• Journal of Ocean Engineering and Technology
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• v.25 no.6
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• pp.97-104
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• 2011

Modified C95600 bronze contains Fe component of 0.7 weight percentage besides Cu-7Al-2.5Si composition. The shape of centrifugal cast is a circular pipe with thick wall. Specimens machined from the centrifugal cast were quenched in oil after isothermal holding at a given heat treatment temperature in the range of $700{\sim}900^{\circ}C$. Mechanical properties and structural morphology are depended on the quenching heat treatment temperature regardless of isothermal holding time. Tensile strength or Brinell hardness is increased with increasing heat treatment temperature. The microstructure caused by quenching contains mixing phases of ${\alpha}+{\beta}'+FeSi+{\kappa}$ which martensite of ${\beta}'$ phase has been transformed from ${\beta}$ phase. Effect of isothermal holding temperature on mechanical properties in case of quenching heat treatment attributes to the change of volume fraction of ${\beta}'$ on the structural morphology. Mechanical characteristics of specimen, initially quenched from $850^{\circ}C$, and then tempered at $500^{\circ}C$, does not show an obvious softening indication, because disappearance of ${\beta}'$ during tempering process can be compensated by precipitation of brittle phase ${\gamma}$.

• Resources Recycling
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• v.5 no.1
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• pp.3-8
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• 1996

CZS(2Ca0 , SiO\ulcorner) phase of cement clinkcr was obtaincd by melting mixcd four indnstrial wasles of limestone sludge, waste Foundry sand, coal lly ash fiorn power plants and chernicas glasses. The effect ot mixing ratio of four rvastc mater~als ou the composnlg phascs in melled slag was investigated. Thc mixed wastes were meltcd to slag by heat under a constant basicity at 1370C. The shg consisted of p -CIS and C,AS(2CaO - A I P , . SiO,). The ratio of two phases was varied with mixing ~atioo f the waste materials. In order Lo increasc the amount ot j -C2S phase, the coal fly ash content should be reduced, while amount of the chemical glass be increased. The coal fly ash contcnt was the most imporlant factor in controlling phases of thc melted-slag.

• The Korean Journal of Food And Nutrition
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• v.31 no.6
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• pp.940-948
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• 2018

The aim of this study was to investigate the immune activity of Ailantias altissima as an active ingredient on the immune enhancement by mixing ethanol extract with lactic acid bacteria (LAB). The activity of $NF-{\kappa}B/AP1$ transcription factor increased by $NF-{\kappa}B$ activity when mixed with LAB samples rather than with the extract alone. Nitric oxide (NO) production was similar in ethanol extract alone group and LPS treatment group. Mixing Ailantias altissima extract and lactic acid bacteria led to low NO production. The cytokine productivity of $TNF-{\alpha}$ significantly increased in Ailantias altissima extract when treated with LPS, and increased even more when mixed with lactic acid bacteria. The $IL-1{\beta}$ cytokine production was high when the Ailantias altissima extract were treated alone, but no $IL-1{\beta}$ cytokine was produced in the mixtures with isolates. The combination of the ethanol extract of the Ailantias altissima and the lactic acid bacteria was found to be effective in the immune function. Consequently, the ingredient to combine Ailantias altissima extract and lactic acid bacteria can be effectively used for development of the health functional food on the prevention and treatment of hypoimmunities.

• KSBB Journal
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• v.10 no.2
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• pp.149-158
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• 1995

The capacity of inclusion complex formation between ${\alpha}$-, ${\beta}$-, ${\gamma}$-cyclodextrins(CDs) and various compounds, such as pH indicators, biloslalns, glycoside, amino acid, and fatty acids, was compared. Fatty acid was identified as the most suitable ligand for fractionation of CDs in terms of capacity and selectivity. The effects of complex formation conditions, such as, mixing ratio of CD and fatty acid, pH, ionic strength, and temperature, on the capacity of fatty acrid-CD complex was also investigated. The carbon number of fatty acids was identified as the most significant factor determining the capacity and selectivity of inclusion complex formation of CDs. Capric acid(C10) and palmitic acid(C16) showed high specificity for ${\alpha}$- and ${\beta}$-CDs, respectively. Under the optimal conditions, the molar ratio of complex formed was found to be 1.0:2.6 for ${\alpha}$-CD/capric acid and 1.0:1.9 for ${\beta}$-CD/palmitic acid. X-ray diffraction and infrared spectrum of the formed inclusion complex were analyzed. The changes of enthalpy($\Delta$H) of the inclusion complex formation reaction was evaluated by differential scanning calorimetry, showed that the reaction was endothermic.

• Journal of the Korean Ceramic Society
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• v.41 no.3
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• pp.202-209
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• 2004

Hydroxyapatite(HA)/TiO$_2$ composite powders were prepared by mixing of spherical TiO$_2$ (10-15 nm, 500 nm) and needle-shaped HA (50-70 nm, 120-250 nm) powders which had been synthesized through precipitation, sol-gel and hydrothermal methods. From the three types of starting composite powders (HA/TiO$_2$ wt% of 75/25, 50/50, and 25/75), dense $\beta$-TCP/TiO$_2$ composites were prepared by hot-pressing at 800-100$0^{\circ}C$ for 30 min under the pressure of 30 ㎫ in Af atmosphere. The $\beta$-TCP/TiO$_2$ composites showed different microstructures and sintering densities depending on their powder morphology, composition and sintering temperature. With increasing the sintering temperature and the content of TiO$_2$, sintered density was increased and microstructure became more homogeneous.

