• Title/Summary/Keyword: kinetic studies

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Kinetic Studies on the Nucleophilic Reactions of Substituted Benzylnitrates with Anilines in $CH_3CN-CH_3OH$ (아세토니트릴-메탄올 혼합용매계에서 질산벤질과 아닐린의 친핵성 치환반응)

  • Son, Chang Guk;Kim, Wang Gi;Lee, Su Jeong;Yang, Gi Yeol
    • Journal of the Korean Chemical Society
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    • v.34 no.3
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    • pp.227-231
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    • 1990
  • Kinetic studies on the nucleophilic reactions of p-substituted benzylnitrates with substituted anilines have been conductometically carried out in 50-100% $CH_3CN-CH_3OH$ mixtures. From the kinetic data, Hammett ${\rho}_C$ and ${\rho}_N$ values, Bronsted $\beta$ values, and solvatochromic coefficients were determined in order to examine the transition state variations caused by changes in substituents and solvent properties. It is concluded that the reaction proceeds via a synchronous $S_N2$ mechanism in which bond formation is more advanced than bond cleavage.

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Kinetic Studies of Reactions of Transition Metal Carbonyl Anion with Allyl Halides

  • Park, Yong-Kwang;Han, In-Sup;Huh, Tae-Sung;Marcetta York Darensbourg
    • Bulletin of the Korean Chemical Society
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    • v.10 no.2
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    • pp.134-137
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    • 1989
  • The reaction of $CpMo(CO)_3-M^+(M^+,\;Li^+,\;Na^+,\;K^+,\;PPN^{+a})$ with allyl halide was performed and the details of its counterion effects and solvent effect was investigated under the pseudo-first order conditions. The kinetic data from this reaction were compared with those from the reaction of the same anion with benzyl halides in terms of their inverse counterion effects.

Nucleophilic Substitution Reactions of 2-Chloro-2-Propen-1-yl Arenesulfonates with Anilines and N,N-Dimethylanilines in Acetonitrile

  • 오혁근;정은미;이익춘
    • Bulletin of the Korean Chemical Society
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    • v.19 no.12
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    • pp.1334-1336
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    • 1998
  • Kinetic studies are carried out on the reactions of 2-chloro-2-propen-1-yl arenesulfonates with anilines and N,N-dimethylanilines in acetonitrilile at 45.0 ℃. The 2-chloro substituent is found to deactive the allyl moiety with considerable decrease in the rates. The sign and magnitude of the cross-interaction constant (ρxz 0.3) and the inverse secondary kinetic isotope effect (kH/kD 0.92) support an SN2 mechanism with a relatively tight transition state. The possibility of an SN2' mechanism can be safely precluded based on the ρxz values observed.

Kinetics and Mechanism of the Reactions of S-Phenyl Dithiobenzoates with Benzylamines in Acetonitrile

  • 오혁근;신철호;이익춘
    • Bulletin of the Korean Chemical Society
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    • v.16 no.7
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    • pp.657-661
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    • 1995
  • Kinetic studies are carried out on the reaction of S-phenyl dithiobenzoates with benzylamines in acetonitrile at 30.0 ℃. Small magnitude of ρX (βX) as well as ρZ (βZ) obtained suggests rate-limiting nucleophilic attack of the thiocarbonyl carbon. This is supported by the unusually small magnitude of ρXY and ρYZ, albeit their signs do not agree with those expected. Moreover, the inverse secondary kinetic isotope effects (kH/kD<1.0) involving deuterated benzylamine nucleophiles are also in line with the proposed mechanism.

Kinetic Studies on Dimer $(CrMn(CO)_{10}\;^-)$ Disruptions

  • Yong Kwang Park;In Sup Han;Tae Sung Huh
    • Bulletin of the Korean Chemical Society
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    • v.11 no.3
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    • pp.221-224
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    • 1990
  • A kinetic study of the heterobimetallic dimer disruption of $PPN+^aCrMn(CO)_{10}$- by ligand L(L = CO, $PR_3$) is described. The rate was determined in several aprotic solvents. The results indicated that the reaction of $PPN+^aCrMn(CO)_{10}$- with $PR_3$ is of first order with respect to [$PPN+^aCrMn(CO)_{10}$-] and the heterolytic Cr-Mn bond dissociation energy is approximately 27 kcal/mol.

