• Title/Summary/Keyword: Hydration activity

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Evaluation of Durability Performance in Concrete Incorporating Low Fineness of GGBFS (3000 Grade) (저분말도 고로슬래그 미분말(3000급)을 혼입한 콘크리트의 내구성능평가)

  • Lee, Seung-Heun;Cho, Sung-Jun;Kwon, Seung-Jun
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.23 no.4
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    • pp.96-102
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    • 2019
  • When GGBFS(Ground Granulated Blast Furnace Slag) with high blaine is incorporated in concrete, compressive strength in the initial period is improved, but several engineering problems arise such as heat of hydration and quality control. In this paper, compressive strength and durability performance of concrete with 3,000 Grade-low fineness slag are evaluated. Three conditions of concrete mixtures are considered considering workability, and the related durability tests are performed. Although the strength of concrete with 3,000 Grade slag is slightly lower than the OPC(Ordinary Portland Cement) concrete at the age of 28 days, but insignificant difference is observed in long-term compressive strength due to latent hydration activity. The durability performances in concrete with low fineness slag show that the resistances to carbonation and freezing/thawing action are slightly higher than those of concrete with high fineness slag, since reduced unit water content is considered in 3,000 Grade slag mixture. For the long-term age, the chloride diffusion coefficient of the 3000-grade slag mixture is reduced to 20% compared to the OPC mixture, and the excellent chloride resistance are evaluated. Compared with concrete with OPC and high fineness GGBFS, concrete with lower fineness GGBFS can keep reasonable workability and durability performance with reduced water content.

Skin Moisturizing Activity of Unripe Apple(Immature Fruit of Malus pumila) in Mice (풋사과 추출물의 피부 보습 효과)

  • Park, Hye Rim;Kim, Jae Kwang;Lee, Jae Kyoung;Choi, Beom Rak;Kim, Jong Dae;Ku, Sae Kwang;Jegal, Kyung Hwan
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.35 no.4
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    • pp.63-74
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    • 2022
  • Objectives : Skin aging is generally characterized by wrinkles, sagging, loss of elasticity roughness, pigmentation and dryness. This changes is caused by reducing the elements constituting the extracellular matrix contributing to the physiological properties of the skin, such as collagen fiber, elastic fiber, and hyaluronic acid. Adequate skin hydration is important to maintain normal skin function and reduce skin aging. The present study is objective to observe skin moisturizing effects of Unripe apple(UA, Immature fruit of Malus pumila Mill) in vivo and its underlying molecular mechanisms. Methods : ICR mice were orally administerd UA(100, 200 and 400mg/kg/day) for 8 weeks, and skin water contents and the expression of transforming growth factor (TGF)-𝛽1, ceramide, hyaluronan and collagen type I(COL1) were measured in dorsal back skin of the mice. Gene expression of hyaluronan synthase(HAS1, HAS2, HAS3), collagen synthase(COL1A1, COL1A2) and TGF-𝛽1 were also determined by realtime RT-PCR. Results : Skin water contents and the expression of TGF-𝛽1, ceramide, COL1 and hyaluronan were significantly increased in UA group(100, 200 and 400mg/kg/day) compared to vehicle control. The mRNA expression of HAS isoform(HAS1, HAS2, HAS3), COL1A1, COL1A2, and TGF-𝛽1 were also significantly increased by UA. Conclusions : UA has skin moisturizing effects and enhancement activities in skin function related components(COL1, hyaluronan, ceramide and TGF-𝛽1). These results suggested that UA can be a developing candidate for developing alternative skin protective agent or functional food ingredient.

Antibaterial Activity and Skin Moisturizing Effect of Cedrela sinensis A. Juss Shoots Extracts (참죽나무 새순 추출물의 항균 활성과 피부 보습효과에 관한 연구)

  • Kim, Sun-Young;Lee, Min-Hye;Jo, Na-Rae;Park, Soo-Nam
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.36 no.4
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    • pp.315-321
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    • 2010
  • In this study, we investigated the antibacterial activity and the skin moisturizing effect of cream contaning Cedrela sinensis A. Juss shoots extracts. MIC values of ethyl acetate fraction from Cedrela sinensis A. Juss shoots extracts on P. acnes and S. aureus were 0.13 %, 0.03% respectively and P. ovale and E. coli were 0.25 % equally. The results showed that the antibacterial activity of the ethyl acetate fraction on P. acnes and S. aureus were higher than the methyl paraben. The cream containing the ethyl acetate fraction from Cedrela sinensis A. Juss shoots extracts was formulated and its skin moisturizing effect was evaluated in a clinical trial. The skin hydration and transepidermal water loss (TEWL) were investigated after topical application of the cream. The skin hydrating effect of the cream containing Cedrela sinensis A. Juss shoots extract was 10 ~ 15 % higher than the placebo cream, and transepidermal water loss was decreased to 6.7 g/$m^2h$ in the subjects applied with cream containing the ethyl acetate fraction of Cedrela sinensis A. Juss shoots extracts. These results indicate that ethyl acetate fraction from Cedrela sinensis A. Juss shoots extracts could be applicable to new functional antibacterial cosmetics.

