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Fundamental equation applicability

The binomial distribution function is one of the most fundamental equations in statistics and finds several applications in this volume. To be sure that we appreciate its significance, we make the following observations about the plausibility of Eq. (1.21) ... [Pg.44]

We attempt here to describe the fundamental equations of fluid mechanics and heat transfer. The main emphasis, however, is on understanding the physical principles and on application of the theory to realistic problems. The state of the art in high-heat flux management schemes, pressure and temperature measurement, pressure drop and heat transfer in single-phase and two-phase micro-channels, design and fabrication of micro-channel heat sinks are discussed. [Pg.7]

Gibbs found the solution of the fundamental Equation 9.1 only for the case of moderate surfaces, for which application of the classic capillary laws was not a problem. But, the importance of the world of nanoscale objects was not as pronounced during that period as now. The problem of surface curvature has become very important for the theory of capillary phenomena after Gibbs. R.C. Tolman, F.P. Buff, J.G. Kirkwood, S. Kondo, A.I. Rusanov, RA. Kralchevski, A.W. Neimann, and many other outstanding researchers devoted their work to this field. This problem is directly related to the development of the general theory of condensed state and molecular interactions in the systems of numerous particles. The methods of statistical mechanics, thermodynamics, and other approaches of modem molecular physics were applied [11,22,23],... [Pg.266]

Another important field of the application of fractal approach to texturology is related to surface roughness. Anvir and Pfeifer [212,213] proposed characterization of surface irregularities by adsorption and established two methods, based on Mandelbrot s fundamental equations of type 9.69. According to the first method of Dt calculation, one uses the relations that interrelate a number of molecules in a complete monolayer during physisorption, nm, or an accessible surface area, A, with a cross-sectional area, w, which correspond to one molecule in a monolayer ... [Pg.317]

The direct access to the electrical-energetic properties of an ion-in-solution which polarography and related electro-analytical techniques seem to offer, has invited many attempts to interpret the results in terms of fundamental energetic quantities, such as ionization potentials and solvation enthalpies. An early and seminal analysis by Case etal., [16] was followed up by an extension of the theory to various aromatic cations by Kothe et al. [17]. They attempted the absolute calculation of the solvation enthalpies of cations, molecules, and anions of the triphenylmethyl series, and our Equations (4) and (6) are derived by implicit arguments closely related to theirs, but we have preferred not to follow their attempts at absolute calculations. Such calculations are inevitably beset by a lack of data (in this instance especially the ionization energies of the radicals) and by the need for approximations of various kinds. For example, Kothe et al., attempted to calculate the electrical contribution to the solvation enthalpy by Born s equation, applicable to an isolated spherical ion, uninhibited by the fact that they then combined it with half-wave potentials obtained for planar ions at high ionic strength. [Pg.224]

The third technique uses the fundamental equations, and converts them into dimensionless equations with length and velocity scales important to the application. From these dimensionless equations, dimensionless numbers will evolve. It is this technique that will be described herein. [Pg.87]

From a thermodynamic point of view the most important reaction characteristic for practical application is its free enthaply change AG°. According to the fundamental equation AG°=-RTlnK, the equilibrium constant of the reaction is determined by AG°. A high negative value (-20 kJ/mol or even less) usually imphes that the reaction results in high yield and quantitative transformation of substrate to product... [Pg.314]

This fundamental equation explains that the velocity of heavier ions (iq of ions with mass m,) is lower than of lighter ions (v2 of ions with mass m2, with m, > m2). Equation (10) is used directly in time resolved measurements, for example in time-of-flight mass spectrometers (ToF-MS). The charged ions of the extracted and accelerated ion beam are separated by their mass-to-charge ratio, m/z, in the mass analyzer. Mass-separated ion beams are subsequently recorded by an ion detection system either as a function of time or simultaneously. Mass spectrometers are utilized for the determination of absolute masses of isotopes, atomic weights, relative abundance of isotopes and for quite different applications in survey, trace, ultratrace and surface analysis as discussed in Chapters 8 and 9. [Pg.4]

