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71.
Antonio Di Domenico Andreas Gabriel Beatrix C. Hiesmayr Florian Hipp Marcus Huber Gerd Krizek Karoline Mühlbacher Sasa Radic Christoph Spengler Lukas Theussl 《Foundations of Physics》2012,42(6):778-802
An effective formalism is developed to handle decaying two-state systems. Herewith, observables of such systems can be described
by a single operator in the Heisenberg picture. This allows for using the usual framework in quantum information theory and,
hence, to enlighten the quantum features of such systems compared to non-decaying systems. We apply it to systems in high
energy physics, i.e. to oscillating meson–antimeson systems. In particular, we discuss the entropic Heisenberg uncertainty
relation for observables measured at different times at accelerator facilities including the effect of CP\mathcal{CP} violation, i.e. the imbalance of matter and antimatter. An operator-form of Bell inequalities for systems in high energy
physics is presented, i.e. a Bell-witness operator, which allows for simple analysis of unstable systems. 相似文献
72.
Substituted bipyridines were efficiently prepared by direct coupling between pyridine N-oxides and halopyridines using a palladium catalyst. Pyridine N-oxides with electron-withdrawing substituents gave the best yields. This method allows the convenient preparation of 2,2'-, 2,3'-, and 2,4'-bipyridines which are useful as functionalized ligands for metal complexes or as building blocks for supramolecular architectures. 相似文献
73.
74.
Teruhisa S. Komatsu Naoko Nakagawa Shin-ichi Sasa Hal Tasaki 《Journal of statistical physics》2011,142(1):127-153
Among various possible routes to extend entropy and thermodynamics to nonequilibrium steady states (NESS), we take the one
which is guided by operational thermodynamics and the Clausius relation. In our previous study, we derived the extended Clausius
relation for NESS, where the heat in the original relation is replaced by its “renormalized” counterpart called the excess
heat, and the Gibbs-Shannon expression for the entropy by a new symmetrized Gibbs-Shannon-like expression. Here we concentrate
on Markov processes describing heat conducting systems, and develop a new method for deriving thermodynamic relations. We
first present a new simpler derivation of the extended Clausius relation, and clarify its close relation with the linear response
theory. We then derive a new improved extended Clausius relation with a “nonlinear nonequilibrium” contribution which is written
as a correlation between work and heat. We argue that the “nonlinear nonequilibrium” contribution is unavoidable, and is determined
uniquely once we accept the (very natural) definition of the excess heat. Moreover it turns out that to operationally determine
the difference in the nonequilibrium entropy to the second order in the temperature difference, one may only use the previous
Clausius relation without a nonlinear term or must use the new relation, depending on the operation (i.e., the path in the
parameter space). This peculiar “twist” may be a clue to a better understanding of thermodynamics and statistical mechanics
of NESS. 相似文献
75.
Dr. Sasa Gu Dr. Sebastian Risse Prof. Dr. Yan Lu Prof. Dr. Matthias Ballauff 《Chemphyschem》2020,21(5):450-458
Experimental and kinetic modelling studies are presented to investigate the mechanism of 3,3′,5,5′-tetramethylbenzidine (TMB) oxidation by hydrogen peroxide (H2O2) catalyzed by peroxidase-like Pt nanoparticles immobilized in spherical polyelectrolyte brushes (SPB−Pt). Due to the high stability of SPB−Pt colloidal, this reaction can be monitored precisely in situ by UV/VIS spectroscopy. The time-dependent concentration of the blue-colored oxidation product of TMB expressed by different kinetic models was used to simulate the experimental data by a genetic fitting algorithm. After falsifying the models with abundant experimental data, it is found that both H2O2 and TMB adsorb on the surface of Pt nanoparticles to react, indicating that the reaction follows the Langmuir–Hinshelwood mechanism. A true rate constant k, characterizing the rate-determining step of the reaction and which is independent on the amount of catalysts used, is obtained for the first time. Furthermore, it is found that the product adsorbes strongly on the surface of nanoparticles, thus inhibiting the reaction. The entire analysis provides a new perspective to study the catalytic mechanism and evaluate the catalytic activity of the peroxidase-like nanoparticles. 相似文献
76.
Electrical resistivity of (SN)x crystal along the b-axis increases in Na ion solution by several times in a few tens of minutes. Temperature dependence of resistivity and transverse magnetoresistance at 4.2 K in Na-doped (SN)x do not change remarkably from the pristine (SN)x. These experimental results are discussed in terms of electron transfer from the dopant (Na) to (SN)x into consideration, comparing with the case of halogen doping. 相似文献
77.
