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51.
    
A high throughput catalyst screening is presented employing an evolutionary approach. The method comprises the optimization of initial leads by subjecting the catalysts to iterative rounds of optimization, including structural elaboration of the ligands by creating new focused libraries. Highly modular supramolecular ligands, robotized synthesis combined by high throughput experimentation creates a platform for fast catalyst development. An illustrative example for the asymmetric hydrogenation of cyclic 2,3,3‐trimethyl‐3H‐indole using iridium catalysts is presented. The kinetic investigation of the best catalyst yields an unusual second order in iridium, first order in hydrogen and zeroth order in substrate. Under optimized reaction conditions a TOF of 100 mol mol−1 h−1 with 96% ee could be obtained with the best catalyst. A full catalyst screening and kinetic study was conducted within a three‐week time‐frame.  相似文献   
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The design shear resistance of an existing structure can be evaluated with analytical design procedures and numerical procedures provided by non‐linear finite element analyses. The new fib Model Code 2010 proposes different calculation methods that fall into four different levels of approximation. As the level of approximation rises, so the complexity and the accuracy of the calculated shear resistance increases. Non‐linear finite element analyses belong to the highest level of approximation, but although they are more and more becoming a customary tool in the daily design process, building codes do not provide guidance on how to perform these analyses. This paper describes non‐linear finite element analyses performed on prestressed beams, which underwent shear failure during experimental loading, in order to assess and criticize the finite element approaches. The aim of this work is to propose guidelines for numerical simulations in order to reduce model and user factors. The results obtained from the non‐linear finite element analyses have been compared with the analytical results using different levels of approximation. The design shear resistance obtained with the highest level of approximation, level IV, derived from non‐linear finite element analyses, turned out to be higher than the design shear resistance obtained with analytical procedures (levels I/II/III).  相似文献   
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Due to the rapid development of speech communication interfaces, speech will be a major mode of man-machine communication. Essential to the development of speech input/output applications is the understanding of the techniques and jargon of speech by the application designer who, in most cases, has no formal speech training and, perhaps, little understanding of computers. This paper includes introductory tutorials on speech synthesis and recognition in an attempt to overcome the jargon barrier. A limited number of application examples are presented to stimulate generation of new applications.  相似文献   
56.
Summary An automated method is described for the enzymatic determination of starch in some meat products. After solubilization with dimethylsulfoxide/hydrochloric acid, the starch was automatically determined with amyloglucosidase (EC 3.2.1.3) and hexokinase (EC 2.7.1.1)/glucose-6-phosphate dehydrogenase (EC 1.1.1.49) using a Technicon AutoAnalyzer II System. The analyses could be performed at a rate of forty samples per hour. The results agree very well with those obtained by the polarimetric method.
Eine automatisierte enzymatische Bestimmung der Stärke in Fleischerzeugnissen
Zusammenfassung Eine automatische Methode zur enzymatischen Bestimmung der Stärke in Fleischerzeugnissen wird beschrieben. Nach Lösung in einer Dimethylsulfoxide/Salzsäure-Mischung, wurde Stärke mittels Amyloglucosidase (EC 3.2.1.3) and Hexokinase (EC 2.7.1.1)/Glukose-6-phosphatdehydrogenase (EC 1.1.1.49) mit Hilfe des Technicon AutoAnalyzers II automatisch bestimmt. Diese Methode ermöglicht 40 Proben pro Std. zu untersuchen. Die Ergebnisse stimmen gut mit den Analysenwerten der polarimetrischen Bestimmung überein.
  相似文献   
57.
The surface tree languages obtained by top-down finite state transformation of monadic trees are exactly the frontier-preserving homomorphic images of sets of derivation trees of ETOL systems. The corresponding class of tree transformation languages is therefore equal to the class of ETOL languages.  相似文献   
58.
Composition of top-down tree transducers yields a proper hierarchy of transductions and of output languages. The same is true for ETOL systems (viewed as transducers) and for two-way generalized sequential machines.  相似文献   
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Summary Deterministic substitution of languages means substituting the same word (from a given language) for all occurrences of a symbol. For an arbitrary family K of languages the notion of deterministic K-iteration grammar is introduced, which is essentially the iteration of a finite number of deterministic substitutions of languages from K. The families of languages generated by these grammars are investigated.The work of the first author has been supported by the Netherlands Organization for the Advancement of Pure Research (Z.W.O.)  相似文献   
60.
Designing a drug is the process of finding or creating a molecule which has a specific activity on a biological organism. Drug design is difficult since there are only few molecules that are both effective against a certain disease and exhibit other necessary physiological properties, such as absorption by the body and safety of use. The main problem of drug design is therefore how to explore the chemical space of many possible molecules to find the few suitable ones. Computational methods are increasingly being used for this purpose, among them evolutionary algorithms. This review will focus on the applications of evolutionary algorithms in drug design, in which evolutionary algorithms are used both to create new molecules and to construct methods for predicting the properties of real or yet unexisting molecules. We will also discuss the progress and problems of application of evolutionary algorithms in this field, as well as possible developments and future perspectives.  相似文献   
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