In order to describe microscopic systems, then, a different mechanics was required. One promising candidate was wave mechanics, since standing waves are also a quantized phenomenon. Interestingly, as first proposed by de Broglie, matter can indeed be shown to have wavelike properties. However, it also has particle-Uke properties, and to properly account for this dichotomy a new mechanics, quanmm mechanics, was developed. This chapter provides an overview of the fundamental features of quantum mechanics, and describes in a formal way the fundamental equations that are used in the construction of computational models. In some sense, this chapter is historical. However, in order to appreciate the differences between modem computational models, and the range over which they may be expected to be applicable, it is important to understand the foundation on which all of them are built. Following this exposition. Chapter 5 overviews the approximations inherent... [Pg.105]

In addition, several alternative formulations of thermodynamic geometry have been presented, starting from entropy-based (or other) fundamental equations (see Sections 5.4 and 5.5). From the equilibrium thermodynamics viewpoint, these alternative formulations are completely equivalent, and each could be considered a special case of the general transformations outlined in Section 11.4. Nevertheless, each alternative may suggest distinct statistical-mechanical origins, Riemannian paths, or other connotations that make it preferable for applications outside the equilibrium thermodynamics framework. [Pg.423]

This equation is the fundamental equation for the energy function, and one such equation is applicable to each homogenous region. [Pg.378]

Applicable to investigation of equilibrium properties Random alterations of dispersion states, which are accepted or rejected based on a probability function that depends on the free energy change Applicable to systems with simple geometry Generates particle trajectories based on fundamental equations of motion (e.g. Newton s equation)... [Pg.540]

This relation can be obtained from the fundamental equation (Chap. I (4)) for the form of a liquid surface under gravity and surface tension. Unfortunately this equation cannot be solved in finite terms. Approximate solutions have been obtained in several ways which are outside the scope of this book. Sufficient account must, however, be given of the methods of Bashforth and Adams,1 to enable the reader to use their tables of numerical results, which are the most complete and accurate ever compiled. Some other important approximate formulae will also be given, for applications of the fundamental equation to special cases. [Pg.365]

The fundamental equations generally applicable to flow processes are presented in Sec. 7.1, and in later sections these equations are applied to specific1 processes. [Pg.115]

Calculation of equilibrium conversions is based on the fundamental equations of chemical-reaction equilibrium, which in application require data for the standard Gibbs energy of reaction. The basic equations are developed in Secs. 15.1 through 15.4. These provide the relationship between the standard Gibbs energy change of reaction and the equilibrium constant. Evaluation of the equilibrium constant from thermodynamic data is considered in Sec. 15.5. Application of this information to the calculation of equilibrium conversions for single reactions is taken up in Sec. 15.7. In Sec. 15.8, the phase role is reconsidered finally, multireaction equilibrium is treated in Sec. I5.9.t... [Pg.262]

In Chap. 6 we treated the thermodynamic properties of constant-composition fluids. However, many applications of chemical-engineering thermodynamics are to systems wherein multicomponent mixtures of gases or liquids undergo composition changes as the result of mixing or separation processes, the transfer of species from one phase to another, or chemical reaction. The properties of such systems depend on composition as well as on temperature and pressure. Our first task in this chapter is therefore to develop a fundamental property relation for homogeneous fluid mixtures of variable composition. We then derive equations applicable to mixtures of ideal gases and ideal solutions. Finally, we treat in detail a particularly simple description of multicomponent vapor/liquid equilibrium known as Raoult s law. [Pg.448]

Based on W. Heepke s model, ibid., the fundamental equation of the oven of Gusen that expresses the average consumption of a cremation is ——-— r +———= 30.6, with L = heat difference of combustion gases between entry and exit + small losses W2 = vaporization heat of water of the corpse W2a = heat required to bring water steam up to the temperature of the exiting combustion gases W3 = heat of the ashes at the extraction from the oven Vis = loss of heat of the oven by radiation and conduction W7 = calorific value of the body (and coffin, if applicable) i]I lu = efficiency of coke. [Pg.391]

