• Korean Journal of Food Science and Technology
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• v.20 no.3
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• pp.344-349
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• 1988

Proteolysis of 7S and 11S soy protein-rich fraction(PRF) with commercial proteases(alcalase and pronase) apperently increased protein solubility at pH 5, heat coagulation and calcium tolerence, while decreasing emulsifying capacity and foam stability regardless of the kind of protein and protease used. However, the proteolysis decreased the protein solubility of 7S PRF at pH 6 and 11S PRF at pH 4. The proteolysis of 11S PRF increased oil absorption and foam expansion, while slight decrease or almost no change was noted on 7S PRF. Heat stabilities of the emulsion and kinetic viscosities changed very little by the proteolysis.

• Food Science of Animal Resources
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• v.30 no.3
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• pp.373-384
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• 2010

The present paper describes the effect of cooking temperature on objective meat qualities and volatile components in beef longissimus lumborum. Twenty samples of lumbar vertebrae longissimus muscle from Australian Black Angus (grain-fed and chiller aged for 29 d) were screened. Samples were cooked at 50, 70 or $90^{\circ}C$ in a pre-heated water bath for 1 h and uncooked raw samples were used as control. The results revealed that elevating the heating temperature from 50 to $90^{\circ}C$ led to a significant (p<0.05) increase in WB-shear force, total energy required for WB-shear force, cooking loss, pH and soluble collagen content, whereas a significant (p<0.05) linear decrease in protein solubility was observed. The results also revealed that the WB-shear force at $70^{\circ}C$ was significantly (p<0.05) lower than that observed at $50^{\circ}C$ and $90^{\circ}C$. However, the effect of temperature on cooking loss and protein solubility was notably (p<0.05) higher at $70^{\circ}C$. The detectable volatile components were mostly produced from fat oxidation, and temperature effects on the generation of volatile components were significantly (p<0.05) greater for aldehydes (hexanal, benzaldehyde, nonanal and octanal) than for ketones and hydrocarbons (hexane, benzene, decan, toluene and 3-methylnonane).

• Korean Journal of Food Science and Technology
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• v.19 no.1
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• pp.61-65
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• 1987

The milk protein portion contains sialic acid which may be used as an index for k-casein. In comparison with non fat dry milk (NFDM) and calcium caseinate, the solubility of NFDM protein isolates at the various pH was inferior. Another consideration for the low solubility relates to the possibility that k-casein may have been extracted or possibly modified by the action of alcohol. The k-casein is the principal stabilizing fraction for casein micelle and any changes which result in its destruction or removal would be expected to have potent results. During solvent treatment, 16.5% of sialic acid was extracted in the first extraction solvent, whereas the second treatment caused only a 4.0% loss, based on sialic acid analysis. A study was conducted on the effect of concentration of methanol on loss of sialic acid. The loss of sialic acid decreased as the concentration of methanol increased to above 62% in both the first and second extracted solvent. It appears that loss of sialic acid is attributed to the water fraction rather than the methanol fraction. The effect of addition of the dried extracted solids on solubility was investigated. Protein solubility of NFDM protein isolates was sharply increased by 10% addition of the extracted solids and, thereafter, decreased. Efforts to restore solubility by feeding-back the extracted material supported the concept that removal of surface k-casein may have been a possible factor.

• Journal of Microbiology and Biotechnology
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• v.25 no.2
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• pp.247-254
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• 2015

In this presentation, I describe the expression and purification of the recombinant liver X receptor β-ligand binding domain proteins in E. coli using a commercially available double cistronic vector, pACYCDuet-1, to express the receptor heterodimer in a single cell as the soluble form. I describe here the expression and characterization of a biologically active heterodimer composed of the liver X receptor β-ligand binding domain and retinoid X receptor α-ligand binding domain. Although many of these proteins were previously seen to be produced in E. coli as insoluble aggregates or "inclusion bodies", I show here that as a form of heterodimer they can be made in soluble forms that are biologically active. This suggests that co-expression of the liver X receptor β-ligand binding domain with its binding partner improves the solubility of the complex and probably assists in their correct folding, thereby functioning as a type of molecular chaperone.

• Journal of Applied Biological Chemistry
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• v.42 no.4
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• pp.180-185
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• 1999

Protein concentrate was produced and succinylated from rice bran to assess and improve its functional properties for the purpose of expanding the uses of rice bran proteins. The most effective solvent for the extraction of rice bran proteins was 20% aqueous ethanol at pH 9. The protein content of rice bran protein concentrate produced was 70.0% and the total protein yield was 64.3%. The extent of succinylation of free amino groups in the modified products was 72.8%. Though the modified protein products showed good functional properties including solubility, emulsion properties, and oil absorption capacity, it did not form gel. Succinylation improved solubility and emulsion and gelling properties. These improvements in functionality will enhance the value of rice bran proteins, thus enabling them to be more competitive with other food proteins.

