Gotowe bibliografie tematyczne / Pressures

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Gotowa bibliografia na temat „Pressures”

Autor: Grafiati

Data publikacji: 4 czerwca 2021

Data aktualizacji: 31 stycznia 2023

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Artykuły w czasopismach na temat "Pressures"

Kindgen-Milles, D., A. Gabriel, R. Buhl, H. Böhner i E. Müller. "Nasal continuous positive airway pressure: do mask pressures reliably reflect intratracheal pressures?" Critical Care 3, Suppl 1 (1999): P021. http://dx.doi.org/10.1186/cc396.

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Zhou, Yang, Shuanghui Hao i Minghui Hao. "A two-dimensional numerical analysis of a circular-arc gear pump operating at high pressures and high speeds". Proceedings of the Institution of Mechanical Engineers, Part E: Journal of Process Mechanical Engineering 231, nr 3 (27.08.2015): 432–43. http://dx.doi.org/10.1177/0954408915602625.

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This paper examines the flow field of a circular-arc gear pump operating at high pressures and high speeds by the commercial finite-volume-based code Fluent. The performance of circular-arc gear pump operating at high pressures and high speeds have been discussed. The mathematical model of the tooth profile is established. The pressures including gears mesh, outlet pressures, and outlet flow rate are studied under different rated outlet pressures and rotational speeds. There are dynamic pressures at clearance between chamber and tip circle of gear. Moreover, parts of radial leakages are prevented by dynamic pressures. The outlet pressures almost remain constant. However, there are strong pressure fluctuations in gears mesh under the high pressures and high speeds. The pressures are several times higher than the rated outlet pressure when the circular-arc gear pump operates at 10,000 r/min and 12,000 r/min. Gear meshing pressure fluctuations increase with the increase in rotational speeds. However, gear meshing pressure fluctuations decrease with the increase of outlet rate pressures. There are rotational speeds and outlet rate pressure critical points for gear meshing pressures, and the variation tendency of gear meshing pressures changes dramatically when it exceeds the critical points. Hence, the research results provide base model for circular-arc gear pump operating at high pressures and high speeds.

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Glucksberg, M. R., i J. Bhattacharya. "Effect of alveolar and pleural pressures on interstitial pressures in isolated dog lungs". Journal of Applied Physiology 70, nr 2 (1.02.1991): 914–18. http://dx.doi.org/10.1152/jappl.1991.70.2.914.

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We report the first direct measurements of perialveolar interstitial pressures in lungs inflated with negative pleural pressure. In eight experiments, we varied surrounding (pleural) pressure in a dog lung lobe to maintain constant inflation with either positive alveolar and ambient atmospheric pleural pressures (positive inflation) or ambient atmospheric alveolar and negative pleural pressures (negative inflation). Throughout, vascular pressure was approximately 4 cmH2O above pleural pressure. By the micropuncture servo-null technique we recorded interstitial pressures at alveolar junctions (Pjct) and in the perimicrovascular adventitia (Padv). At transpulmonary pressure of 7 cmH2O (n = 4), the difference of Pjct and Pady from pleural pressure of 0.9 +/- 0.4 and -1.1 +/- 0.2 cmH2O, respectively, during positive inflation did not significantly change (P less than 0.05) after negative inflation. After increase of transpulmonary pressure from 7 to 15 cmH2O (n = 4), the decrease of Pjct by 3.3 +/- 0.3 cmH2O and Pady by 2.0 +/- 0.4 cmH2O during positive inflation did not change during negative inflation. The Pjct-Pady gradient was not affected by the mode of inflation. Our measurements indicate that, in lung, when all pressures are referred to pleural or alveolar pressure, the mode of inflation does not affect perialveolar interstitial pressures.

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Gravlee, G. P., S. D. Brauer, M. F. O'Rourke i A. P. Avolio. "A Comparison of Brachial, Femoral, and Aortic Intra-Arterial Pressures before and after Cardiopulmonary Bypass". Anaesthesia and Intensive Care 17, nr 3 (sierpień 1989): 305–11. http://dx.doi.org/10.1177/0310057x8901700311.

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Following recent evidence that brachial and femoral artery pressures are more reliable than radial artery pressures after cardiopulmonary bypass, thirty-one adults had simultaneous pre and post-bypass measurements of brachial, femoral, and ascending aortic pressures. Two minutes after cardiopulmonary bypass, brachial artery systolic pressure and mean arterial pressure fell significantly below corresponding pressures in the femoral artery and aorta. Five minutes after cardiopulmonary bypass, only brachial artery systolic pressure was still less than femoral and aortic systolic pressures. By ten minutes after bypass, all significant pressure differences had resolved except between brachial and femoral artery systolic pressures. Clinically significant (≥ 5 mmHg) aortic-to-brachial reductions in mean arterial pressures occurred in six (19%) patients at two minutes and in three (10%) patients at five and ten minutes after bypass. Equivalent aortic-to-femoral mean pressure diminution occurred in two (6%) patients at two minutes and one (3%) patient at five and ten minutes after bypass. Neither systemic vascular resistance nor body temperatures contributed significantly to post-bypass central-to-peripheral pressure reductions. Immediately following bypass, femoral artery pressures reproduce central aortic pressures more reliably than do radial or brachial artery pressures.