• KSBB Journal
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• v.17 no.4
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• pp.357-364
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• 2002

For the effecient extraction methods of essential oil, pretreatment of leaves, ratios of water and leaves, extraction time, and collection season from the Chamaecyparis obtusa and Chamaecyparis pisifera leaves were studied. The chemical composition of essential oil was analyzed by GC-MS. The yield of essential oil from ground leaves was higher than that of chopped leaves. The yield of essential oil was not affected much by mixing ratios of water and leaves. The yield of essential oil reached maximum after 5 hours. The content of essential oil of C. obtusa leaves collected during winter was 4.5%, whereas the content of essential oil of C. pisifera collected during fall was 5.3%. The composition of essential oils extracted form C. obrusa and C. pisifera was different. The major constituents in the essential oil of C. obtusa were monoterpene as limonene, terpinene-4-ol, ${\gamma}$-selinene, and a-cedrene, and those of C. pisifera was monoterpens as ${\alpha}$-pinene, myrcene, limonene, bornyl acetate, ${\beta}$- caryophyllene, longifolene, and ${\beta}$-cedrene.

• Korean Journal of Materials Research
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• v.3 no.5
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• pp.505-513
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• 1993

To make the electrophotographic photoreceptor that srnsirizes for panchromatic matcrial, the dying element of sunfasr yellow which has an absorption ivavclength at near 400nm, and $\alpha,\beta$-copper phthalocyaninc dying elements with 700nm absorption wavelength were adsorbed and then dispersed onto the zine oxide(Zn0). In ordcr to characterize rhe change In sensitivity the various binders and different mole ratio of ZnO to binder were employed in here. It was found rhat the optimum sensitivity was obtained with 5.5 ratio. I;rom the measurements of electrostatic and spectral sensitivity, it was found that the maximum photographic properties were obtained for mixing the sunfast yellow and $\beta$-copper phthalocyaninr. In this case the electrophotographic sensiri\ity was found to he $E{1:2}$= 1440 lux . sec. And also the spectral sensitivity shows that it had a good properties for panchromatic matcrial.

• Resources Recycling
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• v.6 no.1
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• pp.23-28
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• 1997

Iron and slag were prepared by melting mixed industrial wastes in an induction furnace. The wastes were steel can, limestone sludge, waste foundry sand, coal fly ash, and glasses. The effects of their mixing ratio on the charactenstics of the meltcd slag were investigated. The wastes were melted to slag under the constant basicity of 1.2. It was found that the major phases of the slag were P-C,S and C,AS and then ratio was determined by the mixing ratio af waste materials. The recovery of iron was about 93-95%. The feasibility of using the slag as the aggregate was confirmed by thc elution and campression tests.

• Journal of the Korean Society of Food Science and Nutrition
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• v.44 no.11
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• pp.1708-1714
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• 2015

Fermented red ginseng concentrate is known as a healthy food source, whereas it has off-flavor such as bitterness and sour flavor based on fermentation. ${\beta}$- and ${\gamma}$-cyclodextrin (CD) were used to encapsulate the off-flavor of fermented red ginseng concentrate by using response surface methodology design on ${\beta}$- and ${\gamma}-CD$ combination. The reducing effects were analyzed by sensory evaluation for bitter and sour tastes, ginsenoside Rb1, and total acidity. The optimized mixing ratio of ${\beta}$- and ${\gamma}-CD$ for reducing bitterness was the least expected value of 2.07 at ${\beta}-CD$ 3.74% versus the soluble solid content of fermented red ginseng concentrate and the ${\gamma}-CD$ 20.63% mixture. The encapsulation effects of ginsenoside Rb1 were the most expected value of 96.75% at ${\beta}-CD$ 3.47% and ${\gamma}-CD$ 19.89% mixture. The encapsulation effects of sour taste were the least expected value of 5.63 at ${\beta}-CD$ 9.34% and ${\gamma}-CD$ 9.96% mixture. The encapsulation effects of lactic acid were the most expected value of 67.73% at ${\beta}-CD$ 16.0% and ${\gamma}-CD$ 13.18% mixture. Based on encapsulation and each optimized combination, the most effective entrapping ${\beta}$-and ${\gamma}-CD$ combination ratio was ${\beta}-CD$ 10% and ${\gamma}-CD$ 13%.

• Applied Chemistry for Engineering
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• v.10 no.7
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• pp.1086-1091
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• 1999

$K^+-{\beta}/{\beta}"-Al_2O_3$ in the ternary system $K_2O-MgO-Al_2O_3$ was directly synthesized by solid state reaction. The phase formation and phase relation were carefully investigated in relation to starting composition, calcining temperature and time, and dispersion medium. The optimal synthetic condition was also examined for the formation of ${\beta}"-Al_2O_3$ phase with a maximum fraction. As a composition range, the mole ratio of $K_2O$ to $Al_2O_3$ was changed from 1:5 to 1:6.2 and the amount of MgO used as a stabilizer was varied from 4.2 wt % to 6.3 wt %. The calcining temperature was selected between $1000^{\circ}C$ and $1500^{\circ}C$. At $1000^{\circ}C$, the ${\beta}/{\beta}"-Al_2O_3$ phases began to form resulted from the combining of ${\alpha}-Al_2O_3$ and $KAlO_2$ and increased with temperature rising. All of ${\alpha}-Al_2O_3$ phase disappeared to be homogenized to the ${\beta}/{\beta}"-Al_2O_3$ phase at $1200^{\circ}C$. Near the temperature at $1300^{\circ}C$, the fraction of ${\beta}"-Al_2O_3$ phase showed a maximum value with the composition of $K_{1.67}Mg_{0.67}Al_{10.33}O_{17}$. At temperatures above $1300^{\circ}C$, the fraction of ${\beta}"-Al_2O_3$ phase decreased gradually owing to $K_2O$ loss caused by a high potassium vapor pressure, and the appropriate calcining time was about 5 hours. Acetone was more effective than distilled water as a dispersion medium for milling and mixing.