• Structural Engineering and Mechanics
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• v.77 no.1
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• pp.103-114
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• 2021

Ultra high strength concrete (UHSC) originally proposed by Richards and Cheyrezy (1995) composed of cement, silica fume, quartz sand, quartz powder, steel fibers, superplasticizer etc. Later, other ingredients such as fly ash, GGBS, metakaoline, copper slag, fine aggregate of different sizes have been added to original UHSC. In the present investigation, the combined effect of coarse aggregate (6mm - 10mm) and steel fibers (0.50%, 1.0% and 1.5%) has been studied on UHSC mixes to evaluate mechanical and fracture properties. Compressive strength, split tensile strength and modulus of elasticity were determined for the three UHSC mixes. Size dependent fracture energy was evaluated by using RILEM work of fracture and size independent fracture energy was evaluated by using (i) RILEM work of fracture with tail correction to load - deflection plot (ii) boundary effect method. The constitutive relationship between the residual stress carrying capacity (σ) and the corresponding crack opening (w) has been constructed in an inverse manner based on the concept of a non-linear hinge from the load-crack mouth opening plots of notched three-point bend beams. It was found that (i) the size independent fracture energy obtained by using above two approaches yielded similar value and (ii) tensile stress increases with the increase of % of fibers. These two fracture properties will be very much useful for the analysis of cracked concrete structural components.

• Progress in Superconductivity
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• v.3 no.2
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• pp.198-212
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• 2002

The effects of reacted precursors on phase evolution, microstructure, $J_{c}$ and junctional characteristic of the inter-granular contacts were investigated in Ag-sheathed T1-1223 tapes prepared using three kinds of reacted precursors, and compared to those in the tape prepared using an unreacted precursor The precursors were prepared by heat-treating a mixture of Sr-Ba-Ca-Cu-O, $Tl_2$$O_3$, PbO and $Bi_2$$O_3$ powders at $805^{\circ}C$ (precursor I ), $840^{\circ}C$ (precursor II ) and $905^{\circ}C$(precursor III) for 20 min. Tl-1223 phase content, grain size and J\ulcorner in the tapes appeared to increase in an order of precursors I, II and III Compared to tapes prepared using an unreacted precursor, the tapes prewar ed using precursors II and III revealed reduced pore and impurity densities and an enhanced texture. Also characteristic of inter -granular contacts and fraction of strong-links were improved. The improved properties are attributed to enhanced densification resulting from using the reacted precursors.s.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2020.10a
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• pp.221-221
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• 2020

Curcumin, a hydrophobic polyphenol derived from turmeric, has been used a food additive and as a herbal medicine for the treatment of various diseases. In the present study, we found the functional role of a nanosphere loaded with curcumin (CN) in the promotion of the motility of human umbilical cord blood derived mesenchymal stem cells (hUCB-MSCs) during the wound closure. We found that the efficacy of hUCB-MSCs migration induced by CN was 1000-fold higher than that of curcumin powder. CN significantly increased the motility of hUCB-MSCs by activating c-Src, which is responsible for the phosphorylation of protein kinase C (PKC) and extracellular signal-regulated kinase (ERK). CN induced the expression levels of α-actinin-1, profilin-1 and filamentous-actin, as regulated by the phosphorylation of nuclear factor-kappa B during its promotion of cell migration. In a mouse skin excisional wound model, we found that transplantation of UCB-MSCs pre-treated with CN enhances wound closure, granulation, and re-epithelialization at mouse skin wound sites. These results indicate that CN is a functional agent that promotes the mobilization of UCB-MSCs for cutaneous wound repair.

