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21.
Giuseppina Masotti Biggiogero 《Annali di Matematica Pura ed Applicata》1962,58(1):85-108
Sunto Si dimostra, estendendola, una cospicua formula di Geometria integrale per gli ovali, indicata da C.B.S. Cavallin [la (28)].
Si dimostrano, in modo analogo, due nuove relazioni per gli ovali [(48) e (53)]. Delle predette formule si mettono in evidenza
vari casi particolari notevoli.
A Enrico Bompiani in occasione del suo Giubileo scientifico. 相似文献
22.
We comment on the previous paper by L. Basano. In particular, we show that its Section 2 is kinematically incorrect (the dynamics of a two-body interaction through tachyon exchange, incidentally, has already been thoroughly expounded in one paper of ours). Its Section 1 is simply a rather subjective introduction. As to its Section 3, containing indeed interesting problems, we again briefly refer to our earlier work. Our conclusions are still in favor of “au revoir to tachyons!,” even if it is known that inside our cosmos tachyons are more likely to have a role in physics (e.g., in elementary particle and black-hole physics) as “exchanged objects” rather than as “asymptotically free” objects. 相似文献
23.
Cucinotta V Giuffrida A Grasso G Maccarrone G Mazzaglia A Vecchio G 《Fresenius' Journal of Analytical Chemistry》2001,370(4):363-366
The separation of three pairs of enantiomeric herbicides has been successfully achieved by capillary electrophoresis at two different pH values in the presence of cyclodextrin derivatives previously synthesized in our laboratory. Two of these derivatives constitute a new class of receptor, the hemispherodextrins, in which a trehalose capping moiety is bonded to beta-cyclodextrin. Because of their peculiar structure hemispherodextrins have very promising characteristics and the low receptor concentration required to achieve separation deserves particular interest. 相似文献
24.
V. Cucinotta Alessandro Giuffrida Giulia Grasso Giuseppe Maccarrone Antonino Mazzaglia Graziella Vecchio 《Analytical and bioanalytical chemistry》2001,370(4):363-366
The separation of three pairs of enantiomeric herbicides has been successfully achieved by capillary electrophoresis at two different pH values in the presence of cyclodextrin derivatives previously synthesized in our laboratory. Two of these derivatives constitute a new class of receptor, the hemispherodextrins, in which a trehalose capping moiety is bonded to β-cyclodextrin. Because of their peculiar structure hemispherodextrins have very promising characteristics and the low receptor concentration required to achieve separation deserves particular interest. 相似文献
25.
We study the Riccati equation arising in a class of quadratic optimal control problems with infinite dimensional stochastic
differential state equation and infinite horizon cost functional. We allow the coefficients, both in the state equation and
in the cost, to be random.
In such a context backward stochastic Riccati equations are backward stochastic differential equations in the whole positive
real axis that involve quadratic non-linearities and take values in a non-Hilbertian space. We prove existence of a minimal
non-negative solution and, under additional assumptions, its uniqueness. We show that such a solution allows to perform the
synthesis of the optimal control and investigate its attractivity properties. Finally the case where the coefficients are
stationary is addressed and an example concerning a controlled wave equation in random media is proposed. 相似文献
26.
Giovanni Carlo Alfonso Antonio Turturro Maria Pizzoli Mariastella Scandola Giuseppina Ceccorulli 《Journal of Polymer Science.Polymer Physics》1989,27(6):1195-1208
Thermal measurements were carried out to investigate the macrostructure of as-cast poly(vinylidene fluoride) (PVDF)/poly(vinyl pyrrolidone) (PVP) blends. At high PVP content, above about 70 wt.%, the two components form a homogeneously mixed amorphous phase whose Tg varies with composition. Crystals are formed upon casting mixtures richer in PVDF; these systems exhibit complex thermal behavior that cannot be justified by a simple two-phase model. DSC measurements above room temperature on semicrystalline blends show, in addition to the melting of PVDF crystals at temperatures that decrease on increasing PVP content, a glass transition at about 80°C, independent of composition. Experimental results strongly support the hypothesis that an interphase, composed of essentially undiluted noncrystalline PVDF, is always associated with the lamellar crystals. 相似文献
27.
Guido Barone Giuseppina Castronuouvo Vittorio Elia Maria Teresa Tosto 《Journal of solution chemistry》1986,15(2):199-210
The excess enthalpies of twelve ternary aqueous solutions of alcohols or monosaccharides containing thiourea have been determined by flow microcalorimetry at 25°C. The coefficients of the virial expansion of the excess enthalpies are compared with those reported in the literature for the same ternary solutions containing urea in place of thiourea. The cross-interaction coefficients are positive for the thiourea-alcohol systems and depend on the length and branching of the alkyl chain of the alcohols. On the other hand, they are negative for the thiourea-monosaccharide systems. Thus, thiourea, as urea, can be used as a probe to reveal differences in the behavior of families of solutes characterized by the same functional groups. The results can be interpreted in terms of the relative stabilities of hydration cospheres of hydrophobic or hydrophilic solutes toward a chaotropic agent such as thiourea.Presented at the sixth Italian meeting on Calorimetry and Thermal Analysis (AICAT) held in Naples, December 4–7, 1984. 相似文献
28.
Antonio Roviello Fabio Borbone Antonio Carella Rosita Diana Giuseppina Roviello Barbara Panunzi Antonio Ambrosio Pasqualino Maddalena 《Journal of polymer science. Part A, Polymer chemistry》2009,47(10):2677-2689
The synthesis and the chemical physical characterization of new photoluminescent (PL) chromophores and polymers are reported. Chromophores (oligo‐PPV symmetric derivatives ending with amino groups) are strong blue emitters with a PL quantum yield of ~70% in dioxane solution. They have been used to prepare polyamides by reaction with aliphatic acyl dichlorides in which emitting and non emitting units are alternated. PL properties of the synthesized polyamides have been evaluated in solution and reveal a strong blue emission (PL quantum yield ~60%), To increase the solubility of these systems, oligomers have been purposely prepared and then characterized. They show a peculiar white emission when excited in DMF solution; to get insight into this interesting behavior, asymmetric monoacetylated chromophores have been prepared as model compounds for the chromophoric end groups of the polyamide chains. The emission spectra of these compounds reveal a broad excimeric yellow emission which is responsible, along with the blue emission of the inner chromophoric units, of the overall white emission of the oligomers. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 2677–2689, 2009 相似文献
29.
30.
Umberto Casellato Rodolfo Graziani Giuseppe Maccarrone Angel J. di Bilio 《Journal of chemical crystallography》1986,16(5):695-702
cis-Diaquabis(2,2-bipyridyl)chromium(III) nitrate crystallizes in the mono-clinic system, space groupP21/c, witha=16.102(6),b=10.792(5),c=15.076(6) Å,=112.90(5)°, andZ=4. The saltlike structure was determined from X-ray crystallography and refined toR=7.5% for 3342 observed reflections. The Cr atom is octahedrally surrounded by twocis water molecules and by two chelated 2,2-bypiridyl ligands forming two nearly orthogonal planes. Selected bond distances are: Cr-O, 2.00(1) and 1.98(1) Å, Cr-N, 2.04 Å (mean). 相似文献