Nitrogen
Element 7 · chemical symbol: N
These Vrulum profiles mention Nitrogen by name. Read each profile for its specific context; a mention alone does not establish composition, performance or use of the pure element.
For periodic-table data and other properties, consult the Royal Society of Chemistry periodic table.
Related technology profiles
Catalytic converters
A catalytic converter is a device in a petrol car's exhaust that uses a catalyst to turn carbon monoxide, unburnt fuel and nitrogen oxides into less harmful gases. It has been fitted to new petrol cars in the United States since the mid-1970s, and it depends on lead-free petrol.
Crops with boosted photosynthesis
Plant scientists are engineering crops to waste less light energy and carbon, either by recovering faster from the protective heat release that follows shade or by bypassing photorespiration. Several replicated field trials report yield or biomass gains, but the soybean yield result is disputed and no independent multi-site replication is confirmed in the sources reviewed.
Hydrogen aircraft
Hydrogen aircraft would use hydrogen either in a fuel cell that drives electric propellers or in a modified gas turbine. Engine and fuel-cell tests, an uncrewed drone flight and airport ground trials have taken place, but no hydrogen passenger aircraft has entered service and the climate benefit depends on how the hydrogen is made.
Magnetic levitation
Magnetic levitation uses magnetic forces to support an object without contact. Maglev trains and laboratory demonstrations show that it works, but stable support usually depends on a purpose-built track or supporting structure, so it is not the same as a free-floating board.
Nitrogen-fixing cereals
Nitrogen-fixing cereals would take nitrogen from the air through engineered plants or root-associated microbes, reducing the need for synthetic fertiliser. Some commercial microbial products are sold for maize, but their field results vary, and engineering cereals to fix nitrogen themselves has so far only reached early laboratory steps.
Perennial grains
Perennial grains are cereal crops that live for several years and regrow from the same roots, so farmers do not have to replant them every season. Kernza and perennial rice are the best-documented examples, but yields tend to fall as stands age and soil carbon gains have not been shown at scale.
Petroleum refining
Petroleum refining separates crude oil into fractions and changes their molecules to make petrol, diesel, jet fuel and lubricating oils. Its key steps ran from early kerosene stills to catalytic cracking in the 1930s. EPA reports that refinery sulphur dioxide and nitrogen oxide emissions have fallen since 2000.