Stanford University Libraries

Chemical Literature (Chem 184/284)
University of California at Santa Barbara

Lecture 17: Chemistry Resources on the Internet

What is the Internet…really?

  • The Internet is a network of networks; a linkage of computer systems around the world using common protocols to facilitate communication and dissemination of information.
  • The Internet grew out of previous networks designed for military and academic users (UCSB was involved early). Eventually, the Internet became the world’s data communication highway for all sorts of users.
  • Now, the maintenance of the Internet backbone has been passed to commercial firms, and some academic and government users are developing new-generation systems for their own use.

Buzzwords you should know…

  • Telnet: A system that allows you to logon to a remote computer from your own system; for example, remote logon to MELVYL uses the telnet command.
  • FTP: Stands for “file transfer protocol”, this allows sending and receiving of files from remote computers. Downloading software from a manufacturer’s site is an ftp process.
  • Archie: Software designed to allow searching for archives of ftp-able files.
  • Gopher: Software designed at the U. of Minnesota to allow menu access to Internet resources. The first UCSB Library “InfoSurf” was a gopher system.
  • Veronica: Software designed to index resources in “gopherspace”. Both Veronica and gophers in general are becoming obsolete thanks to…

World Wide Web: the hottest part of the Internet

  • The World Wide Web is based on a protocol designed at the CERN laboratories in Switzerland. It allows for hypertext linkages among documents on the Internet and for transfer of text, binary files, graphics, audio, video, etc.
  • Links are created using HTML: Hypertext Markup Language.

HTML: What it does…

  • HTML is an outgrowth of SGML (Standard Generalized Markup Language), a markup system developed for publishing.
  • HTML lets the author label the content of the document so that it can be manipulated by the viewer’s software.
  • In particular, it lets the author embed links to other documents on the Internet.

Web Browsers

  • To use the Web, you need a class of software called a Web browser.
  • Early Web browsers were text based (e.g. Lynx). They could handled hyperlinks among documents, but the documents could only be plain text files.
  • Mosaic, developed at the National Center for Supercomputing Applications at the University of Illinois had two new important features which tremendously accelerated the growth of the World Wide Web:
    • It could handle graphics and other files.
    • It was distributed free of charge.
  • There are now a wide variety of web browsers available. The two most popular are Netscape Navigator or Communicator and Microsoft Internet Explorer.
  • Both come in a variety of forms for a variety of platforms (Windows, Mac, Unix, etc.)
  • Modern Internet browsers will allow to not only to display text files with hyperlinks (.htm or .html) but will handle a variety of graphic file (.gif, .jpg). Other types of files (audio, video, special chemical files) may require helper applications which are separate programs which the browser can open to handle other filetypes, or plug-ins, which operate “transparently” within the browser itself.

Locating Resources on the Internet

  • Like print resources on the library shelves, Internet resources can be located either through classification and data collections or through indexes to the available files.
  • As with other data collections and indexes, quality and usefulness can vary widely depending on your needs.

Data Collections: UCSB’s InfoSurf (http://www.library.ucsb.edu/)

  • The UCSB Library’s web site, InfoSurf, provides links to a wide variety of tools and subject resources.
  • Librarian subject specialists have selected and organized the links for easy browsing.
  • In many cases, the resource links are annotated to help you evaluate them.
  • InfoSurf Chemistry at http://www.library.ucsb.edu/subj/chemistr.html : So far, most links are to useful sites at remote locations. As time goes on, more pages developed at the Library will make original content available.
  • Table of contents at top lets you jump directly to a desired section.
  • “Super Sites” links to other noteworthy data collections.

Web Indexes

  • Numerous web searching tools have been made available. Most are free to use (advertiser-supported); some require subscription.
  • InfoSurf has links to indexing tools. Internet Search Tools at http://www.library.ucsb.edu/tools.html
  • Netscape and other browsers often provide a collection of links to indexes (e.g. “Net Search” button.)
  • Be aware of different approaches:
    • Some search the titles and/or headers and/or full text of items: InfoSeek, Lycos, Webcrawler, Alta Vista, etc.
    • Some use hierarchical subject collections: WWW Virtual Library, EINet Galaxy
    • Some have searchable subject collections: Yahoo
    • Some evaluate their sources: Infomine, Magellan
    • Some of the above now combine different approaches to searching, or link to one another to allow the user greater flexibility.
    • Meta-search engines (Savvy Search) search multiple search engines at once.
  • If you have a very specific term, search engines can be quicker…if they find it at all. But common words, or words which have multiple meanings may lead to large numbers of false hits, burying the items you wish to find.
  • If you have a general term, hierarchical systems may be better in avoiding unrelated material. Hierarchical systems may also find related material of interest.
  • Note that even system which are superficially similar may have different search algorithms and so give different results.

Types of information on the Web

  • Publishers & societies
    Information for authors, members
    Example: American Chemical Society at http://www.acs.org/.
  • Academic institutions
    Faculty, contact information
    Example: UCSB Chemistry Dept. at http://www.chem.ucsb.edu
  • Government-produced information
    Lots of NASA data, Dept. of Commerce, US patent info. Some is on US govt. servers, but some is on other sites maintained by academic institutions or even private companies.
    Examples: NIST Chemistry Webbook at http://webbook.nist.gov
    IBM Patent Server at http://www.patents.ibm.com/ibm.html
    Data tends to be “plain vanilla”; sites which add value to government data tend to charge for their services, such as Chemical Patents Plus at http://casweb.cas.org/chempatplus/ which adds CA chemical indexing to the patent records for US chemical patents.
  • Corporate pages
    • Product catalogs & advertising
    • Contact info; sometimes job listings
    • Almost every major company has some sort of “presence” on the Web nowadays, but the quality of Web site vary dramatically.
  • Electronic journals
    • Electronic journals on the web are rarely free, except as part of some trial offer.
    • Electronic versions of print journals are becoming more and more common. Features and pricing vary widely, as do the degree of added value in the electronic form. Some offer quicker access to articles, some offer supplementary material. See the ACS Publications at http://pubs.acs.org/ for an example.
    • “All-electronic” journals are beginning to spring up. A good example is Internet Journal of Chemistry at http://www.ijc.com. IJC attempts to redesign the classic journal format to fit the Web medium.
    • See ChemConnect’s List of Chemistry Journals Online at http://www.chemconnect.com/library/journals.shtml for a reasonably current list of what’s available on the Web.
  • Downloadable software (some free!)
    • Many software providers use the Web to distribute their software; one notable example is Netscape.
    • Chemistry software manufacturers have also gotten into the act. Molecular Design, Ltd. at http://www.mdli.com/ makes available the Chime software for interactive chemical structures on the Web, for example.
    • Note that free software on the Web is often a beta release version of the software — in exchange for free software, you get to help find bugs in the product!
  • Web interfaces to standard databases
    • Many commercial database providers are now providing Web access to their products. These interfaces are usually menu-driven and aimed more at end-users than professional searchers.
    • Most require subscriptions (Cambridge, SilverPlatter) or an account with the database provider (STNEasy, Dialog Web). As electronic commerce on the Web becomes more widely available, users may be able to do individual searches on such sites by charging them to a credit card number or using electronic cash.
    • A few, mainly government databases, are free. PubMed at http://www.ncbi.nlm.nih.gov/PubMed/, the free public version of Medline, is a good example of this type of service.

This page created by Chuck Huber (huber@library.ucsb.edu).

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