• Title/Summary/Keyword: Swelling reaction

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Effect of High-Molecular Weight Organic Compounds on Improvement of Pore Structure of Cement Materials

  • Lee, Woong-Geol;Jeon, Se-Hoon;Song, Myong-Shin;Kim, Jusung
    • Journal of the Korean Ceramic Society
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    • v.56 no.6
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    • pp.534-540
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    • 2019
  • Carbon dioxide emissions involved in global warming are one of the most important issues in the world, and carbon dioxide emissions from the cement industry are about 7% of total carbon dioxide emissions. Thus, reduction in the amount of utilized cement can contribute to a reduction of carbon dioxide emissions. The average life of concrete is 20 ~ 30 years, and if concrete life can be improved by ten years, cement use will be much lower. In this study, we examined the use and effect of fructan from microbes as a method for the densification of the pore structure of cement. The effect of fructan on the hydration reaction and pore distribution, as well as the water absorption of hardened cement mortar were studied. Pores distribution increased in mesopore OPC, and absorption rate was found to decrease with the use of fructan, which has a glue-like and swelling character.

Structure-activity Relationships of 4-Senecioyloxymethyl-6,7-dimethoxycoumarin Analogues as Anti-Allergic Agents

  • Jeong, Hye-Gwang;Lee, Jee-Hyun;Jung, Sang-Hun;Han, Eun-Hee;Kim, Joo-Hwan;Kim, Dong-Hee;Jin, Mi-Rim;Siripuram, Praveen Kumar;Choi, Yong-Seok;Song, Gyu-Yong
    • Bulletin of the Korean Chemical Society
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    • v.28 no.10
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    • pp.1725-1728
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    • 2007
  • Mast cells are key effector cells in the early phase allergic inflammation and in diverse immunological and pathological processes. In order to understand the effect on reduction of the anti-dinitrophenyl (DNP) IgE antibody-induced β-hexosaminidase release in RBL-2H3 rat mast cells, a novel series of 4-senecioyloxymethyl- 6,7-dimethoxycoumarins (SMDC) was prepared by reacting 4-chloromethyl-6,7-dimethoxycoumarin with various carboxylic acids. Compounds 8-11 with cyclic moiety such as phenyl, thiophenyl, pyridinyl, and furanyl group were found to inhibit-hexosaminidase release more potently (5.98-9.62 μM) than compounds 3- 7 and 12 with acyclic moiety (19.32-76.78 μM). Furthermore, compounds 8 and 9 inhibited IgE-induced ear swelling and significantly reduced systemic passive cutaneous anaphylaxis reaction in mice.

The Adsorption Characteristics of Heavy Metals by Acrylic Fibers Treated with Hydroxylamine (II) - Properties of Cu(II) Adsorption and its Chelates - (하이드록실 아민으로 처리한 아크릴 섬유의 중금속 흡착특성 (II) -구리 (II)흡착과 그 키일레이트의 성질-)

  • Chin Young-gil;Choi Suk-chul
    • Journal of the Korean Society of Clothing and Textiles
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    • v.13 no.2 s.30
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    • pp.128-136
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    • 1989
  • In order to investigate a practical application of fibrous adsorbents to heavy metal ions, amidoxime fibers, as a particular class of solid chelate agents, were prepared by hydroxylamine treatment for acrylic fibers in a recipe of neutralization. Among the important problems from plant effluents are toxic concentrations of heavy metals such as copper. Accordingly, the properties of Cu (II) adsorption and its chelates were studied. The results obtained are as follows; The fibrous adsorbents have the property of increasing the swelling volumes by amidoximation. The adsorption of Cu (II) ion is characterized by an endothermic reaction, which is estimated as the plus values in the enthalpy change ($\delta$H=1.30 Kcal/mol. and 3.14 Kcal/mol.). The Cu (II) ions are adsorbed in the range of pH $3\~8$ and the maximum adsorptions are occurred about pH 8. Owing to the anions $(NO_3^-,\;Cl^-)$ of copper salts, amidoxime fibers form 1:1 and 2:1 (ligand: metal) chelating complexes with Cu (II). The nitrate anion chelates to amide I (NH) of amidoxime groups and the chlorine anion does to nitrosyl (NO). These effects relate to the crystallization of the complex and the thermal property.

