• The Korean Journal of Food And Nutrition
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• v.8 no.4
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• pp.335-343
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• 1995

In order to enhance the utility of alaska-pollack, the optimum conditions for the preparation of pronase hydrolysate. The optimum temperature and pH for the hydrolysis of alaska-pollack by pronase were 4$0^{\circ}C$ and pH 7.0. The reaction time and enzyme concentration were 4 hr and 1,000 units per g of substrate. Under the above optimum conditions alaska-pollack was hydrolysed by pronase yielding a hydrolytic degree of about 89eye. The bitterness and hyrophobicity of pronase hydrolysate were decreased with increasing reaction time. Hydrophobic amino acids(Tyr, Met, Ala, flu, Leu, and Phe) were increased for 2 hr, but fur thor hydrolysis was showed decrease of hydrophobic amino acids content. Palatable amino acids (Asp, Glu, Pro, Ser, Thr and Gly) were increased with hydrolysis time.

• Textile Coloration and Finishing
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• v.17 no.4 s.83
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• pp.1-6
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• 2005

We studied the degree of variety of indigo for the electrochemical redox reaction in addition of reducing agent and the electrokinetic parameters. The electrokinetic parameters such asthe number of electron and the exchange rate constant were obtained by cyclic voltammetry. With increasing scan rate, the reduction currents of indigo were increased and the reduction potentials were shifted to the negative direction. As the results, the reduction processes of the indigo were proceeding to totally irreversible and diffusion controlled reaction. Also, exchange rate constant ($k^0$) and diffusion coefficient ($D_0$) of indigo were decreased by increasing concentration of reducing agent. We found that the less concentration, the more easily diffused and electron transferred and the product was more stable.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2000.11a
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• pp.11-12
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• 2000

Non-stoichiometric ceramics of $Ni_{x}ZnO_{1-x}Fe_{2}O_{4}$ were prepared by self-propagating high temperature synthesis reaction with various processing conditions and their stoichometric numbers were determined by neutron diffraction. The neutron diffraction patterns were measured at room temperature using monochromatic neutrons with a wave length of 0.18339 nm from a Ge(331) mocochromator at a 90 degree take off angle. The Rietveld refinement of each pattern converged to good agreement (x2=1.88-2.24). The neutron diffraction analysis revealed the final stoichiometries of the ferrites were $Ni_{0.38}Zn_{0.62}Fe_{2}O_{4}$ and $Ni_{0.33}Zn_{0.67}Fe_{2}O_{4]$, respectively. This supports that final stoichiometric number of the self-propagating high temperature synthesis product can be controlled by the processing parameters during the combustion reaction.

• Transactions of Materials Processing
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• v.21 no.2
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• pp.101-106
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• 2012

Generally, rapid cure reaction of LED encapsulation silicone resin causes serious defects in cured resin products such as warpage, residual bubbles, and reduced wettablility. In order to prevent residual bubbles in silicone resin, the step cure process was examined in the present paper. Three kinds of step cure processes were applied, and bubble-free phenomenon was observed. Most of the bubbles were removed under $70^{\circ}C$, the minimum temperature for activating cure reaction. In addition, degree of cure(DOC) and temperature distribution were predicted by using FEM analysis of heat transfer. It was concluded that maintaining cure temperature which provide a DOC under 0.5~0.6 effectively reduces residual bubbles.

• Textile Coloration and Finishing
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• v.7 no.1
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• pp.65-71
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• 1995

Wool yarns were treated in dimethylformamide solutions containing various concentrations of three dibasic acid anhydrides : succinic, itaconic, and phthalic anhydrides in various conditions. The structural aspects of these dibasic acid anhydrides are different : the succinic, itaconic, and phthalic acid anhydrides have saturated aliphatic etylene, unsaturated aliphatic vinyl and aromatic phenyl groups, respectively. The reaction mechanism of the acylation of wool keratin and some resction conditions were invastigated. And the results are as follows. 1. The N-acylation and formation of free carboxyl group were dominant rather than the O-acylation cross-linked on the side chain of polypeptide. The acylation of wool keratin is easier than that of silk fibroin. 2. The higher molecular weight, steric hinderance and resonance caused lower acylating reactivity. By the determination of acyl contents for acylated keratin, it was rerealed that the degree of acylation was succinic acid anhydride > itaconic acid anhhydride > phthalic acid anhydride.

