LABORATORY
SERVICE CENTER
4-Aminoantipyrine · Ammonium Purpurate · Bindschedler's Green 2-Bromoethylamine HBr · tert-Butyl Chloride · Cesium Chloride 5-Chlorosalicylaldehyde · 3,5-Dichlorosalicylaldehyde · Esculin Disodium Succinate · Ethyl Crotonate · Fluorescein · Furoic Acid Hofmann's Violet · 3-lndolebutyric Acid · Levulinic Acid · Methyl Acetamide Methyl-tert-Butyl Ether · Methylene Iodide · p-Naphtholbenzein 4-(4-Nitrobenzyl)Pyridine · Oxamide · Potassium & Sodium m-Periodates Rhodanine · Sodium-4-Hydroxybutyrate · Thioacetamide · Veratraldehyde
HELP WANTED ADS ROP display at ROP rates. Rate based on number of insertions within contract year. Cannot be combined for frequency. Unit 1" (25 mm)
Write for our Products List of over 3,000 chemicals Tel: 516-273-0900 · TOLL FREE: 800-645-5566
Telefax: 516-273-0858 · Telex: 497-4275
EASTERN C H E M I C A L A Division of UNITED-GUARDIAN, INC.
P.O. Box 2500 DEPT. AC S M I T H T 0 W N , N.Y. 11787
CALL
1-TI
6-TI
12-Ti
$200
$180
$170
24-Ti
48-Ti
72-Ti
$160
$150
$140
OR WRITE JANE
GATENBY
ANALYTICAL CHEMISTRY 5 0 0 Post R o a d East
Laboratory Service Center (Equipment, Materials, Services, Instruments for Leasing), M a x i m u m space — 4 inches per advertisement. Column width, 2 - 3 / 1 6 " ; t w o c o l u m n width, 4 - 9 / 1 6 " . Artwork a c c e p t e d . No c o m b i nation of directory rates with ROP advertising. Rates based on number of inches used within 12 months f r o m first date of first insertion. Per inch: 1 " — $ 1 7 5 ; 1 2 " — $ 1 7 0 ; 2 4 " — $ 1 6 5 ; 3 6 " — $ 1 6 0 ; 4 8 " — $155. CALL
OR WRITE JANE
P.O. Box 2 3 1 Westport, C T 0 6 8 8 0 203-226-7131 FAX: 2 0 3 - 4 5 4 - 9 9 3 9
GATENBY
ANALYTICAL CHEMISTRY
F R E E DATA, FAST
500 Post Road East P.O. Box 231 Westport, CT 06880 203-226-7131/FAX: 203-454-9939
JOURNAL OF CHEMICAL AND ENGINEERING
To quickly amass data on all of the products you need, consult the Lab Data Service Section on our Analytical Chemistry reader reply card insert.
Get a World of Precise, Accurate Data. Don't miss a single issue. Subscribe to JCED today!
Multidisciplinary in nature and international in scope, Journal of Chemical and Engineering Data features contributions by distinguished scientists from the world over. Their expert reports represent numerical data bases for private technical information systems, particularly in industry, that will broaden your scientific horizons and improve the quality of your work. This quarterly journal publishes precise, accurate data on physical, thermodynamic, and transport properties of welldefined material. It also keeps you informed about the latest international standards on symbols, terminology, and units of measurement for reporting data properly. EDITOR: Kenneth N. Marsh, Texas A&M University 748 A · ANALYTICAL CHEMISTRY, VOL. 63, NO. 14, JULY 15, 1991
Volume 36 (1991) 4 issues per year U.S. Canada & Mexico Europe* All Other Countries*
ACS Members 1 vear 2 years S32 S37 $41 S41
$57 S67 $75 $75
Nonmembers 1 year S234 $239 $243 $243
*Air service included. For m o r e i n f o r m a t i o n or to s u b s c r i b e , contact: American Chemical Society, Marketing Communications Department. 1155 Sixteenth Street N.W., Washington, D.C. 20036
In a hurry? Call Toll Free 1-800-227-5558 (U.S. and Canada) In D.C. and outside the U.S. and Canada: call (202) 872-4363 Fax: (202) 872-4615; Telex: 440159 ACSPUI or 892582 ACSPUBS Cable Address: JEICHEM Member subscription rates are for personal use only. Subscriptions are based on a calendar year. Foreign payment must be made in U.S. currency, by International money order, UNESCO coupons, or U.S. bank draft, or order through your subscription agency. For nonmember rates in Japan, contact Maruzen Co., Ltd. This publication is available on microfilm, microfiche, and the full text is available online through CJO on STN International.