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Preparation of Surface-anionized Poly(vinyl alcohol-co-methacrylic acid) Hydrogel Beads (표면에 음이온이 도입된 폴리(비닐 알코올-co-메타아크릴산) 하이드로젤 입자의 제조)

  • 윤주표;박연흠;이세근;박기홍;이철주
    • Polymer(Korea)
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    • v.27 no.2
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    • pp.159-166
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    • 2003
  • For the purpose of obtaining surface-anionized poly(vinyl alcohol) (PVA) hydrogel beads, vinyl acetate(VAc) and methacrylic acid(MMA) were copolymerized by the suspension polymerization technique and followed by the saponification. It was confirmed by $^1$H-NMR that the copolymerized microspheres contained carboxylic acid groups in their surface. poly(VAc-co-MAA) microspheres were completely saponified in the heterogeneous system. The saponification reaction was laster than that of PVAc microspheres. We observed the swelling property of saponified PVA microspheres treated in the acidic solution and in the alkaline solution successively. Saponified microspheres shrank in acidic solution and swelled in alkaline solution respectively, which was reversible. from the result, saponified microspheres were highly water-absorbing hydrogel beads and were certified -COOH group at their surface by $^1$H-NMR and FT-IR.

Comparison of Immuno-Suppressive Activities of Pinitol Isolated from Soybean (콩으로부터 추출한 Pinitol의 면역억제 활성 비교)

  • Park, Chul-Hong;Heo, Jin-Chul;Nam, Dong-Yun;Lee, Si-Rim;Nam, So-Hyun;Son, Min-Sik;Hwang, Young-Hyun;Lee, Sang-Han
    • Food Science and Preservation
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    • v.16 no.3
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    • pp.449-453
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    • 2009
  • The experiment was conducted to validate anti-inflammatory effects of pinitol from bean. It was evaluated for some molecule targets by wound healing assay and RT-PCR. The results of wound healing assay was shown dose-dependent inhibition of cell migration in cancer cells and inhibited RNA expression of ICAM-1, CD 44, MMP-17, MMP-14 and ARF2. Immune suppression activity in a mouse provoked by DNFB observed that inflammatory reaction with pinitol were reduced ear swelling and inflammatory cells infiltration in mouse atopic models. The result confirmed that pinitol have the effect of dose-dependent immune suppression activity.

Membrane behavior of bentonite-amended compacted clay towards Zn(II) and Pb(II)

  • Tang, Qiang;Katsumi, Takeshi;Inui, Toru;Li, Zhenze
    • Membrane and Water Treatment
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    • v.6 no.5
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    • pp.393-409
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    • 2015
  • Zinc and lead pollution are public environmental issues that have attracted lots of attention for a long time. Landfill leachate contains heavy metals, such as Zn(II) and Pb(II), which are usually related to the pollution of groundwater, especially in developing countries. Bentonite has been proven to be effective in enhancing the membrane property of clay, by which landfill liners can have better barrier performance towards the migration of contaminants. In this study, 5% sodium bentonite amended with locally available Fukakusa clay was utilized to evaluate the membrane behavior towards the heavy metals zinc and lead. The chemico-osmotic efficiency coefficient, ${\omega}$, was obtained through Zn(II) and Pb(II) solutions with different concentrations of 0.5, 1, 5, 10, and 50 mM. According to the results, ${\omega}$ continually decreased as the Zn(II) and Pb(II) concentrations increased, which is consistent with the Gouy-Chapman theory. Compared to normal inorganic ions, the membrane behavior towards heavy metal ions was lower. The migration of heavy metal ions was not observed based on experimental results, which can be attributed to the adsorption or ion exchange reaction. The mechanisms of the membrane performance change were discussed with the assistance of XRD patterns, free swelling results, XRF results, and SEM images.

Albumin Release from Biodegradable Hydrogels Composed of Dextran and Poly(Ethylene Glycol) Macromer

  • Kim, In-Sook;Jeong, Young-Il;Kim, Do-Hoon;Lee, Yun-Ho;Kim, Sung-Ho
    • Archives of Pharmacal Research
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    • v.24 no.1
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    • pp.69-73
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    • 2001
  • Biodegradable hydrogels based on glycidyl methacrylate dextran (CMD) and dimethacrylate poly(ethylene glycol) (DMP) were proposed for colon-specific drug delivery. GMD was synthesized by coupling of glycidyl methacylate with dextran in the presence of 4-(N, N-dimethylamino)pyridine (DMAP) using dimethylsulfoxide as a solvent. Methacrylate-terminated poly (ethylene glycol) (PEG) macromer was prepared by the reaction of PEG with methacryloyl chloride. CMD/DMP hydrogels were prepared by radical polymerization of phosphate buffer solution (0.1 M, pH 7.4) of GMD and DMP using ammonium peroxydisulfate (APS) and UV as initiating system. The synthetic GMD, DMP and GMD/DMP hydrogels were characterized by fourier transform infrared (FT-lR) spectroscopy. The FITC-albumin loaded hydrogels were prepared by adding FITC-albumin solution before UV irradiation. Swelling capacity of GMD/DMP hydrogels was controlled not only by molecular weight of dextran, but also by incorporation ratio of DMP Degradation of the hydrogels has been studied in vitro with dextranase. FITC-albumin release from the GMD/DMP hydrogels was affected by molecular weight of nextran and the presence of dextranase in the release medium.

