Electric-Line Milling Operation on Tree Master Valve of a High Surface Pressure Well Enables Well Control

2017 ◽  
Author(s):  
Mohammed D. Al-Ajmi ◽  
Raed A. Al-Ajlan ◽  
Nasser M. Al-Hajri ◽  
Hussain A. Al-Quwaisim ◽  
Saleh I. Zamka ◽  
...  
Keyword(s):  
Surface Pressure ◽  
High Surface ◽  
Well Control ◽  
Electric Line ◽  
Milling Operation ◽  
High Surface Pressure

Physicochemical Characterization of Tetraether Lipids from Thermoplasma acidophilum. II. Film Balance Studies on the Monomolecular Organization of the Main Glycophospholipid in Monofilms

1985 ◽  
Vol 40 (3-4) ◽  
pp. 219-222 ◽  
Author(s):  
Christoph Strobl ◽  
Lambert Six ◽  
Klaus Heckmann ◽  
Birgit Henkel ◽  
Klaus Ring
Keyword(s):  
Surface Pressure ◽  
High Surface ◽  
Physicochemical Characterization ◽  
Thermoplasma Acidophilum ◽  
Alkyl Chains ◽  
Head Groups ◽  
Air Water Interface ◽  
Tetraether Lipids ◽  
High Surface Pressure

The bipolar main tetraether lipid (MPL) of Thermoplasma acidophilum has been shown to form typical liquid expanded films at the air-water interface. The limiting molecular area at the collaps pressure is approximately Ac=73 Å2 per molecule. Monopolar aiphytanyl diether lipids were found to occupy the same area at high surface pressure as MPL. Thus, it was concluded that in the monofilm only one of the two polar headgroups of the MPL molecules is hydrated, i.e. that the single MPL molecules arc oriented upright. The packing properties of MPT. in the monofilm are determined by the properties of the branched alkyl chains only; the polar head groups do not contribute to the space requirement in the film. The collaps pressure of the MPL film is approximately 39 mN m-1 at 8°C. At a surface pressure of π = 30 mN m-1 and 20 °C the film is stable for many hours.

scholarly journals DPPC Monolayers Exhibit an Additional Phase Transition at High Surface Pressure

2015 ◽  
Vol 108 (2) ◽  
pp. 85a
Author(s):  
Chen Shen ◽  
Jorge B. de la Serna ◽  
Bernd Struth ◽  
Beate Klösgen
Keyword(s):  
Phase Transition ◽  
Surface Pressure ◽  
High Surface ◽  
High Surface Pressure ◽  
Additional Phase

scholarly journals Synoptically Driven Arctic Winter States

2011 ◽  
Vol 24 (6) ◽  
pp. 1747-1762 ◽  
Author(s):  
Kirstie Stramler ◽  
Anthony D. Del Genio ◽  
William B. Rossow
Keyword(s):  
Heat Conduction ◽  
Sea Ice ◽  
Surface Temperature ◽  
Surface Pressure ◽  
High Surface ◽  
The Arctic ◽  
Interface Temperature ◽  
Baroclinic Wave ◽  
Pressure Phase ◽  
High Surface Pressure

Abstract The dense network of the Surface Heat Budget of the Arctic (SHEBA) observations is used to assess relationships between winter surface and atmospheric variables as the SHEBA site came under the influence of cyclonic and anticyclonic atmospheric circulation systems. Two distinct and preferred states of subsurface, surface, atmosphere, and clouds occur during the SHEBA winter, extending from the oceanic mixed layer through the troposphere and preceded by same-sign variations in the stratosphere. These states are apparent in distributions of surface temperature, sensible heat and longwave radiation fluxes, ocean heat conduction, cloud-base height and temperature, and in the atmospheric humidity and temperature structure. Surface and atmosphere are in radiative–turbulent–conductive near-equilibrium during a warm opaquely cloudy-sky state, which persists up to 10 days and usually occurs during the low surface pressure phase of a baroclinic wave, although occasionally occurs during the high surface pressure phase because of low, scattered clouds. Clouds occurring in this state have near-unity emissivity and the lowest bases in the vicinity of, or below, the temperature inversion peak. A cold radiatively clear-sky state persists up to two weeks, and occurs only in the high surface pressure phase of a baroclinic wave. The radiatively clear state has clouds that are too tenuous when surface based or, irrespective of opacity, located too far aloft to contribute significantly to the surface energy budget. There is a 13-K surface temperature difference between the two states, and atmospheric inversion peak temperatures are linearly related to the surface temperature in both states. The snow–sea ice interface temperature oscillates over the course of the winter season, as it cools during the radiatively clear state and is warmed from atmospheric emission above and ocean heat conduction from below during the opaquely cloudy state. Analysis of satellite data over the Arctic from 70°–90°N indicates that the radiatively clear and opaquely cloudy states observed at SHEBA may be representative of the entire Arctic basin. The results suggest that model formulation inadequacies should be easier to diagnose if modeled energy transfers are compared with observations using process-based metrics that acknowledge the bimodal nature of the Arctic ocean–ice–snow–atmosphere column, rather than monthly and regionally averaged quantities. Climate change projections of thinner Arctic sea ice and larger advective water vapor influxes into the Arctic could yield different frequencies of occupation of the radiatively clear and opaquely cloudy states and higher wintertime temperatures of SHEBA ocean, ice, snow, atmosphere, and clouds—in particular, a wintertime warming of the snow–sea ice interface temperature.

