На основі аналізу форми, ширини, енергетичного положення й інтегральної інтенсивності рентгенівських спектрів усіх серій, а також квантового виходу фотоемісії зроблено спробу пояснити природу ізотипізму силіцидів перехідних металів початку та кінця першого великого періоду.

Досліджено кути встановлення осей автомобілів-тягачів і напівпричепів. Визначено вплив перекосу осей на коефіцієнт опору кочення автопоїзда. Оцінено паливну економічність автопоїзда під час руху в режимі магістрального їздового циклу на дорозі за зміни коефіцієнта опору кочення. Доведено необхідність перевірки кутів встановлення мостів напівпричепа, як в процесі виготовлення, так і експлуатації автопоїздів.

Purpose. To improve both reliability and engineering accuracy of 3D modeling of a vehicle movement. Methodology. Orts of natural trihedral of spiral-helix supporting trajectory are expressed vectorially by means of time derivatives of a radius vector of a program movement. Quaternion matrices represent the complicated operations of vector algebra. Spatial orientation or program rotation of a natural trihedral is described with the help of Gibbs vector, Rodriguez-Hamilton vector, matrix of direction cosines depending upon kinematic parameters of the program movement. Findings. A hodograph of program transfer of a vehicle is represented in the class of spiral-helix supporting trajectories in terms of earth reference. Unit vectors of a natural trihedral of the spiral-helix supporting trajectory have been obtained depending on the time derivatives of the program motion hodograph. Originality. The program transfer - radius vector hodograph and program rotation (orientation) - Gibbs vector or quaternion on Rodriguez-Hamilton parameters are represented vectorially making it possible to model spatial orientation problems and problems of control of dynamic systems (i.e. vehicles) in the form of quaternion matrices. Practical value. Calculation formulas are represented in the ordered, compacted matrix form adapted directly to computer technology. The algorithm helps solve a wide range of problems of dynamic design of vehicles.

Purpose. Reliability and engineering precision improvement of 3D-modelling for kinematics and dynamics of ground transport vehicles. Criteria development for results verification. Methodology. Equivalent motive force of a high-speed vehicle of ground transport is determined based on program hodograph corresponding to spiral-screw trajectory. Motive force distribution is carried out for two supporting points of a ground transport vehicle. The problem is solved based on Varignon's theorem in a vector format, and it is considered in moving frame of reference of true trajectory trihedral. The formulated statistically undetermined problem is solved by involving design variable considering reactivity or inactivity of the supporting point. The verification of obtained analytical solution is carried out on the basis of kinetostatic invariants. Findings. The formulae are suggested for determining analytic contact forces in programmed motion of a high-speed vehicle of ground transport for tandem and parallel flow diagram of supporting points with respect to their reactivity or inactivity. The obtained formulae for contact forces comply with the first static invariant for the problem considered. The second static invariant enables determination of analytic dependences between the components of unknown contact forces, equivalent motive force, and geometric parameters. Originality. A method is suggested for statistically undetermined problem solution of equivalent motive force distribution for two contact points of a ground transport vehicle and the supportive surface. The method is based on the classical results of mechanics use: Varignon's theorem, static invariants, true trajectory trihedral of a ground transport vehicle. The formulated problem becomes resolvable in corpora by means of involving technically reasonable hypothesis of reactive-inactive links at the supporting point. Practical value. The obtained analytical solutions of formulated problem are informational, clear and convenient for analysis in engineering practice of dynamic development of high-speed ground transport vehicles. The calculation formulae are provided as properly arranged and adapted for machine-assisted realization. The method enables widening of resolvable problems range for dynamic development of ground transport vehicles of complex flow diagrams and any quantity of supporting points.