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91.
Magdalena Sobczak-Kneć Katarzyna Trąbka-Więcław 《Czechoslovak Mathematical Journal》2011,61(3):733-742
Let T be the family of all typically real functions, i.e. functions that are analytic in the unit disk Δ:= {z ∈ ℂ: |z| < 1}, normalized by f(0) = f′(0) − 1 = 0 and such that Imz Im f(z) ⩾ 0 for z ∈ Δ. 相似文献
92.
Aequationes mathematicae - For a family $$(\mathscr {A}_x)_{x \in (0,1)}$$ of integral quasi-arithmetic means satisfying certain measurability-type assumptions we search for an integral mean K such... 相似文献
93.
ABSTRACT High-resolution emission spectrum of the 1–4 band of the B 2Σ+–X 2Σ+ transition of 14C16O+ was observed for the first time by conventional emission spectroscopy. The band spectrum was excited in a water-cooled Geissler lamp filled with commercial gaseous carbon monoxide enriched in about 80% of the radiocarbon 14C. A rotational analysis has been carried out and obtained molecular constants have been merged with previously published data for the B 2Σ+–A 2Πi and A 2Πi–X 2Σ+ transitions. The principal equilibrium constants for the ground X 2Σ+ state obtained from this work are ωe = 2121.7726(98), ωe x e = 13.9055(27), B e = 1.815290(30), αe = 1.6594(33) × 10?2, and γe = ? 0.377(73) × 10?4 cm?1. Also, presently known experimental equilibrium molecular constants of the X 2Σ+ states of the CO+ isotopic molecules are summarized and isotopic dependence of the B e and ω e constants is discussed. 相似文献
94.
Wojciech Paszkowicz Scott M. Woodley Paweł Piszora Bohdan Bojanowski Jarosław Piętosa Yngve Cerenius Stefan Carlson Christine Martin 《Applied Physics A: Materials Science & Processing》2013,112(4):839-845
Elastic properties of CaMnO3 are of primary importance in the science and technology of CaMnO3-based perovskites. From X-ray diffraction experiments performed at pressures up to 100 kbar using a diamond-anvil cell to hydrostatically compress our sample, a bulk modulus, K 0, of 1734(96) kbar was obtained after fitting parameters to the third-order Birch–Murnaghan equation of state. Mean field, semiclassical simulations predict, for the first time, the third-order equation-of-state parameters and show how the bulk modulus increases with pressure (the zero pressure value being 2062.1 kbar) and decreases with the extent of nonstoichiometry caused by the formation of oxygen vacancies. These trends are amplified for the shear modulus. A more accurate model that allows for the explicit reduction of Mn ions, or localization of excess electrons, yields qualitatively similar results. The experimental and calculated axial ratios show the same trends in their variation with rising pressure. 相似文献
95.
P. Kędzia T. Czechowski M. Baranowski J. Jurga E. Szcześniak 《Applied magnetic resonance》2013,44(5):605-618
In this paper we use a simple analysis based on properties of the axial field generated by symmetrical multipoles to reveal all possible distributions of two coaxial pairs of circular windings, which result in systems featuring zero octupole and 32 pole magnetic moments (six-order systems). Homogeneity of magnetic field of selected systems is analyzed. It has been found that one of the derived systems generates homogenous magnetic field whose volume is comparable to that yielded by the eight-order system. The influence of the current distribution and the windings placement on the field homogeneity is considered. The table, graphs and equations given in the paper facilitate the choice of the most appropriate design for a given problem. The systems presented may find applications in low field electron paramagnetic resonance imaging, some functional f-MRI (nuclear magnetic resonance imaging) and bioelectromagnetic experiments requiring the access to the working space from all directions. 相似文献
96.
