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Multiple theoretical basis

The coefficient actually measures multiple processes (reversible and irreversible adsorption, precipitation, and coprecipitation). Consequently, it is a purely empirical number with no theoretical basis on which to predict adsorption under differing environmental conditions or to give information on the types of bonding mechanisms involved. [Pg.829]

This description is based on the approximation that the cantilever has effectively infinite point mass. A fuller analysis of the cantilever takes into account its distributed mass and multiple vibration modes (Hirsekorn et al 1997). This allows a more rigorous description of the mode of operation of the UFM and the contrast in the images, and also provides the theoretical basis for using the cantilever as a waveguide through which vibrations can be introduced (Inagaki et al. 1998). For the applications to be described in this chapter, the key components of the UFM and the mechanical diode principle are ... [Pg.298]

This chapter describes the fundamental principles of heat and mass transfer in gas-solid flows. For most gas-solid flow situations, the temperature inside the solid particle can be approximated to be uniform. The theoretical basis and relevant restrictions of this approximation are briefly presented. The conductive heat transfer due to an elastic collision is introduced. A simple convective heat transfer model, based on the pseudocontinuum assumption for the gas-solid mixture, as well as the limitations of the model applications are discussed. The chapter also describes heat transfer due to radiation of the particulate phase. Specifically, thermal radiation from a single particle, radiation from a particle cloud with multiple scattering effects, and the basic governing equation for general multiparticle radiations are discussed. The discussion of gas phase radiation is, however, excluded because of its complexity, as it is affected by the type of gas components, concentrations, and gas temperatures. Interested readers may refer to Ozisik (1973) for the absorption (or emission) of radiation by gases. The last part of this chapter presents the fundamental principles of mass transfer in gas-solid flows. [Pg.130]

In cells, improved timing accuracy arises from cascades of phosphorylation events. This insight is in fact the theoretical basis for a recent kinetic model for phototransduction signaling in vertebrate rod cells published by Hamer et al. [76]. It is proposed that multiple, successive phosphorylations of rhodopsin by rhodopsin kinase lead to high accuracy in the single-photon responses of a rod cell. Briefly, if we assume n identical, irreversible phosphorylation steps with only the fully... [Pg.120]

The solution behavior of polymers has been intensively investigated in the past. Dilute solutions, where polymer-polymer interactions may be excluded, have become the basis for the characterization of the primary structure of macromolecules and their dimensions in solution. Besides this "classical" aspect of macromolecular science, interest has focussed on systems, where - due to strong polymer/polymer interactions - association of polymers causes supermolecular structures in homogeneous thermo-dynamically-stable isotropic and anisotropic solutions or in phase-separated multi-component systems. The association of polymers in solutions gives rise to unconventional properties, yielding new aspects for applications and multiple theoretical aspects. [Pg.2]

As with simple regression equations, extrap>olation of a multiple regression equation is unwise unless there is a very sound theoretical basis. It is good practice to quote the ranges of the independent variables that have occurred in the data used for calculating the regression equation, in order to discourage extrapolation. [Pg.77]

These linear kinetic models and diffusion models of skin absorption kinetics have a number of features in common they are subject to similar constraints and have a similar theoretical basis. The kinetic models, however, are more versatile and are potentially powerful predictive tools used to simulate various aspects of percutaneous absorption. Techniques for simulating multiple-dose behavior evaporation, cutaneous metabolism, microbial degradation, and other surface-loss processes dermal risk assessment transdermal drug delivery and vehicle effects have all been described. Recently, more sophisticated approaches involving physiologically relevant perfusion-limited models for simulating skin absorption pharmacokinetics have been described. These advanced models provide the conceptual framework from which experiments may be designed to simultaneously assess the role of the cutaneous vasculature and cutaneous metabolism in percutaneous absorption. [Pg.2423]

In the end, for simple molecules, much like VSEPR we have an orbital hybridization based solely on the number of bonds. (We treat non-bonding pairs of electrons as bonds and multiple bonds as one just as in VSEPR). The fundamental difference in comparison to VSEPR is that we now have a theoretical basis for the assignment. [Pg.119]

