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Cause of Surface voids in Concrete Attached to an Aluminum Form, and Measures for Prevention

  • Noh, Sang-Kyun;Lee, Seung-Hoon;Han, Cheon-Goo
    • Journal of the Korea Institute of Building Construction
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    • v.13 no.5
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    • pp.457-464
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    • 2013
  • Traditionally, the material used for the form in reinforced concrete construction has been wood or steel. But recently, aluminum forms have been widely used in wall structures such as apartment buildings. Aluminum is light, easy to handle, and economically advantageous, but the hydrogen gas created due to its reaction with the alkali component in concrete gives rise to air pockets on the concrete's surface, and deteriorates the surface's finishability. In this research, to determine the influence of aluminum material on concrete, the cement paste W/C and its chemical reactivity in alkali and acid solution were analyzed. As a prevention plan, the influence of the number of applications of calcium hydroxide and various surface coating materials was analyzed. Through the analysis, it was found that the surface voids on the aluminum form are the result of the reaction of hydrogen gas with an alkali such as $Ca(OH)_2$. This can be prevented by the surface treatment of $Ca(OH)_2$, separating material and coating material. However, poor surface form and damages to the form are expected to cause quality degradation because of the aluminum-concrete interaction. Therefore, thorough surface treatment, rather than the type of separating material or coating material, is considered the most important target of management.

Full-length Fas-associated Death Domain Protein Interacts with Short Form of Cellular FLICE Inhibitory Protein

  • Jeong, Mi-Suk;Jang, Se-Bok
    • Bulletin of the Korean Chemical Society
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    • v.27 no.1
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    • pp.87-92
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    • 2006
  • Fas-associated death domain protein (FADD) recruits and activates procaspase-8 through interactions between the death effector domains of these two proteins. Cellular FLICE-inhibitory protein (c-FLIP) was identified as a molecule with sequence homology to caspase-8. It has been postulated that c-FLIP prevents formation of the competent death-inducing signaling complex in a ligand-dependent manner, through its interaction with FADD and/or caspase-8. However, the interaction of FADD and $c-FLIP_s$ (short form) in apoptosis signaling has been controversially discussed. We show the purification and the characterization of human full-length FADD and $c-FLIP_s$ expressed in Escherichia coli. The purified FADD and $c-FLIP_s$ are shown as homogeneity, respectively, in SDS-PAGE analysis and light-scattering measurements. The folding properties of the $\alpha$-helical structure of FADD and the super-secondary structure of $c-FLIP_s$ proteins were characterized by circular dichroism spectroscopy. Furthermore, we report here a series of biochemical and biophysical data for FADD-$c-FLIP_s$ binding in vitro. The binding of both FADD and $c-FLIP_s$ proteins was detected by BIAcore biosensor, fluorescence measurement, and size-exclusion column (SEC).

Rates of Conformational Change of 3,3-Dimethylpiperidine and Solvent Effects on Its Conformation When Coordinated to the Paramagnetic Undecatungstocobalto(II)silicate Anion Studied by 1H NMR Spectroscopy

  • 현재원;소현수
    • Bulletin of the Korean Chemical Society
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    • v.18 no.9
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    • pp.961-965
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    • 1997
  • 1H NMR spectra of 3,3-dimethylpiperidine (1) at -70 to 30 ℃ exhibit gradual change from slow to rapid exchange between two alternate chair forms. The exchange rate constant was determined as a function of temperature by simulating the line shape of the signal from the two methyl groups using the modified Bloch equations. The resulting free energy of activation is ΔG* = 44.4±1.9 kJ mol-1 at 298 K. The 1H NMR spectrum of a D2O or dimethylsulfoxide-d6 (DMSO-d6) solution containing 1 and [SiW11CoⅡO39]6- exhibits separate signals for the free ligand and the complex, indicating that the ligand exchange is slow on the NMR time scale. In D2O the piperidine ring is frozen as a chair form even at room temperature with the cobalt ion bonded to the axial position of the nitrogen atom. When DMSO-d6 is added to the D2O solution, the NMR spectral change suggests that a rapid exchange occurs between the chair form and another conformer. It is proposed that the conformation of ^b1^b coordinated to [SiW11CoⅡO39]6- in DMSO-d6 is close to a twist form.

