• Asian-Australasian Journal of Animal Sciences
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• v.4 no.3
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• pp.285-291
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• 1991

Two experiments were conducted to evaluate the effect of mold inhibitor in the ration which had two different protein levels (18% and 12%) and two different particle sizes (80 or 40% of the particles in the ration less than 1.19 mm). The experimental diets with ave. 12.7% moisture which were treated at the level of 0.1% mold inhibitor were stored under 85% humidity and at $29{\pm}1^{\circ}C$ for 10 to 40 days. In experiment 1, after 40 days of storage the $CO_2$ production in the feed treated with mold inhibitor was higher (p < 0.01) than when 40% of the ration's panicle size was 1.19 mm. Aflatoxin production in the experimental diet with mold inhibitor was affected (p<0.05) by the levels of protein and the different particle size ranges after 40 days storage. The interaction of protein levels and particle size ranges on the anatoxin and $CO_2$ production was significant (p<0.05) at 40 days storage. In experiment 2, there was a decrease in total body weight gain and total feed intake observed in chicks fed the untreated diet of 18% protein with 40% of the particles in the ration less than 1.19 mm stored for 40 days. Feed conversion was depressed (p<0.05) in the chicks fed the untreated diets of both particle sizes. Particle size X types of feed interaction in feed conversion was significant (p<0.05).

• Proceedings of the Korean Geotechical Society Conference
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• 2010.09c
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• pp.55-60
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• 2010

Rockfill zones in CFRD consist typically of large granular materials, usually the maximum particle size up to several meters, which makes laboratory testing to determine the mechanical properties of rockfill difficult. Commonly, the design strength of the rockfills is obtained by scaling down the original rockfill materials and performing laboratory strength tests for the reduced size materials. The objective of the present study is to investigate the effect of particle size on the shear behavior and the strength for granular materials. A series of large-scale triaxial tests was conducted on large granular materials with the maximum particle size varying from 20 to 50mm. The test results showed that overall shear behaviors were similar between the samples with different particle sizes while there were slight differences in the magnitudes of the peak shear stress between the samples. In addition, a simulation of the granular material with the max. particle size of 20mm was performed using DEM code, $PFC^{2D}$, and compared with the test results. The deviatoric stress versus strain behaviors of experimental and numerical tests were found to be matched well up to the peak stress state.

• Journal of the Korean Graphic Arts Communication Society
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• v.14 no.2
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• pp.81-99
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• 1996

The characteristics of printing inks are affected, to a greater or lesser extent, by the size and distribution of the pigment particles in the dispersion. Color strength, transparency and gloss increase with a decrease in particle size of pigments and with an increase in surface area of pigments. On the contrary, opacity and lightfastness tend to increases with an increase in particle size of pigments and with a decrease in surface are and particle size if pigments on the physical properties of printing ink which made up vehicles for sheet fed and organic pigment Lake Red C(C.I Pigment Red 53:1) that different surface area and particle size.

• 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.

• Proceedings of the KSME Conference
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• 2001.06a
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• pp.383-388
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• 2001

Effects of particle property variation of cone crack shape according to impact velocity in silicon carbide materials were investigated. The damage induced by spherical impact having different material and size was different according to materials. The size of ring cracks induced on the surface of specimen increased with increase of impact velocity within elastic contact conditions. The impact of steel particle produced larger ring cracks than that of SiC particle. In case of high impact velocity, the impact of SiC particle produced radial cracks by the elastic-plastic deformation at impact regions. Also percussion cone was formed from the back surface of specimen when particle size become large and its impact velocity exceeded a critical value. Increasing impact velocity, zenithal angle of cone cracks in SiC material was linearly decreasing not effect of impact particle size. An empirical equation, $\theta=\theta_{st}-\upsilon_p(180-\theta_{st})(\rho_p/\rho_s)^{1/2}/415$, was obtained from the test data as a function of quasi-static zenithal angle of cone crack($\theta_{st}$), the density of impact particle(${\rho}_p$) and specimen(${\rho}_s$). Applying this equation to the another materials, the variation of zenithal angle of cone crack could be predicted from the particle impact velocity.

