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Testing and optimizing

There is a growing interest in modeling transition metals because of its applicability to catalysts, bioinorganics, materials science, and traditional inorganic chemistry. Unfortunately, transition metals tend to be extremely difficult to model. This is so because of a number of effects that are important to correctly describing these compounds. The problem is compounded by the fact that the majority of computational methods have been created, tested, and optimized for organic molecules. Some of the techniques that work well for organics perform poorly for more technically difficult transition metal systems. [Pg.286]

Enantioresolution in capillary electrophoresis (CE) is typically achieved with the help of chiral additives dissolved in the background electrolyte. A number of low as well as high molecular weight compounds such as proteins, antibiotics, crown ethers, and cyclodextrins have already been tested and optimized. Since the mechanism of retention and resolution remains ambiguous, the selection of an additive best suited for the specific separation relies on the one-at-a-time testing of each individual compound, a tedious process at best. Obviously, the use of a mixed library of chiral additives combined with an efficient deconvolution strategy has the potential to accelerate this selection. [Pg.62]

For testing and optimizing catalysts, the temperature region just below that where pore diffusion starts to limit the intrinsic kinetics provides a desirable working point (unless equilibrium or selectivity considerations demand working at lower temperatures). In principle, we would like the rate to be as high as possible while also using the entire catalyst efficiently. For fast reactions such as oxidation we may have to accept that only the outside of the particles is used. Consequently, we may decide to use a nonporous or monolithic catalyst, or particles with the catalytic material only on the outside. [Pg.214]

Schutz, E. andFuchs, H. (1982). A new approach to minimizing the number of animals in acute toxicity testing and optimizing the information of the test results. Arch. Toxicol. 51 197— 220. [Pg.174]

A classical Simulated Moving Bed system consists of 4 to 24 columns distributed between 4 zones, in addition to 3 to 5 pumps and valves which connect the different streams between the columns. In general a 4 column SMB should be sufficient to test and optimize the conditions for any given separation problem. The optimal number of columns per zone must be determined in the simulation of the SMB process. The rule is more columns per zone result in a better separation, while too many columns per zone make the system too complex. If an infinite number of columns per zone are used the SMB approaches a TMB. [Pg.216]

Elompart et al. (2001), like Jozefaciuk et al. (2003), use a combined R D section (the preferred format in Analytical Chemistry, the journal that published this article). Their R D section describes both preliminary tests and optimization procedures. Results and discussion of the preliminary tests were presented in excerpt 4C results and discussion of the optimization procedures are presented in excerpt 5A. The optimization process used a factorial design in which five experimental parameters were systematically varied and tested to improve the saponification technique. These variables included the concentration of NaOH, the volume of NaOH, the extraction and stirring times, and the kind of SPME fiber used. [Pg.172]

Soponronnarit, S., Wetchacama, S., Trutassanawin, S. and Jariyatontivait, W., Design, testing, and optimization of vibro-fluidized bed paddy dryer. Drying Tech., 19 (2001) 1891-1908. [Pg.138]

The conversions, selectivities, and kinetics are ideally obtained in a small batch reactor, the operating conditions and catalyst formulation are determined from a bench-scale continuous reactor, the process is tested and optimized in a pilot plant, and finally the plant is constructed and operated. While this is the ideal sequence, it seldom proceeds in this way, and the chemical engineer must be prepared to consider aU aspects simultaneously. [Pg.6]

The design and optimization of a catalyst library for selective hydrogenation is based on the knowledge accumulated in the patent and open literature. In this study we shall focus on catalysts libraries related to supported metals. The catalyst library optimization is performed in an iterative way. First a rough experimental space is created, tested and optimized by HRS. [Pg.304]

Based on the ACR "virtual" catalytic tests and optimization can be performed using HRS (further details are given in the experimental part). Alternatively the whole experimental space can be mapped (see Fig. 1). After subsequent verification step a high resolution experimental space is created and further optimization takes place by HRS creating 1-3 more catalyst generations. After the last verification procedure the... [Pg.305]

The authors thank Ms. Lauren Huffman for her assistance in testing and optimizing this preparation. This work was supported by the National Science Foundation, the Camille and Henry Dreyfus Foundation (JEH is a Camille Dreyfus Teacher Scholar), and the Department of Education GAANN program. [Pg.232]

