• Title/Summary/Keyword: Complex permeability

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Anti-arthritic Effect of a New Diet-Supplement Containing Red Ginseng Extract and Glucosamine Complex (홍삼추출물과 글루코사민 복합제제의 관절염에 미치는 영향)

  • Jeong, Choon-Sik;Hyun, Jin-Ee;Kang, Min-Hee;Sim, Joon-Soo;Son, Mi-Jin;Jung, Sang-Hoon;Kim, Jong-Hoon;Lee, Kwang-Seong;Kim, Yeong-Shik
    • Korean Journal of Pharmacognosy
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    • v.34 no.4 s.135
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    • pp.327-334
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    • 2003
  • We evaluated the anti-arthritic effect of a new diet-supplement product containing red ginseng, glucosamine, shark cartilage, ascorbic acid and manganese chloride for the relieving arthritic symptoms. Anti-inflammatory activities of the aqueous extract of red ginseng (250 and 500 mg/kg), glucosamine (240 mg/kg) and shark cartilage (240 mg/kg) were tested individually on vascular permeability and carrageenan-induced paw edema. Glucosamine and shark cartilage showed the inhibition of vascular permeability by 29.6 and 32.9%, respectively. Red ginseng (500 mg/kg) and shark cartilage showed the inhibition of carrageenan-induced paw edema at 0.5, 1, 2 and 3 hr. The supplement (red ginseng mixture: RGM) composed of red ginseng (43.5%), glucosamine (25.0%), shark cartilage (25.0%), ascorbic acid (5.0%) and manganese chloride (1.5%) was prepared and its inhibitory activities including vascular permeability and carrageenan-induced paw edema were comparable to anti-inflammatory drugs such as diclofenac and ibuprofen. It was also tested on adjuvant-induced arthritis in rats as one of chronic arthritic tests and Randall-Selitto assay as an analgesic test. RGM showed the inhibition against the swelling of rat paws induced by Mycobacterium tuberculosis at a dose of 1,500 mg/kg. Determination of cytokines of the sera sampled from arthritis-induced animals indicated that RGM increased the levels of $interferon-{\gamma}$ and interleukin-6, representing the immunostimulatory effect by red ginseng. RGM treatment moderately reduced the production of NO in RAW 264.7 cells in a dose-dependent manner. Taken together, these results support that RGM can be applicable for the improvement of arthritic as a new diet-supplement.

Effects of Sheet Thickness on Electromagnetic Wave Absorption Characteristics in FeSiCr/Polymer Composite Sheets (FeSiCr/폴리머 복합 시트의 전자파 흡수 특성에 미치는 시트 두께의 영향)

  • Noh, Tae-Hwan;Kim, Ju-Beom
    • Journal of the Korean Magnetics Society
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    • v.20 no.4
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    • pp.143-148
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    • 2010
  • This study examined the effects of sheet thickness on electromagnetic wave absorption characteristics and internal microstructure in 92.6%Fe-6.5%Si-0.9%Cr (wt%) alloy flakes/polymer composite sheets available for quasi-microwave band. The composite sheets with the thickness of 0.3, 0.4 and 0.5 mm were prepared by tape casting. A significant decrease in transmission parameter $S_{21}$ and a large increase in power loss were observed for the thick composite sheet in the frequency range of 1~5 GHz. However the permeability properties were not affected by thickness variation, while the imaginary part of complex permittivity increased with the increase of sheet thickness at 1~5 GHz. The enhanced electromagnetic wave absorption characteristics in the thicker composite sheets was attributed to the changed microstructure and the higher dielectric loss.

Heat Transfer and Pressure Drop Characteristics of a Horizontal Channel Filled with Porous Media (다공성매질을 삽입한 수평채널의 열전달 및 압력강하 특성)

  • Son, Young-Seok;Shin, Jee-Young;Cho, Young-Il
    • Journal of Advanced Marine Engineering and Technology
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    • v.33 no.2
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    • pp.244-251
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    • 2009
  • Porous media have especially large surface area per volume, which contain complex fluid passage. If porous media can be applied to cool a CPU or an electronic device with large heat dissipation, it could result in heat transfer enhancement due to the enlargement of the heat transfer area and the flow disturbance. This study is aimed to identify the heat transfer and pressure drop characteristics of high-porosity metal foams in a horizontal channel. Experiment is performed with the various heat flux, velocity and pore density conditions. Permeabilities, which is deduced from Non-Darcy flow model, become lower with increasing pore density. Nusselt number also decreases with higher pore density. High pore density with same porosity case shows higher pressure loss due to the increase of surface area per unit volume. The fiction factor decreases rapidly with increase of Reynolds number in Darcy flow region. However, it converges to a constant value of the Ergun coefficient in Non-Darcy flow region.

