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Normal optimization

The HMBC correlates proton nuclei with carbon nuclei that are separated by more than one bond (Figure 2.2). The experiment is normally optimized for Vch and VcH couplings however, the intensity of the crosspeaks generated by this experiment... [Pg.44]

When equality constraints or restrictions on certain variables exist in an optimization situation, a powerful analytical technique is the use of Lagrange multipliers. In many cases, the normal optimization procedure of setting the partial of the objective function with respect to each variable equal to zero and solving the resulting equations simultaneously becomes difficult or impossible mathematically. It may be much simpler to optimize by developing a Lagrange expression, which is then optimized in place of the real objective function. [Pg.402]

S [89,97-99]. Operation of MTBE degrading bioreactors way outside of the normal optimal range of pH is hkely to affect the process [81]. The degradation of MTBE does not consume or release a net amoimt of protons. Therefore, in most cases pH control is not necessary. However, in the case of acidic groundwater, high dissolved carbon dioxide concentration, or significant nitrification activity, addition of alkahnity is necessary to maintain an optimal reactor pH. [Pg.236]

How much solution we dispense into our NMR tube will affect our ability to quickly adjust the applied field to make it of constant strength in the detected region. In a 5 mm diameter NMR tube, a volume of between 0.6 and 0.7 mL is normally optimal. [Pg.22]

Many of the operating parameters normally optimized for ICP-AES with solution nebulization, are also important in direct sample analyses. These include observation height, RF power, gas flow rates, integration time, and wavelength. In direct sample insertion, sample insertion heights for drying, ashing, and vaporization, rate and duration of insertion, and sample size must also be optimized. [Pg.170]

In addition to the instrumental parameters normally optimized for solution nebulization, the laser ablation technique requires the optimization of the operation of the laser, the volume of the ablation chamber, and the transport distance from the chamber to the plasma. Detection limits reported in the literature indicate that microgram-per-gram determinations are possible. Precision obtained by laser ablation is somewhat degraded when compared to solution nebulization. For a number of different metal samples precisions between 3 and 11% (RSD) are obtained. The linearity of the calibration graphs is typically two or three orders of magnitude. Due to the nature of the laser beam, laser ablation is best suited for area-localized microanalysis. [Pg.173]

The different approaches for studying the travelling salesman problem is a vast subject and only a few important results are mentioned below to supplement the above discussion on the problem on lattices. The normalized optimal contour length per city was calculated by using the universality of the scaling the n-th neighbour distance with the number N of cities where the cities are represented by a set of N points chosen randomly in a unit volume of the )-dimensional hypercube with toroidal boundary conditions [53] = 0.7120 0.0002 in > = 2 and He = 0.6979 0.0002 in > = 3. The mean-field approach [54] in the limit N 00 gives... [Pg.297]

Commercial preamplifier-discriminator combinations come in both fixed threshold and variable threshold versions the former is normally optimized by the manufacturer. In practice, a discriminator threshold level of 2-20 mV offers optimal performance at a lower threshold the electronics would become susceptible to electric-noise interference, and higher thresholds would require higher gain to be achieved by the detector itself and by the preamplifier stage. [Pg.214]

Figure 8.2 depicts the normalized light transmittance TV) of the 90° TN cell at three primary wavelengths R = 650, G = 550, and B = 450 nm. Since the human eye is most sensitive at green, we normally optimize the cell design at i = 550 nm. From Equation (8.4), the first 71 = 1 occurs at dAn 480 nm. The color dispersion (i.e. the wavelength dependency of the light transmittance) at = 0 is not too sensitive to dAnIX beyond the first minimum. Therefore, the TN cell can be treated as an achromatic half-wave plate. The response time depends on the cell gap and... [Pg.237]

A8-2. Evaluate F and f with xj/ = l/. jrexp(—r) for the Li + ion. From these, establish the optimum scale factor r) and write down the expression for the normalized optimized rp-j, and the optimized energy Ej,. Compare these results with the eigenfunction for Li +. [Pg.628]

As stated in Chapter 1, control refers to a closed-loop system where the desired operating point is compared to an actual operating point and a knowledge of the error is fed back to the system to drive the actual operating point towards the desired one. However, the optimal control problems we consider here do not fall under this definition of control. Because the decision variables that will result in optimal performance are time-dependent, the control problems described here are referred to as optimal control problems. Thus, use of the control function here provides an open-loop control. The dynamic nature of these decision variables makes these problems much more difficult to solve as compared to normal optimization where the decision variables are scalar. [Pg.58]

The PCAD subsystem is normally optimized to operate within a narrow band of frequency and voltage While some deviation might be allowable, speed changes as large as those shown in Table 8-3 would produce voltage and frequency values that would require alternate designs for any power... [Pg.285]


See other pages where Normal optimization is mentioned: [Pg.200]    [Pg.599]    [Pg.201]    [Pg.61]    [Pg.68]    [Pg.138]    [Pg.188]    [Pg.59]    [Pg.172]    [Pg.171]    [Pg.809]    [Pg.219]    [Pg.30]    [Pg.809]    [Pg.1194]    [Pg.3]    [Pg.262]    [Pg.213]   
See also in sourсe #XX -- [ Pg.136 , Pg.142 ]




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Optimization in Normal-Phase HPLC

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