• Elastomers and Composites
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• v.47 no.4
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• pp.318-328
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• 2012

In this study, the one-component curable polyurethane resin was manufactured using blocked isocyanate and hybrid technology. To prepare the one-component curable hybrid polyurethane, silica hybrids including hydroxyl group was synthesized, and the size, shape and distribution of hybrid particle in polyurethane resin were confirmed. Then the dissociation property, mechanical property and molding property of blocked isocyanate were investigated. The dissociation property of blocked isocyanate in one-component curable polyurethane became better as the heating temperature and treatment time increased. The synthesized silica hybrid had spherical appearance and size of 23~27 nm in diameter, and it was observed that the hybrid particles were homogeneously distributed in polyurethane structure. In the case of hybrid polyurethane, the mechanical property, anti-abrasion and thermal property were higher than those of general polyurethane, and it was observed that the mechanical property was maintained when the plasticizer was introduced.

• Food Science and Preservation
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• v.10 no.3
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• pp.401-405
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• 2003

The antibiotic and antioxidant effect of botanical antimicrobial agent-citrus product(BAAC) prepared from citrus fruits were investigated by using fishmeats made from pollack and ascidian fillet. We inoculated Salmonella typhi into fishmeats that were aferwards treated with BAAC varying the concentration level (50-500ppm) including the control not-treated with BAAC. While specimens were stored at 5$^{\circ}C$ for designated period, we measured changes of total number of bacteria, peroxide level and textural properties. In addition, we performed organoleptic examination, focusing on appearance, texture and odor for fishmeats treated with BAAC and stored for designated period. For pollack and ascidian fishmeats, the initial total number of bacteria were 3.7${\times}$l0$^4$CFU/g and 7.5${\times}$l0$^4$CFU/g, respectively. After they were treated with 250 ppm of BAAC solution and stored for 5 days at 5$^{\circ}C$, the figures reduced to 2.5${\times}$l0CFU/g and 8.4${\times}$10CFU/g. No bacteria were found in fishmeats treated with above 500 ppm of BAAC, which remarkably proved antibiotic effect of BAAC solution. Furthermore, all the BAAC-treated specimens exhibited notable antioxidant effect. Fishmeats which were previously treated with 500 ppm of BAAC solution and stored for 30 days at 5$^{\circ}C$, showed the lower peroxide level of 16.5 meq/kg than 68.9 meq/kg in the control of pollack and 21.2 meq/kg than 80.7 meq/kg in the control of ascidian. In the results of texture and organoleptic evaluation we could also observe good effects of BAAC on maintaining the freshness of fisher products.

• Korean Journal of Food Science and Technology
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• v.16 no.2
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• pp.182-184
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• 1984

In order to develop the storage method of pine agaric by irradiation, pine agarics irradiated with 1,2 and 2.5 kGy were stored in natural low temperature storage room ($15{\pm}2^{\circ}C$, RH: $80{\pm}5%$) and the physicochemical properties were investigated during the 15 days of storage. Veil opening rate of pine agaric was 97% after 7 days storage in control, whereas only 5% in 2-2.5 kGy irradiated groups. Rotting rate after 7 days storage were 28% in control,5-8% in 2-2.5 kGy irradiated groups. In comparison of weight loss, texture and appearance.2-2.5 kGy irradiated groups were better than control. Chemical composition of pine agaric was not remarkably changed by the irradiation and storage period except a slight increase in reducing sugar and a decrease in ascorbic acid by the increase of irradiation dose.

• Korean Journal of Food Science and Technology
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• v.44 no.1
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• pp.28-33
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• 2012

The effect of puffing conditions on the physical properties and sensory evaluations of a puffed snack (ppeongtuigi) made of purple sweet potato flour was investigated. The snacks consisted of coated artificial rice with purple sweet potato flour with water, tempered to 7%, 9% and 11% moisture. The coated material was puffed at 236, 241, or $246^{\circ}C$ for 4, 5, or 6 s. The $L^*$ value decreased as the heating time increased. The $a^*$ and $b^*$ values, specific volume, and hardness increased with increasing heating temperature and heating time. Puffed snacks produced under conditions of higher moisture (7%), higher heating temperature ($246^{\circ}C$), or longer heating time (5 s) showed high scores for appearance, color, taste, and overall acceptability in sensory evaluations.

