| 释义 |
penetrant, a. (n.)|ˈpɛnɪtrənt|
[ad. L. penetrānt-em, pr. pple. of penetrāre to penetrate, or F. pénétrant ppl. a. (13–14th c. in Hatz.-Darm.).]
A. adj. That penetrates; penetrating.
1. lit. Having the property of penetrating, piercing, or making its way into anything.
1543Traheron Vigo's Chirurg. ii. iv. i. 68 Thys Aposteme is penetrant or persynge. 1601Holland Pliny II. 87 Their sent is piercing and penetrant. 1713Derham Phys.-Theol. 29 It's Rays would be less penetrant. 1887R. Garnett Carlyle vii. 126 The hit was fair and penetrant.
2. fig. in reference to the mind, intellect, etc.: Having or showing mental penetration or insight; acute; subtle: = penetrating ppl. a. 3.
1599Sandys Europæ Spec. (1632) 41 So searching and penetrant is the cunning of that Sea [= See]. 1661Boyle Style of Script. (1675) 188 Whose penetrant and powerful arguments defeat not God's enemies. a1734North Lives (1826) II. 145 His skill was more pedantic than penetrant. 1836W. A. Butler in Blackw. Mag. XXXIX. 455 He who hath The vision penetrant of Poesie.
3. Genetics. Producing in the phenotype the characteristic effect of the gene or combination of genes.
1955R. B. Goldschmidt Theoret. Genetics iii. v. 379 An incompletely penetrant effect is often based upon a system of multiple factors. 1973B. J. Williams Evolution & Human Origins ii. 30/1 Genes are spoken of as fully penetrant or incompletely penetrant, but this is, in fact, as much a property of the environment as of the gene. 1978Nature 27 Apr. 755/1 Gajdusek originally suggested that transmission was due to an autosomal dominant gene, fully penetrant in heterozygous females, but rarely penetrant in males unless they were homozygous.
†B. n.
1. A person of penetration or insight. Obs. rare.
a1734North Exam. i. ii. §173 (1740) 121 Our Penetrants have fancied all the Riddles..which in the Reign of King Charles II. were many, came N.N.E.
2. A penetrating coloured or fluorescent liquid used in a technique for detecting surface defects, in which the liquid is applied to the surface, excess removed, and developer applied to bring out the liquid left in the cracks and pores. Freq. attrib., as penetrant inspection, penetrant testing.
1951Materials & Methods Feb. 92/2 Fluorescent penetrant inspection makes use of a water-washable penetrant of high fluorescence and unusual wetting or penetrating properties. 1958H. Etherington Nucl. Engin. Handbk. x. 152 Penetrant-inspection methods are applicable to all metals as well as glazed ceramics, plastics, and other non⁓porous materials. Ibid., The penetrant is drawn into surface discontinuities by capillary action. 1959J. F. Hinsley Non-Destructive Testing xiv. 323 (caption) Crack in casting flange revealed by fluorescent penetrant. 1973A. Parrish Mech. Engineer's Ref. Bk. viii. 13 Penetrant testing is the modern version of the old oil and whiting technique and is applicable to all metals and many non-metallic materials. 1975Bram & Downs Manuf. Technol. ii. 67 Inspection with penetrant is probably the oldest of the major non-destructive testing methods in use today. Ibid., The surface of the component is examined in order to locate the penetrant indications which have been formed in the developer coating. 1977Hot Car Oct. 58/2 One wheel per batch is pressure tested and a percentage of the batch is checked by a penetrant dye for porosity. |