• 제목/요약/키워드: Kinetic Theory

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眞空 蒸着에 관한 速度論的 모델 (Kinetic Model on the Vacuum Deposition)

  • 김대수
    • 한국표면공학회지
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    • 제19권2호
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    • pp.51-58
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    • 1986
  • A theoretical model was proposed to predict the rate of particles impinging on the negatively biased substrate and the total kinetic energy per unit time. The model takes into an account of kinetic theory based on Maxwell statistics and elementary plasma theory, incorporated with Hertz-Knudsen's evaporation theory. It is found that as the bias potential increases the ion flux and kinetic energy increases to a value above which the effect of potential is insignificant.

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The Theoretical Calculations of Kinetic and Thermodynamics Parameters and Anharmonic Correction for the Related Reactions of NO3

  • Yu, Hongjing;Liu, Yancheng;Xia, Wenwen;Wang, Li;Jiang, Meiyi;Hu, Wenye;Yao, Li
    • 대한화학회지
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    • 제65권6호
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    • pp.419-432
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    • 2021
  • According to the transition state (TS) theory, Gaussian software and Yao and Lin (YL) method, the thermodynamics and kinetic data respectively were calculated, and anharmonic effect was considered for related reactions of NO3. The methods of calculating and fitting kinetic and thermodynamics parameters were provided by least square method and related equations in this paper. Notably, the fitted E of Arrhenius equation was close to the calculated barrier of related reaction by QCISD(T) method. Therefore, the kinetic fitting result can well express the physical meaning of E in Arrhenius equation. Besides, the conversion process and the reaction mechanism of NO3 were researched. For NO3, it seemed that its instability results from its easy reaction with other substances rather than the decompose reaction of itself.

포논 기체 운동론을 이용한 실리콘 내 포논 평균자유행로 스펙트럼 열전도율 기여도 예측 (Prediction of Spectral Phonon Mean Free Path Contribution to Thermal Conduction in Silicon Using Phonon Kinetic Theory)

  • 진재식
    • 대한기계학회논문집B
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    • 제41권5호
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    • pp.341-346
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    • 2017
  • 본 연구는 해석적 접근이 용이한 실리콘 내 포논 평균자유행로(mean free path, MFP) 스펙트럼(spectrum) 열전도 특성 예측 모델을 제시했다. 해석이 용이한 포논 기체 운동론(kinetic theory)을 적용하기 위해, 나노구조물의 현상학적 접근으로 열전도에 관여하는 포논 모드(mode)들만 추출하고, 300 K의 실리콘에 대한 포논의 분산관계(dispersion relations) 및 분극(polarization) 효과가 고려된 포논의 주파수 변화에 따른 비열(specific heat)과 군속도(group velocity) 및 MFP 정보를 사용했다. 300 K의 실리콘 내 포논의 MFP 스펙트럼 열전도율 기여를 계산하고, 기존 실험결과 및 제1원리 기법 결과와 비교하여, 본 방법의 타당함을 보였다. 본 연구를 통해, 나노구조물 열전달 해석모델 개발 및 나노재료 열전달 특성 조정(tailoring) 전략 설계에 필요한 포논 MFP 스펙트럼 열전도 특성 정보를 해석이 용이한 방법으로 구할 수 있는 방법을 제공했다.

Kinetic Energy Release in the Fragmentation of tert-Butylbenzene Molecular Ions. A Mass-analyzed Ion Kinetic Energy Spectrometric (MIKES) Study

  • Choe, Joong-Chul;Kim, Byung-Joo;Kim, Myung-Soo
    • Bulletin of the Korean Chemical Society
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    • 제10권2호
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    • pp.167-171
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    • 1989
  • Kinetic energy release in the fragmentation of tert-butylbenzene molecular ion was investigated using mass-analyzed ion kinetic energy spectrometry. Method to estimate kinetic energy release distribution (KERD) from experimental peak shape has been explained. Experimental KERD was in good agreement with the calculated result using phase space theory. Effect of dynamical constraint was found to be important.

