Modelling of the coupling hydrodynamic transfer for a gas-liquid countercurrent flow on a wavy surface

This paper concerns laminar countercurrent gas–liquid flow over a wavy wall column, in the case of a falling liquid film. The modelling concerns the coupling of hydrodynamic and heat and mass transfer for an absorption as an example of application. The falling liquid film interacts, through the free interface, with the gas phase. The wavy surface generates particular hydrodynamic conditions with the presence of a vortex in both phases. The consequence of these vortices is an increase of transfers compared to the smooth wall

Effect of fingerprints orientation on skin vibrations during tactile exploration of textured surfaces

In humans, the tactile perception of fine textures is mediated by skin vibrations when scanning the surface with the fingertip. These vibrations are encoded by specific mechanoreceptors, Pacinian corpuscules (PCs), located about 2 mm below the skin surface. In a recent article, we performed experiments using a biomimetic sensor which suggest that fingerprints (epidermal ridges) may play an important role in shaping the subcutaneous stress vibrations in a way which facilitates their processing by the PC channel. Here we further test this hypothesis by directly recording the modulations of the fingerpad/substrate friction force induced by scanning an actual fingertip across a textured surface. When the fingerprints are oriented perpendicular to the scanning direction, the spectrum of these modulations shows a pronounced maximum around the frequency v/lambda, where v is the scanning velocity and lambda the fingerprints period. This simple biomechanical result confirms the relevance of our previous finding for human touch.Comment: Addendum to: Scheibert J, Leurent S, Prevost A, Debr\'egeas G. The role of fingerprints in the coding of tactile information probed with a biomimetic sensor. Science 2009; 323:1503?6 3 pages, 1 figur

Hydrodynamic and mass transfer efficiency of ceramic foam packing applied to distillation.

In addition to a high void volume and specific area, solid foams possess other properties (low density, good thermal, mechanical, electrical, and acoustical behaviour) that make them attractive for applications such as heat exchangers and reformers. Applications using foams as catalysts or structured catalyst supports have demonstrated higher performance than classical catalysts. Several studies have explored the hydrodynamic behaviour of foams in monophasic and counter current systems and have reported very low pressure drops. This paper describes the application of ceramic foam to distillation. The β-SiC foam contains 5 pores per inch (PPI) with a 91% void volume and a surface area of 640 m2/m3. Performance parameters including pressure drop for the dry and wet packing, flooding behaviour, and dynamic liquid hold-up were measured in a column of 150 mm internal diameter. The mass transfer efficiency in terms of the height equivalent to theoretical plate (HETP) was determined by total reflux experiments using a mixture of n-heptane and cyclohexane at atmospheric pressure. The experimental results were used to develop a set of correlations describing pressure drop and liquid hold-up in terms of a dimensionless number. The hydrodynamic performance and mass transfer efficiency were compared with classical packing materials used in distillation

Study of a laminar falling film flowing over a wavy wall column: Part II. Experimental validation of hydrodynamic model

The interface position of a film flowing over a wavy wall column is experimentally studied by an optical method composed of a charge coupled device (CCD) video camera. The results are compared with theoretical calculations and show a good agreement between results for both the film thickness and the vortex position. However, there exist some discrepancies because the interface is travelled by waves not accounted for in the mathematical model as it is supposed to be flat. Some characteristics of the waves are experimentally noted. Furthermore, the in¯uence of the viscosity on the film thickness is established as well

Nurses\u27 Alumnae Association Bulletin, April 1955

Alumnae Notes Annual Giving Committee Reports Digest of Alumnae Meetings Graduation Awards - 1954 Legal Aspects of Nursing Marriages Necrology New Arrivals Physical Advances at Jefferson President\u27s Message School of Nursing Report The Challenge of Neurosurgical Nursin

Wearing Two Hats: Anne Eggleston as Composer and Pedagogue

Canadian composer Anne Eggleston had an active career as both composer and piano pedagogue. In many of her works, such as Sketches of Ottawa, she sought to bridge the gap between these two interests. By examining the Anne Eggleston Fonds (MUS 282), acquired by Library and Archives Canada in 1997, we can begin to understand the personality of this remarkable composer and her commitment to piano pedagogy. Her teaching materials and her devotion to private students, as well as her affiliation with music organizations, paint a full picture of this important Canadian composer and pedagogue.Parallèlement à ses activités créatrices, la compositrice canadienne Anne Aggleston a mené une carrière active en pédagogie du piano. Plusieurs oeuvres, comme Sketches of Ottawa, tentent de combiner ces deux préoccupations. L’examen du Fonds Anne Eggleston (MUS 282), acquis par Bibliothèque et Archives Canada en 1997, aide à saisir la personnalité de cette compositrice remarquable et évaluer son engagement envers la pédagogie du piano. Ses notes de cours et son dévouement envers ses étudiants en privé, de même que son adhésion auprès d’organisations musicales, dessinent un riche portrait de cette importante compositrice et pédagogue