Guinea Pig Hepatoma Cell
Γ ThetASTttowl^ for your chromatographic needs... residue free solvents Micrograph courtesy of Dr Harry Ohanian, National Cancer Institute, Bethesda, MD
DISTILLED-IN GLASS
This 4000x micrograph of a Line 1 guinea pig hepatoma cell (induced by diethylnitrosamine feeding) shows detail normally masked by the heavy gold coating necessary to prevent charge effect interference in conventional SEM's. Coates & Welter's brighter field emission electron gun permits high-speed scanning . . . minimizing charge effect to allow micrography of uncoated (or lightly coated) specimens.
from BURDICK & JACKSON LABORATORIES Ask for Data Sheet BJ-25 Distilled-in-Glass Solvents BJ-21 Liquid Scintillation Counting
COATES s WELTER
BURDICK & JACKSON LABORATORIES, INC.
Advancing lite science research through electron microscopy. 777 N. Pastoria Avenue, Sunnyvale, CA 94086, USA 408-732-8200 A subsidiary of
American Optical Corporation
MUSKEGON, MICHIGAN 49442
(616) 726-3171
CIRCLE 40 ON READER SERVICE CARD CIRCLE 36 ON READER SERVICE CARD
PARR®
BOMBS
NÉW
Pharmacia Peristaltic Pump P-3 A compact pump electronically controlled for constant liquid flows in chromatography and gradient formation
For O x y g e n C o m b u s t i o n For A c i d D i g e s t i o n For A l k a l i n e F u s i o n
You can •
Standard procedures for sulfur and halogens depend upon Parr oxygen or peroxide combustion bombs for oxidizing solid or liquid samples rapidly with complete recovery of all combustion products; while Parr digestion and fusion bombs give the analyst several effective systems for dissolving silicates, ores and other difficult materials in strong acids or alkalis without losing trace constituents. For details, write or phone: Parr Instrument Company, Moline, Illinois 61265. 309/762-7716 CIRCLE 179 ON READER SERVICE CARD
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obtain three different flow rates at the same time through the three individually tensioned pumping channels change tubes in seconds with the snap-in cassette forget about pulsation thanks to the large driven rollers rely on a constant motor speed, electronically compensated for load and temperature use any flow rate between 0.6 and 400 ml/h per channel with the same gear box reverse the flow instantly push for maximum flow and clear pump lines rapidly For free descriptive literature, write or call: Pharmacia Fine Chemicals Inc. 800 Centennial Avenue Piscataway, New Jersey 08854 Phone (201) 469-1222
Pharmacia Fine Chemicals
CIRCLE 173 ON READER SERVICE CARD ANALYTICAL CHEMISTRY, VOL. 47, NO. 14, DECEMBER 1975 ·
1301 A