Application of Monte Carlo Simulation to Intercalation Electrochemistry II. Kinetic Approach to Lithium Intercalation into LiMn2O4 Electrode

  • Kim, Sung-Woo;Pyun, Su-Il
    • 전기화학회지
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    • 제5권2호
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    • pp.86-92
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    • 2002
  • 속도론적 관점에서 키네틱 몬테 카를로 방법의 전기화학적 리튬 인터칼레이션에로의 응용에 대하여 다루었다. 우선 키네틱 몬테 카를로 방법과 전이상태이론의 기본 개념을 소개하였고, 확산거동을 평가하기 위한 시뮬레이션 과정을 설명하였다. 마지막으로 인터칼레이션 화합물중 $LiMn_2O_4$전극에 대해 전류 추이곡선과 선형 포텐셜 전류곡선을 해석하기 위해서 전이상태이론에 근거한 키네틱 몬테 카를로 방법을 셀-저항 제어조건하에서 사용하였다. 이로부터 키네틱 몬테 카를로 방법이 전기화학분야에서 리튬 인터칼레이션의 속도론적 연구에 매우 유용함을 알 수 있었다.

Eigenfunctions for Liouville Operators, Classical Collision Operators, and Collision Bracket Integrals in Kinetic Theory Made Amenable to Computer Simulations

  • Eu, Byung-Chan
    • Bulletin of the Korean Chemical Society
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    • 제33권3호
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    • pp.779-789
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    • 2012
  • In the kinetic theory of dense fluids the many-particle collision bracket integral is given in terms of a classical collision operator defined in the phase space. To find an algorithm to compute the collision bracket integrals, we revisit the eigenvalue problem of the Liouville operator and re-examine the method previously reported [Chem. Phys. 1977, 20, 93]. Then we apply the notion and concept of the eigenfunctions of the Liouville operator and knowledge acquired in the study of the eigenfunctions to cast collision bracket integrals into more convenient and suitable forms for numerical simulations. One of the alternative forms is given in the form of time correlation function. This form, on a further manipulation, assumes a form reminiscent of the Chapman- Enskog collision bracket integrals, but for dense gases and liquids as well as solids. In the dilute gas limit it would give rise precisely to the Chapman-Enskog collision bracket integrals for two-particle collision. The alternative forms obtained are more readily amenable to numerical simulation methods than the collision bracket integrals expressed in terms of a classical collision operator, which requires solution of classical Lippmann-Schwinger integral equations. This way, the aforementioned kinetic theory of dense fluids is made fully accessible by numerical computation/simulation methods, and the transport coefficients thereof are made computationally as accessible as those in the linear response theory.

핵의학 영상과 추적자 동력학 분석법을 이용한 생체기능 정량화 (Quantitation of In-Vivo Physiological Function using Nuclear Medicine Imaging and Tracer Kinetic Analysis Methods)

  • 김수진;김경민;이재성
    • Nuclear Medicine and Molecular Imaging
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    • 제42권2호
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    • pp.145-152
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    • 2008
  • Nuclear medicine imaging has an unique advantage of absolute quantitation of radioactivity concentration in body. Tracer kinetic analysis has been known as an useful investigation methods in quantitative study of in-vivo physiological function. The use of nuclear medicine imaging and kinetic analysis together can provide more useful and powerful intuition in understanding biochemical and molecular phenomena in body. There have been many development and improvement in kinetic analysis methodologies, but the conventional basic concept of kinetic analysis is still essential and required for further advanced study using new radiopharmaceuticals and hybrid molecular imaging techniques. In this paper, the basic theory of kinetic analysis and imaging techniques for suppressing noise were summarized.

용액중에서의 화학반응에 관한 동역학적 이론 (Kinetic Theory for Chemical Reactions in Liquids)

  • 신국조
    • 대한화학회지
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    • 제25권5호
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    • pp.291-299
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    • 1981
  • 용액중에서 화학반응을 설명하기 위하여 한개의 대표적인 입자의 반복적 충돌현상까지 고려한 동역학적인 이론을 경구모델을 사용하여 연구하였다. 반응성을 지닌 대표적인 입자의 상공간 밀도의 시간상관함수가 만족시키는 동역학방정식을 유도하였고 이로부터 비활성 용매 S중에서 일어나는 A + B ${\rightleftharpoons$ C + D 형태의 가역반응에 관계되는 반응속도 계수의 인자를 투영연산자방법으로 구하였다.

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