Optimization experimental method

In optimizing a method, we seek to find the combination of experimental parameters producing the best result or response. We can visualize this process as being similar to finding the highest point on a mountain, in which the mountain s topography, called a response surface, is a plot of the system s response as a function of the factors under our control. 

A kinetic method for the determination of 2,4-dinitrophenol is proposed. The method is based on the inhibiting effect of 2,4-dinib ophenol on the Mn(II) catalysis of the oxidation of malachite green with potassium periodate. The reaction was followed spectrophotometrically at 615 nm. The optimal experimental conditions for the determination of 2,4-dinitrophenol were established under the optimal reaction conditions ... 

If the sequence of a protein has more than 90% identity to a protein with known experimental 3D-stmcture, then it is an optimal case to build a homologous structural model based on that structural template. The margins of error for the model and for the experimental method are in similar ranges. The different amino acids have to be mutated virtually. The conformations of the new side chains can be derived either from residues of structurally characterized amino acids in a similar spatial environment or from side chain rotamer libraries for each amino acid type which are stored for different structural environments like beta-strands or alpha-helices. 

Until recently, most CVD operations were relatively simple and could be readily optimized experimentally by changing the reach on chemistry, the activation method, or the deposition variables until a satisfactory deposit was achieved. It is still possible to do just that and in some cases it is the most efficient way to proceed. However, many of the CVD processes are becoming increasingly complicated with much more exacting requirements, which would make the empirical approach too cumbersome. 

Before putting a HEX in operation, it is necessary to characterize its properties in terms of heat and mass transfer, pressure drop, and hydrodynamics. A number of experimental methods have been presented and exemplified. These data are important to perform simulations and to define optimal operating conditions. 

The Simplex optimization method can also be used in the search for optimal experimental conditions (Walters et al. 1991). A starting simplex is usually formed from existing experimental information. Subsequently, the response that plays the... 

Franz et al. [42] reviewed these techniques completely, along with statistical screening techniques and other experimental methods, with an excellent list of publications. A few selected publications from the recent literature demonstrate the wide variety of formulation and processing problems to which these techniques can be applied and the varying methods selected for optimization. 

Table 1 summarizes several of the experimental methods discussed in this chapter. A need exists for new or revised methods for transport experimentation, particularly for therapeutic proteins or peptides in polymeric systems. An important criterion for the new or revised methods includes in situ sampling using micro techniques which simultaneously sample, separate, and analyze the sample. For example, capillary zone electrophoresis provides a micro technique with high separation resolution and the potential to measure the mobilities and diffusion coefficients of the diffusant in the presence of a polymer. Combining the separation and analytical components adds considerable power and versatility to the method. In addition, up-to-date separation instrumentation is computer-driven, so that methods development is optimized, data are acquired according to a predetermined program, and data analysis is facilitated. 

Analytical methods are ripe for attack using Al methods. Capillary electrophoresis is a routine separation technique, but like other separation techniques, its effectiveness is correlated strongly with experimental conditions. Hence it is important to optimize experimental conditions to achieve the maximum degree of separation. Zhang and co-workers41 studied the separation of mixtures in reserpine tablets, in which vitamin B1 and dibazolum may be incompletely separated, as may promethazine hydrochloride and chloroquine... 

Calculation, thermodynamic optimization of phase diagrams. The knowledge of phase equilibria, phase stability, phase transformations is an important reference point in the description and understanding of the fundamental properties of the alloys and of their possible technological applications. This interest has promoted a multi-disciplinary and multi-national effort dedicated not only to experimental methods, but also to techniques of optimization, calculation and prediction of... 

Deming, S.N. (1978), Optimization of Methods, Chapter 2 in Hirsch, R.F., Ed., Proceedings of the Eastern Analytical Symposium on Principles of Experimentation and Data Analysis, Franklin Institute Press, pp. 31-55. 

Wolters, R., and Kateman, G. (1990), The Constmction of Simultaneous Optimal Experimental Designs for Several Polynomials in the Calibration of Analytical Methods, J. Chemometrics, 4, 171-185. 

The proposed technique is based on an extension to time-varying systems of Wiener s optimal filtering method (l-3). The estimation of the corrected chromato gram is optimal in the sense of minimizing the estimation error variance. A test for verifying the results is proposed, which is based on a comparison between the "innovations" sequence and its corresponding expected standard deviation. The technique is tested on both synthetic and experimental examples, and compared with an available recursive algorithm based on the Kalman filter ( ). 

When a new analytical method is being developed, MDOE is extremely useful, since it is able to identify the key experimental factors and the optimal experimental conditions, by performing a minimal number of experiments, that is, with the lowest possible effort and costs. 

Therefore, it became clear that those methods are reliable tools to detect, to analyze and to optimize all sorts of materials, and in many cases they already turn out to be some sort of cheap, fast and reliable alternative to standard experimental methods in materials science. But still, a lot of work is needed to be done in gaining a more profound experience in what could be called materials engineering , which means systematical understanding and development of new nanoscaled materials with definite properties, and in looking for the mechanism of the so called self-assembling of boron- and carbon-based materials to propose, predict and create nanodevices towards manufacturing of useful solids [1]. 

The nucleophilic displacement of halide ions from M—X bonds by carbonylate anions (either mononuclear or polynuclear) is a general synthetic route to metal-metal bonded species (1,2), and numerous hetero-Pt clusters have been obtained in this way. The resulting products are not often those of expected stoichiometry, although under optimized experimental conditions this method can provide very useful syntheses, particularly of high-nuclearity clusters. Some examples are shown in Eqs. (7)—(11) (5,51-54). 

Depending on the required application, three different methods of preparation of DNA films were developed. The optimized experimental conditions used to obtain AFM images are described in Procedure 28 (see in CD accompanying this book). 

Comprehensive experimental and theoretical investigations of self-oscillations in oxidation reactions were begun in the 1970s by Slinko and coworkers (hydrogen oxidation on Ni and Pt). Their experimental methods are the optimal combination of electrothermography (ETM) with continuous measurements of the contact potential difference (CPD) between the catalyst and a reference electrode. It permitted them to observe simultaneously... 

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