carbon dioxide

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carbon dioxide

 
an odorless, colorless gas, CO2, resulting from oxidation of carbon, formed in the tissues and eliminated by the lungs; used in some pump oxygenators to maintain the carbon dioxide tension in the blood. It is also used in solid form; see carbon dioxide snow and carbon dioxide slush.
carbon dioxide combining power the ability of blood plasma to combine with carbon dioxide; indicative of the alkali reserve and a measure of the acid-base balance of the blood.
carbon dioxide content the amount of carbonic acid and bicarbonate in the blood; reported in millimoles per liter.
carbon dioxide–oxygen therapy administration of a mixture of carbon dioxide and oxygen (commonly 5 per cent CO2 and 95 per cent O2 or 10 per cent CO2 and 90 per cent O2); used for improvement of cerebral blood flow, stimulation of deep breathing, or treatment of singultation (hiccupping). Carbon dioxide acts by stimulating the respiratory center; it also increases heart rate and blood pressure. Therapy is given for 6 minutes or less with a 5 per cent mixture and 2 minutes or less with a 10 per cent mixture. Potential adverse effects include headache, dizziness, dyspnea, nausea, tachycardia and high blood pressure, blurred vision, mental depression, coma, and convulsions.
carbon dioxide slush solid carbon dioxide combined with a solvent such as acetone, and sometimes also alcohol; used as an escharotic to treat skin lesions such as warts and moles and as a peeling agent in chemabrasion.
carbon dioxide snow the solid formed by rapid evaporation of liquid carbon dioxide, giving a temperature of about −79°C (−110°F). It has been used in cryotherapy to freeze the skin, thus producing local anesthesia and arrest of blood flow. See also carbon dioxide slush.
Miller-Keane Encyclopedia and Dictionary of Medicine, Nursing, and Allied Health, Seventh Edition. © 2003 by Saunders, an imprint of Elsevier, Inc. All rights reserved.

car·bon di·ox·ide (CO2),

the product of the combustion of carbon with an excess of oxygen; in concentrations not less than 99.0% by volume of CO2.
Farlex Partner Medical Dictionary © Farlex 2012

carbon dioxide

n.
A colorless, odorless, incombustible gas, CO2, that is formed during respiration, combustion, and organic decomposition, is an essential component in photosynthesis, and is used in food refrigeration, carbonated beverages, inert atmospheres, fire extinguishers, and aerosols. Also called carbonic acid gas.
The American Heritage® Medical Dictionary Copyright © 2007, 2004 by Houghton Mifflin Company. Published by Houghton Mifflin Company. All rights reserved.

carbon dioxide

CO2 Physiology A metabolic byproduct of carbohydrate metabolism; it accumulates in tissues, is released to the blood in veins, and is eliminated via the lungs
McGraw-Hill Concise Dictionary of Modern Medicine. © 2002 by The McGraw-Hill Companies, Inc.

car·bon di·ox·ide

(CO2) (kahr'bŏn dī-oks'īd)
The product of the combustion of carbon with an excess of air; in concentrations not less than 99.0% by volume of CO2, used as a respiratory stimulant.
Medical Dictionary for the Health Professions and Nursing © Farlex 2012

carbon dioxide

A compound in which an atom of carbon is linked to two atoms of oxygen (CO2 ). Carbon dioxide is a colourless, odourless gas and is one of the chief waste products of tissue metabolism.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005

carbon dioxide

a colourless, odourless gas, heavier than air, produced in respiration of organisms, and utilized to form sugars in PHOTOSYNTHESIS. Formula: CO2 .
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005

Carbon dioxide

A heavy, colorless gas that dissolves in water.
Mentioned in: Laser Surgery
Gale Encyclopedia of Medicine. Copyright 2008 The Gale Group, Inc. All rights reserved.

hypercapnia

The presence of a raised carbon dioxide content or tension in a milieu (e.g. blood, tears). Contact lens wear tends to give rise to this condition, especially lenses of low gas transmissibility. See acidosis.
Millodot: Dictionary of Optometry and Visual Science, 7th edition. © 2009 Butterworth-Heinemann

car·bon di·ox·ide

(CO2) (kahr'bŏn dī-oks'īd)
Product of the combustion of carbon with an excess of oxygen.
Medical Dictionary for the Dental Professions © Farlex 2012
References in periodicals archive ?
Elbel and Hrnjak [6] and Elbel [7] experimentally investigated a transcritical R744 system using a refrigerant ejector.
Less attention has been given to low-pressure working fluids in the literature for ejector cooling cycles compared with R744 due to their lower work recovery potential.
Elbel and Hrnjak [6] were the first researchers to publish experimental results of introducing a variable two-phase ejector to a transcritical R744 system by installing a needle in the motive nozzle to control the motive nozzle throat diameter.
[5.] Banasiak, K., Hafiner, A., and Andresen, T., "Experimental and numerical investigation of the influence of the two-phase ejector geometry on the performance of the R744 heat pump," International Journal of Refrigeration, 35(6): 1617-1625, 2012.
ixetic's R744 compressors will increase the efficiency of future Mobile Air Conditioning (MAC) systems substantially.
ACC Appliances Components Companies, Madison, Alabama, USA, has also gotten into C[O.sub.2] (R744) systems as well as a high efficiency range that is said to cut energy consumption by 20% compared to standard compressors; the new units, introduced at the AHR Expo New Product Technology Theater in January, are available for R134A and R404A, for LBP and HMBP applications.
Source - CIBSE [k] Refrigerant Global Warming Potential 100 Year Time Horizon (GWP100) R11 (CFC-11) 4000 R12 (CFC-12) 8500 R22 (HCFC-22) 1700 R123 (HCFC-123) 93 R134a (HFC-134a) 1300 R404A (HFC-404A) 3800 R407C (HFC-407C) 1600 R410A (HFC-417A) 1900 R417A (HFC417A) 1950 R290 (propane) 3 R600a (isobutane) 3 R717 (ammonia) 0 R744 (Carbon 1 Dioxide)
Carbon Dioxide (R744) was a well known and widely accepted refrigerant in the early 1900's, but its popularity reduced with the introduction of fluorocarbons.
R744 has some very attractive properties, which makes it destined to be used as a working fluid.
Peter Neksa has already proved the advantages of using R744 for water and space heating applications.