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81.
Mauro Picone 《Annali di Matematica Pura ed Applicata》1929,7(1):145-192
Sunto. Si conseguono semplici formole generali maggioranti gli integrali, soggetti ad assegnate condizioni al contorno atte a determinarli,
delle equazioni totalmente paraboliche alle derivate parziali del second'ordine in due o più variabili indipendenti. La ricerca
offre numerosi nuovi risultati, fra i quali, per esempio, quelli concernenti il comportamento all'infinito degli integrali;
il teorema d'unicità per l'annoso problema della propagazione del calore in un mezzo conduttore illimitato, senza l'aggiunta
di ulteriori ipotesi — affatto estranee al punto di vista fisico — sul comportamento all'infinito delle derivate della soluzione;
le condizioni atte a determinare ? in grande ? gli integrali delle equazioni lineari alle derivate parziali del primo ordine,
ecc.
Insignita del premio Tenore dall'Accademia Pontaniana di Napoli, nella seduta del 10 giugno 1928. 相似文献
82.
Mauro Cerasoli 《Journal of Mathematical Analysis and Applications》1983,94(1):150-165
In occupancy problems we randomize the number of balls with a Poisson process of intensity α. Thus some classical formulas are very easily demonstrated and generalized with the aid of inclusion-exclusion principle. Then we give a general theorem to calculate the distributions and moments of particular random variables or waiting times when infinite balls are considered. This theorem can be applied to the well-known birthday and coupon collectors problems. 相似文献
83.
Sfarra Stefano Regi Mauro Tortora Mariagrazia Casieri Cinzia Perilli Stefano Paoletti Domenica 《Journal of Thermal Analysis and Calorimetry》2018,132(2):1367-1387
Journal of Thermal Analysis and Calorimetry - The aim of this work is to evaluate the potentiality of a multi-technique nondestructive approach for characterizing the state of conservation of... 相似文献
84.
Dr. Giuseppe Ferrauto Dr. Daniela Delli Castelli Dr. Loredana Leone Prof. Mauro Botta Prof. Silvio Aime Dr. Zsolt Baranyai Prof. Lorenzo Tei 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(16):4184-4193
The new ligand HPDO3MA [(R,R,R,R)-10-(2-hydroxypropyl)-α,α′,α′′-trimethyl-1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid] was designed to combine and optimize the chemical properties of the macrocyclic ligands HPDO3A and DOTMA. The presence of the methyl groups on the acetic pendant arms of HPDO3A is expected to rigidify the structure of the ligand and favor an increase of the kinetic inertness of the Ln complexes. 1H NMR spectra of Eu(HPDO3MA) displayed the presence of two pairs of diastereoisomers: SAP (square antiprismatic) and TSAP (twisted square antiprismatic) isomers (56 and 44 %, respectively). In addition, 1H and 17O relaxometric NMR studies of Gd(HPDO3MA) showed approximately a 10 % increase in relaxivity and a faster water exchange rate with respect to Gd(HPDO3A). Moreover, a detailed chemical exchange saturation transfer (CEST) characterization of Yb(HPDO3MA) displayed a sensitivity about two times larger than that of Yb(HPDO3A) both in phantom and in cell labeling experiments. Finally, the kinetic inertness of Yb(HPDO3MA) was measured to be twice as high as that of Yb(HPDO3A), with a dissociation half-life at physiological pH of about 2500 years. 相似文献
85.
Faisal Zeeshan Joanna Hoszowska Jean-Claude Dousse Dimosthenis Sokaras Tsu-Chien Weng Roberto Alonso-Mori Matjaz Kavčič Mauro Guerra Jorge Miguel Sampaio Fernando Parente Paul Indelicato José Pires Marques José Paulo Santos 《X射线光谱测定》2019,48(5):351-359
We report on measurements of the Kβ diagram, valence-to-core (VtC), and hypersatellite X-ray spectra induced in metallic Cr by photon single and double K-shell ionization. The experiment was carried out at the Stanford Synchrotron Radiation Lightsource using the seven-crystal Johann-type hard X-ray spectrometer of the beamline 6-2. For the Kβ diagram and VtC transitions, the present study confirms the line shape features observed in previous works, whereas the Khβ hypersatellite transition was found to exhibit a complex spectral line shape and a characteristic low-energy shoulder. The energy shift of the hypersatellite relative to the parent diagram line was deduced from the measurements and compared with the result of extensive multiconfiguration Dirac–Fock (MCDF) calculations. A very good agreement between experiment and theory was found. The MCDF calculations were also used to compute the theoretical line shape of the hypersatellite. A satisfactory agreement was obtained between the overall shapes of the experimental and theoretical spectra, but deviations were observed on the low- and high-energy flanks of the hypersatellite line. The discrepancies were explained by chemical effects, which were not considered in the MCDF calculations performed for isolated atoms. 相似文献
86.
