| 释义 |
▪ I. spacer1|ˈspeɪsə(r)|
[f. space v. + -er1.]
1. a. A device or piece of mechanism for spacing words; a piece of metal, etc., for making a space, interval, or division.
1884Knight Dict. Mech. Suppl. 911/2 By touching now the justifying-key, he caused the spacer to draw the line into another part of the [type-composing] machine to be justified. 1904in Cent. Dict. Suppl. s.v., These ventilating spaces are obtained by means of metal spacers. 1916Chambers's Jrnl. July 480/1 A new unit in roofing called a spacer allows of ordinary plain tiles or slates being laid wider apart than usual. 1943Sun (Baltimore) 15 Apr. 26/3 She figured out a way to save countless man-hours in the manufacture of spacers—small rubber rings used in Rolls Royce airplane engines. 1954Automobile Engineer XLIV. 508/3 A tubular spacer and two thrust washers round the shaft separate the roller bearings. 1962Which? July 197/2 The second type [of life-jacket]..used sealed-in air between inner and outer coverings..which are held apart by ‘spacers’ of absorbent foam plastic. 1976Shooting Mag. Dec. 12 (Advt.), It's a quality production gun, with one major difference. You can adjust the stock and insert various ‘spacers’ to achieve the perfect cast and drop.
b. Archæol. In full, spacer plate. A flat bead perforated with several holes in the same plane, by which the threads of a primitive multi-strand necklace are held apart.
1924D. Randall-MacIver Villanovans & Early Etruscans vi. 173 Fusiform and spherical gold beads, white and blue glass cylinders and small perforated spacers of amber formed the other elements of the necklace. 1940V. G. Childe Prehist. Communities of British Isles vii. 124 In Ireland..the crescentic necklace was translated into a crescentic collar, cut out of a sheet of native gold and relieved with designs in panels, imitating the spacer-plates of the necklaces. 1958Antiquity XXXII. 209 The complex-bored amber spacers from Hagenau. 1980J. J. Taylor Bronze Age Gold Work iii. 41 The spacer-plate motif can be found in the Beaker repertoire pre-dating Wessex, to which the earliest dated spacer-plate is likely to belong.
2. One who or that which spaces, or allows space, in a particular manner.
1888Encycl. Brit. XXIV. 698/2 It [the cylindrical typewriting machine] is a variable spacer, giving more space to..m and w than to..i, t, and l.
3. Biol. A section of DNA which is not represented in the final RNA transcript, separating two sections which are.
1970O. L. Miller et al. in Cold Spring Harbor Symp. Quantitative Biol. XXXV. 505/2 Non-matrix segments of varying lengths (spacers) are intercalated between matrix units. 1974New Scientist 9 May 329 Chemists..have succeeded in synthesising a nucleotide complementary to a definite part of a small bacteriophage.., a part regarded as a spacer. 1982W. I. P. Mainwaring et al. Nucleic Acid Biochem. & Molecular Biol. vii. 258 There are spacer regions between genes which may or may not be transcribed. If transcribed, their contribution to the RNA transcript is removed by an excision process during the maturation of the RNA.
4. Special Comb.: spacer gel, a part of the gel used in electrophoresis (see quot. 1975).
1968J. R. Sargent Methods in Zone Electrophoresis vii. 90 It is possible to eliminate the sample gel and the spacer gels..and to apply the sample directly on top of the main gel. 1975Davis & Simpkins in Williams & Wilson Biologist's Guide to Princ. & Techniques Pract. Biochem. iv. 115 The upper third of the gel consists of a large pore ‘stacking’ or ‘spacer’ gel, and the lower portion of smaller pore ‘running’ or ‘separating’ gel. The function of the stacking gel is to concentrate the sample as it moves through the gel, so that on entering the running gel it is an extremely narrow band.
▸ Med. A tube or chamber that is placed by the user between a pressurized aerosol inhaler and his or her mouth in order to improve delivery of a measured dose of the drug.
1979Brit. Med. Jrnl. 8 Dec. 1479/1 The interposition of a tube spacer between the aerosol and the mouth reduces the deposition of drug. 1989European Respiratory Jrnl. 2 377 Equally effective bronchodilatation may be obtained with metered-dose inhalers combined with valved spacers. 2001Times 24 Apr. ii. 10/2 Recent evidence suggests that five to ten puffs from a conventional inhaler through a ‘spacer’ bottle will help to ease his breathing.
▪ II. spacer2 Science Fiction.|ˈspeɪsə(r)|
[f. space n.1 + -er1.]
1. = spaceman 2.
1955C. M. Kornbluth Mindworm 59 ‘I'm a spacer,’ he said... ‘Venus.’ 1958I. Asimov Naked Sun i. 11 The Galaxy was closed to Earthmen. It was pre-empted by the Spacers, whose ancestors had been Earthmen centuries before.
2. A spaceship, spacecraft.
1962New Worlds Sci. Fiction Sept. 50 The spacer broke through the low hanging layer of clouds above. 1978D. R. Mason Mission to Pactolus R i. 5 A Fingalnan voice spoke into the quiet command cabin of the hurrying spacer. |