VACUUM DISTILLATION PUMP
the EDITOR'S column
SINGLE-STAGE CONSTRUCTION
Extra Large Oil Reservoir dilutes vapors, reduces sticking and corrosion of mechanism. Guaranteed Vacuum 20 microns (0.02 mm Hg) Greater Free Air Capacity 33.4 liters/minute
L.T.Hallett, Editor
PARAMAGNETIC
RESONANCE
tech-
niques are being used in a r a t h e r unique w a y a t the N a t i o n a l B u r e a u of Standards—determination of spectra of free radicals in outer space. Detection and study of extraterrestrial spectra other t h a n the wellknown 21-cm. line of hydrogen would contribute t o knowledge of interstellar gas clouds and perhaps of p l a n e t a r y atmospheres. Effective radiotélescope searches for such spectra require a minimum bandwidth of t h e receiver, which in t u r n can be accomplished only if line frequencies t o be detected are known accurately. P a r a m a g n e t i c resonance techniques are being used t o determine frequencies b y which radicals b e lieved t o exist in outer space m a y be detected. Long-lived O H radical measurements have been completed and with modifications in the equipment, the short-lived C H and S H radicals m a y be determined. T h e ground rotational levels of the radicals being studied are split by a Λ-type doubling, with t h e splitting falling in the low micro wave range of frequencies. T h e A-type spectra are of the electric dipole type, having intrinsic inten sities several orders of magnitude larger t h a n the magnetic dipole hyperfine spectra, of which the hydro gen 21-cm. line is a n example. Therefore, concentrations of these hydrides as low as 10"° molecule/ cm. 3 should be detectable, compared to 10~2 hydrogen a t o m / c m . 3 The paramagnetic resonance technique overcomes the insensitivity of conventional microwave spectroscopic techniques a t the fre quencies of t h e molecular transi tions under study. T h e strong magnetic field applied t o the m a terial being studied shifts the low
Pump Revolutions—300 RPM Motor—1/3 HP—1725 RPM Tubing Required—S/8-inch i.d. Over-all Dimensions of Mounted Pump 19MxllMxl5M inches high Belt-tightening Provision Extra Supply of Duo-Seal Oil
PRICE
_
J
NO. 1404H P a t e , l t N ° 1404H. WEGNER PUMP, Motor Driven. For 115 volts, 60 Cycles, A. C. Each $150.00 14041. WEGNER PUMP, Motor Driven. For 230 volts, 60 Cycles, A. C. Each $152.00
2337 49
"
$
1505£
Complete with Motor
1404F. WEGNER PUMP, Motor Driven. For 115 volts, D C . Each $215.00 For attached Belt Guard add $17.50 to prices. 1404. WEGNER PUMP, Unmounted. With pulley, but without motor, belt, or base Each $115.00
THE WELCH SCIENTIFIC COMPANY -ESTABLISHED 18801515 Sedgwick Street, Dept. A-1, Chicago 10, Illinois, U. S. A. Manufacturers of Scientific Instruments and Laboratory Apparatus
NEWTHINLAYER CHROMATOGRAPHY ADSORBENT MYRISTYl ALCOHOL
ADSORBENT:
USE
ANASIL S
CHOLESTEROL PALMITATE
SOLVENT SYSTEM: SKELLYSOLVE Β — 90 PARTS ETHYL ETHER — 1 0 PARTS ACETIC ACID - 1 PART
ANASIL
VIETHYL PALMITATE
DEVELOPING TIME: 20 MINUTES'
TRIPALMITIN
FOR
PALMITIC ACID
Sharper Separations CEPHALIM
Faster Determinations Shorter Drying Cycles
CHOLESTEROL
ORIGIN POINTS "
More Analyses Per Day 'Developing time using conventional TLC silica gels: 40 minutes
ANASIL is a new and completely different TTC adsorbent that provides both rapid analysis and excellent resolution. It has been found superior to commonly-used silica gel preparations for many applications. See chart above. AVAILABLE WITH AND WITHOUT BINDER
ANASIL is furnished in two forms, both containing S1O2: ANASIL Β contains CaSCU binder. It is an excellent general-purpose adsorbent for consistently providing repro ducible TLC plates. ANASIL S contains no binder. It is ideally suited for the analysis of lipid classes — including phospholipids and other complexes where the presence of binder
interferes with normal migration of individ ual components. Both Anasil Β and Anasil S yield thin, adherent, homogeneous films. PRICE: Only S12 per 11/2 lb. bottle of either Anasil Β or S. Quantity discounts o n four bottles and up. Immediate delivery from stock. JUST OFF THE PRESS! NEW CATALOG on today's most complete line of gas chroma tography accessories and supplies—including 58 new specially-synthesized polar phases for advanced GC research. Write for your free copy today.
ANALABS ANALYTICAL ENGINEERING LABORATORIES, INC.
P.O. Box 5215, Hamden 18, Conn., ATwater 8-3400 Circle No. 100 on Readers' Service Card
VOL. 34, NO. 3, MARCH 1962
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