Sensor Principle

Electrochemical Gas Sensors in General Electrochemical sensors operate by reacting with the analyte and producing an electrical signal. Most electrochemical gas sensors are amperometric sensors, generating a current that is linearly proportional to the gas concentration. The principle behind amperometric sensors is the measurement of the current-potential relationship in an electrochemical cell where equilibrium is…

Accuracy

Definitions “Accuracy” as defined in the ANSI/ISA—51.1—1979 (R1993) standard Process Instrumentation Terminology is: [T]he degree of conformity of an indicated value to a recognized accepted standard value, or ideal value. Two common methods of rating or expressing accuracy are: As a percent of scale length (or percent of full scale). This rating method is most…

All you need to know about pH

The classical first year chemistry definition of “pH” refers back to Danish biochemist Søren Sørenson, who originated the term, alluding to the “potential of hydrogen ion.” Specifically, pH is the negative logarithm of the molar concentration of the hydrogen ion (H+) in the particular solution. This is usually expressed as a formula… pH = -log[H+]…

Ethylene And Fruit Ripening

How about a little peak into the secret life of plants? Fruit ripening is a form of senescence and signifies the final stage in fruit development. Ripening, of course, eventually leads to spoilage, so there are important commercial reasons to increase and control post-harvest longevity. Complicating matters, post-harvest longevity varies naturally. Strawberries, for example, last…