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Basic Relationships

In general, comprehensive studies have been made on heat transfer of different liquid metals (Hg, Na, NaK, PbBi, Li, etc.). Unless special measures are taken for liquid metal purification, heat transfer coefficients follow the relationship (for tubes)  [Pg.41]

Careful purification makes heat removal more intensive, as it is described in [6.12- [Pg.41]

Low heat transfer coefficient (6.4) is caused by thermal contact resistance at the wall-liquid boundary. Thermal resistance is influenced by surface wetting with coolant, oxide films formed on metal surface, as well as deposits of oxides and other impurities. Thermal contact resistance can hardly be evaluated, only possible upper limit can be specified [6.15, 6.16]  [Pg.41]

Dimensionless thermal contact resistance as Re function [6.15, 6.16] —PhBi other sympols Li, Na, NaK, Hg ------equation 6.6. [Pg.41]

Normal purification of liquid metal leads to almost complete elimination of thermal contact resistance due to depositions. [Pg.42]

Light has both wave-like and particle-like properties. As a wave, it is a combination of oscillating electric and magnetic fields perpendicular to each other and to the direction of propagation (Fig. 3.10). The distance between consecutive peaks is the wavelength, A, and the number of complete cycles passing a fixed point in 1 s is the frequency, v. They are inversely proportional through the relationship [Pg.52]

In the infrared region both microns [1 micron = 1 micrometer (/rm) = 10-6 m] and wavenumbers to (in cm ) are employed co is the reciprocal of the wave- [Pg.52]

FIGURE 3.10 The instantaneous electric (Ev) and magnetic (H. ) field strength vectors of a plane-polarized light wave as a function of position along the axis of propagation (jc) (from Calvert and Pitts, 1966). [Pg.52]

Since chemists often deal experimentally with moles rather than molecules, a convenient unit is a mole of quanta, defined as 1 einstein. The energy of 1 einstein of light of wavelength A in nm is [Pg.53]

Another unit used in photochemistry to express the energy of a quantum of radiation is the electron volt 1 eV = 96.49 kJ mol-1 = 23.06 kcal mol-1. Thus for A in nm [Pg.53]

Let us consider a simple, reversible electrode reaction occurring at an inert metal electrode, in accordance with the stoichiometric equation [Pg.4]

In electrode kinetics the rate of the reaction in Eq. (1) is usually evaluated in terms of the current density, j, which is affected by a number of physical variables, such as the electrical state of the interface (represented theoretically as the Galvani potential difference, A0), temperature, concentration of reacting species, and pressure, as well as by more complex variables hidden within such phrases as the nature of the electrode material and the nature of the solution  [Pg.4]

Assuming that the kinetics of the reaction in Eq. (1) is characterized in both directions by rate laws of first order with respect to the corresponding reacting species, then in accordance with transition-state theory, the rate law is written as follows  [Pg.5]

According to Guggenheim,the electrochemical Gibbs energy of activation can be conceptually represented by [Pg.5]

It is simplest to study the effect of temperature on the rate of the electrode reaction if all variables except temperature are held constant. Then, it follows from Eq. (2) that [Pg.6]


The basic relationship satisfied by the differential cross sections for the forward and reverse /transitions is... [Pg.2015]

This shows that Eqs. (1) and 2) are basically relationships between the Gibbs free energies of the reactions under consideration, and explains why such relationships have been termed linear free energy relationships (LEER). [Pg.182]

The explorative analysis of data sets by visual data mining applications takes place in a three-step process During the first step (overview), the user can obtain an overview of the data and maybe can identify some basic relationships between specific data points. In the second step (filtering), dynamic and interactive navigation, selection, and query tools will be used to reorganize and filter the data set. Each interaction by the user will lead to an immediate update of the data scene and will reveal the hidden patterns and relationships. Finally, the patterns or data points can be analyzed in detail with specific detail tools. [Pg.476]

Since the very beginning of chemistry, many efforts have been devoted to find out basic relationships between the characteristics of absorption spectra and the molecular structure of dyes. [Pg.68]

To understand the flow in turbomachines, an understanding of the basic relationships of pressure, temperature, and type of flow must be acquired. Ideal flow in turbomachines exists when there is no transfer of heat between the gas and its surroundings, and the entropy of the gas remains unchanged. This type of flow is characterized as a rever.sible adiabatic flow. To describe this flow, the total and static conditions of pressure, temperature, and the concept of an ideal gas must be understood. [Pg.113]

The expression in Equation 2.52 can be modified to Equation 2.75 to show the basic relationship for the exponent. [Pg.35]

Equation (3-159) is the basic relationship of this method. Several techniques have been developed for the estimation of AylAx. The simplest of these, known as Euler s method, is to evaluate Ay/Ax at jcq. From Eq. (3-156), this gives (A v/Ajc)o = kyoi which, used in Eq. (3-159), yields... [Pg.106]

This is the general expression for film growth under an electric field. The same basic relationship can be derived if the forward and reverse rate constants, k, are regarded as different, and the forward and reverse activation energies, AG are correspondingly different these parameters are equilibrium parameters, and are both incorporated into the constant A. The parameters A and B are constants for a particular oxide A has units of current density (Am" ) and B has units of reciprocal electric field (mV ). Equation 1.114 has two limiting approximations. [Pg.130]

