second
秒 | The second, symbol s, is the SI unit of time. It is defined by taking the fixed numerical value of the caesium frequency ΔνCs the unperturbed ground-state hyperfine transition frequency of the caesium 133 atom, to be 9 192 631 770 when expressed in the unit Hz, which is equal to s-1.
国际单位制中的时间单位,符号s。当铯频率Δν(Cs),也就是铯-133原子不受干扰的基态超精细跃迁频率以单位Hz即s-1表示时,将其固定数值取为9 192 631 770来定义秒。 | 1s=9 192 631 770/Δν(Cs) |
metre
米 | The metre, symbol m, is the SI unit of length. It is defined by taking the fixed numerical value of the speed of light in vacuum c to be 299 792 458 when expressed in the unit m/s, where the second is defined in terms of ΔνCs.
国际单位制中的长度单位,符号m。当真空中光速c以单位m·s-1表示时,将其固定数值取为299 792 458来定义米,其中秒用Δν(Cs)定义。 | 1m=(c/299 792 458)s
=30.663 318…c/Δν(Cs) |
kilogram
千克 | The kilogram, symbol kg, is the SI unit of mass. It is defined by taking the fixed numerical value of the Planck constant h to be 6.626 070 15 × 10-34 when expressed in the unit J s, which is equal to kg m2 s-1, where the metre and the second are defined in terms of c and ΔνCs.
国际单位制中的质量单位,符号kg。当普朗克常数h以单位J·s即kg·m2·s-1表示时,将其固定数值取为6.626 070 15×10-34来定义千克,其中米和秒用c和Δν(Cs)定义。 | 1kg=(h/6.626 070 15×10-34) m-2·s=1.475 521…×1040hΔν(Cs)/c |
ampere
安培 | The ampere, symbol A, is the SI unit of electric current. It is defined by taking the fixed numerical value of the elementary charge e to be 1.602 176 634 ×10-19 when expressed in the unit C, which is equal to A s, where the second is defined in terms of ΔνCs.
国际单位制中的电流单位,符号A。当基本电荷e以单位C即A·s表示时,将其固定数值取为1.602 176 634×10-19来定义安培,其中秒用Δν(Cs)定义。 | 1A=e/(1.602 176 634×10-19) s-1=6.789 686…×108Δν(Cs) e |
kelvin
开尔文 | The kelvin, symbol K, is the SI unit of thermodynamic temperature. It is defined by taking the fixed numerical value of the Boltzmann constant k to be 1.380 649 ×10-23 when expressed in the unit J K-1, which is equal to kg m2 s-2 K-1, where the kilogram, metre and second are defined in terms of h, c and ΔνCs.
国际单位制中的热力学温度单位,符号K。当玻耳兹曼常数k以单位J·K-1即kg·m2·s-2·K-1表示时,将其固定数值取为1.380 649×10-23来定义开尔文,其中千克、米和秒用h、c和Δν(Cs)定义。 | 1K = (1.380 649 ×
10-23/k) kg·m2·s-2
=2.266 665…Δν(Cs)h /k |
mole
摩尔 | The mole, symbol mol, is the SI unit of amount of substance. One mole contains exactly 6.022 140 76 × 1023 elementary entities. This number is the fixed numerical value of the Avogadro constant, NA, when expressed in the unit mol-1 and is called the Avogadro number.
The amount of substance, symbol n, of a system is a measure of the number of specified elementary entities. An elementary entity may be an atom, a molecule, an ion, an electron, any other particle or specified group of particles.
国际单位制中的物质的量的单位,符号mol。1摩尔精确包含6.022 140 76×1023个基本单元。该数称为阿伏加德罗数,为以单位mol-1表示的阿伏加德罗常数NA的固定数值。
一个系统的物质的量,符号n,是该系统包含的特定基本单元数的量度。基本单元可以是原子、分子、离子、电子、其他任意粒子或粒子的特定组合。 | 1mol=6.022 140 76×
1023/NA |
candela
坎德拉 | The candela, symbol cd, is the SI unit of luminous intensity in a given direction. It is defined by taking the fixed numerical value of the luminous efficacy of monochromatic radiation of frequency 540 × 1012 Hz, Kcd, to be 683 when expressed in the unit lm W-1, which is equal to cd sr W-1, or cd sr kg-1 m-2 s3, where the kilogram, metre and second are defined in terms of h, c and ΔνCs.
国际单位制中的沿指定方向发光强度单位,符号cd。当频率为540×1012 Hz的单色辐射的光视效能Kcd以单位lm·W-1即cd·sr·W-1或cd·sr·kg-1 ·m-2 ·s3表示时,将其固定数值取为683来定义坎德拉,其中千克、米、秒分别用h、c 和Δν(Cs)定义。 | 1cd=(Kcd/683)kg·m2·
s-3·sr-1
= 2.614 830…×1010
Δν(Cs)2h Kcd |
