• Title/Summary/Keyword: association/dissociation

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Puritan Values as 'Force Behind' in Mourning Becomes Electra

  • Yang, Seung-Joo
    • English Language & Literature Teaching
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    • v.11 no.4
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    • pp.79-96
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    • 2005
  • Eugene O'Neill portrays Puritan values of the Mannon family inherited from their family past. Since Puritan values of the Mannons suppress the normal way of life and love, they retain only rigidity, without the charity which is the core element of the teaching of Christianity. With Puritan repression and its dissociation from the vital spring of life, the Puritan Mannons live in a world drained of life and in a world of hypocrisy between outer beauty and inner ugliness. Ironically, they think more of death itself, neglecting to feel the vitality of life. Working as a fate, Puritan values of the Mannon as 'Force Behind' in O'Neill's own term are the cause of suffering and destruction of the Mannons throughout the whole play. The mask-like house and faces are effectively used as a dramatic technique to express the distorted Puritan values.

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Kinetic Modeling of Non-Isothermal Anionic Styrene-Butadiene Block Copolymerization And Its Industrial Applications

  • Park, Seung-Young;Yeon, Young-Joo;Lee, Jong-Ku
    • Proceedings of the Polymer Society of Korea Conference
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    • 2006.10a
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    • pp.380-380
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    • 2006
  • Styrene-Butadiene diblock or styrene-butadiene-styrene triblock copolymers are industrially important materials for asphalt modification and adhesives. A kinetic modeling study on non-isothermal anionic styrene-butadiene diblock copolymerization system is presented. The model deals with the association/dissociation reaction of initiator and propagating ion pairs in its kinetic scheme. By comparing model calculation results with real plant data, it is possible to obtain useful ideas for more efficient plant operation. For example, the model clearly provides important relation between the reaction temperature profile and the conversion of monomers.

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Mechanism of Organogel Formation from Mixed-Ligand Silver (I) Carboxylates

  • Kim, Ji-Yeon;Park, Cheol-Hee;Kim, Sang-Ho;Yoon, Sung-Ho;Piao, Longhai
    • Bulletin of the Korean Chemical Society
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    • v.32 no.9
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    • pp.3267-3273
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    • 2011
  • Ag(I) carboxylate gelators with mixed-ligands were systemically investigated to understand the mechanism of the organic gel formation. The gelators constructed 3-D networks of nanometer-sized thin fibers which facilitated gel formation in various aromatic organic solvents, even at very low concentrations. The loss of reflection peaks in the X-ray diffraction data indicated the reduction of strong interactions between the long alkyl chains as the Ag(I) carboxylates formed gels by maximizing their interactions with the organic solvents. The gelation temperature ($T_{gel}$) was measured to explore the interaction between the gelator molecules and solvents depending on their composition and concentration. Based on the gelation phenomena, a dissociation/re-association mechanism was proposed.

Structure, Spectroscopic Properties and Reactions of Interstellar Molecule HC2N and Isomers :Ab initio Study

  • Park, Sung-Woo;Lee, Seong-Yul
    • Bulletin of the Korean Chemical Society
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    • v.23 no.11
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    • pp.1553-1559
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    • 2002
  • Calculations are presented for the molecule HC2N and its geometrical isomers. The structures, harmonic frequencies and dipole moments are reported. The potential energy surface of the [H,C,C,N] system is investigated in detail, and the transition states, intermediate complexes, and the energies of barrier for the isomerization and dissociation reactions are computed in order to determine the reaction paths and to estimate the stability of the isomers. The barriers of isomerization among HCCN, HCNC and HNCC are computed to be rather large and dissociations of these molecules are highly endothermic, indicating that these molecules are kinetically stable. The association reactions HC + CN→HCCN, HC + NC→HCNC, and HN + CC →HNCC are barrierless and very exothermic, suggesting that they may be considered as efficient means of producing the HCCN and the isomers in the laboratory and in interstellar space.

