• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.40 no.4
• /
• pp.423-430
• /
• 2014

In this study, the antioxidative effects for the extracts of purple sweet potato (Ipomoea batatas L. Lam.) were investigated. The purple sweet potato was extracted with 70% ethanol and the ethyl acetate fraction was obtained from the extracts. The yields of extract and ethyl acetate fraction were 39.2% and 3.49% per dried powder, respectively. To confirm the antioxidative effects of the extracts, free radical scavenging activities (1,1-diphenyl-2-picrylhydrazyl), total antioxidant capacity by luminol-dependent chemiluminescence assay and the protective effects against reactive oxygen species (ROS) in erythrocytes were measured. Free radical scavenging activities ($FSC_{50}$) of the 70% ethanol extract and ethyl acetate fraction were $90.16{\mu}g/mL$ and $7.69{\mu}g/mL$, respectively. The free radical scavenging activity of ethyl acetate fraction was higher than that of (+)-${\alpha}$-tocopherol ($8.98{\mu}g/mL$). Total antioxidant capacities ($OSC_{50}$) of the 70% ethanol extract and ethyl acetate fraction were $5.75{\mu}g/mL$ and $1.92{\mu}g/mL$, respectively. The capacity of ethyl acetate fraction was similar to L-ascorbic acid, known as a prominent water soluble antioxidant ($1.50{\mu}g/mL$). The cellular protective effects of the ethyl acetate fractions on the $^1O_2$-induced cellular damage of human erythrocytes were increased in a concentration dependent manner ($5{\sim}50{\mu}g/mL$). The ${\tau}_{50}$ value in $5{\mu}g/mL$ was 45.6 min which was higher than that of (+)-${\alpha}$-tocopherol in all concentrations. These results indicate that the ethyl acetate fraction of purple sweet potato (I. batatas) has the excellent antioxidative capacity and could be applicable to anti-aging cosmeceutical ingredients for skin aging inhibition.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.41 no.4
• /
• pp.391-400
• /
• 2015

In the present study, 50% ethanol extract, the ethyl acetate and aglycone fraction were prepared from mate (Ilex paraguariensis) and their antioxidative ability was evaluated. The yields of extract and fractions were 32.0, 4.48 and 0.82% per dried powder, respectively. Free radical scavenging activities were performed by 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay and total antioxidant capacity was estimated using luminol-dependent chemiluminescence assay. Free radical scavenging activities ($FSC_{50}$) of 50 % ethanol extract, ethyl acetate fraction and aglycone fraction were 8.83, 5.84 and $6.05{\mu}g/mL$, respectively. Their total antioxidant capacities ($OSC_{50}$) were similar to that of L-ascorbic acid ($1.72{\mu}g/mL$), known as a prominent water soluble antioxidant, in all extracts and 50% ethanol extract ($1.03{\mu}g/mL$) was the most effective. The cellular protective effects on the $^1O_2$-induced cellular damage of erythrocytes were evaluated and the results showed that all extracts were significantly higher than (+)-${\alpha}$-tocopherol at $10{\mu}g/mL$. Especially, the ${\tau}_{50}$ value of aglycone fraction was 5 times higher than (+)-${\alpha}$-tocopherol at $10{\mu}g/mL$ and $50{\mu}g/mL$. The inhibitory effects of the ethyl acetate and aglycone fractions on tyrosinase were similar to arbutin, known as the whitening agent in cosmetics. These results suggest that the extracts of mate have the applicability as antioxidant and anti-aging cosmeceutical ingredients.

• The Journal of Korean Medicine
• /
• v.34 no.3
• /
• pp.54-68
• /
• 2013

Objectives: This study aimed to evaluate the effects of microparticles of Socheongryong-tang (SCRT) on chronic obstructive pulmonary disease (COPD) in a mouse model. Methods: The inhalable microparticles containing SCRT were produced by spray-drying with leucine as an excipient, and evaluated with respect to the aerodynamic properties of the powder by Andersen cascade impactor (ACI). Its equivalence to SCRT extract was evaluated using lipopolysaccharide (LPS) and a cigarette-smoking (CS)-induced murine COPD model. Results: SCRT microparticles provided desirable aerodynamic properties (fine particle fraction of $49.6{\pm}5.5%$ and mass median aerodynamic diameter of $4.8{\pm}0.3{\mu}m$). SCRT microparticles did not show mortality or clinical signs over 14 days. Also there were no significant differences in body weight, organ weights or serum chemical parameters between SCRT microparticle-treated and non-treated groups. After 14 days the platelet count significantly increased compared with the non-treated group, but the values were within the normal range. Inhalation of SCRT microparticles decreased the rate of neutrophils in blood, granulocytes in peripheral blood mononuclear cells (PBMC) and bronchoalveolar lavage fluid (BALF) and level of TNF-${\alpha}$ and IL-6 in BALF on COPD mouse model induced by LPS plus CS. This effect was verified by histological findings including immunofluorescence staining of elastin, collagen, and caspase 3 protein in lung tissue. Conclusions: These data demonstrate that SCRT microparticles are equivalent to SCRT extract in pharmaceutical properties for COPD. This study suggests that SCRT microparticles would be a potential agent of inhalation therapy for the treatment of COPD.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.25 no.6
• /
• pp.245-251
• /
• 2015