CONTROLLED AGGREGATION OF AZOBENZENE BASED ON DNA-MIMETICS AT THE AIR–WATER INTERFACE

2002 ◽  
Vol 01 (05n06) ◽  
pp. 597-601 ◽  
Author(s):  
KUNIHARU IJIRO ◽  
JIN MATSUMOTO ◽  
MITSUHIKO MORISUE ◽  
MASATSUGU SHIMOMURA
Keyword(s):  
Free Volume ◽  
Surface Pressure ◽  
Base Pair ◽  
High Surface ◽  
Pair Formation ◽  
Water Interface ◽  
Air Water Interface ◽  
Pressure Area ◽  
Azobenzene Chromophore ◽  
High Surface Pressure

Monolayers of thymine amphiphile containing azobenzene chromophore (Azo-Thy) were prepared on various aqueous oligonucleotide ( dA 30, d(GA) 15, d(GGA) 10) subphases. Pressure–area isotherms and reflection absorption spectra of the monolayers on dA 30 or d(GA) 15 solution showed that the H-aggregate of the azobenzene units was formed at higher surface pressure than 25 mN/m . In contrast, the monolayer on an aqueous d(GGA) 10 solution did not form any aggregates of the azobenzene units even at high surface pressure. Base-pair formation between Azo-Thy and template d(GGA) 10 could give free volume to the azobenzene units in the monolayer to prevent the aggregation of the azobenzene units at the air–water interface.

scholarly journals Pressure sensing and control of an aircraft passenger seat

2021 ◽  
Author(s):  
Gabriel H. Campos
Keyword(s):  
Control System ◽  
Pressure Distribution ◽  
High Surface ◽  
Distribution Data ◽  
Pressure Sensing ◽  
Surface Change ◽  
Passenger Seat ◽  
Seat Comfort ◽  
And Control ◽  
High Surface Pressure

The premise of this work is to address aircraft seat comfort. This thesis presents the development of an automatic morphing backrest used to reduce pressure experienced by the passenger from the seat. Uncomfortable, high surface pressure zones on the backrest can be alleviated by decentralizing the occupant’s weight. The improved pressure distribution is intended to decrease discomfort during flight while taking different comfort/discomfort models into consideration. Pressure distribution data from the embedded sensor mat is used to compute the seat’s cushion deflection and corresponding backrest contour caused by the passenger’s weight. The surfaces of interest - the passenger’s back and the seat, are modelled and discretized. The discretized surface contact pressure is integrated into the hyperelastic contact model to determine the loading profile. From this, the current pressure distribution and the cushion’s surface change are computed and used in the control system to create the corresponding actuation of the surface.

scholarly journals Surface pressure retrieval from SCIAMACHY measurements in the O<sub>2</sub> A Band: validation of the measurements and sensitivity on aerosols

2005 ◽  
Vol 5 (8) ◽  
pp. 2109-2120 ◽  
Author(s):  
B. van Diedenhoven ◽  
O. P. Hasekamp ◽  
I. Aben
Keyword(s):  
Surface Pressure ◽  
Radiation Transport ◽  
High Surface ◽  
Transport Processes ◽  
Calibration Error ◽  
Systematic Bias ◽  
Free Oxygen ◽  
Meteorological Models ◽  
Insight Into

Abstract. We perform surface pressure retrievals from cloud-free Oxygen A band measurements of SCIAMACHY. These retrievals can be well validated because surface pressure is a quantity that is, in general, accurately known from meteorological models. Therefore, surface pressure retrievals and their validation provide important insight into the quality of the instrument calibration. Furthermore, they can provide insight into retrievals which are affected by similar radiation transport processes, for example the retrieval of total columns of H2O, CO, CO2 and CH4. In our retrieval aerosols are neglected. Using synthetic measurements, it is shown that for low to moderate surface albedos this leads to an underestimation of the retrieved surface pressures. For high surface albedos this generally leads to an overestimation of the retrieved surface pressures. The surface pressures retrieved from the SCIAMACHY measurements indeed show this dependence on surface albedo, when compared to the corresponding pressures from a meteorological database. However, an offset of about 20 hPa was found, which can not be caused by neglecting aerosols in the retrieval. The same offset was found when comparing the retrieved surface pressures to those retrieved from co-located GOME Oxygen A band measurements. This implies a calibration error in the SCIAMACHY measurements. By adding an offset of 0.86% of the continuum reflectance at 756 nm to the SCIAMACHY reflectance measurements, this systematic bias vanishes.

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