• Journal of Power System Engineering
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• v.4 no.1
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• pp.74-80
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• 2000

This present study was investigated effect of Ni contents on the high temperature strength characteristic in 9Cr ferritic heat-resistant steel added 1.7%W in place of Mo in order to restraint laves phase formation. Precipitation amount of carbide, number of particle per unit area and particle size of carbide were decreased with increase of Ni content. In the steels, carbides of $M_{23}C_6$ type was mainly precipitated, but laves phases could not precipitated. Tensile and yield strength, creep strength and creep rupture time was decreased, but elongation were increased due to decreasing of particle number per unite area and carbide amount precipitated with increase of Ni content.

• Transactions on Electrical and Electronic Materials
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• v.14 no.2
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• pp.105-109
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• 2013

In order to develop high voltage (HV) insulation materials, epoxy/spherical alumina composites with two different particle sizes (in ${\mu}m$) were prepared and a dynamic mechanical analysis (DMA) and electrical insulation breakdown strength test were carried out in sphere-sphere electrodes and the data were estimated using Weibull statistical analysis. Alumina content varied from 50 to 70 wt%. The electrical insulation breakdown strength for epoxy/alumina (50 wt%) was 44.0 kV/1 mm and this value decreased with increasing alumina content. The effects of insulation thickness and alumina particle size on the insulation breakdown strength were also studied. The insulation thickness varied from 1 mm to 3 mm, and the particle sizes were 7.3 or $40.3{\mu}m$.

• Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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• 2006.06b
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• pp.479-484
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• 2006

The pore structures of paper were modified by the application of the blending of pulp, refining, and filler particle size and ash content. It was conformed that the reflectivity of paper can be modified by the combination of above parameters. It was also found that the modifications of reflectivity of paper were very close relation with pore structure, such as average pore size, pore size distribution and porosity. The average pore size was decreased with addition of HwBKP, but showed smaller particle size than those made from 100% HwBKP. Refining of pulp decreased both average pore size and the reflectivity of paper. The pore size distribution of filled paper can be varied by the combination of filler particle size and ash content.

• Applied Chemistry for Engineering
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• v.7 no.6
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• pp.1147-1155
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• 1996

In the spray drying with rotating wheel atomizer of cheese powder, the relationships among variables were analyzed with Response Surface Methodology in which several independent variables such as total solid content, wheel rotation speed, and outlet temperature influenced dependent variables such as particle diameter, moisture content, bulk density, and viscosity of suspended liquid. Significance and correlation were tested according to central composite design. As a results of analyzing the correlations between independent and dependent variables, particle diameter and moisture content of cheese powder were decreased with increasing wheel rotation speed, and bulk density was decreased with increasing outlet temperature. Viscosity of suspended liquid were increased with increasing wheel rotation speed and total moisture content. In correlation among dependent variables, moisture content was proportional to bulk density, and particle diameter was inversly proportional to moisture content and bulk density.

• Animal Bioscience
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• v.34 no.9
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• pp.1491-1498
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• 2021

Objective: This research was carried out to investigate the effects of corn particle size on the apparent total tract digestibility (ATTD) of energy and nutrients fed to pigs at four different growth stages and therefore to provide basis for better application of corn in pig feeds. Methods: Eighteen weanling piglets, 18 growing barrows, 24 gestating sows and 24 lactating sows were used in this study. Within each stage, pigs were allotted to 1 of 3 or 4 corn-soybean meal diets which were formulated with different corn particle size in a completely randomized design with 6 replicate pigs per diet. Each stage lasted for 19 days, including 7 days for cages adaptation, 7 days for adaptation to diets and followed by 5 days for total collection of feces and urine. Results: For nursery and growing stages, the results showed that digestible energy content and ATTD of gross energy (GE), dry matter (DM), neutral detergent fiber (NDF), and acid detergent fiber (ADF) was increased (p<0.05) as the corn particle size reduced. Meanwhile, the metabolizable energy content and ATTD of crude protein (CP) tended to increase. For gestating sows, no differences were found in the ATTD of nutrients among dietary treatments. As for lactating sows, there were linear and quadratic increases (p<0.05) in the ATTD of DM, GE, NDF as the corn being finer milled. Quadratic response in ATTD of ADF and CP (p<0.05) were observed as sows fed with four different diets. Conclusion: Reducing corn particle size can increase digestibility of nutrients fed to young pigs and lactating sows. No effects were observed in present experiment when gestating sows were fed with different particle sized corn.

