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In this study,the three dimensional nanoscale organization in the photoactive layers of poly(3-hexylthiophene) (P3HT) and a methanofullerene derivative (PCBM) is revealed by transmission electron tomography.After annealing treatment,either at elevated temperature or during slow solvent evaporation,nanoscale interpenetrating networks are formed with high crystalline order and favorable concentration gradients of both components through the thickness of the photoactive layer.Such a tailored morphology acco... 相似文献
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Márcio AF Belo-Filho Franklina MB Toledo Bernardo Almada-Lobo 《The Journal of the Operational Research Society》2014,65(11):1735-1747
Setup operations are significant in some production environments. It is mandatory that their production plans consider some features, as setup state conservation across periods through setup carryover and crossover. The modelling of setup crossover allows more flexible decisions and is essential for problems with long setup times. This paper proposes two models for the capacitated lot-sizing problem with backlogging and setup carryover and crossover. The first is in line with other models from the literature, whereas the second considers a disaggregated setup variable, which tracks the starting and completion times of the setup operation. This innovative approach permits a more compact formulation. Computational results show that the proposed models have outperformed other state-of-the-art formulation. 相似文献
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Petr Harasim 《Applications of Mathematics》2008,53(6):583-598
We propose a theoretical framework for solving a class of worst scenario problems. The existence of the worst scenario is
proved through the convergence of a sequence of approximate worst scenarios. The main convergence theorem modifies and corrects
the relevant results already published in literature. The theoretical framework is applied to a particular problem with an
uncertain boundary value problem for a nonlinear ordinary differential equation with an uncertain coefficient.
This research was supported in part by the project MSM4781305904 from the Ministry of Education, Youth and Sports of the Czech
Republic. 相似文献
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D. Evers G. Denhöfer W. Assmann A. Harasim P. Konrad C. Ley K. Rudolph P. Sperr 《Zeitschrift für Physik A Hadrons and Nuclei》1977,280(3):287-307
The resonance in the12C+12C system atE c.m.=19.3 MeV has been studied in the neutron and proton decay channels. From(p, γ), (n, p) and (n, γ) coincidence measurements high spin states could be localized inA=23 nuclei, in23Mg up to possibly 21/2+. These states were resonantly populated. The present data favorJ π=17/2+ for the 9.61 MeV state in23Mg and therefore also for the probable parent state at 9.81 MeV in23Na. AJ π=12+ assignment to the resonance is supported and evidence was found that the resonant excitation of the lowest 15/2+ and 17/2+ states in mass 23 nuclei is caused by a change of the intrinsic structure of the Yrast levels aroundJ π=15/2+ towards larger deformation. 相似文献
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Rare earth element substituted bismuth ferrites (BiFeO3) are of enormous importance as magnetoelectric materials. The polycrystalline samples of Bi
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La1−x
FeO3 (x=0, 0.2, 0.4, 0.6, 0.8) were prepared by solid-state reaction using standard ceramic method. The single-phase formation of
these compounds was confirmed by X-ray diffraction (XRD) studies. The samples with x=0, 0.2, 0.4, 0.6 are found to be orthorhombic while the sample with x=0.8 is triclinic. The dielectric constant (ε′) and dissipation factor (tan δ) were measured in the frequency range 100 Hz
to 1 MHz at room temperature and as a function of temperature at certain fixed frequencies (1 kHz, 10 kHz, 100 kHz, 1 MHz).
All the samples showed dielectric dispersion. The dielectric constant with temperature shows a broad peak; the peak temperature
shifts with frequency which reflects the relaxor-type behavior. The peak above 600 K in the measured temperature range corresponds
to antiferromagnetic ordering temperature (Néel temperature). The broadness of the peak changes with composition. The ac conductivity
as well as ε′ are found to be maximum for the sample x=0.2 at room temperature. 相似文献
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CoFe2O4-BaTiO3 composites were prepared using conventional ceramic double sintering process with various compositions. Presence of two phases
in the composites was confirmed using X-ray diffraction. The dc resistivity and thermoemf as a function of temperature in
the temperature range 300 K to 600 K were measured. Variation of dielectric constant (ɛ′) with frequency in the range 100 Hz to 1 MHz and also with temperature at a fixed frequency of 1 kHz was studied. The ac
conductivity was derived from dielectric constant (ɛ′) and loss tangent (tan δ). The nature of conduction is discussed on the basis of small polaron hopping model. The static value of magnetoelectric
conversion factor has been studied as a function of magnetic field. 相似文献
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Petr Harasim 《Applications of Mathematics》2011,56(5):459-480
We apply a theoretical framework for solving a class of worst scenario problems to a problem with a nonlinear partial differential
equation. In contrast to the one-dimensional problem investigated by P. Harasim in Appl. Math. 53 (2008), No. 6, 583–598, the two-dimensional problem requires stronger assumptions restricting the admissible set to ensure
the monotonicity of the nonlinear operator in the examined state problem, and, as a result, to show the existence and uniqueness
of the state solution. The existence of the worst scenario is proved through the convergence of a sequence of approximate
worst scenarios. Furthermore, it is shown that the Galerkin approximation of the state solution can be calculated by means
of the Kachanov method as the limit of a sequence of solutions to linearized problems. 相似文献
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