Kinetic Typography study on TV Entertainment Programs - Focused on <2 Days & 1 Night>, , - (TV 예능 프로그램의 키네틱 타이포그래피 연구 - <1박2일>, <런닝맨>, <무한도전>을 중심으로 -)

  • Kim, Hyun-Ki;Bang, Yoon-Kyeong
    • Cartoon and Animation Studies
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    • s.33
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    • pp.363-382
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    • 2013
  • Up until about ten years ago, the use of typography played only an auxiliary role on broadcast television programs, primarily by transmitting information in order to facilitate a basic understanding of content. Recently, however, kinetic typography has become an important component in broadcast production. In fact, kinetic typography has developed into a visual language and a means of artistic expression, one that is increasingly used in the production of entertainment programs on television. This paper analyzes six aspects of kinetic typography: manner of development, location, intent, expressive techniques, color and font selection. Particular attention is placed on their use in three highly rated television entertainment programs: "2 Days & 1 Night", "Running Man", and "Infinite Challenge". The development way consists of the technique : starts off with cut and ends with cut. While, other techniques show conversation and situation representation using Z axis : zoom-in, zoom-out in , X axis : pan in <2 Days & 1 Night>. and Y axis : tilt in . Typographic design elements, expression technique, color, font are shown up according to the feature of each program. The resulting analysis suggests new ways for motion arts designers and the broadcast media to use kinetic typography in the development of television programs.

Kinetics and Mechanism of Anilinolysis of Phenyl N-Phenyl Phosphoramidochloridate in Acetonitrile

  • Hoque, Md. Ehtesham Ul;Lee, Hai-Whang
    • Bulletin of the Korean Chemical Society
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    • v.33 no.10
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    • pp.3274-3278
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    • 2012
  • The kinetic studies on the reactions of phenyl N-phenyl phosphoramidochloridate (8) with substituted anilines ($XC_6H_4NH_2$) and deuterated anilines ($XC_6H_4ND_2$) have been carried out in acetonitrile at $60.0^{\circ}C$. The obtained deuterium kinetic isotope effects (DKIEs; $k_H/k_D$) are huge secondary inverse ($k_H/k_D$ = 0.52-0.69). A concerted mechanism is proposed with a backside attack transition state (TS) on the basis of the secondary inverse DKIEs and the variation trends of the $k_H/k_D$ values with X. The degree of bond formation in the TS is really extensive taking into account the very small values of the DKIEs. The steric effects of the two ligands on the rates are extensively discussed for the aminolyses of the chlorophosphate-type substrates on the basis of the Taft equation.

A Study on the Flow Characteristics in T-type Rectangular Duct (T-TYPE 사각덕트내의 유동특성 연구)

  • Lee, Haeng-Nam;Park, Gil-Moon;Lee, Duck-Gu
    • Proceedings of the KSME Conference
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    • 2001.06e
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    • pp.702-707
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    • 2001
  • The characteristics of flow in dividing regions are precise, therefore their classification is very important not only in industry but also in hydrodynamics. By now, many studies of flow in dividing regions have been performed, but flow characteristics that use visualization in dividing regions have not been studied. The present study of the PIV and the CFD exhibit average velocity distributions, kinetic energy distributions and total pressure distributions etc of the total flow field due to the development of the accurate visualization optical laser and of optical equipment. Also, PIV is accurate with the flows characteristics of the dividing region as continuous analysis is done using input equipment. The study analyzes average velocity vector field, average kinetic energy, x-axis stress distributions, average and total pressure distributions of dividing regions with flow for visualization of the PIV and the CFD measurement in a dividing rectangular duct.

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Effect of Partial Pressure of the Reactant Gas on the Kinetic Model and Mechanical Properties of the Chemical Vapor Deposited Silicon Carbide (화학증착된 실리콘 카바이드 박막의 속도론적 모델 및 기계적 성질에 미치는 반응가스 분압의 영향)

  • 어경훈;소명기
    • Journal of the Korean Ceramic Society
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    • v.28 no.6
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    • pp.429-436
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    • 1991
  • Silicon carbide has been grown by a chemical vapor deposition (CVD) technique using CH3SiCl3 and H2 gaseous mixture onto a graphite substrate. Based on the thermodynamic equilibrium studies and the suggestion that the deposition rate of SiC is controlled by surface reaction theoretical kinetic equation for CVD of silicon carbide has been proposed. The proposed theoretical kinetic equation for CVD of silicon carbide agreed well with the experimental results for the variation of the deposition rate as a function of the partial pressure of reactant gases. The Vikers microhardness of the SiC layer was about 3000∼3400 kg/$\textrm{mm}^2$ at room temperature.

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Kinetic modeling analysis for the decolorization of dyes using a mixed adsorbent

  • Ravikumar, K.;Son, Young-A
    • Textile Coloration and Finishing
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    • v.18 no.5 s.90
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    • pp.42-47
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    • 2006
  • A mixed adsorbent prepared by pyrolysing a mixture of carbon and flyash in 1:1 ratio was tested for its deceleration ability for three different classes of dyes namely, Astrazone Blue FRR(Basic Blue 69), Teflon flue ANL(Acid Blue 125) and Verofix Red(Reactive Red 3GL). Kinetic analyses were carried out at the optimum conditions obtained by the author in the previous studies. The data was fitted with three kinetic model equations. The results showed that the dye uptake mechanism followed the second-order rate expression.