R

听听怎么读

英 [ɑ:(r)]

美 [ɑr]

是什么意思

英语字母表的第18个字母；

英英释义

R[ ɑ: ]

n.
- a unit of radiation exposure; the dose of ionizing radiation that will produce 1 electrostatic unit of electricity in 1 cc of dry air
  同义词：roentgen
- (physics) the universal constant in the gas equation: pressure times volume = R times temperature; equal to 8.3143 joules per kelvin per mole
  同义词：gas constantuniversal gas constant
- the 18th letter of the Roman alphabet
  同义词：letter r
- the length of a line segment between the center and circumference of a circle or sphere
  同义词：radius

学习怎么用

词组短语

r and d abbr. 研究发展（Research and Development）

r wave非线性波

双语例句

The trilled `r' is produced by vibrating the tongue against the upper teeth.
发带颤音的r，舌抬向上齿颤动而成。

权威例句

Covering system
Cancer statistics, 2010.
Protein Measurement With Folin Fenol Reagent
W.R. Grace & Co. v. EPA: An Arbitrary Outcome
Protein measurement with the Folin phenol reagent.
System and method for providing even heat distribution and cooling return pads
Epidémiologie de la luxation congénitale de hanche dans la région Languedoc-Roussillon
AR-GE HARCAMALARI VE İLERİ TEKNOLOJİ MAL İHRACATI İLİŞKİSİ: PANEL NEDENSELLİK ANALİZİ THE RELATIONSHIP BETWEEN R&D EXPEN...
Psychological Methods of Healing. By William Brown, D.M., D.Sc, F.R.C.P. (London, University of Lon...
The Romance of Treasure Trove. By Charles R. Beard (with an introduction and one chapter by Ronald A. Co...

r开头的单词