• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.36 no.2
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• pp.17-23
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• 2004

The effects of refining consistency and plate gap on the specific energy consumption and physical properties of liner were investigated. Higher refining consistency and narrower plate gap brought about the reduction of specific energy consumption to decrease the freeness. Refining consistency and plate gap did not affect the bulk, Taber stiffness and compression index. The reduction of freeness and/or the increase of specific energy consumption caused the decrease of bulk and Taber stiffness, but increased the compression index. The effect of grammage on bulk was not observed, but Taber stiffness and compression index were increased with grammage. The bulk was decreased with the reduction of freeness rapidly at the above 400 mL CSF, and then levelled off. It is expected that the reduction of energy consumption could be obtained from the application of higher refining consistency and narrower plate gap during refining.

• Journal of Korean Ophthalmic Optics Society
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• v.20 no.3
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• pp.349-354
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• 2015

Purpose: To investigate the changes of corrective values of astigmatism caused by the position of circle of least confusion on retina in refining astigmatic test using cross cylinder. Methods: 62 subjects (115 eyes) aged $22.24{\pm}2.48$ years participated for this study. After astigmatic test using a radial chart, refining test was performed using a cross cylinder in a condition of maximum plus to maximum visual acuity (MPMVA). Astigmatic refining test was repeatedly performed in each condition of which S+0.75 D, S+0.50 D, S+0.25 D, S-0.25 D, S-0.50 D, and S-0.75 D are added to spherical lenses of MPMVA. The measured values were compared with the values in MPMVA condition. Results: As compared with values in condition of MPMVA, change of astigmatic axis was increased with add the power of (+) spherical lenses and (-) spherical lenses. In same spherical condition, change of astigmatic axis was decreased with increment of astigmatic power (p<0.05). The corrective power of astigmatism was reduced with increment of (+) spherical lenses (p<0.05), and was raised with increment of (-) spherical lenses compared with the power in MPMVA condition. In case of adding (+) spherical lenses, difference of astigmatic power increased with increment of corrective astigmatism power in same test condition. Conclusions: In order to obtain a proper values for corrective astigmatism, position of circle of least confusion should be accurately adjusted before the performing an astigmatism's refining test.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.31 no.1
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• pp.39-45
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• 1999

Refining in papermaking plays an important role in changing fiber properties as well as paper properties. The major effects of refining on pulp fibers are internal and external fibrillation, fiber shortening, and fines formation. Many workers showed that internal fibrillation of the primary refining effects was most influential in improving paper properties. In particular, refining produces separation of fiber walls into several lamellae, thus causing fiber wall swelling with water penetration. This leads to the increase of fiber flexibility and of fiber-to-fiber contact during drying. If the fibers are very flexible, they will be drawn into close contact with each other by the force of surface tension as the water is removed during the drainage process and drying stages. In order to study the effect of fiber wall delamination on paper properties, cross-sectional image of fibers in a natural condition had to be generated without distortion. Finally, it was well recognized that confocal laser scanning microscope (CLSM) could be one of the most efficient tool for creating and quantifying fiber wall delamination in combination with image analysis technique. In this study, the CLSM could be used not only to observe morphological features of transverse views of swollen fibers refined under low and high intensity, but also to investigate the sequence of fiber wall delamination and fiber wall breakage. From the CLSM images, increasing the specific energy or refining decreased the degree of fiber collapse, fiber cross-sectional area, fiber wall thickness and lumen area. High intensity refining produced more external fibrillation.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.45 no.5
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• pp.56-63
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• 2013

In this study, paper mill applicability of two kinds of cotton pulps which have different initial freeness, fiber length and intrinsic fiber strength were investigated. Basic properties such as CED viscosity, fiber length, and crystallinity of major two kinds of cotton pulps were analyzed, and beatability of cotton pulps and physical properties of handsheet made from two kinds of cotton pulps were compared. Laboratory beating was performed at different refining conditions such as refining loads and freenesses. Relationship between beating degree and physical properties of handsheet were compared to seek optimum condition of refining for different cotton pulps application to paper mill.

