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51.
Bruschi L Fois G Mistura G Tormen M Garbin V di Fabrizio E Gerardino A Natali M 《The Journal of chemical physics》2006,125(14):144709
We have measured the adsorption of argon films on arrays of microscopic nonlinear cusps and of semicircular channels. In the former case, we observe a distinct crossover from a planarlike to a geometry dependent growth behavior near liquid-vapor bulk coexistence, characterized by a growth exponent chi equal to -0.96+/-0.04 in very good agreement with the predictions of a recent scaling theory [C. Rascon and A. O. Parry, J. Chem. Phys. 112, 5175 (2000)]. The crossover location is also consistent with theory. Instead, on the concave channels we find a much steeper growth near saturation that may signal the formation of two menisci at both sides of the channel bottom. 相似文献
52.
Dattilo D Armelao L Maggini M Fois G Mistura G 《Langmuir : the ACS journal of surfaces and colloids》2006,22(21):8764-8769
We report the immobilization of a fulleropyrrolidine, bearing a dec-9-ynyl functionality, on silicon surfaces through a thermal hydrosilylation protocol. Contact angle measurements on porous silicon (PS) surfaces reveal an unusual dependence of the angle with the PS roughness that apparently contradicts Wenzel's formula. This result has been explained by an extension of Wenzel's model in which the critical angle, which discriminates between the hydrophilic/hydrophobic character of a solid material, is substantially reduced below 90 degrees by surface roughness. 相似文献
53.
Giampaolo Cicogna 《Nonlinear dynamics》2012,67(4):2909-2912
This short note completes the symmetry analysis of a class of quasi-linear partial differential equations considered in the
previous paper (Nonlinear Dynamics 51: 309–316, 2008): it deals with an “exceptional” Lie point symmetry which is admitted only if the involved parameters are fixed by precise
relationships. The peculiarity of this symmetry is enhanced by the fact that, combined with the presence of a conditional
symmetry of “weak” type, it leads to a family of solutions which include, as a particular case, a relevant solution of the
Grad–Schlüter–Shafranov equation, well known in plasma physics. 相似文献
54.
A Terenzi C Ducani V Blanco L Zerzankova AF Westendorf C Peinador JM Quintela PJ Bednarski G Barone MJ Hannon 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(35):10983-10990
The interaction with native DNA of a 2,7-diazapyrenium-based ligand 1 and its Pt(II) rectangular metallacycle 2 is explored through circular and linear dichroism and fluorescence spectroscopies. The metal-free ligand 1 binds through intercalation, with a binding constant of approximately 5×10(5) M(-1) , whereas the metallacycle 2 binds and bends the DNA with a binding constant of 7×10(6) M(-1) . PCR assays show that metallo-supramolecular box 2 interferes with DNA transactions in vitro whereas the intercalator 1 does not. The metallacycle is active against four human cancer cell lines, with IC(50) values ranging between 3.1 and 19.2?μM and shows similar levels of efficacy, but a different spectrum of activity, to cisplatin. 相似文献
55.
Consider the Bayes problem in which one has to discriminate if the random unknown initial state of a stochastic process is distributed according to either of two preassigned distributions, on the base of the observation of the first‐passage time of the process through 0. For processes whose first‐passage times to state 0 are increasing in the initial state according to the likelihood ratio order, such problem is solved by determining the Bayes decision function and the corresponding Bayes error. The special case of fixed initial values including a family of first‐passage times with proportional reversed hazard functions is then studied. Finally, various applications to birth‐and‐death and to diffusion processes are discussed. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
56.
Giampaolo Cicogna 《Nonlinear dynamics》2008,51(1-2):309-316
We consider the problem of performing the preliminary “symmetry classification” of a class of quasi-linear PDE’s containing
one or more arbitrary functions: we provide an easy condition involving these functions in order that nontrivial Lie point
symmetries be admitted, and a “geometrical” characterization of the relevant system of equations determining these symmetries.
Two detailed examples will elucidate the idea and the procedure: the first one concerns a nonlinear Laplace-type equation,
the second a generalization of an equation (the Grad–Schlüter–Shafranov equation) which is used in magnetohydrodynamics. 相似文献
57.
Summary Noise effects on phase lockings in a system consisting of a piecewise-linear van der Pol relaxation oscillator driven by a
periodic input are studied. The problem of finding the period of the oscillator is reduced to the first-passage-time problem
of the Ornstein-Uhlenbeck process with time-varying boundary. Using the probability density functions of the first-passage
time, the operator which governs a transition of an input phase density after one cycle of the oscillator is defined. Phase
lockings in a stochastic sense are investigated on the basis of the density evolution by the operator.
Paper presented at the International Workshop ?Fluctuations in Physics and Biology: Stochastic Resonance, Signal Processing
and Related Phenomena?, Elba, 5–10 June 1994. 相似文献
58.
[reaction: see text] A one-step conversion of carboxylic acids to hydroxamic acids under very mild conditions is described. This simple and efficient method has been applied for the synthesis of enantiopure hydroxamate of alpha-amino acids and peptides. 相似文献
59.
Pier Luigi Ferrarini Claudio Mori Giampaolo Primofiore 《Journal of heterocyclic chemistry》1986,23(2):501-504
Reaction of substituted 7-chloro-1,8-naphthyridines with N-carbethoxypiperazine gave in good yields the corresponding 7-(4-carbethoxypiperazin-1-yl)-1,8-naphthyridines V as potential antihypertensive agents. 相似文献
60.
Pier Luigi Ferrarini Claudio Mori Giampaolo Primofiore Lorella Calzolari 《Journal of heterocyclic chemistry》1990,27(4):881-886
The condensation of 2,6-diaminopyridine and 2-acetamido-6-aminopyridine with β-keto esters in polyphosphophoric acid was studied. In this reaction some 1,8-naphthyridinones, pyrido[1,2-a]pyrimidinones and pyrimido[1,2-a][1,8]naphthyridinones variously substituted were obtained. 相似文献