Contour line factors in a weather system. An isobar (from or "baros", meaning 'weight') is a line of equal or constant pressure on a graph, plot, or map; an isopleth or contour line of pressure. More accurately, isobars are lines drawn on a map joining places of equal average atmospheric pressure reduced to sea level for a specified period of time. In meteorology, the barometric pressures shown are reduced to sea level, not the surface pressures at the map locations. The distribution of isobars is closely related to the magnitude and direction of the wind field, and can be used to predict
Desorption atmospheric pressure photoionization is normally used in the presence of a matrix, such as matrix assisted laser desorption ionization (MALDI), but research has combined techniques of laser desoprtion in atmospheric pressure conditions to produce a method that does not use a matrix or discharge. This method is able to help with smaller compounds, and generates both positive and negative ions for detection. A transmission geometry is taken as the beam and spray are guided at a formula_3angle into the coupled MS. Studies have shown the detection of organic compounds such as: farnesene, squalene, tetradecahydro anthracene, 5-alpha cholestane, perylene, benzo perylene, coronene, tetra decylprene,