• 제목/요약/키워드: Complex Formation

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4 유기염기착화합물의 분석화학적연구 I. Chlorpromazine Bromthymol Blue Complex 의 분석화학적연구 (Studies on the Organic Base Complexes and their Application to Analytical Chemistry. I. A Study on the Formation of Chlorpromazine Bromothymol Blue Complex and its Application to Analytical Chemistry.)

  • 김차덕;심상혁;서정현
    • 약학회지
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    • 제9권1_2호
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    • pp.14-17
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    • 1965
  • It has been known that the organic base complexes formed with the anionic acid base indicators are highly soluble in non-polar solvents but relatively insoluble in water. In the work reported here the formation of the complex between chloropromazine and bromothymol blue was studied and applied it to the determination of the base. The values to determine the binding ratio of the base with the indicator at pH 3.5 obtained from the application of Job's method of continuous variation and mol ratio method were both 1:1. From the application of this reaction to the determination of the base with carbon tetrachloride as the solvent for the extraction, fairy good results have been obtained.

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3CaO.$Al_2O_3$의 수화반응에 미치는 글루콘산나트륨읨 영향(I) -흡착거동- (Ettect of Sodium Gluconate on the Hydration of 3CaO.$Al_2O_3$(I)-Adsorption Behavior-)

  • 김창은;이승헌;유종석;최진호
    • 한국세라믹학회지
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    • 제23권2호
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    • pp.38-42
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    • 1986
  • The adsorption behavior of 3CaO.$Al_2O_3$-sodium gluconate-$H_2O$ system by measuring adsorp-tion isotherm DTA and IR sepctra. The adsorbed amount of sodium gluconate on 3CaO.$Al_2O_3$ is exceedingly larger than 3CaO.$SiO_2$ and portland cement. From the DAT experiment the formation of complex is observed by the characteristic exothermic peak of the complex at 45$0^{\circ}C$ It is now strong deduced that the chemical bonding between gluconate anion and 3CaO.$Al_2O_3$ should be coordinative due to the complex formation on the surface 3CaO.$Al_2O_3$ from the IR spectra of sod-ium gluconate only and 3CaO.$Al_2O_3$ -sodium gluconate-$H_2O$.

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SNARE Assembly and Membrane Fusion: A Paramagnetic Electron Magnetic Resonance Study

  • Kweon, Dae-Hyuk
    • 한국생물물리학회:학술대회논문집
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    • 한국생물물리학회 2003년도 정기총회 및 학술발표회
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    • pp.32-32
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    • 2003
  • In the neuron, SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein receptors) assembly plays a central role in driving membrane fusion, a required process for neurotransmitter release. In the cytoplasm, vesicular SNARE VAMP2 (vesicle-associated membrane protein 2) engages with two plasma membrane SNAREs syntaxin 1A and SNAP-25 (synaptosome-associated protein of 25 kDa) to form the core complex that bridges two membranes. While various factors regulate SNARE assembly, the membrane also plays the regulatory role by trapping VAMP2 in the membrane. The fluorescence and EPR analyses revealed that the insertion of seven C-terminal core-forming residues into the membrane controls complex formation of the entire core region, even though preceding 54 core-forming residues are fully exposed and freely moving. When two interfacial Trp residues in this region were replaced with hydrophilic serine residues, the mutation supported rapid complex formation.

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Effects of Borane-Pyridine Complex on Mesophase Formation from Decant Oil

  • Han, Dong-Yun;Moon, Sook-Young;Lim, Yun-Soo
    • Carbon letters
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    • 제5권3호
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    • pp.113-117
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    • 2004
  • The mesophase pitch was prepared by adding 1~10 wt% of the borane-pyridine complex (BPC) to decant oil. It was prepared in a reactor held at $450^{\circ}C$ for 2 h in $N_2$ atmosphere. The mesophase pitches were analyzed using thermogravimetric analyzer (TGA), melting point apparatus, X-ray diffraction (XRD) and polarized optical microscope. The coke yield, softening point, toluene insoluble, density and content of anisotropy in the mesophase pitches were increased with BPC contents. The XRD profiles did not show any effect of addition of BPC on the formation of mesophase pitch, while the crystallinity of mesophase pitches was increased when the materials were heat treated with boron compound.

