fields in it are 0.2Tesla.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2008.11a
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• pp.6-7
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• 2008

Composite nanoparticles of silica-polyaniline were synthesized and tested as an electrochromic material. For the optical application, the size of the nanoparticle was intended to be less than 100 nm in diameter. The synthesis was done by using a microemulsion synthesis method where the silica-polyaniline composite nanoparticle was obtained by dispersing two acidic aqueous phases containing aniline and polymerization agent, respectively. Microstructure analysis such as TEM and BET surface area measurement showed the possibility that polyaniline is incorporated in porous silica structure. The composite structure of the particle was proved to enhance chemical stability of the prepared electrochromic film.

• Proceedings of the KIEE Conference
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• 2005.07c
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• pp.1936-1938
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• 2005

$Al(OH)_3$ is added to the silicone rubber for improvement of its resistance against surface discharge. In this paper, four kinds of $Al(OH)_3$ were added to the SIR during compounding. SIR was deteriorated by a corona treatment. Hydrophobicity recovery rate after corona treatment and arc resistance of SIR were investigated. Hydrophobicity recovery rate of SIR was evaluated by the measurement of contact angle. Arc resistance was evaluated by measuring weight loss of SIR after arc resistance test.

• Journal of Powder Materials
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• v.11 no.3
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• pp.242-246
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• 2004

FePt nanoparticles for high-density magnetic recording media were synthesized by the simultaneous chemical reduction of Fe(acac) $_2$ and Pt(acac) $_2$ with 1,2-hexadecanediol as the reducing reagent. TEM images showed that the shape of as-synthesized FePt nanoparticle was spherical and average particle size was 3 nm. Also, SAD pattern showed that crystal structure was disordered FCC (face centered cubic). These FCC structured nanoparticles were transformed FCT (face centered tetragonal) structure by annealing at 55$0^{\circ}C$ for 30 min in Ar atmosphere. XRD analysis revealed that as-synthesized FePt nanoparticles were transformed from disordered FCC to ordered FCT. Finally, the coercivity of 2 kOe for FePt nanoparticles with FCT structure was obtained by VSM measurement.

• Asian Journal of Atmospheric Environment
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• v.5 no.3
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• pp.157-163
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• 2011

Atmospheric aerosol deposition caused by Asian dust (KOSA) events provide nutrients, trace metals, and organic compounds over the Pacific Ocean that enhance ocean productivity and carbon sequestration and, thus, influence the atmospheric carbon dioxide concentrations and climate. Using dust particles obtained from the snow layers on Mt. Tateyama and the surface sand of Loess Plateau in incubation experiments with natural seawater samples on a shipboard, we demonstrate that dust-particle additions enhanced the bacterial growth on the first day of incubation. Gram-positive bacterial group and alpha-proteobacteria were specifically detected form seawater samples including the mineral particles. Although the remarkable dynamics of trace elements and nutrients depend on dust-particle additions, it is possible that organic compounds present in the mineral particles or transported microbial cells could also contribute to an increase in the quantities of bacteria. The chlorophyll concentrations at fractions of every size indicated a similar pattern of change between the seawater samples with and without the dust-particle additions. In contrast, the chlorophyll measurement using submersible fluorometer revealed that the dynamics of phytoplankton composition were influenced by the dust-particles treatments. We conclude that the phytoplankton that uses the bacterial products would increase their biomass. We show that KOSA deposition can potentially alter the structures of bacterial communities and indirectly influence the patterns of marine primary production in the Pacific Ocean.