• Title/Summary/Keyword: Mixed Compound

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Agonist-Antagonist Effects of Buprenorphine on Action Potentials of Frog Sciatic Nerve Fibers (개구리 좌골신경에 대한 Buprenorphine의 작용 양상)

  • Lee, Jong-Hwa;Frank, George B.
    • The Korean Journal of Pharmacology
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    • v.25 no.1
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    • pp.23-30
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    • 1989
  • Buprenorphine, one of the mixed agonist-antagonist opioid drugs was used to inverstigate the opioid receptor on frog sciatic nerve A fibers. Action potentials were recorded for 4 hrs by a sucrose gap apparatus which were separated by four rubber membranes. To examine the one of the mechanism of action of buprenorphine, meperidine or naloxone was added after or before the treatment of buprenorphine. The results of this experiment were as follows: 1. Buprenorphine suppressed significantly the compound action potentials of frog sciatic nerve, and the maximal effects were shown both at $10^{-4}\;M$ and at $10^{-8}\;M$. 2. The dose-response relationship of buprenorphine on the depressant effect in frog sciatic nerve was biphasic and inverted U-shaped. 3. Buprenorphine blocked the effect of Meperidine $(10^{-3}\;M)$ on this preparation. 4. The depressant effcct of Buprenorphine on frog sciatic nerve was blocked by $10^{-8}\;M$ naloxone. From the above results, buprenorphine acts as one of agoinist-antagonistic effect on frog sciatic nerve, and the opioid receptor on this preparation is located on or near the intracellular opening of the sodium channels, which are sensitive to naloxone.

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Removal of RDX using Lab-scale Plug Flow Constructed Wetlands Planted with Miscanthus sacchariflorus (Maxim.) Benth (물억새를 식재한 플러그 흐름 습지에서의 RDX 제거동역학)

  • Lee, Ahreum;Kim, Bumjoon;Park, Jieun;Bae, Bumhan
    • Journal of Soil and Groundwater Environment
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    • v.20 no.6
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    • pp.85-94
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    • 2015
  • RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) is the most important explosive contaminant, both in concentration and in frequency, at military shooting ranges in which green technologies such as phytoremediation or constructed wetlands are the best option for mitigation of explosive compounds discharge to the environment. A study was conducted with two identical lab-scale plug flow constructed wetlands planted with Amur silver grass to treat water artificially contaminated with 40 mg/L of toxic explosive compound, RDX. The reactor was inoculated with or without RDX degrading mixed culture to evaluate plant-microorganism interactions in RDX removal, transformation products distribution, and kinetic constants. RDX and its metabolites in water, plant, and sediment were analyzed by HPLC to determine mass balance and kinetic constants. After 30 days of operation, the reactor reached steady-state at which more than 99% of RDX was removed with or without the mixed culture inoculation. The major transformation product was TNX (Trinitroso-RDX) that comprised approximately 50% in the mass balance of both reactors. It was also the major compound in the plant root and shoot system. Acute toxicity analysis of the water samples showed more than 30% of toxicity reduction in the effluent than that of influent containing 40 mg/L of RDX. In the Amur silver grass mesocosm seeded with the mixed culture, the specific RDX removal rate, that is 1st order removal rate normalized to plant fresh weight, was estimated to be 0.84 kg−1 day−1 which is 16.7% higher than that in the planted only mesocosm. Therefore, the results of this study proved that Amur silver grass is an effective plant for RDX removal in constructed wetlands and the efficiency can be increased even more when applied with RDX degrading microbial consortia.

Effects of Ball Milling Condition on Sintering of Cu, Zn, Sn and Se Mixed Powders (Cu, Zn, Sn, Se 혼합 분말의 소결특성에 미치는 볼밀링 영향)

  • Ahn, Jong-Heon;Jung, Woon-Hwa;Jang, Yun-Jung;Lee, Seong-Heon;Kim, Kyoo-Ho
    • Journal of Powder Materials
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    • v.18 no.3
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    • pp.256-261
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    • 2011
  • In order to make a $Cu_2ZnSnSe_4$ (CZTSe) sputtering target sintered for solar cell application, synthesis of CZTSe compound by solid state reaction of Cu, Zn, Sn and Se mixed powders and effects of ball milling condition on sinterability such as ball size, combination of ball size, ball milling time and sintering temperature, was investigated. As a result of this research, sintering at $500^{\circ}C$ after ball milling using mixed balls of 1 mm and 3 mm for 72 hours was the optimum condition to synthesis near stoichiometric composition of $Cu_2ZnSnSe_4$ and to prepare sintered pellet with high density relatively.

