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The mechanism of acylamination of arenes with nitroalkanes in polyphosphoric acid has been clarified. The influence of the concentration of polyphosphoric acid, the structure of the starting compounds, and temperature on the result of the Beckmann rearrangement, which makes it possible to shift the reaction towards either benzamides or anilides, has been assessed. [ABSTRACT FROM AUTHOR]

We studied the effect of pluronics P85, L61, and F68 with different hydrophilic-lipophilic characteristics on association of LDL. It was found that pluronics with pronounced hydrophobic properties (P85 and L61) in concentrations close to or surpassing the critical concentration of micelle formation inhibited LDL association, while hydrophilic pluronic F68 in all concentrations had no effect on LDL association. [ABSTRACT FROM AUTHOR]

This article is devoted to the development of recommendations for the selection of inertial and stiffness parameters of an inspection pig for oil and gas pipelines to reduce its vibrations when moving through the pipe. [ABSTRACT FROM AUTHOR]

Self-oscillations of an intra-pipe inspection pig are investigated. A dynamic model of the machine is formulated, and its motion regimes are analyzed qualitatively. The law governing the motion of the inspection pig and the law governing the velocity variation corresponding to it are derived. [ABSTRACT FROM AUTHOR]

The problems of cleaning pipe interior are reviewed. The main problem is jamming of the cleaning scraper, which may cause complete blocking of the pipe. The causes of occurrence of this problem and the means of its prevention are described. The salient merits and demerits of new designs for pipe cleaning currently being developed both abroad and in our country are evaluated. [ABSTRACT FROM AUTHOR]

The relative energies of possible phases in a Ti–C system in the hcp-lattice of titanium are calculated. A probability of formation of a more energetically favorable structure is shown than that of NaCl, which is well-known from the phase diagram of Ti–C. The results of calculations of lattice parameters, elasticity moduli, and charge density distribution in the predicted phase are presented. The relationship between the atomic structure peculiarities and the chemical bonding type in this phase is discussed. [ABSTRACT FROM AUTHOR]

Sub-fractions of all apo B-100 containing lipoproteins (low density lipoproteins, very low density lipoproteins and intermediate density lipoproteins) with reduced contents of sialic acid were found in vivo in human blood. These lipoproteins were inclined to spontaneously form aggregates and were able to stimulate accumulation of cholesterol in cells cultured from human aortic intima. In vitro treatment of apo B-containing lipoproteins with 2,6- and 2,3-specific sialidases, α-mannosidase, endoglycosidases F1 or F2 or peptide-N-glycanase F also stimulated aggregation and increased the ability of these particles to potentiate cholesterol accumulation in cells of the intact human aortic intima. So, deglycosylation of various apo B-containing lipoproteins possibly occurs in the blood, decreases their resistance to aggregation and increases the ability of these particles to stimulate accumulation of cholesterol in human aortic intima cells, thereby increasing their atherogenic potential. [ABSTRACT FROM AUTHOR]

The cerebellar interposed nuclei (IN) are critical components of a neural network that controls the expression of classically conditioned eyeblinks. The IN receive 2 major inputs: the massive, gamma-aminobutyric acid (GABA)-mediated input from the Purkinje cells of the cerebellar cortex and the relatively weaker, glutamate-mediated input from collaterals of mossy and climbing fiber cerebellar afferent systems. To elucidate the role of IN glutamate neurotransmission in conditioned response (CR) expression, effects of blocking fast glutamatergic neurotransmission in the IN with gamma-d-glutamylglycine (DGG) on the expression of conditioned eyeblinks and on cerebellar nuclear neuronal activity were examined. Surprisingly, blocking fast glutamate receptors in the IN did not abolish CRs. DGG decreased CR incidence and slightly increased CR latency. In contrast, identical amounts of DGG applied to the cerebellar cortex abolished CRs. Similar to the behavioral effects, DGG had unexpectedly mild effects on IN neurons. At the population level, the baseline firing frequency of IN cells was not affected. After DGG injections, the incidence of excitatory modulation of cell activity in the interstimulus interval decreased but was not abolished. A combined block of fast glutamate and GABA(A) neurotransmission using a mixture of DGG and picrotoxin dramatically reduced CR incidence, increased the firing frequency of all cell types, and virtually abolished all modulation of neuronal activity. These results indicate that fast glutamate neurotransmission in the IN plays only an accessory role both in the expression of behavioral CRs and in the generation of associated neuronal activity in the IN. [ABSTRACT FROM AUTHOR]

Increasing the exhaustiveness of refining due to depletion of easily refined crude oil resources is basically attained by improving the catalytic systems and revamping the process units, which increases the cost of the processes and in the final analysis, the cost of the finished products. [ABSTRACT FROM AUTHOR]