A Experimental Study on the Seawater Attack Resistance of Grouting Mixtures (내해수성 주입재 배합에 관한 실험적 연구)

  • Chun, Byungsik;Choi, Dongchan;Kim, Younghun;Kim, Jinchun
    • Journal of the Korean GEO-environmental Society
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    • v.11 no.1
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    • pp.53-59
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    • 2010
  • In seawater deposition condition, the corrosion and chemical attack of grouts are similar to those of concrete structure. Used in domestic MSG (Micro Silica Grouting) mixtured large amounts of silicate materials containing as cement powder is $8,000cm^2/g$ of the specific surface area or more due to the high hydration activity and high-strength, high durability, and features, $C_3A$ content of less than 5% to meet the standards chemical attack of seawater was evaluated as a cement material. Therefore, in this paper, with excellent seawater attack resistant MSG in combination with rapid hardening mineral was used, those of seawater characteristics were evaluated experimentally. Typically, sodium-silicate minerals or rapid hardening cements are used in domestic. About the homogel specimens with combination of MSG and rapid hardening agents for compressive strength, weight and length change characteristics were evaluated experimentally, and so we could present the excellent seawater resistant grouts combination.

Development of Specific Organ-Targeting Drug Delivery System (III)-In Vitro Study on Liver-Targeting Adriamycin Delivery System using Human Serum Albumin Microspheres- (장기표적용 약물수송체의 개발에 관한 연구(제 3보 -알부민 미립구를 이용한 Adriamycin의 간 표적용 수송체에 관한 in vitro 연구-)

  • Kim, Chong-Kook;Hwang, Sung-Joo;Yang, Ji-Sun
    • Journal of Pharmaceutical Investigation
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    • v.19 no.4
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    • pp.195-202
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    • 1989
  • In attempt to improve the chemotherapeutic activity of adriamycin, adriamycin-entrapped HSA microspheres were prepared and investigated by the various in vitro experiments. The shape, surface characteristics and size distribution of HSA microspheres are observed by scanning electron microscopy. The in vitro drug release, albumin matrix degradation by protease of HSA microspheres were studied. The shape of HSA microspheres were spherical and the surface was smooth and compact. The size of HSA microspheres ranged from 0.4 to $2.5\;{\mu}m$ and have average diameters of 0.5 to $0.7\;{\mu}m$. The size distribution of HSA microspheres prepared by ultrasonication was mainly affected by albumin concentration and heating time in the process of hardening. In in vitro, almost all adriamycin was released from HSA microspheres for 8 hr. Analysis of the resulting adriamycin release profiles demonstrated that adriamycin is released from the microspheres in two distinct steps, a fast phase (until 30 min) followed by a much slower sustained release phase. Drug release, which is due to diffusion, was depended on the rate of matrix hydration. Drug release was largely affected by albumin concentration and heating temperature during the process of hardening. Albumin matrix degradation of HSA microspheres was affected by heating temperature and albumin concentration. Higher temperature and longer times generally produce harder, less porous, and slowly degradable microspheres.

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Dyeing of Silk Fabric with Aqueous Extract of Cassia tora L. Seed - focusing on the mordanting and dyeing mechanisms - (결명자 색소 추출액에 의한 견직물 염색 -매염 및 염착 mechanism을 중심으로-)

  • Dho Seong Kook;Kang In A
    • Textile Coloration and Finishing
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    • v.17 no.2 s.81
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    • pp.10-18
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    • 2005
  • Silk fabrics mordanted with $Fe^{2+},\;Ni^{2+},\;and\;Cu^{2+}$ were dyed with the aqueous extract of Cassia tora L. seed which was known to include water soluble colorant kaempferol, one of flavonol compounds. Kaempferol can react with free radicals and chelate transition metal ions, which is thought to catalyze processes leading to the appearance of free radicals and have antioxidant activity. In relation to the coordinating and chelating mechanism of the ions with the silk protein and kaempferol, reasonable conclusions should be made on the colorant uptake and the water fastness of the fabric. The amount of the colorant on the fabric was in the order of $Fe^{2+}>Ni^{2+}>Cu^{2+}$. In case of dyeing through coordinaiton bonds between transition metal ions and silk protein and colorants, it was thought that the ions with the smaller secondary hydration shell, the higher preference to the atoms of the ligand coordinated, and the suitable bonding stability for the substitution of primarily hydrated water molecules for colorants led to the higher colorant uptake. The water fastnsess of the fabric was in the order of $Fe^{2+}>Cu^{2+}>Ni^{2+}$. It should be reasonable to choose transition metal ions with weak and strong tendency to the ionic and the coordination bond, respectively, to the carboxylate anion of the silk protein. Although further research needs to be done, the conclusions above may be generally applied to the natural dyeing through the coordination bond mechanism between transition metal ions and colorants and substrates.