Therefore, a different approach was followed in the present paper in order to improve the understanding of the relationship between the structure and the behavior of crosslinked polymers. A series of directly comparable model polymers were prepared with crosslink densities varying from high (thermoset) to zero (thermoplastic). Five polymers with well defined crosslink densities [11] were tested at various levels of deformation. This approach produced a small but assessable and fairly consistant body of results. Basic relationships derived from these results were related to corresponding results from the literature. [Pg.317]

In the form of treatment developed by Taft and his colleagues since 195660-62, the Hammett constants are analyzed into inductive and resonance parameters, and the sliding scale is then provided by multiple regression on these. Equations 5 and 6 show the basic relationships. [Pg.497]

Durand, R. Ptoc. of the Minnesota Internationa] Hydraulic Convention (1953) 89. Basic relationships of transportation of solids in pipes — experimental research. [Pg.228]

Rayleigh showed that for light scattering, the basic relationship is... [Pg.84]

A phase modulation can also be expressed as frequency modulation. The corresponding frequency deviation is the time derivative of the modulated phase angle (Pm t). According to the basic relationships Afrequency deviation Af(f) with respect to the carrier frequency fg, commonly known as the Doppler frequency shift... [Pg.31]

Figure 3. Basic Relationships for Insulating Surfaces 3 and no longer well defined. Ion Interactions with charged surface alters trajectories. Figure 3. Basic Relationships for Insulating Surfaces 3 and no longer well defined. Ion Interactions with charged surface alters trajectories.
The basic relationships between solubility and pH can be derived for any given equilibrium model. The model refers to a set of equilibrium equations and the associated equilibrium quotients. In a saturated solution, three additional equations need to be considered, along with the ionization Eqs. (2a)-(2d), which describe the equilibria between the dissolved acid, base or ampholyte in solutions containing a suspension of the (usually crystaUine) solid form of the compounds ... [Pg.68]

L.S. Ettre and J.V. Hinshaw, Basic Relationships of Gas Chromatography, Advanstar Communications, Eugene, OR (1993). [Pg.279]

The basic relationships between solubility and pH can be derived for any given equilibrium model. In this section simple monoprotic and diprotic molecules are considered [26,472-484,497]. [Pg.92]

The basic relationships of electrochemical kinetics are identical with those of chemical kinetics. Electrochemical kinetics involves an additional parameter, the electrode potential, on which the rate of the electrode reaction depends. The rate of the electrode process is proportional to the current density at the studied electrode. As it is assumed that electrode reactions are, in general, reversible, i.e. that both the anodic and the opposite cathodic processes occur simultaneously at a given electrode, the current density depends on the rate of the oxidation (anodic) process, ua, and of the reduction (cathodic) process, vc, according to the relationship... [Pg.264]

This is the basic relationship of electrode kinetics including the concentration overpotential. Equations (5.4.40) and (5.4.41) are valid for both steady-state and time-dependent currents. [Pg.301]

Dipleg Diameter. In the foregoing examples, the minimum 4" I.D. (see Fig. 19) was sufficiently large to pass the collected solids. The basic relationship for sizing diplegs takes the dimensionless form ... [Pg.812]

The main concept addressed in this new multi-part series is the idea of correlation. Correlation may be referred to as the apparent degree of relationship between variables. The term apparent is used because there is no true inference of cause-and-effect when two variables are highly correlated. One may assume that cause-and-effect exists, but this assumption cannot be validated using correlation alone as the test criteria. Correlation has often been referred to as a statistical parameter seeking to define how well a linear or other fitting function describes the relationship between variables however, two variables may be highly correlated under a specific set of test conditions, and not correlated under a different set of experimental conditions. In this case the correlation is conditional and so also is the cause-and-effect phenomenon. If two variables are always perfectly correlated under a variety of conditions, one may have a basis for cause-and-effect, and such a basic relationship permits a well-defined mathematical description. [Pg.381]

A brief review of the basic relationships between error types and power starts with considering each of five interacting factors (Gad, 1982a, 1999) that serve to determine power and define competing error rates. [Pg.114]

Aiming to construct explicit dynamic models, Eqs. (5) and (6) provide the basic relationships of all metabolic modeling. All current efforts to construct large-scale kinetic models are based on an specification of the elements of Eq (5), usually involving several rounds of iterative refinement For a schematic workflow, see again Fig. 4. In the following sections, we provide a brief summary of the properties of the stoichiometric matrix (Section III.B) and discuss the most common functional form of enzyme-kinetic rate equations (Section III.C). A selection of explicit kinetic models is provided in Table I. TABLE I Selected Examples of Explicit Kinetic Models of Metabolisin 1 ... [Pg.123]

The importance of comparing time-dependent and steady-state fluorescence measurements is well illustrated by the difficulty of resolving purely static from purely dynamic quenching. In either case, the basic relationship between the steady-state fluorescence intensity and quencher concentration is the same. The Stem-Volmer relationship for static quenching due to formation of an intermolecular complex is i... [Pg.18]


See other pages where Basic Relationships is mentioned: [Pg.424]    [Pg.257]    [Pg.15]    [Pg.17]    [Pg.21]    [Pg.25]    [Pg.27]    [Pg.31]    [Pg.33]    [Pg.35]    [Pg.45]    [Pg.1139]    [Pg.71]    [Pg.528]    [Pg.212]    [Pg.391]    [Pg.125]    [Pg.167]    [Pg.354]    [Pg.49]    [Pg.49]    [Pg.249]   


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