The anode supported cell for solid oxide fuel cell, as a modification of the traditional Ni-YSZ anode supported on electrolyte, is examined in this work. The materials obtained on the base of citric method are presented and investigated in this work. The materials consisted of 40 wt.% Ni/YSZ, 50 wt.% Ni/YSZ and 60 wt.% Ni/YSZ were obtained. The base Ni/YSZ materials are tested on the two ways: (a) aging tests and (b) sintering tests. All the materials after aging and sintering are tested by the impedance spectroscopy. The results of electrical conductivity for samples before and after aging show that only in the case of 40 wt.% Ni/YSZ, sample loses of metallic conductivity after 500 h of heating. The other samples reveal metallic conductivity even after long period of aging. The tests of sintering temperature show that this process does not affect significantly on electrical conductivity of the materials. 相似文献
97.
Małgorzata Norek Grzegorz Łuka Marek Godlewski Tomasz Płociński Marta Michalska-Domańska Wojciech J. Stępniowski 《Applied Physics A: Materials Science & Processing》2013,111(1):265-271
Luminescent properties of ZnO nanorods covered with Ag nanoparticles are examined. Nanorods were synthesized on AAO templates using Atomic Layer Deposition (ALD) technique. Two types of the samples were prepared with different arrangement of ZnO nanorods and doping conditions. Nanorods of the second type were codoped with Al, to stimulate defect-related emissions. The ZnO material fills heterogeneously the interior of the AAO nanopores and has hexagonal, wurtzite structure. Both types of structures exhibit a broad defect-related emission at about 440 nm, most probably related to recombination at zinc interstitial (Zni) defects. This emission in samples with a random distribution of ZnO:Al nanorods and finer Ag nanoparticles is enhanced by factor of ~2.5 upon Ag deposition. The so-obtained material is interesting from the point of view of its application in blue range emitting diodes. 相似文献
98.
Jędrzej Śniatycki Günter Schwarz Larry Bates 《Communications in Mathematical Physics》1996,176(1):95-115
The structure of the constraint set in the Yang-Mills-Dirac theory in a contractible bounded domain is analysed under the bag boundary conditions. The gauge symmetry group is identified, and it is proved that its action on the phase space is proper and admits slices. The reduced phase space is shown to be the union of symplectic manifolds, each of which corresponds to a definite mode of symmetry breaking.Research partially supported by NSERC Research Grant SAP0008091.Research partially supported by DFG Grant Schw. 485/2-1.Research partially supported by NSERC Research Grant OGP0042416. 相似文献
99.
A new bioinspired nanomaterial has been obtained by chemisorption of folic acid onto nanocrystalline titanium dioxide. The organic chromophore is linked with the semiconductor surface via the glutamate chain and anchored with the carboxylate group. The geometry and electronic structure of the chromophore was studied in detail with DFT. Photoelectrochemical studies revealed photosensitization of the new material towards visible light. The photoelectrodes composed of the folic acid/titanium dioxide hybrid material generated photocurrent over a 300–600‐nm window. Moreover, the direction of the photocurrent could be changed from anodic to cathodic and vice versa by application of the appropriate photoelectrode potential. Photoelectrochemical and spectroscopic studies allowed the elucidation of the mechanism of photocurrent switching. Photoelectrodes composed of folate‐modified titanium dioxide may serve as a simple model of optoelectronic switches and may constitute the basis for molecular photoelectronic devices. 相似文献
100.
W. P. Węglarz A. Jasiński A. T. Krzyżak P. Kozłowski D. Adamek P. Sagnowski J. Pindel 《Applied magnetic resonance》1998,15(3-4):333-341
Diffusion tensor imaging (DTI) of the control and mechanically injured spinal cord of a ratin vitro andin vivo are reported.In vitro experiments were done on a home-built 6.4 T magnetic resonance microscope. Results for formaline-fixed samples show significant differences in diffusion tensor components between gray matter and white matter of the control spinal cord. Moreover, it is shown that already 6–10 min after the injury DTI can detect changes in water diffusion in areas extending far beyond the region of primary tissue damage.In vivo experiments were performed using a 9.4 T Magnex magnet and Bruker Medspec imaging system. Good-quality DTI images, free from motion artifacts were obtained. Results from control samples confirm differences in water diffusion between white matter and gray matter, observedin vitro. In vivo experiments show that characteristic changes in water diffusion observedin vitro 6–10 min after injury are preserved 60–360 min after injury, without significant alteration during this time. 相似文献