• Korean Journal of Materials Research
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• v.8 no.10
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• pp.898-904
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• 1998

Ni-W alloys containing 10 to 50wt% W were prepared by electrodeposition. Tungsten content in the alloy increased with current density. X-ray diffraction analysis revealed that the alloy was crystalline phase when deposited at current densities lower than 50mA/${cm}^2$. Their crystal structure transformed to amorphous at higher current densities. In terms of tungsten content, the crystal -+ amorphous transition occurred at 40-46wt% which was identified by the 3 fold increase in the width of a diffraction peak. The lattice parameter of crystalline phase increased with W upto 40wt% which is higher than the solubility limit of W (about 30wt%) in Ni. Therefore, the alloys are considered to be Ni solid solution supersaturated with W. The amorphous Ni-W alloys were recrystallized by annealing them at temperatures over $400^{\circ}C$. This was evidenced by the appearance a strong [ 11 11 annealing texture. The supersaturated W was precipitated during the annealing at over $800^{\circ}C$. The current-density dependence of W content and crystallinity was utilized to produce alternating layers of crystalline (30wt% W) and amorphous (50wt%) phases which may exhibit unique mechanical and corrosion properties.

• Journal of Pharmaceutical Investigation
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• v.34 no.6
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• pp.443-452
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• 2004

Habit is the description of the outer appearance of a crystal. If the environment of a growing crystal affects its external shape without changing its internal structure, a different habit results. Crystal habit and the internal structure of a drug can affect bulk and physicochemical properties, which range from flowability to chemical stability. A polymorph is a solid crystalline phase of a given compound resulting from the possibility of at least two different arrangements of the molecules of that compound in the solid state. Chemical stability and solubility changes due to polymorphism can have an impact on a drug's bioavailability and its development program. During crystallization from a solution, crystals separating may consist of a pure component or be a molecular compound. Solvates are molecular complexes that have incorporated the crystallizing solvent molecule in their lattice. When the solvent incorporated in the solvate is water, it is called a hydrate. To distinguish solvates from polymorphs, which are not molecular compounds, the term pseudopolymorph is used. Identification of possible hydrate compounds is important since their aqueous solubilities can be significantly less than their anhydrous forms. Conversion of an anhydrous compound to a hydrate within the dosage form may reduce the dissolution rate and extent of drug absorption. An amorphous solid may be treated as a supercooled liquid in which the arrangement of molecules is random. Amorphous solids lack the three-dimensional long-range order found in crystalline solids. Since amorphous forms are usually of higher thermodynamic energy than corresponding crystalline forms, solubilities as well as dissolution rates are generally greater. A study on crystal form includes characterization of (l)crystal habit, (2)polymorphism, (3)pseudopolymorphism, (4)amorphous solid.

• Archives of design research
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• v.17 no.3
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• pp.51-60
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• 2004

The esthetics of 'grotesque' and its entertaining values have many things in common with the characteristics and properties of animation as a medium of expression. The ways to express grotesque images in animation have expanded its realm of expression with the development of modern image digitalization technologies. The grotesque images that were expressed by the combination of photographs and animations and objet animations have been developing its disharmony in a more realistic manner with full 3D animation technology and realistic motions of virtual characters with motion capture. The subject matter also has become more diverse with the advance of modern scientific civilization. An example is the appearance of Cyborg(cybernetic+organism) characters and the grotesque images in the modern times mainly start to appear in animations dealing with the isolation of human beings among its characteristics. Also, the changes of the expression methods of grotesque images along with the development of visual technology development in the future will transform its methodological forms by changing its expression methods to VR forms and interactive visuals. Thus it is expected that the grotesque images and characteristics will change into a visual genre which emphasizes dehumanization.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.324-327
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• 2005

