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Motivation, developing nature

At the beginning of the orchestral prelude to his opera "Rheingold , Richard Wagner brilliantly shaped the myth of creation in music, which describes nature in its primordial state, at the absolute beginning of all things. For many bars there is no modulation, no chordal variation. Then a chord in E flat minor appears first the tonic can be heard in unfathomable depths, followed by the addition of a fifth, which finally becomes a triad. The nature motive develops as the leitmotif of all creation (Donington, 1976). [Pg.6]

A constant interest in the development of new rapid methodologies for the preparation of oxazole hbraries is motivated by their presence in numerous biologically active natural products. Janda and coworkers were hrst to show that oxazoles can be obtained by microwave-assisted treatment of polymer-bound a-acylamino-/f-ketoesters with Burgess reagent [68]. Hydroxybutyl-functionalized /anda/el resin was used for this investigation, with key steps being monitored by on-bead FT-IR. First, a resin-bound acetoacetate was pre-... [Pg.94]

The increase in the price of oil and natural gas motivates the chemical industry to develop processes that use alternative raw materials and to develop efficient and economical processes for liquid fuels synthesis from coal and natural gas. An innovative promising approach for producing gasoline from methane is presented in [5]. Other important tasks are development of efficient methods for producing liquid fuels from unconventional sources such as oil shale, tar sands, and deep-sea methane hydrates. [Pg.4]

In this study the problem of estimating an unknown function from its examples is revisited. Its mathematical description is attempted to map as closely as possible the practical problem that the potential NN user has to face. The objective of the chapter is twofold (1) to draw the framework in which NN solutions to the problem can be developed and studied, and (2) to show how careful considerations on the fundamental issues naturally lead to the Wave-Net solution. The analysis will not only attempt to justify the development of the Wave-Net, but will also refine its operational characteristics. The motivation for studying the functional estimation problem is the derivation of a modeling framework suitable for process control. The applicability of the derived solution, however, is not limited to control implementations. [Pg.161]

Of particular concern was the finding of a suitable catalyst Owing to the scouting nature, virtually no know-how base was available that time. The investigation gave highly valuable hints for later catalyst development. Actually, they motivated a search for catalysts of higher porosity and better defined composition. As a result, anodically oxidized alumina supports for catalysts were developed (see Sections 3.1 and 3.4.2). [Pg.316]

For similar motivations, there are limited incentives to develop an alternative SCR process for stationary sources based on methane (CH4-SCR) or other HCs, or based on NTP technologies, if not for specific, better applications. The situation is instead quite different for mobile sources, and in particular for diesel engine emissions. The catalytic removal of NO under lean conditions, e.g. when 02 during the combustion is in excess with respect to the stoichiometric one (diesel and lean-burn engines, natural gas or LPG-powered engines), is still a relevant target in catalysis research and an open problem to meet future exhaust emission regulations. [Pg.6]

Our main motivation to develop the specific transient technique of wavefront analysis, presented in detail in (21, 22, 5), was to make feasible the direct separation and direct measurements of individual relaxation steps. As we will show this objective is feasible, because the elements of this technique correspond to integral (therefore amplified) effects of the initial rate, the initial acceleration and the differential accumulative effect. Unfortunately the implication of the space coordinate makes the general mathematical analysis of the transient responses cumbersome, particularly if one has to take into account the axial dispersion effects. But we will show that the mathematical analysis of the fastest wavefront which only will be considered here, is straight forward, because it is limited to ordinary differential equations dispersion effects are important only for large residence times of wavefronts in the system, i.e. for slow waves. We naturally recognize that this technique requires an additional experimental and theoretical effort, but we believe that it is an effective technique for the study of catalysis under technical operating conditions, where the micro- as well as the macrorelaxations above mentioned are equally important. [Pg.278]

The method used for the safe installation of pressure relief devices is illustrated in Figure 8-1. The first step in the procedure is to specify where relief devices must be installed. Definitive guidelines are available. Second, the appropriate relief device type must be selected. The type depends mostly on the nature of the material relieved and the relief characteristics required. Third, scenarios are developed that describe the various ways in which a relief can occur. The motivation is to determine the material mass flow rate through the relief and the physical state of the material (liquid, vapor, or two phases). Next, data are collected on the relief process, including physical properties of the ejected material, and the relief is sized. Finally, the worst-case scenario is selected and the final relief design is achieved. [Pg.353]

A recent and very promising application of the reachability analysis of TA is scheduling. This development, however, required the introduction of the notion of cost. In contrast to the verification of whether a behavior fulfills a specification or not, costs introduce a quantitative measure to evaluate the individual behaviors. Successful applications of priced TA [15, 16] by using the standard and a special version of Uppaal are documented in [17-19]. The first application to deterministic job-shop scheduling was published by Abdeddaim [20] and Abdeddaim and Maler [21], In order to further motivate the use of TA, the next section shows how the schedule in Figure 10.2 and the plant on which the operations are scheduled naturally translate into a set of timed automata. [Pg.220]

RP-HPLC has been applied for the determination of betalain pigments in various plants too. The researches were motivated by the commercial importance of betalain pigments as natural food colourants. An RP-HPLC method was developed for the measurement of betalain pigments in prickly pear (Opuntia ficus-indica) fruits. [Pg.331]


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See also in sourсe #XX -- [ Pg.2 , Pg.3 ]




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