假定值表示小时:

In [86]: import datetime as DT
In [87]: data = [16.       ,   16.00000381,  16.00000572,  16.00000954,
16.00001144,  16.00001335,  16.00001717,  16.00001907,
16.00002098,  16.0000248 ,  16.00002861,  16.00003052,
16.00003433,  16.00003624,  16.00003815,  16.00004196,
16.00004387,  16.00004768,  16.00004959,  16.00005341]
   ....:    ....:    ....:    ....: 
In [88]: map(str, [DT.timedelta(seconds=x*60*60.0) for x in data])
Out[88]: 
['16:00:00',
 '16:00:00.013716',
 '16:00:00.020592',
 '16:00:00.034344',...
 '16:00:00.157932',
 '16:00:00.171648',
 '16:00:00.178524',
 '16:00:00.192276']