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    1. helium

      英 ['hi?l??m] 美['hil??m]
      • n. [化學(xué)] 氦(符號(hào)為He,2號(hào)元素)

      暢通詞匯TEM8IELTSTOEFL低頻詞

      助記提示


      1. hel- / heli- "sun" + -ium.
      2. 因?yàn)樵撛刈畛跏窃谌帐称陂g從太陽(yáng)光譜中探測(cè)出來(lái)的,因此就取了這個(gè)名字,-ium 本是用于金屬元素的后綴,由于該元素最初被認(rèn)為是一種堿金屬,所以就使用了這個(gè)后綴。

      中文詞源


      helium 氦,氦氣

      來(lái)自希臘語(yǔ)helios,太陽(yáng)。因這種元素發(fā)現(xiàn)于太陽(yáng)光譜中而得名。

      英文詞源


      helium (n.)
      1868, coined from Greek helios "sun" (see sol), because the element was detected in the solar spectrum during the eclipse of Aug. 18, 1868, by English astronomer Sir Joseph N. Lockyer (1836-1920) and English chemist Sir Edward Frankland (1825-1899). It was not actually obtained until 1895; it was assumed before that to be an alkali metal, hence the ending in -ium.

      雙語(yǔ)例句


      1. Helium is a very light gas.
      氦是一種非常輕的氣體。

      來(lái)自柯林斯例句

      2. Helium is a gas used in balloons.
      氦是一種用于氣球的氣體.

      來(lái)自《現(xiàn)代漢英綜合大詞典》

      3. Unlike helium - 4, it cannot be produced by radioactive decay.
      與氦 - 4不同之處是, 氦-3不能由放射性衰變產(chǎn)生.

      來(lái)自英漢非文學(xué) - 科技

      4. The helium - 3 apparently became trapped when the earth was formed.
      顯然,當(dāng)?shù)厍蛐纬蓵r(shí),氦 - 3就被圈閉了.

      來(lái)自英漢非文學(xué) - 科技

      5. After hydrogen, the atom with the simplest structure is that of helium.
      在氫元素之后, 氦的原子結(jié)構(gòu)最簡(jiǎn)單.

      來(lái)自辭典例句