SN4 ""

No	Pattern	Freq
1	at [n mass] [prep]	1524
2	at [n mass] for	383
3	at [n mass] per	275
4	at [n mass] in	206
5	at [n mass] on	135
6	at [n mass] to	104
7	at 37°c [prep]	90
8	at [n mass] against	73
9	at [n mass] with	70
10	at [n mass] of	51
11	at 4°c [prep]	42
12	at [n mass] after	34
13	at [n mass] from	30
14	at people [prep]	25
15	at [n mass] by	24
16	at [n mass] plus	19
17	at [n mass] at	19
18	at 36p [prep]	17
19	at 65°c [prep]	13
20	at [n mass] as	12
21	at [n mass] including	12
22	at 60°c [prep]	10
23	at 30°c [prep]	9
24	at headquarters [prep]	9
25	at £1 [prep]	9
26	at 55°c [prep]	9
27	at £5 [prep]	9
28	at £2 [prep]	9
29	at £6 [prep]	8
30	at [n mass] over	8