Fluorene-9-BisPhenol
SCIENCE/TECHNOLOGY Epoxy ResinsHeat Resistance Moisture Resistance Thernto-oxidative Stability
SUV database service celebrates 10th year
Acid Color Developer-
Thermal Recording MaterialImproved Image Retention
Phthalocyanine ThermosetsThermal Stability Fire Resistance
PolyarylatesThermal Stability Tensile Strength Chemical Resistance Electrical Properties Headquarters Weyl GmbH Mannheim, Germany hone [49] (621)7654 394 fax 7654 446
In North America Ruetgers-Nease Corporation State College, PA phone [1] (814) 231-9261 fax 238-4235
CIRCLE 3 8 ON READER SERVICE CARD
Smooth
ODeraDQf tew
Introducing the Durex™ metering pumps. When it comes to consistent, high-pressure delivery, Durex metering ^ pumps make everything go smoothly. A new mechanical design gives you steady low-pulseflowfrom 0.05 to 30 mL/min and pressures to 5000 psi. Theflowrate is set directly. No more fussing with micrometers and look-up tables. Expect years of trouble-free use. Durex pumps are built with the highest quality, corrosion-resistant materials and are backed by expert service. And the price won't p i j ruffle your budget. tlCIGX
&
Durex metering pumps.
CALL
They re steady under pressure.
© 1994, Eldex Laboratories, inc.
i-800-969-3533, FAX 1-707-224-0688
CIRCLE 13 ON READER SERVICE CARD
18
MAY 30,1994 C&EN
STN International is 10 years old this month. Having first become operational in May 1984, the on-line system has grown to include such a sizable battery of science and engineering databases that modern chemists likely would find it difficult to function without them. The accent on chemistry was there at the beginning, when the American Chemical Society's Chemical Abstracts Service (CAS) Division in Columbus, Ohio, joined with Fadiinformationzentrum (HZ) Chemie, in Karlsruhe, Germany, to offer the CAS Registry, CA Files, and HZ Physics Briefs in one combined service. Chemical Abstracts itself had started CAS Online in 1980. The two organizations next invited the Japan Information Center of Science & Technology, Tokyo, to add its own databases, thus establishing service centers accessible to users on three continents. STN continues to grow with the frequent addition of new databases from other organizations, called publishers. Publishers each transmit data to one of the service centers, but users can search any database from all three service centers. A search may shift among computers in Columbus, Karlsruhe, or Tokyo without the client being aware of it. All of the publishers independently maintain, improve, and expand their databases and set pricing policies. The service centers independently solicit new databases and supply search assistance and support to users who contact them. The centers sometimes refer users to individual database publishers for detailed information. STN constantly adds new features to speed and expand searches. In 1986, STN began offering the complete text of the Journal of the American Chemical Society, followed later by entire texts of Chemical & Engineering News and of all research journals of ACS, the Royal Society of Chemistry, Elsevier Science Publishing Co., VCH Verlagsgesellschaft, John Wiley & Sons, and the Association of Official Analytical Chemists International. The first numerical database was added in 1987 with the offering of the Design Institute of Physical Property Data (DIPPR) from the American Institute of Chemical Engineers. Today, there are more than 20 numeric files on chemical, physical, and thermodynamic properties of materials. Stephen Stinson
