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In chemical vapour deposition (CVD) reactants (as vapours) are induced to react or decompose chemically, leaving the desired material as a film on a substrate. The rates of some reactions may be increased in the presence of a plasma adjacent to the substrate. For more information see the wikipedia article about chemical vapour deposition.
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What is deposition in thermodynamics?
Deposition is the direct solidification of a vapor by cooling; the reverse of sublimation.
What is crude oil true vapor pressure?
True Vapor Pressure is the pressure of the vapor in equilibrium with the liquid at 100 F (it is equal to the bubble point pressure at 100 F)
What is the difference between gas power cycles and vapour power cycles?
Vapor-compression cycle(See Heat pump and refrigeration cycle and Vapor-compression refrigeration for more details)The vapor-compression cycle is used in most household refrigerators as well as in many large commercial and industrial refrigeration systems. Figure 1 provides a schematic diagram of the components of a typical vapor-compression refrigeration system.Figure 1: Vapor compression refrigerationThe thermodynamics of the cycle can be analyzed on a diagram[11][12] as shown in Figure 2. In this cycle, a circulating refrigerant such as Freon enters the compressor as a vapor. From point 1 to point 2, the vapor is compressed at constant entropy and exits the compressor as a vapor at a higher temperature, but still below the vapor pressure at that temperature. From point 2 to point 3 and on to point 4, the vapor travels through the condenser which cools the vapor until it starts condensing, and then condenses the vapor into a liquid by removing additional heat at constant pressure and temperature. Between points 4 and 5, the liquid refrigerant goes through the expansion valve (also called a throttle valve) where its pressure abruptly decreases, causing flash evaporation and auto-refrigeration of, typically, less than half of the liquid.Figure 2: Temperature-Entropy diagramThat results in a mixture of liquid and vapor at a lower temperature and pressure as shown at point 5. The cold liquid-vapor mixture then travels through the evaporator coil or tubes and is completely vaporized by cooling the warm air (from the space being refrigerated) being blown by a fan across the evaporator coil or tubes. The resulting refrigerant vapor returns to the compressor inlet at point 1 to complete the thermodynamic cycle.The above discussion is based on the ideal vapor-compression refrigeration cycle, and does not take into account real-world effects like frictional pressure drop in the system, slight thermodynamic irreversibility during the compression of the refrigerant vapor, or non-ideal gas behavior (if any).More information about the design and performance of vapor-compression refrigeration systems is available in the classic Perry's Chemical Engineers' Handbook.[13]Vapor absorption cycleMain article: Absorption refrigerator In the early years of the twentieth century, the vapor absorption cycle using water-ammonia systems was popular and widely used. After the development of the vapor compression cycle, the vapor absorption cycle lost much of its importance because of its low coefficient of performance (about one fifth of that of the vapor compression cycle). Today, the vapor absorption cycle is used mainly where fuel for heating is available but electricity is not, such as in recreational vehicles that carry LP gas. It is also used in industrial environments where plentiful waste heat overcomes its inefficiency.The absorption cycle is similar to the compression cycle, except for the method of raising the pressure of the refrigerant vapor. In the absorption system, the compressor is replaced by an absorber which dissolves the refrigerant in a suitable liquid, a liquid pump which raises the pressure and a generator which, on heat addition, drives off the refrigerant vapor from the high-pressure liquid. Some work is needed by the liquid pump but, for a given quantity of refrigerant, it is much smaller than needed by the compressor in the vapor compression cycle. In an absorption refrigerator, a suitable combination of refrigerant and absorbent is used. The most common combinations are ammonia (refrigerant) and water (absorbent), and water (refrigerant) and lithium bromide[absorbent].
What are factors affecting the reid vapor pressure of an oil?
The amount of light components in the oil affect the reid vapor vapor pressure. In petroleum products such as gasoline, the amount of butane in the gasoline blend has a strong affect on the Reid Vapor Pressure. To reduce RVP more stripping steam can be added to the product strippers. The fractionation in the debutanizer might also need to be adjusted to affect the RVP.
How do you convert Reid Vapor Pressure to True Vapor Pressure and vice versa?
http://www.epa.gov/ttn/chief/ap42/ch07/final/c07s01.pdf page 56
Which product is manufactured in the modified chemical vapor deposition MCVD process?
Optical Fibers
What is the process by which vapor directly converts into solid?
deposition
What has the author Brian E Williams written?
Brian E. Williams has written: 'Lightweight solar concentrator structures' -- subject(s): Chemical vapor deposition
What is chemical vapor deposition used for?
This is a chemical process used to make high purity and high quality solid materials. It is used frequently in the electronics industry and is also useful in making synthetic diamonds.
What is it called when vapor turns in to frost?
This process is called deposition.
What has the author Vithal Revankar written?
Vithal Revankar has written: 'Synthesis of high performance ceramic fibers by chemical vapor deposition for advanced metallics reinforcing' -- subject(s): Fiber-reinforced ceramics, Vapor-plating, Metallic composites
What is it called when water changes from a solid directly to a gas?
Water vapor that changes in to an ice crystal is called deposition. This what happens in the formation of snow.
The process by which water vapor changes directly to a solid is called?
deposition
What is the process by which water vapor changes directly to a solid is called?
Deposition
How the deposition formed?
Deposition is the process where matter changes from a gas to a solid. This occurs during cooling. When referrring the deposition as a weather process, water vapor forms into ice.
What has the author Jason Gilchrist written?
Jason Gilchrist has written: 'Semi-annual progress report on a study of reactive plasma deposited thin films' -- subject(s): Vapor deposition, Nitrides, Semiconductor devices, Thin films
What has the author F Plahutnik written?
F Plahutnik has written: 'Development of a polysilicon process based on chemical vapor deposition (phase 1 & phase 2)' -- subject(s): Silicon alloys