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Mendelowitz, D., i A. M. Scher. "Pulsatile pressure can prevent rapid baroreflex resetting". American Journal of Physiology-Heart and Circulatory Physiology 258, nr 1 (1.01.1990): H92—H100. http://dx.doi.org/10.1152/ajpheart.1990.258.1.h92.

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In a previous study [Am. J. Physiol. 255 (Heart Circ. Physiol. 24): H673-H678, 1988] we demonstrated that baroreflex responses decay (reset) to increased static sinus pressures, but with increased pulsatile pressure, responses are maintained. To determine more conclusively whether pulsatile pressure prevents rapid baroreflex resetting in this study we examined resetting as shifts of the baroreflex (sinus pressure-arterial pressure) curve. In seven anesthesized rabbits the left sinus was vascularly isolated and conditioned for 5 min to static or pulsatile pressures of 60, 100, or 140 mmHg mean pressure, 0 or 35–40 mmHg pulse pressure. The baroreflex curve was then determined by stepwise changing sinus pressure from 40 to 160 mmHg in 20-mmHg increments. Threshold, midpoint, and saturation sinus pressures shifted 25-39% with static conditioning pressures but did not shift significantly with pulsatile pressures. Also, the baroreflex responses to step increases in static sinus pressure decayed, as resetting occurred, but did not decay with pulsatile sinus pressure increases. Thus the baroreflex rapidly resets with static pressures, but there is minimal, if any, resetting with pulsatile pressures.

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Fixler, David E., W. Pennock Laird i Kent Dana. "Usefulness of Exercise Stress Testing for Prediction of Blood Pressure Trends". Pediatrics 75, nr 6 (1.06.1985): 1071–75. http://dx.doi.org/10.1542/peds.75.6.1071.

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The purpose of this study was to determine whether values of blood pressure during exercise help predict which adolescents are prone to maintain high blood pressure. Dynamic and isometric exercise stress tests were performed on 131 adolescents who had had systolic or diastolic pressures greater than the 95th percentile on three examinations the previous year. Follow-up blood pressures were measured 1 year after the stress testing, and outcomes were classified on the basis of the blood pressure status that year. Stepwise regression analysis was used to examine the association between earlier blood pressures and exercise pressures with outcome pressures. In both male and female adolescents, the average resting systolic pressure on the earlier survey was the best predictor of systolic pressure 2 years later. Blood pressures and heart rates during dynamic and isometric exercise did not significantly contribute to the models' prediction of future systolic or diastolic pressures. The data suggest that exercise stress testing is not a valid method for predicting youths whose blood pressures will remain elevated over the next 1 to 2 years.

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Fike, C. D., i S. J. Lai-Fook. "Effect of airway and left atrial pressures on microcirculation of newborn lungs". Journal of Applied Physiology 69, nr 3 (1.09.1990): 1063–72. http://dx.doi.org/10.1152/jappl.1990.69.3.1063.

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To determine the effect of lung inflation and left atrial pressure on the hydrostatic pressure gradient for fluid flux across 20- to 60-microns-diam venules, we isolated and perfused the lungs from newborn rabbits, 7-14 days old. We used the micropuncture technique to measure venular pressures in some lungs and perivenular interstitial pressures in other lungs. For all lungs, we first measured venular or interstitial pressures at a constant airway pressure of 5 or 15 cmH2O with left atrial pressure greater than airway pressure (zone 3). For most lungs, we continued to measure venular or interstitial pressures as we lowered left atrial pressure below airway pressure (zone 2). Next, we inflated some lungs to whichever airway pressure had not been previously used, either 5 or 15 cmH2O, and repeated venular or interstitial pressures under one or both zonal conditions. We found that at constant blood flow a reduction of left atrial pressure below airway pressure always resulted in a reduction in venular pressure at both 5 and 15 cmH2O airway pressures. This suggests that the site of flow limitation in zone 2 was located upstream of venules. When left atrial pressure was constant relative to airway pressure, the transvascular gradient (venular-interstitial pressures) was greater at 15 cmH2O airway pressure than at 5 cmH2O airway pressure. These findings suggest that in newborn lungs edema formation would increase at high airway pressures only if left atrial pressure is elevated above airway pressure to maintain zone 3 conditions.

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VERSI, E., LINDA CARDOZO i D. J. COOPER. "Urethral Pressures: Analysis of Transmission Pressure Ratios". British Journal of Urology 68, nr 3 (wrzesień 1991): 266–70. http://dx.doi.org/10.1111/j.1464-410x.1991.tb15320.x.

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Dunstan, D. J., N. W. A. Van Uden i G. J. Ackland. "High Pressure Instrumentation: Low and Negative Pressures". High Pressure Research 22, nr 3-4 (styczeń 2002): 773–78. http://dx.doi.org/10.1080/08957950212441.

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Ruth, P. J. van, R. R. Hillis i R. E. Swarbrick. "DETECTING OVERPRESSURE USING POROSITY-BASED TECHNIQUES IN THE CARNARVON BASIN, AUSTRALIA". APPEA Journal 42, nr 1 (2002): 559. http://dx.doi.org/10.1071/aj01032.