NO Removal Characteristics in $N_2$ for a Dielectric Barrier Discharge Reactor with the Variation of a Discharge Gap (유전체 장벽 방전 반응기에서 방전 간극의 변화에 따른 질소 분위기하의 NO 제거 특성)

  • 차민석;이재옥;신완호;송영훈;김석준
    • Proceedings of the Korea Air Pollution Research Association Conference
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    • 2000.11a
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    • pp.407-408
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    • 2000
  • 유전체 장벽 방전 반응기 (Dielectric Barrier Discharge (DBD) Reactor)를 이용한 비열 플라즈마(Non-thermal plasma) 공정에서 NO 제거 특성을 실험적으로 연구하였다. 질소 분위기에서 전자에 의한 NO 의 제거는 $N_2$ + e $\longrightarrow$ N + N + e 반응에 의한 질소의 전자충돌해리 (electron-impact dissociation)와 이 반응에 의하여 생성된 질소원자에 의한 NO 의 환원반응 N + NO $\longrightarrow$ $N_2$ + O 으로 설명될 수 있으며, 이로 인하여 $O_2$$H_2O$ 의 첨가에 따른 부산물(O, $O_3$, OH 등)에 의한 산화반응이 주로 일어나는 경우 (XO + NO $\longrightarrow$ X + NO$_2$) 와는 달리 NO 제거에 소모된 에너지를 평가하기에 용이한 장점이 있다(Penetrante et al., 1995). (중략)

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XPS STUDY ON DNA DAMAGE BY LOW-ENERGY ELECTRON IRRADIATION

  • Noh, Hyung-Ah;Cho, Hyuck
    • Journal of Radiation Protection and Research
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    • v.36 no.4
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    • pp.190-194
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    • 2011
  • After the first report that electrons with sub-ionization energy of DNA could cause single strand breaks or double strand breaks to DNA, there have been various studies to investigate the mechanisms of DNA damage by low-energy electrons. In this paper, we examined the possibility of using X-ray photoelectron spectroscopy (XPS) to analyze the dissociation patterns of the molecular bonds by electron irradiation on DNA thin films and tried to establish the method as a general tool for studying the radiation damage of biomolecules by low energ yelectrons. For the experiment, pBR322 plasmid DNA solution was formed into the films on tantalum plates by lyophilization and was irradiated by 5-eV electrons. Un-irradiated and irradiated DNA films were compared and analyzed using the XPS technique.

In Vivo Quantitative Analysis of PKA Subunit Interaction and cAMP Level by Dual Color Fluorescence Cross Correlation Spectroscopy

  • Park, Hyungju;Pack, Changi;Kinjo, Masataka;Kaang, Bong-Kiun
    • Molecules and Cells
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    • v.26 no.1
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    • pp.87-92
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    • 2008
  • We employed dual color Fluorescence Cross Correlation Spectroscopy (FCCS) to measure the interaction between PKA regulatory (RII) and catalytic subunits (CAT) in living cells. Elevation of intracellular cAMP with forskolin decreased the cross-correlation amplitude between RFP-fused RII (RII -mRFP) and GFP-fused CAT (CAT-EGFP) by 50%, indicating that cAMP elevation leads to dissociation of RII-CAT complexes. Moreover, diffusion coefficient analysis showed that the diffusion rate of CAT-EGFP was significantly increased, suggesting that the decreased RII-CAT association caused by cAMP generated free CAT subunits. Our study demonstrates that in vivo FCCS measurements and their quantitative analysis permit one not only to directly quantify protein-protein interactions but also to estimate changes in the intracellular cAMP concentration.

