i·so·mer

(ī′sə-mər)

1. Chemistry Any of two or more substances that have the same molecular formula but differ in the way their atoms are connected to each other, in the spatial orientation of their atoms, or, in the case of large molecules such as DNA, in their molecular topology.

2. Physics Any of two or more nuclei with the same mass number and atomic number that have different radioactive properties and can exist in any of several energy states for a measurable period of time.

[Greek īsomerēs, having equal share : īso-, iso- + meros, part, share; see (s)mer- in Indo-European roots.]

i′so·mer′ic (-mĕr′ĭk) adj.

i′so·mer′i·cal·ly adv.

American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

isomer

(ˈaɪsəmə)

1. (Elements & Compounds) chem a compound that exhibits isomerism with one or more other compounds

2. (General Physics) physics a nuclide that exhibits isomerism with one or more other nuclides

isomeric adj

Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

i•so•mer

(ˈaɪ sə mər)

n.

a chemical compound or nuclide that displays isomerism.

[1865–70; < Swedish (1830) < Greek isomerḗs equally divided =iso- iso- + -merēs, adj. derivative of méos part, division]

i·so·mer

(ī′sə-mər)

One of two or more compounds composed of the same chemical elements in the same proportions but having a different arrangement of the atoms. Isomers differ from one another in at least one physical or chemical property. Lactose and sucrose are isomers.

The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

ThesaurusAntonymsRelated WordsSynonymsLegend:

Noun

isomer - a compound that exists in forms having different arrangements of atoms but the same molecular weight

chemical compound, compound - (chemistry) a substance formed by chemical union of two or more elements or ingredients in definite proportion by weight

Translations

Isomer

isomère

isomero

isomer

[ˈaɪsəməʳ] N → isómero m

Collins Spanish Dictionary - Complete and Unabridged 8th Edition 2005 © William Collins Sons & Co. Ltd. 1971, 1988 © HarperCollins Publishers 1992, 1993, 1996, 1997, 2000, 2003, 2005

isomer

n (Chem) → Isomer(e) nt

Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007

isomer

[ˈaɪsəməʳ] n → isomero

Collins Italian Dictionary 1st Edition © HarperCollins Publishers 1995

Mentioned in

References in periodicals archive

Table 1: Regression analysis of the plot of peak area versus concentration for each isomer Standard Sample Standard equation Alpha-tocopherol Y = 6.01[e.sup.6] X - 4.02[e.sup.6] Alpha-tocotrienol Y = 1.16[e.sup.7] X - 1.16[e.sup.7] Gamma-tocotrienol Y = 9.88[e.sup.6] X - 1.00[e.sup.7] Delta-tocotrienol Y = 1.86[e.sup.7] X - 2.15[e.sup.7] Correlation Standard Sample coefficient, [R.sup.2] Correlation, r Alpha-tocopherol 0.999812 0.999906 Alpha-tocotrienol 0.999904 0.999952 Gamma-tocotrienol 0.999711 0.999856 Delta-tocotrienol 0.998702 0.999351 Fig.

Supercritical fluid extraction of vitamin E from de-proteinised natural rubber (DPNR) serum

The PubChem databases for the alpha-Patchouli isomer were CID442384, CID521903, CID6432585, CID3080622, CID10955174, and CID56928117.

Binding energy calculation of Patchouli alcohol isomer cyclooxygenase complexes suggested as COX-1/COX-2 selective inhibitor

Rotational isomerism which leads to spectral changes of merocyanine monomers is one of the intriguing issues since it is often difficult to keep a molecular isomer in the frozen state for further manipulation.

Effect of concentration on isomerization of rhodanine derivatives of merocyanine dyes in polar solvents

Presence of the hydroxyethyl substituent could improve stability of open merocyanine isomer by obtaining of the cyclic oxazolidine isomers [20, 21].

Theoretical and experimental study of new photochromic bis-spiropyrans with hydroxyethyl and carboxyethyl substituents

The results are summarized in Table 3 and the major isomer is 4a (trans-isomer) [16,17].

Catalytic synthesis of pyrano- and furoquinolines using nano silica chromic acid at room temperature

Vitamin E is a fat soluble nutrient that exits in multiple isomer variants that have been shown to inhibit the development and progression of certain cancers by inhibiting mutational damage to DNA strands.

Vitamin-E found to significantly lower risk of developing liver cancer

Effect of surfactants on the absorption of 4 ug ml-1 aminophenol isomer products.

Simultaneous Spectrophotometric Determination of o-Aminophenol and p-Aminophenol Using H-Point Standard Addition Method -Application to Real Waters

This result was in agreement with experimental finding that in which 4R was the predominant isomer (4R:4S, >95%) [14].

DFT Studies on the Stereoselective Three-Component Ugi Reaction

It is primarily manufactured by the Fischer esterifaction of acetic acid and butanol isomer in the presence of catalytic sulfuric acid.

Know More Details on Butyl Acetate Market: Global Industry Analysis by 2021

The cis isomer of beta-carotene is more effective in treating vitamin A deficiency than the trans isomer.

CPD September 2018

* Isomer Partners LP, an existing subtenant which signed a new, direct 1,837 square-foot lease on a portion of the 26th floor;

The William Kaufman Organization (WKO) announced that it has signed six leases totaling approximately 14,948 s/f at 747 Third Avenue