Electrical resistivity and conductivity ions. In biological membranes, currents are carried by ionic salts. Small holes in cell membranes, called ion channels, are selective to specific ions and determine the membrane resistance. The electrical resistivity of a metallic conductor decreases gradually as temperature is lowered. In ordinary conductors, such as copper or silver, this decrease is limited by impurities and other defects. Even near absolute zero, a real sample of a normal conductor shows some resistance. In a superconductor, the resistance drops abruptly to zero when the material is cooled below its critical temperature. An electric current flowing in a loop of superconducting wire
Electrical conductivity meter the way temperature affects the conductivity "of a solution" can be modeled linearly using the following formula: where The temperature compensation slope for most naturally occurring waters is about 2%/°C, however it can range between 1 and 3%/°C. The compensation slope for some common water solutions are listed in the table below. Conductivity measurement is a versatile tool in process control. The measurement is simple, fast and most advanced sensors require only a little maintenance. The measured conductivity reading can be used to make various assumptions on what is happening in the process. In some cases it is possible to