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61.
Mariapompea Cutroneo Vladimír Havránek Alfio Torrisi Anna Mackova Petr Malinsky Petr Slepicka Zdenek Sofer Lorenzo Torrisi 《Surface and interface analysis : SIA》2020,52(12):1156-1162
A hybrid film consisting of graphene oxide covered with poly(dimethylsiloxane) was prepared via spin coater and followed by thermal annealing to improve the bond strength of the polymerized systems. Direct patterning on both graphene oxide and hybrid graphene oxide–poly(dimethylsiloxane) foils by ion microbeam was performed to induce localized reduction in the ion irradiated material. It is well established that the ion irradiation of graphene oxide induces modifications in its electrical, mechanical, and optical properties and disorder in the carbon crystal structure and defect production. The presence of poly(dimethylsiloxane) can be useful as it confers flexibility to the produced pattern and oxygen permeability from the graphene oxide surface. Rutherford backscattered spectroscopy and elastic recoil detection analysis were performed to evaluate the compositional changes in the composite. Atomic force microscopy studied the pattern fidelity. The electrical conductivity of the hybrid material was used to evaluate the changes induced during the proton irradiation of the material. 相似文献
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An ns Nd:YAG pulsed laser was used to deposit thin films in a vacuum and to generate nanoparticles in the water of Ni, Ti, and NiTi alloys. Laser ablation was measured in terms of removing mass per laser pulse. The laser-generated plasma in vacuum was characterized in terms of temperature and energy of emitted particles. The ablation in water produces nanoparticles with dimensions of the order of 25 nm and solutions with concentrations of the order of some mg/ml. The NiTi alloy stoichiometry is well reported in the deposited thin film and in the composition of the produced nanoparticles. 相似文献
64.
In the present work a general theoretical framework for coupled dimensionally-heterogeneous partial differential equations
is developed. This is done by recasting the variational formulation in terms of coupling interface variables. In such a general
setting we analyze existence and uniqueness of solutions for both the continuous problem and its finite dimensional approximation.
This approach also allows the development of different iterative substructuring solution methodologies involving dimensionally-homogeneous
subproblems. Numerical experiments are carried out to test our theoretical results. 相似文献
65.
A measurement system is described that allows an objective review and evaluation of the amount of use by different population groups of provided shade structures. It employs the comparison of the erythemal UV exposure measured with dosimeters to either the vertex or forehead to that in full sun. The technique has been developed using three shade structures and found to provide a linear relationship with an R(2) of 0.99 between the exposure ratio and the time spent in the shade for the solar zenith angle range of 19-53° and for both low- and high-cloud levels. It provides an objective determination of the amount of shade use by population groups that have set periods of time outdoors. 相似文献
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Alfio Giarlotta 《Order》2014,31(2):239-258
A NaP-preference (necessary and possible preference) on a set A is a pair \({\left(\succsim^{^{_N}}\!,\,\succsim^{^{_P}}\!\right)}\) of binary relations on A such that its necessary component \({\succsim^{^{_N}} \!\!}\) is a partial preorder, its possible component \({\succsim^{^{_P}} \!\!}\) is a completion of \({\succsim^{^{_N}} \!\!}\) , and the two components jointly satisfy natural forms of mixed completeness and mixed transitivity. We study additional mixed transitivity properties of a NaP-preference \({\left(\succsim^{^{_N}}\!,\,\succsim^{^{_P}}\!\right)}\) , which culminate in the full transitivity of its possible component \({\succsim^{^{_P}} \!\!}\) . Interval orders and semiorders are strictly related to these properties, since they are the possible components of suitably transitive NaP-preferences. Further, we introduce strong versions of interval orders and semiorders, which are characterized by enhanced forms of mixed transitivity, and use a geometric approach to compare them to other well known preference relations. 相似文献
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In this paper we propose a stabilized conforming finite volume element method for the Stokes equations. On stating the convergence
of the method, optimal a priori error estimates in different norms are obtained by establishing the adequate connection between
the finite volume and stabilized finite element formulations. A superconvergence result is also derived by using a postprocessing
projection method. In particular, the stabilization of the continuous lowest equal order pair finite volume element discretization
is achieved by enriching the velocity space with local functions that do not necessarily vanish on the element boundaries.
Finally, some numerical experiments that confirm the predicted behavior of the method are provided. 相似文献
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