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Spatial distributions of the electron temperature and intensity of luminescence of molecular complex C2 are measured in the plasma jet of an optical discharge in a mixture of argon with molecular additives, supported by continuous CO2 laser radiation. Diamond coatings are obtained on cutting inserts of a turning tool made of WC-Co8 hard alloy by scanning a plasma jet along the surfaces of the inserts, and diagnostics of the coatings are performed. [ABSTRACT FROM AUTHOR]

Superhydrophobic coating is obtained by cathodic deposition of copper from a solution of 0.25 M CuSO4 + 0.5 M H2SO4 at a current density of 0.25 A/cm2 for 30 s on copper foil, followed by exposure to 0.01 M ethanolic solution of stearic acid for 1 h. The wetting angle of the water-formed coating is 155°–157°. Corrosion testing of copper samples with the resulting coating is carried out in a temperature-humidity chamber for 40 days, in an atmosphere with 100% humidity for 186 days and under conditions typical for livestock buildings, at 100% humidity and in the presence of CO2 corrosion accelerators, H2S and NH3 in pairs and simultaneously all three in maximum permissible concentrations for 46–56 days. In all cases, the coatings retain their superhydrophobicity, the wetting angle either remained almost unchanged or decrease by 2°–3°, and there is no corrosion damage on the samples. The influence of the copper electrodeposition mode from the solution of 0.25 M CuSO4 + 0.5 M H2SO4 on the wetting angle of the resulting coating is evaluated. [ABSTRACT FROM AUTHOR]

The spatial distributions of the electron temperature and the emission intensity of the C2 molecular complex in a plasma jet of a continuous optical discharge in the mode of a laser plasmatron supported by the radiation of a cw CO2 laser operating on a mixture of Ar with molecular additives have been measured. Diamond coatings have been obtained on the cutting inserts of a turning tool made of WC8 hard alloy; diagnostics of the coatings have been carried out. [ABSTRACT FROM AUTHOR]

Interactions between the endoplasmic reticulum (ER) and mitochondria have received insufficient attention until recently. However, distorted contacts between the ER and mitochondria were identified as an important factor in the etiopathogenesis of neurodegenerative diseases, such as Alzheimer's disease, Parkinson's disease, and amyotrophic lateral sclerosis. In view of these new data, the mechanisms of ER–mitochondrial interactions are necessary to study in detail in order to develop new diagnostic and therapeutic approaches to neurodegenerative diseases and to extend basic knowledge of the physiology of the eukaryotic cell. The review focuses on the functions of mitochondria-associated ER membranes (MAMs). Structural elements of the MAM system, their contributions to the vital cell functions (calcium and lipid homeostasis, autophagy, fusion and division of mitochondria, and the regulation of their number), and the role of MAM dysfunctions in the pathogenesis of various neurodegenerative diseases are considered. [ABSTRACT FROM AUTHOR]

The optical and electromagnetic properties of graphene oxide (GO)-modified WO3 electrochromic nanocomposite films obtained by electrochemical deposition of the W and GO ions from a solution synthesized using peroxotungstic acid (PTA) with the addition of GO were studied. Controlled electrochemical deposition of electrochromic WO3 films was carried out by the multistage amperometry (MSA) procedure in which the initial and final values of the electrodeposition potential of –0.5 and –1.5 V, as well as the number of cycles were set. [ABSTRACT FROM AUTHOR]

The protective effectiveness of oil compositions in the presence of sulfur dioxide was studied. The moisture permeability of oil films and the corrosion rate of steels both protected and unprotected by oil films increase with increasing relative humidity and initial sulfur dioxide concentration in the atmosphere. The contribution of individual components to the protective effect of a film of synthetic Mobil-1 oil inhibited by the additive Emulgin in the presence of sulfur dioxide is considered. The total protective effectiveness of the system can reach 93-96% after one day in 0.5 M sodium chloride solution containing sulfur dioxide and the products of its interaction with water. The slowdown of steel corrosion under a layer of inhibited and non-inhibited oil film is mainly due to retardation of the cathodic process with slight inhibition of the anodic reaction. [ABSTRACT FROM AUTHOR]

