• Journal of Adhesion and Interface
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• v.9 no.4
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• pp.12-16
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• 2008

Hot-melt adhesive was solid phase in room temperature as 100% solid contents. So it has advantage which attach to substrate with the low pressure heat, fast adhesion speed and environment friendly. In this study, We studied about the effect of a kind of SBS resin and petroleum resin as a tackifier resin and their ratio for hot-melt adhesive on properties. The styrene and $C_9$ resin contents in hot-melt adhesive was increased with increasing viscosity, tensile strength, peel strength and thermal resistance.

• Journal of the Korean Ceramic Society
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• v.27 no.6
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• pp.713-720
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• 1990

The effects of substituting Zn+2 for Ni+2 ion on dielectric and piezoelectric prooperties of Pb(Zn1/3Nb2/3)O3-Pb(Ni1/3Nb2/3)O3-PZT ceramics were investigated. With increasing Zn2+ contents the tetragonality was appreciably enhanced and the grain size decreased. Both Curie temperature and thermal stability were increased with increase in Zn2+ contents since the Zn+2 partial substition for Ni+2 could form solid solution in almost range of the composition investigated. Piezoelectric prooperties showed the maximum($\varepsilon$ T/$\varepsilon$0=5014, kp=0.56, d31=250$\times$10-12m/V) in 4.5Pb(Zn1//3Nb2/3)O3-40.5Pb(Ni1/3Nb2/3)O3-55PZT composition sintered at 125$0^{\circ}C$ and then decreased again due to the phase boundary movement for tetragonal phase of the solid solution of Zn2+ amount.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.04a
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• pp.375-378
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• 2011

The combustion characteristics of fuel-rich gas generator which could be adopted to Ducted Rocket propulsion system is investigated. The gas generator is designed considering the design requirements of propulsion system then solid fuel, which is developed by reducing the contents of oxidizer and increasing the contents of metallic solid particle, is loaded in the manufactured gas generator. The results of combustion test shows the necessity of the special analysis tool for estimating the gas generator performance where multi-phase flow of fuel-rich gas exists.

• Journal of the Korean Applied Science and Technology
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• v.35 no.4
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• pp.995-1002
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• 2018

Hairy root culture of ginseng is industrially prospected because the cultivation period of ginseng is relatively long. In this study, the effect of medium concentration and sucrose concentration on hairy root culture of ginseng was evaluated. The optimization of ginseng hairy roots transformed by Agrobacterium rhizogene were performed liquid medium. The MS(Murashinge & Skoog basal medium) concentration was selected with 1/2 strength MS and the optimal sucrose concentration was determined at 2-3%(w/v). At the optimum culture condition, The yield (the ratio of weight of grown hairy root cultures to weight of fresh ginseng hairy roots) and production rate of ginseng root were 19.42 times and 5.73 g/l-day. The major ginsenosides were Rb group, Re and Rg1. The produced total ginsenoside content in the solid medium was 9.87 (mg/g) and increased 1.34 times in the liquid medium (13.23 mg/g). In solid culture, the contents of ginsenosides Rb, Re and Rg1 were 2.14, 3.65 and 1.87 mg/g, respectively. In liquid culture, the contents of ginsenosides Rb, Re and Rg1 were 3.54, 4.12 and 2.63 mg/g, respectively.

• Journal of the Korean Wood Science and Technology
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• v.49 no.2
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• pp.169-180
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• 2021

Inherent crystalline domains present in low formaldehyde to urea (F/U) molar ratio urea-formaldehyde (UF) resins are responsible for their poor adhesion in wood-based composite panels. To modify the crystallinity of low molar ratio (LMR) UF resins, this study investigates the additional effect of cellulose nanomaterials (CNMs), such as cellulose microfibrils (CMFs), cellulose nanofibrils (CNFs), and TEMPO-oxidized CNFs (TEMPO-CNFs) on the crystallinity of modified LMR UF resins. First, two modification methods (post-mixing and in situ) were compared for modified LMR UF resins with TEMPO-CNFs. The modified UF resins with TEMPO-CNFs decreased the nonvolatile solid contents, while increasing the viscosity and gel time. However, the in situ modification of UF resins with TEMPO-CNFs showed lower crystallinity than that of post-mixing. Then, the in situ method was compared for all CNMs to modify LMR UF resins. The modified UF resins with CMFs using the in situ method increased nonvolatile solid contents and viscosity but decreased the gel time. The crystallinity of UF resins modified with TEMPO-CNFs was the lowest even though the crystalline domains were not significantly changed for all modified UF resins. These results suggest that these CNMs should be modified to prevent the formation of crystalline domains in LMR UF resins.

• Bulletin of the Korean Chemical Society
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• v.27 no.6
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• pp.909-917
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• 2006

2,2-Dimethyl-3,4-dialkoxy-substituted 6-aminobenzopyran analogues (eg., 7 and 8) were identified as prolyl 4-hydroxylase inhibitors via a screening process using HSC-T6 and LI 90 cells that express an immortalized rat hepatic stellate cell line and as part of a test of the type I collagen contents employing the ELISA method. A subsequent lead optimization effort based on solid-phase parallel synthesis led to the identification of 2,2-dimethyl-3,4-dialkoxy-substituted 6-aminobenzopyrans as potent inhibitors of prolyl 4-hydroxylase.

