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Inspired by the bioactivity of natural compounds with a bicyclo[3.3.0]octane core, the study focuses on developing tetrahydropentalene-2,5-dione (2,5-THP-dione) derivatives as potential building blocks for the use in medicinal chemistry. Using the commercially available 2,5-THP-dione, a number of alkylated derivatives and a monofunctional ketone were synthesized. Using optimized protocols for synthesis, target compounds were obtained with high yields on a multigram scale. These compounds are promising derivatives for further chemical derivatization and therapeutic use, and thus highlight the value of 2,5-THP-dione in creating complex molecular structures for drug discovery, as well as the importance of tetrahydropentalene derivatives as valuable building blocks in synthetic chemistry. [ABSTRACT FROM AUTHOR]

It was determined that in an electrolyte containing 1.75 g/L KOH+1 g/L Na2SiO3+2 g/L NaAlO2, with an increase in current density from 15 A/dm² to 50 A/dm², the phase composition of the coating changes. In the three-phase state (aluminum titanate, rutile, and amorphous-like phase), with increasing j, instead of an amorphous-like phase, a crystalline mullite phase appears. The hardness of the coating increases from 5400 MPa to 12500 MPa. It was found that, in combination with aluminum titanate, mullite is the basis for achieving high hardness in the coating. The formation of a ceramic micro-arc oxide coating on the surface of the VT3-1 titanium alloy makes it possible to reduce the dry friction coefficient by more than 5 times to f=0.09. The effect of electrolysis conditions during micro-arc oxidation of the VT3-1 alloy (titanium-based) on the growth kinetics, surface morphology, phase-structural state, and physical and mechanical characteristics (hardness, coefficient of friction) of oxide coatings was studied. It was found that the process in the mode of micro-arc discharges is stably implemented on the VT3-1 alloy in an alkaline (KOH) electrolyte with additions of sodium aluminate (NaAlO2) and liquid glass (Na2SiO3). This makes it possible to obtain coatings up to 250 μm thick. In this case, a linear dependence of the coating thickness on the time of the MAO process is observed. The growth rate of the coating increases with increasing current density. The highest growth rate was 1.13 μm/min. It was revealed that in an electrolyte containing 1 g/L KOH+14 g/L NaAlO2 with an increase in the duration of oxidation from 60 to 180 minutes, the relative content of the high-temperature phase, rutile, increases. In the coatings obtained in the electrolyte 1.75 g/L KOH+1 g/L Na2SiO3+2 g/L NaAlO2, with an increase in the duration of the MAO process, the relative content of the amorphous-like phase decreases and the content of the crystalline phase of mullite (3Al2O3·2SiO2) increases. [ABSTRACT FROM AUTHOR]

In connection with the active development of information systems in transport, it becomes necessary to integrate vehicles, infrastructure and humans into a single information network. The V2I system of information analysis for monitoring and controlling vehicles in operating conditions is an organic combination of information and analytical components. The latter includes the analysis of information regarding changes in operating conditions. The article presents a study that has improved the processes of managing the operating conditions of vehicles in the V2I communication system by using simulation modelling. A simulation model for choosing the optimal operating conditions for vehicles is described. The model takes into account road, climatic, and transport conditions and culture of vehicle operation, as well as the peculiarities of public transport movement in a transport hub. The objective function with the appropriate restrictions and the problem of traffic optimization in the investigated transport hub were established. Diagrams of the processes of the simulation model were constructed for various input parameters, including the optimal ones, with the creation of corresponding agents and their populations. Models of public transport delays at stops using a triangular distribution were developed, and the corresponding hypotheses were confirmed by Pearson's test (χ2). The developed models can be used in the process of rebuilding a transport hub, as well as for modeling traffic when the operating conditions of vehicles change and for predicting such changes. The simulation results can be used in the creation and design of intelligent transport systems. [ABSTRACT FROM AUTHOR]

Problem. The article analyzes the design features of the systems and components of the Tesla Model S electric car, which allows choosing the initial characteristics for the mathematical model of the acceleration dynamics of the electric car, determines the cost characteristics of its power plant (electric motor) and battery. Goal. The purpose of the work is to determine the initial characteristics of the systems and components of a modern electric vehicle for their further use in a mathematical model of the acceleration dynamics of an electric vehicle. Methodology. The approaches adopted in the work to achieve the set goal include understanding the peculiarities of the initial characteristics of the systems and components of electric vehicles, which are the world leaders in the market of such vehicles. Results. In the work, a comparative analysis of the layout schemes for the implementation of transmissions in the designs of modern electric vehicles, the characteristics of their power plants (electric motors), the characteristics of energy converters (inventories), and the features of the power plant power plant of a modern electric car are determined. Originality. The conducted analysis of the design features of systems and components of the Tesla Model S electric car made it possible to form a general idea about the features of the implementation of work processes in the electric drive of an electric car, which can be used as initial parameters or characteristics during the simulation of the acceleration dynamics of an electric car. Practical value. The obtained results make it possible to formulate recommendations for the use of the characteristics of the systems and components of the electric vehicle during the simulation of the dynamics of its acceleration and to determine the energy consumption in the power system of its traction electric drive.