• Journal of the Korean Applied Science and Technology
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• v.37 no.5
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• pp.1248-1256
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• 2020

In this study, the polyurethane resin was synthesized by applying PTMG and DMBA of different composition ratios for the synthesis of water-dispersible polyurethane used in wound coating resin. The varying properties of the synthesized water-dispersible polyurethane were measured through tensile strength, elongation, and abrasion resistance analysis. As for the tensile strength measurement result according to the PTMG content, the sample with the highest reaction molar ratio was measured as 1.08 kgf/mm2 and the elongation was measured as 520%. As for the tensile strength result according to the DMBA content, the sample with the highest reaction molar ratio was measured as 0.51 kgf/mm2, and the elongation was measured as 435%. The degree of surface destruction by the abrasion resistance measurement was visually confirmed through SEM.

• Journal of Powder Materials
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• v.13 no.6 s.59
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• pp.432-438
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• 2006

Aluminum nitride (AlN) nanopowders with low degree of agglomeration and uniform particle size were synthesized by carbothermal reduction of alumina and subsequent direct nitridization. Boehmite powder was homogeneously admixed with carbon black nanopowders by ball milling. The powder mixture was treated under ammonia atmosphere to synthesize AlN powder at lour temperature. The effect of process variables such as boehmite/carbon black powder ratio, reaction temperature and reaction time on the synthesis of AlN nanopowder was investigated.

• Journal of Food Hygiene and Safety
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• v.14 no.1
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• pp.84-89
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• 1999

Octenylscuccinated corn starches prepared by reaction of corn starch with 1-octenylsuccinic anhydride(OSAn) and their degree of substitution (DS), reaction efficiency(RE), residual octenylsuccinic acid (OSA), and physicochemical properties were compared with those of the native corn starch. DS increased with increase of OSAn and RE was much nearly the same regardless of increased of OSAn. The content of residual of residual OSA was significantly lower than that of regulation of food additives. And as washing frequency of dispersion of the reactant was increased, the content of residual OSA of octenylsuccinated starch was decreased. Raid Visco-Analyzer initial pasting temperature and setback of octenylsuccinated starches decreased whereas peak viscosity and breakdown increased. When DS of octenylsuccinated starches increased, temperature of initial gelatinization of octenylscuccinated starches drastically decreased. The octenylsuccinated starches also formed clearer pastes. The solubility was much nearly the same regardless of increase of DS at 7$0^{\circ}C$ but the swelling power increased 1.2~1.7 times higher than that of native corn starch at 7$0^{\circ}C$. The water binding capacity of octenylsuccinated starches also decreased.

• Proceedings of the KIEE Conference
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• 2001.04a
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• pp.87-89
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• 2001

The unbalanced reciprocation force due to armature reaction field decreases the advantage of moving coil linear motor, such as a high degree of linearity and controllability in the force and motion control. This paper firstly describes the coil inductance, and the unbalanced force. Secondly, the dynamic simulation algorithm considering the armature reaction effect and variable inductance is proposed. Thirdly, the control algorithm is proposed to reciprocate a load without mechanical spring at the required stroke and position. Finally, the validity of the proposed algorithm is confirmed by experiments.

• Journal of the Korean Ceramic Society
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• v.33 no.1
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• pp.41-48
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• 1996

Self-propagating High-temperature Synthesis of Ti+N system has been investigated using the cylindrical high pressure reactor. The nitrogen pressure was varied from 40 to 80 atmosphere and TiNx(x=0.55) powder produced by SHS process was used as a diluent in order to control the reaction. Both the velocity of surface reaction and the ratio of TiN synthesis increased with increasing the nitrogen pressure. As the amount of diluent increases the degree of conversion to titanium nitride increases. Homogenious TiN powder was obtained in the composition 50Ti+50TiN0.94(diluent)