The Interference of Magnetoelastic Waves in an Yttrium Iron Garnet Film

Physics of the Solid State - The interference of excited and received by current antennae magnetoelastic waves counterpropagating in an yttrium iron garnet film is experimentally studied. It is...     

Regenerative energy conversion using oxygen solid electrolytes

A heat machine is studied of regenerative type, based on solid electrolytes with unipolar oxygen conductivity. The achieved specific power is about 0.2 mW/cm². Electrical characteristics are derived as a function of temperature, pressure and gas composition in the working chamber of the converter. Factors which influence the specific power as well as optimal regimes for the functioning of the device are determined.     

Chloromethyl-, dichloromethyl-, and trichloromethyl-1,2,4-triazines and their 4-oxides: method for the synthesis and tele-substitution reactions with C-nucleophiles

A simple procedure was developed for the synthesis of 1,2,4-triazines and their 4-oxides containing the ClCH₂, Cl₂CH, or CCl₃ group at position 3 by cyclization of 2-aryl-2-hydrazono-1-oximinoethanes with the corresponding chloroacetonitriles. The reaction pathway depends on the number of halogen atoms in the acetonitrile used. The reactions with trichloroacetonitrile, monochloroacetonitrile, and dichloroacetonitrile afford 3-trichloromethyl-1,2,4-triazines, 3-chloromethyl-1,2,4-triazine 4-oxides, and a mixture of the corresponding dichloromethyltriazines and their 4-oxides, respectively. The reactions of 3-trichloromethyl-1,2,4-triazines with indoles and phenols are accompanied by tele-substitution with elimination of halogen from the trichloromethyl group to give 5-indolyl- (or 5-hydroxyphenyl)-3-dichloromethyl-1,2,4-triazines.     

On the mechanism of arylation of ethylene by palladium(II)

The phenylation of ethylene with benzene under the effect of palladium acetate at [C₂H₄] [Pd(OAc)₂] has been found to give styrene and trans-stilbene via parallel rather than consecutive reactions. The data obtained indicate that styrene and stilbene are formed through the same intermediate. The reaction mechanism is discussed.

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, [C₂H₄][Pd(OAc)₂] - . , . .

     

Alkylation of hydroquinone with isobutene catalyzed by heteropoly acids in a two-phase system

The liquid-phase C-alkylation of hidroquinone with isobutene catalyzed by heteropoly acids H₃PW₁₂O₄₀, H₆P₂W₁₈O₆₂ and H₆P₂W₂₁O₇₁ (HPA) under phase-transfer conditions in a two-phase system, including toluene (upper phase) and HPA dioxane etherate, HPA·xC₄H₈O₁₂·yH₂O, (lower phase) has been studied.     

Catalysis of the dealkylation of derivatives of 2,6-di-tert-butylphenol by heteropoly acids

Conclusions The tungsten heteropoly acids in acetic acid are the most active in the dealkylation of 4-alkyl-2,6-di-tert-butylphenols. The reaction is first order with respect to the substrate and with respect to the HPA, and water slows the reaction. It has been postulated that the dealkylation reaction is mediated mainly by the undissociated molecules of the HPA.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 752–756, April, 1987.     

Study of coherent diffractive production reactions ofp+C→[Y 0 K +]+C type and observation of narrow structures in ∑ (1385)0 K + and ∑0 K + effective mass spectra

In the experiments at the SPHINX facility in 70 GeV proton beam of the IHEP accelerator the coherent diffractive production reactions on carbon nucleip+C [(1385)⁰ K ⁺+C andp+C[⁰ K ⁺]+C were investigated. The evidences for new baryon states were obtained in the study of hyperon-kaon effective mass spectra in these two reactions:X (2050) with massM=(2052±6) MeV and width =(35 _–35 ⁺²² ) MeV inM[(1385)⁰ K ⁺] andX(2000) withM=1999±6 MeV and =91±17 MeV inM[⁰ K ⁺]. The unusual features of these massive states (small enough decay widths, anomalously large branching ratios for decays with strange particles emission) make them very serious candidates for cryptoexotic pentaquark baryons with hidden strangeness.     

Oxidation of pseudocumene in acetic acid

The oxidation of pseudocumene in the benzene nucleus can be effected in HOAc solution by using inorganic oxidizing agents containing oxygen, such as NaNO₃, hetero-polyacids, O₂, Na₂S₂O₈ and H₂O₂, with Pd(OAc)₂ as catalyst. Na₂S₂O₈ and H₂O₂ are the most effective, being also active in the absence of Pd(II).Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 9, pp. 2069–2073, September, 1989.The authors thank V. I. Zheivot, V. A. Bushmelev and K. F. Obzherinoi for their assistance in the investigation.