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991.
Marco Sangermano Alessandro Chiolerio Giulio Paolo Veronese Luca Ortolani Rita Rizzoli Fulvio Mancarella Vittorio Morandi 《Macromolecular rapid communications》2014,35(3):355-359
A new approach is reported for the preparation of a graphene–epoxy flexible transparent capacitor obtained by graphene–polymer transfer and UV‐induced bonding. SU8 resin is employed for realizing a well‐adherent, transparent, and flexible supporting layer. The achieved transparent graphene/SU8 membrane presents two distinct surfaces: one homogeneous conductive surface containing a graphene layer and one dielectric surface typical of the epoxy polymer. Two graphene/SU8 layers are bonded together by using an epoxy photocurable formulation based on epoxy resin. The obtained material showed a stable and clear capacitive behavior.
992.
Luca Bagnato Lucio De Capitani Antonio Punzo 《Methodology and Computing in Applied Probability》2014,16(3):627-641
This article reviews some nonparametric serial independence tests based on measures of divergence between densities. Among others, the well-known Kullback–Leibler, Hellinger, Tsallis, and Rosenblatt divergences are analyzed. Moreover, their copula-based version is taken into account. Via a wide simulation study, the performances of the considered serial independence tests are compared under different settings. Both single-lag and multiple-lag testing procedures are investigated to find out the best “omnibus” solution. 相似文献
993.
In this work, we prove the existence of linear recurrences of order M with a non-trivial solution vanishing exactly on the set of gaps (or a subset) of a numerical semigroup S finitely generated by a 1<a 2<?<a N and M=a N . 相似文献
994.
We study the existence of positive solutions for systems of second‐order nonlinear ordinary differential equations, subject to multipoint boundary conditions. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
995.
We derive a sharp cusp count for finite volume complex hyperbolic surfaces which admit smooth toroidal compactifications. We use this result, and the techniques developed in Di Cerbo and Di Cerbo (see [5]), to study the geometry of cusped complex hyperbolic surfaces and their compactifications. 相似文献
996.
In this paper, we consider third-order linear recurrences {un}n≥0 satisfying the recurrence relation un+3=un+2+un+1+un for all n≥0 and investigate the multiplicity of its zeros. We prove that {un}n≥0 has zero-multiplicity at most 2, except for nonzero multiples of shifts of the Tribonacci sequence which has zero-multiplicity 4 when the indices are extended to all the integers. 相似文献
997.
Analysis of the Best Double Frequency Policy in the Single Link Problem with Discrete Shipping Times
We study an inventory–transportation problem where one product has to be shipped from an origin to a destination by vehicles of given capacity over an infinite time horizon. The product is made available at the origin and consumed at the destination at the same constant rate. The intershipment time must be not lower than a given minimum value. The problem is to decide when to make the shipments and how to load the vehicles to minimize the sum of the transportation and the inventory costs at the origin and at the destination per time unit. We study the case in which the intershipment time is a multiple of the minimum value, i.e., the problem with discrete shipping times. We show that, in this case, the best double frequency policy has a tight performance bound of about 1.1603 with respect to the optimal periodic policy and of about 1.1538 with respect to the best frequency-based policy. Moreover, we show that, from the worst-case point of view, the best double frequency policy is the optimal frequency-based policy. 相似文献
998.
Over the years Fourier-Transform Infrared (FTIR) spectroscopy has been widely employed in the structural and functional characterization of biomolecules. The introduction of infrared (IR) microscopes and of synchrotron light sources has created expectations that FTIR could become a generally viable technique to study both structure and reactivity in vivo, inside single cells, by performing measurements that up to a few years ago were the preserve of in vitro experiments on purified macromolecules. In this review we present the state-of-the-art in the application of FTIR spectromicroscopy as a technique for the study of structure and dynamics in single cells, we discuss the performance requirements for this application and review developments in sample handling methods. 相似文献
999.
Candeloro P Tirinato L Malara N Fregola A Casals E Puntes V Perozziello G Gentile F Coluccio ML Das G Liberale C De Angelis F Di Fabrizio E 《The Analyst》2011,136(21):4402-4408
Microinjection techniques and Raman spectroscopy have been combined to provide a new methodology to investigate the cytotoxic effects due to the interaction of nanomaterials with cells. In the present work, this novel technique has been used to investigate the effects of Ag and Fe(3)O(4) nanoparticles on Hela cells. The nanoparticles are microinjected inside the cells and these latter ones are probed by means of Raman spectroscopy after a short incubation time, in order to highlight the first and impulsive mechanisms developed by the cells to counteract the presence of the nanoparticles. The results put in evidence a different behaviour of the cells treated with nanoparticles in comparison with the control cells; these differences are supposed to be generated by an emerging oxidative stress due to the nanoparticles. The achieved results demonstrate the suitability of the proposed method as a new tool for nanotoxicity studies. 相似文献
1000.
Dr. Ying Fu Dr. Rina Soni Dr. María J. Romero Dr. Ana M. Pizarro Dr. Luca Salassa Dr. Guy J. Clarkson Jessica M. Hearn Dr. Abraha Habtemariam Prof. Dr. Martin Wills Prof. Dr. Peter J. Sadler 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(45):15199-15209
Four chiral OsII arene anticancer complexes have been isolated by fractional crystallization. The two iodido complexes, (SOs,SC)‐[Os(η6‐p‐cym)(ImpyMe)I]PF6 (complex 2 , (S)‐ImpyMe: N‐(2‐pyridylmethylene)‐(S)‐1‐phenylethylamine) and (ROs,RC)‐[Os(η6‐p‐cym)(ImpyMe)I]PF6 (complex 4 , (R)‐ImpyMe: N‐(2‐pyridylmethylene)‐(R)‐1‐phenylethylamine), showed higher anticancer activity (lower IC50 values) towards A2780 human ovarian cancer cells than cisplatin and were more active than the two chlorido derivatives, (SOs,SC)‐[Os(η6‐p‐cym)(ImpyMe)Cl]PF6, 1 , and (ROs,RC)‐[Os(η6‐p‐cym)(ImpyMe)Cl]PF6, 3 . The two iodido complexes were evaluated in the National Cancer Institute 60‐cell‐line screen, by using the COMPARE algorithm. This showed that the two potent iodido complexes, 2 (NSC: D‐758116/1) and 4 (NSC: D‐758118/1), share surprisingly similar cancer cell selectivity patterns with the anti‐microtubule drug, vinblastine sulfate. However, no direct effect on tubulin polymerization was found for 2 and 4 , an observation that appears to indicate a novel mechanism of action. In addition, complexes 2 and 4 demonstrated potential as transfer‐hydrogenation catalysts for imine reduction. 相似文献