Syntheses and Reactions of Iridium Complexes Containing Mixed Phosphine-Olefin Ligand: (3-(Diphenylphosphino)propyl)(3-butenyl)phenylphosphine

  • Young-ae W. Park;Devon W. Meek
    • Bulletin of the Korean Chemical Society
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    • v.16 no.6
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    • pp.524-528
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    • 1995
  • The reaction of [IrCl(cod)]2 with ppol ligand, Ph2PCH2CH2CH2P(Ph)CH2CH2CH=CH2, in ethanol gives an iridium complex, whose structure is converted from an ionic form, [Ir(cod)(ppol)]Cl·2C2H5OH (1),in polar solvents (ethanol, methanol and acetonitrile), to a molecular form, [IrCl(cod)(ppol)], in non-polar solvents (benzene and toluene). The cationic complexes, [Ir(cod)(ppol)]AsF6·1/2C2H5OH and [Ir(cod)(ppol)]PF6·1/2CH3CN, were prepared to compare with the ionic form by 31P NMR spectroscopy. When carbon monoxide is introduced to 1, cod is replaced by CO to give the 5-coordinated complex, [IrCl(CO)(ppol)]. Hydrogenation of 1-octene was not successful in the presence of 1. In order to verify the reason for 1 not behaving as a good catalyst for hydrogenation, electrophilic reactions with HCl, I2 and HBF4·etherate were performed, which yielded the oxidative addition product, [IrHCl2(ppol)], the substitution product, [IrI(cod)(ppol)], and another cationic product, [Ir(cod)(ppol)]BF4, respectively. Thus, the iridium complex is not sufficiently basic to activate hydrogen atoms or the olefin of the ppol ligand.

A Study for Human-Error Prevention of Chemical Plant Safety Accident (Chemical 공장 안전사고의 Human-Error 방지에 대한 연구)

  • 윤용구;홍성만;박범
    • Journal of the Korea Safety Management & Science
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    • v.6 no.2
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    • pp.1-9
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    • 2004
  • The chemical factory deals with dangerous element and more advance, human-error analyzes and becomes effective research for the country and region. This paper analysis the form of work-miss on human-error according to a safety accident for domestic chemical factory from 1999-2002. It include the present contents and raise issues human knowledge, behavior, judgment, sensibility as an important counter plan that makes the safety solution of work miss. For the point of view of human knowledge, it takes color standard for works to be effective in work place. For behavior, the test has been for risk Point of work place and infra worker movement, also the workers performed professional work as classify according to work. For judgement, the valuation sheet is reflected to minimize the human-error and the 3rd supervisor does a cross-check audit beforehand. For sensibility, it is applicable for human relations, information, communication by program to the consciousness and an attitude of worker-supervisor.

Anticancer and Antiviral Effect of Some Triterpenes Isolated from the Natural Sources

  • Kim, Young-Sup;Choi, Sang-Un;Lee, Chong-Ock;Lee, Chong-Kyo;Ryu, Shi-Yong
    • Proceedings of the PSK Conference
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    • 2002.10a
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    • pp.138-139
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    • 2002
  • The diverse, widespread, and exceedingly numerous family of natural products constructed from five carbon building-units and so comprising compounds with $C_{5}$, $C_{10}$, $C_{15}$, $C_{20}$, ${\cdots}$, $C_{40}$ skeletons (together with a few higher members) are synoymously termed terpenes or terpenoids. Among the terpene classes, the triterpenes ($C_{30}$ skeletones) form the largest group and are widely distributed in the plant kingdom, either in the free state or as esters or glycosides, although a few important members found in the animal kingdom such as squalene and a number of tetracyclic component including lanosterol. (omitted)

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A Study for Human-Error Prevention of Chemical Plant Safety Accident (Chemical 공장 안전사고에 Human-Error 방지에 대한 연구)

