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Introduction
Published in Armen S. Casparian, Gergely Sirokman, Ann O. Omollo, Rapid Review of Chemistry for the Life Sciences and Engineering, 2021
Armen S. Casparian, Gergely Sirokman, Ann O. Omollo
Dalton’s Law states: The total pressure exerted by a mixture of gases is equal to the sum of the partial pressures of all the gases in the mixture. Each partial pressure is the pressure that the gas would exert if the other gases were not present.
Vacuum and Gas Kinetics
Published in Eiichi Kondoh, Micro- and Nanofabrication for Beginners, 2021
Partial pressure does not simply show the ratio of gas components. The rate of chemical reactions of the gases involved is proportional to the partial pressures of the gases. For instance, rate of oxidation becomes smaller as po2 decreases.
Basic Chemical Hazards to Human Health and Safety — I
Published in Jack Daugherty, Assessment of Chemical Exposures, 2020
The ability of hemoglobin to carry oxygen is directly proportional to the partial pressure of oxygen in the air we breathe. Our bodies have adapted to work efficiently when the volume percent of oxygen in the atmosphere is about twenty-one percent. Dalton’s law of partial pressures states that in any mixture of gases, the total pressure is the sum of the partial pressures of the component gases. The partial pressure of any component gas in the mixture is proportional to the percentage of its molecules in the total mixture, or, in other words, the volume fraction of the gas component. In the case of oxygen in air at sea level: PO2=Pair×%O2=760mmHg×0.21=160mmHg
Simulation of methanol steam reforming process for the production of hydrogen
Published in Indian Chemical Engineer, 2021
Fazil Qureshi, Faizan Ahmad, Mohammad Idrees, Ali Asif Khan, Sadaf Zaidi
A schematic diagram of the Membrane reactor is shown in Figure 2. Membrane reactor [10] is cylindrically equipped with a membrane which is inert in nature. The feed containing reactant is introduced into the centre tube which is reaction zone and filled with catalyst particles in it where the primary reaction occurs. The permeation zone in MR where sweep gas is introduced in counter current or co-current with respect to feeding take away permeated gases along with them. Driving force in the shell side is maintained by sweep gas with a very high flow rate which is enough for permission. This sweep gas reduces the partial pressure of the gases, which permeate through the membrane. The permeation of the gaseous component through the membrane takes place from the high partial pressure to low partial pressure. Thus permeation may be from either side of the membrane depends upon the partial pressure.
Oxygen depletion in enclosed spaces
Published in Journal of Marine Engineering & Technology, 2020
As opposed to the methodology used in other studies, our research aims to continuously monitor the oxygen depletion process in a model. This data allows us to determine the rate of oxygen depletion. Dalton’s Law of Partial Pressures states that for a mixture of gases in any container, the total pressure exerted is the sum of the partial pressures that each gas would exert if it were alone in that container. The standard atmosphere is a unit of pressure equal to 101.325 kPa. The partial pressures of each of the air components (in kPa) are equal to the percentage of that component. With the exception of oxygen and water vapour, all constituents of air are inert or unreactive gases; therefore oxygen and water vapour are the only gases which can be consumed in the rusting process. In a closed containment experiment if all the oxygen is used up by corrosion, the pressure in the container is 80.425 kPa which is equal to the atmospheric pressure minus the partial pressure of oxygen (20.9 kPa). Table 1 shows the relationship between the Oxygen level, the absolute pressure within the container and the level of danger within the space.
Experimental and Numerical Study of Autoignition/Deflagration Transition Limit in a Flat Piston Optical Rapid Compression Machine
Published in Combustion Science and Technology, 2023
Hicham Ossman, Camille Strozzi, Julien Sotton, Marc Bellenoue
The combustion chamber, cylinder, intake pipes, valves and pressure sensors are heated using a multi-zone regulated heating system in order to obtain a homogeneous or a stratified temperature distribution within the cylinder see section 3.2. For this purpose, the cylinder is separated in two heating zone warmed up through heating tapes. A third zone corresponding to the cylinder head is heated using a cartridge. This leads to different temperature gradients of a few Kelvins per millimeter after compression in the hottest core region. For convenience, they are referred to as Compressed Temperature Gradient (CTG) in the following. Initial temperature profile along the cylinder axis can be measured using a bare bead K thermocouple. Gaseous mixtures are prepared following the partial pressure method. Firstly, heated combustion chamber and feeding lines are placed under vacuum. N-heptane with high purity grade (>99%) is then injected using microliter syringes and a septum. Pressure of fuel is measured using 0–1300 mbar MKS Baratron 631 capacitive sensor heated at 470 K. To ensure the full vaporization of the fuel, the theoretical pressure of liquid fuel injected was compared to the measured fuel pressure and the difference was found to be lower than 2%. Finally, synthetic air (high purity 99.99% O2, N2, CO2) is then admitted through a heated tube to reach the required initial pressure. The operator waits one hour before starting the compression stroke. This is the ideal time slot to guarantee homogenization of the mixture. Pressure level is checked before the test to ensure that the pressure variation is lower than 2%.