Laser studies in flames

Laser excited fluorescence was used to investigate minority species in premixed H₂:N₂:O₂ flames with temperatures ranging from about 1500 K to 2400 K. The species CH and NH were produced in a series of flames but detection by laser fluorescence failed. Fluorescence studies of metal atoms enabled the rate of spin-orbit relaxation Pb (7s³P₁°) → Pb (7s³P₀°) in collisions with atomic hydrogen and flame bulk-constituents to be measured. For hydrogen as the collision partner, the rate constant showed a negative temperature coefficient, varying as T⁻¹·⁷, whereas for other flame bulk constituents the rate constant showed a positive coefficient, varying as T¹·⁸. The process is described in terms of the Landau-Zener theory of non-adiabatic transitions between potential curves corresponding to excited states of the transient molecules formed during collisions. The magnitude of the rate constants and the signs of the temperature coefficients are predicted correctly by the application of the Landau-Zener theory

Анализ современных систем САПР с целью их использования для моделирования работы бурильной колонны в скважине

Nowadays, the assembly of laser systems is dominated by manual operations, involving elaborate alignment by means of adjustable mountings. From a competition perspective, the most challenging problem in laser source manufacturing is price pressure, a result of cost competition exerted mainly from Asia. From an economical point of view, an automated assembly of laser systems defines a better approach to produce more reliable units at lower cost. However, the step from todays manual solutions towards an automated assembly requires parallel developments regarding product design, automation equipment and assembly processes. This paper introduces briefly the idea of self-optimizing technical systems as a new approach towards highly flexible automation. Technically, the work focuses on the precision assembly of laser resonators, which is one of the final and most crucial assembly steps in terms of beam quality and laser power. The paper presents a new design approach for mini aturized laser systems and new automation concepts for a robot-based precision assembly, as well as passive and active alignment methods, which are based on a self-optimizing approach. Very promising results have already been achieved, considerably reducing the duration and complexity of the laser resonator assembly. These results as well as future development perspectives are discussed