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Glass Electrode
A glass electrode is a type of ion-selective electrode made of a doped glass membrane that is sensitive to a specific ion. The most common application of ion-selective glass electrodes is for the measurement of pH. The pH electrode is an example of a glass electrode that is sensitive to hydrogen ions. Glass electrodes play an important part in the instrumentation for chemical analysis and physicochemical studies. The voltage of the glass electrode, relative to some reference value, is sensitive to changes in the activity of a certain type of ions. History The first studies of glass electrodes (GE) found different sensitivities of different glasses to change the medium's acidity (pH), due to the effects of the alkali metal ions. In 1906, M. Cremer, the father of Erika Cremer, determined that the electric potential that arises between parts of the fluid, located on opposite sides of the glass membrane is proportional to the concentration of acid (hydrogen ion concentration ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ion Selective Electrode
An ion-selective electrode (ISE), also known as a specific ion electrode (SIE), is a transducer (or sensor) that converts the activity (chemistry), activity of a specific ion dissolved in a Solution (chemistry), solution into an electrical potential. The voltage is theoretically dependent on the logarithm of the ionic activity, according to the Nernst equation. Ion-selective electrodes are used in analytical chemistry and biochemistry, biochemical/biophysics, biophysical research, where measurements of ionic concentration in an aqueous solution are required. Types of ion-selective membrane There are four main types of ion-selective membrane used in ion-selective electrodes (ISEs): glass, solid state, liquid based, and compound electrode. Glass membranes Glass membranes are made from an ion-exchange type of glass (silicate or chalcogenide). This type of ISE has good Binding selectivity, selectivity, but only for several single-charged cations; mainly H+, Na+, and Ag+. Chalcogenid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boris Nikolsky
Boris Petrovich Nikolsky (russian: Бори́с Петро́вич Нико́льский; – 4 January 1990) was a Soviet chemist and radiochemist Radiochemistry is the chemistry of radioactive materials, where radioactive isotopes of elements are used to study the properties and chemical reactions of non-radioactive isotopes (often within radiochemistry the absence of radioactivity leads to ..., academician of the Soviet Academy of Sciences, and professor of Saint Petersburg (then Leningrad) Leningrad State University, State University. Boris Nikolsky was a 1925 graduate of Saint Petersburg State University, Leningrad State University. In the 1930s he studied the ion exchange processes between aqueous solutions and solids. During that time Nikolsky developed the theory of ion exchange in glass electrodes. He derived equations that describe properties of glass electrodes as well as other types of ion-selective electrodes depending on chemical structure and multi-component comp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
