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101.
In this paper, we investigate the growth of two composite entire functions of finite iterated order and a series of comparative growths of logp+qT(r,f(g)) (p,q∈N) with logpT(r,f) and logqT(r,g). At the end of this paper, we apply some growth results into the factorization of the solutions of linear differential equation. We achieve some results which are the improvements and extensions of the previous results. 相似文献
102.
Sean Effinger-Dean 《Journal of Mathematical Analysis and Applications》2006,324(2):1062-1072
We compute the norms of composition operators with rational symbols that satisfy certain properties, extending Christopher Hammond's methods on operators with linear fractional symbols. This leads to a host of new examples of composition operators whose norms are calculable. 相似文献
103.
In this note, some conditions of composition operators on Dτspaces to be bounded are given by means of Carleson measures and pointwisemultipliers, for some ranges of τ. The authors prove that (i) Let 1<τ n+2 and 2k<τ 2k+1 (or 2k-1<τ 2k) for somepositive integer k. Suppose φ=(φ1,...,φn) be aunivalent mapping from B into itself, denote dμj(l)(z)=R(l)φj(z)2(k-l+2)(1-|z|2)2k-τ+1 dν(z) for l=1,2,...,k+1. If μj(l)φ-1 are (τ-2k+2l-4)-Carleson measures for all l, then the composition operator Cφon Dτis bounded; (ii) Let 1<τ n+2, φ=(φ1,...,φn)be univalent and the Fr echet derivativeof φ-1 be bounded onφ(B). If Rφj∈M(Dτ-2) forall j, then the composition operator Cφ on Dτis bounded; (iii) Let τ>n+2 and φ as in (ii).If φj∈Dτ for all j, then the compositionoperator Cφ on Dτ is bounded. 相似文献
104.
Z. Niu P. Zheng Y. Xiao C. Luo K. Zhang J. Zhang L. Zheng Y. Zhang W. Bai 《Materials Today Chemistry》2022
Dielectric capacitors with high energy storage performance show a huge competitive advantage for use in vehicles and power electronics. Here, the (1-x) (0.75Bi0·5K0·5TiO3?0.25BiFeO3) – xSr0.7Bi0·2TiO3 (BKT-BF-xSBT) materials were designed based on the dual optimization strategy of grain size and bandgap. The optimal performance was obtained in the BKT-BF-0.4SBT sample, achieving high energy storage density Wrec of 5.21 J/cm3 and high energy storage efficiency η of 90.87% at 360 kV/cm. The addition of SBT optimized the microstructure and relaxation behavior of BKT-BF ceramic, giving rise to the formation of polar nanoregions (PNRs), small grain size (G), compact grain boundaries, and wide bandgap (Eg) synchronously. Encouragingly, prominent stabilities against temperature, frequency, and cycle numbers, and favorable charge/discharge performance (power density PD ≈ 64.5 MW/cm3, τ0.9 ≈ 90 ns) are also accomplished in designed BKT-based ceramics. These findings indicate that the BKT-BF-xSBT ceramic system has excellent potential in the dielectric energy storage field and also provides a viable prospect for engineering design of high-efficiency lead-free dielectrics via bandgap and grain size. 相似文献
105.
106.
Stevo Stević 《Numerical Functional Analysis & Optimization》2013,34(7-8):959-978
The boundedness and compactness of the generalized composition operator from mixed-norm spaces to the Bloch-type space, the little Bloch-type space, the Zygmund space, and the little Zygmund space are investigated in this paper. 相似文献
107.
Xiangling Zhu 《Numerical Functional Analysis & Optimization》2013,34(7-8):881-893
The boundedness and compactness of the generalized weighted composition operator on weighted Bergman spaces are discussed. 相似文献
108.
M.C. Rao 《Journal of Crystal Growth》2010,312(19):2799-2803
Thin films of LiCoO2 were prepared by pulsed laser deposition technique and the properties were studied in relation to the deposition parameters. The films deposited from a sintered composite target (LiCoO2+Li2O) in an oxygen partial pressure of 100 mTorr and at a substrate temperature of 300 °C exhibited preferred c-axis (0 0 3) orientation perpendicular to the substrate surface. The AFM data demonstrated that the films are composed of uniform distribution of fine grains with an average grain size of 80 nm. The grain size increased with an increase in substrate temperature. The (0 0 3) orientation decreased with increase in (1 0 4) orientation for the films deposited at higher substrate temperatures (>500 °C) indicating that the films’ growth is parallel to the substrate surface. The composition of the experimental films was analyzed using X-ray photoelectron spectroscopy (XPS). The binding energy peaks of Co(2p3/2) and Co(2p1/2) are, respectively, observed at 779.3 and 794.4 eV, which can be attributed to the Co3+ bonding state of LiCoO2. The electrochemical measurements were carried out on Li//LiCoO2 cells with a lithium metal foil as anode and LiCoO2 film as cathode of 1.5 cm2 active area using a Teflon home-made cell hardware. The Li//LiCoO2 cells were tested in the potential range 2.6-4.2 V. Specific capacity as high as 205 mC/cm2 μm was measured for the film grown at 700 °C. The growth of LiCoO2 films were studied in relation to the deposition parameters for their effective utilization as cathode materials in solid-state microbattery application. 相似文献
109.
<正>Acrylonitrile/N-[4-(aminosulfonyl)phenyl]acrylamide(AN/ASPAA) copolymers were synthesized and used as a host of lithium ion conducting electrolytes.The composition,molecular weight and molecular weight distribution of AN/ASPAA copolymers were determined,and the influence of copolymer composition on the glass temperature of AN/ASPAA copolymers and the ion conductivity of electrolytes were investigated.The molecular weights of AN/ASPAA copolymers were lower than those of AN and ASPAA homopolymers due to the cross-termination reaction.The glass temperatures of AN/ASPAA copolymers increased as the molar fraction of ASPAA units in copolymers increased.The lithium ion conductivities of the polymer electrolytes increased initially as the molar fraction of ASPAA units in copolymers increased,and a maximum conductivity was achieved when the molar fraction of ASPAA in the copolymer was 16.8%. 相似文献
110.
Thomas L. Kriete Barbara D. MacCluer Jennifer L. Moorhouse 《Journal of Functional Analysis》2009,257(8):2378-2409
We determine the essential spectra of algebraic combinations of Toeplitz operators with continuous symbol and composition operators induced by a class of linear-fractional non-automorphisms of the unit disk. The operators in question act on the Hardy space H2 on the unit disk. Our method is to realize the C*-algebra that they generate as an extension of the compact operators by a concrete C*-algebra whose invertible elements are easily characterized. 相似文献