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31.
32.
Mega MS Allegrini P Grigolini P Latora V Palatella L Rapisarda A Vinciguerra S 《Physical review letters》2003,90(18):188501
We study the statistical properties of time distribution of seismicity in California by means of a new method of analysis, the diffusion entropy. We find that the distribution of time intervals between a large earthquake (the main shock of a given seismic sequence) and the next one does not obey Poisson statistics, as assumed by the current models. We prove that this distribution is an inverse power law with an exponent mu=2.06+/-0.01. We propose the long-range model, reproducing the main properties of the diffusion entropy and describing the seismic triggering mechanisms induced by large earthquakes. 相似文献
33.
34.
Vito Vitrih 《Annali dell'Universita di Ferrara》2008,54(2):349-359
In this paper, four-pencil lattices on tetrahedral partitions are studied. The explicit representation of a lattice, based
upon barycentric coordinates, enables us to extend the lattice from a single tetrahedron to a tetrahedral partition. It is
shown that the number of degrees of freedom is equal to the number of vertices of the tetrahedral partition. The proof is
based on a lattice split approach.
相似文献
35.
Raymond P. Vito 《International Journal of Non》1974,9(5):325-330
This is a study on the stability of movement of a particle subject to displacement on a plane and linked to two supports fixed by identical non-linear springs. It is demonstrated that even a slight “softening” non-linearity completely modifies the characteristics of the stability of the system. 相似文献
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38.
Serena Fiorito Francesco Epifano Francesca Preziuso Vito Alessandro Taddeo Claudio Santi Salvatore Genovese 《Tetrahedron letters》2017,58(4):371-374
The chromane core is widely represented in nature being part of a wide array of secondary metabolites of plant, fungal, and bacterial origin. In this paper an improved method for the chemical synthesis of differently substituted chromanes is described. Substituted 2H-1-benzopyrans have been synthesized in good to excellent yields (52–81%) by treatment of 3,3-dimethylallyl and propenylbenzene ethers of differently substituted phenols with phenylselenyl chloride. 相似文献
39.
Leydi Erika Sarmiento Mildred Rodríguez Lorenzo Echevarria Vito Lubes 《Journal of solution chemistry》2010,39(10):1484-1491
The complex species formed between vanadium(III) and 1,10-phenanthroline (phen), 2,2′-bipyridine (bipy), and 8-hydroxyquinoline
(8hq) were studied in aqueous solution by means of electromotive forces measurements, emf(H), at 25 °C with 3.0 mol⋅dm−3 KCl as the ionic medium. The potentiometric data were analyzed using the least-squares computational program LETAGROP, taking
into account the hydrolytic vanadium(III) species formed in solution. Analysis of the vanadium(III)–phen system data shows
the formation of [VHL]4+, [V(OH)L]2+, [V2OL2]4+ and [V2OL4]4+ complexes. In the vanadium(III)–bipy system the [VHL]4+, [V(OH)L]2+, [V2OL2]4+ and [V2OL4]4+ complexes were observed, and in the vanadium(III)–8hq system the complexes [V(OH)L]+, [V(OH)2L], [VL2]+ and [VL3] were detected. 相似文献
40.
Pedro R. Aranda Susana Moyano Luis D. Martinez Irma E. De Vito 《Analytical and bioanalytical chemistry》2010,398(2):1043-1048
A new, simple, and selective method for preconcentration and determination of Cr(VI) in aqueous samples. After adsorption
in “batch mode” on Aliquat 336-AC, determinations were made directly on the solid by X-ray fluorescence spectrometry, which
had the advantage of not requiring the step of elution of the chromium retained. The enrichment factor was calculated considering
that the tablets obtained from 10 mL solution of Cr(VI) (1000 μg L-1) had a final thickness of 0.64 mm and a diameter of 16.7 mm; the volume deposited on the pellet was 0.14 cm3. The preconcentration factor obtained was 71-fold, which was highly satisfactory for chromium trace analysis by XRF. Finally,
the method was successfully applied to the determination of Cr(VI) in drinking water samples. 相似文献