A fuel cell is an electrochemical cell that converts the chemical energy from a fuel into electricity through an electrochemical reaction of hydrogen-containing fuel with oxygen or another oxidizing agent.
 Fuel cells are different from batteries in requiring a continuous source of fuel and oxygen (usually from air) to sustain the chemical reaction, whereas in a battery the chemical energy comes from chemicals already present in the battery.
 Fuel cells can produce electricity continuously for as long as fuel and oxygen are supplied.
Georg Simon Ohm (] ; 16 March 1789 – 6 July 1854) was a German physicist and mathematician.
 As a school teacher, Ohm began his research with the new electrochemical cell, invented by Italian scientist Alessandro Volta.
 Using equipment of his own creation, Ohm found that there is a direct proportionality between the potential difference (voltage) applied across a conductor and the resultant electric current.
 This relationship is known as Ohm's law.
The electrochemical regeneration of activated carbon based adsorbents involves the removal of molecules adsorbed onto the surface of the adsorbent with the use of an electric current in an electrochemical cell restoring the carbon’s adsorptive capacity.
 Electrochemical regeneration represents an alternative to thermal regeneration commonly used in waste water treatment applications.
 Common adsorbents include powdered activated carbon (PAC), granular activated carbon (GAC) and activated carbon fibre.
A metal–air electrochemical cell is an electrochemical cell that uses an anode made from pure metal and an external cathode of ambient air, typically with an aqueous electrolyte.
A salt bridge, in electrochemistry, is a laboratory device used to connect the oxidation and reduction half-cells of a galvanic cell (voltaic cell), a type of electrochemical cell.
 It maintains electrical neutrality within the internal circuit, preventing the cell from rapidly running its reaction to equilibrium.
 If no salt bridge were present, the solution in one half cell would accumulate negative charge and the solution in the other half cell would accumulate positive charge as the reaction proceeded, quickly preventing further reaction, and hence production of electricity.
Sonoelectrochemistry is the application of ultrasound in electrochemistry.
 Like sonochemistry, sonoelectrochemistry was discovered in the early 20th century.
 The effects of power ultrasound on electrochemical systems and important electrochemical parameters were originally demonstrated by Moriguchi and then by Schmid and Ehert when the researchers investigated the influence of ultrasound on concentration polarisation, metal passivation and the production of electrolytic gases in aqueous solutions.
 In the late 1950s, Kolb and Nyborg showed that the electrochemical solution (or electroanalyte) hydrodynamics in an electrochemical cell was greatly increased in the presence of ultrasound and described this phenomenon as "acoustic streaming".
 In 1959, Penn "et al." demonstrated that sonication had a great effect on the electrode surface activity and electroanalyte species concentration profile throughout the solution.
 In the early 1960s, the electrochemist Allen J. Bard showed in controlled potential coulometry experiments that ultrasound significantly enhances mass transport of electrochemical species from the bulk solution to the electroactive surface.
Electrochemical regeneration of activated carbon adsorbents such as granular activated carbon present an alternative to thermal regeneration or land filling at the end of useful adsorbent life.
 Continuous adsorption-electrochemical regeneration encompasses the adsorption and regeneration steps, typically separated in the bulk of industrial processes due to long adsorption equilibrium times (ranging from hours to months), into one continuous system.
 This is possible using a non-porous, electrically conducting carbon derivative called Nyex.
 The non-porosity of Nyex allows it to achieve its full adsorptive capacity within a few minutes and its electrical conductivity allows it to form part of the electrode in an electrochemical cell.
 As a result of its properties Nyex can undergo quick adsorption and fast electrochemical regeneration in a combined adsorption-electrochemical regeneration cell achieving 100% regeneration efficiency.
An electrochemical cell is a device capable of either generating electrical energy from chemical reactions or facilitating chemical reactions through the introduction of electrical energy.
 A common example of an electrochemical cell is a standard 1.5 - volt cell meant for consumer use.
 This type of device is known as a single galvanic cell.
 A "battery" consists of one or more cells, connected in either parallel or series pattern.
The Daniell cell is a type of electrochemical cell invented in 1836 by John Frederic Daniell, a British chemist and meteorologist, and consisted of a copper pot filled with a copper (II) sulfate solution, in which was immersed an unglazed earthenware container filled with sulfuric acid and a zinc electrode.
 He was searching for a way to eliminate the hydrogen bubble problem found in the voltaic pile, and his solution was to use a second electrolyte to consume the hydrogen produced by the first.
 Zinc sulfate may be substituted for the sulfuric acid.
 The Daniell cell was a great improvement over the existing technology used in the early days of battery development.
 A later variant of the Daniell cell called the gravity cell or crowfoot cell was invented in the 1860s by a Frenchman named Callaud and became a popular choice for electrical telegraphy.
Martin Ohm (May 6, 1792, Erlangen – April 1, 1872, Berlin) was a German mathematician and a younger brother of physicist Georg Ohm.

Question: Martin Ohm's brother was working at what profession when he began his research with the new electrochemical cell?
Answer: a school teacher