• Journal of the Korean institute of surface engineering
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• v.27 no.5
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• pp.292-302
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• 1994

Alloy deposits of 80Sn-20Pb, electroplated on Cu-based leadframe alloy from an organic sulfonate bath were aged at $150^{\circ}C$ to form intermetallic phases between substrate and deposit, and effects of the deposit morphology, influenced by deposition conditions, on the fracture resistance of the 80Sn-20Pb deposit aged at $150^{\circ}C$ were examined. The growth rate of intermetallic compound layer on aging depended on the microstructure of deposit ; it was fastest in deposit formed using pulse current in bath without grain refining additive, but slowest in deposit formed using dc current in bath containing grain refining additive in spite of similar structure with equivalent grain size. The grain refining additive incorporated in electrodeposit appears to inhibit diffusion of atoms on aging, resulting in slow growth of intermetallic layer in the thickness direction but substantial growth in the lateral one. Density of surface cracks that were occurring when samples were subjected to the $90^{\circ}$-bending test increased with increasing the thickness of intermatallic layer on aging. For the same aged samples, the surface crack density of the sample electrodeposited from a bath containing the grain refining additive was the least due to the inhibiting effect of the additive incorporated into the deposit during electrolysis on atomic diffusion.

• Applied Biological Chemistry
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• v.40 no.4
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• pp.294-300
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• 1997

As a part of basic investigation for utilizing by-products derived from marine food processing more effectively as a food source, refining of viscera oil of squid caught off Newzealand were investigated. In the process of refining, degumming with 3% of phosphoric acid at $60^{\circ}C$ for 30 min was effective in removing phosphatides, and optimal condition to neutralize was treating with 0.6% excess of 20% sodium hydroxide solution at $80^{\circ}C$ for 20 min. Bleaching was optimized by adding 10% activated clay and treating for $100^{\circ}C$ for 20 min under vacuum, and deodorizing was done by steam destillation at $180^{\circ}C$ for 60 min under 4 torr of vacuum. Acid value, peroxide value and chromaticity of refined squid viscera oil were 0.20, 0.8 meq/kg and 0.019, respectively. The ratio of polyenoic acid composition to saturated acid composition of refined squid viscera oil was 1.28 and its major fatty acids were 16 : 0, 18 : In-9, 20 : 5n-3 and 22 : 6n-3.

• Resources Recycling
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• v.27 no.6
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• pp.38-43
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• 2018

In this study, using electro-refining process and methane gas reduction, we performed studying the recovery of tin with high purity from waste tin oxide had used as a electrode rod of ceramic furnace which occurred during glass production process. We recovered the crude tin of 99% purity from a methane gas reduction process and controlled a little amount of impurities. When the electrolytic refining condition was a current density of $60A/dm^2$ and the sulfuric acid concentration of 0.75 mol, 96.8% of recovered tin (99.979% of purity) were recovered during the electrolytic refining. We confirmed that toxic impurities such as Pb, Sb included in electrode rod. could be controlled.

• Journal of the Korean Society of Food Science and Nutrition
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• v.21 no.2
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• pp.175-180
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• 1992

For the effective utilizing of polyunsaturated lipids in filefish viscera wasted from marine manufactory the conditions of degumming, deacidification, decoloring and deodorization for the processing of refined viscera oil were investigated. In the process of refining degumming with 20$m\ell$ of 4% oxalic acid per 100$m\ell$ of crude filefish viscera oil resulted in the lowest residual phosphorus content as 115.8 ppm and optimal condition to neutralize the filefish viscera oil was treating for 30min at 60$^{\circ}C$ with 0.5% excess of 4M sodium hydroxide solution. Decoloring was optimized by adding 10% bleaching earth and treating for 20min at 60$^{\circ}C$ under vacuum, and deodorizing was done by steam distillation at 180$^{\circ}C$ under 4 torr of vacuum.

• Journal of Korea Foundry Society
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• v.18 no.5
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• pp.474-480
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• 1998

Microstructural characteristics of semi-solid state processed hypereutectic Al-Si alloys have been investigated. Main concern of the present study is to investigate the effects of P and Sr addition on the size and morphology change of the primary Si particles. Refinement of the primary Si particles was observed with the addition of P and Sr at the early stage of semi-solid state processing, but such a refining effects became negligible resulting in Si particles with a near-spherical morphology with continuous stirring. This implies that the microstructural transformation mechanism became more dependent to stirring effects than to the alloying effects during semi-solid state processing. Brittle fracture and agglomeration were proposed as the mechanisms for microstructural alterations during semi-solid state processing.

• Journal of Korea Foundry Society
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• v.23 no.2
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• pp.69-76
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• 2003

The present work was undertaken to investigate the mutual effect of the individual melt treatment commonly applied in aluminum foundries such as grain refining, modification, degassing and filtration on the microstructures and the mechanical properties. A357 alloys were fabricated through various melt treatments such as degassing by gas bubbling filtration, modification via the addition of Al-Sr master alloy, grain refining through the addition of Al-Ti-B master alloy and filtration before pouring of the melt. Each melt treatment was performed at its optimum condition reported in the literatures. The effects of each melt treatment and their interactions on the microstructures and mechanical properties of A357 alloy were examined.