All articles starting with N
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Nitric oxide
Nitric oxide (NO) is a colorless diatomic gas and free radical that regulates blood vessel tone and is the first step of nitric acid production.
Nitric oxide synthase
Nitric oxide synthase, or NO synthase, is an enzyme family that makes nitric oxide from L-arginine; its three mammalian isoforms regulate blood vessels, nerves, and immune defense.
Nitric oxide-releasing nanoparticles
Nitric oxide-releasing nanoparticles are nanoscale drug-delivery vehicles that store nitric oxide donors and release the gas at target tissues, addressing its extremely short half-life and imprecise delivery.
Nitridation
Nitridation is the treatment of silicon or silicon dioxide surfaces in a nitrogen-bearing ambient, such as ammonia, to form silicon nitride or nitrided gate oxides in semiconductor manufacturing.
Nitride
A nitride is an inorganic compound in which nitrogen is the N3− anion, classified as ionic, covalent, or interstitial, and used in hard coatings like titanium nitride.
Nitride halide
A nitride halide is a mixed-anion inorganic compound containing nitride and halide ions in one crystal lattice, best known as layered MNX phases of titanium, zirconium, and hafnium.
Nitriding
Nitriding is a thermochemical heat treatment that diffuses nitrogen into the surface of steel to form hard nitrides, developed in the early 20th century by Machlet and Fry.
Nitrification
Nitrification: microbial oxidation of ammonia to nitrite then nitrate, by AOB (Nitrosomonas), NOB (Nitrobacter), archaea, and comammox Nitrospira; central to the nitrogen cycle, wastewater treatment, and N2O emissions.
Nitrifying bacteria
Nitrifying bacteria, also known as nitrate-producing bacteria, are bacteria that gain energy by aerobically oxidizing ammonia to nitrate via nitrite, driving nitrification in soils and wastewater treatment.
Nitrilase
Nitrilase (EC 3.5.5.1) is a thiol enzyme that hydrolyzes nitriles directly to carboxylic acids and ammonia, produced by plants, bacteria, and fungi and used to make acids and clean up cyanide.
Nitrile
A nitrile, also called a carbonitrile, is an organic compound carrying a strongly polarized cyano group, −C≡N, found in solvents like acetonitrile, polymers, superglues, and medicines.
Nitrile anion
A nitrile anion is a stabilized carbanion formed by deprotonating the carbon adjacent to a nitrile group, widely used in organic synthesis to form carbon–carbon bonds.
Nitrile imine-mediated tetrazole–ene cycloaddition
Nitrile imine-mediated tetrazole–ene cycloaddition (NITEC) is a photoinduced click reaction in which light converts a tetrazole into a nitrile imine that cycloadds to an alkene, giving a fluorescent pyrazoline linkage.
Nitrile oxide
A nitrile oxide is a reactive organic functional group of formula R–C≡N⁺–O⁻, a nearly linear 1,3-dipole usually generated in situ and trapped in cycloadditions that build isoxazoles and isoxazolines for synthesis and medicinal chemistry.
Nitrile reduction
Nitrile reduction is the chemical conversion of an organic nitrile into a primary amine or, with partial reduction, an aldehyde, and is a major route to amines.
Nitrile rubber
Nitrile rubber, also known as Buna-N, is a synthetic rubber copolymer of acrylonitrile and butadiene, valued for oil and fuel resistance in seals, hoses, and gaskets.
Nitrilotriacetic acid
Nitrilotriacetic acid (NTA), also called nitrilotriacetate, is a synthetic aminopolycarboxylic acid used chiefly as a chelating agent for metal ions and as a builder in laundry detergents, and is classified as possibly carcinogenic.
Nitrite
Nitrite (NO2−) is the nitrogen oxoanion, the conjugate base of nitrous acid, formed in the nitrogen cycle and used as sodium and potassium salts to cure meat.
Nitro (Six Flags Great Adventure)
Nitro is a Bolliger & Mabillard steel hypercoaster at Six Flags Great Adventure, Jackson, New Jersey, opened 2001: 230 feet tall, 215-foot 66-degree drop, near 80 mph, 5,394 feet of track, first B&M coaster with magnetic brakes.
Nitro blue tetrazolium chloride
Nitro blue tetrazolium chloride (NBT) is a yellow tetrazolium salt reduced to a blue formazan, used in histochemistry and the NBT test for chronic granulomatous disease.
Nitro Circus
Nitro Circus, action sports entertainment brand co-founded by Travis Pastrana in 2003, live FMX and BMX stunt shows, MTV series from 2009, over 3 million tickets sold, Nitro Circus 2.0 Tour in 2026.
Nitro compound
A nitro compound is an organic molecule bearing the nitro group, –NO₂, valued in synthesis because it reduces readily to amines; the simplest is nitromethane, and multiple nitro groups often make compounds explosive.
Nitroanisole
Nitroanisole is the name for the three positional isomers of nitro-substituted anisole, each with formula C₇H₇NO₃; the ortho isomer is commercially important and a listed carcinogen.
Nitrobacter
Nitrobacter, a genus of gram-negative alphaproteobacteria (Winogradsky 1892) that oxidize nitrite to nitrate in nitrification; facultative chemolithoautotrophs using the Calvin cycle, r-strategists with low nitrite affinity, historically the model nitrite oxidizer before Nitrospira was found to dominate.
Nitrobenzaldehyde
Nitrobenzaldehyde is any of the three positional isomers of nitro-substituted benzaldehyde, C₇H₅NO₃, made by nitrating benzaldehyde and used to synthesize dyes, pesticides, and pharmaceuticals; the ortho isomer is also a photochemical actinometer.
Nitrobenzene
Nitrobenzene, also known as oil of mirbane, is a synthetic oily liquid with an odor of bitter almonds, produced from benzene and used almost entirely to make aniline.
Nitrobenzoic acid
Nitrobenzoic acid refers to three positional isomers of mononitro-substituted benzoic acid, C₇H₅NO₄, crystalline solids used as intermediates in synthesis, including the anesthetics procaine and benzocaine.
Nitrobenzoxadiazole
Nitrobenzoxadiazole (NBD), systematically 7-nitro-2,1,3-benzoxadiazole, is a small environmentally sensitive fluorophore first reported in 1968, now widely used as a scaffold for fluorescent probes sensing analytes such as hydrogen sulfide.
Nitrocellulose
Nitrocellulose, also called cellulose nitrate or guncotton, is a nitrate ester of cellulose first made by Schönbein in 1846, used in lacquers, plastics, membranes, and gun propellants.
Nitrocellulose membrane
A nitrocellulose membrane is a porous cellulose nitrate sheet that binds proteins, DNA, and RNA, serving as the standard support in Western, Southern, and Northern blotting.