• Title, Summary, Keyword: BIS

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Synthesis of Novel Prepolymers Containing No Bisphenol A and Preparation of Organic Matrices for Dental Applications (비스페놀 A를 함유하지 않은 치과용 신규 프리폴리머의 합성 및 유기 매트릭스의 제조)

  • Son, Jun-Sik;Lee, Ki-Baek;Park, Kwi-Deok;Kim, Jae-Jin;Ahn, Kwang-Duk;Kim, Jung-Hyun;Han, Dong-Keun
    • Polymer Korea
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    • v.30 no.6
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    • pp.538-544
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    • 2006
  • Two kinds of novel bifunctional methacrylated prepolymers (170-2MA and 631-2MA) which have similar structure with 2,2-bis[4- (2'-hynroxy-3'-methacryloyloxypropoxy)phenyl] propane (Bis-GMA) was synthesized for dental applications as an alternative to Bis-GMA containing bisphenol A that is doubtful as an endocrine disrupter. The organic matrices were prepared by mixing a diluent and/or a monomer with the synthesized methacrylated prepolymers. The yield, viscosity, and chemical structures of the prepolymers and the physical and methanical properties of the organic matrices were evaluated. The yields of the prepolymers synthesized through a ring-opening reaction of epoxy compound and methacrylic acid were above 90% and the viscosities of the prepolymers were much lower than that of the Bis-GMA control. From the results of $^1H-NMR$ and FTIR analyses, the chemical structures of the prepolymers were similar to that of Bis-GMA. In addition, the curing time, poly-merization shrinkage, photoconversion, polymerization depth, and compressive strength of the organic matrices formulated with 170-2MA and 631-2MA prepolymers exhibited comparable to or better than those of the existing Bis-GMA-based one. These results suggest that the novel methacrylated prepolymers which have no endocrine disrupter can be an alternative to Bis-GMA and be applicable to dental polymer materials.

Solvent Extraction of Alkali Metal and Alkaline Earth Metal Cations Using a Mono-Crown Ether and Bis-(Crown Ether)s (Mono-Crown Ether와 Bis-(Crown Ether)s를 이용한 알칼리금속과 알칼리토금속 양이온들의 용매추출)

  • Shin, Young-Kook;Kim, Hae-Joong
    • Analytical Science and Technology
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    • v.10 no.1
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    • pp.60-65
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    • 1997
  • Solvent extraction of alkali metal and alkaline earth metal cations by mono-crown ether(benzo-15-crown-5) and bis-(crown ether)s(ethylenediamine bis(4'-formyl benzo-15-crown-5)) containing benzo-15-crown-5 moieties were investigated with water-chloroform system at $25^{\circ}C$. The order of the extraction equilibrium constants($K_e$) and the complexation constants($K_c$) for the alkali metal and alkaline earth metal cations with mono-crown ether and bis-(crown ether)s were Ca(II)>Na(I)>Sr(II)>K(I)>Mg(II)>Rb(I) and Sr(II)>Ca(II)>K(I)>Rb(I)>Mg(II)>Na(I) respectively. These results were explained in terms of the size effect of metal cation and electron density effect. Also, the bis-(crown ether)s was found to extract metal cations more effectively than the corresponding mono-crown ether.

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Cytotoxic Effects of Some Transition Metals, Nickel(II), Copper(II) and Zinc(II), with 3.6-bis(2'-pyridyl)pyridazines Complexes (몇 가지 전이금속, Ni(II), Cu(II) 및 Zn(II) 3,6-bis(2'-pyridyl)pyridazine 착 화합물들의 세포 독성효과)

  • Kwon, Byung-Mok;Lee, Chong-Ock;Choi, Sang-Un;Sung, Nack-Do
    • Applied Biological Chemistry
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    • v.49 no.1
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    • pp.21-24
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    • 2006
  • A series of cytotoxic activities $(ED_{50})$ in vitro against six human cancers (lung cancer, uterine cancer, skin cancer, brain cancer, colon cancer and adenocarcinoma) and their seventeen cell lines of 3,6-bis(2'-pyridyl)pyridazine, 1, 3,6-bis-(6'-methyl-2'-pyridyl)pyridazine, 2 and their transition metal, Ni(II), Cu(II) and Zn(II) complexes, $3{\sim}6$ were measured. Particularly, the results revealed that the cytotoxic activities against the brain cancer cell line (SNB-19) and the colon cancer cell line (SW62) of bis- [3,6-bis-(6'-methyl-2'-pyridyl)pyridazine-$k^2N^2,N^3$]chlorocopper(II)perchlorate, 4 were shown to be higher than that of the first generation anticancer agent, Cis-platin.

