• Korean Journal of Food Science and Technology
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• v.32 no.6
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• pp.1285-1290
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• 2000

The objective of this study was to evaluate the characteristics on the thermal denaturation of free drip released from pork loin during chilled storage using DSC (differential scanning calorimetry) with pH, concentration of NaCl and phosphate. The increasing of pH stabilized the heat resistance of the proteins in drip. A $T_1$ greatly increased of $T_{max}$ by $6.33^{\circ}C$ incline from pH 5.5 to 6.5. And increasing the concentration of NaCl destabilized the heat resistance of drip. $T_1$ showed the greatest reduction of $T_{max}\;(9.41^{\circ}C)$ in the presence of 5% NaCl. The presence of STPP (Sodium Tripolyphosphate) enchanced the thermal stability of pork drip by $5.84^{\circ}C$ in the presence of 0.5% STPP. As temperature increased from 40 to $100^{\circ}C$, lightness $(L^*)$ increased from 41.1 to 69.5, while redness $(a^*)$ decreased from 26.70 to 5.40. Particularly, both values of $L^*-$ and $a^*-$ greatly changed by 78% from 40 to $60^{\circ}C$.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.5
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• pp.3304-3311
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• 2014

In the saponification to manufacture plant fatty acid hard soap, the drying process is required for its water evaporation and hardness. This study mixed it with essential oil(E.O) with high volatility instead of adding synthetic flavor. And it comparatively observed the duration of flavor changing to the additive ($TiO_2$) and the drying period of the major flavor component (Linalool, Linalyl acetate) in the essential oil (Lavender E.O) contained in the soap during the soap manufacture by using GC-MS. Advanced researches have mostly dealt with the utility of plant hard soap, and those related with the volatility of flavor have been hardly conducted. Regarding the volatility of linalool contained in the soap, the soap mixed with $TiO_2$ showed a higher reduction ratio up to the 12th week; however, at the point of the 20th week, it reduced to a similar level. Although Linalyl acetate did indicate a slight difference according to the mixture of $TiO_2$, the volatility was shown similar up to the point of the 20th week. During the 20 weeks of drying, the residual rate of linalool was found to be higher than that of Linalyl acetate regardless of the mixture of $TiO_2$. It has been found that the flavor component of lavender essential oil with the duration of two or so days at the room temperature remains for 20 weeks (or 5 months) when it is manufactured through the mixture of plant fatty acid hard soap.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.5
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• pp.607-611
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• 1999

Carrageenan are sulfated polymers containing galactose and anhydrogalctose units, and is used for its gelling, thickening, stabilizing, emulsifying, and suspending properties. However, carrageenan is limited to use beyond $0.03\%$ as food additives because of its high degree of gelling and viscosity with low solubility. The use of ultrasound significantly reduced the viscosity of $\lambda$-carrageenan solutions. The optimal parameters of ultrasound for reduction of carrageenan molecular weight were temperature, $10^{\circ}C$ ultrasound intensity, 114.7 $W/cm^2$ ; carrageenan concentration, $2\%$; treatment time, 10 min. The molecular weights of control, ultrasound peak 1, and peak 2 were approximately 250,000, 184,000, and 67,000 daltons, respectively. The lower molecular weight of $\lambda$-carrageenan showed the higher solubility, the lower alcohol precipitation ratio and the lower emulsifying capacity. Browning degree of both control and lower molecular $\lambda$-carrageenans was not significantly different.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.32 no.4
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• pp.495-500
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• 1999

