X unit

For the software testing tools, see xUnit.

The x unit (symbol xu) is a unit of length approximately equal to 0.1 pm (10 m). It is used to quote the wavelength of X-rays and gamma rays.

Originally defined by the Swedish physicist Manne Siegbahn (1886–1978) in 1925, the x unit could not at that time be measured directly; the definition was instead made in terms of the spacing between planes of the calcite crystals used in the measuring apparatus. One x unit was set at ⁄_3029.04 of the spacing of the (200) planes of calcite at 18 °C.

单词	X unit
释义	X unit 英语百科 X unit For the software testing tools, see xUnit. The x unit (symbol xu) is a unit of length approximately equal to 0.1 pm (10 m). It is used to quote the wavelength of X-rays and gamma rays. Originally defined by the Swedish physicist Manne Siegbahn (1886–1978) in 1925, the x unit could not at that time be measured directly; the definition was instead made in terms of the spacing between planes of the calcite crystals used in the measuring apparatus. One x unit was set at ⁄_3029.04 of the spacing of the (200) planes of calcite at 18 °C.
随便看	ignis fatuus的意思 ignis infernalis的意思 ignis judicium的意思 igniss的意思 Ignis sacer的意思 ignis Sancti Antonii的意思 ignis St.Ignatii的意思 ignitabilities的意思 ignitability的意思 ignitability number的意思 ignitability of primary deck covering的意思 ignitability test of material的意思 ignitable的意思 ignitable dust的意思 ignitable,ignitible的意思 ignitable material的意思 ignitable mixture的意思 ignite的意思 ignite的意思 ignite的意思 Ignited Fomes的意思 ignited residue的意思 ignited soil的意思 ignited whisky的意思 igniter的意思