The Search Engine for Astronomy and Astrophysics covering over 100,000 pages.

Bayer (the aspirin company) hosts a cool interactive Flash webpage with the Periodic Table of the Elements where descriptions of the elements pop up as you move your cursor over each element on the table. The explanations also tell you what each element is commonly used for.

The CSA/NBII Biocomplexity Thesaurus was developed in 2002-2003 through a partnership between the NBII and CSA, a leading bibliographic database provider. The Biocomplexity Thesaurus is a merger of five thesauri: the CSA Aquatic Sciences and Fisheries Thesaurus; the CSA Life Sciences Thesaurus; the CSA Pollution Thesaurus; the CSA Sociological Thesaurus; the CERES/NBII Thesaurus. Merging and reconciliation of the terms in these thesauri was performed by Jessica Milstead, a leading expert in the development of scientific thesauri. The NBII Thesaurus Working Group oversees expansion of the thesaurus and addition or modification of terms.

This free resource was developed by our staff members and contributors and is still very much under construction. Currently, most of our 8300+ terms deal with biochemistry, biotechnology, botany, cell biology and genetics. We also have some terms relating to ecology, limnology, pharmacology, toxicology and medicine. Don't expect to find common or exotic animals here; there are far too many species to cover even a fraction in a resource like this. However, we've included medically- and biotechnologically-relevant organisms such as bacteria, worms, fungi, and some plants.

Chemical Entities of Biological Interest (ChEBI) is a freely available dictionary of molecular entities focused on ‘small’ chemical compounds. The term ‘molecular entity’ refers to any constitutionally or isotopically distinct atom, molecule, ion, ion pair, radical, radical ion, complex, conformer, etc., identifiable as a separately distinguishable entity. The molecular entities in question are either products of nature or synthetic products used to intervene in the processes of living organisms. All data in the database is non-proprietary or is derived from a non-proprietary source. It is thus freely accessible and available to anyone. In addition, each data item is fully traceable and explicitly referenced to the original source.

United States Central Intelligence Agency. About the CIA. CIA careers. Press room. Library and reference. Federal government links. Director of Central Intelligence. Central Intelligence Agency. CIA's Homepage for Kids.

The Current Index to Statistics is a bibliographic index to publications in statistics and related fields. References are drawn from 162 core journals (as of 2003) that are fully indexed, non-core journals from which articles are selected that have statistical content, proceedings and edited books, and other sources. The Current Index to Statistics is a joint venture of the American Statistical Association and the Institute of Mathematical Statistics.

The Information Bridge provides the open source to full-text and bibliographic records of Department of Energy (DOE) research and development reports in physics, chemistry, materials, biology, environmental sciences, energy technologies, engineering, computer and information science, renewable energy, and other topics. The Information Bridge consists of full-text documents produced and made available by the Department of Energy National Laboratories and grantees from 1995 forward. Additional legacy documents are also included as they become available in electronic format.

In a unique collaboration, Nature Publishing Group and Institute of Physics Publishing published the most extensive and comprehensive reference work in astronomy and astrophysics in both print and online formats. First published as a four volume print edition in 2001, the initial Web version went live in 2002, and contained the original print material and was rapidly supplemented with numerous updates and newly commissioned material. Since August 2004 the Encyclopedia is published solely by the Institute of Physics Publishing. This unique resource covers the entire field of astronomy and astrophysics and this online version includes the full text of over 2,750 articles, plus sophisticated search and retrieval functionality, links to the primary literature, and is frequently updated with new material. An active editorial team, headed by the Encyclopedia's editor-in-chief, Paul Murdin, oversees the continual commissioning, reviewing and loading of new and revised content. The Encyclopedia's authority is assured by editorial and advisory boards drawn from the world's foremost astronomers and astrophysicists. This first class resource will be an essential source of information for undergraduates, graduate students, researchers and seasoned professionals, as well as for committed amateurs, librarians and lay people wishing to consult the definitive astronomy and astrophysics reference work.

Welcome to the Energy Citations Database (1948 Present) Web site. The Energy Citations Database (ECD) is designed and developed by the U.S. Department of Energy (DOE) Office of Scientific and Technical Information (OSTI) with the science-attentive citizen in mind. Its creation is consistent with OSTI's objective to provide easier and faster access to the Department's scientific and technical information. Energy Citations is publicly available without charge to users. Agency information: AEC, ERDA, DOE. Energy Citations contains bibliographic records for energy and energy-related scientific and technical information from the Department of Energy (DOE) and its predecessor agencies, the Energy Research & Development Administration (ERDA) and the Atomic Energy Commission (AEC). The Database provides access to DOE publicly available citations from 1948 through the present, with continued growth through regular updates. Energy Citations includes bibliographic records of literature in disciplines of interest to DOE such as chemistry, physics, materials, environmental science, geology, engineering, mathematics, climatology, oceanography, computer science and related disciplines.

Available as a downloadable PDF file, the ETDE Thesaurus contains the valid descriptors assigned to records in the DOE Information Bridge and to ETDE products such as the Energy Science and Technology Database provided by Dialog Corporation.

At this site you will find over 500 databases and Web sites containing information and resources pertaining to science and technology of interest to the Department of Energy, with an emphasis on the physical sciences. Sponsored, developed, and maintained by the Department of Energy's Office of Scientific and Technical Information (OSTI), EnergyFiles combines information, tools, and technologies to facilitate access to and use of scientific resources.

The goal of this handbook is to help scientists and engineers incorporate statistical methods in their work as efficiently as possible. By NIST/SEMATECH.

Developed by the US Environmental Protection Agency (EPA), this online dictionary defines in non-technical language the more commonly used environmental terms appearing in EPA publications, news releases, and other Agency documents available to the general public, students, the media, and Agency employees.

Values given below are from the CODATA 1998 recommended by the National Institute of Standards and Technology of United States (NIST). Values contain the (uncertainty) in the last two decimal places given in brackets. Values that do not have this uncertainty listed are exact.