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  2. High-performance liquid chromatography - Wikipedia

    en.wikipedia.org/wiki/High-performance_liquid...

    Pumps vary in pressure capacity, but their performance is measured on their ability to yield a consistent and reproducible volumetric flow rate. Pressure may reach as high as 60 MPa (6000 lbf/in 2), or about 600 atmospheres. Modern HPLC systems have been improved to work at much higher pressures, and therefore are able to use much smaller ...

  3. Pressure experiment - Wikipedia

    en.wikipedia.org/wiki/Pressure_experiment

    The equipment used for pressure experiments depends on whether the pressure is to be increased or decreased and by how much. A vacuum pump is used to remove the air out of a vacuum vessel for low-pressure experiments. High-pressures can be created with a piston-cylinder apparatus, up to 5 GPa (50 000 bar) and ~2000 °C.

  4. Diffusion - Wikipedia

    en.wikipedia.org/wiki/Diffusion

    This creates a pressure gradient between the air outside the body at relatively high pressure and the alveoli at relatively low pressure. The air moves down the pressure gradient through the airways of the lungs and into the alveoli until the pressure of the air and that in the alveoli are equal, that is, the movement of air by bulk flow stops ...

  5. French pressure cell press - Wikipedia

    en.wikipedia.org/wiki/French_pressure_cell_press

    The French pressure cell press, or French press, is an apparatus used in biological experimentation to disrupt the plasma membrane of cells by passing them through a narrow valve under high pressure. [1] The French press can also be used for disintegration of chloroplasts, homogenates of animal tissue, and other biological particles.

  6. Phase diagram - Wikipedia

    en.wikipedia.org/wiki/Phase_diagram

    The pressure on a pressure-temperature diagram (such as the water phase diagram shown above) is the partial pressure of the substance in question. A phase diagram in physical chemistry , engineering , mineralogy , and materials science is a type of chart used to show conditions (pressure, temperature, etc.) at which thermodynamically distinct ...

  7. Standard temperature and pressure - Wikipedia

    en.wikipedia.org/wiki/Standard_temperature_and...

    Since 1982, STP has been defined as a temperature of 273.15 K (0 °C, 32 °F) and an absolute pressure of exactly 1 bar (100 kPa, 10 5 Pa). NIST uses a temperature of 20 °C (293.15 K, 68 °F) and an absolute pressure of 1 atm (14.696 psi, 101.325 kPa). [3] This standard is also called normal temperature and pressure (abbreviated as NTP).

  8. Ion chromatography - Wikipedia

    en.wikipedia.org/wiki/Ion_chromatography

    Chamber (left) contains high salt concentration. Stirred chamber (right) contains low salt concentration. Gradual stirring causes the formation of a salt gradient as salt travel from high to low concentrations. Comparatively simple devices are often used to apply counterions of increasing gradient to a chromatography column. Counterions such as ...

  9. Dialysis (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Dialysis_(chemistry)

    Dialysis is the process used to change the matrix of molecules in a sample by differentiating molecules by the classification of size. [6] [7] It relies on diffusion, which is the random, thermal movement of molecules in solution (Brownian motion) that leads to the net movement of molecules from an area of higher concentration to a lower concentration until equilibrium is reached.