• Bulletin of the Korean Chemical Society
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• v.10 no.3
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• pp.270-272
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• 1989

The polymeric species formed on the hydrolysis of Th(IV) from solubility experiments of $ThO_2$ in 0.1M $NaClO_4$ and $Th(OH)_4\;in\;0.5M\;NaClO_4$ were removed by ultrafiltration using 1 nm ultrafilters. The resultant equilibrium concentrations of mono-hydroxy Th(IV) species in solutions between pH 1.5 to 13 were measured by the NAA method. From these data solubility product of thorium dioxide and the stability constants of mono-hydroxy Th(Ⅳ) were determined. The values obtained were log $K_{sp}\;-\;50.76\;{\pm}\;0.08, log\;{\beta}_{1,1}\;12.42\;{\pm}\;0.02,\;log\;{\beta}_{1,2}\;22.46\;{\pm}\;0.15, log\;{\beta}_{1,3}\;34.36\;{\pm}\;0.07,\;log\;{\beta}_{1,4}\;42.58\;{\pm}\;0.08$, which are in good agreement with the values given in the literature. In addition, several dimeric species, $Th_2(OH)_2\;^{6+},\;Th_2(OH)_3\;^{5+} and\;Th_2(OH)_4\;^{4+}$ have been identified.

• Proceedings of the Korean Society For Composite Materials Conference
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• 1999.11a
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• pp.32-35
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• 1999

Poly(arylene ether phosphin oxide) (PEPO), Udel$^{\circledR}$ P-1700, Ultem$^{\circledR}$ 1000. poly(hydroxy ether) (PHE), carboxy modified poly(hydroxy ether)(C-PHE) and poly(hydroxy ether ethanol amine) (PHEA) were utilized for a coating of carbon fibers. Interfacial shear strength(IFSS) of polymers to carbon fibers was also evaluated in order to understand the adhesion mechanism. IFSS was measured via micro-droplet tests, and failure surfaces were analyzed by SEM. Diffusion between polymer and vinyl ester resin was investigated as a function of styrene content; 33. 40 or 50wt.% and the solubility parameters of polymers were calculated. The results were correlated to the interfacial shear strength. The highly enhanced interfacial shear strength (IFSS) was obtained with PEPO coating, and marginally improved IFSS with PHE, Udel$^{\circledR}$ and C-PHE coatings, but no improvement with PHEA and Ultem$^{\circledR}$ coatings.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.1 no.1
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• pp.100-106
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• 1991

Ba.Fe - hydroxide precipitates were obtained by the variation of pH levelsm, which process was based on the calculated solubility from the solubility product(Ksp). Single phase $BaFe_12O_19$ was synthesized above $790^{\circ}C$. The 98% of theoretical density was obtained in the specimens formed from the filter cake drying and the hand pressing at temperatures $95^{\circ}C$ and $1,100^{\circ}C$ for 2hrs, respectively. The feezing of colloidal coprecipitate suspension formed powders up to several tens of micron size, which led to reduce the filtration time and the consumption of distilled water.

• Korean Journal of Materials Research
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• v.27 no.8
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• pp.445-450
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• 2017

YSZ (Yttria-stabilized zirconia) is a ceramic material that is used for electronic and structural materials due to its excellent mechanical properties and specific electrical characteristics according to the Yttrium addition. Hydrothermal synthesis has several advantages such as fine particle size, uniform crystalline phase, fast reaction time, low process temperature and good dispersion condition. In order to synthesize YSZ nanoparticles with high crystallinity, hydrothermal synthesis was performed at various concentrations of NaOH. The hydrothermal process was held at a low temperature ($100^{\circ}C$), with a short process time (2,4,8 hours); the acidity or alkalinity of solution was controlled in a range of pH 2~12 by addition of NaOH. The optimum condition was found to be pH 12, at which high solubility levels of Y(OH) and Zr(OH) were reported. The synthesized nano powder showed high crystallinity and homogenous composition, and uniform particle size of about 10 nm.

• Resources Recycling
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• v.20 no.6
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• pp.56-62
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• 2011

Zirconium is used in nuclear reactors as a structural material due to its excellent corrosion resistance and to low neutron crosssection. Variation in the distribution and solubility of Zr(IV) with solution pH was obtained. Distribution of Zr(IV) containing species in HCl and $HNO_3$ solution was analyzed by considering the complex formation of Zr(IV) species with the anion of the inorganic acid. Bromley interaction parameter between $ZrO^{2+}$ and nitrate ion was estimated by using the reported data on the solvent extraction of Zr(IV) by Cyanex272 from $HNO_3$ solution. This Bromley parameter can be utilized in calculating extraction isotherm of Zr(IV) and in predicting the separation factor between Zr(IV) and Hf(IV).