<s>
Thermal	B-Algorithm
ionization	I-Algorithm
,	O
also	O
known	O
as	O
surface	B-Algorithm
ionization	I-Algorithm
or	O
contact	B-Algorithm
ionization	I-Algorithm
,	O
is	O
a	O
physical	O
process	O
whereby	O
the	O
atoms	O
are	O
desorbed	O
from	O
a	O
hot	O
surface	O
,	O
and	O
in	O
the	O
process	O
are	O
ionized	O
.	O
</s>
<s>
Thermal	B-Algorithm
ionization	I-Algorithm
is	O
used	O
to	O
make	O
simple	O
ion	O
sources	O
,	O
for	O
mass	O
spectrometry	O
and	O
for	O
generating	O
ion	O
beams	O
.	O
</s>
<s>
Thermal	B-Algorithm
ionization	I-Algorithm
has	O
seen	O
extensive	O
use	O
in	O
determining	O
atomic	O
weights	O
,	O
in	O
addition	O
to	O
being	O
used	O
in	O
many	O
geological/nuclear	O
applications	O
.	O
</s>
<s>
One	O
application	O
of	O
thermal	B-Algorithm
ionization	I-Algorithm
is	O
thermal	B-Algorithm
ionization	I-Algorithm
mass	O
spectrometry	O
(	O
TIMS	O
)	O
.	O
</s>
<s>
In	O
thermal	B-Algorithm
ionization	I-Algorithm
mass	O
spectrometry	O
,	O
a	O
chemically	O
purified	O
material	O
is	O
placed	O
onto	O
a	O
filament	O
which	O
is	O
then	O
heated	O
to	O
high	O
temperatures	O
to	O
cause	O
some	O
of	O
the	O
material	O
to	O
be	O
ionized	O
as	O
it	O
is	O
thermally	O
desorbed	O
(	O
boiled	O
off	O
)	O
the	O
hot	O
filament	O
.	O
</s>
<s>
The	O
disadvantages	O
of	O
this	O
method	O
stem	O
from	O
the	O
maximum	O
temperature	O
achieved	O
in	O
thermal	B-Algorithm
ionization	I-Algorithm
.	O
</s>
<s>
The	O
hot	O
filament	O
reaches	O
a	O
temperature	O
of	O
less	O
than	O
2500°C	O
,	O
leading	O
to	O
the	O
inability	O
to	O
create	O
atomic	O
ions	O
of	O
species	O
with	O
a	O
high	O
ionization	O
energy	O
,	O
such	O
as	O
osmium	O
and	O
tungsten	B-Application
.	O
</s>
