Kinetics of oxidative coupling of thiophene in the presence of Pd(OAc)2

The kinetics of oxidative coupling of thiophene to bithiophene in the presence of Pd(OAc)₂ in acetic acid solution has been studied at 60–80°C. The mechanism of the reaction is discussed.

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Pd (OAc)₂ HOAc 60–80°. .

     

On wide-band mirrors for soft X-ray range

The properties of smooth curved surfaces which can deflect the soft X-ray beams to large angles and reflect them effectively are considered. The wave sliding along the curved cylindrical surface has been analysed and the structure of the electromagnetic field has been found both in the medium and in vacuum. Large reflectivity has been predicted in wavelength regions 50 Å < λ < 150 Å and λ < 20 Å for several elements with known optical constants. In contrast to the multilayer structures which are widely used now, the curved mirrors provide a large reflectivity in a broad X-ray wavelength region.     

Reactivities of some carbonyl compounds of the furan series in catalytic hydrogenation

The rate of hydrogenation of some carbonyl compounds of the furan series on Raney nickel-titanium-aluminum and copper-chromium oxide catalysts decreased in proportion to the decrease in the frequency of the absorption band of the C=O bond.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 4, pp. 447–449, April, 1983.     

Model approach to solving the inverse problem of X-ray reflectometry and its application to the study of the internal structure of hafnium oxide films

The key features of the inverse problem of X-ray reflectometry (i.e., the reconstruction of the depth profile of the dielectric constant using an experimental angular dependence of reflectivity) are discussed and essential factors leading to the ambiguity of its solution are analyzed. A simple approach to studying the internal structure of HfO₂ films, which is based on the application of a physically reasonable model, is considered. The principles for constructing a film model and the criteria for choosing a minimal number of fitting parameters are discussed. It is shown that the ambiguity of the solution to the inverse problem is retained even for the simplest single-film models. Approaches allowing one to pick out the most realistic solution from several variants are discussed.     

Self-Action Effects in the Propagation of Surface Magnetostatic Wave Pulses in a Magnonic Crystal–Dielectric–Metal Structure

Technical Physics - We have analyzed the self-action effects in the propagation of surface magnetostatic wave (SMSW) pulses in a 1D magnonic crystal–dielectric–metal structure in which...