A med chem route is very rarely amenable to scale-up. This statement is not a condemnation of the chemistry skills of the medicinal chemistry group. Medicinal chemists make molecules for testing and optimization. How the molecules are made is less important than the fact that they are made and made quickly. Only when a compound shows sufficient promise as a candidate is time invested to significantly improve the efficiency of its synthesis. [Pg.338]

Accelerated Development Cycle for New Applications Development of coatings for specific applications is achieved more rapidly than with traditional technologies a large number of samples are quickly prepared for testing and optimization. [Pg.83]

Most of the samples we have analyzed are unsuitable for normal amino acid sequencing because of the low amounts of peptide ( 1 pmole) and the likelihood of multiple peptides being present. Thus we have not attempted to use extraction with trifiuoroacetic acid in combination with amino acid uencing as done by Meyer et al. (2). In cases where amino acid sequence data is needed, we have used some sample to detect the phosphorylation site and the remainder for standard amino acid sequencing. This protocol avoids having to test and optimize a third sequencing cycle which attempts to identify amino acids and collect radioactivity. [Pg.122]

In addition to stringent emissions limits, automakers are also required to extend the useful life of catalytic converters from 50,000 miles to 100,000 miles. Both the catalytic and physical durabilities must be guaranteed over 100,000 miles. To meet these requirements simultaneously, it is imperative to use the systems approach, in which each component of the converter assembly is carefully designed, tested, and optimized. The converter... [Pg.34]

Construction of the pilot plant is complete (7) a photograph is shown in Figure 2. Plant startup is currently underway. A one-year test program is contemplated. During this period all system and component performance tests and optimization studies can be completed. [Pg.181]

Catalyst design involves selecting candidates for further testing and optimization. These may be very close to the final form if based on previously proven catalysts. For novel designs, however, considerable adjustment lies ahead. [Pg.45]

System components were designed, fabricated, tested, and optimized in an iterative process. Primary system components and their functions are listed in Table 1. Each component was tested, redesigned, and tested again until optimum geometries and formulations were determined. Then the components were integrated step by step and tested again. Complete system testing is now underway. [Pg.89]

Research into food safety, both microbial and chemical food safety, has been accompanied by a parallel effort to identify, test, and optimize healthy constituents of foods. The interest in chemicals in foods extends beyond traditional areas - vitamins, essential minerals, etc. - to secondary chemicals sometimes termed phytonutrients or neutraceuticals which have positive health benefits including prevention or alleviation of diabetes, heart disease, Alzheimer s disease, cancer, arthritis, and many other diseases. Food producers use this information as a marketing tool. Compounds of interest include phenols/polyphenols, flavonoids, carotenoids, anthocyanins, and several other classes that function as antioxidants,... [Pg.320]

Based upon the above considerations, it is concluded that the implementation of membrane reactors at an industrial level will be strongly related to further development, testing and optimization of larger scale membrane reactors under real operating conditions, in order to obtain effective performance and cost data to be directly used for techno-economic evaluations by industrial companies. [Pg.262]

II. Test and Optimization of Single-Particle Localization Using a Model System... [Pg.82]

In the framework of Markov models, one has shown in (Do Van et al. 2008c) that perturbation analysis and one of its extension presented in (Cao and Chen 1997) can be very well adapted to reliability or maintenance problems at steady state. The second objective of the present paper is to show how the perturbation technique can he used in order to estimate the DIM of Markov models at steady state by using only a single sample path. Moreover, when perturbation parameters have heen estimated, the DIM of any direction can be easily obtained without additional calculations. As a consequence, difierent maintenance policies or inspection schedules can be easily tested and optimized. [Pg.948]


See other pages where Testing and optimizing is mentioned: [Pg.189]    [Pg.51]    [Pg.125]    [Pg.85]    [Pg.466]    [Pg.171]    [Pg.530]    [Pg.74]    [Pg.6526]    [Pg.615]    [Pg.433]    [Pg.188]    [Pg.155]    [Pg.192]    [Pg.355]    [Pg.6525]    [Pg.213]    [Pg.83]    [Pg.8]    [Pg.85]    [Pg.189]    [Pg.56]    [Pg.499]    [Pg.451]    [Pg.104]    [Pg.55]    [Pg.871]    [Pg.883]   


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