• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.32 no.4
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• pp.58-65
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• 2000

Use of a pectinase during preparing handmade papers from bast fiber of paper mulberry(Broussonetia kazinoki Sieb.) was investigated in order to decrease cooking chemicals and environmental pollution. For this purpose, four kinds of commercial pectinases, Rapidase LIQ(RLP), Rapidase Press(RP), Rapidase C80L Max(RCM) and Pectinase SS Kyowa(PSK) were used. And the durability of handmade papers before and after pectinase treatment was determined. RP and PSK had higher pectinase activity ad lower cellulase activity. The bast fiber was not defibered when pectinase was used. In order to increase the efficiency of enzymes, the bast fiber were treated ammonium oxalate(AO) or $K_2CO_3$under mild conditions. The AO pretreatment with those produced by $K_2CO_3$. The RP treated pulps after mild $K_2CO_3$cooking of the bast fiber were defibrated more easily than untreated pulp. The handmade paper prepared with the RP treated pulps after mild $K_2CO_3$cooking has good strength properties such as breaking length and folding endurance. Also, it has higher durability on heat aging, though its brightness was slightly lower than that of untreated paper.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.46 no.6
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• pp.8-15
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• 2014

The increase of wet web solid content in wet pressing will save drying energy greatly. We applied wood flours as spacers to increase the old corrugated container (OCC) solid contents in wet pressing. The mixed furnish of OCC and wood flours of 3-5% (wt/wt) increased bulk and drainage rate, and by increasing wet pressing pressure, its solid content started to be higher than 100% OCC furnish at more than 50% solid content level. Addition of cationic starch and drainage aid to the mixed furnish increased solid content further up to around 2%. Cationic starch addition compensated or exceeded the loss of tensile and compressive strength caused by the addition of wood flour, but drainage aid did not. Cationic starch also improved the stretch of the OCC, which could mitigate cracking at folding in boxboard.

• Journal of the Korean Society of Food Culture
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• v.31 no.4
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• pp.357-363
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• 2016

The principal objective of this study was to evaluate the utilization of fish paste with added Capsosiphon fulvescens powder were 0, 3, 5, and 7%. The moisture, crude protein, crude lipid, crude ash and carbohydrate contents of the used Capsosiphon fulvescens powder were 8.5, 33.2% 1.1, 9.6, and 47.6%, respectively. For the Hunter color values, the L, a values of the fish paste decreased with increasing concentrations of Capsosiphon fulvescens powder. The b values of the fish paste appreciation with increasing concentrations of Capsosiphon fulvescens powder. And the folding test which represent the flexibility of the fish paste, all test samples showed AA. In the texture meter test, the hardness, strength, cohesiveness, and springiness increased according to increasing concentrations of Capsosiphon fulvescens powder. However, the gumminess and brittleness of the fish paste reduced by the addition of Capsosiphon fulvescens powder. In the sensory evaluation, color and taste of the fish paste were preferred 5% Capsosiphon fulvescens powder and the fish paste prepared with 5% Capsosiphon fulvescens powder were preferred over other fish pastes. These results suggest that Capsosiphon fulvescens powder can be applied to fish paste for the purpose of high quality and functionality.

• Proceeding of EDISON Challenge
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• 2014.03a
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• pp.103-113
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• 2014

Hydrophobicity is the key concept to understand the role of water in protein folding, protein self-assembly, and protein-ligand interaction. Conventionally, hydrophobicity of amino acids in a protein has been argued based on hydrophobicity scales determined for individual free amino acids, assuming that those scales are unaltered when amino acids are embedded in a protein. Here, we investigate how the hydrophobicity of constituent amino acids depends on the protein context, in particular, on the total charge and secondary structures of a protein. To this end, we compute and analyze the hydration free energy - free energy change upon hydration quantifying the hydrophobicity - of three short proteins based on the integral-equation theory of liquids. We find that the hydration free energy of charged amino acids is significantly affected by the protein total charge and exhibits contrasting behavior depending on the protein net charge being positive or negative. We also observe that amino acids in the central ${\beta}$-strand sandwiched by ${\beta}$-sheets display more enhanced hydrophobicity than free amino acids, whereas those in the ${\alpha}$-helix do not clearly show such a tendency. Our results provide novel insights into the hydrophobicity of amino acids, and will be valuable for rationalizing and predicting the strength of water-mediated interaction involved in the biological activity of proteins.

