We consider optical pumping with a quasi monochromatic tunable light beam, in the low intensity limit where a rate equation regime is obtained The velocity selective optical pumping (V.S.O.P.) introduces a correlation between atomic velocity and internal variables in the ground (or metastable) state. The aim of this article is to evaluate these atomic observables (orientation, alignment, popula...

PV array is increasingly employed for water pumping system. In this paper, the developed boost converter steps up the voltage produced by the PV array to a value which is suitable to run a single-phase induction motor. The inverter converts DC to AC is controlled by using sinusoidal pulse width modulation (SPWM) technique. By using a LCfilter the harmonics are eliminated and pure sine wave is o...

Froth is the basis to the extraction of bitumen from oil sand. Its components include sand, bitumen, water, and air. The technology of extraction and processing is evolving toward lower temperature of operation where the volumetric content of air and viscosity of bitumen challenge pumping. To improve the efficiency of froth handling pumps it is important to adapt the technology from other indus...

In mechanical studies of pumping a playground swing, two methods of energy insertion have been identified: parametric pumping and driven oscillation. While parametric pumping involves the systematic raising and lowering of the swinger's center of mass (CM) along the swing's radial axis (rope), driven oscillation may be conceived as rotation of the CM around a pivot point at a fixed distance to ...

Rhythmic movements are ubiquitous in animal locomotion, feeding, and circulatory systems. In some systems, the muscle itself generates rhythmic contractions. In others, rhythms are generated by the nervous system or by interactions between the nervous system and muscles. In the nematode Caenorhabditis elegans, feeding occurs via rhythmic contractions (pumping) of the pharynx, a neuromuscular fe...

ATP binding to the ϵ subunit of F1-ATPase, a soluble subcomplex of TFoF1 (FoF1-ATPase synthase from the thermophilic Bacillus strain PS3), affects the regulation of F1-ATPase activity by stabilizing the compact, ATPase-active, form of the ϵ subunit [Kato, S., Yoshida, M. and Kato-Yamada, Y. (2007) J. Biol. Chem. 282, 37618-37623]. In the present study, we report how ATP binding to the ϵ subunit...

Charge separation near a liquid/solid interface is explored by the electrohydrodynamic pumping of Freon TF, transformer oil, and silicone oil using high voltage traveling waves. Liquid head displacement measurements show strong dependencies on peak voltage amplitude (1.0-2.5 kV), frequency (0.1-20 Hz), liquid viscosity (0.5-20 cS), and liquid conductivity to 10-9 0-lm-l ). Reverse pumping, oppo...

Valveless pumping phenomena (peristalsis, Liebau-effect) can generate unidirectional fluid flow in periodically compressed tubular conduits. Early embryonic hearts are tubular conduits acting as valveless pumps. It is unclear whether such hearts work as peristaltic or Liebau-effect pumps. During the initial phase of its pumping activity, the originally straight embryonic heart is subjected to d...

Low pressure (,10s mTorr), high plasma density (.10 cm) reactors are rapidly becoming the tool of choice for etching during microelectronics fabrication. Although gas injection and pumping are well characterized process parameters in higher pressure systems, the impact of the symmetry of gas injection and pumping on the uniformity of reactant fluxes to the substrate are less well known in low p...

In complex hydrogeological environments the effective management of groundwater quality problems by pump-and-treat operations can be most confidently achieved if the mixing dynamics induced within the aquifer by pumping are well understood. The utility of isotopic environmental tracers (C-, H-, O-, S-stable isotopic analyses and age indicators-(14) C, (3) H) for this purpose is illustrated by t...