• Food Science and Preservation
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• v.16 no.5
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• pp.669-674
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• 2009

We prepared puffed instant Nuroong-gi samples using a microwave and investigated the physicochemical characteristics of the products. The quality of Nuroong-gi prepared using a microwave was compared with that of noodles prepared in a steam cooker and pressure cooker in terms of moisture content, color, water binding capacity ratio, viscosity, sedimented volume of insoluble solids, turbidity, and sensory evaluation. The moisture content of Nuroong-gi prepared in a microwave was similar to that of steam cooker and pressure cooker samples. The color (lightness) of steam cooker-prepared noodles was greater than that of noodles cooked using other modes. The water binding capacity ratio fell with increasing microwave cooking time. The viscosity of noodles prepared using a microwave was higher than that of pressure cooker samples and lower than that of steam cooker noodles. The sedimented volume of insoluble solids and turbidity increased with a rise in cooking temperature. Nuroong-gi prepared in a microwave scored higher in sensory evaluation tests than did steam cooker or pressure cooker samples. These results indicate that Nuroong-gi preparation using a microwave is very efficient.

• Korean Journal of Food Science and Technology
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• v.36 no.2
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• pp.276-282
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• 2004

Barley flakes were developed by extrusion cooking using broken kernels, by-products of the barley pearling process. Broken kernels from both non-waxy and waxy barley broken kernels were sufficiently gelatinized at the barrel temperature of over $100^{\circ}C$ and the moisture content of broken kernels of over 35%. Cutting and flaking roll separating properties of pellets prepared from non-waxy barley broken kernels were better than those of waxy barley broken kernels. Characteristics of pellets prepared by extrusion cooking in different mixing ratios of non-waxy and waxy barley broken kernels were investigated. As the mixing ratio of waxy barley broken kernels increased, RVA peak viscosity, apparent viscosity, and yield stress of prepared pellets decreased, while flow behavior index increased. As the mixing ratio of waxy barley broken kernels increased, compressive strength and bulk density of deep-fat fried flakes drastically decreased, and the size of air cells on cross-section increased, and thickness of cell-constituting bodies decreased. Sensory evaluation results showed that acceptability for texture and taste of flakes inclosed as the mixing ratio of waxy barley broken kernels increased, and optimum mixing level of waxy barley broken kernels appeared to be 30-40%.

• Membrane Journal
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• v.21 no.1
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• pp.55-61
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• 2011

$BaCo_{0.7}Fe_{0.22}Nb_{0.08}O_{3-{\delta}}$ oxide was synthesized by solid state reaction method. Dense ceramic membrane was prepared using as-prepared powder by pressing and sintering at $1,200^{\circ}C$. XRD result of membrane showed single perovskite structure. Leakage and oxygen permeation test were conducted on the membrane sealed by glass ring as a sealing material. The oxygen permeation flux increased with increasing temperature and pressure difference and maximum oxygen permeation flux was $2.3mL/min{\cdot}cm^2$ at $950^{\circ}C$ with $Po_2$ = 0.63 atm of oxygen partial pressure. The oxygen permeation in the condition of air with $CO_2$ (300 ppm) as feed stream decreased as much as only maximum 2.9% in comparison with air feed stream. It indicated $BaCo_{0.7}Fe_{0.22}Nb_{0.08}O_{3-{\delta}}$ membrane is more stable than another membrane for carbon dioxide.

• Korean Journal of Materials Research
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• v.11 no.3
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• pp.178-184
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• 2001

Transparent and highly oriented KLN thin films have been grown by an rf- magnetron sputtering deposition method. A homogeneous and stable KLN target was prepared by calcine and sintering process. For KLN target, stoichiometry and composition excess with K of 30% and 60%, and Li of 15% and 30% respectively, was prepared. The targets were sintered at low temperature to prevent vaporization of K and Li. KLN thin films were fabricated by rf-magnetron sputtering method using those targets. In this experiment, using the target of composition excessed with K of 60% and Li of 30%, single phase KLN thin film was produced. KLN thin film has excellent crystallinity and highly c-axis oriented on Corning 1737 substrate. Transmittance of thin film in visible range was 90%, absorption edge is 333 nm and refractive index at 632.8 nm was 1.93.