• Journal of the Korean Wood Science and Technology
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• v.30 no.3
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• pp.48-58
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• 2002

This study was carried out through scanning electron microscopy to elucidate the mechanism of thickness swelling in wood particle-polypropylene composite which is a typical way of using wood and plastic materials. For this purpose, control particleboards and nonwoven web composites from wood particle and polypropylene fiber formulations of 100:0, 70:30, 60:40, and 50:50 were manufactured at target density levels of 0.5, 0.6, 0.7, and 0.8 g/cm³. Their water absorption and thickness swelling were tested according to ASTMD 1037-93 (1995). To elucidate thickness swelling mechanism of composite through the observation of morphological change of internal structures, the specimens before and after thickness swelling test by 24-hour immersion in water were used in scanning electron microscopy. From the scanning electron microscopy, thickness swelling of composite was thought to be caused by the complicated factors of degree of built-up internal stresses by mat compression and/or amount of wood particles encapsulated with molten polypropylene fibers during hot pressing. In the composites with wood particle contents of 50 to 60% at target densities of 0.5 to 0.8 g/cm³ and with wood particle content of 70% at target densities of 0.5 to 0.7 g/cm³, thickness swellings seemed to be largely dependent upon the restricted water uptake by encapsulated wood particles with molten polypropylene fibers. Thickness swelling in the composite with wood particle content of 70% at target density of 0.8 g/cm³, however, was thought to be principally dependent upon the increased springback phenomenon by built-up internal stresses of compressed mat.

• Journal of Powder Materials
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• v.7 no.1
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• pp.27-34
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• 2000

The fabrication process and mechanical properties of SiC particle prefrrms with high volume fraction ranged 50∼71% were investigated to make metal matrix composites for possible applications as heat sinks in electronic packares. The SiC particle preforms with 50∼71vol% of reinforcement were fabricated by a new modified process named ball milling and pressing method. The SiC particle performs were fabricated by ball milling of SiC particles with single sized of 48${\mu}$m in diameter or two different size of 8${\mu}$m and 48${\mu}$min diameter, with collodal SiO2 as inorgnic binder in distilled water, and the mixed slurries were cold pressed for consolidation into final prefom. The compressive strengths og calcined SiC particle prefoms increased from 20MPa to 155MPa with increasing the content of inorganis binder, temperature and time for calcination. The increase of compressive strength of SiC particle bridge the interfaces of two neighboring SiC particles.

• Journal of Magnetics
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• v.21 no.2
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• pp.244-248
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• 2016

Aiming to improve the shear yield stress of magnetorheological fluid, magnetorheological fluids with different particle characteristics are prepared, and the influence rules of particle mass fraction, particle size, nanoparticles content and application temperature on shear yield stress are investigated. Experimental results indicate that shear yield stress increases approximate linearly with the enhancement of particle mass fraction. Particle size and the nanoparticles within 10% mass fraction can improve the shear yield stress effectively. When the application temperature is higher than $100^{\circ}C$, the shear yield stress decreases rapidly because of thermal expansion and thermal magnetization effect.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.34 no.1
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• pp.22-29
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• 2002

The coated paper was greatly affected by the basic physical properties of the binder as well as the amount of the coating formula. High glass transition temperature (Tg) of the styrene-butadiene (SB) latex, selected as the binder in our study, gave the high stiffness to the coated paper, but lowered the binding force and print gloss. The average particle size of the SB latex also greatly affected to the coated paper so that the smaller particle size improved the rheological property of the coating formula and increased the binding force and print gloss. Another property of the SBR latex, gel content, was important because when its value was small, the latex was easily deformed at the high temperature and increased air permeability to the coated paper. Therefore, the lower gel content consequently resulted in the higher blistering resistance, especially in the web paper. The larger portion of the SB latex in the coated formula improved the binding force and print gloss, but decreased the ink set-off and ink-trapping to the coated paper. The heavier coating improved optical properties such as opacity, paper gloss and paper smoothness, to the coated paper.

• Macromolecular Research
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• v.12 no.2
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• pp.213-218
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• 2004

We have performed dispersion polymerization of acrylamide in tert-butyl alcohol/water mixture-using hydroxypropyl cellulose and ammonium persulfate as the stabilizer and the initiator, respectively - to study the effects that the concentration of monomer, initiator, and stabilizer, the tert-butyl alcohol/water ratios as polymerization media, and the reaction temperature have on, among other things, the polymerization kinetics, particle sizes, and molecular weights. The polymerization rate increased upon increasing the concentration of the monomer, initiator, and stabilizer, the water content in the tert-butyl alcohol/water media, and the polymerization temperature. The average particle size of the lattices increased upon increasing the concentration of initiator, the polymerization temperature, and the water content in the tert-butyl alcohol/water media, but it decreased upon increasing the concentration of monomer and stabilizer. The viscosity-average molecular weight increased upon increasing the concentration of monomer and stabilizer and the water content in the tert-butyl alcohol/water media, but it decreased upon increasing both the concentration of initiator and the polymerization temperature.