• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 2005.10a
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• pp.131-135
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• 2005

In general, the application of HP contributes to improvement of functionalities of meat protein. In the current study, HP allowed the lower thermal processing of restructured meat product. Low thermal processing allowed fresh-like meat color which is one of problems in hot-set restructuring, while they showed slight discolorization induced by HP. In addition, HP processing combined with thermal processing could be achieved the palatable binding strength in restructured meat product. The addition of non-meat protein had an effect in binding strength. However, they showed no effect on water binding properties at 200 MPa, especially in milk proteins such as casein and whey protein. This is probably due to protein aggregation or to increase in surface hydrophobicity under HP. This result indicates that the application of HP on meat restructuring is more significant than the addition of binders. Therefore, the application of HP has apotential benefit in restructured meat product, and further investigations are needed.

• Proceedings of the Botanical Society of Korea Conference
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• 1999.04a
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• pp.18-18
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• 1999

We characterized a cDNA clone for a low molecular weight heat-shock protein (LMW HSP) from tobacco named TLHS-l. Nucleotide sequence determination of TLHS-1 identified an open reading frame for 159 amino acids. To the upstream of the open reading frame, a sequence of 124 nucleotides was determined. To the 3' downstream of the open reading frame, 212 nucleotides were identified which carried poly(A)-tail. Comparison of the open reading frame and hydropathy plot of TLHS-1 with the previously reported class I LMW HSPs showed high identity which classified TLHS-1 as a class I LMW HSP cDNA clone. We proposed that there are six consensus regions in class I LMW HSPs. RNA blot hybridization for TLHS-1 showed a typical expression pattern of heat-shock-inducible gene from three common tobacco cultivars. The open reading frame of TLHS-1 was overexpressed in Escherichia coli. TLHS-1 protein confers thermal protection of other proteins in vitro and in vivo. Thermal induced aggregation of citrate synthase was reduced by purified TLHS-1 protein, and thermal death rate at $50^{\circ}C$ was reduced in E. coli expressing TLHS-l. From these data, we can expect that TLHS-1 acts as a molecular chaperone.perone.

• Bulletin of the Korean Chemical Society
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• v.33 no.12
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• pp.3987-3992
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• 2012

Silver nanopowders were prepared from silver 2-ethylhexylcarbamate (Ag-EHCB) complexes by simple thermal reduction at $85^{\circ}C$ without any reducing agent in organic solvent. 2-Ethylhexylammonium 2-ethylhexylcarbamate (EHAEHC) was investigated in terms of their abilities to stabilize the silver nanoparticles (Ag-NPs) and its subsequent effects on the preventing aggregation between Ag-NPs. Conditions (concentration of stabilizer and reaction time) used to reduce Ag-EHCB complex were systematically varied to determine their effects on the sizes of Ag-NPs. The formation of the stabilized Ag-NPs were easily monitored by UV-vis spectroscopy and characterized by TGA, TEM, SEM and XRD. When EHAEHC was used as a stabilizer, Ag-NPs of 10-30 nm in diameter were easily obtained in high yield. Silver patterns were obtained from a silver nano-paste by heat treatment at $200^{\circ}C$ in air and were found to have resistivity values of $2.9{\times}10^{-8}\;{\Omega}{\cdot}m$.

• Journal of Korean Association for Spatial Structures
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• v.21 no.2
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• pp.99-110
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• 2021

This study presents the estimation of crack depth by analyzing temperatures extracted from thermal images and environmental parameters such as air temperature, air humidity, illumination. The statistics of all acquired features and the correlation coefficient among thermal images and environmental parameters are presented. The concrete crack depths were predicted by four different machine learning models: Multi-Layer Perceptron (MLP), Random Forest (RF), Gradient Boosting (GB), and AdaBoost (AB). The machine learning algorithms are validated by the coefficient of determination, accuracy, and Mean Absolute Percentage Error (MAPE). The AB model had a great performance among the four models due to the non-linearity of features and weak learner aggregation with weights on misclassified data. The maximum depth 11 of the base estimator in the AB model is efficient with high performance with 97.6% of accuracy and 0.07% of MAPE. Feature importances, permutation importance, and partial dependence are analyzed in the AB model. The results show that the marginal effect of air humidity, crack depth, and crack temperature in order is higher than that of the others.

• Polymer(Korea)
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• v.38 no.4
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• pp.484-490
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• 2014

Reduced graphene oxide (RGO) was fabricated using gelatin as a reductant, and it could be stably dispersed in gelatin solution without aggregation. A series of RGO/gelatin composite films with various RGO contents were prepared by a solution-casting method. The structure and thermal properties of the RGO/gelatin composite films were characterized by UV-vis spectroscopy, Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), atomic force microscopy (AFM), scanning electron microscopy (SEM), differential scanning calorimeter (DSC) and thermal gravimetric analysis (TGA). The addition of RGO enhances the degree of crosslinking of gelatin films and decreases the swelling ability of the gelatin films in water, indicating that RGO/gelatin composite films have a better wet stability than gelatin films. The glass transition temperature ($T_g$) of gelatin films is also increased with the incorporation of RGO. The presence of RGO slightly increases the degradation temperature of gelatin films due to the very low content of RGO in the composite films. Since gelatin is a natural and nontoxic biomacromolecule, the RGO/gelatin composite films are expected to have potential applications in the biomedical field.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.538-541
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• 2008

