Toward optimal DNA/RNA separation: High-vacuum thermal control of slalom chromatography columns.

Retention and efficiency of a novel slalom chromatography column: An alternative to agarose gel electrophoresis for DNA separation.

Retention mechanism in combined hydrodynamic and slalom chromatography for analyzing large nucleic acid biopolymers relevant to cell and gene therapies

Interfacial wave behavior and its effect on the flow and condensation heat transfer in a microtube

Retention mechanism in slalom chromatography: Perspectives on the characterization of large DNA and RNA biopolymers in cell and gene therapy.

Consequences of the radial heterogeneity of the column temperature at high mobile phase velocity

Ultra-high pressure slalom chromatography: Application to the characterization of large DNA and RNA samples relevant in cell and gene therapy

Theoretical predictions to facilitate the method development in slalom chromatography for the separation of large DNA molecules

Relationships are examined among radial eddy fluxes of heat, eddy temperature variances and basic-state temperature parameters (e.g., radial gradients and variances of the azimuthally averaged temperature) over a broad range of dimensionless parameters in thermally driven rotating annuli of fluid. We consider, first, changes of the time-averaged eddy heat flux and of the time and azimuthally averaged radial temperature gradient which take place when we conduct experiments at different imposed temperature differences With the rotation rate held fixed, or at different rotation rates with the imposed temperature difference held fixed. It is found that the observed changes of these variables cannot be described by a positive proportionality between the eddy heat flux and some positive power of the radial temperature gradient, except perhaps over limited ranges of dimensionless-parameter space. Within the regular wave regime, not too far from marginal stability, the eddy heat flux increases and the azimuthally averaged radial temperature gradient decreases with increasing rotation rate, when the imposed temperature contrast is held constant, suggesting that the effect of the eddies is to reduce substantially the magnitude of the temperature gradient. Evaluations are made also of the time variations of the eddy heat flux and of the azimuthally averaged radial temperature gradient at fixed points in dimensionless parameter space. The lag correlation function between these two variables is found to exhibit a unique characteristic which is common to all experiments. A lag correlation function calculated by Peter Stone using atmospheric data reveals a similar characteristic. The results suggest a new time-dependent parameterization of heat flux variations in terms of the basic-state temperature gradient.

Modelling the thermal behaviour of the Low-Thermal Mass Liquid Chromatography system

For the production of synthesis gas utilised in Midrex direct reduction plants, catalytic steam/CO2 hydrocarbon reforming in tubular reformer is the major process. Owing to the high heat input through the Midrex reformer tube wall, the endothermic nature of reforming reactions, low mass velocity of feed gas and large tube diameter, the catalyst bed is exposed to considerable axial and radial temperature gradients. These radial concentration and temperature gradients may create local areas with potential for carbon formation. To investigate this phenomenon, a rigorous two-dimensional model is developed for simulating the operation of a Midrex reformer which applies a dual catalyst loading profile. Both process side and furnace side have been included in this integrated model. Simulation results are in good agreement with available data from an actual plant. Using this model, a thermodynamic approach is applied to recognise zones in which the risk of carbon formation is high inside the reformer tubes. The results show that the first half of tubes, both in centre and near the wall, is critical from carbon forming point of view. Furthermore, the model shows that how a certain catalyst loading profile will affect the operation of the reformer.

In this paper, the temperature field of large-sized (120kg, 200kg and 300kg grade) sapphire single crystal furnace was simulated. By keeping the crucible diameter ratio and the insulation system unchanged, the power consumption, axial and radial temperature gradient, solid-liquid surface shape, stress distribution and melt flow were studied. The simulation results showed that with the increase of the single crystal furnace size, the power consumption increased, the temperature field insulation effect became worse, the growth stress value increased and the stress concentration phenomenon occurred. To solve these problems, the middle and bottom insulation system should be enhanced during designing the large-sized sapphire single crystal furnace. The appropriate radial and axial temperature gradient was favorable to reduce the crystal stress and prevent the occurrence of cracking. Expanding the interface between the seed and crystal was propitious to avoid the stress accumulation phenomenon.

Performance of a fixed-bed solid-state fermentation bioreactor with forced aeration for the production of hydrolases by Aspergillus awamori

Numerical simulation analysis, enabled by the physical vapor transport (PVT) technique, has been widely adopted to study the growth process of silicon carbide (SiC). In this study, a 2D axisymmetric model employed the finite volume method (FVM) is adopted to simulate the thermal fields and mass transfer of SiC powders with different particle sizes, thicknesses of the top thermal insulation, side wall thicknesses of the lid, and distances between the lid center and the top thermal insulation in a SiC crystal growth system. The simulation results revealed that the reduction in particle size increased the radial and axial temperature gradients in the powder region. Meanwhile, when the thickness of the top thermal insulation decreased, the axial temperature gradient inside the crucible increased significantly. Furthermore, the change in the side wall thickness of the lid significantly affected the thermal field distribution on the crystal surface and consequently affected the crystal growth shape. Finally, the variation in the distance between the lid center and the top thermal insulation has a significant influence on the axial and radial temperature gradients. Overall, these results indicate that the quality of SiC crystal growth may be improved by adjusting particle size, thermal insulation and crucible design.

Autothermal reactors with internal heat exchang—I Numerical and experimental studies in the multiple steady-state region

Two-and-three-dimensional analysis of Joule and viscous heating effects on MHD nanofluid forced convection in microchannels