• Particle and aerosol research
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• v.5 no.2
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• pp.63-70
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• 2009

The size distribution and number concentration of atmospheric aerosol were measured and compared using APS 3321 and Dust Monitor 1.108. The particle size distribution and number concentration measured by two devices were also compared at a particle generation system of standard PSL and fly ash. The number concentration of atmospheric aerosol measured by APS was higher than that by Dust Monitor in particle size range of less than $3.0{\mu}m$, but there was good accordance between them in particle size range of over $3.0{\mu}m$. In the particle generation system of PSL and fly ash, different measurement results were shown because the particle concentration was higher than that of atmospheric aerosol. The number concentration measured by Dust Monitor was higher than that by APS in most particle size ranges. However, the peak concentration of PSL particles measured by Dust Monitor was lower than that by APS. The difference of the collection efficiency in a scrubber by APS and Dust Monitor measurement was less than 10%, but in the particle size of $1.5{\mu}m$, it was over 20%.

• Textile Coloration and Finishing
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• v.34 no.4
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• pp.261-271
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• 2022

Waterborne polyurethane(WPU) is greatly affected by its properties depending on the average particle size. In this study, by analyzing the characteristics of WPUs with different average particle sizes according to the DMPA content and we confirmed that the WPU-Ms have different properties from the physical properties of WPU by mixing two types of WPU with different particle sizes in the same volume. At this time, we mixed WPU at an ideal ratio of 7:3 through literature research. In the thermal characteristic analysis, it was confirmed that the thermal decomposition temperature decreased and Tg increased as the content of DMPA, which is the hard segment, increased. In addition, the average particle size of WPU decreased as DMPA increased, and physical properties and adhesive strength were improved due to increased interaction. When mixed with each other in a weight ratio of 7:3, it was observed that adhesion and mechanical properties were improved compared to only WPU.

• Journal of Soil and Groundwater Environment
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• v.22 no.5
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• pp.89-97
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• 2017

In this study, we evaluated effect of particle size on arsenic solid-state speciation and bioaccessibility in soils highly contaminated with arsenic from smelting and mining. Soils were partitioned into six particle size fractions ($2000-500{\mu}m$, $500-250{\mu}m$, $250-150{\mu}m$, $150-75{\mu}m$, $75-38{\mu}m$, <$38{\mu}m$), and arsenic solid-state speciation and bioaccessibility were characterized in each particle size fraction. Arsenic solid-state speciation was characterized via sequential extraction and XRD analysis, and arsenic bioaccessibility was evaluated by SBRC (Solubility Bioaccessibility Research Consortium) method. In smelter site soil, arsenic was mainly present as arsenic bound to amorphous iron oxides. Fine particle size fractions showed higher arsenic concentration, but lower arsenic bioaccessibility. On the other hand, arsenic in mine site soil showed highest concentration in largest particle size fraction ($2000-500{\mu}m$), while higher bioaccessibility was observed in smaller particle size fractions. Arsenic in mine site soil was mainly present as arsenolite ($As_2O_3$) phase, which seemed to affect the distribution of arsenic and arsenic bioaccessibility in different particle size fractions of the mine soil.

• Journal of the Korean Geotechnical Society
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• v.21 no.7
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• pp.13-20
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• 2005

For experimental study on the effect of particle size distribution on the liquefaction resistance strength, particle size distribution curves of the dredged soil were investigated. In this process, four mean particle sizes and three uniformity coefficients were defined representatively and twelve representative particle size distribution curves which have different mean particle size and uniformity coefficient, were defined and manufactured by using the real dredged river soil. Cyclic triaxial tests and resonant column tests were carried out to analyze the effect of mean particle size and uniformity coefficient on the liquefaction resistance strength and dynamic characteristics.

• Journal of the Korean Magnetics Society
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• v.6 no.5
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• pp.334-339
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• 1996

In order to investigate the influence of the magnetic paticle size and its properties on the particulate magnetic material, we evaluated the dispersion of magnetic particles and the electromagnetic properties in magnetic tape made from the magnetic paints by use of each magnetic particles witch were different from particle size and its propertis. The dispersion of magnetic particles depends on the surface chemical properties rather than particle size. As particle size is smaller, the packing ratio of magnetic particle and the magnetic flux density in tape increase. The output levels in playing back of tape incerase in wide frequency range from 315 Hz to 10 kHz and the noises decrease. It is very important to choose the size, the shape, the surface chemical properties and the magnetic properties of the magnetic particle in producing the high quality magnetic tape.