Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Advantages of method

A potential advantage of methods based on a series expansion of the free energy is that the convergence of the series is determined by the A dependence of the potential energy function meaning that the efficiency of the approach could be enhanced by a judicious choice of coupling scheme. [Pg.152]

However, compared with the traditional analytical methods, the adoption of chromatographic methods represented a signihcant improvement in pharmaceutical analysis. This was because chromatographic methods had the advantages of method specihcity, the ability to separate and detect low-level impurities. Specihcity is especially important for methods intended for early-phase drug development when the chemical and physical properties of the active pharmaceutical ingredient (API) are not fully understood and the synthetic processes are not fully developed. Therefore the assurance of safety in clinical trials of an API relies heavily on the ability of analytical methods to detect and quantitate unknown impurities that may pose safety concerns. This task was not easily performed or simply could not be carried out by classic wet chemistry methods. Therefore, slowly, HPLC and GC established their places as the mainstream analytical methods in pharmaceutical analysis. [Pg.54]

The advantage of methods obeying Eq. (10.11) over the scaling in Eq. (10.10) seem so obvious that these new methods would appear poised to sweep away the old once they are available. The situation is not quite this simple, however. [Pg.229]

In general, the great advantage of methods based on the 96-well plate is the decrease in sample amount and the large number of compounds tested simultaneously (parallel process). However, to offer a good throughput, the method has to be as generic as possible. [Pg.99]

Equation 38 shows that ASf°[ij, Tmij] is independent of temperature and requires extrapolation of Cp[n] only over the limited temperature range from Tmn to Tmij, and the extrapolated Cp[n] contribution would be partially cancelled by the last term in equation 36 for Tmn < Tm,j. The data base for the application of equation 37 is the measurable activity product at the melting temperature, Tmij, ASf°[ij, TJ] (as discussed earlier), Cps[ij], Cp[i or j], Cps[i or j], and AHm,orj. The advantages of method III are the explicit statement of the principal temperature dependence and the extrapolation of, at most, only the heat capacity of the liquid element. [Pg.150]

Advantages of method when testing complex biochemical mixtures... [Pg.118]

Mukaiyama and co-workers developed a chiral Lewis acid complex 15 consisting of tin (II) triflate and a chiral diamine. An aldol reaction of enol silyl ether 16 and octanal is promoted by 15 to give 17 in a highly diastereo-and enantioselective manner. The enantioface of the aldehyde is selectively activated by coordination with 15. This method is similar to method 3, in that an aldehyde-chiral Lewis acid complex can be regarded as a chiral electrophile. An advantage of method 4 over method 3 is the possible catalytic use of a chiral Lewis acid. In the reaction of Scheme 3.6, 20 mol% of 15 effects the aldol reaction in 76% yield with excellent selectivity.9... [Pg.178]

The rate of suction in filter paper in contact with a dispersion as a function of pH was observed [697] in a specially designed apparatus, originally described and illustrated in [698], and a shallow minimum in suction time was observed at the IEP. A method of determination of the PZC from the filtration rate was proposed in [699]. However, it is difficult to point to any advantage of methods based on filtration rate other than originality. [Pg.89]

The Kohn-Sham orbitals are chosen so that the orbitals are as localized as possible in some well-defined sense this leads to Sy being effectively zero for orbitals centered far from one another. Among the numerous advantages of methods based upon Eq. (81) is that the Pauli principle (idempotency) is automatically satisfied. Also, note that in Eq. (81), the number of localized orbitals, M, can exceed the number of occupied Kohn-Sham orbitals, N/2. [Pg.106]

These examples also feature noncatalytic processes, in particular, crystallization and phase transformation, illustrating the advantages of methods that allow the inspection of solid particles in solution. [Pg.41]

The advantage of method 2 is that no column chromatography separation is required. However, using this procedure Mo3Fepts is contaminated by a few percent of the white iron salt of Fe(pts)2 nH20. [Pg.154]

Isothermal kinetic measurements fall into two categories method 1, in which the rate and extent of reaction at constant temperature are continuously monitored in the DSC and method 2, in which a partially cured sample is heated in the DSC to measure the residual heat of reaction. An advantage of method 1 is the simultaneous measurement of conversion and rate of conversion, which are necessary for some kinetic analyses. It should be noted that vitrification will occur during method 1 measurements if Tcure is less than Tg,. Method 2 has the advantage of simultaneous measurement of and conversion, from which the Tg-conversion relationship can be established. Both thermal and UV cure reactions can be measured by these methods. [Pg.138]

The main advantage of methods using urea are that large quantities of esters can be separated and that with care there is little chance for harm to come to polyunsaturated esters. [Pg.77]

In summary, it may be said that the determination of residual hydrt en peroxide offers no advantage for routine determinations of peroxidase over the more conventional methods employing donor oxidation. And while several authors claim to have found methods of inhibiting catalase action during these assays, no reliable technique to do this has been well substantiated. The advantage of methods which measure residual substrate consists in avoiding any influence of oxidase activity on the results of the assay. [Pg.398]

The main advantage of Method I is that the measured ratio Rfn is calculated. A key disadvantage is that a divider element must be included in the loop, and this element makes the process gain vary in a nonlinear fashion. From Eq. 15-1, the process gain... [Pg.275]

As well as for method (l), the necessity of specific instrumentation is a disadvantage of method (3), but the advantage of method (3) is the shorter treatment time required compared to method (l). As treatment can be performed in the same system as the electrochemical measurements, method (4) is convenient for the use of electrochemistry. [Pg.219]


See other pages where Advantages of method is mentioned: [Pg.71]    [Pg.199]    [Pg.2375]    [Pg.66]    [Pg.169]    [Pg.146]    [Pg.27]    [Pg.42]    [Pg.336]    [Pg.464]    [Pg.402]    [Pg.276]    [Pg.71]    [Pg.108]   
See also in sourсe #XX -- [ Pg.18 ]




SEARCH



Advantages and Disadvantages of the Activation Analysis Method

Advantages and Limitations of Force Field Methods

Advantages and Mutual Comparison of Atomic Spectrometric Methods

Advantages and disadvantages of methods utilising solvents

Advantages and disadvantages of non-parametric methods

Advantages and disadvantages of solvent-free methods

Advantages and limits of the method

Advantages of Standard Methods

Advantages of method when testing complex biochemical mixtures

Advantages of the Method

Alternative methods of sensory testing advantages and disadvantages

Limitations and Advantages of Semi-empirical Methods

Specific advantages of the method

© 2024 chempedia.info