Degradation of Phenanthrene by Bacterial Strains Isolated from Soil in Oil Refinery Fields in Korea

  • KIM JEONG DONG;SHIM SU HYEUN;LEE CHOUL GYUN
    • Journal of Microbiology and Biotechnology
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    • v.15 no.2
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    • pp.337-345
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    • 2005
  • The degradation of phenanthrene, a model PAH compound, by microorganisms either in the mixed culture or individual strain, isolated from oil-contaminated soil in oil refmery vicinity sites, was examined. The effects of pH, temperature, initial concentration of phenanthrene, and the addition of carbon sources on biodegradation potential were also investigated. Results showed that soil samples collected from four oil refinery sites in Korea had different degrees of PAH contamination and different indigenous phenanthrene-degrading microorganisms. The optimal conditions for phenanthrene biodegradation were determined to be 30$^{circ}C$ and pH 7.0. A significantly positive relationship was observed between the microbial growth and the rate of phenanthrene degradation. However, the phenanthrene biodegradation capability of the mixed culture was not related to the degree of PAH contamination in soil. In low phenanthrene concentration, the growth and biodegradation rates of the mixed cultures did not increase over those of the individual strain, especially IC10. High concentration of phenanthrene inhibited the growth of microbial strains and biodegradation of phenanthrene, but was less inhibitory on the mixed culture. Finally, when non-ionic surfactants such as Brij 30 and Brij 35 were present at the level above critical micelle concentrations (CMCs), phenanthrene degradation was completely inhibited and delayed by the addition of Triton X100 and Triton N101.

Bioconversion of Ginsenoside Rb1 to Compound K using Leuconostoc lactis DC201

  • Piao, Jin-Ying;Kim, Yeon-Ju;Quan, Lin-Hu;Yang, Dong-Uk;Min, Jin-Woo;Son, Seon-Heui;Kim, Sang-Mok;Yang, Deok-Chun
    • Korean Journal of Plant Resources
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    • v.24 no.6
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    • pp.712-718
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    • 2011
  • Ginseng (Panax ginseng) is frequently used in Asian countries as a traditional medicine. The major components of ginseng are ginsenosides. Among these, ginsenoside compound K has been reported to prevent the formation of malignancy and metastasis of cancer by blocking the formation of tumor and suppressing the invasion of cancer cells. In this study, ginsenoside $Rb_1$ was converted into compound K, via secreted ${\beta}$-glucosidase enzyme from the Leuconostoc lactis DC201 isolated, which was extracted from Kimchi. The strain DC201 was suspended and cultured in MRS broth at $37^{\circ}C$. Subsequently, the residue from the cultured broth supernatant was precipitated with EtOH and then dissolved in 20 mM sodium phosphate buffer (pH 6.0) to obtain an enzyme liquid. Meanwhile, the crude enzyme solution was mixed with ginsenoside $Rb_1$ at a ratio of 1:4 (v/v).The reaction was carried out at $30^{\circ}C$ and 190 rpm for 72 hours, and then analyzed by TLC and HPLC. The result showed that ginsenoside Rb1 was transformed into compound K after 72 hours post reaction.

The Type and Characteristics of the Clouds-Shaped Pattern (조선시대 직물에 나타난 구름문양의 유형과 특성)

  • Jang, Hyun-Joo
    • Fashion & Textile Research Journal
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    • v.6 no.2
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    • pp.169-176
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    • 2004
  • The clouds-shaped pattern is originated from Taoism, Buddhism, and Confucianism. It stands for good-luck, longevity and productivity. It has been used on its own or with other patterns since the ancient times. It also has various forms. It particularly was used more frequently than any other patterns as a typical good-luck pattern, representing auspiciousness, divine authority, and so on in Chosun dynasty. The pattern, according to its component parts, is classified as individual type and compound type, which is mixed with other patterns such as treasure pattern, plant pattern, letter pattern, or animal pattern. For both individual type and compound type, swastika-shaped cloud pattern was mostly used. For compound type, the pattern compounded of treasure pattern was extraordinarily used a lot. In terms of the arrangement, the most common arrangement methods were brick-shaped arrangement and dense type arrangement, the arrangement method that spreads the patterns all over the surface. Among the fabrics with clouds-shaped pattern, satin damask fabrics had the majority. Clouds-shaped pattern was used a lot in men's Po(coat), such as Dahnryoung, Jiknyoung, Chollik, etc. rather than in women's clothes. It was a typical pattern used in Dahnryoung, an official uniform that represented people in the highest class in Chosun dynasty. The divine power symbol of this pattern indicated the authority and dignity that the upper class people could have.

