Influence of a pulsed magnetic field on the silver halide photographic process

Imaging in Russian and foreign silver halide photographic materials exposed to light or a gas discharge under the influence of a pulsed magnetic field is studied. It is shown that a single 0.12-s-long 4.2 kOe pulse of the magnetic field (magnetic pulse) synchronized with a light flash considerably improves the photosensitivity of the materials, while not influencing it in the absence of the flash. The pre-exposure of the asprepared photomaterials and the materials after 8-year aging to a series of 250 magnetic pulses with the above parameters deteriorates the gas-discharge sensitivity of the former and raises the sensitivity of the latter.     

High-Speed Composite Microactuator Based on Ti<Subscript>2</Subscript>NiCu Alloy with Shape Memory Effect

Samples of microactuators are made of a bimorph composite of Ti₂NiCu alloy with a thermoelastic martensitic transition and the shape memory effect, and their response rate is investigated. The active layer of the composite actuator is a layer of the rapidly quenched Ti₂NiCu alloy, pseudoplastically prestretched, and an amorphous layer of the same alloy is used as an elastic layer. Typical sizes of the microactuator are 30 × 2 × 2 μm. The controlled amplitude of the displacement of the microactuator tip is approximately 1 μm. The response rate of the microactuator was investigated by scanning electron microscopy. Activation of the microactuator was achieved by heating when electric pulses were passed through it. Full activation of the microactuator at frequencies up to 1 kHz was demonstrated; partial activation was observed at frequencies up to 8 kHz. The possibility of operating the device in a self-oscillating mode at frequencies of the order of 100 kHz is demonstrated.     

Axially Symmetric Solution of the Weyl–Cartan Theory of Gravity and the Problem of the Rotation Curves of Galaxies

Russian Physics Journal -     

Glycation sites of human plasma proteins are affected to different extents by hyperglycemic conditions in type 2 diabetes mellitus

Glucose can modify proteins in human blood, forming early glycation products (e.g., Amadori compounds), which can slowly degrade to advanced glycation endproducts (AGEs). AGEs contribute significantly to complications of diabetes mellitus and, thus, represent markers of advanced disease stages. They are, however, currently unsuitable for early diagnosis and therapeutic monitoring. Here, we report sensitive strategies to identify and relatively quantify protein glycation sites in human plasma samples obtained from type 2 diabetes mellitus (T2DM) patients and age-matched nondiabetic individuals using a bottom-up approach. Specifically, Amadori peptides were enriched from tryptic digests by boronic acid affinity chromatography, separated by reversed-phase chromatography, and analyzed on-line by high-resolution mass spectrometry. Among the 52 Amadori peptides studied here were 20 peptides resembling 19 glycation sites in six human proteins detected at statistically significantly higher levels in T2DM than in the normoglycemic controls. Four positions appeared to be unique for T2DM within the detection limit. All 19 glycation sites represent promising new biomarker candidates for early diagnosis of T2DM and adequate therapeutic control, as they may indicate early metabolic changes preceding T2DM. Graphical Abstract

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The Use of Galvanic Displacement for Synthesizing Pt/Carbide (Mo2C,ZrC, NbC) Catalysts Highly Active in the Hydrogen Evolution Reaction

Russian Journal of Electrochemistry - The composite materials involving platinum nanoparticles on the surface of carbides of Mo, Zr, and Nb are synthesized by the currentless redox reaction between...     

Detailed kinetic mechanism of the multistep oxidation and combustion of isopentane and isohexane

A detailed kinetic mechanism was developed for the oxidation and combustion of isopentane (2-methylbutane) and isohexane (2-methylpentane), which describes both high-temperature reactions and a multistep process in the region of low temperatures. These hydrocarbons were chosen because they, together with isobutane, are the first members in the homologous series of isomerized alkanes and a higher member of this series—isooctane (2,2,4-trimethylpentane)—exhibited multistep self-ignition in experiments; in this case, the above isomers can be important intermediate products. The process of the multistep self-ignition of the above hydrocarbons under specific conditions occurs in three sequential steps (in the form of cold and blue flames and hot explosion) characteristic of normal alkanes. The calculations of self-ignition and flame propagation were performed by the developed mechanism; the results of the calculations were compared with the experimental data and their satisfactory qualitative and quantitative agreement was obtained.     

Thermal and structural characterization of bitumen by modulated differential scanning calorimetry

Journal of Thermal Analysis and Calorimetry - This paper presents the results of investigation of model bitumens, prepared by mixing of individual fractions of bitumen (saturates, aromatics, waxes,...