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Overpressure has been encountered in many wells drilled in the Carnarvon Basin. Sonic logs are used to estimate pore pressure in shales in the Carnarvon Basin using the Eaton and equivalent depth methods of estimating pore pressure from velocity data with reference to a normal compaction trend. The crux of pore pressure estimation from the sonic log lies in the determination of the normal compaction trend, i.e. the acoustic travel time (Δt)/depth (z) trend for normally pressured sediments. The normal compaction trend for shales in the Carnarvon Basin was established by fitting an Athy-type exponential relationship to edited sonic log data, and is: Δt = 225 + 391exp(-0.00103z) Vertical stress estimates are also needed for the Eaton and equivalent depth methods used herein. A vertical stress (σv) relationship was obtained by fitting a regression line to vertical stress estimates from the density log, and is: σv = 0.0131 z1.0642 The Eaton and equivalent depth methods yield similar pressure estimates. However, the equivalent depth method can only be applied over a limited range of acoustic travel times, a limitation that does not apply to the Eaton method. The pressure estimates from the Eaton method were compared to pressures measured by direct pressure tests in adjacent permeable units. There is a good correlation between Eaton and test pressures in normally pressured intervals in three wells and overpressured intervals in two wells. Eaton pressure estimates underestimate overpressured direct pressure measurements in four wells by up to 13 MPa. This is consistent with overpressure being generated (at least in part) by a fluid expansion mechanism or lateral transfer of overpressure. The Eaton pressures in one well are, on average, 11 MPa lower than hydrostatic pore pressure recorded in direct pressure measurements below the Muderong Shale. The sediments in this well appear to be overcompacted due to exhumation. Mud weights can be used as a proxy for pore pressure in shales where direct pressure measurements are not available in the adjacent sandstones. The Eaton pressure estimates are consistent with mud weight in the Gearle Siltstone and Muderong Shale in 4 of the 8 wells studied. The Eaton pressures are on average 10 Mpa in excess of mud weight in the Muderong Shale and Gearle Siltstone in three wells. It is unclear whether the predicted Eaton pressures in these three wells accurately reflect pore pressure (i.e. the mud weights do not accurately reflect pore pressure), or whether they are influenced by changes in shale mineralogy (because the gamma ray filter does not differentiate between shale mineralogy).

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Rozprawy doktorskie na temat "Pressures"

Lim, C. S. "Plastic limit pressures for pressure vessels with defects at openings". Thesis, Cardiff University, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.234339.

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Quin, David John Gilbert. "Bridging the pressure gap : taking surface science to more realistic pressures". Thesis, University of Southampton, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.484956.

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Traditional surface science experiments are conducted under ultra high vacuum conditions, this enables surface cleanliness to be strictly controlled and the use of electron based measurements, to determine surface structure and composition. Unfortunately, lftlV conditions are very different from those in real world catalysis (e.g. car exhaust clean-up) and only limited insight can be obtained from such studies. For example, it has been found that certain catalytic species do not exist under UHV conditions. It is an essential step in the progression of surface science to move to more realistic conditions whilst still retaining the simplicity enabled by a UHV cleaned, ideal surface such as a single crystal. this thesis the development of two new pieces of equipment, which bridge this gap, at the SRS at Daresbury Laboratory are presented. The High Pressure Reaction Cell (HPRC), based on the far-IR beamline 13.3 at Daresbury laboratory, enables samples to be cleaned under lJHV conditions before being exposed to pressures, inside the cell, of up to 200 mbar of a chosen gas, without compromising the external vacuum. Far-IR RAIRS, which is useful for adsorbate investigations, is unaffected by the presence of a partial pressure of gas, enabling in-situ measurements as well as postexperiment UHV measurements. Results are presented for investigations into the high pressure oxidation and reduction copper, these are supported by DFT calculations ofthe phonon modes for common copper oxides. The High Ambient Pressure Photoelectron spectroscopY (H.APPY) system is a peripatetic end station designed to allow sample cleaning in UHV, before performing in-situ photoelectron spectroscopy at pressures up to 10-2 mbar. The commissioning experiments in which a commercial supported catalyst was studied are presented. The future of these two newly developed pieces of equipment is discussed alongside the future offar-IR RAIRS as a whole.

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Watts, Travis James. "DIRECT MEASUREMENT OF CROSSTIE-BALLAST INTERFACE PRESSURES USING GRANULAR MATERIAL PRESSURE CELLS". UKnowledge, 2018. https://uknowledge.uky.edu/ce_etds/74.

