Several fonts have barely noticable differences between Capital I, lower case l 
and numeric 1. particularly in small font sizes.  Is there an argument for 
being 
emotionally attached to "l"?  I know decimal vs comma, and meter vs metre will 
never get resolved, but I had high hopes for l vs L and dalton vs uamu.




________________________________
From: Martin Vlietstra <vliets...@btinternet.com>
To: U.S. Metric Association <usma@colostate.edu>
Sent: Tue, April 9, 2013 9:41:14 AM
Subject: [USMA:52656] Re: Daltons


The Dalton/amu argument will probably surface after the 2014 CGPM congress 
(where the redefinition of the kilogram, ampere, kelvin and mole will be 
discussed – see http://en.wikipedia.org/wiki/New_SI_definitions  ).   Any 
dropping of the “l” in favour of “L” for the litre is likely to meet resistance 
in Europe – it is only the Anglo-Saxons who have a problem with “l” to 
represent 
the litre and that is because we do not have a stroke on the number “1” when we 
handwrite it.
 
From:owner-u...@colostate.edu [mailto:owner-u...@colostate.edu] On Behalf Of 
John M. Steele
Sent: 09 April 2013 10:35
To: U.S. Metric Association
Cc: U.S. Metric Association
Subject: [USMA:52655] Re: Daltons
 
I don't believe the dalton replaced the unified atomic mass unit (symbol "u").  
The SI Brochure describes them as alternate names (and symbols) for the same 
unit.  Actually I only looked in NIST SP330, where the dalton is listed first.  
That may signify it is preferred but the text does NOT explicitly say so.  The 
situation is analogous to two symbols for the liter. "Unified atomic mass unit" 
is quite a mouthful.  I always use dalton and I don't see why the unified 
atomic 
mass unit can't be deprecated in favor of the dalton.  Of course, I don't see 
why "l" can't be deprecated in favor of "L", either.
 
The unit is important in chemistry as the amu is approximately the number of 
proton and neutrons in the nucleus, and the connection between the gram and 
mole 
(although the BIPM manages to define the mole without ever mentioning it or 
Avogadro's number).  Binding energy and the averaging over naturally occuring 
isotopes gives rise to non-integer values.
 

________________________________

From:Paul Trusten <trus...@grandecom.net>
To: U.S. Metric Association <usma@colostate.edu>
Cc: U.S. Metric Association <usma@colostate.edu>
Sent: Tue, April 9, 2013 12:35:05 AM
Subject: [USMA:52652] Re: Daltons

It takes a long time to achieve de facto deprecation of a unit. If the amu was 
replaced by the dalton in 1961, no one reached the authors of my first science 
textbooks or teachers with the news (1965). In fact, I never heard of the 
dalton 
until the mid-seventies,  so we shall probably continue struggling with that 
old 
name for Celsius for a while to come, too, even 65 years after its deprecation. 


Paul Trusten, Reg. Pharmacist
Vice President
U.S. Metric Association, Inc.
Midland, Texas USA
www.metric.org 
+1(432)528-7724
trus...@grandecom.net


On Apr 8, 2013, at 20:29, Michael Payne <metricmik...@gmail.com> wrote:

> Interesting Unit at http://en.wikipedia.org/wiki/Insulin-like_growth_factor_1 
> 
> forth paragraph down:
> 
> IGF-1 consists of 70 amino acids in a single chain with three intramolecular 
>disulfide bridges. IGF-1 has a molecular weight of 7,649 daltons. 
>
> 
> There is another page on Daltons 
>http://en.wikipedia.org/wiki/Dalton_%28unit%29  A unit accepted for use with 
>SI, 
>seems with the prefixes we have, some sub unit of a gram would have been 
>equally 
>good. Or is this something like the Astronomical unit on the other end of the 
>scale?
> 
> Michael Payne
> 
> 

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