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Kinetic theory of stopping

The orbital implementation of the kinetic theory of stopping and its consequences 336... [Pg.335]

Since the formal settlement of the CAB approach was advanced by Sabin and Oddershede on firm theoretical grounds using the kinetic theory of stopping, its adequacy has been shown in reproducing with reasonable success the... [Pg.344]

THE ORBITAL IMPLEMENTATION OF THE KINETIC THEORY OE STOPPING AND ITS CONSEQUENCES... [Pg.336]

Using the orbital implementation of the kinetic theory together with the derived TFDW mean excitation energies obtained in the previous section, we have calculated the proton stopping as a function of projectile velocity for a selected number of elemental target materials in the gas phase (O, Ar, and Br) and in the condensed phase (Si, Ni, and Ga), as an example. Figures 7 and 8 show the results of this calculation (continuous curves) as compared with the predictions by OS [33] (solid circles) and with the corresponding empirical fit to experimental values... [Pg.354]

Jens Oddershede s ideas on stopping power theory and their impact and consequences have been briefly reviewed. We have centered our analysis on the relevance of the orbital implementation of the kinetic theory (KT) of stopping and the Bethe and Thomas-Reiche-Khun sum rules, since they have influenced profoundly the development of our research along these lines. [Pg.364]

The production of species i (number of moles per unit volume and time) is the velocity of reaction,. In the same sense, one understands the molar flux, jh of particles / per unit cross section and unit time. In a linear theory, the rate and the deviation from equilibrium are proportional to each other. The factors of proportionality are called reaction rate constants and transport coefficients respectively. They are state properties and thus depend only on the (local) thermodynamic state variables and not on their derivatives. They can be rationalized by crystal dynamics and atomic kinetics with the help of statistical theories. Irreversible thermodynamics is the theory of the rates of chemical processes in both spatially homogeneous systems (homogeneous reactions) and inhomogeneous systems (transport processes). If transport processes occur in multiphase systems, one is dealing with heterogeneous reactions. Heterogeneous systems stop reacting once one or more of the reactants are consumed and the systems became nonvariant. [Pg.3]

The results obtained in the case of primary halides were confirmed by kinetic studies of their reactions with stannylanions using a stopped flow technique. The resulting rate constants were much greater than those calculated for an electron transfer according to the Hush-Marcus theory which supports a nucleophilic reactivity rather than a single electron transfer pathway132. [Pg.695]

The very important irreversibility of all observable processes can be fitted into the picture in the following way. The period of time in which we live happens to be a period in which the //-function of the part of the world accessible to observation decreases. This coincidence is really not an accident, since the existence and the functioning of our organisms, as they are now, would not be possible in any other period. To try to explain this coincidence by any kind of probability considerations will, in my opinion, necessarily fail. The expectation that the irreversible behavior will not stop suddenly is in harmony with the mechanical foundations of the kinetic theory. [Pg.141]

Bond stopping cross sections for protons incident on molecular targets within the OLPA/FSGO implementation of the kinetic theory. ... [Pg.297]

The theory of physical kinetics relevant to FIA allows in its present form identification of the major parameters governing the sample zone dispersion, but its limitations are still serious. It does not describe exactly even the simplest one-line FIA system and is limited to description of a zone that moves at constant speed. Acceleration of the sample zone during injection, changes of flow velocity and dispersion patterns at confluence points, where additional streams are joining the main stream, or dispersion when the flow is stopped and accelerated, have to be investigated in greater detail (cf. Section 3.2). [Pg.122]

When the thermal conductivity attains the high-pressure asymptotic value, the mean free path of the gas molecules within the void spaces of the dried layer has become substantially less than the dimensions of the void spaces. During the transition in thermal conductivity from the low-pressure asymptote to the high-pressure asymptote, the mean free path of the gas molecules rivals the void space dimensions in magnitude, but once the mean free path is reduced to the point at which the gas phase within the solid matrix obeys simple kinetic theory, the thermal conductivity stops rising. [Pg.275]

Til. Hilczer, M., Brzykin, A.V., Tachiya, M. Theory of the stopped-flow method for studying micelle exchange kinetics. Langmuir 2001, 77(14), 4196-4201. [Pg.81]

Temperature must be held constant in equation (1.15), since changing the temperature changes the energy. The internal kinetic and potential energy of the molecules in a system is often referred to as the thermal energy. Kinetic-molecular theory predicts that motion will stop at the absolute zero of temperatures where the thermal energy will be zero. [Pg.17]

Of course, Marcus theory does not stop at this juncture but attempts to provide a quantitative relationship between reaction kinetics and thermodynamics. On the basis of Marcus theory the barrier to a particular reaction AG, may be described as a function of a parameter called the intrinsic barrier, AG, and the free energy of the reaction AG°. The particular relationship is presented in (112). The basic idea here is that the barrier height is composed of two contributions, a kinetic component termed the intrinsic... [Pg.184]


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See also in sourсe #XX -- [ Pg.98 , Pg.335 , Pg.336 , Pg.344 , Pg.364 ]




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