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Plank s equation

Dafa comparing the operation of fluidized beds wifh ofher types of freezing planf are also scarce. The models developed by Reynoso and Calvelo (1985), which are based on Plank s equation for fhe prediction of freezing fime, compare the production rate of peas in a fluidized bed freezer wifh that in a fixed bed confinuous freezer of fhe same dimensions. Af air velocities of 1.2 and 0.8 in fhe fluidized and... [Pg.86]

Fourier s equafion does nof fake into account convection, which in the case of food freezing governs heat transfer befween fhe food surface and fhe refrigerafing medium, for example cold air in the case of a fluidized bed. Second, and more importanfly, if cannof accounf for fhe removal of lafenf heaf and fhe resultant phase change. Of the models available to predict freezing time. Plank s equation (Plank, 1913, 1941) is one of fhe simplesf and most widely used and is derived in many standard texts (Singh and Heldman, 2001 Smith, 2003). The principal... [Pg.89]

Using Plank s equation, the frequency of that electromagnetic radiation, EMR, can be determined, radiation caused by the movement of matter. [Pg.60]

Plank s equation does not make provision for an original temperature, which may be above the freezing point. An approximate method to calculate the additional time necessary to cool from temperature Tq down to the freezing point 7 is as follows. Calculate by means of the unsteady-state charts the time for the average temperature in the material to reach Tf assuming that no freezing occurs using the physical properties of the unfrozen material. If there is no surface resistance. Fig. 5.3-13 can be used directly for... [Pg.364]

The specific pathways for energy transitions are shown in Figure 1 and can be derived by Plank s equation,... [Pg.519]

From the transition-state theory the reaction rate is represented by Equation 3, where Nj is Avogadro number and h is Plank s constant ... [Pg.24]

Nagaoka s equation (Nagaoka et al, 1955) is an extension of Plank s model and takes into account the time required to reduce the temperature from an initial temperature T, above the freezing poinf. The lafenf heat of fusion in equafion 3.3 is replaced by the total enthalpy change A/i which includes the sensible heat which must be removed in reducing the temperature from an initial T and in addition an empirical correction factor is included. Thus... [Pg.90]

In Equation (2.2), Ii and I2 are the like spins. yi is the gyromagnetic ratio of I nuclei, h is the Plank s constant and r denotes the length of the I1-I2 intemuclear vector. 6 is the angle between the static magnetic field and r. The B-term is called the flip-flop term and causes mutual spin-exchange when the energy levels of the states are very close to each other. Two dipolar precession frequencies in the rotating frame can be obtained from Equation... [Pg.24]

There are three official methods for the measurement of temperature, each with a specified range of use. Below the triple point of natural hydrogen (13.8033 K) the gas thermometer is the method of choice. From there to the melting point of silver at 961.78 °C, the electrical resistance of pure platinum is used for interpolation between fixed points. Above this temperature the measurements are based on Plank s radiation law. Thermocouples, however, are the devices most often used in practice. Tables and fitted equations have been extensively developed to relate the emf from the most common types of thermocouples to the ITS. Unfortunately, they have not been revised yet to accommodate the most recent change in the ITS. The interested reader is referred to the second edition of the monograph on temperature by Quinn. [Pg.155]

Equation 10.1. Energy is related to frequency and wavelength by Plank s constant, h, as in Equation 10.2. These relationships are sumaiized in Table 10.1. [Pg.300]

In this equation, D is the difference between the origin of energies and the minimum value of the curve. De is the residual energy, which is the vibration energy at absolute zero hV(/2, a-q is the inter-atom distance for the minimum energy, which is the equilibrium distance of the molecule. Constant a depends on the light speed c molecule reduced mass p. (p is related to the atomic masses by the equations in [10.5]) Plank s constant h and value x as defined by [10.5]. Constant a is written ... [Pg.225]

Figure 2 shows the results of the non-linear fitting procedure on a part of the equator, first and second layer lines of TMV. The diffraction pattern used was taken by Dr. S. Warren and Dr. G. Stubbs at the Max-Plank-Institut in Heidelberg, Germany. This pattern was taken on a Guinier camera and the arcsdue to disorientation are not circular. The natural coordinate system (3)of the camera (rather than polar coordi-nates)was used in the deconvolution procedure. The standard... [Pg.143]

Equation 4.7 is the Bohr postulate, that electrons can defy Maxwell s laws provided they occupy an orbit whose angular momentum (corresponding to an orbit of appropriate radius) satisfies Eq. 4.7. The Bohr postulate is not based on a whim, as most textbooks imply, but rather follows from (1) the Plank equation Eq. 4.3, AE = hv and (2) starting with an orbit of large radius such that the motion is essentially linear and classical physics applies, as no acceleration is involved, then extrapolating to small-radius orbits. The fading of quantum-mechanical equations into their classical analogues as macroscopic conditions are approached is called the correspondence principle [11]. [Pg.95]

Sitarski and Seinfeld (6) were the first to provide a theoretical basis for Fuch s semi-empirical formula, by solving the Fokker-Plank equation by means of Grad s (7) 13-moment method. Their solution was further improved by Mork et al. (8). The Brownian coagulation coefficient predicted by these models agrees fairly well with the Fuchs interpolation formula. However, the model does not predict the proper free molecular limit. The validity of the Fuchs semiempirical formula was further reinforced, by the Monte Carlo simulations of Brownian coagulation, by Nowakowski and Sitarski (9). [Pg.4]

As pointed out earlier, the Fokker-Plank equation [18] describes the motion of the fictitious particle only outside a sphere of radius 7 s + Xr. where RS(=2RV) is the radius of the sphere of influence. The motion of the fictitious particle in the region of thickness... [Pg.7]

Oh, Y.M., Lee, S. H., Park, S., Lee, J.S. (2004) A Numerical Study on Ultra-short Pulse Laser-induced Damage on Dielectrics Using the Fokker-Plank Equation, Int. J. Heat Mass Transfer, to appear. [Pg.302]

The state of the system is described by a probability distribution P (s, (p, t), which is a function of the walker position s and a functional of the field p. P s,(p,t) satisfies a Fokker-Plank equation that can be directly derived from (22) using standard techniques [57]. In [32] we show that, for large t, P s, functional space and centered around a function po (s ) that is the field corresponding to the free energy of the system F (s) ... [Pg.330]

A cornerstone of condensed phase reaction theory is the Kramers-Grote-Hynes theory. In a seminal paper Kramers solved the Fokker-Plank equation in two limiting cases, for high and low friction, by assuming Markovian dynamics y(t) S(t). He found that the rate is a non-monotonic function of the friction ( Kramers turnover .) Further progress was made by Grote and Hynes who... [Pg.70]

Nemst-Plank equation, drag coefficient, or Stefan-Maxwell erpiation Ohm s law... [Pg.544]


See other pages where Plank s equation is mentioned: [Pg.90]    [Pg.519]    [Pg.297]    [Pg.90]    [Pg.519]    [Pg.297]    [Pg.73]    [Pg.205]    [Pg.151]    [Pg.66]    [Pg.604]    [Pg.128]    [Pg.3]    [Pg.2]    [Pg.324]    [Pg.2]    [Pg.127]    [Pg.58]    [Pg.22]    [Pg.340]    [Pg.70]    [Pg.361]    [Pg.444]    [Pg.361]    [Pg.444]    [Pg.89]    [Pg.164]    [Pg.140]    [Pg.149]    [Pg.336]    [Pg.207]   
See also in sourсe #XX -- [ Pg.89 , Pg.90 , Pg.92 , Pg.100 ]




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