The carbon laden suspensions in water with no surfactants have poor stability caused by the hydrophobic layer of particles. In this study, the water-based carbon nano colloide(CNC) was successfully produced using electro-chemical one-step method without agent. The properties of CNC were characterized by using various techniques such as particle size analyzer, TEM, FT-IR, turbidity meter, viscometer, and transient hot-wire method. The average size of the suspended in the CNC was 15 nm in diameter. The thermal conductivity of CNC compared with water was increased up to 14% with 4.2wt% concentration. The CNC was stable over 600hr. The enhanced colloidal stability of CNC may be caused by the chemical structures, such as, hydroxide and carboxyl groups formed in outer atomic layer of carbon, which (i) made the carbon nanofparticles hydrophilic and (ii) prevented the aggregation among nanoparticles.

• Korean journal of food and cookery science
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• v.33 no.3
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• pp.307-315
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• 2017

Purpose: To develop nano-sized starch particles for application as dietary fiber sources in liquid food system, the morphology and thermal properties of acid hydrolyzed rice starches with different amylose contents were evaluated. Methods: Rice starches purified from three Korean cultivars, including Goami, Hopyeong, and Hwaseonchal, were hydrolyzed with 2.2 N HCl solution in a $35^{\circ}C$ shaking water bath (100 rpm) for 7, 10 and 15 days. Results: Acid hydrolysis rates of rice starches increased with increasing hydrolysis duration, and rates for Goami, Hopyeong, and Hwaseonchal were 28.74-38.50%, 38.96-49.53%, and 40.24-48.88%, respectively. The granular size of acid hydrolyzed starches decreased to 122.4-479.9 nm, whereas granular aggregation increased with increasing hydrolysis duration. In particular, waxy rice starch of Hwaseonchal was composed of many tiny granules without aggregates. Gelatinization temperature and temperature range increased with increasing hydrolysis duration. All starches showed A type crystallinity using an x-ray diffractometer, regardless of acid hydrolysis. Conclusion: It is suggested that nanoparticles could be prepared by acid hydrolysis of rice starches, and waxy rice starch is the most preferred source for application.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.465-465
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• 2008

Conjugated polymers have attracted much scientific and technological research interest during the past few decades because of their potential use such as polymer light-emitting diodes (PLEDs).1,2 Particularly, lots of phenylene-based polymers such as polyfluorene and its derivatives have been synthesized because of their high photoluminescence quantum efficiencies and thermal stabilities. However, troublesome long wavelength emission in polymer film of polyfluorenes on heating during device formation or operation has been the crucial problem for practical applications. The source of the long wavelength emission was initially believed to be solely due to excimer emission as a result of polymer aggregation. It has also recently been correlated with emissions from ketonic defects in the fluorene units. Many efforts have been made to reduce the tendency to red-shifted emission. Here, we report for the first time the design and synthesis of novel 9,9-spiro bifluornene-based polymers containing heteroatoms such as N, S in its molecular skeleton. Especially, the 9,9-spiro bifluornene-based polymers containing N atom showed stable blue electroluminescence, which did not show spectral change upon thermal annealing.

• Proceedings of the Korean Fiber Society Conference
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• 1997.10a
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• pp.32-35
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• 1997

Aggregation states ans electro-optic properties of a binary mixture by mixing a side chain type liquid crystalline polymer(LCP) and a low molecular weight liquid crystal(LMLC) have been studied. Side chain liquid crystalline polysiloxanes were synthesized from allyl bromide, p-hydroxy benzoic acid, p-cyanophenol, p-methoxyphenol and polysiloxanes. Low molecular weight liquid crystals were synthesized from allyl bromide, p-hydroxy benzoic acid and 4-cyano 4'-hydroxy biphenyl. And then, their properties were compared with blended liquid crystals. The thermal properties of the blended liquid crystals were evaluated using differential scanning calorimetry. The phase behavior of blended sample with temperature were also observed polarized microscope with hot stage. Thus, it seemed to us that a study of LC polysiloxanes with LMLC would be useful, especially in view of the fact that, systematic investigations have been carried out on the effects of changes in LCP/LMLC binary system on the properties of this relatively new type of liquid crystal.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.28 no.1
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• pp.214-224
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• 2002

High concentrated $TiO_2$ nano colloids were synthesized by sol-gel method. Reactions were performed in $TiCl_4$/HCl/$H_2O$ aqueous solution and the conditions of particles such as shape, size and aggregation, etc. were controlled by polymerization and adsorption of acrylamide in surface of $TiO_2$ nano particles. And also, aminopropyltriethoxysilane was added instead of acrylamide and compared each other. The prepared colloids were well dispersed and showed the strong absorption peaks at 350nm-370nm which is blue shifted to 20-30nm, compared to macro particles. The obtained techniques from $TiO_2$ nato colloids synthesis were utilized in coating on boron nitride powders which are nonpolar and isoelectronic materials of carbon. Their surface morphology, structure, thermal stability and U. V absorption chracteristics were examined by SEM(Scanning Electron Microscopy), XRD(X-ray diffraction), TG/DTA(Thermogravimetric and Differential Thermal Analysis), UV-VIS(Ultraviolet-Visible Spectroscopy).