Dear Joshi and Tim

may I ask you what this is useful for???

1TU is defined as a ratio of tritium to hydrogen atoms of 1e-18,
so by definition 1Mol of Water with 1TU contains 3e-18g of Tritium.
Or in one liter with 1 TU there is 3e-18 *1000/18=1.7e-16g Tritium.
If you really want to know that.

But since you are talking of contaminant transport, why the hell do you want
to swich units to g/l???
The Unit TU is linear to mixing of different water masses, and as far as I
know the differential equations of contaminant transport, they work well
with TU...

So what is this good for? Use TU in your transport model!


Dr. Axel Suckow
Institut für Geowissenschaftliche
Gemeinschaftsaufgaben (GGA);
Institute for Joint Geoscientific Research (GGA);
Geochronology and Isotope Hydrology (S3);
Stilleweg 2;
30655 Hannover;
Phone: +49 511 6432527;
Fax:   +49 511 6433665;
e-mail: [log in to unmask] <mailto:[log in to unmask]>

-----Ursprüngliche Nachricht-----
Von: Joshi, Bhaskar [mailto:[log in to unmask]]
Gesendet am: Mittwoch, 31. Januar 2001 18:14
An: [log in to unmask]
Betreff: Re: errata

Hello Tim:

I shall be very grateful if you can review the following calculation for me.
It is based on the input received from you

3.2 pCi/L =1 TU = 2.09E7 atoms/L        (Am I right here?? How do you get
the atoms/L)

Now 3g Tritium = 6.023E23 atoms

So 1 atom of Tritium = (3/6.023E23) g

So 1TU = (2.09E7*3/6.023E23) g/L = 1.04E-16 g/L

Now 1 TU = 0.118 Bq/ L (from Clark & Fritz pp. 175)

so 1 TU = 1.04E-16 g/L = 0.118 Bq/L

Can we then say that

1.04E-16 g of Tritium = 0.118 Bq                ????

Even though Bq is a frequency unit (dps)it appears that it can be
equivalenced to mass of tritium.
 I have to convert TU into a mass unit for a contaminant transport
simulation and this is the way I found

But is this valid??

I shall be very grateful for your help


Bhaskar Joshi


-----Original Message-----
From: Timothy P. Rose [mailto:[log in to unmask]]
Sent: Tuesday, January 30, 2001 10:21 AM
To: [log in to unmask]
Subject: [ISOGEOCHEM] errata

You are correct that 1 TU = 3.2 pCi/L, not the other way around.  Sorry for
the misinformation.  I'll go a little slower before I hit the reply button
next time.
- Tim

Timothy P. Rose
Analytical and Nuclear Chemistry Division, L-231
Lawrence Livermore National Laboratory
Livermore, CA  94550
Phone: 925-422-6611
Fax: 925-422-3160
email: [log in to unmask]