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561.
We study the typical behavior of bounded linear operators on infinite-dimensional complex separable Hilbert spaces in the norm, strong-star, strong, weak polynomial and weak topologies. In particular, we investigate typical spectral properties, the problem of unitary equivalence of typical operators, and their embeddability into C 0-semigroups. Our results provide information on the applicability of Baire category methods in the theory of Hilbert space operators. 相似文献
562.
563.
Thomas Gutsche Tanja Branz Amand Faessler Ian Woo Lee Valery E. Lyubovitskij 《中国物理 C》2010,34(9):1185-1190
We discuss a possible interpretation of the open charm mesons D＊s0 （2317）,D s1 （2460） and the hidden charm mesons X（3872）,Y（3940） and Y（4140） as hadron molecules.Using a phenomenological Lagrangian approach we review the strong and radiative decays of the D＊ s0 （2317） and D s1 （2460） states.The X（3872） is assumed to consist dominantly of molecular hadronic components with an additional small admixture of a charmonium configuration.Determing the radiative （γJ/ψ and γψ（2s）） and strong （J/ψ2π and J/ψ3π） decay modes we show that the present experimental observation is consistent with the molecular structure assumption of the X（3872）.Finally,we give evidence for molecular interpretations of the Y（3940） and Y（4140） related to the observed strong decay modes J/ψ＋ω or J/ψ＋φ,respectively. 相似文献
564.
U. Winkler D. Eich Z. H. Chen R. Fink S. K. Kulkarni E. Umbach 《physica status solidi (a)》1999,173(1):253-259
The thermal behaviour of CdS nanoparticles and especially of their surfaces has been investigated by high resolution photoelectron spectroscopy. Different annealing characteristics were observed for particles of different sizes. From the changes of surface core-level shifts in the S 2p and Cd 3d5/2 spectra we derive that the nanoparticle surface, which is S-terminated at room temperature, changes after annealing by removal of S atoms and segregation of Cd atoms. Furthermore, we observe that the temperature at which this process takes place depends on the particle size. 相似文献
565.
Tanja Pečnik;Andreja Eršte;Aleksander Matavž;Vid Bobnar;Maksim Ivanov;Juras Banys;Feng Xiang;Hong Wang;Barbara Malič;Sebastjan Glinšek 《Europhysics letters》2016,114(4)
Polycrystalline Ba0.5Sr0.5TiO3 films, with thicknesses between 90 and 600 nm, were prepared on alumina substrates at 900 °C by chemical solution deposition (CSD) and a dielectric spectroscopy investigation of the in-plane properties was performed. The 5-kHz permittivity ε ′ shows a non-monotonic thickness dependence, reaching 1230 at room temperature for the 310-nm-thick film, whose grain size is ∼75 nm. Its 15-GHz-value and losses are 1105 and 0.05, respectively. The temperature of the permittivity maximum T max at 5 kHz decreases with increasing thickness from 277 to 250 K for the 170- and 600-nm-thick films, respectively, which has been linked to the residual biaxial stress. A hysteresis is observed in the permittivity ε ′-electric field E DC characteristics in all the films up to ∼50 K above T max . Frequency dispersion in which permittivity decreases with increasing frequency is present below T max in films thicker than 90 nm. The high permittivity values of the thinnest films, which are among the highest reported in the (Ba,Sr)TiO3 films with grain sizes below 75 nm, are a direct proof of the optimized CSD processing conditions.https://doi.org/10.1209/0295-5075/114/47009 相似文献
566.
The underdamped,non-linear,generalized Langevin equation is widely used to model coarse-grained dynamics of soft and biological materials. By means of a projection operator formalism,we show under which approximations this equation can be obtained from the dynamics of the underlying microscopic system and in which cases it makes sense to introduce a potential of mean force. We discuss shortcomings of previous derivations presented in the literature and demonstrate the implications of our derivation for the structure of memory terms and for generalized fluctuation-dissipation relations. We show,in particular,that the widely used,simple structure which contains a potential of mean force,a memory term which is linear in the observable,and a fluctuating force which is related to the memory term by a fluctuation-dissipation relation,is neither exact nor can it,in general,be derived as a controlled approximation to the exact dynamics.https://doi.org/10.1209/0295-5075/ac35ba 相似文献
567.
