n.

オキシダント、酸化体

関: oxidizing agent

WordNet

a substance that oxidizes another substance (同)oxidizer, oxidiser, oxidizing_agent
substance that inhibits oxidation or inhibits reactions promoted by oxygen or peroxides

PrepTutorEJDIC

オキシダント,酸化体
酸化防止剤;(ゴム・ガソリン・石けんの)劣化防止剤

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出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2014/04/21 06:08:14」(JST)

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European Union Chemical hazard symbol for oxidising agents

Dangerous goods label for oxidising agents

An oxidizing agent (also oxidant, oxidizer or oxidiser) is the element or compound in an oxidation-reduction (redox) reaction that accepts an electron from another species. Because the oxidizing agent is gaining electrons (and is thus often called an electron acceptor), it is said to have been reduced.

The oxidizing agent itself is reduced, as it is taking electrons onto itself, but the reactant is oxidized by having its electrons taken away by the oxidizing agent. Oxygen is the prime (and eponymous) example among the varied types of oxidizing agents.

Overview

The oxidizing agent takes electrons from another species, and thus itself is reduced.
The reducing agent gives electrons to another species, and thus itself is oxidized.
All atoms in a molecule can be assigned an oxidation number. This number changes when an oxidant acts on a substrate.
Redox reactions occur when oxidation states of the reactants change.

Example of oxidation

The formation of iron(III) oxide (rust) through the oxidation of iron;

4Fe + 3O₂ → 2Fe₂O₃

In the above equation, the iron (Fe) has an oxidation number of 0 before and 3+ after the reaction. For oxygen (O) the oxidation number began as 0 and decreased to 2−. These changes can be viewed as two (balanced) "half-reactions" that occur concurrently:

Oxidation half reaction: 4Fe → 4Fe³⁺ + 12e⁻
Reduction half reaction: 3O₂ + 12e⁻ → 6O²⁻

Iron (Fe) has become oxidised because its oxidation number increased and was the reducing agent because it gave electrons to the oxygen (O). Oxygen (O) has been reduced because the oxidation number has decreased and was the oxidising agent because it took electrons from iron (Fe).

Electron acceptor

Because the process of oxidation is so widespread (fire, explosives, chemical synthesis, corrosion), the term oxidising agent has acquired multiple meanings.

In one definition, an oxidising agent accepts - or gains - electrons. In this context, the reducing agent is called an electron donor. A classic oxidising agent is the ferrocenium ion [Fe(C₅H₅)₂]⁺, which accepts an electron to form Fe(C₅H₅)₂. Of great interest to chemists are the details of the electron transfer event, which can be described as inner sphere or outer sphere.

In more colloquial usage, an oxidising agent transfers oxygen atoms to the substrate. In this context, the oxidising agent can be called an oxygenation reagent or oxygen-atom transfer agent. Examples include [MnO₄]⁻ (permanganate), [CrO₄]²⁻ (chromate), OsO₄ (osmium tetroxide), and especially [ClO₄]⁻ (perchlorate). Notice that these species are all oxides, and are in fact polyoxides. In some cases, these oxides can also serve as electron acceptors, as illustrated by the conversion of [MnO₄]⁻ to [MnO₄]²⁻, manganate.

Dangerous materials definition

The dangerous materials definition of an oxidizing agent is a substance that is not necessarily combustible, but may, generally by yielding oxygen, cause or contribute to the combustion of other material.^[1] By this definition some materials that are classified as oxidising agents by analytical chemists are not classified as oxidising agents in a dangerous materials sense. An example is potassium dichromate, which does not pass the dangerous goods test of an oxidising agent.

The U.S. Department of Transportation defines Oxidizing agent specifically. There are two definitions for oxidizing agents governed under DOT regulations. These two are Class 5; Division 5.1 and Class 5; Division 5.2. Division 5.1 "means a material that may, generally by yielding oxygen, cause or enhance the combustion of other materials." Division 5.1 of the DOT code applies to solid oxidizers "if, when tested in accordance with the UN Manual of Tests and Criteria (IBR, see § 171.7 of this subchapter), its mean burning time is less than or equal to the burning time of a 3:7 potassium bromate/cellulose mixture." 5.1 of the DOT code applies to liquid oxidizers "if, when tested in accordance with the UN Manual of Tests and Criteria, it spontaneously ignites or its mean time for a pressure rise from 690 kPa to 2070 kPa gauge is less than the time of a 1:1 nitric acid (65 percent)/cellulose mixture."^[2]

Common oxidizing agents

Oxygen (O₂)
Ozone (O₃)
Hydrogen peroxide (H₂O₂) and other inorganic peroxides
Fluorine (F₂), chlorine (Cl₂), and other halogens
Nitric acid (HNO₃) and nitrate compounds
Sulfuric acid (H₂SO₄)
Peroxydisulfuric acid (H₂S₂O₈)
Peroxymonosulfuric acid (H₂SO₅)
Chlorite, chlorate, perchlorate, and other analogous halogen compounds
Hypochlorite and other hypohalite compounds, including household bleach (NaClO)
Hexavalent chromium compounds such as chromic and dichromic acids and chromium trioxide, pyridinium chlorochromate (PCC), and chromate/dichromate compounds
Permanganate compounds such as potassium permanganate
Sodium perborate
Nitrous oxide (N₂O)
Silver oxide (Ag₂O)
Osmium tetroxide (OsO₄)
Potassium nitrate (KNO₃), the oxidizer in black powder
Tollens' reagent
2,2'-Dipyridyldisulfide (DPS)

