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1.
Spinelli E.M. Mayosky M.A. Mantz R.J. 《Circuits and Systems II: Express Briefs, IEEE Transactions on》2006,53(7):572-576
Fully differential filter design is usually made departing from a single-ended prototype. This procedure guarantees the desired differential-mode response, but does not take into account common-mode dynamics, which could present nonacceptable transient responses or stability problems. A state-space design technique, which provides control of both differential and common-mode responses, is proposed. It is based on a feedback topology that allows independent assignment of differential and common-mode eigenvalues. This technique ensures circuit stability and also provides a high common-mode rejection ratio, which is independent of component unbalances. Experimental results on a first-order state-space filter are presented. 相似文献
2.
3.
Domenico Spinelli Giovanni Consiglio Renato Noto 《Journal of heterocyclic chemistry》1977,14(8):1325-1329
The rates of piperidino substitution of some 2-L-3-nitrothiophenes (I) and 2-L-5-nitrothiophenes (II) (L = Cl, Br, I, OC6H4NO2-p, and SO2Ph) have been measured in methanol and in benzene at various piperidine concentrations. The reactivity of compounds (I) is not affected by the piperidine concentration in both methanol and benzene, except for the case of L = I (Ic). Probably due to association effects, the reactivity of Ic in benzene decreases as the piperidine concentration is increased. The reactions of compounds II follow overall second order kinetics in methanol while in benzene a different behaviour is observed as a function of the nature of the leaving group. In fact, the piperidino substitutions of IIa-c (L = Cl, Br, I) are mildly accelerated at high piperidine concentrations (a moderate solvent effect); on the contrary the reactivity of IId and e shows a strong dependence on the piperidine concentration, pointing out a genuine base catalysis. 相似文献
4.
Aude-Emmanuelle Navarro Corinne Moustrou Nicolas Spinelli Bernard Mandrand 《Tetrahedron》2005,61(16):3947-3952
In previous works we have described a fully automated synthesis of new ferrocene labelled oligonucleotides (Fc-ODNs) probes with one or more electroactive markers at different position in the chain. These Fc-ODNs have shown good properties to detect ODN target in solution. Here we describe the post-functionalization of a conducting co-polymer based on ethylenedioxythiophene (EDOT) derivatives by a series of Fc-ODNs. The grafting of the Fc-ODNs probes resulted in the appearance of the ferrocene redox couple which directly confirm the effectiveness of the ODN anchoring compared to traditional approach based on IR spectroscopy and X-ray fluorescence of the films. Moreover, the electrochemical response of the modified electrodes analysed in organic media before and after hybridization with ODN target confirm that properties obtain in solution for Fc-ODNs already exist in the film. The changes in the current intensity were found to be dependant on the structure of the grafted ODN that validate our strategy to synthesize an optimal Fc-ODNs. 相似文献
5.
Domenico Spinelli Anlonino Corrao Vincenzo Frenna Nicol
Vivona Michele Ruccia Giuseppe Cusmano 《Journal of heterocyclic chemistry》1976,13(2):357-360
The rates of the mononuclear heterocyclic rearrangement of the phenylhydrazone of 3-benzoyl-5-phenyl-1,2,4-oxadiazole (1) into 2,5-diphenyl-4-benzoylamino-1,2,3-triazole (II) have heen measured in dioxane/water (50:50, v:v) in the range of pS+ 3.8–12.2 at various temperatures and the activation parameters determined. On the basis of the results obtained, we present evidence for the occurrence of two different types of reaction: the first, base-catalyzed; the second, pS+ -independent. In the base-catalyzed range the catalysis is of the general type. 相似文献
6.
Resinous materials, generally added to drying oils, were often employed as final protective films in paintings, both in tempera and oil techniques. Most of the resins used in fine arts come from exudates of plants. Natural resins are mainly composed by terpenoids. Among these resins, dammar, rosin, mastic, elemi gum, Venice turpentine were frequently employed in easel paintings. The aim of this work is the identification of natural resins in samples collected from works of art. In this paper we propose to use micro-FTIR spectrometry as a preliminary and non destructive technique to detect the presence of resinous materials in microsamples collected from paintings, followed by GC-MS analyses to obtain a precise identification of the resin. To reach this aim commercial resins, employed as standard, were analysed previously by micro-FTIR spectrometry and then analysed by GC-MS chromatography, searching characteristic chemical compounds used as "markers" of resins. The results obtained on standards allowed us to successfully analyse samples collected from two works of art: the "Portrait of a Young Gentleman", by Lorenzo Lotto (XVI century), and the "Madonna with the Infant Jesus and Saints": by Carlo Maratta (XVII secolo). 相似文献
7.
Angelo Mugnoli Domenico Spinelli Giovanni Consiglio Renato Noto 《Journal of heterocyclic chemistry》1988,25(1):177-183
The geometry obtained by a crystal structure determination of the title compounds, as compared with that of the analogous benzene derivatives, along with results of ab initio calculations, is used to interpret the different SNAr reactivities in some thiophene and benzene compounds. The smaller rotation of the nitro groups with respect to the aromatic rings observed in thiophene derivatives should be considered a relevant factor in the higher reactivity in the thiophene series. 相似文献
8.
Cosimelli B Guernelli S Spinelli D Buscemi S Frenna V Macaluso G 《The Journal of organic chemistry》2001,66(18):6124-6129
The synthesis of the title compound (4b) has been completed: its rearrangement (in dioxane/water; 1:1, v/v) into N-(2,4-dinitrophenyl)-5-phenyl-2H-1,2,3-triazol-4-ylurea (7) has been quantitatively studied in a wide reactivity (at 293 K, k(A) 10(-8) -4 s(-1)) and pS+ (4.5-14.1) range and compared with that of the Z-2,4-dinitrophenylhydrazone of 3-benzoyl-5-phenyl-1,2,4-oxadiazole (10), of the 3-(p-nitro)phenylureine of 5-phenyl-1,2,4-oxadiazole (13), and of N-(5-phenyl-1,2,4-oxadiazol-3-yl)-N'-p-nitrophenylformamidine (14). The results (reactivity, occurrence of specific or general base-catalysis, evidence for or absence of rate-limiting constants) have been well interpreted considering the structure of the side-chains involved and the stability of the final rings obtained in the rearrangements. 相似文献
9.
Tatsuhiko Nakano A.C. Spinelli A. Martín A. Usubillaga Andrew T. McPhail Kay D. Onan 《Tetrahedron letters》1982,23(35):3627-3630
cleavage of the epoxide () of methyl (-)-kaur-9(11)-en-19-oate () with boron trifluoride-ether in benzene and in acetic anhydride yielded () and (), respectively. On epoxidation with -chloroperbenzoic acid in the presence of -nitrosomethyl urea, () suffered a backbone rearrangement to form (). 相似文献
10.