• Proceeding of EDISON Challenge
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• 2016.03a
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• pp.163-166
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• 2016

Hydrophobicity is the key concept to understand the water plays in protein folding, protein aggregation, and protein-protein interaction. Traditionally, the hydrophobicity of protein is defined based on the scales of the hydrophobicity of residue, assuming that the hydrophobicity of free amino acids is maintained. Here, we explore how the hydrophobicity of constituting amino acids in protein rely on the protein context, in particular, on the total charge and secondary structures of a protein. To this end, we calculate and investigate the hydration free energy of three short proteins based on the integral-equation theory of liquids. We find that the hydration free energy of charged amino acids is significantly affected by the protein total charge and exhibits contrasting behavior depending on the protein total charge being positive or negative. We also observe that amino acids in the ${\beta}-sheets$ display more enhanced the hydrophobicity than amino acids in the loop, whereas those in the ${\alpha}-helix$ do not clearly show such a tendency. And the salt-bridge forming amino acids also exhibit increase of the hydrophobicity than that with no salt bridge. Our results provide novel insights into the hydrophobicity of amino acids, and will be valuable for rationalizing and predicting the strength of water-mediated interaction involved in the biological activity of proteins.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.46 no.5
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• pp.88-97
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• 2014

For the purpose of reproduction of traditional gold thread, the artifact investigation was organized for 70 cases (109 pieces) of relics from Korea, China and Japan. In most cases, the main backside material of gold thread from Korea was the bast fibers from paper mulberry. In this study, the optimum sheet-making of Hanji for gold thread reproduction was tried by controlling several process factors of Hanji such as the cooking and beating time of paper mulberry fibers, the number of sheet-making ply, and converting method (Dochim). Tensile index, folding endurance and compressive strength of Hanji showed differences according to the correlation between cooking and beating time, and application of converting method (Dochim), while bending stiffness fell with decrease of thickness. These results can be applied to consider manufacturing factors to make Hanji for the production of gold thread.

• Journal of the Korean Wood Science and Technology
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• v.47 no.5
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• pp.617-632
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• 2019

This study aimed to investigate the anatomical structure and fiber quality of four lesser-used wood species namely Benuang (O. sumatrana), Duabanga (D. moluccana), Pisang Merah (H. hellwigii), and Terap (A. odoratissimus). This study evaluated its suitability for raw material in pulp and paper manufacturing. The anatomical structure was observed macro- and microscopically. Macroscopic structures were observed directly to the wood samples, while microscopic characteristics were observed through microtome specimens. Fiber dimension was measured through macerated specimens and fiber quality was analyzed following the Rachman and Siagian's method. Results showed that these four timber species have similarity in the indistinct growth ring, diffuse porous in a radial pattern, rounded solitary vessel outline, 1 to 3 cells of ray width, deposits within the rays, fiber length, and cell wall thickness. Differences were found on vessel diameter, vessel grouping, vessel frequency, tyloses existence, type of axial parenchyma, and ray height. Based on fiber length and its derived values, the wood fibers of all species studied are suitable for pulp and paper manufacturing. They belong to the II quality class. The produced pulp and paper would have good quality, especially in tensile, folding, and tear strength. To promote their utilization, silviculture aspect of these four species has to be well understood.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.52 no.6
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• pp.562-570
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• 2019

