Strain Coupling of Conversion-type Fe3O4 Thin Films for Lithium Ion Batteries

Lithiation/delithiation induces significant stresses and strains into the electrodes for lithium ion batteries, which can severely degrade their cycling performance. Moreover, this electrochemically induced strain can interact with the local strain existing at solid–solid interfaces. It is not clear how this interaction affects the lithiation mechanism. The effect of this coupling on the lithiation kinetics in epitaxial Fe₃O₄ thin film on a Nb-doped SrTiO₃ substrate is investigated. In situ and ex situ transmission electron microscopy (TEM) results show that the lithiation is suppressed by the compressive interfacial strain. At the interface between the film and substrate, the existence of Li_xFe₃O₄ rock-salt phase during lithiation consequently restrains the film from delamination. 2D phase-field simulation verifies the effect of strain. This work provides critical insights of understanding the solid–solid interfaces of conversion-type electrodes.     

Adhesion of acrylate-based water dispersion to polypropylene hybrid fabrics

The increase in the content of crosslinking agent and surfactant in acrylate-based water dispersion results in an increase of surface parameters e.g. total SFE and its polar component, interfacial and mechanical work of adhesion of polyacrylate to PP hybrid fabrics. UV irradiation of polyacrylate coating in the course of accelerating ageing has the same effect on surface and adhesive properties as a crosslinking agent or surfactant and leads to a considerable growth of the total SFE, its polar component, interfacial and mechanical work of adhesion. The increase in the interfacial and mechanical work of adhesion with the increase of the crosslinking agent and/or surfactant content in acrylate-based water dispersion is higher for PES/PP fabrics compared to the PA/PP system. The adhesive properties of the film obtained from acrylate-based water dispersion are substantially influenced by the presence of a surfactant and a crosslinking agent.     

Computer modeling of in terferograms of flowing plasma and determination of the phase shift

Interferograms of the flowing gas contain information about the phase shift between the object and the reference beams. The determination of the phase shift is the first step in getting information about the inner distribution of the density in cylindrically symmetric discharges. Slightly modified Takeda method based on the Fourier transformation is applied to determine the phase information from the interferogram. The least squares spline approximation is used for approximation and smoothing intensity profiles. At the same time, cubic splines with their end-knots conditions naturally realize “hanning windows” eliminating unwanted edge effects. For the purpose of numerical testing of the method, we developed a code that for a density given in advance reconstructs the corresponding interferogram.     

Basis set convergence of indirect spin-spin coupling constants in the Kohn-Sham limit for several small molecules

The performance of more than 40 density functionals in predicting indirect spin-spin coupling constants (SSCCs) in the Kohn-Sham basis set limit was tested. For comparison, similar calculations were performed using the RHF, SOPPA, SOPPA(CC2), and SOPPA(CCSD) methods, and the results were estimated toward the complete basis set (CBS) limit. The SSCCs of nine small molecules (N(2), CO, CO(2), NH(3), CH(4), C(2)H(2), C(2)H(4), C(2)H(6), and C(6)H(6)) were calculated using the dedicated Jensen pcJ-n polarization-consistent basis sets and used for the CBS limit estimations within the Kohn-Sham limit. These CBS results were compared with calculations using the aug-cc-pVTZ-J basis set. Among the 41 studied DFT methods, the tHCTHhyb, HSEh1PBE, HSE2PBE, wB97XD, wB97, and wB97X functionals reproduced accurately the experimental (1)J(XH) SSCCs and (3)J(HH60) and (2)J(HH(gem)) in ethane. Similarly, the functionals HSEh1PBE, HSE2PBE, wB97XD, wB97, and wB97X predicted accurately (1)J(CC), and B98, B97-1, B97-2, PBE1PBE, B1LYP, and O3LYP provided accurate (1)J(CO) results in the CO molecule. A very good performance for the calculation of the SSCCs based on the use of the relatively small basis set aug-cc-pVTZ-J was observed.     

Step-flow kinetics in nanowire growth

Nanowire growth occurs by step flow at the wire-catalyst interface, with strikingly different step-flow kinetics for solid versus liquid catalysts. Here we report quantitative in?situ measurements of step flow together with a kinetic model that reproduces the behavior. This allows us to identify the key parameters controlling step-flow growth, evaluate changes in the catalyst composition during growth, and identify the most favorable conditions for growing abrupt heterojunctions in nanowires.     

Synthesis of Azilsartan and Its Selected Potential Impurities

Synthesis of angiotensin II AT₁ receptor antagonist azilsartan is described. The results include reinvestigation of the described process as well as its novel modification. This new process includes transformation of the CN group into amidoxime moiety by aqueous hydroxylamine, its treatment with alkyl chloroformates and a base‐initiated cyclization of the formed (alkoxycarbonyl‐oxy)carbamimidoyl intermediates. Several so far undescribed side‐products were identified and some of them were synthesized and duly characterized as potential impurities.     

Randsingularität Laplacescher Transformierten

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