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The magnitudes and relative pressure distributions transmitted to the crosstie-ballast interface of railroad track significantly influences the subsequent behavior and performance of the overall track structure. If the track structure is not properly designed to distribute the heavy-axle loads of freight cars and locomotives, deficiencies and inherent failures of the crossties, ballast, or underlying support layers can occur, requiring substantial and frequent maintenance activities to achieve requisite track geometrical standards. Incorporating an understanding of the pressure distribution at the crosstie-ballast interface, appropriate designs can be applied to adequately provide a high performing and long-lasting railroad track. Although this can be considered a simple concept, the magnitudes and distributions of pressures at the crosstie-ballast interface have historically proven to be difficult to quantifiably measure and assess over the years. This document describes the development and application of a method to measure average railroad track crosstie-ballast interfacial pressures using timber crossties and pressure cells specifically designed for granular materials. A procedure was specifically developed for recessing the cells in the bottoms of timber crossties. The validity of the test method was initially verified with a series of laboratory tests. These tests used controlled loads applied to sections of trackbed constructed in specifically designed resilient frames. The prototype trackbed section was intended to simulate typical in-track loading conditions and ballast response. Cells were subsequently installed at a test site on an NS Railway well-maintained mainline just east of Knoxville, TN. Six successive crossties were fitted with pressure cells at the ballast interface below the rail seat. Pressure cells were also installed at the center of two crossties where the ballast is typically not tamped or consolidated. Trackbed pressures at the crosstie-ballast interface were periodically measured for numerous revenue freight trains during a period of twenty-one months. After raising and surfacing the track, the ballast was permitted to further consolidate under normal train traffic before again measuring pressures. Having the ballast tightly and uniformly compacted under crossties is important to ensuring representative and reproducible pressure measurements. Measured maximum pressures under the rail at the crosstie-ballast interface ranged from 20 to 30 psi (140 to 210 kPa) for locomotives and loaded freight cars with smooth wheels producing negligible wheel/rail impacts. Crosstie-ballast interface pressures were typically 3 psi (20 kPa) maximum for empty freight cars with smooth wheels. Heavily loaded articulated intermodal car pressures for shared trucks tended to reach nearly 40 psi (280 kPa), actually higher than locomotive-produced pressures. The recorded pressures under the center of the ties were normally negligible, less than 1 psi (7 kPa) for locomotives and loaded freight cars. Wheel-Rail force parameters measured by nearby wheel-impact load detectors (WILD) were compared to crosstie-ballast pressure data for the same trains traversing the test site. Increases in peak WILD forces, either due to heavier wheel loads or increased impacts, were determined to relate favorably to increases in recorded trackbed pressures with a power relationship. The ratios between the peak and nominal wheel forces and trackbed pressures also have strong relationships.

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Svensson, Stefan. "Micropumps for extreme pressures". Thesis, Uppsala University, Micro Structural Technology, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-110880.

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The objective of this thesis was to improve a paraffin actuated micropump design, to be able to pump against extreme pressures (above 100 bar). This was accomplished by initially studying the membrane activation, using video capturing. The micropump has been improved to withstand pressures high enough, to enable use in an high-performance liquid chromatography (HPLC) system. The micropump has been shown to pump against back pressures up to 150 bar, with a positive net-flow. This should be compared with the previously recorded maximum back pressure of 50 bar. The pumping against high back pressures was possible due to an increased understanding of the sealing of the membranes. This resulted in a new design that was manufactured and characterised. Without clamping the pump was measured to manage back pressures of 10 bar, and then starting to leak in a bond at the flow channel. With supporting clamping, the managed back pressures increased ten folded.

When measured on the different valves, pressure above 200 bar has been possible to withhold. Although the valves were below their maximum limit, the pressure was not possible to be further increased due to a limitation in the equipment, i.e. risk of damaging the connections. When examined after pressurised at extreme pressures (above 100 bar) several times, no signs of fatigue or damage of the membrane was seen.

A new behaviour of the valves was discovered. Above certain pressures some designs self sealed, i.e. withholding the pressure after the voltage was turned off. For these valves the pressure had to be released by some other means.

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Kowal, Daniel Joseph. "Pressures experienced by adolescents". Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/25432.

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The purpose of this study was to examine the types of pressures adolescents experience. The factors of age and/or gender were also investigated in order to determine any possible effects upon adolescent experienced pressures. The researcher believed that findings from such a study could be useful to high school counsellors in both planning future Guidance programs for adolescents as well as aiding in individual counselling sessions with their adolescent clients. Using a cluster-sampling technique, 505 adolescents were selected from a Vancouver high school. Subjects were chosen with consideration to the factors of age and gender. The researcher designed an open-form measurement instrument intended to gather adolescent responses to the three greatest pressures they had experienced during the previous four months. Following a pilot of the instrument, which was to aid in determining construct validity, the survey was administered to the sample over an eight day testing period. With the initial help of an assistant, responses were content analyzed and initial categories constructed. All responses were coded and assigned a frequency score to one of eleven mutually exclusive categories. The chi-square "Goodness of Fit" test for significant difference between or among groups was then applied. Results of the statistical analysis indicated that the factors of age and/or gender are related to certain types of pressures experienced by adolescents. Future Pressure was found to be a significant pressure experienced by older age adolescents. Regardless of gender, age appears to be an important factor related to who will experience Future Pressure. Female adolescents experience greater Family Pressure than do males. Whether within the same age group or within a total female and. a total male population comparison, this result remains consistent. Younger age adolescents also indicate greater gender differences compared with older age adolescents. Younger age female adolescents are more likely to experience greater Family Pressure and Peer Pressure while young male adolescents are more likely to experience greater Situational Pressure. In conclusion, it appears that significant gender differences found in this study tend to support the notion that differences in the rate of physical growth as well as learned sexual stereotypes are significant factors in determining such differences.
Education, Faculty of
Educational and Counselling Psychology, and Special Education (ECPS), Department of
Graduate

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Tissot, Héloïse. "Beyond the gap of pressure : XPS studies of interfaces at near ambient pressures". Thesis, Paris 6, 2014. http://www.theses.fr/2014PA066615/document.