We have applied mechanical alloying (MA) to produce soft magnetic composite material using a mixture of elemental $Fe_2O_3$-Mg powders. An optimal milling and heat treatment conditions to obtain soft magnetic ${\alpha}$-Fe/MgO composite with fine microstructure were investigated by X-ray diffraction, differential scanning calorimetry (DSC) and vibrating sample magnetometer (VSM) measurement. It is found that ${\alpha}$-Fe/MgO composite powders in which MgO is dispersed in ${\alpha}$-Fe matrix are obtained by MA of $Fe_2O_3$ with Mg for 30 min. The saturation magnetization of ball-milled powders increases with increasing milling time and reaches to a maximum value of 69.5 emu/g after 5 h MA. The magnetic hardening due to the reduction of the ${\alpha}$-Fe grain size by MA was also observed. Densification of the MA powders was performed in a spark plasma sintering (SPS) machine at $800{\sim}1000^{\circ}C$ under 60 MPa. X-ray diffraction result shows that the average grain size of ${\alpha}$-Fe in ${\alpha}$-Fe/MgO nanocomposite sintered at $800^{\circ}C$ is in the range of 110 nm.

• Journal of Sensor Science and Technology
• /
• v.11 no.6
• /
• pp.327-334
• /
• 2002

Fine particles of $SnO_2$ were fabricated by the sol-gel powder processing using tine(II) chloride dihydrate($SnCl_2{\cdot}2H_2O$) and ethanol($C_2H_5OH$) as raw materials. The powders were investigated about the properties and electrical sensing. Gel powders were fabricated by drying of sol at $120^{\circ}C$ after aging 72hrs and 168hrs. The amount of $SnO_2$ phase was increased below $600^{\circ}C$ due to the elimination of volatile components, and the $SnO_2$ phase was almost completed by the heat treatment at $700^{\circ}C$ for 30min. The grain sizes were about 30nm below $700^{\circ}C$, and it showed the narrow distribution of the grain sizes. The specimens to measure electrical properties were fabricated by the thick film screen printing technique on the alumina substrates. The conductance of $SnO_2$ was showed the intrinsic behaviour of semiconducting ceramics above at $450^{\circ}C$. The constant conductance was observed in the temperature range of $200{\sim}450^{\circ}C$. The sensing properties of response time, recovery, and sensitivity of CO were improved with aging time.

• 한국해양학회지
• /
• v.26 no.4
• /
• pp.313-323
• /
• 1991

Fine-grained sediments of the Han River and adjacent Kyonggi Bay have been studied using the powder x-ray diffractometer in order to study the distributional characteristics of clay minerals in the bottom and suspended sediments. The result of the XRD analyse shows that the major clay minerals in the lower Han River are composed of illite (57.1%), kaolinite (22.9%), and chlorite (19.6%) and that those of the Han River Estuary are composed of illite (67.2%), chlorite (16.5%), kaolinite 915.5%), and smectite (1.3%). The variation of mineral content shows distinct distributional characteristics depending on sedimentary environments. The illite content increases gradually approaching the Kyonggi Bay and kaolinite content decreases toward the sea within the range between 11% and 23%. The trend of chlorite is similar to that of kaolinite, the amount of which ranges between 14% and 19%. Smectite content is lower than 3%. Analysis of illite using peak-intensity ratio (001/002) indicates that two types of illites occur in the study area. Dioctahedral-type illite occurs as an indicator of the marine sediments. The illites distributed between the Kyonggi Bay and the Han River are mixtures of dioctahedral- and trioctahedral-types. This study indicates that the distribution of illite, kaolimite, and chlorite has been influenced mainly by the supply from the Han River and redistributed by estuarine circulation, such as tidal circulation and seasonal variation of river discharge. However, smectite is apparently supplied from other sources such as Yellow Sea or China. This study suggests that estuarine mixing system and seasonal variations of river discharge are the major factors controlling the distribution pattern of clay minerals in the study area.

