• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.344-344
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• 2006

Poly(n-hexyl-(S)-3-methylpentylsilane) aggregates confined in microcapsules to keep the aggregation number and ranging in average polymer mass in a microcapsule from $2{\Box}10^{-16}\;to\;2{\Box}10^{-14}g$. were studied by circular dichroism measurements in ethanol (a non solvent) and tetrahydrofuran (an associative solvent at low temperature) at varioustemperatures. The size of each aggregate did not affect the optical activity because the circular dichroism was proportional to the aggregation number at the same condition. Moreover, the circular dichroism appreciably reflected the prepared method, i.e. temperature and solvent.

• Archives of Pharmacal Research
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• 제10권2호
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• pp.69-74
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• 1987

The characteristics of zipeprol-$\beta$-cyclodextrin system were studied by circular dichroism, competitive UV method and dialysis method. In this experiment, binding constants by competitive UV method, circular dichroism and dialysis method were 155 M$^{-1}$ 187 M$\^{-1}$/($\pm$ 5%) and 315 $^{-1}$, repectively. It shows that zipeprol forms 1:1 compelx with $\beta$-cyclodextrin by circular dichroism and 1:2 by dialysis method. pH profile shows that binding force seems to be a hydrophobic interaction. It is suggested that benzene ring be accomodated in the cavity of $\beta$-cyclodextrin.

• BMB Reports
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• 제28권6호
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• pp.546-551
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• 1995

The conformation studies of myelin P2 protein and two of its major peptides were carried out using circular dichroism and fluorescence spectroscopy in water and in lipid environments. Significant conformational changes occur when the protein or peptides were bound to gangliosides. Similar effects were also found in trifluoroethanol solutions. The conformational features of P2 protein and its major peptides were discussed in relation to the environmental changes and the disease-inducing effects.

• Bulletin of the Korean Chemical Society
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• 제6권4호
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• pp.238-240
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• 1985

Carbonato and diammine platinum(Ⅱ) complexes of resolved 6,6'-dimehtyl-2,2'-diaminobiphenyl have been prepared. The absolute configuration of the square planar platinum(Ⅱ) complexes is determined on the basis of stereospecificity of the 6,6'-dimethyl-2,2'-diaminobiphenyl ligand, circular dichroism spectra of the complexes, and nonempirical circular dichroism method.

• BMB Reports
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• 제35권3호
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• pp.343-347
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• 2002

The human protein tyrosine kinase-6 (PTK6) polypeptide that is deduced from the cDNA sequence contains a Src homology (SH) 3 domain, SH2 domain, and catalytic domain of tyrosine kinase. We initiated biochemical and NMR characterization of PTK6 SH3 domain in order to correlate the structural role of the PTK6 using circular dichroism and heteronuclear NMR techniques. The circular dichroism data suggested that the secondary structural elements of the SH3 domain are mainly composed of $\beta$-sheet conformations. It is most stable when the pH is neutral based on the pH titration data. In addition, a number of cross peaks at the low-field area of the proton chemical shift of the NMR spectra indicated that the PTK6 SH3 domain retains a unique and folded conformation at the neutral pH condition. For other pH conditions, the SH3 domain became unstable and aggregated during NMR measurements, indicating that the structural stability is very sensitive to pH environments. Both the NMR and circular dichroism data indicate that the PTK6 SH3 domain experiences a conformational instability, even in an aqueous solution.

• 한국자기학회지
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• 제20권5호
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• pp.201-205
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• 2010

X-선 자기 원형 이색성 측정은 자성물질을 구성하는 원소별 자기적 성질의 측정 및 궤도 자기 모멘트와 스핀 자기 모멘트를 구별하여 측정할 수 있다는 장점으로 인해 여러 가지 자성 신물질 및 다양한 기능성 자성 다층 박막의 연구에 많이 이용되어 왔다. 이 글에서는 이러한 X-선 자기 원형 이색성 현상의 원리 및 실험 방법 등을 설명하겠다. 또한 몇 가지 X-선 자기 원형 이색성을 이용한 최근 몇 가지 연구도 소개하려 한다.

• Current Applied Physics
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• 제18권11호
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• pp.1182-1184
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• 2018

The combination of angular spin momentum with electronics is a promising successor to charge-based electronics. The conduction bands in GaAs may become spin-polarized via optical spin pumping, doping with magnetic ions, or induction of a moment with an external magnetic field. We investigated the spin populations in GaAs with x-ray magnetic circular dichroism for each of these three cases. We find strong anti-symmetric lineshapes at the Ga $L_3$ edge indicating conduction band spin splitting, with differences in line width and amplitude depending on the source of spin polarization.

• Journal of Magnetics
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• 제13권3호
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• pp.85-87
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• 2008

I report a simple method to correct the saturation effect in absorption spectra measured in total electron yield (TEY) mode. It does not require additional measurements of the X-ray penetration depth. In order to check the reliability of the method, X-ray magnetic circular dichroism (XMCD) spectra for polycrystalline Fe were measured at two different incident angles, and then processed with the method. The two resultant XMCD spectra were identical, and their sum rule analysis produced the ratios of orbital magnetic moment to spin magnetic moment, which were very close to the well-known value.

• 공업화학
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• 제23권6호
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• pp.577-582
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• 2012

진동 원편광 이색성(VCD; Vibrational Circular Dichroism) 분석기기를 사용한 키랄 유도체의 광학순도 분석을 수행하였다. 이 분석법을 통하여 광학이성체의 절대배위와 2% 이내의 오차 범위 내에서 %EE 값을 용이하게 측정할 수 있었다. 또한 VCD분석을 연속순환방식으로 시간 변화와 함께 수행하여 키랄화합물의 %EE 값을 측정하였다. ECH와 글리시돌 두 키랄 성분이 섞인 2성분 계에서 특별한 분리조작 없이 각 성분에 대한 농도 및 %EE 변화를 동시에 모니터링하는 것이 가능하였다. 본 연구에서 응용한 VCD 분석법은 반응 중의 반응 속도 등을 연속적으로 측정하는데 유용한 기법이며, 서로 다른 키랄 화합물이 혼합되어 있는 경우에 각각의 광학순도를 시간 변화와 함께 비파괴법으로 측정하기에 편리한 방법임을 확인하였다.

• Journal of the Optical Society of Korea
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• 제18권4호
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• pp.365-369
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• 2014

We present accurate analytical solutions of the lineshapes of birefringence (rotation) and dichroism (absorption) spectroscopy for a circular anisotropic medium composed of atoms of the transition $J_g=0{\rightarrow}J_e=1$. The susceptibility of a weak probe beam was analytically calculated and was averaged over a Maxwell-Boltzmann velocity distribution. The lineshapes of the two spectroscopies were then presented in analytical forms at arbitrary values of the linewidths of the inhomogeneous (Doppler) broadening and the homogeneous (natural) broadening of the atoms.