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Pawel Uznanski Agnieszka Walkiewicz-Pietrzykowska Krzysztof Jankowski Joanna Zakrzewska Aleksander M. Wrobel Jacek Balcerzak Jacek Tyczkowski 《应用有机金属化学》2020,34(8):e5674
Amorphous silicon oxycarbide (a-SiOC:H) films produced by remote plasma RPCVD from diethoxymethylsilane (DEMS) were characterized in terms of their basic properties related to the coatings deposited using conventional plasma enhanced PECVD method. The effect of substrate temperature (TS) on the growth rate, chemical composition, structure, and properties of resulting a-SiOC:H films is reported. Film growth is an adsorption-controlled process, wherein two mechanisms can be distinguished with a transition at about TS=70°C. Depending on the temperature, films of different nature can be obtained, from polymer-like to highly crosslinked material with C-Si-O network. The chemical structure of a-SiOC:H films was characterized by FTIR, 13C and 29Si solid-state NMR, and X-ray photoelectron spectroscopes. The a-SiOC:H films were also characterized in terms of their density, refractive index, surface morphology, conformality of coverage, hardness, adhesion to a substrate, and friction coefficient. The films were found to be morphologically homogeneous materials exhibiting good conformality of coverage and small surface roughness. Their refractive index exhibits anomalous effect revealing a minimum value at TS=125°C. Due to their exceptional physical properties a-SiOC:H films produced by RPCVD from DEMS precursor seems to be useful as potential dielectric materials or coatings for various encapsulation applications. 相似文献
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A cluster density matrix is proposed for calculation of the thermodynamic averages in the effective field theory with correlations. On this basis, derivation of the Gibbs free-energy for the Honmura–Kaneyoshi method is made. 相似文献
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Nonlinear Dynamics - Classical method of Lyapunov exponents spectrum estimation for a n-th-order continuous-time, smooth dynamical system involves Gram–Schmidt orthonormalization and... 相似文献
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We extend a new method to measure possible variation of the speed of light by using Baryon Acoustic Oscillations and the Hubble function onto an inhomogeneous pressure model of the universe. The method relies on the fact that there is a simple relation between the angular diameter distance maximum and the Hubble function (H) evaluated at the same maximum‐condition redshift, which includes the speed of light c. One limit of such a method was the assumption of the vanishing of spatial curvature (though, as it has been shown, a non‐zero curvature has negligible effect). In this paper, apart from taking into account an inhomogeneity, we consider non‐zero spatial curvature and calculate an exact relation between and H. Our main result is the evaluation if current or future missions such as Square Kilometer Array (SKA) can be sensitive enough to detect any spatial variation of c which can in principle be related to the recently observed spatial variation of the fine structure constant (an effect known as α‐dipole). 相似文献
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A sensitive extraction-spectrophotometric method of the determination of osmium, taking advantage of the ion-associate of the chloride osmium anion with brilliant green has been developed. The complex is extracted from aqueous phase with a mixture of C6H5Cl + CCl4 (3 + 1). Molar absorptivity () at 640 nm is 1.95 × 105 liters mol−1cm−1 (specific ABSORPTIVITY = 1.03). The relative standard deviation is 1–3%. The mole ratio of Os:BG in the complex is 1:3. Platinum metals interfere with the determination of osmium. The determination can be highly selective after preliminary separation of osmium by distillation as OsO4. 相似文献
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Platinum and ruthenium in carbon supported Pt and Pt-Ru catalysts were determined by direct and derivative spectrophotometric methods. Complexes of platinum and ruthenium with SnCl(3)(-) ligands (tin(II) chloride in HCl) were used to determine both metals in solutions obtained after digestion of the samples of the catalysts. Platinum in the Pt/C catalyst can be determined in solutions obtained by digestion of the samples in aqua regia. Derivative spectrophotometry was used to determine both metals in the presence of each other in solutions obtained after digestion of samples of the Pt-Ru/C catalyst in the mixture of HCl+HNO(3) (6:1). The first derivative at 377 nm (;zero-crossing' point of ruthenium) and the second-derivative values at 495 nm (;zero-crossing' point of platinum) were used to estimate the concentration of platinum and ruthenium, respectively. 相似文献