The properties of petroleum and synthetic oils used as bases for anti-corrosion materials are determined. The viscosity-temperature characteristics determine the feasibility of applying oil coatings. Regression equations allowing the thickness of the resulting protective film to be calculated as a function of the oil viscosity are obtained. Results from wettability assessments indicate that the oil surface is hydrophilic. The oil films are permeable to water; stimulants, and corrosion inhibitors. Films of the studied oils inhibit anodic dissolution of steel and accelerate slightly cathodic reduction of oxygen. The nature of the oil base has little effect on the protection effectiveness if anti-corrosion additives Emulgin or Mobiin-3 are added at concentrations wt. %. [ABSTRACT FROM AUTHOR]

The sorption of surface-active substances (surfactants), namely, C18–C21 synthetic fatty carboxylic acids (distillation residues of their production), a number of amines, and amides from films of pure, normal paraffinic hydrocarbons such as heptane, octane, nonane, decane, and pentadecane deposited on St3 steel immersed in 0.5 M NaCl solution, has been studied. Concentrations have been obtained at which the degree of surface filling with surface-active substances approaches unity. It is shown that surfactant adsorption takes place on an energetically inhomogeneous surface, and it seems that in a number of cases it is realized by the donor-acceptor interaction mechanism. [ABSTRACT FROM AUTHOR]

A qualitative and quantitative system of criteria for evaluating the universality of volatile metal corrosion inhibitors (VCIs) with respect to agricultural production conditions has been developed. The system of qualitative criteria for universalism includes (1) assessment of the effectiveness of metal corrosion inhibition under the conditions of the individual or combined action of corrosion-specific stimulators in the vapor-gas phase; (2) suppression of different types of local corrosion that they cause in the corrosion medium; (3) suppression of the general and local corrosion of contacting-metal structural materials with different compositions under specific conditions; and (4) the observance of acceptable specific characteristics of VCIs: ecological characteristics and characteristics related to the hazard class and influence on chemical oxygen consumption (COC) and biochemical oxygen demand for the biodegradation of substances by microorganisms (BOD5). The system of quantitative criteria for the universalism of VCIs includes quantitative parameters for all proposed qualitative points. It is also proposed to introduce a simplified assessment for agricultural-production conditions by characterizing partially universal inhibitors, which reduces operation costs. Experimental data are given for the IFHAN-114 volatile inhibitor as an example of the effectiveness of the proposed criteria. It is shown that IFHAN-114 is a partially universal inhibitor. [ABSTRACT FROM AUTHOR]

To simulate conditions for evaluating the inhibition efficiency of an IFKhAN-114 volatile inhibitor under atmospheric corrosion of copper in the presence in the air of two corrosion promoters CO2 + NH3 or H2S + NH3, polarization measurements were performed. For this purpose, 0.1 M NaCl solution containing, in a wide range of concentrations, the products of the hydrolysis of ammonium carbonate or ammonium sulfide was used. Comparison of the data obtained through weight loss tests (the first method) and polarization measurements (the second method) showed that the latter approach allows obtaining only qualitative data, which, however, requires significantly less time than the first one. [ABSTRACT FROM AUTHOR]

At room temperature, moisture, SO2, and oxygen permeability of mineral oils, i.e., industrial I‑20A, M-10G2(K) (product and waste, MWO), rapeseed, and sunflower are studied. It is shown that all the studied oils are highly permeable to H2O, SO2, and O2 molecules. For the moisture and SO2 permeability of the studied oils, the following dependences are typical: m(H2O) = ai + biτ and m(SO2) = li + kiτ. The values of ai and li are determined by the nature of the base solvent and the concentration of thickeners (PVK, IFKhAN-29A), which can both suppress and stimulate oxygen permeability. [ABSTRACT FROM AUTHOR]

The protective ability of the volatile IFHAN-114 inhibitor in the corrosion of models of macrogalvanic steel/brass, steel/copper, and copper/brass pairs under conditions simulating the atmosphere of livestock premises is studied. The content of CO2, NH3, and H2S (corrosion stimulators) was 0.2–0.6 vol %, 20–60 mg/m3, and 10–30 mg/m3, respectively. The ability of IFHAN-114 to suppress the generation of the faradaic current by the models of galvanic pairs is investigated. It is shown that the surface of metals forming the galvanic pairs undergoes intensive pitting and ulcer corrosion when there is no inhibitor under the effect of one corrosion stimulator (CS) or simultaneous effect of two or three corrosion stimulators. In most cases, the introduction of IFHAN-114 into the gas phase completely suppresses the local corrosion of metals forming the galvanic pairs and reduces the rate of their general corrosion (which is uniform when the volatile corrosion inhibitor is used) by 2–5 times. The inhibitor introduced into the 0.1 M KCl solution significantly suppresses the density of the current generated by the models of galvanic steel/brass and copper/brass pairs. However, this effect is observed only after 200 min of exposure of the pair models to corrosion. [ABSTRACT FROM AUTHOR]