• Korean Chemical Engineering Research
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• v.56 no.1
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• pp.119-124
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• 2018

The production of methyl N-phenyl carbamate by an oxidative carbonylation method of aniline and methanol is of great interest as an environmentally friendly process that can replace the monomer production process of a polymer produce using conventional phosgene. In this study, heterogeneous catalysts were prepared by using Y-zeolite, $SiO_2$, $Al_2O_3$ as support, and oxidative carbonylation continuous operation from aniline and methanol was attempted using the prepared heterogeneous catalyst. Batch reactor was used to determine the support, and various reaction conditions such as reaction temperature, reaction pressure, and effect of promoter were established using palladium catalyst. A reaction kinetics study was conducted under optimum reaction conditions. The basic data for carbamate process development were obtained by performing continuous operation for a long time under established reaction condition.

• Journal of the Korean Ceramic Society
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• v.39 no.9
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• pp.846-850
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• 2002

A PMN-PT-BT/Ag composite was prepared by surface modification with MgO sol with hoping to suppress silver's migration during sintering. The mixture of PbO, $N_2O_5,\;TiO_2\;with\;Mg(NO_3)_2$ instead of MgO was ball milled, the solvent was removed and then the dried powders were calcined at 950$^{\circ}C$/1h. The calcined powder were treated with 3.0 mol% $Ag_2O$ and 1.0 wt% MgO sol and calcined at 550$^{\circ}C$/1h. The dielectrics sintered at 1000$^{\circ}C$/4h under a flowing oxygen showed the density of 7.84g/$cm^3$, the room temperature dielectric constant of 18400, the dielectric loss of 2.4%, the specific resistivity of $0.24{\times}10^{12}{\Omega}{\cdot}cm$. It also showed the bending strength of $120.7{\pm}11.26$ MPa and the fracture toughness of $0.87{\pm}0.002\;MPam^{1/2}$ which were comparable to commercial PZT. The microstructure sonsisted of grains of ∼4${\mu}m$. SEM and SIMS analysis showed that Ag grew as ∼1${\mu}m$ and excess MgO as ∼0.5${\mu}m$.

• Resources Recycling
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• v.14 no.2
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• pp.19-27
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• 2005

The recycling possibility of aluminum waste dross(AWD) as a ceramic raw material of porous light-weight material was examined. A aluminum waste dross was washed 4-7 consecutive times and roasted at 900$^{\circ}% for 1hour as pre-treatments. The properties of the pre-treatment of aluminum waste dross was investigated. It was conformed by XRD result that the spinel crystalline was grown in AWD, after roasting. After the roasted AWD was ground in aqueous state, the sodium hexaphosphate(SHP) as a dispersant which is used for stabilizing the concentrated slurry was added to the AWD slurry. The porous material was prepared by slurry foaming method with surfactant at room temperature. The foamed slurry volumes were 2 and 3 times of the original slurry volume. The properties of porous material with extended volume of 3 times was following: the porosity was about 84%, bulk density was 0.59 g/cm$^3$, the range of pore was from 50 ${\mu}m$ to 500 ${\mu}m$ and mean pore size was about 200 ${\mu}m$. AWD porous material was sintered at 1150$^{\circ}C-1250$^{\circ}C. It was colcluded that AWD was sintered well at 1200$^{\circ}C from material surface observation by SEM.

• Membrane Journal
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• v.22 no.1
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• pp.8-15
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• 2012

