Prospects of nanoparticle application in contact materials of urban electric transport

Investigation results for electrocontact materials based on silver and copper and modified by nanoparticles are presented. Their optimum compositions; technological production features; and physical, mechanical, and operational properties are determined and the microstructure is studied. It is shown possible to replace the standard, widely applied electrocontact materials and Ag-containing products with copperbased pseudoalloys with nanoparticle additives. Prospects of innovation for the investigative results are considered.     

Operation of two induction motors on a dissipative elastic base

The motion of two unbalanced rotors on a dissipative elastic base is investigated. The conditions corresponding to steady synchronization are determined, as well as the dissipation conditions.     

Information-thermodynamic principle of the organization of chemical engineering systems

The information entropy-based quantitative interpretation of Roullier’s evolutionary law of the system organization of organisms is given as applied to chemical engineering systems. The relationships characterizing the optimal distribution of expenses on the organization of objects were derived for multipurpose processes and multiroute systems from the viewpoint of creating a highly organized chemical engineering system.     

Synchronization of two motors on an elastic base

Effects associated with the synchronization of two motors on an elastic base are investigated. Spectral analysis reveals informative harmonics that permit determination of the order in which the motors must be switched on prior to synchronization.     

3D Printing to Increase the Flexibility of the Chemical Synthesis of Biologically Active Molecules: Design of On-Demand Gas Generation Reactors

The development of new drugs is accelerated by rapid access to functionalized and D-labeled molecules with improved activity and pharmacokinetic profiles. Diverse synthetic procedures often involve the usage of gaseous reagents, which can be a difficult task due to the requirement of a dedicated laboratory setup. Here, we developed a special reactor for the on-demand production of gases actively utilized in organic synthesis (C₂H₂, H₂, C₂D₂, D₂, and CO₂) that completely eliminates the need for high-pressure equipment and allows for integrating gas generation into advanced laboratory practice. The reactor was developed by computer-aided design and manufactured using a conventional 3D printer with polypropylene and nylon filled with carbon fibers as materials. The implementation of the reactor was demonstrated in representative reactions with acetylene, such as atom-economic nucleophilic addition (conversions of 19–99%) and nickel-catalyzed S-functionalization (yields 74–99%). One of the most important advantages of the reactor is the ability to generate deuterated acetylene (C₂D₂) and deuterium gas (D₂), which was used for highly significant, atom-economic and cost-efficient deuterium labeling of S,O-vinyl derivatives (yield 68–94%). Successful examples of their use in organic synthesis are provided to synthesize building blocks of heteroatom-functionalized and D-labeled biologically active organic molecules.     

Software Package for Modelling Transient Processes in Controlled Objects

We consider the main stage of design for control systems, i.e., simulation of the transient process, which requires a large volume of precise computation associated with evaluating the operation of the prospective system and optimal tuning of controller parameters.     

Structural states of aluminum-lithium alloy 1469 sheets

The texture and microstructure of the central layers in alloy 1469 sheets and the orientations of hardening T₁-phase precipitates are studied by X-ray diffraction, optical microscopy, and transmission electron microscopy. These studies and X-ray diffraction performed in asymmetric geometry demonstrate that the texture of the material is formed by the broadening of the orientations located near a β skeleton line. The contribution to an X-ray diffraction pattern from two of the four possible versions of the orientations of hardening T₁-phase plates that are caused by a brass-type texture component in the matrix and the orientation relationships between the matrix and the T₁-phase lattices is separated. The microstructure of the sheets is shown to have a two-level character. It is formed by extended (up to several millimeters long) regions fragmented into grains several microns in size. The structural states of the sheet material are discussed in their relation to the crystallographic character of fatigue crack propagation.     

Local triboelectrification of an n-GaAs surface using the tip of an atomic-force microscope

The method of scanning Kelvin-probe microscopy is used to show that the effect of triboelectrification is observed when the tip of an atomic-force microscope interacts with the surface of n-GaAs epitaxial layers. The sign of the change in the potential indicates that the sample surface after triboelectrification becomes more negative. The observed specific features of the phenomena can be attributed to the thermally activated generation of point defects in the vicinity of the sample surface due to deformation caused by the tip.