The carrageenans are linear, sulfated Polysaccharides extracted from various species of the Rhodophyta (marine red algae). The carrageenan backbone is based on a repeating disaccharide sequence of $\beta$-D-galactopyranose residues linked glycosidically through position 1 and 3, and $\alpha$-D-galactopyranose residues linked glycosidically through position 1 and 4. Carrageenans are typical food polysaccharides in that food applications overwhelmingly dominate their end uses. Other applications, hewer, including cosmetics, pharmaceuticals, industrial suspensions and paints are also of importance But because of its high degree of gelling and viscosity with low solubility, carrageenan is limited to use beyond $0.03\%$ as food additives. Response Surface Methodology was applied for optimizing the processing parameters of ultrasound treatment in order to produce low-molecular-weight carrageenan. The use of ultrasound significantly reduced viscosity of $\lambda$-carrageenan solutions. Optimal parameters for ultrasound reduction of carrageenan molecular weight were: temperature, $10^{\circ}C$; ultrasound intensity, 121.64 $W/cm^2$ ; tarrageenan concentration, $2\%$; treatment time, 40 min. As the gel permeation chromatogram of dextran standards (M.W.= 500,000 ; 260,000 ; 167,000 ; 71,400 ; 42,000) and ultrsound treated carrageenan, the molecular weight of ultrasound treated carrageenan were approximately 200,000 (peak 1) and 60,000 (peak 2), respectively.

• Resources Recycling
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• v.15 no.4 s.72
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• pp.36-43
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• 2006

There was some difficulty dewatering properties due to small porosity diameter of cake, when pigment sludge contained fine particle was formed by cake under the dewatering. It was difficult to dewater the sludge with fine particles with the conventional mechanical dewatering method. This study was to improve the dewatering rate as discharging the water from porosity of cake easily, supplying the low heat to the cake layer. Thermal dewatering equipment of piston type to keep up constant temperature on the cake was set up and relative experiment was conducted for sludge of 200 g with fine pigment particle. As test results. filtration of 176.8 g, cake weight of 19.4 g, cake thickness of 4.2 mm was measured, and it was analyzed that the water content of cake was 47 wt% and dewatering velocity, which moaned the residual d교 sloid amount per dewatering area, was $2.1DS\;m^{2}{\cdot}cycle$. This results showed that filtration increased, cake weight and thickness decreased and dewatering velocity increased against mechanical dewatering method. And water content of cake decreased about 30%, so the result which dewatering rate improved was drew generally. The reason is that the inner vapor pressure working at the cake porosity increased as applying the low heat to the cake layer, which lead to discharge the water from porosity easily. Therefore, this study was estimated by the useful technology for sludge reduction.

• Resources Recycling
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• v.13 no.5
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• pp.28-36
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• 2004

The extraction of platinum group metals such as Pt, Pd and Rh from spent automobile catalyst has been investigated by leaching in HCl solutions using $HNO_3$ or NaOCl as a oxidant. The effect of type and amount of oxidant, reaction time and pulp density on the extraction of platinum group metals was examined. Platinum group metals were recovered by the cementation method using aluminum as a reducing agent. The extraction ratio was higher when NaOCl was used as a oxidant. The optimum leaching conditions were obtained to be: HCl 8 M, the amount of NaOCl 1.4 mole, leaching temperature $90^{\circ}C$, leaching time 180 minutes, pulp density 400g/L. Under the optimum conditions, the extraction of Pt, Pd and Rh were 96.1%, 93.6% and 77.3%, respectively. With the addition of 2.0g of aluminum which corresponds to 28 equivalent the reduction were 98% for Pt. 98.8% for Pd and 65.3% for Rh, respectively.

• Resources Recycling
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• v.25 no.6
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• pp.73-81
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• 2016

Geopolymers produced from aluminosilicate materials such as metakaolin and coal ash react with alkali activators and show higher fire resistance than portland cement, due to amorphous inorganic polymer. The percentage of thermal shrinkage of geopolymers ranges from less than 0.5 % to about 3 % until $600^{\circ}C$, and reaches about 5 ~ 7 % before melting. In this study, geopolymers paste having Si/Al = 1.5 and being mixed with carbon nanofibers, silicon carbide, pyrex glass, and vermiculite, and ISO sand were studied in order to understand the compressive strength and the effects of thermal shrinkage of geopolymers. The compressive strength of geopolymers mixed by carbon nanofibers, silicon carbide, pyrex glass, or vermiculite was similar in the range from 35 to 40 MPa. The average compressive strength of a geopolymers mixed with 30 wt.% of ISO sand was lowest of 28 MPa. Thermal shrinkage of geopolymers mixed with ISO sand decreased to about 25 % of paste. This is because the aggregate particles expanded on firing and to compensate the shrinkage of paste. The densification of the geopolymer matrix and the increase of porosity by sintering at $900^{\circ}C$ were observed regardless of fillers.