J. Li K. I. Kolokolov C. Z. Ning D. C. Larrabee G. A. Khodaparast J. Kono K. Ueda Y. Nakajima S. Sasa M. Inoue 《Physica E: Low-dimensional Systems and Nanostructures》2004,20(3-4):268
Linear absorption spectra from intersubband resonance in InAs/AlSb quantum wells are analyzed theoretically using the intersubband semiconductor Bloch equation approach. Our model goes beyond the Hartree–Fock approximation and treats particle–particle correlations under the second Born approximation. Electron–electron and longitudinal optical phonon scatterings from such a treatment describe intrinsic line broadening to the intersubband resonance. Electron subbands are determined self-consistently with a spurious-state-free 8-band k·p Hamiltonian under the envelope function approximation. To compare with experimental measurements, we also included line broadening due to electron-interface roughness scattering. Excellent agreement was achieved for temperature-dependent absorption spectra in the mid-infrared frequency range, after taking into careful account the interplay of material parameters, nonparabolicity in bandstructure, and many-body effects. 相似文献
78.
Gonsior M Antonijevic S Krossing I 《Chemistry (Weinheim an der Bergstrasse, Germany)》2006,12(7):1997-2008
The first solid-state structures of complexed P3N3X6 (X = halogen) are reported for X = Cl. The compounds were obtained from P3N3Cl6 and Ag[Al(OR)4] salts in CH2Cl2/CS2 solution. The very weakly coordinating anion with R = C(CF3)3 led to the salt Ag(P3N3Cl6)2+[Al(OR)4]- (1), but the more strongly coordinating anion with R' = C(CH3)(CF3)2 gave the molecular adduct (P3N3Cl6)AgAl(OR')4 (3). Crystals of [Ag(CH2Cl2)(P3N3Cl6)2]+[Al(OR)4]- (2), in which Ag+ is coordinated by two phosphazene and one CH2Cl2 ligands, were isolated from CH2Cl2 solution. The three compounds were characterized by their X-ray structures, and 1 and 3 also by NMR and vibrational spectroscopy. Solution and solid-state 31P NMR investigations in combination with quantum chemically calculated chemical shifts show that the 31P NMR shifts of free and silver-coordinated P3N3Cl6 differ by less than 3 ppm and indicate a very weakly bound P3N3Cl6 ligand in 1. The experimental silver ion affinity (SIA) of the phosphazene ligand was derived from the solid-state structure of 3. The SIA shows that (PNCl2)3 is only a slightly stronger Lewis base than P4 and CH2Cl2, while other ligands such as S8, P4S3, toluene, and 1,2-Cl2C2H4 are far stronger ligands towards the silver cation. The energetics of the complexes were assessed with inclusion of entropic, thermal, and solvation contributions (MP2/TZVPP, COSMO). The formation of the cations in 1, 2, and 3 was calculated to be exergonic by delta(r)G(degrees)(CH2Cl2) = -97, -107, and -27 kJ mol(-1), respectively. All prepared complexes are thermally stable; formation of P3N3Cl5+ and AgCl was not observed, even at 60 degrees C in an ultrasonic bath. Therefore, the formation of P3N3Cl5+ was investigated by quantum chemical calculations. Other possible reaction pathways that could lead to the successful preparation of P3N3X5+ salts were defined. 相似文献
79.
诺氟沙星-锰络合体系的单扫描极谱法研究 总被引:5,自引:0,他引:5
采用单扫描极谱法研究了金属锰与诺氟沙星形成络合物的条件及反应机理。在pH 9.2 0NH3 NH4Cl缓冲体系中 ,诺氟沙星与锰络合并在 - 1.85V(vs.SCE)处产生一个灵敏的还原波 ,其峰高与NFX浓度在 8.0× 10 -6~ 1.9× 10 -5mol/L范围内呈现良好的线性关系 ,r =0 .995 4 ;检出限为 4 .0× 10 -6mol/L ;测得锰与诺氟沙星的配位比为 1∶2 ,表观稳定常数为 6 .37× 10 12 。 相似文献
80.
The motivation behind mathematically modeling the human operator is to help explain the response characteristics of the complex
dynamical system including the human manual controller. In this paper, we present two different fuzzy logic strategies for
human operator and sport modeling: fixed fuzzy-logic inference control and adaptive fuzzy-logic control, including neuro-fuzzy-fractal
control. As an application of the presented fuzzy strategies, we present a fuzzy-control based tennis simulator. 相似文献