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A review of new results on the application of layer-by-layer (LbL) chemical assembly procedures to the production of thin-layer structures on the surfaces of various substrates in order to develop active elements (AEs) of chemoresistive gas sensors for the determination of inorganic and organic compounds in air and controlled gas atmospheres is presented. The LbL assembly procedures and their features, such as the possibility of synthesis under the conditions of soft chemistry, the precise setting of the thicknesses of applied layers, and the production of multilayers consisting of individual layers with predicted compositions, are considered. Charge transfer between analyte molecules in the layers and oxidation-reduction centers on the AE surface is briefly discussed, and conditions for the functioning of optimal AEs are formulated. The capabilities of the LbL assembly method to precisely control the thickness of each layer in a multilayer system on the electrode surface and thus directionally change the sensor response and select a layer responsible for the best practically important characteristics are emphasized. The role of catalysts in these processes is noted. The results of original publications on the application of LbL assembly procedures to the development of a wide range of AEs for sensors are presented, and the analytical characteristics of the sensors are compared. In conclusion, the prospects for using these procedures in the manufacture of new AEs with high sensitivity and selectivity and a short response time are considered., Author(s): V. P. Tolstoy [sup.1], A. A. Golubeva [sup.1], E. O. Kolomina [sup.1], D. V. Navolotskaya [sup.1], S. S. Ermakov [sup.1] Author Affiliations: (1) grid.15447.33, 0000 0001 2289 6897, St. [...]

We studied methods of the in situ synthesis of gold nanostructures on the electrode surface and of the directed electrochemical synthesis of nanodendrites to create biosensors based on horseradish peroxidase. The effect of nanostructuring of the transducer surface and its subsequent modification on the electroanalytical characteristics of sensors for the determination of hydrogen peroxide was studied. The use of these methods can significantly improve the performance characteristics of the biosensors, such as the sensitivity coefficient, limit of detection, and stability in the range of micromolar and submicromolar concentrations of hydrogen peroxide. The electrodes modified by the in situ synthesis of nanostructures with subsequent treatment with Meerwein's reagent, as well as ultramicroelectrodes prepared by directional electrochemical synthesis, show low limits of detection for hydrogen peroxide, 0.2 and 0.08 [micro]M, and high sensitivity coefficients, 0.71 and 0.84 A M.sup.-1 cm.sup.-2, respectively., Author(s): K. G. Nikolaev [sup.1], S. S. Ermakov [sup.2], Yu. E. Ermolenko [sup.2], D. V. Navolotskaya [sup.2], A. Offenhäusser [sup.3], Yu. G. Mourzina [sup.3] Author Affiliations: (1) grid.35915.3b, 0000 0001 [...]

The paper provides the analysis of problems associated with the evaluation of difference between the mass of received and handed over cargo in determining the masses by draft survey and due to the difference in the measurement conditions at the loading and unloading ports (due to the change errors in various stages of the measurement procedures). The errors that may arise in determining the mass of the cargo due to roughness when measuring draft, due to using the inclinometer to determine the draft from one of boards, due to instrumental errors in the determination of the density of seawater, due to other possible errors have been investigated and evaluated. To estimate the errors of draft due to heaving and errors of inclinometer some formula are to be applied, their derivation has been done in this paper. It has been recommended to use the traditional formula of high-speed drawdown with the replacement of vessel speed on current rate to calculate the error of precipitation arising from the drawdowns ship on a current. The value per unit displacement draft from loading scale has been used to evaluate the error of the displacement appearing in the presence of draft errors. As a result two similar criteria (rigorous and statistical) of allowable discrepancies calculated by draft survey mass of cargo in the port of loading and port of discharge have been substantiated. These criteria require the calculation and accumulation in a table of all the errors and calculate the total error of displacement. Criteria will allow the consignee and the carrier come to a reasonable and agreed decision about the significance of differences of the masses taking into account the indifference of conditions and measuring instruments.

The authors have offered and proved the following security options of pelagic trawling in the sea canyon: the tolerance of the vessel from the optimal track; the minimum width of the canyon giving opportunity for the conditions to ensure the safety of the trawl; margin width of the canyon on the trajectory of the trawl maneuvering due to changes in the direction of the canyon axis; deviation from the axis of the trawl canyon maneuvering owing to changing the axis direction at any time after rotation; time when the deviation of the trawl from the canyon axis while maneuvering owing to changing the axis direction reaches some predetermined value

Changes in reproductive behavior among young people in Russia, changing patterns of marriage and family formation, and high death rates among males are all affecting Russia's human capital potential, and public policy reforms will need to take this into account. The new Federal Law "On Youth Policy" represents an important stage that should lead to more focus on young people. To substantiate the most urgent relevant measures of youth policy in this law, it is appropriate to analyze the social and demographic problems of youth in the Russian Federation. This article examines the main components that ensure the population's growth: birth rate, marriage rate, and mortality rate as these apply to young people, for the purpose of drawing up recommendations for federal bodies of legislative and executive authority, thus promoting fuller realization of the demographic potential of young people.