Tubular $Ba_{0.5}Sr_{0.5}Co_{0.8}Fe_{0.2}O_{3-{\delta}}$ membranes with $La_{0.6}Sr_{0.4}Ti_{0.3}Fe_{0.7}O_{3-{\delta}}$ porous coating layer were prepared by extrusion and dip coating technique. XRD and SEM result showed the tubular membrane possessed the perovskite structure and porouscoating layer (thickness= about $2{\mu}m$) in surface. The oxygen permeation test was measured at condition of ambient air (feed side) and vacuum (permeate side) in the temperature range from 750 to $950^{\circ}C$. The oxygen permeation flux of $Ba_{0.5}Sr_{0.5}Co_{0.8}Fe_{0.2}O_{3-{\delta}}$ tubular membrane with $La_{0.6}Sr_{0.4}Ti_{0.3}Fe_{0.7}O_{3-{\delta}}$ porous coating layer reached maximum $3.2mL/min{\cdot}cm^2$ at $950^{\circ}C$ and was higher than non-coated $Ba_{0.5}Sr_{0.5}Co_{0.8}Fe_{0.2}O_{3-{\delta}}$ tubular membrane. Long-term stability test result indicated that the oxygen permeation flux was quite stable during the 11 day.

• Biomolecules & Therapeutics
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• v.6 no.2
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• pp.213-218
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• 1998

A novel in situ-gelling and mucoadhesive acetaminophen liquid suppository was developed to improve the patient compliance of conventional solid suppository. In this study, acetaminophen liquid suppository, Likipe $n_{R}$, ［aminophen/Poloxamer 407/Poloxamer 188/so4ium alginate (5/15/19/0.6%)] with relation temperature at 30-36 "C and suitable gel strength and bioadhesive force, dissolution pattern similar to conventional solid type suppository, Suspe $n_{R}$, was developed. Furthermore, the bioequivalence of two acetaminophen products was evaluated in 16 normal male volunteers (age 22-27 yr, body weight 56-72 kg) following sidle rectal administration. Test product was Likipe $n_{R}$ suppository (Dong-Wha Pharm. Corp., Korea)and reference product was Suspe $n_{R}$204-212 suppository (Hanmi Pharm. Corp., Korea). Both products contain 125 mg of acetaminophen. Four Suppositories of the test and the reference product were administered to the volunteers, respectively, by randomized two period cross-over study (2$\times$2 Latin square method). The determination of acetaminophen was accomplished using HPLC. Average drug concentrations at each sampling time and pharmacokinetic parameters calculated were not significantly different between two products (p>0.05); the area under the curve to last sampling time (24 hr) (AU $Co_{-2}$4h/) (30.14$\pm$8.64 vs 27.98$\pm$ 6.53 $\mu$g .h/ml), maximum plasma concentration ( $C_{max}$) (3.29$\pm$0.87 vs 3.60$\pm$0.66 $\mu$g/ml) and time to maximum plasma concentration ( $T_{max}$) (2.91 $\pm$0.55 vs 2.69$\pm$0.60 h). The differences of mean AUCo $_{24h}$, C-a. and T-between the two products (7.18%, 9.58% and 7.53%, respectively) were less than 20%. The power (1-7) and treatment difference ($\Delta$) for AU $Co_{24h}$, $C_{max}$ and $T_{max}$ were more than 0.8 and less than 0.2, respectively at $\alpha$=0.1. The confidence limits for AU $Co_{24h}$, $C_{max}$ and $T_{max}$ (-0.81 ~13.55%, -1.56~ 17.60 and -3.81 ~18.87%, respectively) were less than $\pm$ 20% at $\alpha$=0.1. These results suggest that the bioavailability of Likipe $n_{R}$ suppository is not significantly different from that of Suspe $n_{R}$ suppsitory. Therefore, two products are bio-equivalent based on the current results.results.lts.sults.results.lts.

• Applied Chemistry for Engineering
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• v.16 no.6
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• pp.772-777
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• 2005

Porous hydrated lime and limestone filters were prepared by foaming and gelcasting method, and their physical properties were evaluated. Through these analyses, it has been found that with the increased porosity and pore size of the filters, majority of pores in the filters were inter-connected by windows. Also, $SO_2$ removal efficiency for the filters was investigated. As the porosity and the reaction temperature increased, $SO_2$ removal efficiency also increased. Especially, unlike the variation of entrance concentration, the entrance flow rate had great influence on the removal efficiency. In case of the filters with an equal porosity, the hydrated lime filter had superior removal efficiency compared to the limestone filter. From these results, it was shown that the high conversion ratio to CaO from the hydrated lime filter was a result of facilitated formation of $CaSO_4$ by $SO_2$.