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1.
Joaquim Bruna 《Journal of Fourier Analysis and Applications》2006,12(1):71-82
We show that the discrete translation parameter sets Λ ⊂ ℝ for which some φ ∈ L1(ℝ) exists such that the translates φ(x − λ), λ ∈ Λ, span L1(ℝ) are exactly the uniqueness sets for certain quasianalytic classes, and give explicit constructions of such generators
φ. We also consider a similar situation for affine systems of the type φ(μx − λ), μ ∈ Γ, λ ∈ Λ. 相似文献
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Bruna Bovio 《Journal of organometallic chemistry》1983,252(1):71-82
Crystals of C24H36N6O6Cr2 are monoclinic, a 15.380(3), b 13.965(2), c 14.459(3) Å, β 92.18(1)°; Z = 4; space group P21 with two independent molecules in the asymmetric unit. The crystal structure was determined from X-ray diffractometer data by direct methods and refined by least-squares methods to R = 0.066 for 2430 independent observed reflections. It consists of discrete molecules, in which each Cr atom is surrounded by three cis carbonyl groups and three cis nitrogen atoms of three 3,3,4,4-tetramethyl-1,2-diazetine ligands, in a deformed octahedral coordination. There is no evidence of intramolecular Cr ? Cr interaction. 相似文献
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G. H. Lushington P. J. Bruna F. Grein 《Zeitschrift für Physik D Atoms, Molecules and Clusters》1996,36(3-4):301-309
Electron-spin magnetic moments, in the form ofg-shifts, have been computed at the ROHF level for theX 2∑+ states of LiH+, BeH2+, LiH?, BeH and BH+. A perturbative approach, complete to second-order in appropriate Breit-Pauli operators, has been used. Retention of two-centre integrals has proven vital. First-order terms are important, especially in describing the negativeg ∥ shifts observed experimentally in2∑+ molecules. The relativistic mass correction dominates in first-order, except for LiH? where the two-electron spin-Zeeman gauge correction supersedes. Second-order terms contribute negatively, and only to the Δg ⊥ component. Along the isoelectronic series LiH? → BeH → BH+, the magnitude of Δg ⊥ increases due to the dependence of spin-orbit coupling on nuclear charge. The relation ofg-shifts to electronic structure and bonding is explored. 相似文献
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Cavalcanti André D. D. Melo Bruna A. G. Oliveira Rhelvis C. Santana Maria H. A. 《Applied biochemistry and biotechnology》2019,188(2):527-539
Applied Biochemistry and Biotechnology - The effects of ethanol/broth proportions and the number of steps at varying pH in the presence or absence of sodium chloride (NaCl) were studied as... 相似文献
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Green solvent approach for printable large deformation thermoplastic elastomer based piezoresistive sensors and their suitability for biomedical applications
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Bruna F. Gonçalves Pedro Costa Juliana Oliveira Sylvie Ribeiro Vitor Correia Gabriela Botelho Senentxu Lanceros‐Mendez 《Journal of Polymer Science.Polymer Physics》2016,54(20):2092-2103
Composites based on biocompatible thermoplastic elastomer styrene‐ethylene/butylene‐styrene (SEBS) as matrix and multi‐walled carbon nanotubes (MWCNT) as nanofillers show excellent mechanical and piezoresistive properties from low to large deformations. The MWCNT/SEBS composites have been prepared following a green solvent approach, to extend their range of applicability to biomedical applications. The obtained composites with 2, 4, and 5 wt % MWCNT content provide suitable piezoresistive response up to 80% deformation with a piezoresistive sensibility near 2.7, depending on the applied strain and MWCNT content. Composite sensors were also developed by spray and screen printing and integrated with an electronic data acquisition system with RF communication. The possibility to accurately control the composites properties and performance by varying MWCNT content, viscosity, and mechanical properties of the polymer matrix, shows the large potential of the system for the development of large deformation printable piezoresistive sensors. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2016 , 54, 2092–2103 相似文献
10.
F. Enrichi R. Riccò P. Scopece A. Parma A. R. Mazaheri P. Riello A. Benedetti 《Journal of nanoparticle research》2010,12(5):1925-1931
In this study, we report the comparison between Eu3+-doped silica nanoparticles synthesized by Stöber method using Eu(NO3)3 or Eu(acac)3 as precursors. The impact of different europium species on the properties of the final silica nanospheres is investigated in details in terms of size, morphology, reachable doping amount, and luminescence efficiency. Moreover, the results obtained for different thermal treatments are presented and discussed. It is shown that the organic complex modify the silica growing process, leading to bigger and irregular nanoparticles (500–800 nm) with respect to the perfectly spherical ones (400 nm) obtained by the nitrate salt, but their luminescence intensity and lifetime is significantly higher when 800–900 °C annealing is performed. 相似文献