Search results
Results from the WOW.Com Content Network
As mentioned, HPLC relies on pumps to pass a pressurized liquid and a sample mixture through a column filled with adsorbent, leading to the separation of the sample components. The active component of the column, the adsorbent, is typically a granular material made of solid particles ( e.g. , silica , polymers, etc.), 1.5–50 μm in size, on ...
Liquid chromatography as we know it today really got its start in 1969, when the first modern HPLC was designed and marketed as a nucleic acid analyzer. [9] Columns throughout the 1970s were unreliable, pump flow rates were inconsistent, and many biologically active compounds escaped detection by UV and fluorescence detectors. Focus on ...
Convection of the sample occurs by laminar flow, in which the linear velocity of the sample at the tube's walls is zero, while the sample at the center of the tube moves with a linear velocity twice that of the carrier stream. The result is the parabolic flow profile, before the sample passes through a detector to a waste container. [7]
Silica gel particles are commonly used as a stationary phase in high-performance liquid chromatography (HPLC) for several reasons, [13] [14] including: High surface area: Silica gel particles have a high surface area, allowing direct interactions with solutes or after bonding of variety of ligands for versatile interactions with the sample molecules, leading to better separations.
A typical APCI source usually consists of three main parts: a sample inlet, a corona discharge needle, and an ion transfer region under intermediate pressure. [5] In the case of the heated nebulizer inlet [ 7 ] from an LC, as shown in the figure, the eluate flows at 0.2 to 2.0 mL/min into a pneumatic nebulizer which creates a mist of fine droplets.
Two-dimensional chromatography is a type of chromatographic technique in which the injected sample is separated by passing through two different separation stages. Two different chromatographic columns are connected in sequence, and the effluent from the first system is transferred onto the second column. [ 1 ]
A process flow diagram (PFD) is a diagram commonly used in chemical and process engineering to indicate the general flow of plant processes and equipment. The PFD displays the relationship between major equipment of a plant facility and does not show minor details such as piping details and designations.
A control chart is a more specific kind of run chart. The control chart is one of the seven basic tools of quality control, which also include the histogram, pareto chart, check sheet, cause and effect diagram, flowchart and scatter diagram. Control charts prevent unnecessary process adjustments, provide information about process capability ...