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Relations physics

Development of Process (Matfiematical) Models Constraints in optimization problems arise from physical bounds on the variables, empirical relations, physical laws, and so on. The mathematical relations describing the process also comprise constraints. Two general categories of models exist ... [Pg.742]

It is unclear whether previously published fire risk analyses have adequately ircaicd dependent failures and systems interaetions. Examples of either experienced or postulated system interactions that have been missed include unrelated systems that share common locations and the attendant spatially related physical interactions arising from fire. Incomplete enumeration of causes of failure and cavalier assumptions of independence can lead to underestimation of accident l rci uencies by many orders of magnitude,... [Pg.200]

For the first kind of application, the focus is on certain elements of the HVAC component under consideration. The simulation is used to study and optimize design-specific aspects such as the pipe size and spacing or wetted area and fin geometry in a heat exchanger. This kind of modeling requires detailed knowledge on many input parameters and the related physical processes. [Pg.1072]

Table 2 shows some safety-related physical properties of hydrogen as compared to two commonly accepted fuels, natural gas and gasoline. [Pg.658]

This book focuses on the relationships between the chemical structure and the related physical characteristics of plastics, which determine appropriate material selection, design, and processing of plastic parts. The book also contains an in-depth presentation of the structure-property relationships of a wide range of plastics, including thermoplastics, thermosets, elastomers, and blends. [Pg.418]

To rationalize the isothermal assumption, Dykhuizen 39() discussed two related physical phenomena. First, heat may be drawn out of the substrate from an area that is much larger than that covered by asplat. Thus, the 1 -D assumption in the Stefan problem becomes invalid, and a solution of multidimensional heat conduction may make the interface between a splat and substrate closer to isothermal. Second, the contact resistance at the interface is deemed to be the largest thermal resistance retarding heat removal from the splat. If this resistance does not vary much with substrate material, splat solidification should be independent of substrate thermal properties. Either of the phenomena would result in a heat-transfer rate that is less dependent on the substrate properties, but not as high as that calculated by Madej ski based on the... [Pg.311]

Braams Van Herpen). . . Random Walk and Related Physical Problems (Ree, Ree, 7 259... [Pg.404]

The solute concentration Wg from each run has been expressed as a step function of the distance z, from which (-Wg/Wo) is calculated. The values of all the experimental parameters, D/uL, Dg/uL, Lu, /LD, Cpyti/k and (h f g/yM. ) ( AT) etc. are calculated from the values of the related physical properties in the literature (19). In Figure 3, g is correlated with z/L for all the thirteen runs, for which the values of effective diffusivity Dg in the melted zone have been predicted from the Kraussold correlation (7) using the experimental values of PrGr number and the values of the parameter Pe calculated show that little improvement has been made by using Pe instead of P in the correlation. [Pg.239]

To paraphrase William Osier, If you know alcoholism, you know all of medicine. This observation is particularly pertinent given alcohol s myriad neuropsychiatric manifestations, co-morbid mental disturbances, and complicating medical conditions. The interaction between alcohol and its related physical disturbances requires the careful use of various psychotropics to safely detoxify patients and to help prevent more serious medical or emotional complications. The use of BZDs should only... [Pg.299]

This section deals with chemical aging and related physical phenomena, such as diffusion and embrittlement. Apart from the chemical problem there is mechanical deterioration which is also related to long term environmental effects, but this was covered briefly in the preceding cumulative damage discussion. [Pg.239]

VI. Explanation of Interferometry and Related Physical Optical Effects Using 0(3) Electrostatics... [Pg.79]

VI. EXPLANATION OF INTERFEROMETRY AND RELATED PHYSICAL OPTICAL EFFECTS USING 0(3) ELECTRODYNAMICS... [Pg.113]

In view of the electrophilic character of ground state oxygen atoms in their reactions with olefins, there should be an approximate correlation of the rates with the ionization potentials of the olefins. Such a correlation does exist (27) but it is only approximate (28). Approximate correlations exist also with some other related physical properties (27), such as heats of hydrogenation and spectroscopic excitation energies, and with theoretically derived properties (28) (obtained by molecular or-... [Pg.143]

Anomalous transport features have been reported for an increasing number of (complex) systems. Many of these systems underlie some sort of a generalized limit theorem that is connected with Levy statistics and thus with selfsimilar evolution patterns. This fact is mirrored in the long-time prevalence of power-law time behaviors of the related physical quantities. [Pg.254]

The hydrolysis of proteins yields a complex mixture of amino acids having closely related physical properties. Although a quantitative separation of the individual amino acids can be achieved by chromatographic methods, only in a few cases is the preparative isolation of an individual member worth while. Provided that racemisation is avoided during hydrolysis, however, amino acids are obtained in this way in the optically active form. The normal synthetic products are of course racemic, but they may be resolved by appropriate procedures (e.g. the enzymic method described in Expt 5.221). [Pg.750]

However, mathematical manipulations (in this case, taking logarithms of the observed concentrations or of related physical properties) increase the uncertainty in the result by expanding errors when using imprecise data. This is specially true of data collected towards the end of a reaction when the differences in concentration between successive readings are small and decreasing. [Pg.54]

This scheme differs from the various systems in use in industry and academia in that it uses the mole instead of the cc(STP) to express the quantity of matter being transported, the pascal rather than the atmosphere or the cm. Hg. to express pressure, the meter rather than the mil, the inch, or the centimeter to express length, and the second rather than the day to express time. Our experience indicates that the existing variety of unit systems leads to confusion and that calculations of related physical properties such as permeabilities, diffusion coefficients, and solubilities are easier using the SI units. More modern measurement systems which detect permeants by means of the electrical currents generated by individual atoms are easier to analyze when one uses moles rather than cc(STP) to express the amount of matter undergoing transport. Applications involving the transport of mixed permeant species are also easier to deal with on a molar basis. Conversion tables between the SI units and customary units are provided on the SRM certificate and in the appropriate standards documents (4, 5). ... [Pg.92]

As an example, let us now examine the specific case of particle motion at 25°C and atmosphere pressure. The related physical properties are dp = 0.001 m, pp = 1000 kg-nf p, = 1.145 kg-in. and pg = 1.798 Pa s. The calculated values for the terminal velocity and the operational condition ranges are given in Table 2.2. An important conclusion that can be drawn from the data listed in the fourth column of Table 2.2 is that the Stokes regime cannot exist in co-axial horizontal impinging streams while other regimes are applicable in this kind of impinging stream. [Pg.59]


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