In depth discussions of the TCD can be found in most texts on gas chromatography [1-4]. Lawson and Miller [5] have written a review of the TCD, and give multiple references to discussions regarding the TCD. A comparison of the various modes of operation has been made by Wells and Simon [6] which compares the constant voltage, constant current, and constant mean temperature modes of operation on both an empirical and a theoretical basis. [Pg.60]

While there is considerable theoretical basis for vaccination triggering autoimmune phenomena — in many of the same ways as natural infection — the main interest in this area has arisen from public concern (Offit Hackett, 2003). There is a general concern regarding the relationship between autoimmune diseases and vaccination, but large-scale studies have been performed on only two diseases — multiple sclerosis and diabetes mellitus type 1. [Pg.169]

The theory and practical implementation of the Fourier Transform Faradaic Admittance Measurement technique was introduced and developed by Smith and coworkers.This elec-troanalytical technique now rests on a sound theoretical basis and has been proven in many experimental situations. In this method a multiple-frequency perturbation waveform is used and the cell admittance is calculated at each of these frequencies using the measured current and potential. Measurements over a substantial range of frequencies, at least over two orders of magnitude, are required before any conclusive interpretations can be made concerning the mechanism and kinetics of an electrochemical system. The main advantage of this Fourier transform approach is that the cell admittance can simultaneously by measured at a large number of frequencies. [Pg.21]

The proposed kinetic model of the postpolymerization describes the multiple experimental data well and is in good agreement with all the characteristics of the postpolymerization kinetics listed above. However, the introduction of two types of radicals sharply differing by characteristic life times into a kinetic scheme is an inevitable simplification of a real set of characteristic life times of active radicals. Fhrthermore, it cannot be indirectly re-passed on the kinetics of monofunctional monomer postpolymerization which, the same as stationary kinetics, can be characterized by differences from the kinetics of bifunctional monomer postpolymerization. The term hionomolecular chain termination , introduced in Refs. [ 55, 56] as an active center of the radical self-burial act in the act of chain propagation, did not have a theoretical basis via the relation of kx with k. ... [Pg.163]

Methods for the Meesurement of k x. The evaluation procednres and theoretical basis for the determination of transfer coefficients C have been extended and perfected over the past decade and a great number of transfer coefficients have been determined by various research groups [see for example References 490 and 491 or the multiple entries in the Polymer Handbook (492)]. The transfer coefficient is defined by equation 90 as the ratio of the transfer rate coefficient tr to the propagation rate coefficient k. ... [Pg.6981]

This chapter details a theory for decoding the multiplicity of microbial strategies to extract and channel mass and energy flows under simultaneous environmental stresses, with a focus on resource scarcity. Elucidating tradeoffs between resource availability and microbial physiology provides a theoretical basis for systemic analyses of omics data, and a rational basis for controlling miaobes in medical, environmental and industrial applications. [Pg.141]

Development of a theoretical basis for the influence of coordination bonds that are formed by transition metals with functional groups of a monomer or with a polymer radical would ensure the possibility of efficiently regulating the stereochemistry of radical polymerization. Since the corresponding database is absent, we did not focus in this review on the manifestation of different types of unit variability in one metal-containing polymer (e.g., that caused by the different valence states of the transition metal ions in some units and the diversity of their chemical binding in other imits) or on their multiple character of copolymers. [Pg.202]

According to the above method, we can estimate the acceleration coefficient and carry out experiment design and evaluation. We should note that this method is based on the stress reliability prediction method. If the expected value cannot fully reflect the accelerated stress, the use of this method is restricted, such as multiple stress accelerated life test, etc. And for satellite unit, due to the complexity of its failure mechanism, failure rate ratio can only be as a reliability characterization of the product in different conditions but not as an accurate measure of life characteristic value, and there is no accurate theoretical basis. [Pg.1818]


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See also in sourсe #XX -- [ Pg.196 ]




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Theoretical basis

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