• Journal of Advanced Marine Engineering and Technology
• /
• v.36 no.2
• /
• pp.276-285
• /
• 2012

The objective of this research is to develop the coating technique by a porous self-fluxing alloy for improving the mechanical properties of run-out table roller surface with the hot rolling. To enhance the durability of run-out table roller with the hot rolling, the high hardness of roller surface should be maintained at high temperatures, and the improvement of wear resistance, corrosion resistance, heat resistance, burn resistance and adhesion resistance should be maintained. In order to be able to transport reliably a hot rolled steel sheet, also, the appropriate friction coefficient on the roller surface should be maintained and the slip between roller and steel should not occur. In this study, the wear resistance of roller increases after the self-fluxing alloy is changed to a cermet by adding the tungsten carbide(WC), and the coefficient of friction increases and the ability of grip is improved because the porosities are made by coating with fine iron powder on the roller surface. As a result, it is found that the ability of grip between the steel and the roller coated by a porous self-fluxing alloy contained to 5 ~ 10 wt% of Fe in the coating layer is improved compared to the roller coated by Ni-Cr. This is because the porosities are made after Fe contained in the roller is partially alloyed by heating with a furnace in the fusing process and the rest is eliminated by oxidation and dissolution.

• Journal of Conservation Science
• /
• v.32 no.3
• /
• pp.417-423
• /
• 2016

The effect of the glue solution were investigated in the grinding and elutriation process for manufacturing of White clay pigment. In grinding process, glue solution decreased the production of a too fine powder and enhanced the degree of sorting of ground pigments. The grinding performance and limit are generally influenced by the frictional force. Therefore, the friction force was measured in accordance with the grinding conditions. As a result of measuring a friction force, when using glue solution it showed the lowest friction. Finally, the application of glue solution in grinding process is believed to enhance the degree of sorting of ground pigments by reducing frictional force. In elutriation process, the application of glue solution enabled the screening of larger particles in the same conditions by reducing the sedimentation velocity. This result is due to increase in the viscosity of the glue solution according to glue concentration. As a result, the application of glue solution in elutriation process is though to enlarges the range of the selectable particle size and to enable the segmentation of the particles.

• Journal of Conservation Science
• /
• v.32 no.3
• /
• pp.313-320
• /
• 2016

The aim of this study was to obtain information on the ancient material of cast bronze through an investigation of the microstructure and impurity characteristics of the casting. Three Koryo bronze coins were analyzed using an optical microscope, scanning electron microscope, and electron dispersive X-ray analyses were used to determine the composition of the specimens. The three coins had 4 phases: ${\alpha}phase$, ${\delta}phase$, Pb, and impurities ($Cu_2S$). $Cu_2S$ was found to exist near Pb or in ${\delta}phase$. $Cu_2S$ is the inter mediate product of copper ore refining. Therefore, the copper ore was not completely refined. To find out the characteristic of $Cu_2S$, we melt 1)Koryo bronze coin and 2)$Cu_2S$ and Pb powder at 1273 K. The reaction between $Cu_2S$ and Pb at 1273 K yielded fine Cu and black gas, which was identified to be PbS and is presented below: $Cu_2S+Pb{\rightarrow}PbS{\uparrow}+2Cu$.

• Journal of the Korea Concrete Institute
• /
• v.21 no.1
• /
• pp.55-64
• /
• 2009

This study is aimed to derive the optimum mix proportion of the combined self compacting concrete according to cement types (blast-furnace slag cement and belite cement) and to propose the basic data to field construction work after evaluating the quality properties. Specially, lime stone powder (LSP) as binder and viscosity agent are used in the combined self compacting concrete because slurry wall of an underground LNG storage tank should be kept stability of quality during concrete working. Replacement ratio of LSP is determined by confined water ratio test and main design factors including fine aggregate ratio ($S_r$), coarse aggregate ratio ($G_v$) and water-cement ratio (W/C) are selected. Also, quality properties including setting time, bleeding content, shortening depth and hydration heat on the optimum mix proportion of the combined self compacting concrete according to cement type are compared and analyzed. As test results, the optimum mix proportion of the combined self compacting concrete according to cement type is as followings. 1) Slag cement type-replacement ratio of LSP 13.5%, $S_r$ 47% and W/C 41%. 2) Belite cement type-replacement ratio of LSP 42.7%, Sr 43% and W/C 51%. But optimum coarse aggregate ratio is 53% regardless of cement types. Also, as test results regarding setting time, bleeding content, shortening depth and hydration heat of the combined self compacting concrete by cement type, belite cement type is most stable in the quality properties and is to apply the actual construction work.