Evaporation Chamber

Additional ionization is effected by including radioactive substances or plasma or glow discharges in the evaporation chamber or by electrical charging of the nebulizer. Such techniques are also discussed in Chapters 8 and 11. 

Eventually, not only neutral solvent molecules but also ions start to desorb from the surface of each droplet, Ions, residual droplets, and vapor formed by electrospray are extracted through a small hole into two evaporation chambers (evacuated) via a nozzle and a skimmer, passing from there into the analyzer of the mass spectrometer, where a mass spectrum of the original sample is obtained. 

The flow of droplets enters an evaporation chamber that is heated sufficiently to prevent condensation. 

The mix of tiny drops is formed into a particle beam on passing through the exit nozzle of the evaporation chamber. 

FIG. 5. Schematic representation of the ASTER deposition system. Indicated are (I) load lock. (2) plasma reactor for intrinsic layers. (3) plasma reactor for />-type layers. (4) plasma reactor for t -type layers, (5) metal-evaporation chamber (see text). (6) central transport chamber. (7) robot arm. (8) reaction chamber, (9) gate valve, (10) gas supply. (11) bypass. (12) measuring devices, and (13) tur-bomolecular pump. 

A proposal is made to use a geothermal supply of hot water at 1500 kPa and 180°C to operate a steam turbine. The high-pressure water is throttled into a flash evaporator chamber, which forms liquid and vapor at a lower pressure of 400 kPa. The liquid is discarded while the saturated vapor feeds the turbine and exits at lOkPa. Cooling water is available at 15°C. Find the turbine power per unit geothermal hot-water mass flow rate. The turbine efficiency is 88%. Find the power produced by the geothermal power plant, and find the optimized flash pressure that will give the most turbine power per unit geothermal hot water mass flow rate. 

Ullrafine particles (UFPs) of metal and semiconductor nitrides have been synthesized by two major techniques one is the reactive gas condensation method, and the other is the chemical vapor condensation method. The former is modified from the so-called gas condensation method (or gas-evaporation method) (13), and a surrounding gas such as N2 or NII2 is used in the evaporation chamber instead of inert gases. Plasma generation has been widely adopted in order to enhance the nitridation in the particle formation process. The latter is based on the decomposition and the subsequent chemical reaction of metal chloride, carbonate, hydride, and organics used as raw materials in an appropriate reactive gas under an energetic environment formed mainly by thermal healing, radiofrequency (RF) plasma, and laser beam. Synthesis techniques are listed for every heal source for the reactive gas condensation method and for the chemical vapor condensation method in Tables 8.1.1 and 8.1.2, respectively. 

Tube evaporators may be designed as vertical tube evaporators (VTE) or horizontal tube evaporators (HTE). In the VTE. vapor produced in one effect is condensed in the next effect. The effect is an evaporator chamber receiving heat from an external source or from a higher effect and producing vapor and brine which may serve as a heat source for ihc next elfecl. To obtain high efficiency in the use of heal energy, the process is repeated in several evaporator effects arranged in series. Sec also Evaporation. 

An orifice with pressure drop Pc - Ph in which Pc is the vapor pressure in the evaporation chamber and P4 is the vapor pressure in the intermediate chamber, is sometimes referred to as a rate-controlling orifice. In a properly... 

Figure 8.9 Schematic of a sputter (left) and an evaporation chamber (right).

A schematic view of a web coater is shown in Fig. 8.5. The reel of film to be coated is placed in the upper part of the vacuum chamber, known as the winding chamber and, by means of suitable pumps, this chamber is evacuated to approximately 1 x 10-3 mbar. The winding chamber is separated from the lower part of the vacuum chamber, known as the evaporation chamber, by a differential pumping stage. 

Vacuum Contamination of the A1 layer by residual gas components (mainly water vapor) affects the barrier substantially good vacuum (<5 x 104 mbar) in the evaporation chamber is therefore required for barrier applications. Contamination from the evaporation material and the evaporators must also be avoided as much as possible. 

The reaction was studied in a laboratory assembled high-vacuum system (see Figures 9.8 and 9.9), consisting of two vacuum circuits, one for the evacuation of the evaporation chamber and the other for the evacuation of the gas introduction system [119,122,123], Figure 9.8 shows the fore pump, diffusion pumps, cold traps, ionization manometer, and the metal evaporation chamber [119]. The evaporation was carried out al / = 10 6 Torr, with the help of a thread helicoidal filament made of a wolfram (W) wire of 0.5mm diameter and 10cm length [119]. The whole vacuum system was coupled with a mass spectrometer, Hitachi RMU-6D, in order to follow the reaction kinetics [119,122,123] (see Figure 9.9). The procedures followed in order to study the reaction were as follows ... 

Fe was evaporated in the center of a 5 L spherical Pyrex glass container, connected to the vacuum system (shown in Figure 9.8), whose walls were covered with a fresh iron surface (this container was enclosed in a furnace to control the reaction temperature). Then, NO from the sample introduction system was introduced into the evaporation chamber and the reaction followed at different temperatures, with the help of the mass spectrometer [119]. 

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