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Dans de nombreux procédés technologiques, tels que la fabrication de matériaux pour la microélectronique, l’étude des réactions chimiques à une électrode, ou encore la catalyse… L’interface entre la surface d’un solide ou d’un liquide avec un liquide ou une phase gaz joue un rôle fondamental. De façon analogue, les sciences de l’environnement ainsi que celles du vivant intègrent dans leurs modèles la réactivité aux interfaces solide/ liquide ou liquide/ gaz.L’XPS est une technique parfaitement adaptée à l’étude des interfaces et a été largement utilisée pour l’analyse des surfaces de solides. Le principal avantage de l’XPS est sa grande sensibilité aux surfaces. En effet, en raison du faible libre parcours moyen des électrons dans un solide, uniquement les photoélectrons provenant de l’extrême surface (1 – 10 nm) peuvent échapper à celle-ci. Cependant, l’XPS est traditionnellement utilisée dans des conditions d’ultravide (UHV) et cela pour deux raisons. La première est que les analyseurs d’électrons sont construits pour fonctionner en UHV. La seconde est que les électrons doivent pouvoir atteindre l’analyseur, or leur libre parcours moyen est faible dans un gaz à haute pression. Par exemple, à une pression de 1 mbar, des électrons possédant une énergie de 100 eV vont parcourir 1 mm alors qu’ en UHV ils pourront atteindre jusqu’ à 105 m.Dans le but de rendre possible l’utilisation de l’XPS à des pressions plus élevées, quelques groupes autour du monde, dont le groupe de Berkeley (sous la direction de M. Salmeron at de H. Bluhm) et celui du Fritz Haber Institute à Berlin, ont élaborés un équipement permettant d’atteindre des pressions proche de l’ambiant (5 mbar). La construction d’un analyseur d’électron capable de fonctionner à des pressions de l’ordre du mbar, c’est-à-dire à des pressions 7 ordres de grandeur supérieures à l’UHV, a été une avancée à la fois conceptuelle et technologique. Un système de pompage différentiel permet de maintenir l’échantillon dans des conditions dites environnementales tout en maximisant le libre parcours moyen des électrons de façon à ce qu’ils atteignent l’analyseur. De plus, des tensions sont appliquées à des lentilles électrostatiques dans le but d’accélérer et de focaliser ces électrons.Un système similaire (Near Ambient Pressure XPS, NAP-XPS) a été installé sur la ligne TEMPO du synchrotron Soleil en février 2013, le premier temps de faisceau ayant eu lieu au mois de mai suivant. Durant ma thèse, deux projets différents ont été développés, tous les deux liés à l’étude d’interfaces avec l’utilisation de la NAP-XPS.Le premier projet traite des procédés utilisés en micro-electronique pour déposer de fines couches d’oxydes : le dépôt chimique en phase vapeur (CVD) et la déposition de couches atomiques (ALD). En particulier, des molécules de la famille des silanes sont utilisées pour fonctionnaliser des surfaces d’oxyde de silicium ou comme précurseur, combiné à un agent oxydant comme l’eau pour le dépôt de films mince d’oxyde de silicium. Cependant, les mécanismes réactionnels des silanes sur les surfaces de silicium n’ont jamais été étudiés par des techniques telles que la microscopie a effet tunnel (STM) ou l’XPS et l’on sait peu de choses concernant leur mécanisme de dissociation et l’adsorption des divers fragments sur la surface
In many processes or technological objects, such as coating deposition, advanced material processing for electronics, magnetic or optical devices, electrochemical processes at an electrode, sensors and catalysis, etc. the interface between a surface of a solid and a liquid or a gas phase, plays a prominent role. Analogously, environmental sciences and sciences of the Living integrate into their models chemical reactions taking place at solid/liquid or liquid/gas interfaces.XPS is a powerful technique for interface analysis and has been widely use in the case of solid surface. The main advantage of XPS is its sensitivity to the material surface. Indeed, due to the low electron mean free path of electrons in a solid, only the photoelectrons at the extreme outer surface (1-10 nm) can escape the sample. However, XPS has traditionally been conducted under ultra-high vacuum (UHV) conditions. UHV conditions are utilized for two reasons. First, the analyzers are designed to work under UHV conditions. Second, the electrons must reach the detector and their mean free path is short at high pressures. For example at a pressure of 1 mbar, 100 eV electrons will travel 1 mm while under UHV conditions, the mean free path increases to 105 m. UHV chambers (10-10 mbar) help maximize the mean free path so that a high number of electrons will reach the detector/analyzer and the signal/noise ratio will increase making it possible to analyze the spectrum produced. This constraint makes UHV the standard environment of X-ray Photoelectron Spectroscopy (XPS) experiments.In order to make possible the use of XPS on a larger pressure range, a few groups around the world have designed photoemission equipment that can be operated under ambient pressure (up to 5 mbar). The Berkeley group (M. Salmeron LBNL-Materials Sciences Division, H. Bluhm LBNL-Chemical Sciences Division), who pioneered this field, has two such setups installed at the Advanced Light Source. The Fritz Haber Institute has built a high pressure XPS based on the Berkeley prototype, installed at BESSY synchrotron (Berlin), since 2002. The building of Ambient Pressure XPS (APXPS) analyzers of the Berkeley type, able to be operated at pressures in the range of 1 mbar, about 7 orders of magnitude higher than the pressure limit of conventional UHV equipment is both a technological and conceptual breakthrough. Differential pumping stages allow the sample to remain at environmental pressures, while maximizing the mean free path of emitted electrons, so they can reach the detector. Additionally, voltages are applied to electrostatic lenses in the unit to accelerate and focus the electrons onto the focal plane of the electron energy analyzer. A similar system Near-Ambient Pressure XPS, NAP-XPS), described in details in chapter 1, was delivered in December 2012 and installed at TEMPO beamline in February 2013. The first beamtime occurred in May 2013. During my thesis that started in October 2011 two different projects were developed, both related to interface analysis using the NAP-XPS instrument

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Gilmore, Tim. "Evaluation of Various Inspiratory Times and Inflation Pressures During Airway Pressure Release Ventilation". Diss., NSUWorks, 2017. https://nsuworks.nova.edu/hpd_hs_stuetd/5.