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Oxalate공침법에 의한 고온 초전도체 YBa2Cu3O7-$\delta$의 합성 II. Cu2+-Oxalate-Complex가 Y3+ 및 Ba2+의 용해도에 미치는 영향 (Synthesis of High Tc Superconductor YBa2Cu3O7-$\delta$ by Oxalate Coprecipitation Method II. The Effect of Cu2+-Oxalate-Complex Formation for the Solubilities of Y3+ and Ba2+)

  • 최진호;김배환;최규원
    • 한국세라믹학회지
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    • 제26권3호
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    • pp.395-401
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    • 1989
  • The concentrations of Cu(II), Y(III) and Ba(II) ionic species in aqueous solution due to the formation of Cu2+-oxalate-complex have been theoretically calculated with respect to pH and their solubility diagrams could be obtained. It was verified from the calculation that the excess of Cu2+ and Ba2+ should be added in order to obtain oxalate coprecipitates with the molar ratio of Y : Ba : Cu=1 : 2 : 3. The exact amount of excess species has been calculated with respect to the initial concentrations of metal ions and pH.

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Molecular Conformation-Dependent Complexation between Acidic- and Basic-Polypeptides via Hydrogen Bonding in Solution

  • 장천학;김현돈;조병기;이장우
    • Bulletin of the Korean Chemical Society
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    • 제16권1호
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    • pp.42-47
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    • 1995
  • Interpolymer complex formation between basic polypeptide poly(L-proline) Form Ⅱ (PLP(Ⅱ)) and acidic polypeptides poly(L-glutamic acid) (PLGA) and poly(L-aspartic acid)(PLAA) has been studied in water-methanol (1:2 v/v) mixed-solvent by viscometry, potentiometry, light scattering and circular dichroism (CD) measurements. It has been found that polymer complexes between PLP(Ⅱ) and PLGA (or PLAA) are formed via hydrogen bonding with a stoichiometric ratio of PLP(Ⅱ)/PLGA (or PLAA)=1:2 (in unit mole ratio) and that PLP(Ⅱ) forms polymer complex more favorably with PLGA than with PLAA. In addition, the minimum (for pH 5.0) and the maximum (for pH 3.2) in reduced viscosity of dilute PLP(Ⅱ)-PLGA mixed solutions are observed at 0.67 unit mole fraction of PLGA (i.e., [PLP(Ⅱ)]/[PLGA]=1/2). These findings could be explained in terms of molecular structure (or conformation) of the complementary polymers associated with the complex formation.

Photochemical Studies of Schiff Base Cu(II) Complex: (1) UV-Irradiation of N,$N^{\prime}$-bis(salicylidene)ethylenediamine copper(II)

  • 안병태
    • Bulletin of the Korean Chemical Society
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    • 제16권3호
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    • pp.202-204
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    • 1995
  • The ultraviolet photochemistry of N,N'-bis(salicylidene)ethylenediamine copper(II), Cu(sal)2en, was investigated with low pressure mercury lamp. Redution of Cu(Ⅱ) and formation of Cl- were shown on 254 nm irradiation both for aerated and deaerated chlorinated hydrocarbon solvent such as CH2Cl2, chloroform, and 1,2-dichloroethane. Relatively long lived $({\tau}=100{\mu}sec)$ intermediate was detected by flash photolysis. Overall photo-process can be described as the formation of Cl- and new copper complex, product(1) by chlorohydrocarbon mediation, photoinduced reduction by abstraction of halogen from solvent, followed by redox induced substitution of axial ligand with chlorine. Product(1) is possibly Cu(III) chlorosalicylaldeimido complex and cyclic -CH2CH2- moiety is absent in the structure. 247nm band of Cu(sal)2en should contain ligand to metal charge transfer character.

