请输入您要查询的英文单词:

 

单词 octavalent
释义

octavalentadj.n.

Brit. /ˌɒktə(ʊ)ˈveɪlənt/, /ˌɒktə(ʊ)ˈveɪln̩t/, U.S. /ˌɑktəˈveɪl(ə)nt/
Forms: 1800s– octavalent, 1800s– octovalent.
Origin: Formed within English, by compounding. Etymons: octo- comb. form, -valent comb. form.
Etymology: < octo- comb. form + -valent comb. form; in later use as octavalent remodelled after octa- comb. form (see discussion s.v. octo- comb. form). Compare French octovalent (1879 in the passage translated in quot. 1880 at sense A. 1).
Chemistry.
A. adj.
1. Chemistry. Having a valency of eight.
ΘΚΠ
the world > matter > chemistry > valency > [adjective] > having a valency of eight
octavalent1868
1868 H. B. Jones & H. Watts Fownes's Man. Elem. Chem. (ed. 10) 570 These hydrocarbons..might be expected to act as octovalent, sexvalent, quadrivalent, or bivalent radicals.
1880 E. Cleminshaw tr. C. A. Wurtz Atomic Theory 233 In perruthenic acid and in osmic acid..ruthenium and osmium act as octovalent elements.
1899 Science 28 Apr. 612/1 It [sc. potassium chloroplatinate] may be K2PtCl4, with octavalent platinum.
1908 Proc. Royal Soc. 1907–8 A. 80 382 Platinum is an octovalent element.
1950 N. V. Sidgwick Chem. Elements II. 1458 There are a fair number of octovalent osmium compounds.
1973 S. E. Livingstone in J. C. Bailar et al. Comprehensive Inorg. Chem. III. xliii. 1209 The octavalent state [of osmium] is more stable than that of ruthenium.
2. Genetics. Designating a multivalent association of eight chromosomes.
ΚΠ
1951 Evolution 5 147 (caption) 5 bivalents, 1 octavalent chain.
1970 Bot. Gaz. 131 216/1 The occurrence of hexavalent and octovalent associations in the E. agropyroides X A. subsecundum hybrid merely follows an established pattern.
3. Immunology. Having eight combining sites or epitopes.
ΚΠ
1975 Proc. National Acad. Sci. U.S.A. 75 3846/1 Using this octavalent form of the viral spikes as our major tool.
1991 Science 11 Oct. 287/3 The positive attributes of the octavalent immunogens should greatly facilitate the development of a subunit AIDS vaccine.
B. n.
Genetics. A multivalent association of eight chromosomes.
ΚΠ
1946 Amer. Jrnl. Bot. 33 613/1 The relative fequencies of octovalents and sexivalents were much higher than were found in octoploid Petunia.
1953 Bull. Torrey Bot. Club 80 114 The multivalent associations..are as follows: (1) two quadrivalents and two hexavalents; (2) one octavalent.
1982 Amer. Jrnl. Bot. 69 489/2 Circle quadrivalent, hexavalent, and octavalent with 4, 6, and 8 chiasmata respectively.
1993 Internat. Jrnl. Plant Sci. 154 456 The chromosome complement contains two octasomes capable of synapsing simultaneously to form octavalents.
This entry has been updated (OED Third Edition, March 2004; most recently modified version published online March 2022).
<
adj.n.1868
随便看

 

英语词典包含1132095条英英释义在线翻译词条,基本涵盖了全部常用单词的英英翻译及用法,是英语学习的有利工具。

 

Copyright © 2004-2022 Newdu.com All Rights Reserved
更新时间:2024/9/20 23:49:52