Common oxidizing agents and their products

Agent	Product(s)
O₂ oxygen	Various, including the oxides H₂O and CO₂
O₃ ozone	Various, including ketones, aldehydes, and H₂O; see ozonolysis
F₂ fluorine	F⁻
Cl₂ chlorine	Cl⁻
Br₂ bromine	Br⁻
I₂ iodine	I⁻, I₃⁻
ClO⁻ hypochlorite	Cl⁻, H₂O
ClO₃⁻ chlorate	Cl⁻, H₂O
HNO₃ nitric acid	NO nitric oxide NO₂ nitrogen dioxide
Hexavalent chromium CrO₃ chromium trioxide CrO₄²⁻ chromate Cr₂O₇²⁻ dichromate	Cr³⁺, H₂O
MnO₄⁻ permanganate MnO₄²⁻ manganate	Mn²⁺ (acidic) or MnO₂ (basic)
H₂O₂, other peroxides	Various, including oxides and H₂O

References

^ Australian Dangerous Goods Code, 6th Edition
^ 49 CFR 172.127 General Requirements for Shipments and Packagings; Subpart D

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English Journal

Polyphenolic pattern and in vitro cardioprotective properties of typical red wines from vineyards cultivated in Scafati (Salerno, Italy).

Tenore GC, Manfra M, Stiuso P, Coppola L, Russo M, Ritieni A, Campiglia P.SourceDepartment of Medicinal Chemistry, Università di Napoli Federico II, Via D. Montesano 49, 80131 Napoli, Italy. Electronic address: giancarlo.tenore@unina.it.
Food chemistry.Food Chem.2013 Oct 15;140(4):803-9. doi: 10.1016/j.foodchem.2012.10.023. Epub 2012 Nov 6.
Wines are the subject of increasing numbers of investigations owing to the pharmaceutical usefulness of grape phytochemicals. The aim of the present work was to hypothesize the use of lyophilised red wines for the formulation of food supplements potentially useful against both physiological and indu
PMID 23692769

Trans-ferulic acid-based solid lipid nanoparticles and their antioxidant effect in rat brain microsomes.

Trombino S, Cassano R, Ferrarelli T, Barone E, Picci N, Mancuso C.SourceDepartment of Pharmaceutical Sciences, University of Calabria, 87036 Arcavacata di Rende (CS), Italy.
Colloids and surfaces. B, Biointerfaces.Colloids Surf B Biointerfaces.2013 Sep 1;109:273-9. doi: 10.1016/j.colsurfb.2013.04.005. Epub 2013 Apr 22.
In this study, stearic acid- and stearyl ferulate-based solid lipid nanoparticles containing trans-ferulic acid (SLN-FA and SLN-SF-FA, respectively), were prepared and characterized for loading efficiency, size and shape. In addition, by using rat brain microsomes, we evaluated in vitro the antioxid
PMID 23668982

Oxidation matters: the ubiquitin proteasome system connects innate immune mechanisms with MHC class I antigen presentation.

Warnatsch A, Bergann T, Krüger E.SourceCharité-Universitätsmedizin Berlin, Charité CrossOver, Institut für Biochemie CCM, Berlin, Germany.
Molecular immunology.Mol Immunol.2013 Sep;55(2):106-9. doi: 10.1016/j.molimm.2012.10.007. Epub 2012 Nov 7.
During innate immune responses the delicate balance of protein synthesis, quality control and degradation is severely challenged by production of radicals and/or the massive synthesis of pathogen proteins. The regulated degradation of ubiquitin-tagged proteins by the ubiquitin proteasome system (UPS
PMID 23140834

Japanese Journal

Effect of Atomic-Layer-Deposition Method on Threshold Voltage Shift in AlGaN/GaN Metal--Insulator--Semiconductor High Electron Mobility Transistors

Ozaki Shiro,Ohki Toshihiro,Kanamura Masahito,Okamoto Naoya,Kikkawa Toshihide
Jpn J Appl Phys 52(11), 11NG04-11NG04-4, 2013-11-25
… In this study, atomic layer deposited (ALD)-Al<inf>2</inf>O<inf>3</inf>was used in AlGaN/GaN MIS-HEMTs as gate insulator films, and we focused on plasma-induced damages at the GaN/Al<inf>2</inf>O<inf>3</inf>interface, when O<inf>2</inf>plasma was used as the oxidant source for the ALD method. …
NAID 150000108077

Oxidation of N-Alkyl-N-(3-carboxypropyl)nitrosamines by Iron Porphyrin and Oxidant Forms Alkylating Mutagens

Inami Keiko,Yasui Hiroki,Tsugumi Hirotaka [他]
Genes and environment : the official journal of the Japanese Environmental Mutagen Society 35(4), 99-104, 2013-11
NAID 40019868021

Green Asymmetric Oxidation Using Air as Oxidant (Special Issue in English)

Uchida Tatsuya,Katsuki Tsutomu
有機合成化学協会誌 71(11), 1126-1135, 2013-11
NAID 40019859572

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