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Supraclavicular BCG Lymphadenitis Noted at 21 Months after BCG Vaccination Confirmed by a Molecular Method (분자생물학적 방법으로 확진한 접종 21개월 후에 발생한 BCG 쇄골상부 림프절염 1례)

  • Lee, Min Hyun;Chae, Moon-Hee;Park, Kyoung Un;Cho, Hye-Kyung
    • Pediatric Infection and Vaccine
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    • v.21 no.2
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    • pp.139-143
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    • 2014
  • Bacille Calmette-$Gu\acute{e}rin$ (BCG) lymphadenitis is the most common complication of BCG vaccination. It commonly occurs in infants aged <6 months involving ipsilateral axillary lymph nodes. We described BCG lymphadenitis in a 22-month-old boy presenting swelling of left supraclavicular lymph node that was confirmed by real-time polymerase chain reaction (PCR) and the multiplex PCR targeting the region of difference (RD).

Histopathological changes in lymphoid organs of chickens inoculated with IBDV (SBV92) (IBDV (SH/92)의 인공감염에 의한 닭 면역장기의 병리조직학적 연구)

  • 엄성심;김범석;임채웅;임병무;이호일;정동석
    • Korean Journal of Veterinary Service
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    • v.22 no.3
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    • pp.247-255
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    • 1999
  • Sequential morphologic changes in the lymphoid organs were examined after ocular and cloacal inoculation in 3weekold chicks with a highly virulent strain (SH/92) of infectious bursal disease virus (IBDV). The infected chickens were sacrificed at 6, 12, 24, 48, 72, and 96 hrs post inoculation (Pl), and thymus, harderian gland, ceacal tonsil, and spleen were observed. Histologically, the significant lesions were characterized by lymphocyte depletion and the earliest detectable changes were evident at 12 hrs Pl. In thymic cortex, lymphoid depletion with apoptosis and prominent "tingible body macrophages" were observed. As the infection advanced, the lesions showed more severe changes. Dying cells were characterized either by capping of nuclear chromatin (apoptosis) or by cytoplasmic swelling (necrosis). In situ staining for apoptosis, some lymphoid cells revealed typical positive reaction, even the stainability was variable depend on every lymphoid organs. These results suggest that IBBV (SH/92) cause severe damage both primary and secondary lymphoid organs, and both T and B lymphocytes. Also the lymphoid depletion of these organs is caused by necrosis and apoptosis induced by IBDV.d by IBDV.

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Biocompatibility of oxidized alginate/gelatin/BCP -based hydrogel composites

  • Phuong, Nguyen Thi;Min, Young-Ki;Yang, Hun-Mo;Song, Ho-Yeon;Lee, Byong-Teak
    • Proceedings of the Materials Research Society of Korea Conference
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    • 2010.05a
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    • pp.40.2-40.2
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    • 2010
  • In this study, oxidized alginate/gelatin/biphase calcium phosphate (BCP)- based hydrogel composites were fabricated. Alginate sodium was oxidized by periodate. The oxidized product was confirmed by using $^1H$ and $^{13}C$ NMR spectra. The number average molecular weight ($M_n$), the average molecular weight ($M_w$) of the oxidized alginate were determined by Gel Permeation Chromatography (GPC). The hydrogel was formed from the oxidized alginate and gelatin solution via Schift-base reaction. The hydrogel showed a highly porosity by a Scanning Electron Microscope (SEM) and Mercury Intrusion Porosimetry (MIP). Crosslinked density of the gel matrix were assessd by trinitrobenzene sulfonic acid (TNBS) assay that shows a high effect on swelling ratio. Increment of the crosslinked desity resulted in enhancing compressive strength of the hydrogel composite. The cytotoxity of hydrogel was assessed with osteoblast MG-63. The hydrogel composites show a high compatibility. The obtained results showed a potential application for bone regeneration in future.

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