All articles starting with N
16,460 articles
Nitrogen-centered radical cation chemistry
Nitrogen-centered radical cation chemistry studies cationic radical species with the charge and unpaired electron on nitrogen, especially amine radical cations formed by one-electron oxidation of amines.
Nitrogen-centered radical-mediated C(sp3)–H amination
Nitrogen-centered radical-mediated C(sp3)–H amination is a strategy for converting carbon–hydrogen bonds into carbon–nitrogen bonds, where a nitrogen-centered radical abstracts a hydrogen atom to generate a carbon radical.
Nitrogen-doped graphene ORR catalyst
A nitrogen-doped graphene ORR catalyst is graphene doped with nitrogen atoms to catalyze the oxygen reduction reaction, the cathode reaction of fuel cells and metal-air batteries, without any metal.
Nitrogen-vacancy center
The nitrogen-vacancy center, or NV center, is a diamond defect of a nitrogen atom beside a missing carbon atom, a leading platform for quantum sensing and magnetometry.
Nitrogen-vacancy center nanoscale NMR
Nitrogen-vacancy center nanoscale NMR (NV-NMR) is NMR spectroscopy in which nitrogen-vacancy color centers in diamond serve as atomic-sized magnetic sensors, detecting signals from volumes down to a single molecule, first demonstrated in 2013.
Nitrogen-vacancy electron spin resonance
Nitrogen-vacancy electron spin resonance (NV-ESR) detects electron spin resonance spectra using nitrogen-vacancy centers in diamond, sensing spins within a few to a few tens of nanometers and enabling room-temperature, optically read nanoscale spectroscopy.
Nitrogen-vacancy magnetometry
Nitrogen-vacancy magnetometry is a quantum sensing technique that uses nitrogen-vacancy defects in diamond to map magnetic fields from nanometers to millimeters, including imaging magnetization of rocks and meteorites.
Nitrogenase iron protein NifH
NifH, the nitrogenase iron protein (dinitrogenase reductase), is a nifH-encoded homodimer with a [4Fe-4S] cluster that transfers electrons to NifDK, hydrolyzes MgATP, and aids FeMoco and P-cluster biosynthesis; homologs VnfH and AnfH serve alternative nitrogenases.
Nitrogenase molybdenum-iron cofactor biosynthesis protein
Nitrogenase molybdenum-iron cofactor biosynthesis proteins (NifEN, NifB, NifU, NifS, NifV, NifX, NafY) assemble FeMoco, nitrogenase's N2-reducing active site, on scaffolds before insertion into the MoFe protein.
Nitrogenase molybdenum-iron protein alpha chain
NifD, the nitrogenase molybdenum-iron protein alpha chain (nifD gene, UniProt P07328), is the 492-residue alpha subunit of the alpha2beta2 MoFe dinitrogenase tetramer; it cradles the FeMo-cofactor active site via conserved alpha-Cys275 and alpha-His442 ligands.
Nitroglycerin
Nitroglycerin, also called glyceryl trinitrate, is a powerful liquid explosive discovered in 1847 that Alfred Nobel used in dynamite and that treats angina in diluted form.
Nitroimidazole
A nitroimidazole is an imidazole ring bearing a nitro group, a chemical scaffold behind antimicrobial and antiparasitic drugs, best known in metronidazole, and studied as radiosensitizers.
Nitromethane
Nitromethane (CH3NO2), also sold as Nitrocarbol, is the simplest nitroalkane, a colorless oily liquid serving as an industrial solvent, explosive, and fuel for drag racing and model engines.
Nitrone
A nitrone is the N-oxide of an imine, a 1,3-dipolar compound known since 1890, used in cycloaddition synthesis and as a spin trap for detecting radicals.
Nitrophenols
Nitrophenols are phenols carrying one or more nitro groups, chiefly the three isomers 2-, 3-, and 4-nitrophenol, industrial intermediates for dyes and pesticides that form in vehicle exhaust and degrade in soil and water.
Nitropyrene
Nitropyrene is a nitrated polycyclic aromatic hydrocarbon formed chiefly in diesel engine exhaust, where the isomer 1-nitropyrene is the most abundant nitroarene and is classified as probably carcinogenic to humans.
Nitroreductase
Nitroreductase (NTR), bacterial flavoenzyme family (NfsA, NfsB) reducing nitroaromatics with NAD(P)H via ping-pong bi-bi mechanism; type I oxygen-insensitive, type II oxygen-sensitive; used in prodrug cancer therapy, bioremediation, biocatalysis.
Nitrosamine
Nitrosamines (N-nitrosamines) are organic compounds in which a nitroso group is attached to an amine nitrogen; many are potent carcinogens, and trace contamination of drugs has caused widespread recalls since 2018.
Nitrosamine formation chemistry
Nitrosamine formation chemistry is the set of reactions by which carcinogenic N-nitroso compounds form when nitrite-derived nitrosating agents react with amines in drugs, cured meats, and water.
Nitrosation
Nitrosation is a chemical reaction that introduces a nitroso group (–N=O) into organic molecules, most often amines, phenols, and enols; on secondary amines it gives carcinogenic N-nitrosoamines.
Nitroso
Nitroso, or the nitroso group, is the functional group –NO attached to carbon or another element; aromatic members dimerize and N-nitroso amines can be carcinogens.
Nitrosoguanidine
Nitrosoguanidine (N-nitrosoguanidine) is a crystalline nitroso derivative of guanidine, an initiating explosive supplied wetted with about 20% water and the parent compound of the widely used mutagen MNNG.
Nitrosomonas
Nitrosomonas: genus of gram-negative chemolithoautotrophic ammonia-oxidizing bacteria (family Nitrosomonadaceae) that oxidize NH3 to nitrite via AMO and HAO; type species N. europaea, first JGI bacterial genome.
Nitrosomonas europaea
Nitrosomonas europaea, type species of Nitrosomonas (Winogradsky 1892, txid915), a gram-negative obligate chemolithoautotrophic ammonia-oxidizing bacterium converting NH3 to nitrite via AMO and HAO; first JGI bacterial genome, model AOB producing NO and N2O.
Nitrosopumilus
Nitrosopumilus is a genus of marine ammonia-oxidizing archaea (Thaumarchaeota, Nitrosopumilaceae); its type species N. maritimus SCM1, first AOA isolated (2005), oxidizes ammonia to nitrite with Km ≈ 133 nM and fixes CO2.
Nitrososphaera
Nitrososphaera is a genus of spherical, ammonia-oxidizing archaea in the class Nitrososphaeria (phylum Nitrososphaerota, formerly Thaumarchaeota), type species N. viennensis from Vienna garden soil, first soil AOA in pure culture.
Nitrosourea
Nitrosourea is a compound containing both a nitroso group and a urea group, a class best known for alkylating anticancer drugs such as carmustine and lomustine.
Nitrothal
Nitrothal (nitrothal-isopropyl, CAS 10552-74-6) is a non-systemic contact fungicide introduced circa 1975 by BASF for powdery mildew and scab on fruit crops; not approved in the EU or UK, still used in Australia, South Africa, and New Zealand.
Nitrotoluene
Nitrotoluene, also called methylnitrobenzene, is any of three isomeric nitroaromatic compounds with formula C₇H₇NO₂, produced by nitrating toluene; the ortho and para isomers are important dye intermediates.
Nitrous acid
Nitrous acid (HNO₂, HONO) is a weak, unstable nitrogen acid that exists only in solution or gas, used in diazotization and driving atmospheric hydroxyl radical formation.