Hydrogenation of acetone on technetium catalysts

The catalytic properties of supported mono- and bimetallic catalysts of the Tc/support, M/support, and M-Tc/support types (M=Pt, Pd, Rh, Ru, Ni, Re, Co; supports are γ-Al₂O₃, MgO, SiO₂) were investigated in the acetone hydrogenation. The main products of this reaction are isopropyl alcohol and propane. The catalytic activity in the acetone hydrogenation of the metals studied decreases in the consequence Pt>Tc≈Rh>Pd>Ru >Ni≈Re>Co (with γ-Al₂O₃ as the support). The influence of support nature on the catalytic activity was investigated for the Rh−Tc system as an example. A nonadditive increase in the catalytic activity of Rh−Tc/γ-Al₂O₃ in comparison with monometallic catalysts was found. The state of the surface of the catalysts was characterized by the UV-VIS diffuse reflectance spectra. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 3, pp. 414–417, March, 1998.     

Radiolytic Gas Formation in Dilute Oxalic Acid Aqueous Solutions

The radiolytic gas formation in aqueous oxalic acid solutions was studied. The concentrations of ₂ and ₂, the gas phase constituents, were measured. It was found that gas evolution is mainly due to the degradation of both oxalic acid and its radiolysis products.     

An NMR study of comenic acid and its salts with Li<Superscript>+</Superscript> and Na<Superscript>+</Superscript> in aqueous solution and solid state

The forms and structure of comenic acid and its salts with Na⁺ and Li⁺ in solution and solid state are studied by multinuclear NMR spectroscopy. The formation of dimeric structures of comenic acid in the solid state is shown. It is found that disubstituted sodium and lithium salts have different structures.     

Catalytic properties of chromites with a spinel structure in the oxidation of CO and hydrocarbons and reduction of nitrogen oxides

The catalytic activity of supported chromites MCr₂O₄/-Al₂O₃ (M = Cu, Co, Mn, Zn, Mg) in the oxidation of CO, C₃H₆, and o-xylene and NO_x reduction was studied. The catalytic activity depends on the calcination temperature and cation nature. The features of the formation of the catalysts were studied by the UV-Vis diffuse reflectance and IR spectroscopies.     

Antibody immobilisation on the metal and silicon surfaces. The use of self-assembled layers and specific receptors

The use of Staphylococcal protein A and lectins as intermediate immobilising agents allows operators to orient antibodies (Ab) towards the solution due to the presence of a specific binding sites of immunoglobulin (Ig) molecules. Antibodies of different species of animals have unequal affinities to individual lectins. The effective thickness of immobilised Ab's depends on the type of substrates used and increases in the following sequence: bare gold or silicon surface, the surface treated with self-assembled polyelectrolytes (PESA) or with protein A or some lectins deposited on the preliminary formed polyelectrolyte layer. The glycolysated protein of jp51 may be selectively immobilised from the mixture of retroviral proteins (p24 and jp51), if it is necessary to distinguish infected animals from preliminarily immunised ones by means of a vaccine based on p24 protein. It was shown that the use of Staphylococcal protein A, instead of some lectins as intermediate layer for the Ab immobilisation, does not lead to a more sensitive determination of such low-weight toxins as 2,4-dichlorophenoxyacetic acid (2,4-D). The above-mentioned results were obtained with surface plasmon resonance (SPR) technique.     

Hydrogenation of carbon monoxide over technetium catalysts

Supported Tc catalysts are active in CO hydrogenation, their activity depending on the nature of the support. The reaction proceeds predominantly toward methane formation. All catalysts studied yielded very little C₂ and C₃ hydrocarbons. The thermal desorption data indicate that the CO strongly bound to the substrate is responsible for CH₄ formation.Institute of Physical Chemistry, Russian Academy of Sciences, 117915 Moscow. Translated from Izvestiya Akademii Nauk, Seriya Khimicheskaya, No. 7, pp. 1507–1511, July, 1992.