  • 윤용구;홍성만;박범
    • Proceedings of the Safety Management and Science Conference
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    • 2004.05a
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    • pp.33-39
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    • 2004
  • The chemical factory deals with dangerous element and more advance, human-error analyzes and becomes effective research for the country and region, this paper analyes the form of work-miss on human-error according to a safety accident for domestic chemical factory from 1999-2002. It include the present contents and raise issues human knowledge, behavior, judgment, sensibility as an important counterplan that makes the safety solution of work miss. For the point of view of human knowledge, it takes color standard for works to be effective in work place. for behavior, the test has been for risk point of work place and infra worker movement, also the workers performed professional work as classify according to work. for judgement, the valuation sheet is reflected to minimize the human -error and the 3rd supervisor does a cross-check audit beforehand. For sensibility, it is applicable for human relations, information, communication by program to the consciousness and an attitude of worker-supervisor.

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Studies on Corrosion Inhibitors (Inhibitor에 關한 硏究)

  • Kae Soo Lee
    • Journal of the Korean Chemical Society
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    • v.13 no.1
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    • pp.13-15
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    • 1969
  • This investigation is to make comparative evaluation of the corrosion inhibiting effects of quinoline, oxine and 7-nitroso 8-hydroxy quinoline (7NHQ). In case of quinoline, and oxine, since the N atom in them functions as cation, the process involved is assumed to be cathode control. On the other hand 7-NHQ was found to form a stable chelate compound with $Fe^{++}$ ion in acidic solution and shows as anode control predominantly. After plotting polarization curves, Tafel parameters were calculated in each solution involving the inhibitors, at the same time corrosion inhibiting effects were separately measured and compared from data of both corrosion current and analytical method.

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Application of Biofilter Using Fibril-form Matrix for Odor Gas Removal

  • Lee, Gwang-Yeon;Jeong, Gwi-Taek;Lee, Kyoung-Min;Snuwoo, Chang-Shin;Lee, Woo-Tae;Cha, Jin-Myoung;Jang, Young-Seon;Park, Don-Hee
    • 한국생물공학회:학술대회논문집
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    • 2005.04a
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    • pp.247-251
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    • 2005
  • This research was performed for developing of biological treatment process of odor gas such as MEK, $H_{2}S$, and toluene, which is generated from the food waste recycling process. To establish the operational conditions of odor gas removal by small-scale biofiltration equipment, it was continuously operated by using toluene as a treating odor object. When the odor treating microorganisms were adhered to fibril form biofilter, high removal efficiency over 93% was obtained by biofilm formation. At 400 ppm of inlet odor gas concentration and 10 sec of retention time, the removal efficiency was 76% and 93% in 1st stage reactor and 2nd stage reactor, respectively. However, the removal efficiency remained over 97% at the operational conditions above 15 sec of retention time.

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Structure and Chemical Reactivity of the Transition Metal Complexes (I). Synthesis and Geometrical Isomerism of the Ethylenediamine-triacetatocobalt (III) Complexes with Ammine or Diamines (전이금속착물의 구조와 그 반응성 (I). 암민류를 포함하는 Ethylenediamine-triacetatocobalt (III) 착물의 합성과 기하이성질현상)

  • Dong-Jin Lee;Bong-Gon Kim;Myung-Ki Doh
    • Journal of the Korean Chemical Society
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    • v.29 no.5
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    • pp.516-521
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    • 1985
  • Ethylenediamine-triacetatocobalt (III) complexes with an ammine, an ethylene-diamine, and a trimethylenediamine as the unidentate ligand were prepared, and were isolated as only one isomer for each case by the Dowex 50W-X8, cation exchange resin in $H^+$ form. The geometrical isomer of these complexes have been assigned cis-equatorial form in the three possible geometrical isomers from the elemental analysis, pH titration, IR, NMR, and electronic absorption spectrum. It was found that $[CoN_3O_3]$ system of the meridional form with multidentate ligand have the first absorption band of the largely splitting pattern, and that the diamines (ethylenediamine, trimethylenediamine) have coordinated to the central cobalt (III) ion as a unidentate ligand.

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