Drug Release from Ph-sensitive Interpenetrating Polymer Net-works Hydrogel Based on Poly(ethylene glycol) Macromer and Poly (acrylic acid)Prepared by UV Cured Method

  • Kim, In-Sook;Kim, Sung-Ho;Cho, Chong-Su
    • Archives of Pharmacal Research
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    • v.19 no.1
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    • pp.18-22
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    • 1996
  • Acrylate-terminated poly (ethylene glycol) (PEG) macromer was prepared by the reaction of PEG with acryloyl chloride. Photopolymerization of PEG macromer resulted in the formation of cross-linked PEG network. Interpenetrating polymer networks (IPNs) based on PEG and poly(acrylic acid) (PAA) was obtained via template polymerization of AA to the PEG network by UV curing. The swelling degree of the IPNs hydrogel increased with an increase of pH value due to the association-dissociation between carboxylic acid of PAA and either of PEG through hydrogen bounding. The swelling-deswelling behavior proceeded reversibly for the IPNs upon changing pH. Release of indomethacin from the IPNs demonstrated "on-off" regulation with pH fluctuation.

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A review on the NLP techniques for reducing anxiety in dental phobic patients (치과 공포증환자의 불안 경감을 위한 NLP기법에 대한 고찰)

  • Kwon, Won-Dal;Seol, Ki-Moon
    • The Journal of the Korean dental association
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    • v.48 no.11
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    • pp.829-840
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    • 2010
  • In recent years, medical techniques have provided patients with various measures to improve their quality of life. For dental treatment, drug-mediated sedation techniques for relieving dental anxiety have been developed, but behavior control through drugmediation may be limited because of possible side effects, contraindications, and the additional expense to the patient. Many patients tend to avoid the treatment or are unwilling to accept it and this makes both patients and dentists feel pressured. The field of NLP application might alleviate this uncomfortableness. Recently, NLP has spread to the dental and medical field rapidly and has been used in surgical treatments as well as in direct psychotherapy. NLP techniques which could be applied to dental phobic patients are as follows. 1) anchoring, 2) dissociation, 3) submodality change, 4) time line threapy, 5) swish pattern, 6) six step reframing, 7) parts integration, 8) modeling and imagination and so on. The aim of this study is to examine the strategy of NLP psychology so that dental phobic patients can be treated efficiently and effectively by the application of behavior management. Through NLP, patients can be induced to have more positive attitudes and experiences in future dental treatment.

Rat Liver $AT_1$ Receptor Binding Analysis for Drug Screening

  • Lee, Sunghou;Lee, Buyean;Hwasup Shin;Jaeyang Kong
    • Biomolecules & Therapeutics
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    • v.3 no.1
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    • pp.21-27
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    • 1995
  • The only compounds with antagonistic activity via AT$_1$receptor, one of two subtypes of angiotensin II (AII) receptor, have been demonstrated to block the vasoconstriction effects of AII and thereby provide therapeutic potential. This initiated the search for compounds with high specific affinity to AT$_1$receptor and their effective screening methods. The radioligand binding assay for the AII receptor is regarded as the primary method for the evaluation of AT$_1$receptor antagonists for their activity. In this paper, we characterized the liver AT$_1$receptor and describe the efficient method of the radioligand binding assay using rat liver as a source of AT$_1$receptor. Equilibrium binding studies with rat adrenal cortex, adrenal medulla, liver and bovine adrenal showed that the specific bindings of [$^3$H] AII were saturable in all tissues and the Scatchard plots of those data were linear, suggesting a single population of binding sites. Hill slopes were very near to the unity in all tissues. Kinetic studies of [$^3$H) AII binding in rat liver homogenates yielded two association rate constants, 4.10$\times$10$^{7}$ M$^{-1}$ min$^{-1}$ and 4.02$\times$10$^{9}$ M$^{-1}$ min$^{-1}$ , with a single dissociation rate constant, 7.07$\times$10$^{-3}$ min-$^{-1}$ , possibly due to the partial dissociation phenomenon. The rank order of inhibition potencies of [$^3$H] AII binding in rat liver was AII>Sarile>Losartan>PD 123177. Rat liver homogenates revealed to have very high density of homogeneous population of the AT$_1$receptor subtype, as the specifically bound [$^3$H] AII was not inhibited by PD 123177, the nonpeptide antagonist of AT$_2$. The results of this study demonstrated that the liver homogenates from rats could be the best receptor preparation for the AT$_1$receptor binding assay and provide an efficient system for the screening of newly synthesized candidate compounds of AT$_1$receptor antagonist.

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