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2. Barometer - Wikipedia

   en.wikipedia.org/wiki/Barometer

   Using vacuum pump oil as the working fluid in a barometer has led to the creation of the new "World's Tallest Barometer" in February 2013. The barometer at Portland State University (PSU) uses doubly distilled vacuum pump oil and has a nominal height of about 12.4 m for the oil column height; expected excursions are in the range of ±0.4 m over ...

3. Pirani gauge - Wikipedia

   en.wikipedia.org/wiki/Pirani_gauge

   A special form of the Pirani gauge is the pulsed Pirani vacuum gauge where the sensor wire is not operated at a constant temperature, but is cyclically heated up to a certain temperature threshold by an increasing voltage ramp. When the threshold is reached, the heating voltage is switched off and the sensor cools down again.

4. Pressure measurement - Wikipedia

   en.wikipedia.org/wiki/Pressure_measurement

   Moderate vacuum pressure readings can be ambiguous without the proper context, as they may represent absolute pressure or gauge pressure without a negative sign. Thus a vacuum of 26 inHg gauge is equivalent to an absolute pressure of 4 inHg, calculated as 30 inHg (typical atmospheric pressure) − 26 inHg (gauge pressure).

5. Torricelli's experiment - Wikipedia

   en.wikipedia.org/wiki/Torricelli's_experiment

   The experiment uses a simple barometer to measure the pressure of air, filling it with mercury up until 75% of the tube. Any air bubbles in the tube must be removed by inverting several times. After that, a clean mercury is filled once again until the tube is completely full. The barometer is then placed inverted on the dish full of mercury.

6. Mercury pressure gauge - Wikipedia

   en.wikipedia.org/wiki/Mercury_pressure_gauge

   The tube is sealed during manufacture with the sealed end containing a vacuum. [1] Mercury is a useful material to use in a manometer because of its high density. This means that a much shorter column is needed compared to water. [2] For instance, the pressure represented by a column of 100 mm of water is just under 7.4 mm of mercury . [3]

7. McLeod gauge - Wikipedia

   en.wikipedia.org/wiki/McLeod_gauge

   McLeod gauges operate by taking in a sample volume of gas from a vacuum chamber, then compressing it by tilting and infilling with mercury. The pressure in this smaller volume is then measured by a mercury manometer, and knowing the compression ratio (the ratio of the initial and final volumes), the pressure of the original vacuum can be ...

8. Schlenk line - Wikipedia

   en.wikipedia.org/wiki/Schlenk_line

   The inert-gas line is vented through an oil bubbler, while solvent vapors and gaseous reaction products are prevented from contaminating the vacuum pump by a liquid-nitrogen or dry-ice/acetone cold trap. Special stopcocks or Teflon taps allow vacuum or inert gas to be selected without the need for placing the sample on a separate line. [3]

9. Magdeburg hemispheres - Wikipedia

   en.wikipedia.org/wiki/Magdeburg_hemispheres

   The first artificial vacuum had been produced a few years earlier by Evangelista Torricelli and inspired Guericke to design the world's first vacuum pump, which consisted of a piston and cylinder with one-way flap valves. The hemispheres became popular in physics lectures as an illustration of the strength of air pressure, and are still used in ...