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There are few recommendations on how best to apply certain modes of mechanical ventilation. The application of Airway Pressure Release Ventilation (APRV) includes strategic implementation of specific inspiratory times (I-times) and particular mean airway pressures (MAWP) neither of which is standardized. This study utilized a retrospective analysis of archived electronic health record data to evaluate the clinical outcomes of adult patients that had been placed on APRV for at least 8 hours. 68 adult subjects were evaluated as part of a convenient purposive sample. All outcomes of interest (surrogates) for short-term clinical outcomes to include the PaO2/FiO2 (P/F) ratio, Oxygen Index and Oxygen Saturation Index (OI; OSI), and Modified Sequential Organ Failure Assessment (MSOFA) scores showed improvement after at least 8 hours on APRV. Most notably, there was significant improvement in P/F ratio (p = .012) and OSI (p = .000). Results of regression analysis showed P low as a statistically significant negative predictor of pre-APRV P/F ratio with a higher initial P low coinciding with a lower P/F ratio. The regression analysis also showed MAWP as a significant positive predictor of post-APRV OSI and P high and P low as significant negative predictors of post-APRV MSOFA scores. In summary, it was found that settings for P high, Plow, and T low in addition to overall MAWP and Body Mass Index (BMI) had significant correlation to impact at least one of the short-term clinical outcomes measured.

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Kempson, Ruth, i Ronnie Cann. "Dialogue pressures and syntactic change". Universität Potsdam, 2006. http://opus.kobv.de/ubp/volltexte/2006/1046/.

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On the basis of the Dynamic Syntax framework, this paper argues that the production pressures in dialogue determining alignment effects and given versus new informational effects also drive the shift from case-rich free word order systems without clitic pronouns into systems with clitic pronouns with rigid relative ordering.
The paper introduces assumptions of Dynamic Syntax, in particular the building up of interpretation through structural underspecification and update, sketches the attendant account of production with close coordination of parsing and production strategies, and shows how what was at the Latin stage a purely pragmatic, production-driven decision about linear ordering becomes encoded in the clitics in theMedieval Spanish system which then through successive steps of routinization yield the modern systems with immediately pre-verbal fixed clitic templates.

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Evans, Jodi K. "Institutional pressures for sustainable development". Thesis, University of Oxford, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.361738.

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Moore, Stephen Richard. "Earth pressures on spillthrough abutments". Thesis, University of Surrey, 1985. http://epubs.surrey.ac.uk/843896/.

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The earth pressures exerted by cohesionless backfill against spill through abutments have been investigated by instrumenting two full size structures with vibrating wire earth pressure cells which were calibrated in soil under laboratory conditions. The abutment deformations were recorded with inclinometer tubes and precise surveying techniques, and the column bending was measured using vibrating wire strain gauges. The earth pressures were found to be influenced by the concrete expansion during hydration which caused transverse bending of the columns after the capping beam pour, as well as longitudinal backward rotations and bending of the abutments after the deck slab pours. High residual lateral earth pressures were exerted against the rear of the capping beams due to heavy compaction of the backfill at this level, thus causing the abutment to rotate forwards and become effectively propped by the deck slab. Traffic loading and deck slab temperature fluctuations were found to cause seasonal earth pressure variations. The lateral earth pressure profiles as predicted by the existing design methods were found to be totally unrepresentative of the Wisley results, and a modified design approach has been proposed. Model tests were performed in the laboratory to investigate the behaviour of embedded laterally loaded columns within a spill through abutment. At small lateral displacements, the friction of the soil against the column sides was found to contribute significantly to the total soil resistance. Soil deformations were measured using specialised photography and the interaction between columns was found to be negligible. A nuclear density probe was compared with other common methods of measuring the in-situ density of compacted backfill. A modified resin impregnation technique was developed to measure the density variations within a laboratory test specimen of dry sand.

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Książki na temat "Pressures"

Ballard, Dawna. Work Pressures. New York, NY : Routledge, 2017. | Series: New agendas in: Routledge, 2016. http://dx.doi.org/10.4324/9781315675749.

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S, Kirkbride Paul, red. Globalization: The external pressures. Chichester: Wiley, 2001.

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Blair, Margaret M. Industry-level pressures to restructure. Boston, MA: Boston University, School of Management, 1992.

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Mass migration pressures in China. Tokyo, Japan: International Institute for Gloal Peace, 1992.

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Mayes, David, Wolfgang Hager, Arthur Knight i Wolfgang Streeck. Public Interest and Market Pressures. London: Palgrave Macmillan UK, 1993. http://dx.doi.org/10.1007/978-1-349-22744-0.

