from
CURTIN...
Product Capsules O s m o m e t e r s . U n i t determines molecular weight of macromolecules. 175
Pick the Vacuum Pump that Fits Your Needs!
O v e n s . Bulletin on unit with 40° t o 200° C . t e m p , range. 52 O x y g e n Meters. Specs, on unit for measuring dissolved oxygen. 129 pH Meters. Bulletin on direct reading unit with 7-inch scale. 110
1397B—TWO-STAGE [Vented Exhaust! 0 1 MICRON 425 LITERS/MINUTE
1398—TWO-STAGE (Vented Exhaust) 0.1 MICRON 1400 LITERS/MINUTE
1400B—TWO-STAGE 0.1 MICRON 2 1 LITERS/MINUTE
I 4 0 4 H — SINGLE-STAGE iWegner Pumpi 20 MICRONS 33 4 LITERS/MINUTE
1403B— SINGLE-STAGE 5 MICRONS 100 LITERS/MINUTE
1405 H—TWO-STAGE 0.05 MICRON 33.4 LITERS/MINUTE
1402B—TWO-STAGE (Vented Exhaust) 0.1 MICRON 140 LITERS/MINUTE
1406H —SINGLE-STAGE 5 MICRONS 33.4 LITERS/MINUTE
1392—TWO-STAGE (Mechanical & Diffusion) 0.001 MICRON 6 0 0 LITERS/MINUTE' (at 0.1 micron)
1410B—SINGLE-STAGE (Wegner Pump) 2 0 MICRONS 2 1 LITERS/MINUTE
pH Meters. Info on complete line of p H m e t e r s a n d electrodes. 87 pH Meters. Bulletin on line operated unit in metal case. 109
;se
Phosphorus P e n t o x i d e . Info on deh y d r a t i n g agent in pellet form. 102
*l?c»l 4000
Photometers. Data and fluorimeter.
W.H. CURTIN&CK
new GC Packing Kits
Polarimeters. Info on full-circle polarimeter a n d dialyzing vessel. 2 0 8
Now, with Curtin GC Packing Kits, you can try a wide variety of column packings for gas chromatography without investing in large quantities of expensive materials. Three new introductory assortments, coated on Curtin CHROMOPAK*, give you a selection of packings for making trial separations with a minimum of investment and waste. Designed specifically to assist you in solving your gas chromatography problems, Curtin's GC Packing Kits include packing materials for use a t low, medium or high column temperatures. Trial packings are furnished in 25gram bottles, a quantity sufficient for preparing the average length column. K i t " A " includes 10 selected packings, 8 of which are primarily for use with low boiling samples; 1 for medium boilers, and 1 for high boilers. K i t " B " includes 12 packings, 7 of which are for medium boiling samples, 2 for low boilers, and 3 for high boilers. K i t " C " consists of 14 packings, 9 of which are primarily for high boiling samples, 2 for low boilers, and 3 for medium boilers. Thus, with only a modest investment, you can perform numerous separations for comparison to determine the Curtin Column Packings most suitable for your work. For complete information on Curtin GC Packing Kits and Curtin Coated Column Packings, write W. H. Curtin & Company, P. O. Box 1546, Houston, Texas 77001. * A tradename of W. H. Curtin & Co.
W.H. CURTIN & CO. APPARATUS
Pipets. Automatic unit h a s micrometer adjustment for accurate settings. 38 Pipets. All markings are permanently fused into pipets. 187
help solve Column Problems
SCIENTIFIC
Polarimeters. Automatic asymmetric carbon atoms.
unit
Polarographs. 1 0 " chart.
unit has 97
Recording
Potassium Sulfate. reagents offered.
167
ANALYTICAL
Info on line of 27
Presses. Bulletin on unit with u p t o 40,000 lbs. pressure. 37 Pressure Controllers. Catalog on allmetal cartesian diver t y p e unit. 96 Programmers. D a t a sheet on dual column unit for gas chromatographs. 171 Pumps. Compact, low flow unit with 1.5 to 900 m l / h r . capacity. 103 Pumps. Catalog on line of 10 v a c u u m p u m p s offered. 113 Pumps. Bulletin on plastic p u m p s for continuous d u t y . 148 Pumps. F o r ion p u m p i n g a n d T i sublimation pumping. 197 Pumps. Info on mechanical and p u m p carts. Radiochemicals. Data carbon-14 compounds.
pumps 19
on 30 new 224
AND CHEMICALS
Circle No. 64 on Readers' Service Card ·
for 10
Pore V o l u m e A p p a r a t u s . Info on new, low-temp, gas adsorption unit. 221
Recorders. Bulletin 250 m m . chart. 166 A
on colorimeter 65
CHEMISTRY
on unit
with 134
P«t N o . 8,337,849
DUO-SEAL VACUUM
PUMPS
are designed to fit almost every application better and at less cost . . . in the laboratory, industry and school. Ten different models to choose f r o m . . . capacities from 21 to 1400 liters per minute . . . ultimate pressures from 2xl0-2mmHgdownto J xl0-*mmHg and better . . . two-stage and singlestage mechanical pumps with vented exhaust, and mechanical and diffusion combination pumps. Over the years, Welch Duo-Seal Pumps have built a world-wide reputation for best p e r f o r m a n c e , greatest reliability and quietest operation. When you use a Duo-Seal Pump, you're using the best!
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For complete specifications ana prices, ask for Duo-Seal Catalog
I SINCE I k 188.0 [
THE WELCH SCIENTIFIC COMPANY foremost manufacturers of scientific equipment
1515 S e d g w i c k S t . , D e p t . 9 1 1 , C h i c a g o 10, I I I . Circle No. 131 on Readers' Service Card