Electical and Electomagnetic wave Absorbing Properties of MnZn Ferrite-Rubber Composites in Microwave Frequencies (MnZn계 페라이트-고무 복합체의 마이크로파대역에서의 전기적 특성 및 전자파 흡수 특성)

  • 김호철;이병택;정연춘;엄진섭
    • The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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    • v.4 no.2
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    • pp.41-47
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    • 1993
  • Electrical and electromagnetic wave absorbing properties of MnZn ferrite-rubber composites have been examined for varying the volume fraction of ferrite powder from 0.1 to 0.4 in the frequency range between 1-10 GHz. As the volume fraction of MnZn ferrite increased, the complex permittivity and permeability of composite increased. The peak of reflection loss at the frequency corresponding to 1/4 wavelength shifts to lower frequency, and shifts to lower frequency as the thickness of absorber increased. We show that for the ferrite-rubber composites the volume fraction of ferrite should be controled to obtain the absorbing properties required in given frequency range.

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The Effect of Oleic Acid and Propylene Glycol on the Electrical Properties of Skin (올레인산 및 프로필렌글리콜이 피부의 전기적 성질에 미치는 영향)

  • Oh, Seaung-Youl;Guy, Richard H.
    • Journal of Pharmaceutical Investigation
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    • v.24 no.4
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    • pp.281-287
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    • 1994
  • The effects of oleic acid, propylene glycol and 5% (w/w) oleic acid in propylene glycol on the electrical properties of hairless mouse skin were studied and the results were compared. The complex electrical impedance was measured as a function of frequency, and resistance and capacitance were determined from the Nyquist plot. Immediately after the treatment with oleic acid, resistance was 145% of the pretreatment value. However it decreased with time and, after 20 hours, it was about 25% of its pretreatment value. Capacitance increased; immediately after the treatment, it was about 125% of pretreatment value and it seemed to increase slowly with time. When the skin was treated with propylene glycol, resistance decreased about 5O% and capacitance increased about 65%. Similar results were observed when the skin was treated with 5% (w/w) oleic acid in propylene glycol, except that the magnitude of resistance drop was much larger. Oleic acid acted synergistically with propylene glycol. Together with the flux data in the literature, the results obtained in this work indicate that electrical resistance is closely related to the permeability of drug molecules through the skin. The results are discussed in terms of the mechanism of action of these penetration enhancers. Overall, this work provided further mechanistic insight into the role of SC lipids in skin resistance and capacitance.

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A Study on Natural Dyeing using Caesalpinia sappan -Mordanting Effect of Rice Straw Ash Solution- (소목 천연 염색에 관한 연구 II -잿물의 매염효과에 대하여-)

  • Kwon Min-Soo;Choi In-Ryu;Kim Jong-Jun;Jeon Dong-Won
    • The Research Journal of the Costume Culture
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    • v.12 no.6 s.53
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    • pp.908-917
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    • 2004
  • In the previous article, the effect of aluminum compounds on the mordanting of the Caesalpinia sappan L. dyeing was studied. According to the type of the compound, the effect on the dyeing was found to be different even if $Al^{3+}$ ion was present in the molecular structure of the compound. It was postulated that there would be complex effects other than the effects based on the purified Al compounds only, since there are some amount of compounds hard to neglect. In order to reproduce the traditional dyeing practice, rice straw ash solutions were prepared as mordanting agents. The pH values of the solution baths were 4, 5, 6, 9, and 11 in order to investigate the pH effect on the color development by adding appropriate amount of Schizandra chinensis extract solution. The inherent dyeing properties were evaluated by the analysis of color difference, air permeability, the characteristics developed by pre-mordanting, post-mordanting, or simultaneous mordanting methods.