An electrophoretic display using $TiO_2$ particles is the most promising candidate because it offers various advantages such as ink-on-paper appearance, good contrast ratio, wide viewing angle, image stability in the off-state and extremely low power consumption. The core technology of electrophoretic display is the dispersion controlling of $TiO_2$ nano particles in nonaqueous solution. To prepare an ink for electronic paper using electrophoretic properties of $TiO_2$ nano particles, cyclohexane with low dielectric constant and transparency, polyethylene for producing polymer coating layer which reduces apparent gravity of $TiO_2$, and $TiO_2$ powders were mixed together by planetary-mill. The zeta-potential value of $TiO_2$ particles in cyclohexane was measured about -40mV, but was measured over -110mV by dispersant attached to polyethylene-coated $TiO_2$ surface. Prepared electronic ink was filled in cross patterned micro-wall with $200{\mu}m$ in width and $40{\mu}m$ in height on ITO glass designed by photolithography. The response time of electronic paper evaluated by mobility of $TiO_2$ particle between micro-walls was measured 0.067sec, but the drift velocity from reflectance wave form during reverse from of electronic ink was measured 0.07cm/sec.

• Korean journal of food and cookery science
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• v.15 no.4
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• pp.395-400
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• 1999

This study was to investigate the effects of green tea powder addition on the quality of white bread. Initial pasting temperature on amylograph increased and peak and final viscosity decreased with the addition of green tea powder. The lightness values of bread crust decreased and lightness and redness value of bread crumb was not affected, but b values decreased with the increase of green tea powder contents. The volume was significantly reduced with addition of green tea powder up to 5.0% level, compared to that of control. The addition of green tea powder at 2.5% was not affected in most of texture parameters(hardness, springiness, cohesiveness, gumminess and chewiness). But, 10% green tea powder addition to the bread increased significantly hardness, gumminess and chewiness. As results of sensory evaluation, the bread containing 2.5% green tea powder had the highest score in appearance, color, flavor, taste, texture, and overall acceptance. Concludingly, in terms of overall properties, the addition of 2.5% green tea powder to white bread showed the best result.

• Preventive Nutrition and Food Science
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• v.1 no.1
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• pp.23-29
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• 1996

This study was conducted to investigate the changes in chemical, microbial and sensory characteristics, and antimutagenicity of buchu(leek, Allium odorum) kimchi during fermentation at 15$^{\circ}C$. Reducing sugar contents and pH of buchu kimchi were decreased during the fermentation. The reduction rate of reducing sugar of glutinous rice paste and shrimp added buvhu kimchi(GSBK) was faster than those of control buchu kimchi(CBK) and glutious rice paste added bucku kimchi(GBK). Acidity increased rapidly until 4 days,a nd optimum acidity (0.6%) of bucku kimchi was reached within 2 day. Also total bacterial and lactic acid bacterial counts greatly increased after 4 days of the fermentation. The numbers of lactic acid bacteria after 8 day- fermentation in CBK and GSBK, and 10 day-fermentation in GBK were the highest values, 4.5$\times${TEX}$10^{8}${/TEX} CFU/ml, 4.8$\times${TEX}$10^{8}${/TEX} CFU/ml and 6.1$\times${TEX}$10^{8}${/TEX} CFU/ml, respectively. In the sensory evaluation, appearance of sample was good at 0 day, taste from overall quality of buchu kimchi were asquired the highest values at 6th day. The methanol extracts from buchu kimchi(GBK) showed antimutagenicity against aflatoxin {TEX}$B_{1}${/TEX}({TEX}$AFB_{1}${/TEX})in Salmonella typhimurium TA100. The inhibition ration were 58~69% with treatment of the 5% methanol extracts, and when the adding concentration increased the effect increased.