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Linear rectification process

The tensors and 7 constitute the molecular origin of the second-and third-order nonlinear optical phenomena such as electro-optic Pock-els effect (EOPE), optical rectification (OR), third harmonic generation (THG), electric field induced second harmonic generation (EFI-SHG), intensity dependent refractive index (IDRI), optical Kerr effect (OKE), electric field induced optical rectification (EFI-OR). To save space we do not indicate the full expressions for and 7 related to the different second and third order processes but we introduce the notations —(Ajy,ui,cj2) and 7(—a , o i,W2,W3), where the frequency relations to be used for the various non-linear optical processes which can be obtained in the case of both static and oscillating monochromatic fields are reported in Table 1.7. [Pg.39]

In order to account for excess noise inherent in the rectification process, we may consider a simplified model valid at very low power levels. This implies that the detector is a linear power detector exposed to MMW power or oscillating voltage... [Pg.61]

Relaxation methods for the study of fast electrode processes are recent developments but their origin, except in the case of faradaic rectification, can be traced to older work. The other relaxation methods are subject to errors related directly or indirectly to the internal resistance of the cell and the double-layer capacity of the test electrode. These errors tend to increase as the reaction becomes more and more reversible. None of these methods is suitable for the accurate determination of rate constants larger than 1.0 cm/s. Such errors are eliminated with faradaic rectification, because this method takes advantage of complete linearity of cell resistance and the slight nonlinearity of double-layer capacity. The potentialities of the faradaic rectification method for measurement of rate constants of the order of 10 cm/s are well recognized, and it is hoped that by suitably developing the technique for measurement at frequencies above 20 MHz, it should be possible to measure rate constants even of the order of 100 cm/s. [Pg.178]

In a similar manner to that for the absorption column a linear relationship between the compositions of the two phases can be found for extraction and rectification. To illustrate this we will look at a rectification column. The basic process of rectification is when boiling a multicomponent mixture the vapour generated flows upwards countercurrent to the condensate which falls down the column. As the condensate is colder than the vapour, the components with higher boiling points, the least volatile, condense. They release their enthalpy of condensation to the components with the lower boiling points, the so called more volatile components, which are vaporized. This causes the vapour to become rich in the more volatile components while the less volatile components make up the liquid. The... [Pg.95]

The method of linear prediction (LP) can play many roles in processing of NMR data [4,5], from the rectification of corrupted or distorted data, through to the complete generation of frequency-domain data from an FID an alternative to the FT. Here we consider its most popular usage, known as forward linear prediction, which extends a truncated FID. Rather than simply appending zeros, this method, as the name suggests, predicts the values of the missing data... [Pg.57]

Figure 3c shows a potential energy profile sequence that accentuates the normal inward rectification the reason is that [Na+] is high and entry is easy (barrier is low) from the outside and vice versa on the inside. I know of no examples of this behavior in a cell membrane. The delayed rectification of a K+ channel in membranes of squid nerve fibers is of this nature (N process in Fig. 2) but this is undoubtedly due to the opening of more channels rather than the property of a single channel. As mentioned above, the instantaneous current-voltage relation of an open K+ channel is linear. The theory developed here, however, is not directly applicable to K+ channels since the independence assumption does not hold for K+ channels. [Pg.614]

A multiscale Bayesian approach for data rectification of Gaussian errors with linear steady-state models was also presented in this chapter. This approach provides better rectification than maximum likelihood rectification and single-scale Bayesian rectification for measured data where the underlying signals or errors are multiscale in nature. Since data from most chemical and manufacturing processes are usually multiscale in nature due to the presence of deterministic and stochastic features that change over time and/or frequency, the multiscale Bayesian approach is expected to be beneficial for rectification of most practical data. [Pg.434]

S. Ungarala and B.R. Bakshi. Multiscale Bayesian Rectification of Linear and Nonlinear Processes. AIChE Annual Meeting. Dallas. TX. (also available as technical report) (1999). [Pg.435]

Classically, a transducer is a device able to convert energy of one type into energy of other type for instance, a microphone converts pressure vibrations in air into an electrical current. In this case, we extend the use of the term transducer to include, for instance, changes in molecular potentials due to the vibrational movement of the atoms. When comparing the molecular potentials versus the movement of atoms due to their vibrational modes, we find that a linear relation (transduction process) takes place due to the bending mode of the water molecule (Fig. 12.9b). Another transduction is observed, at least for small displacements, from the antisymmetric stretching mode (Fig. 12.9c), and a full rectification can be observed from the symmetric stretching mode (Fig. 12.9d). [Pg.366]

The Kalman filter is an optimal estimator for the estimation of the states of a dynamic system from a set of measurements which are a subset of the set of states (or linear combinations of states). As such it can be used for noise filtering, estimation of unmeasured states, rectification of multiple sensors for the same property, and prediction of future values of states. Kalman filtering has been used in a number of polymerization applications including the estimation of copolymer composition during emulsion copolymerization [28]. One drawback to the Kalman filter is that it incorporates the process model into the filter structure. In many cases a simple observer will suffice. An observer requires model predictions of the process outputs, but the model is not incorporated into the observer structure. The process model can be updated without changing the observer [29]. [Pg.176]

The static and dynamic linear responses, a(0 0) and a( co co), correspond to the so-called static and dynamic polarizabilities, respectively. At second order in the fields, the responses are named first hyperpolarizabilities whereas second hyperpolarizabilities correspond to the third-order responses. Different phenomena can be distinguished as a function of the combination of optical frequencies. So, p(0 0,0), p(—co co,0), p(0 o), — ea), and p(— 2co co,co) are associated with the static, dc-Pockels (dc-P), optical rectification (OR), and second harmonic generation (SHG) processes whereas y(0 0,0,0), y(- ( ( ,0,0), y( 2co co,( ,0), y( co co, — ca, ), and y(— 3 , , ) describe the static, dc-Kerr, electric-field-induced second harmonic generation (EFISHG), degenerate four-wave mixing (DFWM),... [Pg.44]


See other pages where Linear rectification process is mentioned: [Pg.2303]    [Pg.2553]    [Pg.62]    [Pg.62]    [Pg.118]    [Pg.2549]    [Pg.269]    [Pg.129]    [Pg.129]    [Pg.103]    [Pg.424]    [Pg.426]    [Pg.350]    [Pg.145]    [Pg.812]   
See also in sourсe #XX -- [ Pg.142 , Pg.143 ]




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