SCIENCE|natural and applied sciences|physical sciences|chemistry
- rótar guairneach Tagairt Faomhadh an téarma seo mar chuid de Thionscadal Lex
- ga
- spinning rotor | method
- en
- Sainmhíniú a method for calculating the vapour pressure ( IATE:1590631 ). It uses a spinning rotor viscosity gauge, in which the measuring element is a small steel ball which, suspended in a magnetic field, is made to spin by rotating fields. Pick-upcoils allow its spinning rate to be measured. When the ball has reached a given rotational speed, usually about 400 revolutions per second, energizing is stopped and deceleration, due to gas friction, takes place. The drop of rotational speed is measured as a function of time. The vapour pressure isdeduced from the pressure-dependent slow-down of the steel ball. The recommended range is 10-4 to0.5 Pa. Tagairt Based on: OECD Guideline for the testing of chemicals Adopted:27.07.95 http://www.oecd.org/dataoecd/17/34/1948161.pdf [2.12.2009]
- Nóta There are different ways to calculate the vapour pressure: a) by the effusion method ( IATE:3502097 ), that is either i) by vapour pressure balance ( IATE:3511133 ), or ii) by loss of weight ( IATE:1385761 ), or iii) by trapping vaporisate ( IATE:3511134 )b) by the gas saturation method ( IATE:3508924 ) c) by the spinning rotor method
- jauge à rotor
- fr
- Sainmhíniú Dans la jauge à rotor, l'élément de mesure réel est une petite bille d'acier en suspension dans un champ magnétique qui est soumise à une rotation à grande vitesse. La pression du gaz est déduite du ralentissement de la bille d'acier dû à la pression Tagairt Règlement (CE) n° 440/2008 de la Commission du 30 mai 2008 établissant des méthodes d'essai conformément au règlement (CE) n° 1907/2006 du Parlement européen et du Conseil concernant l'enregistrement, l'évaluation et l'autorisation des substances chimiques, ainsi que les restrictions applicables à ces substances (REACH) , http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2008:142:0001:0739:FR:PDF