공단지역 주변 소나무림의 솔잎혹파리 형태적 특성 (Morphological Characteristics of Thecodiplosis japonensis (Diptera: Cecidomyiidae) Larvae in Pine Forests Around Onsan Industrial Complex in Ulsan, Korea)

  • 이총규
    • 한국응용곤충학회지
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    • 제56권1호
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    • pp.77-81
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    • 2017
  • 환경오염원으로부터 지역별 솔잎혹파리 피해도의 차이를 조사하기 위하여 실시한 결과, 솔잎혹파리 충영형성율은 석유화학공단에 의한 환경오염이 심각한 상황에 있는 공단지역은 충영형성률 47.94%이었고, 대조지역은 9.94%였다. 솔잎혹파리 피해엽은 공단지역 피해엽의 길이는 평균 4.5 cm 였으며, 대조지역은 평균 4.9 cm 이었다. 솔잎혹파리 피해엽의 충영내 유충의 수는 공단지역은 평균 3.4개체이었고, 대조지역은 2.4개체 이었다. 성숙유충의 크기는 공단지역이 유충체장은 2.40 mm, 체폭은 0.7 mm 이었으며, 대조지역의 유충체장은 2.45 mm, 체폭은 0.71 mm 이었다.

용매 고분자막 상에 고정된 나트륨 이온선택성 물질의 착물형성상수 결정 (Determination of Complex Formation Constant of Sodium-Selective Ionophores in Solvent Polymeric Membranes)

  • 강태영;김성배;오현준;한상현;차근식;남학현
    • 분석과학
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    • 제13권4호
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    • pp.466-473
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    • 2000
  • 용매고분자막 상에 칼륨과 다양한 나트륨이온 선택성 중성 운반체의 착물형성상수(${\beta}_{MLn}$)를 고분자막형 광센서(optode)와 이온선택성 전극(ISE)을 이용하여 결정하였다. 수소이온선택성 발색물질(chromoionophore : ETH 5294)에 가장 널리 쓰이는 나트륨 이온선택성 물질들(4-tert-butylcalix[4]arenetetraacetic acid tetraethyl ester, ETH 2120, bis[(12-crown-4)methyl] dodecyl-methylmalonate 및 monensin methyl ester)을 첨가한 막과 첨가하지 않은 막으로 두 가지 다른 조성의 PVC 막을 제작하여, 일정 pH(0.05 M Tris-HCl, pH7.2)에서 알칼리금속 양이온(나트륨과 칼륨)의 농도 변화에 따른 광학적 감응을 측정하고, 또 일정한 알칼리금속 양이온 농도(0.1M)에서 pH변화에 따른 광학적 감응을 측정하였다. 또한 유사한 조성의 막을 각각 재래식 전극체에 장착하고 일정한 알칼리금속 양이온의 농도(0.1M)에서 pH 변화에 따른 전위치를 측정하였다. 양이온/수소이온의 활동도 비($a_{M^+}/a_{H^+}$)와 상대흡광도로 도시한 광센서 감응곡선과 수소이온농도에 따른 전위차 감응곡선으로부터 나트륨 이온선택성 리간드들의 착물형성상수를 결정하였다. 목적이온과 방해이온에 대한 착물형성상수들의 비로부터 얻어진 값은 실험적으로 얻어진 이온선택성 전극의 선택계수와 근접함을 확인하였다.

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HIGH RESOLUTION OBSERVATIONS OF MOLECULAR GAS DISTRIBUTION IN GALAXIES

  • YUN MIN S.
    • 천문학회지
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    • 제29권spc1호
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    • pp.159-160
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    • 1996
  • Recent high resolution CO observations of normal and starburst galaxies at Owens Valley Millimeter Array are summarized. While normal disk galaxies generally show exponential distribution which follows the optical blue light, starburst galaxies are often characterized by a compact ($\~$1 kpc) nuclear complex whose surface gas mass density is strongly correlated with the observed large infrared luminosity and thus the ongoing massive star formation.

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