Quality Characteristics of White Bread Amended with Rosa multiflora Thunberg Extracts with Inhibitory Activity against Helicobacter pylori (Helicobacter pylori 억제효과를 가지는 영실(Rosa multiflora Thunberg) 추출물을 첨가한 식빵의 품질특성)

  • Park, Ki Tae;Woo, Hi Seob;Cho, Young Je
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.41 no.10
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    • pp.1431-1440
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    • 2012
  • The optimum extraction of phenolic compounds from whole Rosa multiflora Thunberg fruits was accomplished using 70% ethanol, which produced extracts that generated a zone of inhibition around Helicobacter pylori of 13 mm when $200{\mu}g/mL$ phenolic compounds were applied. In this study, the quality of white bread baked from dough containing added Rosa multiflora Thunberg extracts was investigated. No deterioration of product quality factors including hydration of wheat flour, formation of dough and internal visual characteristics of dough was observed. However, white bread containing Rosa multiflora Thunberg extracts had a wet texture because of the high moisture level, as well as a high number of irregular bubble holes when compared to the control. Nevertheless, there were no remarkable differences between the sample and the control.

Formation of Illite in the Natural $K_2O-Al_2O_3-SiO_2-H_2O$ System in the Hydrothermal Clay Deposit of the Bobae Mine, Korea (보배광산의 열수변질 점토광상의 $K_2O-Al_2O_3-SiO_2-H_2O$계에서의 일라이트 형성)

  • Choo, Chang-Oh;Kim, Soo-Jin
    • Journal of the Mineralogical Society of Korea
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    • v.5 no.1
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    • pp.6-13
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    • 1992
  • Thermodynamic data of mineral reactions were used to construct a phase diagram for the formation of illite from andalusite at one bar and 325${\circ}C$ in the hydrothermal alteration. Based on chemical compositions, the free energy of formation of illite coexisting with andalusite was calculated by assuming the ideal mixing ina bunary system consisting of muscovite and pyrophyllite components. For illite with structural formula $K_{0.86}Al_{2.93}Si_{3.03}O_{10}(OH)_2$, its free energy of formation is -1147.727 kcal/mole at the condition under consideration. The stability area of illite is more narrow than that of end-member muscovite and prefers lower activity of silica. Illite was formed by hydration of andalusite while pyrophyllite decomposed. Illitization took place preferentially at margin and/or along fractures of andalusite.

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Fundamental Physical Properties of Cement Composites Containing Fineness Reject Ash (고분말 리젝트애시를 혼입한 시멘트복합체의 기본물성에 관한 연구)

  • Lee, Kang-Pil;Hong, Man-Gi;Lee, Sang-Soo;Song, Ha-Young
    • Journal of the Korea Institute of Building Construction
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    • v.11 no.4
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    • pp.363-370
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    • 2011
  • This study considerated reject ash, wastes of coal-fired power plants, to use mineral admixtures for cement. The pozzolan activity selected the fineness of the efficient reject ash through comparison and it compared to the fly ash that are widely used for concrete mixed material. Cement composites was prepared replacing of slag cement by fineness reject ash and fly ash, and properties of cement composites was tested by paste(setting time, fluidity, instrumental analysis) and mortar(compressive strength). Instrumental analysis results showed hydration reaction of fineness reject ash was not different from fly ash, but had more dense micro structures. Results of physical properties showed fineness reject ash shorten setting time, increased compressive strength compared by fly ash. Therefore using fineness reject ash with $6,000cm^2$/g to concrete mineral admixtures or cement composites was might be possible and could contribute to improve properties of concrete.

Evaluation of the Anti-Tumor Effects of Paclitaxel-Encapsulated pH-Sensitive Micelles

  • Han, Jong-Kwon;Kim, Min-Sang;Lee, Doo-Sung;Kim, Yoo-Shin;Park, Rang-Woon;Kim, Kwang-Meyung;Kwon, Ick-Chan
    • Macromolecular Research
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    • v.17 no.2
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    • pp.99-103
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    • 2009
  • We evaluated the efficacy of pH-sensitive micelles, formed by methoxy poly(ethylene glycol)-b-poly($\beta$)-amino ester) (PEG-PAE), as carriers for paclitaxel (PIX), a drug currently used to treat various cancers. PTX was successful encapsulated by a film hydration method. Micelles encapsulated more than 70% of the PTX and the size of the PTX-encapsulated micelles (PTX-PM) was less than 150 nm. In vitro experiments indicated that the micelles were unstable below pH 6.5. After encapsulation of PTX within the micelles, dynamic light scattering (DLS) studies indicated that low pH had a similar demicellization effect. An in vitro release study indicated that PTX was slowly released at pH 7.4 (normal body conditions) but rapidly released under weakly acidic conditions (pH 6.0). We demonstrated the safety of micelles from in vitro cytotoxicity tests on HeLa cells and the in vivo anti-tumor activity of PTX-PM in B16F 10 tumor-bearing mice. We concluded that these pH-sensitive micelles have potential as carriers for anti-cancer drugs.