+250°
IN THE LABuse TIME TAPE for best results!
Proven superior by actual use. Here is the toughest,
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durable
pressure-senitive
THE A C I D I M E T E R AK
tape a v a i l a b l e . WRITE O N IT! TYPE O N IT! Acid, affect +250°
water, it!
dirt,
grease
Withstands
heat
don't
temperatures
or
from
able in plain or pre-printed to your specs. other time-saving uses can cut costs and in
It can also be used as a milivoltmeter within the range of 0 - 8 0 0 m V or 6 0 0 - 1 4 0 0 m V . This apparatus is indispensable for every laboratory.
efficiency.
For samples and prices write to — Dept. GSL
-70°
of 0 - 8 and 6 - 1 4 p H with a high accuracy.
to — 7 0 ° ! A variety of colors a v a i l
Numbers, i d e n t i f i c a t i o n , warning a n d many crease
is designed for the determination of p H in solutions within the range
For further information or leaflets about our other new laboratory ap
TIME
PROFESSIONAL TAPE CO., INC. 355 Burlington Ave. Riverside, Ill.
paratus—apply to:
LABELS
Circle No. 138 on Readers' Service Card
KOVO — PRAHA — CZECHOSLOVAKIA Circle No. 44 on Readers' Service Card
c
14
άΐΓί€ζθν=AΡΙΕΖΟN
®
A P I E Z O N = The Finest Oils, Waxes and Greases for High Vacuum Work Preferred by l e a d i n g scientists for high vacuum equipment a n d systems where low pressure proc ess is used a t one or more stages.
propylene 1-C14 malonic acid-U-C 14 bromoacetic acid-1 or 2-C14 acetone-1,3-C14 acetic anhydride-2-C14
• Vacuum c o a t i n g units and vacuum furnaces for degassing of metals • M e t a l l u r g i c a l vacuum distillation of fight metals • lyophilic drying of peni cillin, vitamins and other substances • Preparation of vitamin concentrates • Dehydrated food • Blood serum drying • The electron microscope
W r i t e for 5 t h edition of r a d i o c h e m i c a l c a t a l o g
As exclusive distributor in the United States, w e o f f e r i m m e d i a t e defivery from stock on the complete r a n g e o f A p i e z o n oifs a n d compounds. For details on applications, working characteristics and list prices, write for Bulletin 43-AC. *from the Greek meaning "without
Tracerlab
JAMES 1601 Trapelo Road, Waltham, Mass.
Circle No. 78 on Readers' Service Card 132 A
·
ANALYTICAL CHEMISTRY
prssure"
B912
G . Β I DDL E C O .
Electrical & Scientific Instruments 1 3 1 6 ARCH STREET, PHILADELPHIA Circle No. 108 on Readers' Service Card
7, PA.
