1. Searching Chemical Abstracts - STN
Bret A. Heim
Thomas Byrne Memorial Library

2. Introduction
The CAS program

3. Topics to Be Covered
Specific techniques and strategies for efficient searching in Chemical Abstracts databases
Forming effective search arguments

4. Record Structure
Structured records facilitate precise retrieval of information

5. Field Name “Switches” Search Titles /TI =>s titanium/TI
Search the Basic Index /BI Searches single words from Titles /TI Index terms /IT Supplemental terms /ST Abstracts /AB CAS registry numbers /RN =>s xenon/BI
Search Abstracts /AB s xenon/AB
Search Chemical Name /CN s 1-bromo-1-fluoro-2-butanone/CN
Search Molecular Formula /MF s C14H18N4O3/MF

6. Basic Search Commands
The Search Command s or search At the => prompt type s or search followed by your search argument =>s gas chromatography =>search ibuprofen
The Expand Command e or expand Best used to browse terms =>e fentanyl/CN =>expand Doring/AU Then use the search command =>s e1-e OR =>search e1 or e2

7. Displaying Results
The Browse Command bro use browse to determine whether or not your search is returning the information you need order of elements [display] [browse command] [List #] =>d bro l3 indicate which record number you wish to view :5 end browse and return to search :end
The Display Command d order of elements [display] [List #] [output format] [record numbers] =>d l3 bib displays numbers 1-10 of result list #3 in bibliographic format

8. Special Features
Truncation ? or ! Right , left-hand and internal truncation are available
Right Hand Truncation =>s citronel? retrieves citronellal, citronellene, citronellic acid, citronellol use also for singulars, plurals, etc.
Left Hand Truncation =>s ?benzene retrieves bromobenzene, chlorobenzene, fluorobenzene, nitrobenzene, etc.
Internal Truncation =>s fluor!metric retrieves fluorometric, fluorimetric

9. More Special Features
Proximity Use for “nearness” and word order =>s genetic engineering (adjacent, specified order) =>s genetic(A)engineering (adjacent, either order) =>s genetic?(5W)engineer? (within 5 words, specified order) Question Why use truncation in the above example? =>s genetic?(5A)engineer? (within 5 words, either order)
Language /LA Use to limit items in a List # to a particular language =>s l5 and english/LA

10. Still More Special Features
Publication Year PY =>s palytoxin and PY>1978 =>s palytoxin and PY<1978 =>s palytoxin and PY =>s palytoxin and PY=<1978
Document Types /DT You may wish to restrict your results to a particular type of publication =>s opiate receptors and journal/DT (retrieves journal articles) =>s ibuprofen and patent/DT (retrieves patents)

11. Forming Search Strategies
Write a single search argument to find journal articles in English published after 1992 on oxidation-resistant coatings used for carbon-carbon composites in a high-temperature atmospheric environment

12. Analyze the Components
Terms
oxidation-resistant coatings Other terms? Use truncation? Proximity and word order? Omit the hyphen?
carbon-carbon composites Use truncation? What about the hyphen?
high-temperature Synonyms for high temperature? Omit hyphen? Use truncation?
atmospheric enviroment Is the term “environment” necessary? Use truncation?
Other Restrictions Document Type /DT Language /LA Publication Year /PY

13. Putting It All Together
[first component] and
[second component] and
[third component] and
[fourth component] and
journal/DT and
english/LA and
PY>1992

14. Going Online CAS program is available only after 5p.m.
Arrange appointment with Bret Heim
Presearch exercises must be completed or you will not be allowed to search
Bring a 3.5” floppy disc to capture your session
Connecting to CAS from STN Telnet session
Login and Password
Time Zone Code
Select a File to Search (LCA and eventually CA)
Perform Search, then Logoff

15. Questions