MAKING THE MOST OUT OF CAS ONLINE
1. DO YOU REALLY NEED AN ONLINE SEARCH?
The most obvious way to save money for your CAS ONLINE
allocation is to find the information you seek in another
way. The Chemistry Library Handbook describes some of the
more important printed reference sources. Online searching
should not be viewed as the best way to get answers to all
questions which chemists have. You may want to talk to a
librarian (Gary Wiggins or Roger Beckman) to discuss
alternative ways of solving your problem. Everything you do
under the CAS ONLINE program costs money, even though we have
a substantial discount. STUDY THE PRICE LIST CAREFULLY!
2. HAVE YOU PREPARED YOUR SEARCH STRATEGY CAREFULLY BEFORE
a. Look for the most appropriate search terms and utilize
the controlled vocabulary terms effectively. You should
use the the Chemical Abstracts Index Guide and may want
to use some of the following which are kept on the
Computer Reference Shelves in our work area.
CA Headings Lists
"General Subject Headings"
"Plant and Animal Headings"
The CA Headings Lists contain all of the terms (except
chemical names) used in the 9th - 11th Collective Index
periods (1972-86). Terms change from one five year CI
period to another. The Index Guide and these lists can
help you find out what terms to use.
Registry Handbook-Common Names
This microfiche set is kept near the microform reader. By
using the set, you can often find the registry number for
a compound if you know a name.
"Standard Abbreviations, Acronyms, Special Characters,
and Symbols in CAS Computer-Readable Files and
This small publication can show you which abbreviations
should be used. For example, not only should you use the
term "analysis", but also ANAL. Effective use of
abbreviations can really help your searching.
3. BEFORE USING CAS ONLINE.
a. There are CBT guides for searching the CA and Reg files.
The STN Mentor Laboratory series may be accessed on the
IBM computers in 006. These simulate many features of
the CAS ONLINE system.
b. Write down your search strategy and the commands needed
to accomplish your search before going online. Think
about the limitations you want to impose (years,
language, document types, etc.) and make sure you know
how to limit your answer sets to just the kind of
information you want. Do not wait to look this up when
you are online. However, if the computer does not accept
the command structure you try, use the HELP command to
find out where you went wrong.
c. Printing out a few references in the SAMPLE format may
help you select better terms if your original strategy
does not seem to be working as well as you expected.
Use of the "DISPLAY SCAN" option can also help.
EVERY UNNECESSARY SECOND YOU SPEND ONLINE WASTES MONEY!
d. If at some point during your search you need to look up
some information to help you, you can use the LOGOFF HOLD
command. This command saves your search strategy for 20
minutes and actually disconnects you from CAS ONLINE.
When you log back on within the 20 minute period, you can
resume your search at the point where you entered LOGOFF
4. WHAT IS THE BEST WAY FOR YOU TO GET A PRINTED COPY OF YOUR
A quick glance at the Price List shows that you are charged
more for the more information you actually print out.
Offline prints cost an additional $0.10 per item at the
a. Printing an answer set while online using the DISPLAY
command is probably all right if the answer set is not
more than 100 items. For any large answer set (more than
twenty answers) in the CA File, you should probably use
DISPLAY TI 1-n
command to be sure that your strategy has worked. You
can then select the answer numbers for which you really
want fuller references.
b. You might want to consider downloading the answer
set and printing it later on your printer. You will
still generate a cost per item which is dependent on the
format chosen, but the connect hour fee may be somewhat
c. You may want to use the offline print option (the PRINT
command). Under the Academic Program, the discount
applies to offline prints as well as to online costs.
Therefore, if you can afford to delay (usually no greater
than one week), this is a viable option for answer sets
larger than 100. Be aware that if you use the PRINT
command while connected through Infogate, the offline
prints are sent to the Chemistry Library.
5. IF YOU ARE DOING A REGISTRY FILE SEARCH:
a. It is possible to start with the structure of a known
compound for which you have a registry number. Just
enter the registry number at the point where you see:
ENTER NAME OR STRUCTURE TO BE RECALLED (NONE):
b. It is possible to start with any of 42 pre-drawn ring
structures, including those for larger rings, common
fused ring systems, coordination compound fragments, and
boron cages. See a librarian for the list of pre-drawn
c. You should always do a sample structure or substructure
search first. It's FREE. Only be doing a sample search
can you be sure that your full file search will run to
d. As well as a structure or substructure search, many terms
can be searched in the Registry file.
These include compound names, molecular
formulas, element counts (may include ranges), and
periodic groups. These terms may be combined with the
results of a structure search.
e. Displaying the answers in a "Display Scan" in the
Registry File is FREE. You do not get the registry
number in this format, but you can see retrieved
f. An easy way to search in the CA File for information on
the preparation of a compound, on general derivatives of
it, or on the preparation of derivatives is to use /P,
/D, or /DP after a set number created in the Registry
File. For example, Search L5/p.
a. You may want to use a DISPLAY COST command at several
points during your search if you feel that you are
burning up a lot of money. Remember when you first get
on to use the commands:
FILE CA Cost=lastname
or: FILE REG Cost=lastname
where lastname is the first eight characters of your
b. If you have used the printed volume or collective
indexes to Chemical Abstracts to identify a number of
abstracts, you can display them online in any format.
The command takes the form: D ACC 102:12345 . If you
have done a manual search on recent Chemical Abstracts
issues which are at the bindery, this is an option the
librarians can do for you during the day on the CARS
password at no charge to you.
c. It is illegal for you to keep downloaded records from
the CAS ONLINE files unless you get a separate license
agreement from the Chemical Abstracts Service. See one
of the librarians for details.
d. If you have any problems with online searching, contact
Gary Wiggins or Roger Beckman in the Chemistry Library