Search results
Results from the WOW.Com Content Network
A stirring rod is used for mixing liquids, or solids and liquids. Stir rods are used as part of proper laboratory technique when decanting supernatants because the contact helps to negate the adhesion between the side of the glassware and the supernatant that is responsible for the liquid running down the side. Using a stir rod also grants more ...
A magnetic stirrer or magnetic mixer is a laboratory device that employs a rotating magnetic field to cause a stir bar (or flea) immersed in a liquid to spin very quickly, thus stirring it. The rotating field may be created either by a rotating magnet or a set of stationary electromagnets, placed beneath the vessel with the liquid.
The liquids to be stirred are held in beakers, jars, or Erlenmeyer flasks that are placed over the table or, sometimes, in test tubes or vials that are nested into holes in the plate. [3] Platform shakers can also be combined with other systems like rotating mixers for small systems and have been designed to be manufactured in laboratories ...
The total rate of heat transfer between the hot and cold fluids passing through a plate heat exchanger may be expressed as: Q = UA∆Tm where U is the Overall heat transfer coefficient, A is the total plate area, and ∆Tm is the Log mean temperature difference. U is dependent upon the heat transfer coefficients in the hot and cold streams.
This type of water bath relies primarily on convection instead of water being uniformly heated. Therefore, it is less accurate in terms of temperature control. In addition, there are add-ons that provide stirring to non-circulating water baths to create more uniform heat transfer.
One of the laboratory brands, Huber, states in their user manuals that the laboratory circulators should not be used for food or medical uses. [3] A food-grade, rather than laboratory, circulator is advised for culinary use, even if unused.
A hot plate or hotplate is a heated flat surface on a stove or electric cooker on which food may be cooked. [3] It comprises a heated top which is flat and usually circular, and may be made of metal, ceramic, or heat-resistant glass, with resistive wire forming a heating element fitted underneath and a thermostat to control the temperature.
Drawing of a Thiele tube with red arrows showing convection current A photograph of a Thiele tube. The oil level is a little low now to compensate for expansion when heating commences.