• Food Science and Preservation
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• v.31 no.2
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• pp.245-255
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• 2024

The proximate composition, quality characteristics, antioxidant activity, and sensory evaluation scores of yakgwa added with mealworm powder (MP) were examined. MP contained 5.83 wt% moisture, 55.70 wt% crude protein, 35.96 wt% crude fat, 3.70 wt% crude ash, and 2.43 wt% carbohydrate and feature total polyphenol and flavonoid contents of 406.52 mg GAE/100 g and 21.18 mg NE/100 g, respectively. The DPPH and ABTS^•+ radical scavenging activities and the reducing power of MP were determined as 90.25%, 44.06%, and 1.74, respectively. Except for moisture and carbohydrate content, the proximate composition of mealworm yakgwa (MY) increased with the amount of MP increased. The pH of the dough increased with the addition of MP, whereas the expansion degree tended to decrease. Sugar content was highest at MP contents of 0 wt% and 12 wt% (FM4 group), and hardness was lowest in the FM4 group. With the increasing MP content, the L, b values and antioxidant activity increased, whereas a value decreased. The sensory evaluation scores for the overall preference, appearance, color, and taste were lowest in the FM4 group. These results suggested that MP contents of 6-9 wt% were optimal for mealworm-based yakgwa.

• Economic and Environmental Geology
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• v.51 no.4
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• pp.345-358
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• 2018

In this study, we have performed electron probe micro analyzer (EPMA), X-ray differaction (XRD), inductively coupled plasma spectroscopy (ICP), Fourier transform Raman spectroscopy (FT-Raman), far-infrared (FIR), nuclear magnetic resonance (NMR), and pH-DO Analyses for characterizing medicinal mineralogy aspect of the black tourmaline (Shantung, china), black and pink tourmaline (Minas Geraris, Brazil), black touemaline (Daeyu mine, Korea). In addition, heating effects of the tourmaline sauna as well as the effects of tourmaline powder-added soap on skin troubles have been investigated. It has been revealed that chemical composition of the tourmaline is either high in Fe-, Al-, B-rich types. Ratio of the K-Ca, Na-K, and Fe-B reflects the component change property of solid solution. $CaO/CaO+Na_2O$ and MgO/FeO+MgO ratio show high positive correlation. When tourmaline reacts with distilled water, extended reaction time DO values approximately decrease and it stabilizes at DO = 10. Otherwise, pH values increase until 6 hours and it stabilizes at pH = 8 after 24 hours. Distilled water changes to alkaline when it reacts with tourmaline powder and particles. Tourmaline showed lower absorption spectrum strength and transmittance at short wave, where absorption spectrum wavelength and strength were determined by the content of the composition elements and characteristics of crystallography. Increase of the Fe content has been confirmed to be the cause for the reduction of irradiation. For the chemical composition and spectral property of the tourmaline particle samples, it has been found that Si and Fe contents show positive correlation with Far-Infrared irradiation, while Al and Mg contents show negative correlation. For tourmaline powder, it has been confirmed that $^{17}O-NMR$ FWHM (full width at half maximum) decreases when reacts with distilled water. Tourmaline sauna (approximately $100^{\circ}C$) was found to increase $0.5-1.5^{\circ}C$ of body temperature, average of 12 heartbeat, and 10mg Hg of blood pressure. Tourmaline soap had very good aesthetic effect to skin and was confirmed to have above the average improvements to skin troubles (e.g., allergy or atopy).

• Proceedings of the Ginseng society Conference
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• 1984.09a
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• pp.13-19
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• 1984

