Convert from tan [China] to dalton

Unit Definition (tan [China])
The tan is a traditional Chinese weight unit, now spelled dan in English transliteration. During the European colonial era the tan was equal to 100 cattys or 1600 taels. This is equivalent to 133.333 pounds, making the tan comparable to the European quintal as a commercial weight unit. In modern China the tan, or rather the dan, is equal to 100 jin, which is exactly 50 kilograms (110.231 pounds).

Unit Definition (dalton)
The dalton is an alternate name for the unified atomic mass unit (u or amu). The dalton is often used in microbiology and biochemistry to state the masses of large organic molecules; these measurements are typically in kilodaltons (kDa). It seems necessary to have such a unit, since "kilo-amu" would be such a clumsy name. The SI accepts the dalton as an alternate name for the unified atomic mass unit and specifies Da as its proper symbol. The unit honors the English chemist John Dalton (1766-1844), who proposed the atomic theory of matter in 1803.