A technique for the evaluation of the partial contributions of individual components of anticorrosion protective systems (PSs) to their integrated efficiency under the metal corrosion of any nature in the gas or liquid phase and under the conditions of underground corrosion regardless of the nature of an aggressive medium and PS components was proposed. The contributions of components and their different concentrations to the integrated efficiency of protective systems can be evaluated by any moment of time from the beginning of corrosion. The proposed technique is the theoretical basis for the development of new multicomponent protective materials, which is shown by adducing a specific example. [ABSTRACT FROM AUTHOR]

The corrosion and kinetics of partial electrode reactions on St3 carbon steel with a superhydrophobic coating based on methoxy fluorobutylsilane derivatives in 0.5 M NaCl solution were studied. This influence of in situ duration τ of the medium's corrosive action (0.5-144 h) on its protective effect is considered. This allows reduction of overall corrosion rate by 23 ± 3 times, when the stationary state is reached. The kinetics of cathodic reduction of dissolved oxygen and steel anodic ionization is also considered. In the initial stages of corrosive action of neutral aerated chloride medium (until steady-state characteristics are reached), steel at potential E near Ecor corrodes in the active state, whereas, when τ is ≤0.5 h, it corrodes under anodic control conditions, and then the control is replaced with a cathodic one. [ABSTRACT FROM AUTHOR]

It is known that brass is the construction material widely used when manufacturing agricultural equipment. An effective volatile inhibitor is offered to protect it from corrosion in the atmosphere of the livestock premises with 100% and close to it relative humidity of the air containing the stimulators of this process-CO, NH, H2S-in the concentrations that multiply exceed the background ones. A range of methods-weight corrosion tests and electrochemical measurements (potentiodynamic polarization, polarization resistance, fixed in the automatic mode)-define the conditions under which the inhibitors of the IFKHAN series multiply slow down the corrosion of brass. The general corrosion rate of L62 brass is decreased ten times in the presence of all studied inhibitors of this series in the atmosphere containing up to 20 mg/m of HS and 100% relative humidity. It is most reasonable to use the IFKHAN-112 inhibitor with the ammonia content up to 30 mg/m in the maximum humid atmosphere. [ABSTRACT FROM AUTHOR]

High-efficient volatile inhibitors are offered for protection against corrosion of steel agricultural equipment located on livestock premises in the atmosphere with the relative humidity of approximating 100% and containing the maximum allowable concentration of the corrosion stimulants-CO, NH, HS-for these conditions. It is shown using the method of the weight corrosion tests and electrochemical potentiodynamic measurements that, in the presence of up to 25 mg/m of CO, the IFKhAN-8, IFKhAN-112, and IFKhAN-118 volatile inhibitors of new generation permitted the almost complete suppression of the corrosion of the carbon steel St3. In the presence of these inhibitors in the atmosphere containing up to 20 mg/m of HS and 100% relative humidity, the rate of the general corrosion of this steel is reduced 30 times and more. Only in the presence of up to 30 mg/m of ammonia in the maximum humid atmosphere is the corrosion suppressed two times. In the latter case, it is most reasonable to use the IFKhAN-112 volatile inhibitor with the pressure of the saturated vapor of 0.133 Pa. [ABSTRACT FROM AUTHOR]

Kinetics of electrode reduction reactions of dissolved molecular oxygen and hydrogen ions upon corrosion of copper and carbon steel was studied in neutral (NaCl) and weakly acidic (HCl) media. It was shown that deposition of the films comprised of trade or waste petroleum and synthetic (poly-α-olefins) oils on the studied metals does not alter the kinetic parameters of the electrode processes both in the kinetic region and in controlling mass transfer conditions. The observed regularities were explained as being results of the high porosity of the used oil films regardless of their kind. [ABSTRACT FROM AUTHOR]