In the previous symposium, authors reported about anti-atherogenic action of Panax ginseng, saying that red-ginseng powder increased serum HDL-cholesterol, decreased total cholesterol, TG, NEFA, in addition, decreased platelet adhesiveness. Later, Toyama group including me. reported that ginsenosides esp. $Rb_2$ enhanced HDL and decreased LDL. Also Matsuyama group and Kinki Univ. group reported that ginsenosides $Rg_1,\;Rb_2,$ etc. inhibited platelet aggregation. This paper will be divided into two parts: Experimental and clinical Experimental study; Using a highcholesterol-cholic acid-fed rats, effects of red ginseng extract and several ginsenosides on serum apoprotein-lipoproteins in relation to prostaglandins. Rats received $2\%$ cholesterol 1-1$\%$ cholic acid diet, ginseng extract or ginsenosides 2.5mg/100g/day for 9 days. Red ginseng extract, ginsenosides $Rb_2,\;Rc,\;Rb_1,\;and\;Rg_1,\;esp.\;Rb_2,$ increased HDL, apo-AI, Aii and $PGI_2,$ while they decreased LDL, apo-B and $TXA_2$. Clinical study: Effect of red ginseng powder on hyperlipidemia was observed. Long term administration of red ginseng powder manufactured by Office of Monopoly, Republic of Korea and offered by Japan-Korea Korean Ginseng Co., Kobe, at the dose of 2.7 g/day, was performed in patients with hyperlipidemia up to 4 years. The significant increase in serum HDL-cholesterol and also the significant decrease in total cholesterol, atherogenic index, TG, NEFA and lipoperoxide was observed with 3-48 month administration of red ginseng. Conclusions: Red ginseng and ginsenosides improved hyperlipidemia in rats and in man, with the improvement of blood apoproteins, lipoproteins and prostaglandins in experimental hyperlipidemic animals.

• Food Science and Preservation
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• v.14 no.5
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• pp.497-503
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• 2007

In order to develop a new rice bran danmooji, changes in physicochemical characteristics and texture of danmooji treated with rice bran, Stevia rebaudiana Bertoni leaf powder, succinic acid, or yeast extract were investigated during salting for 90 days. The PH of rice bran danmooji decreased from PH6.41 initially to pH 4.09 (control group), pH 4.10 (S. rebaudiana treatment S1), pH 3.84 (S. rebaudiana + succinic acid treatment S2), and pH 3.90 (S. rebaudiana+succinic acid+yeast extract treatment S3) after 90 days of salting. At this time, the salinities of rice bran danmooji of the S1, S52, and S3 groups were 2.32%, 1.94% and 2.15% respectively. The hardness of all groups decreased rapidly in the first 30 days of salting, and thereafter showed no changes. After 90 days of salting, the hardness of all groups was $1,186-1,368\;g/cm^2$ with no significant differences between groups. Redness, the a value, of the S2 and S3 groups treated with succinic acid, was lower than that of S3, whereas yellowness, the b value, of S3 treated with succinic acid and yeast extract was the highest of the three groups. Sensory evaluation of rice bran danmooji after 90 days of salting resulted in S3 attaining the highest scores for flavor, taste, texture, and overall acceptability. These results indicate nut high-quality rice bran danmooji may be prepared by addition of S. rebaudiana leaf powder, succinic acid and yeast extract to rice bran.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.5
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• pp.759-765
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• 2013

In this study, we investigated the quality characteristics of Sikhye, a traditional Korean drink, made with various amounts (0.5, 1, 2, and 3%) of powder from the roots of Doraji (RPD), for different storage periods (1, 3, 5, 7, 10, 13, or 15 days). The pH and Hunter's L value of Sikhye decreased with higher amounts of added RPD, while saccharinity as well as "a" and b values increased. During storage, pH and Hunter's L value of Sikhye tended to decrease while "a" and b values increased. The saccharinity of Sikhye with 0.5% and 1% RPD reached its maximum values on the tenth storage day and continuously decreased during the storage period. In contrast, the saccharinity of Sikhye with 2% and 3% RPD increased during the storage period, and had its maximum saccharinity on the fifteenth storage day. During the storage of Sikhye the total microbial cell count, typically $3.19{\sim}0.35{\times}10^2$ CFU/mL on the third storage day, was undetected in Sikhye with 3% RPD. The total microbial cell count of Sikhye without RPD increased to $1.91{\times}10^9$ CFU/mL by the fifteenth storage day, while Sikhye with 0.5, 1, 2, and 3% RPD added contained $8.43{\times}10^8$, $9.77{\times}10^7$, $2.10{\times}10^7$, and $7.21{\times}10^6$ CFU/mL, respectively. Thus, the total cell count was lower with higher additions of RPD. In sensory tests, the Sikhye control, or with 0.5% and 1% RPD added, didn't show significant differences in the texture of rice granules, plumpness of rice granules, floating of rice granules, taste, flavor, and sweetness values. The overall preference was highest (5.38) for Sikhye with 0.5% RPD, followed by the control, 1% RPD, 2% RPD and 3% RPD. In conclusion, according to preference tests, we recommended the addition of 0.5% or 1% RPD in Sikhye.

