Plasma separation process

The Energy Research and Development Agency (ERDA), the forerunner to the DOE, through the late 1970s to 1981 supported the study of three new experimental processes for uranium enrichment. Two were based upon laser separation, and one on plasma separation. Jersey Nuclear-Avco Isotopes Incorporated (subsidiary of Exxon) and the LLNL worked on atomic uranium vapor. LLNL referred to it as AVUS. The LANL and a group at Exxon Research Laboratories (not connected with Jersey-Avco) worked on molecular UFg. TRW Incorporated pursued research work on a plasma separation process. Union Carbide Nuclear Division (UCC-ND) supported each in their efforts. In 1981, the AVLIS process at LLNL was selected as the process to be developed further and the other processes were subsequently phased out. 

Plasmapheresis A process of separating blood cells from plasma. This process is used to remove monoclonal antibodies from the blood. 

Quaternary ammonium compounds may be actively secreted into the bile by a separate process. Compounds that undergo biliary excretion have been divided into classes A, B, and C. Class A compounds are excreted by diffusion and have a bile-to-plasma ratio of around 1 class B compounds are actively secreted into bile and have a bile-to-plasma ratio of greater than 1 and class C compounds are not excreted into bile and have a bile-to-plasma ratio of less than 1. The latter type of compound is usually macro molecules such as proteins or phospholipids. 

In principle, all powerful element-specific methods that are able to monitor continuously the effluents of separation processes commonly in the range of a few mimin-1 and in element concentrations of some Klpg liter-1. A well-suited method is based on modern element-specific quadrupole mass spectrometry (MS) with an inductively coupled plasma (ICP) interface to the separation unit [e.g., liquid chromatography (LC) or field-flow fractionation (FFF)].Tlie ICP-MS detection can also be used for continuously characterizing the effluent of any kind of packed column (Metreveli and Frimmel, 2007). By this, the transport and elution properties of... 

In order to find the domain of LCVD, it is necessary to compare various vacuum deposition processes chemical vapor deposition (CVD), physical vapor deposition (PVD), plasma chemical vapor deposition (PCVD), plasma-assisted CVD (PACVD), plasma-enhanced CVD (PECVD), and plasma polymerization (PP). All of these terms refer to methods or processes that yield the deposition of materials in a thin-film form in vacuum. There is no clear definition for these terms that can be used to separate processes that are represented by these terminologies. All involve the starting material in vapor phase and the product in the solid state. 

FPSA Fractioned plasma separation and adsorption is a very efficient and multifactorial method, employing membranes and adsor-bants. (86) It is additionally characterized by the use of microparticles (2.0-3.5 pm), which are recirculated in suspension using high-speed flow (2-4 1/min) to optimize the in-line filtration process. In a further development, a special sidfone filter is applied. 

Substrates are usually immersed in the plasmas in MW, DC and RF PACVD processes or separated from the plasmas in DC and RF thermal plasma CVD processes. A. substrate is generally placed 0.5-2 cm. fi-om the hot filament in the HFCVD, or fi om the flame burner nozzle in the combustion CVD, and up to 5 cm from the thermal plasma nozzle in the DC thermal plasma CVD.f " Report on distances greater than several centimeters has not been found in published literature, which may be attributable to... 

As the oceans of the world contain about 10 kg of deuterium and resources of lithium minerals are of comparable magnitude, it is clear that if this fusion reaction could be utilized in a practical nuclear reactor, the world s energy resources would be enormously increased. Although intensive research is being conducted on confinement of thermonuclear plasmas, it is not yet clear whether a practical and economic fusion reactor can be developed. If fusion does become practical, isotope separation processes for extracting deuterium from natural water and for concentrating from natural lithium will become of importance comparable to the separation of U from natural uranium. 

The non-equilibrium effect is much stronger than the equilibrium effect. Numerical values of the coefficient of selectivity for different plasma-chemical processes of isotope separation stimulated by vibrational excitation are presented in Fig. 3-13. A detailed consideration of the Treanor-effect isotope separation can be found in Akulintsev, Gorshunov, and Neschi-menko (1977,1983) for nitrogen and carbon monoxide isotopes and in Eletsky and Zaretsky (1981) and Margolin, Mishchenko, and Shmelev (1980) for hydrogen isotopes. 

This endothermic plasma-chemical process was considered, in particular, to be an important step in the thermochemical calcium-bromine-water splitting cycle for hydrogen production (Doctor, 2000). The plasma-chemical HBr decomposition (5-182) assumes in this case effective quenching and separation of products by fast rotation of quasi-thermal plasma... 

This endothermic plasma-chemical process was considered in Section 5.11.1. The process requires super-ideal quenching and separation of the products by fast plasma rotation similar to the case of plasma-chemical H2S dissociation (see Sections 10.7.5 and 10.7.6, and Fig. 5-76). The plasma-chemical stage (10-94), using off-peak electricity, can be a key step in the following HBr cycles of hydrogen production from water. The first cycle, proposed by Parker and Clapper (2001), applies the bromine produced in plasma (10-94) for reaction with water ... 

Matsuura, T. (1993), Synthetic Membranes and Membrane Separation Processes, CRC Press, Boca Raton, FL. Mattachini, E, Sani, E., Trebbi, G. (1996), Int. Workshop on Plasma Technologies for Pollution Control and Waste Treatment, MIT, Cambridge, MA. 

In 1979, Baadenhuijsen and Seuren-Jacobs [2] were the first to report on a FI gas diffusion separation system with a semi-permeable dimethylsilicone rubber membrane, used for the determination of carbon dioxide in plasma. In the same year. Zagatto et al.[3] introduced an isothermal distillation FI system in which ammonia diffused from a flowing donor liquid film across an air-gap and absorbed by a flowing acceptor film on the opposite side of the gap. However, later developments on gas diffusion separations mainly followed the approach of Baadenhuijsen and Seuren-Jacobs, obviously due to its simpler design and higher versatility. The first theoretical study on an FI gas-diffusion separation system was attempted by van der Linden [4], who used a tank-in-series model for the mathematical evaluation of the separation process. 

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