A manual for writers of research papers, theses, and dissertations, 7th edition - Kate L. Turabian 2007

Units of measure
Abbreviations
Part III. Style 20 spelling

In the humanities and social sciences, spell out the names of units of measure such as dimensions, distances, volumes, weights, degrees, and so on. Spell out the numbers or use numerals according to the general rule you are following (see 23.1.1).

five miles

150 kilograms

14.5 meters

In the sciences, use standard abbreviations for units of measure when the amount is given in numerals. (You may use abbreviations in other disciplines, depending on your local guidelines.) Leave a space between the numeral and the unit, except where convention dictates otherwise (36°; 512K), and note that abbreviations are the same in singular and plural. Spell out units of measure when they are not preceded by a number or when the number is spelled out (as at the beginning of a sentence; see 23.1.1).

We injected 10 μL of virus near the implants.

Results are given in microliters.

Twelve microliters of virus was considered a safe amount.

For a list of abbreviations including common units of measure, see 15.55 of the Chicago Manual of Style, 15th edition (2003).