| 释义 |
Definition of helium in English: heliumnoun ˈhiːlɪəmˈhiliəm mass nounThe chemical element of atomic number 2, an inert gas which is the lightest member of the noble gas series. 氦（符号： He ） Helium occurs in traces in air, and more abundantly in natural gas deposits. It is used as a lifting gas for balloons and airships, and liquid helium (boiling point: 4.2 kelvins, −268.9°C) is used as a coolant. Helium is produced in stars as the main product of the thermonuclear fusion of hydrogen, and is the second most abundant element in the universe after hydrogen Example sentencesExamples - Does it contain yet more unknown chemical elements, like helium?
- The atomic elements heavier than hydrogen and helium could not have been produced during the inferno of the Big Bang.
- Even though helium is twice as dense as hydrogen, this is less than one metric ton of gas.
- Because it is chemically inert, helium was not identified on Earth until some time later, in 1895.
- Argon is denser than air, and certainly helium, which means that it has more molecules to retain heat.
- They were the ones who were always crying and throwing fits when they lost their helium balloons.
- During the history of our universe, more helium was made because the process that drives the stars turns hydrogen into helium.
- Other light elements that are commonly proposed for the outer core are silicon, carbon, helium, and nitrogen.
- In composition it resembles a small star, with helium and hydrogen as the main gases.
- Ramsay realized that argon and helium might be members of a hitherto unsuspected new group in the Periodic Table.
- Over the next few years many types of laser were built, some using a mixture of helium and neon, others carbon dioxide or organic dyes.
- In practice air is nowadays never used in deep diving, the nitrogen being replaced by helium, which is far less soluble in fat.
- Today, balloons in Japan are lifted by hot air rather than the more expensive helium or hydrogen.
- Cool the detectors with liquid nitrogen instead of solid hydrogen or liquid helium.
- There he worked with Born on atomic theory, writing a joint paper with him on helium.
- During the last years of his life he worked steadily on the wave mechanics of the hydrogen and helium atom.
- When most of the hydrogen is fused into helium, fusion stops and and gravity again takes over.
- At launch, the balloon is partially inflated with helium and expands as it rises.
- Eventually, there will not be any hydrogen left in the center of the Sun to make helium.
- However, if a proton is added to the hydrogen atom, a new element, helium is created.
OriginLate 19th century: modern Latin, from Greek hēlios 'sun', because its existence was inferred from an emission line in the sun's spectrum. Rhymesberkelium, epithelium, nobelium, Sealyham Definition of helium in US English: heliumnounˈhēlēəmˈhiliəm The chemical element of atomic number 2, an inert gas which is the lightest member of the noble gas series. 氦（符号： He ） Helium occurs in traces in air, and more abundantly in natural gas deposits. It is used as a lifting gas for balloons and airships, and liquid helium (boiling point: 4.2 kelvins, −268.9°C) is used as a coolant. Helium is produced in stars as the main product of the thermonuclear fusion of hydrogen, and is the second most abundant element in the universe after hydrogen Example sentencesExamples - There he worked with Born on atomic theory, writing a joint paper with him on helium.
- At launch, the balloon is partially inflated with helium and expands as it rises.
- During the last years of his life he worked steadily on the wave mechanics of the hydrogen and helium atom.
- When most of the hydrogen is fused into helium, fusion stops and and gravity again takes over.
- In practice air is nowadays never used in deep diving, the nitrogen being replaced by helium, which is far less soluble in fat.
- Eventually, there will not be any hydrogen left in the center of the Sun to make helium.
- Other light elements that are commonly proposed for the outer core are silicon, carbon, helium, and nitrogen.
- Because it is chemically inert, helium was not identified on Earth until some time later, in 1895.
- In composition it resembles a small star, with helium and hydrogen as the main gases.
- Argon is denser than air, and certainly helium, which means that it has more molecules to retain heat.
- Today, balloons in Japan are lifted by hot air rather than the more expensive helium or hydrogen.
- The atomic elements heavier than hydrogen and helium could not have been produced during the inferno of the Big Bang.
- They were the ones who were always crying and throwing fits when they lost their helium balloons.
- Over the next few years many types of laser were built, some using a mixture of helium and neon, others carbon dioxide or organic dyes.
- During the history of our universe, more helium was made because the process that drives the stars turns hydrogen into helium.
- Even though helium is twice as dense as hydrogen, this is less than one metric ton of gas.
- Cool the detectors with liquid nitrogen instead of solid hydrogen or liquid helium.
- Does it contain yet more unknown chemical elements, like helium?
- However, if a proton is added to the hydrogen atom, a new element, helium is created.
- Ramsay realized that argon and helium might be members of a hitherto unsuspected new group in the Periodic Table.
OriginLate 19th century: modern Latin, from Greek hēlios ‘sun’, because its existence was inferred from an emission line in the sun's spectrum. |