supercritical carbon dioxide (sc-co2) was used as solvent to synthesize oleyl oleate as an analog of jojoba oil from oleic acid and oleyl alcohol with high conversion (100%) of the acid into ester in a short time of 100 min. utilizing a low cost solid catalyst, p-toluenesulfonic acid monohydrate (ptsa), the esterification reaction was performed, without any prior preparation step, in a flow mod...

This thesis discusses particle production by supercritical antisolvent processing (SAS) techniques by looking the fundamentals and applications of the method with some case studies. The final aim of this work is however to consider the SAS particle production process feasibility. In the process studied the solid is dissolved in a conventional solvent and the solution is sprayed continuously thr...

A hydraulic jump is a sudden, rapid transition from a supercritical flow to a subcritical flow. At large inflow Froude numbers, the jump is characterized by a significant amount of entrained air. For this paper, the bubbly two-phase flow properties of steady and strong hydraulic jumps were investigated experimentally. The results demonstrate that the strong air entrainment rate and the depth-av...

We consider the behaviour of a continuous super-Brownian motion catalysed by a random medium with infinite overall density under the hydrodynamic scaling of mass, time, and space. We show that, in supercritical dimensions, the scaled process converges to a macroscopic heat flow, and the appropriately rescaled random fluctuations around this macroscopic ∗Supported by the DFG, EPSRC grant EP/C500...

Three vortex-generator configurations were installed aft of the inlet throat on the centerbody of a Mach 3 . 0 mixed-compression inlet. The three were about equal in im­ proving diffuser pressure recovery and all produced significant, although unequal, reduc­ tions in distortion. Only the most densely spaced configuration generated vortices that dissipated before reaching the compressor face. V...

A study was done as part of an effort to develop computational models representing turbulent mixing under thermodynamic supercritical (here, high pressure) conditions. The question was whether the large-eddy simulation (LES) approach, developed previously for atmospheric-pressure compressible-perfect-gas and incompressible flows, can be extended to real-gas non-ideal (including supercritical) f...

-In storm waterways and at dam outlets, high-velocity supercritical flows are characterized by substantial air bubble entrainment. The entrainment of fine air bubbles and the strong turbulent mixing contribute both to the air-water transfer of volatile gases (e.g. oxygen, nitrogen, VOC). The paper describes new experimental data obtained in a 25 m long channel with a 4 ° slope. The analysis of ...

Several test compounds were introduced into a unidirectional flow Ion mobillty spectrometer by both gas chromatography (GC) and supercritical fluld chromatography (SFC). The test samples were drugs from three general classes, opiates, benrodiazoplnones, and steroids. Drm spectra were collected for each compound by Fourier transform ion moblllty spectrometry. The drlft veioclty data for each com...

A depth-averaged 2-D model has been developed for simulating coastal barrier breaching processes. The model solves the generalized shallow water equations and the non-equilibrium sediment transport and bed change equations in a coupled fashion using an explicit finite volume method on a rectangular grid. It considers interactions among transient flow, strong sediment transport, and rapid bed ch...