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A Study on the Drape Profile Analysis of the Apparel Textiles and 3D Virtual Textiles using a 3D Digital Clothing Software (3D 가상패션소재의 드레이프성 연구 - 3D 의상 CAD 시스템 활용 -)

  • Lee, Yoon-Ju;Kim, Jong-Jun
    • Journal of Fashion Business
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    • v.15 no.5
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    • pp.103-114
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    • 2011
  • During a wearer's movement, the apparel fabric layers collide each other in a highly complicated manner. The collision involves cloth-cloth, and cloth-body collision. The diversity of the textile fabrics, including silk, wool, cotton, and other synthetic fibers, together with the complex details of the apparel construction, makes the collision and other calculation procedure involved in the 3-dimensional clothing software system much more complicated. Therefore, there is a need to measure the behavior of the fabrics during the fabric collision cycles. In this study, as a first step, static measurements pertinent to the factors governing the appearance of the apparel fabrics were implemented. The drape profile, stiffness(Sd and Sf), tensile properties, thickness, and the air permeability were measured. The correlation between the parameters were calculated and reviewed. It is found that there is a high correlation of 0.97 between the actual fabric drape parameters and the 3D virtual fabric drape parameters. The measured drape coefficients of the fabrics show relatively good correlation with the measured fabric stiffness.

Preparation and Characterization of Nanofibrous Membranes of Poly(D,L-lactic acid)/Chitin Blend for Guided Tissue Regenerative Barrier

  • Kim, Hong-Sung;Kim, Jong-Tae;Jung, Young-Jin;Hwang, Dae-Youn;Son, Hong-Joo;Lee, Jae-Beom;Ryu, Su-Chak;Shin, Sang-Hun
    • Macromolecular Research
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    • v.17 no.9
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    • pp.682-687
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    • 2009
  • Nanofibrous membranes of poly(D,L-lactic acid)/chitin blend were prepared by electro spinning for a barrier of guided tissue regeneration. A miscible solution was obtained by the blending chitin-salt complex into 1-methyl-2-pyrrolidone solution of poly(D,L-lactic acid). The properties of the blend were examined for nanofibrous fabrication. The viscosity of the blend solution was increased significantly due to chain entanglement despite the low ratio of chitin to poly(D,L-lactic acid). An interaction between two polymeric compositions was confirmed by Fourier transform infrared spectroscopy. X-ray diffraction detected an appreciably ordered microstructure in the nanofiber of the blend. A membrane of thinner nanofibers was fabricated by electro spinning the chitin blend. The permeability of the membranes was examined using bioactive model compounds.

A novel method of surface modification to polysulfone ultrafiltration membrane by preadsorption of citric acid or sodium bisulfite

  • Wei, Xinyu;Wang, Zhi;Wang, Jixiao;Wang, Shichang
    • Membrane and Water Treatment
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    • v.3 no.1
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    • pp.35-49
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    • 2012
  • In membrane processes, various agents are used to enhance, protect, and recover membrane performance. Applying these agents in membrane modification could potentially be considered as a simple method to improve membrane performance without additional process. Citric acid (CI) and sodium bisulfite (SB) are two chemicals that are widely used in membrane feed water pretreatment and cleaning processes. In this work, preadsorptions of CI and SB were developed as simple methods for polysulfone ultrafiltration membrane modification. It was found that hydrogen bonding and Van Der Waals attraction could be responsible for the adsorptions of CI and SB onto membranes, respectively. After modification with CI or SB, the membrane surfaces became more hydrophilic. Membrane permeability improved when modified by SB while decreased a little when modified by CI. The modified membranes had an increase in PEG and BSA rejections and better antifouling properties with higher flux recovery ratios during filtration of a complex pharmaceutical wastewater. Moreover, membrane chlorine tolerance was elevated after modification with either agent, as shown by the mechanical property measurements.

Development of fracture face mapping algorithm and its applications to the design of various engineering and environmental works. (토목설계 및 시공분야 지반조사를 위한 절리 단면 영상법 개발 및 그의 응용사례)

  • 김중열;김유성;김기석
    • Proceedings of the Korean Geotechical Society Conference
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    • 2002.03a
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    • pp.119-126
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    • 2002
  • Fractures, especially faults have most significant influence on the difficulties encountered in various engineering and mining works, because they can give rise to inevitable reductions in shear strength as well as large increase in permeability. Thus, before underground access is possible, it is desirable to estimate the distribution and geometry of fractures in advance, if reliable structural data from e.g. Televiewer tool are available. To this end, fracture face mapping is just the evaluation method used to form a fracture image determined by intersecting of each fracture plane with a selected plane section of a rock mass, assuming that all fractures be planar with fixed-aperture. Although many fractures are geometrically complex and others are altered chemically, according to the abundant experiments in recent years, it would seem that the technique could be applied to benefit the design of numerous engineering works such as slope stability, tunnel excavations, dam foundation and diverse environmental works. This paper presents at first an evaluation algorithm for fracture face mapping and then concludes with various representative examples of applications.

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