Cyrille Charpentier Jérémy Salaam Dr. Aline Nonat Fabio Carniato Dr. Olivier Jeannin Dr. Isabel Brandariz Dr. David Esteban-Gomez Dr. Carlos Platas-Iglesias Dr. Loïc J. Charbonnière Prof. Mauro Botta 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(24):5407-5418
The heptadentate ligand L was shown to form an extremely stable Gd complex at neutral pH with a pGd value of 18.4 at pH 7.4. The X-ray crystal structures of the complexes formed with Gd and Tb displayed two very different coordination behaviors being, respectively, octa- and nonacoordinated. The relaxometric properties of the Gd complex were studied by field-dependent relaxivity measurements at various temperatures and by 17O NMR spectroscopy. The pH-dependence of the longitudinal relaxivity profile indicated large changes around neutral pH leading to a very large value of 10.1 mm −1⋅s−1 (60 MHz, 298 K) at pH 4.7. The changes were attributed to an increase of the hydration number from one water molecule in basic conditions to two at acidic pH. A similar trend was observed for the luminescence of the Eu complex, confirming the change in hydration state. DOSY experiments were performed on the Lu analogue, pointing to the absence of dimers in solution in the considered pH range. A breathing mode of the complex was postulated, which was further supported by 1H and 31P NMR spectroscopy of the Yb complex at varying pH and was finally modeled by DFT calculations. 相似文献
87.
88.
Gianluca Ambrosi Mauro Micheloni Daniele Paderni Mauro Formica 《Supramolecular chemistry》2020,32(2):139-149
ABSTRACTThe new macrocyclic ligand L (28,29-dimethoxy-27-oxa-8,11,14,17,25,26-hexaazatetracyclo[22.2.1.1(2,6).1(19,23)]nonacosa-2,4,6(28),19,21,23(29),24,26(1)-octaene) has been synthesised. It contains a tetramine chain and the 2,5-bis(2-methoxy-3-metyl-phenyl)-1,3,4-oxadiazole (PPD-OMe) chromophore, acting as coordinating and sensing units, respectively.The fluorescent emission of L depends on the pH being highly fluorescent at pH = 2 and not emitting from pH >10. The studies highlighted that L is a PET mediated emitting chemosensor, being the PET effect regulated by the degree of the tetraamine protonation.L coordinates metal ions (Cu(II), Zn(II) and Cd(II)) in water giving rise to an OFF-ON fluorescent response for the presence of Zn(II) ion thus signalling its presence in the medium. This response is particularly notable at pH = 9 allowing to extend the Zn(II) sensing also in the alkaline pH field. 相似文献
89.
This note addresses the issue as to which ceers can be realized by word problems of computably enumerable (or, simply, c.e.) structures (such as c.e. semigroups, groups, and rings), where being realized means to fall in the same reducibility degree (under the notion of reducibility for equivalence relations usually called “computable reducibility”), or in the same isomorphism type (with the isomorphism induced by a computable function), or in the same strong isomorphism type (with the isomorphism induced by a computable permutation of the natural numbers). We observe, e.g., that every ceer is isomorphic to the word problem of some c.e. semigroup, but (answering a question of Gao and Gerdes) not every ceer is in the same reducibility degree of the word problem of some finitely presented semigroup, nor is it in the same reducibility degree of some non-periodic semigroup. We also show that the ceer provided by provable equivalence of Peano Arithmetic is in the same strong isomorphism type as the word problem of some non-commutative and non-Boolean c.e. ring. 相似文献
90.
Computational Management Science - In this paper, we consider a random vector $$X=left( X_1,X_2right) $$ following a multivariate Skew Normal distribution and we provide an explicit formula for... 相似文献