1-Phenacylmethyl-2-(acylaminothiocarbonylamino)pyridinium bromides as protectors of steel acid corrosion

Inhibiting effect of 1-phenacylmethylpyridinium bromides containing acylthiourea substituents in the pyridine ring on corrosion of mild steel in sulfuric acid (3 M) was studied.     

Vibrational spectroscopy and study of the state and properties of catalysts

Conclusions It can be seen from the list of publications that the method of vibrational spectroscopy has a very broad application in catalysis. A distinctive characteristic of the present situation in this field is the transition to quantitative characterization of the properties of heterogeneous catalysts and to a wider use of theoretical calculations of normal vibrations in very diverse problems, and to a classifying by these means the properties of the substances studied. In the very near future, we can expect a considerable intensification of these trends, and development of more precise methods for the investigation of the properties of surface of solid bodies based on Raman spectroscopy.Institute of Catalysis, Siberian Branch, Academy of Sciences of the USSR. Translated from Zhurnal Strukturnoi Khimii, Vol. 28, No. 3, pp. 133–144, May–June, 1987.     

Asymptotic expansion in the central limit theorem for quadratic forms

We consider statistics of the form

Interaction between superconducting vortices and a Bloch wall in ferrite garnet films

A theoretical model for how Bloch walls occurring in in-plane magnetized ferrite garnet films can serve as efficient magnetic micromanipulators is presented. As an example, the walls' interaction with Abrikosov vortices in a superconductor in close contact with a garnet film is analyzed within the London approximation. The model explains how vortices are attracted to such walls, and excellent quantitative agreement is obtained for the resulting peaked flux profile determined experimentally in NbSe(2) using high-resolution magneto-optical imaging of vortices. In particular, this model, when generalized to include charged magnetic walls, explains the counterintuitive attraction observed between vortices and a Bloch wall of opposite polarity.     

Structural properties of star-shaped polyions: Entropic sampling

The method of entropic sampling within the Wang–Landau algorithm (a modern variant of the Monte Carlo method) is used to determine the densities of energy states of a strongly charged star-shaped polyelectrolyte within the framework of the lattice model. The equilibrium thermal and structural properties of the polyelectrolyte with the number of arms f ≤ 6 and the length of arms N _arm ≤ 73 in a wide temperature range are determined from the density of states. Such characteristics as the free energy, the mean-squared radius of gyration, its components, and the parameters characterizing the shape of a polyion are calculated. It is found that the concentration, length, and number of arms affect the thermal and structural properties. The main attention is focused on the effect of temperature on these properties. The coil-to-globule transition is detected, while for the polyion with the highest length of arms (N _arm = 24) the transition from the liquid globule to the crystal-like one is observed. Differences in the properties of the star-shaped and corresponding linear polyions are characterized.     

4-Methoxy-3-methylgoniothalamin from marine-derived fungi of the genus Penicillium

The new styrylpyrone derivative, viz. 4-methoxy-3-methylgoniothalamin (1), and the known compound sulochrin were isolated from the marine-derived fungi Penicillium glabrum and P. implicatum. The structure of compound 1 was determined by X-ray diffraction, 2D NMR spectroscopy, and high-resolution mass spectrometry. It was shown for the first time that sulochrin increases expression of the protein Hsp70.     

Modification of the MgO–Al2O3–TiO2–SiO2 Glass by Silver Diffusion for the Formation of Luminescent Molecular Clusters

Doklady Chemistry - The capabilities of diffusion treatment of alkali-free MgO–Al2O3–TiO2–SiO2 glass using Ag-containing salt melts or special pastes for the formation of...