Reduction Effect of CO2 Emission on BIS Using Tier 3 Methodology - A Case Study on Daejun-Chungjoo Project - (Tier 3 방법론을 활용한 BIS 사업의 CO2 저감효과 분석 - 대전-청주 간 광역BIS 사업을 중심으로 -)

  • Chung, Younshik;Song, Taijin;Kim, Jeongwan
    • Journal of The Korean Society of Civil Engineers
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    • v.31 no.3D
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    • pp.375-381
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    • 2011
  • This study presents an analysis of $CO_2$ emission reduction effect on bus information system (BIS) which is operated to improve various services of bus transit such as rapid and on-time service. Although the Intergovernmental Panel on Climate Change (IPCC) released three methodological types of models for analyzing the amount of greenhouse gas reduction, this study used the Tier 3 method that is the most concrete one. A case study was performed to a 8.3 km section of Daejun-Chungjoo BIS system, and dataset required to the Tier 3 method was obtained from ITS-based surveillance systems. The study result showed that the reduction effect of $CO_2$ on BIS operation was yearly $39.45tCO_2/km$. Therefore, such effect can be potentially useful to a measurement of effectiveness (MOE) of BIS projects hereafter.

Binding Modes of New Bis-Ru(II) Complexes to DNA: Effect of the Length of the Linker

  • Kwon, Byung-Hyang;Choi, Byung-Hoon;Lee, Hyun-Mee;Jang, Yoon-Jung;Lee, Jae-Cheol;Kim, Seog-K.
    • Bulletin of the Korean Chemical Society
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    • v.31 no.6
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    • pp.1615-1620
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    • 2010
  • Bis-[dipyrido[3,2-$\alpha$:2',3'-c]phenazine)$_2$(1,10-phenanthroline)$_2Ru_2$]$^{2+}$ complexes (bis-Ru(II) complexes) tethered by linkers of various lengths were synthesized and their binding properties to DNA investigated by normal absorption and linear dichroism spectra, and fluorescence techniques in this study. Upon binding to DNA, the bis-Ru(II) complex with the longest linker (1,3-bis-(4-pyridyl)-propane), exhibited a negative $LD^r$ signal whose intensity was as large as that in the DNA absorption region, followed by a complicate $LD^r$ signal in the metal-to-ligand charge transfer region. The luminescence intensity of this bis-Ru(II) complex was enhanced. The observed $LD^r$ and luminescence results resembled that of the [Ru(1,10-phenanthroline)$_2$ dipyrido[3,2-$\alpha$:2',3'-c]phenazine]$^{2+}$ complex, whose dipyrido[3,2-$\alpha$:2',3'-c]phenazine (dppz) ligand has been known to intercalate between DNA bases. Hence, it is conclusive that both dppz ligands of the bis-Ru(II) complex intercalate. The binding stoichiometry, however, was a single intercalated dppz per ~ 2.3 bases, which violates the "nearest binding site exclusion" model for intercalation. The length between the two Ru(II) complexes may be barely long enough to accommodate one DNA base between the two dppz ligands, but not for two DNA bases. When the linker was shorter (4,4'-bipyridine or 1,2-bis-(4-pyridyl)-ethane), the magnitude of the LD in the dppz absorption region, as well as the luminescence intensity of both bis-Ru(II) complexes, was half that of the bis-Ru(II) complex bearing a long linker. This observation can be elucidated by a model whereby one of the dppz ligands intercalates while the other is exposed to the aqueous environment.

Comparison between cerebral state index and bispectral index during desflurane anesthesia

  • Cho, Sang-Hyeon;Kim, Sung-Su;Hyun, Dong-Min;Yoon, Hyeong-Suk;Han, Jung-Woo;Kim, Jin Sun
    • Korean Journal of Anesthesiology
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    • v.71 no.6
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    • pp.447-452
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    • 2018
  • Background: Cerebral state index (CSI) is an anesthesia depth monitor alternative to bispectral index (BIS). Published comparative studies have used propofol or sevoflurane. However, studies using desflurane have not been reported yet. Different volatile anesthetics have different electroencephalography signatures. The performance of CSI may be different in desflurane anesthesia. Therefore, the objective of this study was to compare CSI and BIS during desflurane anesthesia. Methods: Thirty-three patients were recruited. Desflurane and remifentanil were used to maintain general anesthesia. BIS and CSI were recorded simultaneously every minute. End-tidal concentration of desflurane was maintained at 4% from the beginning of surgery for 5 minutes. Pairwise data of CSI and BIS were obtained five times at one-minute intervals. This process was repeated in the order of 6%, 8%, and 10%. Results: BIS and CSI were negatively correlated with the end-tidal concentration of desflurane with a similar degree of correlation (correlation coefficient BIS: -0.847, CSI: -0.844). The relationship between CSI and BIS had a good linearity with a slope close to 1 ($R^2=0.905$, slope = 1.01). For the relationship between CSI and BIS at each end-tidal concentration of desflurane, CSI and BIS showed good linearity in 4% and 10% ($R^2=0.559$, 0.540). However, the linearity and slope were decreased in 6% and 8% ($R^2=0.163$, 0.014). Conclusions: CSI showed an equivalent degree of overall performance compared to BIS in desflurane anesthesia. Accounting for previous literature, CSI can be used as a good substitute for BIS regardless of the kind of anesthetics used.