Tanja S. Lehmann;Rainer Niewa; 《欧洲无机化学杂志》2019,2019(5):730-734
Two iron nitrides γ-FeN0.13 and ε-Fe3N1.51 were synthesized electrochemically in a molten salt system KCl–LiCl at 450 °C. For the electrochemical formation of γ-FeN0.13, which crystallizes in Fm3m with a = 367.46(7) pm, either Li3N or KNO3 can be added to the salt mixture as nitrogen source. An addition of Li3N corresponds to anodic polarization (anodic electrolysis) of the working electrode and KNO3 to cathodic polarization (cathodic electrolysis). The chosen applied voltages were 0.8 V and 1.4 V, respectively. Electrochemical synthesis employing a pure α-iron foil as working electrode results in thicker layers than using an iron rod, independent of the polarization of the working electrodes. Cathodic electrolysis delivers a higher layer thickness compared to anodic electrolysis. Anodic electrolysis of a pure α-iron foil at 2.2 V and a duration of 3 h provides ε-Fe3N1.51 as bulk material. Structural refinements by the Rietveld method result in a hexagonal unit cell with parameters of a = 478.06(3) pm and c = 441.82(3) pm indicating the high nitrogen content in agreement with an elemental analysis. 相似文献
568.
Tanja S. Lehmann;Björn Blaschkowski;Rainer Niewa; 《欧洲无机化学杂志》2019,2019(13):1708-1708
Invited for the cover of this issue is the group of Rainer Niewa from Universität Stuttgart, Germany. The cover image shows the formation and movement of nitride ions within a salt, initiated by an electric current. 相似文献
569.
570.
Majda Kolenović Serezlić;Rušid Hasić;Darko Ašanin;Biljana Šmit;Sanja Lj. Matić;Marina Ćendić Serafinović;Danijela Nikodijević;Jovana Jovankić;Sanja Grgurić-Šipka;Tanja V. Soldatović; 《应用有机金属化学》2024,38(4):e7413
The synthesis and characterization of novel hetrometallic complexes [{cis-PtCl(NH3)2(μ-4,4′-bipyridyl)ZnCl(terpy-Cl)}](ClO4)2 (C1a), [{trans-PtCl(NH3)2(μ-4,4′-bipyridyl)ZnCl(terpy)}](ClO4)2 (C2a), [{cis-PtCl(NH3)2(μ-pyrazine)ZnCl(terpy-Cl)}](ClO4)2 (C3a) and [{trans-PtCl(NH3)2(μ-pyrazine)ZnCl(terpy-Cl)}](ClO4)2 (C4a) (where terpy-Cl = 4′-chloro-2,2′:6′,2′′-terpyridine) was done. Acid–base titrations were performed by UV–Vis spectrophotometric method to evaluate the pKa values of corresponding aqua complexes. Interactions between complexes and important biomolecules, guanosine-5′-monophosphate (5′-GMP) and glutathione (GSH) were examined by 1H NMR spectroscopy. The chloride substituent at the 4′ position on the middle pyridine ring of terpyridine ligand significantly affects the coordination of biomolecules, as well as overall stability of complexes. The complexes were evaluated in vitro for the antioxidant prevention of DNA damages. All tested novel complexes demonstrated a significant reduction in DNA damage against oxidative modifications of DNA caused by the hydroxyl and peroxyl radicals. Also, cytotoxicity evaluation showed that significant cytotoxicity occurs only after long-term effect of C1a, C2a and C3a, complexes in HCT-116 cells. Molecular docking studies predict results in agreement with experimental research. 相似文献