• Journal of the Korean Chemical Society
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• v.36 no.4
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• pp.552-557
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• 1992

Chloramphenicol was studied by differential pulse polarography (DDP). A reduction peak which is dependent on pH of the solution appeared in the voltage range between zero and -1.50 volt vs. Ag/AgCl (sat. KCl) reference electrode. A plot of peak potentials (Ep) measured at room temperature (20$^{\circ}C$) vs. pH of the chloramphenicol solutions showed linear relationship changing slope (Ep/pH) at pH 8.9. The slope was -59.7 mV/pH in pH 2.7∼8.9 and -24.3 mV/pH in pH 8.9∼11.2, respectively. A log plot of peak currents (ip) vs. concentrations showed a linearity at the concentrations between 4.8 ${\times}$ 10$^{-7}$ M and 6.2 ${\times}$ 10$^{-5}$ M (0.16 ppm∼20 ppm) chloramphenicol in pH 8.0 ammonium buffer. Between the DPP method and the reference method measuring absorbance at 278 nm, the correlation coefficient was 0.996, which means an excellent linearity. The DPP method was able to detect degradation products of chloramphenicol in mild alkaline solution (pH = 8.0) more distinctly than the spectrophotometric method.

• Polymer(Korea)
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• v.34 no.4
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• pp.313-320
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• 2010

New cinnamate group-containing copolymers for a self-curable, humidity-sensitive polyelectrolyte and polymeric anchoring agents were prepared by copolymerization of [2-[(methacryloyloxy) ethyl]dimethyl]propyl ammonium bromide(MEPAB), methyl methacrylate(MMA), 3-(trimethoxysilyl) propyl methacrylate(TMSPM) and 2-(cinnamoyloxy)ethyl methacrylate(CEMA). Photocrosslinkable copolymer composed of MEPAB/MMA/TMSPM/CEMA＝70/20/0/10 were used for humidity-sensitive membrane, and those of 50/0/20/30 and 0/0/50/50 were used for polymeric anchoring agents. 3- (Triethoxysilyl)propyl cinnamate(TESPC) was also used as a surface-pretreating agent for the comparison of capability of attachment of polyelectrolyte to the electrode surface with polymeric photocurable silanecoupling agents. Pretreatment of the electrode substrate with anchoring agents was performed to form a cinnamate thin film on the electrode through covalent bonds. When the sensors were irradiated with UV light, the anchoring of a polyelectrolyte into the substrate was carried out via the [2$\pi$+2$\pi$] cycloaddition. The resulting sensors using polymeric anchoring agents and TESPC showed water durability with increase of resistance by 60~85%, which is corresponding to the reduction of 2.25~3.15%RH, after soaking in water for 24 h. They showed good hysteresis (-0.2%RH), response time (90 sec) and long-term stability at high temperature and humidity.

• Korean Journal of Plant Resources
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• v.13 no.3
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• pp.162-170
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• 2000

This study quantified the effects of urban greenspace on microclimate amelioration and atmospheric $CO_2$ reduction for several residential districts selected in Korea and Japan. The study also explored fire obstruction by urban trees to develop systematic planting guidelines. Transpiration by a Zelkova serrata tree (diameter at breast height: 15 cm) in a day of August equaled cooling effect of about 3 air conditioners running for 12 hours. Average air temperature for the growing season was 0.5$^{\circ}C$ and 1.2$^{\circ}C$ cooler, respectively, in districts with 12% and 22% cover of woody plants than in a district with no vegetation. Annual $CO_2$ uptake and $O_2$ production by woody plants were 3 times greater in a district which was 2 times higher in their cover. Woody plants played, in a district with their 22% cover, an important role through offsetting total $CO_2$ emission from the district by about 3% annually, and through producing 10% of annual $O_2$ requirement by all residents within the district. Appropriate planning strategies of residential greenspace, including species selection, planting layout, greenspace enlargement, and maintenance were suggested to improve microclimate amelioration, air purification, and fire obstruction.