This article suggests a highly effective volatile inhibitor for anticorrosion protection of agricultural equipment stored in closed premises with a highly aggressive atmosphere. The protective efficiency of IFHAN-118 new-generation volatile inhibitor has been studied by weight corrosion tests and electrochemical potential dynamic measurements at corrosion of St3 steel and L62 brass in the atmosphere with 100% relative air humidity and in 0.1 M of NaCl solution. For 1360 hours of exposure to the environment, the rate of steel corrosion dropped hundredfold. The protective effect of the inhibitor on brass is much weaker. In different periods of exposure to the environment, the corrosion rate dropped 6.5-to-9-fold. In neutral 0.1 M NaCl solutions, IFHAN-118 significantly inhibits the anode reaction of metal ionization on steel. Applied to brass, IFHAN-118 also slows down the cathode recovery of dissolved oxygen (500 mg/L); this is the only cathode reaction in the studied conditions. As shown by polarization measurements, IFHAN-118 is an efficient corrosion inhibitor in animal farming premises, tropical and subtropical climate, and marine atmosphere, when the surface moisture phase film can be saturated with alkaline metal chlorides. The optimal inhibitor concentration on steel and brass surfaces is 150 and 5 mg/L, respectively. [ABSTRACT FROM AUTHOR]

Hydrosilylation of allyl glycidyl ether with triethoxysilane in presence of Speier’s catalyst leads to triethoxy(3-glycidoxypropyl)silane and triethoxy(2-glycidoxy-1-methylethyl)silane and is accompanied by isomerization of allyl glycidyl ether and cleavage of the oxirane ring and the ether bond. An effect of admixtures in allyl glycidyl ether on the process is revealed. Some other hydrosilylation catalysts and additives to Speier’s catalyst are studied [ABSTRACT FROM AUTHOR]

The fractional composition of M-10G2(k) used motor oil was determined. The effect of its component son the protective effectiveness was investigated. Resins and asphaltenes, primarily neutral resins, make the basic contribution to the inhibiting effect. [ABSTRACT FROM AUTHOR]

We estimate the reliability of previously derived normal energy distributions for stars by comparing normal color indices in three photometric systems (WBVR, uvby, and Vilnius) calculated using these distributions with indices derived from photometric observations. Earlier, we used photometric data from WBVR and uvby catalogs to derive normal color indices for these systems not available in the literature, in the form of mean color indices and indices obtained for representative groups of normal, unreddened stars. The results can be used to estimate both the quality of our normal distributions and the reliability of the normal color indices in the three photometric systems considered.© 2002 MAIK “Nauka / Interperiodica”. [ABSTRACT FROM AUTHOR]

We have derived the normal spectral energy distributions for those early-type subgiants, giants, and supergiants that were not investigated in our earlier studies, which were in most cases also not included in the studies of Sviderskiene. Color indices computed using our normal energy distributions are in good agreement with normal colors derived from observations in the Vilnius photometric system. The reliability of our distribution curves is also demonstrated by comparisons of observed and computed (W–B)–(B–V) two-color diagrams in the WBVR system. Normal color indices for the photometric WBVR system are derived. © 2000 MAIK “Nauka / Interperiodica”. [ABSTRACT FROM AUTHOR]

The color indices of the Sun in the u[vee]by system are calculated using the spectral energy distribution of Lockwood, Tug, and White. This allows errors in the absolute calibration to be excluded from the calculated color indices. The normal position of the Sun on the ([vee] – b)–(b–y) and ([vee] – y)–(b–y) color–color diagrams for early G stars testifies to the absence of any significant peculiarities in the Sun compared to other stars of similar spectral type. These diagrams can provide a useful tool in searches for candidate solar analogues among faint stars. © 2000 MAIK “Nauka / Interperiodica”. [ABSTRACT FROM AUTHOR]

A calculation-experimental method has been developed for determining the life of welded assemblies of thin-walled connections in the holes of thick-walled pressure vessels. A model of a connection is calculated with use of the finite element method and the number of load cycles at a given level of cyclic load necessary for determination of life is established. The results of experimental investigations make it possible to determine more accurately the effective concentration factor determining the cyclic strength of such a type of structure and also the safety factors. [ABSTRACT FROM AUTHOR]

Postnatal ontogeny of sympathetic ganglia includes both proliferative processes and programmed cell death. Electron microscopy helps to evaluate the intensity and the relationship between these processes. [ABSTRACT FROM AUTHOR]

The color indices of the Sun have been calculated from their absolute energy distribution and the response functions of photometric bands V, J, H, K, L, and M. The color indices of the Sun are compared with those of the solar-like stars. [ABSTRACT FROM AUTHOR]