In the chemical applications of this model the problem and its solutions are imbedded into a suitable FIEM. For instance, in bilateral synthesis design the EMb(A) of the starting materials and the target EMe(A), i.e. the target molecule and its coproducts, correspond to the fee-points P(B) and P(E), and the pathways that connect P(B) with P(E) via the fee-points of intermediate EMs are the conceivable syntheses. The solutions of such chemical problems are found by solving the fundamental equation... [Pg.206]

Fundamentals of spectrophotometer readings In order to best understand the use of UV/visible spectrophotometry and a spectrophotometer instrument it is important to first understand the data that can be derived from the use of this technique/equipment. The fundamental outcome from the use of a spectrophotometer is a measure of transmittance or absorbance. As the names suggest, transmittance (T) is the amount of light that is transmitted through the sample solution whereas absorbance (A) is a measure of light absorbed by the sample solution. Modern instmments can provide readings of both transmittance and absorbance (or its reciprocal 1/A) normally the primary reading for most bio-analytical applications is absorbance. However, it is important to appreciate that transmittance and absorbance are related by fundamental equations. [Pg.107]

Not only the internal pressure of a solvent can affect chemical reactions (see Section 5.4.2 [231, 232]), but also the application of external pressure can exert large effects on reaction rates and equilibrium constants [239, 429-433, 747-750]. According to Le Chatelier s principle of least restraint, the rate of a reaction should be increased by an increase in external pressure if the volume of the activated complex is less than the sum of the volumes of the reactant molecules, whereas the rate of reaction should be decreased by an increase in external pressure if the reverse is true. The fundamental equation for the effect of external pressure on a reaction rate constant k was deduced by Evans and Polanyi on the basis of transition-state theory [434] ... [Pg.308]

V. Weak Base and Strong Acid.—The equations applicable to the neutralization of weak bases are similar to those for weak acids the only alterations necessary are that the terms for II " and OH are exchanged, a and h are interchanged, and kb replaces ka. The appropriate form of equation (39), which is fundamental to the whole subject, is... [Pg.394]

There is nothing in the foregoing discussion that restricts it to reactions at the cathode or to ions it holds, in fact, for any electrode process, either anodic, i.e., oxidation, or cathodic, i.e., reduction, using the terms oxidation and reduction in their most general sense, in which the concentration of the reactant is decreased by the electrode process, provided the potential-determining equilibrium is attained rapidly. The fundamental equation (10) is applicable, for example, to cases of reversible oxidation of ions, e.g., ferrous to ferric, ferrocyanide to ferricyanide, iodide to iodine, as well as to their reduction, and also to the oxidation and reduction of non-ionized substances, such as hydroquinone and qui-none, respectively, that give definite oxidation-reduction potentials. [Pg.450]

In order to make the fundamental equation (i) generally applicable, it would be necessary relation... [Pg.37]

In the more recent development of these laws the active mass occurs again, as the concentration but the deduction of the fundamental equation is different, and allows of its application only to the case of extreme dilution. [Pg.104]

The first conclusion to be drawn from the application of the fundamental equation is that when only one substance is present as gas or vapour, which is absent in the solid form, its concentration must be constant at any given temperature, i. e. its pressure must be. The phenomenon thus, by the existence of a maximum pressure, connects with that of simple evaporation e. g. there is a maximum pressure for the partial decomposition of calcium carbonate ... [Pg.149]


See other pages where Fundamental equation applicability is mentioned: [Pg.359]    [Pg.490]    [Pg.312]    [Pg.12]    [Pg.24]    [Pg.114]    [Pg.316]    [Pg.50]    [Pg.364]    [Pg.234]    [Pg.537]    [Pg.333]    [Pg.90]    [Pg.403]    [Pg.221]    [Pg.584]    [Pg.205]    [Pg.6540]    [Pg.4]    [Pg.111]    [Pg.114]    [Pg.150]    [Pg.156]   
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Applicability of the fundamental equation

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