| 释义 |
up-stream, adv. (n.) and a.
Also up stream, upstream.
[up prep.2 2, 6.]
A. adv.
1. a. In a direction contrary to the flow of a stream; higher up or along a stream.
Common from c 1890. Properly as two words, stressed up-ˈstream, except when contrasted with down-stream. In recent use also const. of or from (a place).
1681Robertson Phraseol. Gen. 1282 To go up stream, adverso flumine navigare. 1839Longfellow Hyperion i. viii. (1844) 58 The rising tide bears against the rushing torrent up stream, and pushes back the hurrying waters. 1849Cupples Green Hand xvi, The sound of a loud rush of water up-stream broke upon us. 1889Jerome Three Men in Boat ix. 142 Three or four miles up stream is a trifle, early in the morning.
b. quasi-n. A position or place further up a stream.
1891Nature 18 June 152/2 From upstream of it are derived three main trunk canals. 1915I. H. Evans in Man XV. 25 A spot some two miles to the up-stream of the Tamu ground.
2. In the oil and gas industries: at or towards the source of production; spec. at a stage in the process of extraction and production before the raw material is ready to be refined.
1973Auckland Star 10 Feb. 18 The most natural way the oil producers can spend their vast wealth..is in developing the industry itself. Huge investment is needed ‘upstream’. 1983Business Week 21 Feb. 61/1 KPC has not neglected foreign activities upstream. It wants to expand exploration in the U.S.
B. adj. (ˈup-stream.)
1. Situated farther or higher up a stream.
1838Civil Eng. & Arch. Jrnl. I. 150/1 The up-stream angles of the dam. 1843Ibid. VI. 88/1 [A] deposit accumulated largely on the up-stream side. 1875Knight Dict. Mech. 1084/2 The up-stream end of a canal-lock.
2. Directed, taking place, up-stream.
1826J. F. Cooper Mohicans iii, They call this up-stream current the tide. 1889Science-Gossip XXV. 209/2 There is an up-stream migration of elvers in the spring. 1894Field 9 June 832/1 Many experienced anglers do not like an up⁓stream wind for..dun hatchings.
3. U.S. Difficult, troublesome. rare—1.
1847J. Brown in Boston Public Library Bulletin May (1900) 177, I do not wish any upstream measure taken to supply funds.
4. Relating to the stages in the production of oil and gas before the raw material is ready for refining.
1965Williams & Meyers Oil & Gas Terms (ed. 2) 429 Gathering activities are..ended when gas reaches a central point... Facilities used before this point of demarcation are upstream facilities. 1981Times 3 Apr. 17/1 Upstream activities..are overshadowed by the comfortable world supply position while downstream, weak demand is making it more difficult to recoup rising operating costs.
Add:[A.] 3. Biol. In the direction opposite to that in which transcription occurs. Opp. *downstream adv. 2.
1977D. F. Klessig in Cell XII. 9 (heading) Two adenovirus mRNAs have a common 5′ terminal leader sequence encoded at least 10 kb upstream from their main coding regions. 1979Cell XVIII. 569 The DNA sequence upstream from the cap, the region of the potential promoter site does not..contain a ‘TATAAA’-type homology. 1988Mouse News Let. Nov. 97 A gene which shows tissue-specific regulation..has some specific sites of methylation correlated with expression more than 12 kb upstream to the first exon. |