Nickel Catalyzed Silylation Reaction of Carbonyl Compounds with 1,1'-Bis(dimethylsilyl)ferrocene (니켈 촉매를 이용한 1,1'-Bis(dimethylsilyl)ferrocene과 Carbonyl 화합물의 Silylation 반응)

  • Gong, Yeong-Geon;Lee, Jeong-Hyeon
    • Journal of the Korean Chemical Society
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    • v.46 no.2
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    • pp.139-144
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    • 2002
  • The nickel-catalyzed reation of 1,1'-bis(dimethysilyl)ferrocene[1] with carbonyls such as benzaldehyde, 4-cyaonbezaldehyde, trimethylacetaldehyde, acethon, and benzophenone afforded 3-oxa-2,5-disilacyclo-1,1'-ferrocene. In contrast, the reation of [1] with isobutyraldehyde under the same reation condition yielded the diinsertion products formed via the insertion of two aldehyde ligands into the Si-H bond of 1,1'-bis(dimethy)ferrocene.

Synthesis of New Bis-Crown Ether (Ⅱ) : Bis-Crown Ether with Siloxane Moiety (새로운 비스-크라운 에테르의 합성(제 2보) : 실옥산 사슬에 연결된 비스-크라운 에테르)

  • Chang, Seung Hyun;Kim, Jae Yong;Chung, Kwang Bo
    • Journal of the Korean Chemical Society
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    • v.40 no.9
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    • pp.635-639
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    • 1996
  • New bis-crown ether containing siloxane chain was synthesized. 1,3-Bis(trimethylsiloxy)-1,3-dimethyl-1,3-di(4'-ethylbenzo-18-crown-6) disiloxane (1) was synthesized by reaction of 4'-vinylbenzo-18-crown-6 with 1,3-bis(trimethylsiloxy)-1,3-dimethyl-1,3-disiloxane in the presence of Pt catalyst. 4'-Vinylbenzo-18-crown-6 was prepared through five-step reaction which started from the reaction of catechol and acetic anhydride.

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Preparation and Thermal Properties of Poly(enaminonitriles-ester)s Derived from Dicyanovinyl-Containing Bis-Hydroxy Monomers

  • 김종태;공명선
    • Bulletin of the Korean Chemical Society
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    • v.18 no.3
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    • pp.328-333
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    • 1997
  • Dicyanovinyl-containing bis-hydroxy monomers, p-bis[1-(4-hydroxypiperidinyl)]-2,2-dicyanovinyl]benzene (2), p-bis[1-[1-(2-hydroxyethyl)piperazinyl]-2,2-dicyanovinyl]benzene (3), p-bis[1-(4-hydroxyphenylamino)-2,2-dicyanovinyl]benzene (4) and p-bis[1-[N-methyl-(N-hydroxyethyl)amino]]-2,2-dicyanovinyl]benzene (5) were prepared from p-bis(1-chloro-2,2-dicyanovinyl)benzene (1) and the corresponding amino alcohol. The poly(enaminonitriles-ester)s with a variety of chemical structures in the main chain were prepared from them. The chemical structure of polymers was confirmed through the syntheses of their corresponding model compounds. The polymers are easily soluble in polar aprotic solvents such as DMF, DMSO and NMP. Brittle and hard films can be cast from DMF solutions of polymers. Most polymers showed a large exotherm in DSC analyses and undergo a curing reaction around 350 ℃ to form insoluble materials. The polymers consisting of rigid aromatic moieties show 80-88% residual weight at 500 ℃ under nitrogen.

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The Impact of BIS Regulation on Bank Behavior in Asset Management (신 BIS 자기자본규제가 은행자산운용행태에 미치는 영향)

  • Oh, Hyun-Tak;Choi, Seok-Gyu
    • The Korean Journal of Financial Management
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    • v.26 no.3
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    • pp.171-198
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    • 2009
  • The primary purpose of this study is to examine the impact of new BIS regulation, which is the preparations to incorporate not only credit risk but also market and operation risk, on the bank behaviors. As methodology, SUR(seemingly unrelated regression) and pool unit test are used in the empirical analysis of banks survived in Korea. It is employed that quarterly data of BIS capital ratio, ratio of standard and below loans to total loans, ratio of liquid assets to liquid liabilities, allowances for credit losses, real GDP, yields of corporate bonds(3years, AA) covering the period of 2000Q1~2009Q1. As a result, it could be indicated that effectiveness and promoting improvements of BIS capital regulation policy as follows; First, it is explicitly seen that weight of lending had decreased and specific gravity of international investment had increased until before BIS regulation is built up a step for revised agreement in late 2001. Second, after more strengthening of BIS standard in late 2002, banks had a tendency to decrease the adjustment of assets weighted risk through issuing of national loan that is comparatively low profitability. Also, it is implicitly sought that BIS regulation is a bit of a factor to bring about credit crunch and then has become a bit of a factor of economic stagnation. Third, as the BIS regulation became hard, it let have a effort to raise the soundness of a credit loan because of selecting good debtor based on its credit ratings. Fourth, it should be arranged that the market disciplines, the effective superintendence system and the sound environment to be able to raise enormous bank capital easily, against the credit stringency and reinforce the soundness of banks etc. in Korea capital market.

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