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Oxygen Equivalent
Oxygen equivalent compares the relative amount of oxygen Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as wel ... available for respiration at a variable pressure to that available at SATP. As external respiration depends on the exchange of gases due to partial pressures across a semipermeable membrane and normally occurs at SATP, an oxygen equivalent may aid in recognizing and managing variable oxygen availability during procedures such as hyperbaric oxygen therapy or medical air transport. It does so by expressing oxygen concentration as a ratio of the partial pressure of oxygen at a given altitude or pressure to Standard Atmospheric Pressure; rather than as a ratio of the PO2 at a given pressure to the total pressure of the gas mixture. The latter would generally be 0.2095, the at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxygen
Oxygen is the chemical element with the symbol O and atomic number 8. It is a member of the chalcogen group in the periodic table, a highly reactive nonmetal, and an oxidizing agent that readily forms oxides with most elements as well as with other compounds. Oxygen is Earth's most abundant element, and after hydrogen and helium, it is the third-most abundant element in the universe. At standard temperature and pressure, two atoms of the element bind to form dioxygen, a colorless and odorless diatomic gas with the formula . Diatomic oxygen gas currently constitutes 20.95% of the Earth's atmosphere, though this has changed considerably over long periods of time. Oxygen makes up almost half of the Earth's crust in the form of oxides.Atkins, P.; Jones, L.; Laverman, L. (2016).''Chemical Principles'', 7th edition. Freeman. Many major classes of organic molecules in living organisms contain oxygen atoms, such as proteins, nucleic acids, carbohydrates, and fats, as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Standard Ambient Temperature And Pressure
Standard temperature and pressure (STP) are standard sets of conditions for experimental measurements to be established to allow comparisons to be made between different sets of data. The most used standards are those of the International Union of Pure and Applied Chemistry (IUPAC) and the National Institute of Standards and Technology (NIST), although these are not universally accepted standards. Other organizations have established a variety of alternative definitions for their standard reference conditions. In chemistry, IUPAC changed its definition of standard temperature and pressure in 1982: * Until 1982, STP was defined as a temperature of 273.15 K (0 °C, 32 °F) and an absolute pressure of exactly 1 atm (101.325 kPa). * Since 1982, STP has been defined as a temperature of 273.15 K (0 °C, 32 °F) and an absolute pressure of exactly 105 Pa (100 kPa, 1 bar). STP should not be confused with the standard state comm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
External Respiration
In physiology, respiration is the movement of oxygen from the outside environment to the cells within tissues, and the removal of carbon dioxide in the opposite direction that's to the environment. The physiological definition of respiration differs from the biochemical definition, which refers to a metabolic process by which an organism obtains energy (in the form of ATP and NADPH) by oxidizing nutrients and releasing waste products. Although physiologic respiration is necessary to sustain cellular respiration and thus life in animals, the processes are distinct: cellular respiration takes place in individual cells of the organism, while physiologic respiration concerns the diffusion and transport of metabolites between the organism and the external environment. Gas exchanges in the lung occurs by ventilation and perfusion. Ventilation refers to the in and out movement of air of the lungs and perfusion is the circulation of blood in the pulmonary capillaries. In mammals, physi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Medical Air Transport
Medicine is the science and practice of caring for a patient, managing the diagnosis, prognosis, prevention, treatment, palliation of their injury or disease, and promoting their health. Medicine encompasses a variety of health care practices evolved to maintain and restore health by the prevention and treatment of illness. Contemporary medicine applies biomedical sciences, biomedical research, genetics, and medical technology to diagnose, treat, and prevent injury and disease, typically through pharmaceuticals or surgery, but also through therapies as diverse as psychotherapy, external splints and traction, medical devices, biologics, and ionizing radiation, amongst others. Medicine has been practiced since prehistoric times, and for most of this time it was an art (an area of skill and knowledge), frequently having connections to the religious and philosophical beliefs of local culture. For example, a medicine man would apply herbs and say prayers for healing, or an ancie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