Characteristics of $Cu_2ZnSnSe_4$ Thin Film Solar Absorber Prepared by PLD using Solid Target (광흡수층 적용을 위한 PLD용 $Cu_2ZnSnSe_4$ 타겟 제조와 증착 박막의 특성)

  • Jung, Woon-hwa;Rachmat, Adhi Wibowo;Kim, Kyoo-ho
    • 한국신재생에너지학회:학술대회논문집
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    • 2009.06a
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    • pp.130-133
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    • 2009
  • $Cu_2ZnSnSe_4$(CZTSe) is one of the promising materials for the solar cell due to its abundant availability in the nature. In this study, we report the fabrication of CZTSe thin film by Pulsed Laser Deposition(PLD) method using quaternary compound target on sodalime glass substrate. The quaternary CZTSe compound target was synthesized by solid state reaction method using elemental powders of Cu, Zn, Sn and Se. Powders were milled in high purity ethanol using zirconia ball with mixed size of 1 and 3 mm at the same proportions for 72 hours milling time. The structural, chemical and mechanical properties of the synthesized CZTSe powders were investigated prior to the deposition process. The CZTSe compound powder, and $500^{\circ}C$ of sintering temperature shows the best properties for PLD target. Results show that the as-deposited CZTSe thin films with the precursors by PLD have a composition near-stoichiometric.

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DISSIMILAR FRICTION-STIR WELDING OF ALALLOY 1050 AND MGALLOY AZ31

  • Park, Seung Hwan C.;Masato Michiuchi;Yutaka S. Sato;Hiroyuki Kokawa
    • Proceedings of the KWS Conference
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    • 2002.10a
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    • pp.534-538
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    • 2002
  • Dissimilar friction stir welding of aluminum (AI) alloy 1050 and magnesium (Mg) alloy AZ31 was successfully done in the limited welding parameters. The dissimilar weld showed good quality and facility compared to conventional fusion weld. Transverse cross section perpendicular to the welding direction had no defects. The weld was divided into base material of Al alloy, an irregular shaped stir zone and base material of Mg alloy. The irregular shaped stir zone was roughly located around the initial weld center. The weld interface near plate surface shifted from initial weld centerline to the advancing side. Hardness profile of the weld was heterogeneous, and the hardness value of the stir zone was raised to about 150 Hv to 250 Hv. The mixed phase was identified to intermetallic compound $Mg_{17}$Al$_{12}$ using x-ray diffraction method, energy dispersive x-ray spectroscopy (EDX) and electron probe micro analysis (EPMA). The formation of intermetallic compound $Mg_{17}$Al$_{12}$ during FSW causes the remarkable increase in hardness value in the stir zone.one.

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Effects of GBF Treatment Conditions and Scrap Ratio on the Electric Conductivity of Commercial Pure Aluminum (공업용 순알루미늄의 전기전도도에 미치는 스크랩비율 및 GBF처리조건의 영향)

  • Hwang, Nam-Gyu;Kim, Young-Chan;Choi, Se-Won;Kang, Chang-Seok;Hong, Sung-Kil
    • Journal of Korea Foundry Society
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    • v.31 no.3
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    • pp.130-136
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    • 2011
  • Effects of GBF (gas bubbling filtration) treatment conditions and scrap ratio on the electric conductivity of a commercial pure aluminum for diecasting were investigated using by specific gravity and electrical conductivity measurement system, hydrogen gas analyzer, XRD, and EDS. Electrical conductivities of specimen mixed Al scrap ratio until 60% from 0% were decreased with increasing the precipitates amount and size of AlFeSi ternary intermetallic compound on the grain boundary as well as amount of porosity in the grain. On the other hand, electrical conductivities was reincreased gradually in spite of scrap ratio increase from 80% to 100%. Size of AlFeSi compound formed on the grain boundary were coarsened with the increament of scrap ratios untill 80% and GBF treatment time simultaneously.

Corrosion Protection from Inhibitors and Inhibitor Combinations Delivered by Synthetic Ion Exchange Compound Pigments in Organic Coatings

  • Chrisanti, S.;Ralston, K.A.;Buchheit, R.G.
    • Corrosion Science and Technology
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    • v.7 no.4
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    • pp.212-218
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    • 2008
  • Inorganic ion exchange compounds (IECs) including hydrotalcites and bentonite clays are a well known classes of layered mixed metal hydroxides or silicates that demonstrate ion exchange properties. These compounds have a range of applications from water purification to catalyst supports. The use of synthetic versions of these compounds as environmentally friendly additives to paints for storage and release of inhibitors is a new and emerging application. In this paper, the general concept of storage and release of inhibiting ions from IEC-based particulate pigments added to organic coatings is presented. The unique aspects of the IEC structure and the ion exchange phenomenon that form the basis of the storage and release characteristic are illustrated in two examples comprising an anion exchanging hydrotalcite compound and a cation exchanging bentonite compound. Examples of the levels of corrosion protection imparted by use of these types of pigments in organic coatings applied to aluminum alloy substrates is shown. How corrosion inhibition translates to corrosion protection during accelerated exposure testing by organic coatings containing these compounds is also presented.