Gas phase, continuous

Here, if Z is expressed in moles of collisions per square centimeter per second, r is in moles per square centimeter. We assume the condensation coefficient to be unity, that is, that all molecules that hit the surface stick to it. At very low Q values, F as given by Eq. XVII-3 is of the order expected just on the basis that the gas phase continues uniformly up to the surface so that the net surface concentration (e.g., F2 in Eq. XI-24) is essentially zero. This is the situation... 

If the packing surface is discontinuous in nature, a phase inversion occurs, and gas oubbles through the liquid. The column is not unstable and can be brought back to gas-phase continuous operation by merely reducing the gas rate. Analogously to the flooding condition, the pressure drop rises rapidly as phase inversion occurs. 

Catalytic tests were performed in a gas-phase continuous-flow reactor. The outlet flow of the reactor was either sampled for the analysis of the gaseous components, or condensed in a dry frozen trap, for the analysis of the solid and liquid products. Two liquid layers formed an organic layer containing the unconverted n-hexane, and an aqueous layer, some products dissolved preferentially in the organic layer, others in the aqueous one. Both layers were analyzed by gas chromatography. 

SCHEME 2.3 Gibbs energy profiles for the benzylation of NH3 (a), H20 (b), and H2S (c) by o-QM in the gas phase (continuous line), water-catalyzed (S4-S6) and uncatalyzed (S1-S3), and in aqueous solution (dotted line, Slaq-S6aq) optimizing both reagents and TSs in aqueous solution [B3LYP-C-PCM/6-311 +G(d,p)]. Data are taken from Ref. [13]. 

The steady state method is often used in continuous-flow operation with reaction, which is often the case in full-scale applications. In laboratory-scale investigations, the steady state method can be used with a semi-batch set-up (gas phase continuous) with reaction or a continuous-flow set-up (both gas and liquid phases continuous) with or without reaction. 

SAMPLE Condensed Phase Condensed Phase Gas Phase Continuous... 

In recent years these problems have been largely overcome with the development of gas-phase continuous back-mixed reactors like the Berty reactor. This reactor recirculates the gas... 

Electron transfer is usually carried out in bulk, condensed matter. In the gas phase, the lower concentrations of the donor and acceptor reduce the chance of an encounter between them in comparison with condensed phases. Furthermore, in the absence of a solvent, no stabilization of the separated ions by solvation is possible, enhancing the chance of charge recombination. The volume of published papers in this field is therefore much smaller for gaseous systems than for condensed matter. Nonetheless, gas-phase systems are in principle simpler to analyze and comparison with theory is more straightforward. The analysis of electron transfer in condensed systems usually starts from the (sometimes experimentally inaccessible) gaseous system. Therefore, efforts to study electron transfer in the gas phase continue, and have indeed shed much light on the mechanism of the process. 

The gas phase continuity and momentum equations are almost identical to those for the liquid phase, and are not repeated to save space. 

The indoor facility comprises a 20 x20 x40 thermally insulated enclosure that is continually flushed with purified air at a rate of 1000 L min and is located on the second floor of a laboratory building specifically designed to house it. Located directly under the enclosure on the first floor is an array of gas-phase continuous and semi-continuous gas-phase monitors. Within the enclosure are two 90 m (6.1 m x 3.1 m x 5.5 m, Siuface area to volume = 1.35 m ) 2 mil FEP Teflon film reactors, a 200 kW Argon arc lamp, a bank of 72 W 4-ft blacklights, along with the light and aerosol instrumentation. A schematic of the enclosure is provided in Figure 1. 

M. Ruta, I. Yuranov, P.J. Dyson, G. Laurenczy, L. Kiwi-Minsker, Structured fiber supports for ionic liquid-phase catalysis used in gas-phase continuous hydrogenation, J. Catal. 247 (2007) 269. 

A pseudo-homogeneous, two-dimensional reactor model for membrane reactors consists of the total gas-phase continuity and Navier-Stokes equations augmented with gas-phase component mass balances and the overall energy balance. 

When comparing with r = 0.124 s i, we can observe a difference due to the expansion of the gas-phase continuous system. 

The reactions of bare Fe" " ions and related species in the gas phase continue to attract much interest. The remote functionalisation of 1,6-hexanediol by Fe occurs by C-H activation at C(3) and C(4).26 Functionalisation of 3-methyl-2-pentanone at C(4) is diastereoselective, probably because of the conformation of a chair-like intermediate. Reactions of Fe with anisoles and phenols have also been studied.28 Interaction of Fe with silanes gives both silene and silylene species, though the two are not interconvertible. The reactions of Fe(alkene)+ complexes with pentane were found to differ dramatically from those of bare Fe" , and C-H and C-C activation were also observed in reactions of Fe(C2H4) with oxygen. 0,31 interaction of Fe(benzyne)+ with alkyl halides led to C-X or C-C addition followed by p-elimination and loss of HX.32 The gas phase reaction of Fe(NH2)Me" with C2H4 is best explained by insertion into the Fe-C bond followed by P-elimination and loss of propene. The reaction of FeMe with 1-octyne also leads to C-C bond forming processes. 

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