To develop natural-tasting fish paste from the pufferfish Lagocephalus wheeleri, steamed pufferfish paste (SPP) was prepared and its optimal processing conditions, quality metrics, and shelf-life characteristics were examined. SPP was produced by thawing golden threadfin Nemipterus virgatus surimi (FA grade), then adding 10% unwashed pufferfish surimi (PS), 1.5% salt, 8.0% wheat starch, 0.25% calcium carbonate, 0.25% sugar, 0.75% sorbitol, 0.25% polyphosphate, and 12.0% pufferfish hot-water extract (Brix 10°). The meat was ground with a Stephan mixer, molded at low temperature (18℃, 10 h), vacuum packed in a laminated plastic film bag, heat treated with hot water (95℃, 50 min), and cooled. As the amount of PS added increased, the whiteness, gel strength, and shear strength of the SPP decreased slightly. However, the SPP folding test showed no deterioration in the texture. In the sensory evaluation, the SPP received a higher rating for taste, smell, and overall taste than commercial Japanese pufferfish Kamaboko. The total amino acid content of the SPP was 10,262.6 mg/100 g; the major amino acids were aspartic acid, glutamic acid, alanine, valine, leucine, lysine, and arginine. The free amino acid content was 133.0 mg/100 g; the major amino acids were taurine, glutamic acid, glycine, alanine, cystine, and lysine.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.33 no.4
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• pp.15-20
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• 2001

The function of the moisture-proof paper is to prevent moisture from adsorbing into the packed goods. Water-vapor transmission rate of the moisture-proof paper should be less than 100g/$m^2$.24hr and the optimum rate would be less than 50g/$m^2$.24hr. In general the moisture-proof paper has been made by laminating polyethylene or polypropylene on top of the base paper. However this kind of moisture-proof paper has a problem in recycling so that it brings about environmental pollution. In general the moisture-proof paper has been made by laminating polyethylene or polypropylene on top of the base paper. However this kind of moisture-proof paper has a problem in recycling so that it brings about environmental pollution. The purpose of this paper was to make moisture-proof paper using the mixture of SB latex and wax emulsion which was recyclable and environmentally friendly. Water vapor transmission rate showed less than 50g/$m^2$.24hr in mixture ratio of 85:15, 87:13, 90:10. Especially the mixture ratio of 87:13 showed the most favorable water-vapor transmission rate. However, the moisture-proof layer was destroyed slightly by folding in packing. It has been observed that there was no close relationship between water-vapor transmission rate of the moisture-proof paper and grammage of the base paper, but the density of base paper had influenced on water vapor transmission rate. It was also observed that the moisture-proof paper could be recycled. The moisture-proof paper was similar to base paper in degree of the pulping, and there was no significant difference in dispersion between moisture-proof paper and base paper. Most of wax particles which caused the spots during drying process could be removed by flotation process. Tensile strength and tear strength of both moisture-proof paper and base paper after pulping were measured to examine the fiber bonding, and no significant difference in physical properties was observed.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.35 no.4
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• pp.8-16
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• 2003

The objective of this study was to investigate the potential application of the separated refining system in the papermaking process using cotton pulps. The cotton staple and linter fibers were expected to show a great difference in their refining responses due to their morphological and physical differences. Experiments were conducted to examine the differences in flocculation tendency, CED viscosity, fiber length, handsheet properties and the SEM surface images between staple and linter fibers at a given refining degree. These fibers were also subjected to separated refining in a laboratory-scale beater and in a mill-scale refiner as well. The effect of the separated refining on the refining rates and papermaking properties were evaluated. Results obtained are summarized as follows: 1. Fiber flocculation tendency of cotton staple was estimated to be significantly greater than that of linter fibers; 2. The staple fibers showed higher cellulose DP, longer fiber length and higher sheet strength at a given refining degree compared to linter fibers, but remarkably slower refining rate was observed; 3. The separated refining system exhibited a significant increase in sheet strengths, especiauy in folding endurance, with an increase in the fibrillation on the surface of staple fibers, but slightly lower or comparable fiber length after refining to the mixed refining system; 4. Similar results were also obtained from the machine trial in which about 7-8％ energy saving effects were achived in the separated refining system. On the basis of the results observed in this study, it was concluded that a significant increase in paper strength and a substantial reduction in refining energy consumption could be achieved using the separated refining system for the cotton staple and linter fiber stock refining.