Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
Figure 28. Ampoules containing 7-dehydrocholesterol in ethanol were exposed for 1 h between 11:30 a.m. and 12:30 p.m. at 27° North in India at various altitudes. The conversion of 7-dehydrocholesterol to previtamin D3 and its photoproducts was determined by HPLC. Reproduced with permission from.46
