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211.
Alessandra Cherubini 《Milan Journal of Mathematics》2007,75(1):305-321
A word w over a finite alphabet Σ is called k-collapsing if for each finite deterministic automaton the inequality holds provided that for some word , depending on . A word over the alphabet Σ is called k-synchronizing if it is a reset word for all synchronizing automata with k + 1 states and input alphabet Σ. The aim of this work is to give the motivations of the interest in these words and to provide
an overview of some results in this area.
Received: May 2007 相似文献
212.
The ring expansion of 3-unsubstituted (R)-aziridine-2-imide-containing dipeptide under acidic conditions gives rise to oxazoline-5-imide regio and stereoselectively, which can be hydrolysed to the dipeptide containing D-isoserine. On the other hand, the ring opening of 3-unsubstituted (R)-aziridine-2-ester dipeptide, easily obtained from the same (R)-aziridine, gives the regioisomeric dipeptide containing D-serine. 相似文献
213.
Massimo Lucarini Alessandra Durazzo Roberta Bernini Margherita Campo Chiara Vita Eliana B. Souto Ginevra Lombardi-Boccia Mohamed Fawzy Ramadan Antonello Santini Annalisa Romani 《Molecules (Basel, Switzerland)》2021,26(21)
The by-products/wastes from agro-food and in particular the fruit industry represents from one side an issue since they cannot be disposed as such for their impact on the environment but they need to be treated as a waste. However, on the other side, they are a source of bioactive healthy useful compounds which can be recovered and be the starting material for other products in the view of sustainability and a circular economy addressing the global goal of “zero waste” in the environment. An updated view of the state of art of the research on fruit wastes is here given under this perspective. The topic is defined as follows: (i) literature quantitative analysis of fruit waste/by-products, with particular regards to linkage with health; (ii) an updated view of conventional and innovative extraction procedures; (iii) high-value added compounds obtained from fruit waste and associated biological properties; (iv) fruit wastes presence and relevance in updated databases. Nowadays, the investigation of the main components and related bioactivities of fruit wastes is being continuously explored throughout integrated and multidisciplinary approaches towards the exploitation of emerging fields of application which may allow to create economic, environmental, and social value in the design of an eco-friendly approach of the fruit wastes. 相似文献
214.
We prove a global existence result for a semilinear degenerate hyperbolic Cauchyproblem with large data, in the case ofa subcritical defocusing power nonlinearity, in 1 and 2 space dimensions. 相似文献
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219.
Bruno Danieli Giordano Lesma Daniele Passarella Davide Prosperi Alessandra Silvani Ezio Bombardelli 《Helvetica chimica acta》1999,82(9):1502-1508
In an attempt to use 3,5-di(tert-butyl)-1,2-benzoquinone for the oxidative deamination of N-deacetylcolchicine ( 4 ) and N-deacetylthiocolchicine (=N-deacetyl-10-demethoxy-10-(methylthio)colchicine; 5 ) to give the corresponding ketones 2 and 3 , the 2H-1,4-benzoxazine-type adducts 8 / 9 and 11 / 12 , respectively, were formed instead, showing a new and unexpected behavior of Corey's reagent. The adducts were separated and spectroscopically characterized, and a plausible scheme of formation is reported. 相似文献
220.
Chiara Dal Bosco Flavia Bonoli Alessandra Gentili Chiara Fanali Giovanni DOrazio 《Molecules (Basel, Switzerland)》2021,26(23)
A novel chromatographic application in chiral separation by using the nano-LC technique is here reported. The chiral recognition of 12 antifungal drugs was obtained through a 75 µm I.D. fused-silica capillary, which was packed with a CSP-cellulose 3,5-dichlorophenylcarbamate (CDCPC), by means of a lab-made slurry packing procedure. The mobile phase composition and the experimental conditions were optimized in order to find the optimum chiral separation for some selected racemic mixtures of imidazole and triazole derivatives. Some important parameters, such as retention faction, enantioresolution, peak efficiency, and peak shape, were investigated as a function of the mobile phase (pH, water content, type and concentration of both the buffer and the organic modifier, and solvent dilution composition). Within one run lasting 25 min, at a flow rate of approximately 400 nL min−1, eight couples of enantiomers were baseline-resolved and four of them were separated in less than 25 min. The method was then applied to milk samples, which were pretreated using a classical dispersive liquid–liquid microextraction technique preceded by protein precipitation. Finally, the DLLME-nano-LC–UV method was validated in a matrix following the main FDA guidelines for bioanalytical methods. 相似文献