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Chiara B. Vicentini Manuela Mazzanti Carlo F. Morelli Maurizio Manfrini 《Journal of heterocyclic chemistry》2000,37(1):175-180
Ethyl 2-amino-3-methoxycarbonyl-4-oxo-2-pentenoate (3) reacts with hydroxylamine or hydrazines to give isoxazole and pyrazole ortho-dicarboxylic acid esters 4 and 5, respectively. Partial hydrolysis of diesters 4 and 5 afforded the corresponding dicarboxylic acid monoesters 6 and 7. Amidation of the intermediate acid chlorides 8,9 followed by hydrolysis of 4-methylesters 10, 11 gave the title compounds 1 and 2, respectively. 相似文献
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Giampio Bracchi Chiara Francalanci 《Computational & Mathematical Organization Theory》1997,3(3):173-198
This paper proposes a formal model of information processing inorganizations. The model takes a process view of organizations and includesboth structural and IS features of processes. Two structural properties areconsidered, networking and parallelism. Information systems are representedin terms of quantity of information used and level of informationcustomization allowed. Process performance is measured in terms of totalinformation processing capacity and flexibility afforded by a process. Therelationship between structural and information system choices and processperformance is studied by simulating the model for a range of values. Thepaper derives a set of propositions describing the independent and combinedimpact of structural and information system choices on performance. The results suggest the predominance of networking over parallelism and ofinformation customization over information quantity in determininginformation processing capacity. They also show a negative effect ofnetworking on process flexibility and an amplifying effect of networking onthe benefits of information customization. Overall, the findings validatethe interdependence between structural and information system variables indetermining process performance. 相似文献
97.
The total and the sharp character of orthodox quantum logic has been put in question in different contexts. This paper presents the basic ideas for a unified approach to partial and unsharp forms of quantum logic. We prove a completeness theorem for some partial logics based on orthoalgebras and orthomodular posets. We introduce the notion of unsharp orthoalgebra and of generalized MV algebra. The class of all effects of any Hilbert space gives rise to particular examples of these structures. Finally, we investigate the relationship between unsharp orthoalgebras, generalized MV algebras, and orthomodular lattices. 相似文献
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Paola Benzi Elena Bottizzo Chiara Demaria Nicoletta Rizzi 《Journal of Chemical Sciences》2007,119(6):631-635
YBa2Cu3Ox (Y-123) and Bi2Sr2Ca1Cu2Ox (Bi-2212) films on various substrates have been prepared by Metal-Organic Deposition starting from different metallorganic
fluorine-free compounds and using a very simple instrumentation. The processing conditions include a rapid pyrolysis step
in air and an annealing step in oxygen for Y-123 and in air for Bi-2212. The films obtained have been characterized by X-ray
diffraction (XRD) and the formation of a superconducting phase of Y-123 or Bi-2212 was confirmed measuring the critical temperature
(T
c) with Ac-susceptibility and resistive measurements. Microstructure and final cationic ratios have been studied by scanning
electron microscopy (SEM) and energy dispersive spectroscopy (EDS). 相似文献
100.
Martina Mazzoni Lorenzo Franco Alberta Ferrarini Carlo Corvaja Giovanni Zordan Gianfranco Scorrano Michele Maggini 《Liquid crystals》2002,29(2):203-208
A nitroxide [60]fullerene adduct containing a pyrrolidine-1-oxyl group has been synthesized. Its orientational order in the nematic phase of the liquid crystal solvent 4,4'-azoxyanisole (PAA) has been measured from the variation of the EPR spectral parameters on passing from the isotropic to the nematic phase. Highly resolved EPR lines allow for precise evaluation of the shifts of the g , a N and a H values. Since the g and the hyperfine tensors are known, the order matrix could be obtained. This is compared with the one calculated with a theoretical model based on short range solute-solvent interactions, which predicts a considerable degree of orientation of the molecular axes, despite the almost spherical shape of the molecule. The agreement with experimental findings is quite good and it is further improved if a bent structure of the pyrrolidine ring is taken into account. 相似文献