Search results for "gas transfer"
showing 4 items of 4 documents
Mechanical properties, internal structure and transport mechanism of oxygen in cork
2015
During the post bottling aging, premature oxidation reactions could occur and the oxygen barrier properties of the stopper are often pointed out. Nowadays, the internal structure of this material or the effect of hydration on its mechanical properties are still undetermined. Moreover, regarding the barrier properties, the limiting step of the oxygen transfer was not yet fully understood as well as the effect of compression or the role of the glass/cork interface in a bottleneck. The study of the internal structure of cork stopper allowed us to visualize the macroporosity of the material and conclude that there is no interconnectivity between lenticels, for the two qualities studied. The eff…
Microrheology of erythrocytes and platelets: physiological basis and consequences for the design and the operation of extracorporeal circulatory devi…
1976
Publisher Summary This chapter discusses the physiological basis and consequences for the design and the operation of extracorporeal circulatory devices. The microrheological response of erythrocytes and thrombocytes can be observed microscopically under simplified flow conditions in the rheoscope. In this device, cells are observed at high magnifications while being subjected to quantifiable shear stresses. Despite the unphysiological environment, the use of this method allowed an important extrapolation to well-established in vivo flow properties and a clear distinction between the primarily passive microrheological properties of the erythrocytes and the microrheological features of throm…
On the angular momentum transfer on to compact stars in binary systems
2001
Results of three-dimensional numerical simulations of the gas transfer in close binary systems show that, in addition to the formation of a tidally induced spiral shock wave, it is also possible for accretion streams to be produced, having low specific angular momentum in a region close to the accreting star. These streams are mainly placed above the orbital disc but are also unevenly present in the equatorial plane. The relevance of such flows is related to formation of hot coronae or bulges in regions very close to the accretor centre. The eventual formation of such bulges and shock-heated flows is interesting in the context of advection-dominated solutions and for the explanation of spec…
The anthropogenic sealing of soils in urban areas
2009
The sealing of soils by impervious materials is, normally, detrimental to its ecological functions. Exchanges of energy, water and gases are restricted or hampered and an increasing pressure is being exerted on adjacent, non sealed areas. The negative effects span from loss of plant production and natural habitats to increased floods, pollution, and health risks and consequently higher social costs. Environmental Agencies produce periodical reports where the phenomenon of soil consumption by urban infrastructures is monitored with extremely sophisticated geographical tools but little specific research is available that describes the effects of soil sealing. This paper reviews some recent co…