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CHBE Orientation Program. Searching the Literature. Background. A literature search in the first step in any research program Recall 551 exam You need to know What has been done before What techniques have been used Who are the leaders What are the open questions
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CHBE Orientation Program Searching the Literature
Background • A literature search in the first step in any research program • Recall 551 exam • You need to know • What has been done before • What techniques have been used • Who are the leaders • What are the open questions • All of you are now assigned to research groups • No better time than the present to start your literature search • By April you will need to present a seminar on your research topic (requires literature search)
Objective For Today • Discuss basic strategies for literature searches • Details on Scifinder and web of science, Engineering Village
Effective Literature Searching Four key steps • Preparing for the search • What information am I looking for? • How can I formulate the question so search engine can answer it • Doing the search • Choosing the right initial search terms • Choosing the right databases • Updating the search terms when you see the results returned by the databases • Be sure to do cited reference searches • Analyzing the results • What should I learn from the papers? • Reporting the results • Previous literature section of the proposal
Let me get onto Scifinder to Do A Search • http://scifinder.cas.org • Need a login: information is at http://www.library.illinois.edu/chx/sfchanges.html
Search Engines Are Not People • Search engines use algorithms to find information • The cannot understand the scientific content or importance of an article • They can only look for words, phrases, possibly chemical structures • Most search engines are indexed by index terms and author supplied titles, keywords, references and possibly abstracts • You need to formulate your search so the search engine can find it
Examples Of Why Indexing Is Important How can I find this article? Possible search terms • Polyelectrolyte brushes • METAC • Poly 2-(meth acryloyloxy) ethyl trimethyl ammonium chloride • The structure of the polymer Reference found Reference not found
Example: Something Masel Worked On A Few Years Ago • Polyelectrolyte brushes and related structures as catalyst inks (i.e. polymer supports) for fuel cells • What search terms do I use to find previous literature? • Polyelectrolyte brush & fuel cell (no hits) • Polyelectrolyte brush (409 references) • Polyelectrolyte & brush (609 references) • Several mention nanoparticles • Polyelectrolyte & brush & Nanoparticle (50 references – several on target). • Am I done?
At This point I have missed most of the previous literature • Fuel Cell & Nafion – 3986 references • Fuel cell & acrylic acid 932 references • Fuel cell & styrene sulfonate (300 references) • Am I done?
Not done yet!! • Only looked at polyelectrolyte’s • Also need to search other terms • Catalyst inks for fuel cells
Key Conclusions • Start with pretty generic search terms • Refine terms to find what you want • Do this several times with different key words • It is too easy to miss things if you only start with one group of key words • Missing a body of literature guarantees you will not be funded. • It is better to have more references than fewer
I find It Is Important To Prepare For The Search • Make a list of keywords before you start • Make sure you cover everything on your list • People tend to stop when they find the first 20-50 interesting references • Having a list keeps me going so I can find the complete literature.
So Far Only Key Word Searches- Also Need To Do Author Searches • Author searches are much more effective than keyword searches • The search engines do not have to add index terms • I usually find people who are working in an area and then do author searches • I find that I find many more articles this way instead of using key word and structure searches • Can save search with your competitors names so you always get them • This also gives you ideas for key words
Cited Reference Searches Much More Effective Than Key Word Searches Cited reference searches are searches where you find papers who cited a key paper • Indexing cited references can be done automatically since the author has provided the references in a standard format • Search engine does not have to manually add key words • Not dependent on authors choosing the same key words as you • Much quicker and more effective than key word searches
Cited Reference Search • Find Papers By Leaders In An Area • Find Who Cites those papers • Repeat for review articles • Example • Masel’s formic acid fuel cell paper from 2002 • Kenis work on Laminar Flow reactors
Caution Search Engines Miss Things Comparison of SciFinder Scholar and Web of Science Coverage, Whitley, Katherine M. 2002. Analysis of SciFinder Scholar and Web of Science Citation Searches. J Am Soc Info Technol 53(14): 1210-1215. , doi: 10.1002/asi.10192 Duplication analysis, haphazard sample of U.S. academic chemistry researchers. (The table shows results for 2-3 researchers in each of seven chemistry subject areas; the chart below shows just the totals / averages of the seven subjects.)
Scifinder Scholar • Software from Chem Abstracts • UIUC has a site license • Available on the web • http://scifinder.cas.org • Need a login: information is at http://www.library.illinois.edu/chx/sfchanges.html • Need Illinois domain to use • Need VPN if you want to use this from home • VPN downloadable from http://www.cites.uiuc.edu/vpn/index.html
Key Limitations Of Scifinder • Librarians/linguists not chemists do most indexing • Indexing by CAS number not IUPAC structure • Misses articles not published in chemical journals • e.g. IEEE sensors, MRI imaging • Patent coverage spotty • Logical searches particularly weak • You can and two searches on your computer, but only after you download them 100 references at a time • Weird license limitations
License Limitations For Scifinder • Download at most 100 references at a time, 5000 per session • Requires downloads to do logical (And/or) searching • Allowed to only keep 5000 search results at a time in format written by scifinder • No limitation on references imported to endnote or refworks provided search results deleted from your computer • No commercial/consulting use
Examples Scifinder • http://scifinder.cas.org Web Of Science • http://www.library.uiuc.edu/orr/get.php?instid=258127 Engineering Village • http://www.engineeringvillage.com Scopus • http://www.scopus.com Google
Summary • You need a good literature review for orals • Start now • Random use of search engines usually misses key literature so you need a strategy • Plan and then execute • Be sure to do author and cited reference searches • Strategy should consider indexing – requires a different strategy for • Papers in the last 6 months (usually only cited reference searches) • Papers since 2001 – usually found in common search engines by many key words, structures • Papers before 2001 – only key word and cited reference searches effective. • Cited reference searches are particularly effective since the indexing terms are provided by the authors in a consistent way