• Food Science of Animal Resources
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• v.29 no.3
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• pp.382-390
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• 2009

This study was carried out to determine the effects of tomato powder (TP) as nitrite (NT) on pork patties. The following treatments were made: 0.01% NT (Tl), 0.01% NT and 1.0% TP (T2), 0.5% TP (T3), 1.0% TP (T4), and 0.01% NT and 1.0% TP (T5) were in basal formula (C). The following observations were made: T5 displayed lower gumminess and adhesiveness values than those of C and T1 (p<0.05) on Day 1 of storage; the hardness and surface hardness of T3 and T4 were relatively lower and the surface hardness and gumminess of T3 were relatively higher than the others (p<0.05) on Day 21 of storage; Y4 had significantly lower TBARS values than the others during storage; VBN values of the tested groups were significantly lower than the control samples on Day 7 and 21 of storage; T3 and T4 samples displayed lower pH values (p<0.05) than the control samples on Day 21 of storage; T3, T4 and T5 revealed lower CIE $L^*$ and W than those of C and T1 during storage; T2 had the highest CIE $a^*$ (p<0.05); T4 had significantly higher CIE $b^*$ and chroma values than those of others; T3 and T4 had significantly lower total plate counts than the others; T1 had significantly lower yeast and mold and Staphylococcus sp. counts than the other groups'; and T1 and T2 displayed significantly higher color acceptability than the others.

• Korean Journal of Mineralogy and Petrology
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• v.34 no.3
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• pp.169-176
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• 2021

This study aimed to fundamentally understand structural changes of zeolite under pressure and in the presence of different pressure-transmitting media (PTM) for application studies such as immobilization of heavy metal cation or CO₂ storage using pressure. High-pressure X-ray powder diffraction study was conducted on the zeolite-W (K_6.4Al_6.5Si_25.8O₆₄× 15.3H₂O, K-MER) to understand linear compressibility and the bulk moduli in different PTM conditions. Zeolite-w is a synthetic material having the same framework as natural zeolite merlinoite ((K, Ca_0.5, Ba_0.5, Na)₁₀ Al₁₀Si₂₂O₆₄× 22H₂O). The space group of the sample was identified as I4/mmm belonging to the tetragonal crystal system. Water, carbon dioxide, and silicone-oil were used as pressure-transmitting media. The mixture of sample and each PTM was mounted in a diamond anvil cell (DAC) and then pressurized up to 3 GPa with an increment of ca. 0.5 GPa. Pressure-induced changes of powder diffraction patterns were measured using a synchrotron X-ray light source. Lattice constants, and bulk moduli were calculated using the Le-Bail method and the Birch-Murnaghan equation. In all PTM conditions, linear compressibility of c-axis (𝛽^c) was 0.006(1) GPa^-1 or 0.007(1) GPa^-1. On the other hand, the linear compressibility of a(b)-axis (𝛽^a) was 0.013(1) GPa^-1 in silicone-oil run, which is twice more compressible than the a(b)-axis in water and carbon dioxide runs, 𝛽^a = 0.006(1) GPa^-1. The bulk moduli were measured as 50(3) GPa, 52(3) GPa, and 29(2) GPa in water, carbon dioxide, and silicone-oil run, respectively. The orthorhombicities of ac-plane in the water, and carbon dioxide runs were comparatively constant, near 0.350~0.353, whereas the value decreased abruptly in the silicone-oil run following formula, y = -0.005(1)x + 0.351(1) by non-penetrating pressure fluid condition.