High pressure gas lasers

Method. The laser vaporization source eliminates the material constraints inherent in conventional oven sources. This is accomplished by localizing the heating to a very small area at the surface of the sample and by entraining the vapor produced in a rapid flow of high pressure gas. 

Chemical Generation of High Temperature, High Pressure Gas for Laser Application , NOLTR-71-131 (1971) 28) N.M. Jardine ... 

A relatively unexplored extension of the Kramers theory is the escape of a Brownian particle out of a potential well in the presence of an external periodic force. Processes such as multiphoton dissociation and isomerization of molecules in high-pressure gas or in condensed phases/ laser-assisted desorption/ and transitions in current-driven Josephson junctions under the influence of microwaves " may be described with such a model, where the pieriodic force results from the radiation field. 

J.D. Weber, Handbook of Selected Properties of Air- and Water-Reacting Materials , RDTR 144(1969) 27)B.G.PaUay C.T. Zovko, Chemical Generation of High Temperature, High Pressure Gas for Laser Application , NOLTR-71-131 (1971) 28) N.M. Jardine ... 

CNTs find applications in the areas such as micro electronics, field emission displays. X-ray sources and gas sensors. Single waUed and multi-waUed CNTs can be grown using high pressure arcs, laser ablation and chemical vapour deposition. 

The efficiency of gas turbines is limited by the maximum allowable turbine inlet temperature (TIT). The TIT may be increased by cooling of the blades and vanes of the high pressure turbine. Cooling channels can be casted into the components or may be drilled afterwards. Non-conventional processes like EDM, ECD or Laser are used for drilling. Radiographic examination of the drilled components is part of the inspection procedure. Traditional X-Ray film technique has been used. The consumable costs, the waste disposal and the limited capacity of the two film units lead to the decision to investigate the alternative of Real-Time X-Ray. 

Since the demonstration by Schumacher et al ) of the use of alkali metal vapor inclusion into a supersonic beam to produce clusters, there have been a number of attempts to generalize the approach. It has recently been recognized that instead of high temperature ovens, with their concommitant set of complex experimental problems, an intense pulsed laser beam focused on a target could be effectively used to produce metal atoms in the throat of a supersonic expansion valve. ) If these atoms are injected into a high pressure inert gas, such as helium, nucleation to produce clusters occurs. This development has as its most important result that clusters of virtually any material now can be produced and studied with relative ease. 

The bombing test is use to check the tightness of components which are already hermetically sealed and which exhibit a gas-filled, internal cavity. The components to be examined (e.g. transistors, 1C housings, dry-reed relays, reed contact sw/itches, quartz oscillators, laser diodes and the like) are placed in a pressure vessel which is filled with helium. Operating with the test gas at relatively high pressure (5 to 10 bar) and leaving the system standing over several hours the test gas (helium) will collect inside the... 

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