Regenerative

Bade P, Bourvier M and Coe J S 1987 Nd YLF mode-locked oscillator and regenerative amplifier Opt. Lett. 12 319-21... 

Vaillancourt G, Norris T B, Coe J S, Bade P and Mourou G 1990 Operation of a 1 kHz pulse-pumped Tfsapphire regenerative amplifier Opf. Lett. 15 317-19... 

Rudd J V, Korn G, Kane S, Squier J, Mourou G and Bade P 1993 Chirped-pulse amplification of 55 fs pulses at a 1 kHz repetition rate in a TIAI203 regenerative amplifier Opt. Lett. 18 2044-6... 

Norris T B 1992 Femtosecond pulse amplification at 250 kHz with a Ti sapphire regenerative amplifier and application to continuum generation Opt. Lett. 17 1009-11... 

Joo T, Jia Y and Fleming G R 1995 Ti sapphire regenerative amplifier for ultrashort high-power multikilohertz pulses without an external stretcher Opt. Lett. 20 389-91... 

Besides chemical catalytic reduction of carbon dioxide with hydrogen, which is already possible in the laboratory, we are exploring a new approach to recycling carbon dioxide into methyl alcohol or related oxygenates via aqueous eleetrocatalytic reduction using what can be called a regenerative fuel cell system. The direct methanol fuel cell... 

A regenerative fuel cell system can also be a single electrochemical cell in which both the oxidation of fuels (i.e., production of electric power) and reduction of CO2 (to obtain fuels) can be carried out by simply reversing the mode of operation. 

The appHcations of adsorbents are many and varied and may be classified as nonregenerative uses, in which the adsorbent is used once and discarded, and regenerative appHcations, in which the adsorbent is used repeatedly in a cycHc manner involving sequential adsorption and regeneration steps. 

W. E. Morrison and co-workers, "The Interior BaUistics of Regenerative Liquid Propellant Guns," Proceedings of 8th International Symposium on Ballistics, Apr. 1983. 

Most modem coke ovens operate on a regenerative heating cycle in order to obtain as much surplus gas as possible for use on the works, or for sale. If coke-oven gas is used for heating the ovens, the majority of the gas is surplus to requirements. If producer gas is used for heating, much of the coke-oven gas is surplus. 

Fig. 13. Cross-fined regenerative furnace (a) end view (b) side ...

Development of molybdenum electrodes in the 1950s permitted the use of electrically assisted melting in regenerative furnaces (81). In the 1990s, approximately one-half of all regenerative tanks ate electrically boosted. Operating practice has shown that effective use of electricity near the back end of the furnace, where the batch is added, can reduce fossil fuel needs. This lowers surface temperature and reduces batch volatilisation. 

Liver and Gallbladder. High dosages of oral estrogens have been reported to increase the risk for jaundice, cholestatic hepatitis, gallstones, and hepatic vein blood clots. Estrogens promote the development of hepatic neoplasms associated with increased hepatic cell regenerative activity (186,187). 

The electric discharge processes can supply the necessary energy very rapidly and convert more of the hydrocarbons to acetylene than in regenerative or partial combustion processes. The electric arc provides energy at a very high flux density so that the reaction time can be kept to a minimum (see... 

WulffProcess. The regenerative technique is best exemplified by the Wulff process, Hcensed by Union Carbide Corp. The furnace consists basically of two masses of high purity alumina refractory tile having cylindrical channels for gas flow and separated by a central combustion space as shown in Figure 10. Its cychc operation has four distinct steps, each of approximately 1 min in duration, the sequence being pyrolysis and heat in one direction followed by pyrolysis and heat in the other direction. Continuity of output is achieved by paired installations. 

The regenerative nature of the Wulff operation permits the recovery of most of the sensible heat in the cracked gas. The gases leave the furnace at temperatures below 425°C, thus obviating the need for special high temperature alloys in the switch valve and piping system. 

Regenerative pyrolysis processing is very versatile it can handle varied feedstocks and produce a range of ethylene to acetylene. The acetylene content of the cracked gases is high and this assists purification. On the other hand, the plant is relatively expensive and requires considerable maintenance because of the wear and tear on the refractory of cycHc operation. 

The unit Kureha operated at Nakoso to process 120,000 metric tons per year of naphtha produces a mix of acetylene and ethylene at a 1 1 ratio. Kureha s development work was directed toward producing ethylene from cmde oil. Their work showed that at extreme operating conditions, 2000°C and short residence time, appreciable acetylene production was possible. In the process, cmde oil or naphtha is sprayed with superheated steam into the specially designed reactor. The steam is superheated to 2000°C in refractory lined, pebble bed regenerative-type heaters. A pair of the heaters are used with countercurrent flows of combustion gas and steam to alternately heat the refractory and produce the superheated steam. In addition to the acetylene and ethylene products, the process produces a variety of by-products including pitch, tars, and oils rich in naphthalene. One of the important attributes of this type of reactor is its abiUty to produce variable quantities of ethylene as a coproduct by dropping the reaction temperature (20—22). 

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