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Hallsworth, A. G. Financial pressures and retail change. Portsmouth: Portsmouth Polytechnic, 1991.

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1939-, Matsumoto Kiyoshi, i Acheson R. M, red. Organic synthesis at high pressures. New York: Wiley, 1991.

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Boote, Bob. Age potential: Pressures and responses. Berkhamsted: Volunteer Centre, 1994.

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Pressure Vessels and Piping Conference (1988 Pittsburgh, Pa.). High pressure technology: Material, design, stress analysis, and applications : presented at the 1988 ASME Pressure Vessels and Piping Conference, Pittsburgh, Pennsylvania, June 19-23, 1988. New York, N.Y. (345 E. 47th St., New York 10017): American Society of Mechanical Engineers, 1988.

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Les, Antalffy, Picqueur L. M, American Society of Mechanical Engineers. Pressure Vessels and Piping Division. i Pressure Vessels and Piping Conference (1997 : Orlando, Fla.), red. High pressure technology 1997: Presented at the 1997 ASME Pressure Vessels and Piping Conference, Orlando, Florida, July 27-31, 1997. New York, N.Y: American Society of Mechanical Engineers, 1997.

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Części książek na temat "Pressures"

Clough, G. W., i J. M. Duncan. "Earth Pressures". W Foundation Engineering Handbook, 223–35. Boston, MA: Springer US, 1991. http://dx.doi.org/10.1007/978-1-4615-3928-5_6.

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Walters, R. B. "Working Pressures". W Hydraulic and Electric-Hydraulic Control Systems, 8–9. Dordrecht: Springer Netherlands, 2000. http://dx.doi.org/10.1007/978-94-015-9427-1_3.

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Verruijt, Arnold. "Pore Pressures". W An Introduction to Soil Mechanics, 187–95. Cham: Springer International Publishing, 2017. http://dx.doi.org/10.1007/978-3-319-61185-3_23.

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Chetham, Deirdre. "Outside Pressures". W Before the Deluge, 71–89. New York: Palgrave Macmillan US, 2002. http://dx.doi.org/10.1007/978-1-4039-8126-4_5.

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Walters, R. B. "Working Pressures". W Hydraulic and Electro-Hydraulic Control Systems, 8–9. Dordrecht: Springer Netherlands, 1991. http://dx.doi.org/10.1007/978-94-011-3840-6_3.

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Christians, Clifford G., Mark Fackler, Kathy Brittain Richardson i Peggy J. Kreshel. "Institutional Pressures". W Media Ethics, 45–69. 11th edition. | London ; New York : Routledge, 2020.: Routledge, 2020. http://dx.doi.org/10.4324/9780429282249-1.

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De Backer, Daniel. "Pulmonary Pressures". W Advanced Hemodynamic Monitoring: Basics and New Horizons, 31–37. Cham: Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-71752-0_4.

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Rosano, Matt. "Selection Pressures". W Encyclopedia of Sciences and Religions, 2121. Dordrecht: Springer Netherlands, 2013. http://dx.doi.org/10.1007/978-1-4020-8265-8_200103.

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Staten, Adam. "External pressures". W GP Wellbeing, 11–18. Boca Raton : CRC Press, [2018]: CRC Press, 2017. http://dx.doi.org/10.1201/9781315159218-2.

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Holmes, John D., i Seifu A. Bekele. "Internal pressures". W Wind Loading of Structures, 197–218. Fourth edition. | Boca Raton : CRC Press, 2021. |: CRC Press, 2020. http://dx.doi.org/10.1201/9780429296123-6.

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Streszczenia konferencji na temat "Pressures"

Kettenbeil, Christian, Zev Lovinger, Suraj Ravindran, M. Mello i G. Ravichandran. "Pressure-shear plate impact experiments at very high pressures". W SHOCK COMPRESSION OF CONDENSED MATTER - 2019: Proceedings of the Conference of the American Physical Society Topical Group on Shock Compression of Condensed Matter. AIP Publishing, 2020. http://dx.doi.org/10.1063/12.0001099.

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Biteau, J. J., M. O. Spencer, B. Benazet i C. Longis. "Origin of Abnormal Pressures, Hydrodynamism and Pore Pressure Prediction". W 76th EAGE Conference and Exhibition - Workshops. Netherlands: EAGE Publications BV, 2014. http://dx.doi.org/10.3997/2214-4609.20140597.

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Palm, Peter, Dirk Hanke, Manfred Mürtz, Bertold Frech i Wolfgang Urban. "Pressure broadening and saturation lineshapes of CO at pressures between". W SPECTRAL LINE SHAPES. ASCE, 1999. http://dx.doi.org/10.1063/1.58391.

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Ravindran, Suraj, Zev Lovinger, Christian Kettenbeil, Michael Mello i Guruswami Ravichandran. "Pressure-shear plate impact experiments of magnesium at high pressures". W SHOCK COMPRESSION OF CONDENSED MATTER - 2019: Proceedings of the Conference of the American Physical Society Topical Group on Shock Compression of Condensed Matter. AIP Publishing, 2020. http://dx.doi.org/10.1063/12.0001022.

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Gamal, Ahmed M., Bugra H. Ertas i John M. Vance. "High-Pressure Pocket Damper Seals: Leakage Rates and Cavity Pressures". W ASME Turbo Expo 2006: Power for Land, Sea, and Air. ASMEDC, 2006. http://dx.doi.org/10.1115/gt2006-90858.

