Equilibrated flow condition

In conclusion the dehydrogenation of butane has been studied over a Pt/alumina catalyst under continuous flow conditions. The system is operating at equilibrium in terms of total butene yield, however the 1-butene is does not undergo fast equilibration with the 2-butenes. The 2-butenes are usually in thermodynamic equilibrium. Analysis of the deactivation profiles of the butenes confirms that the carbon deposition reaction takes place on different sites for 1-butene and the 2-butenes. 

In these experiments, the glass surface is in the form of Pyrex tubing, treated extensively with chromic acid followed by distilled water and then equilibrated in the buffer to be used for adsorption. The experimental design is such that measurements can be done under either static or flow conditions. 

In H dialysis, mass transfer is executed under reproducible flow conditions which may be interrupted sometimes, but also in a reproducible manner. H on-line dialysis typically yield reproducibilities of 1-2% r.s.d. Although air-segmented continuous flow systems have also been used for on-line dialysis purposes, the introduction of air segments into the system defied the possibility of producing the highly reproducible conditions required for a non-equilibrated separation, and worse performances were obtained than those for non-segmented FLA systems. 

The flow rate of seawater is adjusted to 1.5-2.0L/min. The air flow (total air volume approximately 400 mL) is maintained at a flow rate of about l.OL/min. The time constant of this equilibrator with respect to CO2 is 75 6 s, as determined from laboratory experiments under the above flow conditions (Kortzinger et al., 1996). For measurements of seawater temperature, the equilibrator is equipped with a platinum resistance thermometer (Pt-100). 

Mobile phase Isocratic conditions aqueous 10% acetonitrile with 0.1% trifluoroacetic acid Flow 1 mL/min Gradient conditions phase A (acetonitrile water 1 9 pH to 2,5 with formic acid) phase B (acetonitrile water 3 7 pH to 2.5 with formic add) 0-30 min 10% B, 30.1-40.1 min 40% B, 10 min equilibration. Flow 0.7 mL/min... 

Conditioning Equilibrating a column with a flow of carrier gas (mobile phase) at the maximum expected operating temperature of the column. 

Gel Filtration. The lyophilized protein was redissolved in 50 mM phosphate buffer, pH 7.4 0.15 m NaCl 0.013 % sodium azide and loaded on a Superdex 75HR1030 column equilibrated with the same buffer. Elution was downward flow (0.15 ml/min) and 0.25 ml fi actions were collected. Fractions with pectin lyase activity were combined, dialyzed against distilled water and used in the next step. To estimate the molecular mass of PNL, the column was calibrated with standard proteins (Sigma MW-GF-70 Albumin, 66,000 Da Carbonic Anhidrase, 29,00 Cytochrome, 12,400 and Aprotinin, 6,500). The proteins were eluted in the conditions described above and their volumes (F ) were calculated fi om the peak maximum of the absorbance at 280 nm. The partition coefficient was obtained fi om the relationship where F, represents the bed volmne of column and F the void volume (which was calculated using blue dextran. Sigma). The molecular mass was determined using a standard curve of vs the logarithm of the molecular masses of the standards [28, 29]... 

Initial conditions 90 10 Linear gradient 30 70 in 7 min Re-equilibrate for approximately 3 min Divert flow to waste for approximately 3 min after injection 100... 

In TLC the stationary phase is pre-wet by volatile components in the mobile phase present in the vapour phase of the chromatographic chamber. The mobile phase is at the bottom of the developing chamber and advances on the stationary phase its movement depends on capillary forces. The stationary phase is equilibrated by the mobile phase front during its movement. Separations obtained under capillary flow controlled conditions are limited to a maximum of about 5000 theoretical plates. Forced-flow development requires an external force to move the mobile phase through the layer. 

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