• Journal of Pharmaceutical Investigation
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• v.33 no.1
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• pp.7-14
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• 2003

The PVP-based solid dispersion systems (SDs) containing lovastatin (LOS) and solubilizers (sodium lauryl sulfate, tween 80 and oleic acid) were prepared to enhance dissolution rate of practically water insoluble LOS using solvent evaporation method. Two different organic cosolvents either acetone/ethanol or acetonitrile/ethanol were used for the preparation of SDs. The LOS contents were highly decreased when acetone/ethanol cosolvents were used. The decrease of LOS contents was not caused by acetonitrile or acetone, based on HPLC data. The surface morphology as investigated by scanning electron microscope (SEM) and angle of repose as an index of flowability of SDs were highly dependent on the type and amount of solubilizers used. Based on differential scanning calorimetry (DSC) and X-ray powder diffraction data, the SDs made crystalline LOS into amorphous structure or partially eutectic mixtures. The simultaneous use of the solubilizers in SDs was also useful to increase dissolution rate of LOS in gastric or intestinal fluid. The SDs containing solubilizers reached 76% and 60% in gastric and intestinal fluid, respectively but the commercial tablet gave only less than 4%. These solubilizers in SDs could be also applicable for enhancing dissolution and bioavailability of poorly water-soluble drugs.

• Journal of Environmental Health Sciences
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• v.7 no.2
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• pp.73-87
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• 1981

Generation of Solid Wastes grew rapidly with the increase of living standard of the people in Korea recently and their composition was more complicate. The weight of Solid wastes generated in Seoul into year of 1979 was about 420 million tons which required 1.5 million $m^2$ of burial land and daily generation for person was 1.6kg. The Composition of more than 80% ash contents was suitable for sanitary landfill but recently ash was decreasing while paper, synthetic materials, glass etc, increasing and alternative method had to be found to dispose the wastes properly. Weight and Composition of Wastes by season and living standard were surveyed for one year from June 1980 to May 1981 in Seoul. Disposal mathods by waste composition was studied. Results were summarized as follows: 1) Each component stored separately at generation point was to be collected and to be reused or disposed by public organization or private company. Some incentives have to be arranged. 2) Wastes collected from household were transfeted to about 420 temporally storing places and transported to two dumping areas by about 700, 4-8 tons trucks which droped litters on the streets. Large dumping lots should constructed along the western coasts and the wastes would be transported through big container trucks or trains to the lots. 3) Ash contents decreased to 40-70% while garbage, synthetic materials, paper increased and they are two to three times in summer of those in winter. Ash in affluent residential areas is less than 50% of whole wastes while that in poor apartment and residential areas is 60-70%. 4) Large dumping places should be constructed along the western coasts which are not far from Seoul because no suitalbe lands are available, and proper leakage protection arrangements should be made.

• The Journal of the Korea Contents Association
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• v.10 no.4
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• pp.106-114
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• 2010

Mesh parameterization is the process of finding one-to-one mapping between an input mesh and a parametric domain. It has been considered as a fundamental tool for digital geometric processing which is required to develop several applications of digital geometries. In this paper, we propose a novel 3D volume parameterization by means that a harmonic mapping is established between a 3D volume mesh and a unit solid cube. To do that, we firstly partition the boundary of the given 3D volume mesh into the six different rectangular patches whose adjacencies are topologically identical to those of a surface cube. Based on the partitioning result, we compute the boundary condition as a precondition for computing a volume mesh parameterization. Finally, the volume mesh parameterization with a low-distortion can be accomplished by performing a harmonic mapping, which minimizes the harmonic energy, with satisfying the boundary condition. Experimental results show that our method is efficient enough to compute 3D volume mesh parameterization for several models, each of whose topology is identical to a solid sphere.

• Korean Journal of Food Science and Technology
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• v.16 no.2
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• pp.165-168
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• 1984

The three kinds of Kochujang were prepared with liquid koji equivalent to 30, 50 and 70% of brewing water and the composition of fatty acid and alcohols in the Kochujang aged at $25^{\circ}C$ for 3 months were compared with solid koji Kochujang. Palmitic, oleic and linoleic acid were found in all Kochujangs; but myristic, stearic and linolenic acid were detected in only the 50 and 70% liquid koji group. The predominant fatty acid of all Kochujang was linoleic acid, followed by oleic and palmitic acid. The total percentage of linoleic acid in the Kochujang was 58.47-83.39%. Linolenic, myristic and stearic acid were less than 3%. Ethyl, iso-butyl and iso-amyl alcohol were detected from all kinds of Kochujang. Iso-propyl alcohol was found in the Kochujang prepared from solid koji and 30% liquid koji. The contents of iso-butyl and iso-amyl alcohol were high in solid koji Kochujang and 50% liquid koji Kochujang. There were no significant difference in the contents of ethyl alcohol among tested Kochujangs.