The cerebellar interposed nuclei (IN) are an essential part of circuits that control classically conditioned eyeblinks in the rabbit. The function of the IN is under the control of GABAergic projections from Purkinje cells of the cerebellar cortex. The exact involvement of cerebellar cortical input into the IN during eyeblink expression is not clear. While it is known that the application of gamma-aminobutyric acid-A (GABA(A)) agonists and antagonists affects the performance of classically conditioned eyeblinks, the effects of these drugs on IN neurons in vivo are not known. The purpose of the present study was to measure the effects of muscimol and picrotoxin on the expression of conditioned eyeblinks and the activity of IN cells simultaneously. Injections of muscimol abolished conditioned responses and either silenced or diminished the activity of IN cells. Two injections were administered in each picrotoxin experiment. The first injection of picrotoxin slightly modified the timing and amplitude of the eyeblink, produced mild tonic eyelid closure, increased tonic activity of IN cells, and reduced the amplitude of the neural responses. The second injection of picrotoxin abolished conditioned responses, further increased tonic eyelid closure, dramatically elevated the tonic activity of IN cells, and in most cases, abolished neuronal responses. These results demonstrate that both GABA(A)-mediated inactivation and tonic up-regulation of IN cells can interrupt the expression of conditioned eyeblinks and that this behavioral effect is accompanied by the suppression of the neuronal activity correlates of the conditioned stimulus and response. [ABSTRACT FROM AUTHOR]

The effect of hot rolling on the structure and mechanical properties of a Zn‑0.8Li zinc alloy is studied. It is found out that as a result of hot rolling, the alloy dendritic structure is transformed into a granular structure in eutectic regions with an average grain size of 4.6 μm, and the primary β‑LiZn4 phase acquires the boundaries of the regions elongated in the rolling direction with the dimensions of 100 μm in the cross section and 300–500 μm in the longitudinal section. It is shown that the formation of the grain structure by rolling leads to a significant increase in the yield strength, tensile strength, and the development of plasticity. [ABSTRACT FROM AUTHOR]

A new means of measuring the thermal and heating engineering parameters of materials and constructions, employed in monitoring and diagnostics, is proposed. Some problems that arise during measurements are also considered. [ABSTRACT FROM AUTHOR]

A physical model method allows the estimation of the strain inhomogeneity in a material subjected to equal channel angular pressing. Copper samples which deformed with ECAP with a standard die-set showed significant inhomogeneity. The sample section was split into two sections, which have significantly different values of accumulated strain and, as a consequence in the microstructure. Application of a die-set with a special geometry modification allows uniform strain across the sample. A comparative analysis of physical modeling results, changes of microstructure and properties showed complete correlation. Known theoretical models of the ECAP process with deformation modes close to simple shear are analyzed. [ABSTRACT FROM AUTHOR]

The polarization of the secondary protons in the ( p, 2 p) reaction with the S-shell protons of nuclei He, Li, C, Si, Ca was measured at 1 GeV unpolarized proton beam. The spin correlation parameters C for the He and C targets also were for the first time obtained as well. The polarization measurements were performed by means of a two-arm magnetic spectrometer, each arm of which was equipped with the multiwire-proportional chamber polarimeter. This experiment was aimed to study a modification of the proton-proton scattering matrix in the nuclear medium. [ABSTRACT FROM AUTHOR]

The possibility of manufacturing high-octane gasolines and winter diesel fuel with a low n-alkane and aromatic hydrocarbon content from high-sulfur petroleum distillates with an endpoint under 350°C in one stage was demonstrated. The octane number of the gasolines is regulated by the mass feedstock space velocity. The catalyst used allows obtaining environmentally clean high-octane gasolines and diesel fuels without additional hydrotreating. [ABSTRACT FROM AUTHOR]

A new method for synthesizing 11H-indolo[3,2-c]quinolines by SnCl4-catalyzed intramolecular electrophilic amination of 2-arylindole-3-carbaldehyde O-acetyl oximes was developed. [ABSTRACT FROM AUTHOR]

A new method for the synthesis of 6,7-dimethoxy-3,4-dihydroisoquinoline based on the reaction of 2-(3,4-dimethoxyphenyl)ethan-1-amine (homoveratrylamine) with aliphatic nitro compounds in polyphosphoric acid (PPA) was developed. [ABSTRACT FROM AUTHOR]

The fracture behavior of Cu - 0.1% Sn alloy in samples of two types, namely with similar characteristics of ultra-fine-grained structure, but different in the second phase particle size has been investigated. These two types of samples were obtained by means of equal channel angular pressing with different number of passes. It has been found that with increase in the total strain the morphology and orientation of the fracture surface demonstrate changes corresponding to the development of shear mode. The arguments for the hypothesis that the fracture behavior change is connected with the decrease of the particle size and increase of their distribution density are given. [ABSTRACT FROM AUTHOR]