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The turbomachinery component of interest in this paper, the pocket damper seal, has the dual purpose of limiting leakage and providing an additional source of damping at the seal location. The rotordynamic coefficients of these seals (primarily the direct stiffness and damping) are highly dependent on the leakage rates through the seals and the pressures in the seals’ cavities. This paper presents both numerical predictions and experimentally obtained results for the leakage and the cavity pressures of pocket damper seals operating at high pressures. The seals were tested with air, at pressures up to 1000 Psi (6.92 MPa), as the working fluid. Earlier flow-prediction models were modified and used to obtain theoretical reference values for both mass flow-rates and pressures. Leakage and static pressure measurements on straight-through and diverging-clearance configurations of eight-bladed and twelve-bladed seals were used for code validation and for calculation of seal discharge coefficients. Higher than expected leakage rates were measured in the case of the twelve-bladed seal, while the leakage rates for the eight-bladed seals were predicted with reasonable accuracy. Differences in the axial pitch lengths of the cavities and the blade profiles of the seals are used to explain the discrepancy in the case of the twelve-bladed seal. The analysis code used also predicted the static cavity pressures reasonably well. Tests conducted on a six-bladed pocket damper seal to further investigate the effect of blade profile supported the results of the eight-bladed and twelve-bladed seal tests and matched theoretical predictions with satisfactory accuracy.

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Jun’ichi Sato, Mitsuhiro Tsue, Mario Niwa i Michikata Kono. "Microgravity droplet combustion in high pressures near critical pressures of fuels". W Drops and bubbles: third international colloquium. AIP, 1990. http://dx.doi.org/10.1063/1.38971.

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Aly, Ahmed, Her-Yuan Chen i W. J. Lee. "Pre-Production Pressure Analysis of Commingled Reservoir With Unequal Initial Pressures". W Permian Basin Oil and Gas Recovery Conference. Society of Petroleum Engineers, 1994. http://dx.doi.org/10.2118/27661-ms.

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Gregory, James. "Porous Pressure-Sensitive Paint for Measurement of Unsteady Pressures in Turbomachinery". W 42nd AIAA Aerospace Sciences Meeting and Exhibit. Reston, Virigina: American Institute of Aeronautics and Astronautics, 2004. http://dx.doi.org/10.2514/6.2004-294.

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Walker, Henry. "Principles, priorities, and pressures". W Proceeding of the 44th ACM technical symposium. New York, New York, USA: ACM Press, 2013. http://dx.doi.org/10.1145/2445196.2445199.

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McCoy, J. N., A. L. Podio, K. L. Huddleston i B. Drake. "Acoustic Static Bottomhole Pressures". W SPE Production Operations Symposium. Society of Petroleum Engineers, 1985. http://dx.doi.org/10.2118/13810-ms.

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Raporty organizacyjne na temat "Pressures"

Goldberg, Linda, i Signe Krogstrup. International Capital Flow Pressures. Cambridge, MA: National Bureau of Economic Research, luty 2018. http://dx.doi.org/10.3386/w24286.

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Moulton, N. E., S. A. Wolf, E. F. Skelton i D. H. Liebenberg. Pressure Dependence of Tc in Tl2Ba2CaCu2O8 at Hydrostatic Pressures to 6 GPa. Fort Belvoir, VA: Defense Technical Information Center, październik 1991. http://dx.doi.org/10.21236/ada243433.

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Kelkar, Sharad. Fracturing Pressures in EE-3A. Office of Scientific and Technical Information (OSTI), wrzesień 1985. http://dx.doi.org/10.2172/1321626.

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Campbell, C. S., K. Rahman, X. Hu, C. Jin i A. V. Potapov. Particle pressures in fluidized beds. Office of Scientific and Technical Information (OSTI), styczeń 1992. http://dx.doi.org/10.2172/7025427.

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Vargas-Herrera, Hernando, Andrés González-Gómez, Eliana Rocío González-Molano, José Vicente Romero-Chamorro i Luis Eduardo Rojas. Assessing inflationary pressures in Colombia. Bogotá, Colombia: Banco de la República, kwiecień 2009. http://dx.doi.org/10.32468/be.558.

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Wolfer, W. G. Phonon Drag Dislocations at High Pressures. Office of Scientific and Technical Information (OSTI), październik 1999. http://dx.doi.org/10.2172/793838.

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Campbell, C. S., K. Rahman, X. Hu i C. Jin. Particle pressures in fluidized beds. Annual report. Office of Scientific and Technical Information (OSTI), marzec 1994. http://dx.doi.org/10.2172/304008.

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Veletsos, A. S., i A. H. Younan. Dynamic soil pressures on rigid vertical walls. Office of Scientific and Technical Information (OSTI), grudzień 1992. http://dx.doi.org/10.2172/10135317.

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Welch, K. M. RHIC detector beam-pipe pressures in time. Office of Scientific and Technical Information (OSTI), luty 1993. http://dx.doi.org/10.2172/10141205.

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Veletsos, A. S., i A. H. Younan. Dynamic soil pressures on rigid cylindrical vaults. Office of Scientific and Technical Information (OSTI), luty 1993. http://dx.doi.org/10.2172/6419662.

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