Problem. The article is devoted to the problem of improving the environmental safety of electric vehicles and reducing energy costs for their movement. Only in 2019, 2.6 million electric cars are planned to be sold, which will increase their total number to 7.6 million. The investments in development of electric vehicles double annually. In this study, the justification of the energy intensity and the corresponding mass of TAB for electric vehicles driven in the mode of “only electricity” was conducted. The most promising hybrid vehicles are those that are capable of generating energy in the TAB from stationary sources of electricity, the so-called Plug-in Hybrid Vehicle (PHV) system. Goal. The goal is achieved by justifying the capacity of traction batteries for powering hybrid vehicles, hybrid electric vehicles, electric vehicles. Methodology. To increase the economy and ecological safety of the vehicles, an experimental hybrid vehicle based on ZAZ Lanos Pickup was created at the Department of Automobile Electronics of KhNAHU, which was also selected as an analogue. The Lanos Pickup Hybrid ZAZ uses a 15 kW electric motor, the TAB includes 20 TS-LFP90AHA lithium iron phosphate batteries with a total capacity of 5.76 kWh. The mass of the TAB unit does not exceed 65 kg. The Department of Automobile Electronics conducted full-scale tests of the hybrid ZAZ Lanos Pickup under real operational conditions. Conclusions. The calculation results show that the maximum mass of an electric vehicle's TAB can be 636 kg. This is almost 1/2 of the mass of the entire electric vehicle. The energy capacity of such a battery is 84.8 kWh, which is sufficient to overcome 800 km. In each case, a compromise between the battery capacity and weight must be chosen. The capacity of the TAB of a hybrid electric car can be selected from 5.3 to 12.72 kWh, depending on the desired run in the “only electricity” mode from 50 to 120 km. The capacity of the TAB of a hybrid vehicle can be selected from 1.06 to 5.3 kWh, depending on the desired run in the “only electricity” mode.

The problem. The article considers the problem of increasing the efficiency of the use of electric vehicles. This is done by studying and diagnosing electrical equipment of the BMW i3 electric car. Goal. The purpose of the work is to increase the efficiency of the use of electric vehicles by studying and diagnosing electrical equipment of BMW i3 elec-tric vehicle. Methodology. Systematic, theoretical analysis of the methods applied to an electric car. The methodology is based on the integrated approach to studying the BMW i3. The research of the main components of the electrical equipment of the electric vehicle was carried out, its technical characteristics and the principle of operation of the power system were analyzed, issues of charging a high-voltage battery were considered. System power control functions were investigated. The diagnostics of BMW i3 power system in the conditions of the service station was performed. Results. It is established that the purpose of the power control program is to provide sufficient level of the battery charge in different conditions of car operation. It is determined that for the BMW i3 you can use 4 different types of charging. It has been discovered that an emergency situation caused by a discharged battery or problems in the on-board power grid may have various causes, which in most cases do not relate to a high-voltage rechargeable battery. Originality. In the article a comprehensive study of the BMW i3 electric vehicle was conducted. Practical value. New original knowledge has been gained that will improve the performance of BMW i3 electric vehicle.

The large-radius exciton spectrum in a linear crystal with two atoms in the unit cell is obtained using the single-electron eigenfunctions and band structure found by the zero-range potentials method. The ground-state exciton binding energies for the linear crystal in vacuum turn out to be larger than the corresponding energy gaps for any set of the crystal parameters. [ABSTRACT FROM AUTHOR]

We describe the results of experimental investigation of the third-harmonic generation (THG) in β-BaB2O4 crystal pumped with a femtosecond laser radiation and cut at the angle θS permitting a process of direct phase-matched generation of oooe type. A theory of direct THG in uniaxial crystals, which assumes that the effective nonlinear coefficient has an additive nature with respect to the contributing processes, has been used when interpreting the experimental data. The angular dependence of the third harmonic intensity and its dependence on the incident pump power have been analysed in order to ascertain the process, the contribution of which is dominant. The analysis of our experimental results obtained under the condition of pumping β -BaB2O4 (θS = 53°) sample with femtosecond pulses (λ = 800 nm, τ = 70 fs, and Pmax = 100 GW/cm2) has proven that the contribution of second-order cascaded processes to the THG is prevailing. [ABSTRACT FROM AUTHOR]