the EDITOR'S column
WELCH @ © VACUUM PUMPS HIGH QUALITY HIGH CAPACITY
L.T. H a l l e t t , E d i t o r
NO
¥ Ν T H E LABORATORY OF T H E M O N T H
article on Shell I n t e r n a t i o n a l R e search's new fundamental research laboratory a t Birlinghoven Castle in West G e r m a n y which appeared in the J u l y 1964 issue of ANALYTICAL C H E M I S T R Y (page 93 A) it was
PAT. NO. 2,337,849
HIGH V A C U U M
re
ported t h a t Shell had developed an a u t o m a t i c instrument for the deter mination of carbon, hydrogen, and nitrogen. Because of the wide spread interest in this development, Shell I n t e r n a t i o n a l Research has supplied us with the following a d ditional information: T h e process of the explosion-like combustion in helium with only 2 - 3 % oxygen as well as the separa tion and q u a n t i t a t i v e determination of the combustion gases were devel oped by W. Walisch [Chem. Ber. 94, 2314 (1961)]. Shell I n t e r n a tional Research has subsequently further automatized this method, so t h a t the percentages of carbon, h y drogen, and nitrogen are printed out within 8 minutes. T h e only manipulations to be carried out are :
INSTALLATION
No need to bolt down the base of the Welch "Duo-Seal" No. 1402B. Like all Welch Vacuum Pumps, just place it on a firm, flat surface and plug it in. The pump is so quiet and vibration-free that it STAYS PUT. Gliech.
• L o w ultimate pressure — 1 Χ 1 0 - 4 mm H g (torr)
SEND FOR THE NEW CONDENSED "DUOSEAL" CATALOG TODAY!
• High pumping speed — 140 liters/minute • Vented exhaust—no need for oil filters or separators
it contains photos d e scriptions, performance curves, dimensions and prices of all pumps.
• Compact, rugged design — 1 9 - 5 A " X 11-7's* X 1 5 - V 2 " high • A i r - c o o l e d . . . l o w maintenance • Long, trouble-free life
THE WELCH SCIENTIFIC COMPANY
7306 N. Linder Ave., Skokie, III. 60076 840 Cherry St., San Carlos, Calif. 94070 ·
• 331 Ε. 38th St., New York, Ν. Υ. 10016 13428 Wyandotte, North Hollywood, Calif. 91605
A NEW FLEXIBLE LOW-COST MODEL 160 SERIES DUAL COLUMN PROGRAMMED GAS CHROMATOGRAPHS A n e w c o n c e p t of high p e r f o r m a n c e a n d c o n v e n i e n c e in o p e r a t i o n — plus g r e a t flexibility — a w i d e selection of rise rates a n d f a s t e r b l o w - d o w n — all a t a n e w low c o s t — distinguish t h e n e w M o d e l 1 6 0 Series built a r o u n d a n e w basic c o l u m n o v e n d e s i g n .
(1) Weighing in of 0.3-1 mg. sam ples. (2) Introduction of the combustion b o a t into the combustion tube. (3) Adjustment of a digidial to the numerical value of the weighing. (4) Pressing of a button to s t a r t the combustion cycle. T h e entire electronic equipment for the integration of peak areas and conversion into percentage composition can be assembled from commercially available compo nents. T h e design of this a p p a r a t u s was described in detail by H o r s t W e i t k a m p and Friedhelm K o r t e [Chemie-Ingenieur-Technik 35, 429 (1963)]. Since then, a few changes were found desirable in order to analyze for substances which either are resistant to combustion or are
Welch vacuum pumps cover a w i d e range from 21 to 8,400 liters per minute and ultimates from 2 X 1 0 ~ 2 mm Hg (torr) to 1 X 1 0 ~ 9 mm Hg (torr) or better.
tUe.i& jj&cUu-ieA.:
A n entirely n e w a u t o m a t i c prepara t i o n gas c h r o m a t o g r a p h is included in t h e series w h i c h has 3 d i s t i n c t models and 4 additional combina t i o n s o f optional e q u i p m e n t . T h e out standing features of each represent a valuable c o n t r i b u t i o n t o t h e a r t and science o f gas c h r o m a t o g r a p h y . 3 5 . 0 0 . T o properly appraise t h e application v a l u e s of this n e w series w r i t e for M o d e l 1 6 0 D a t a S h e e t .
LOENCO
inc.
^?^ο^αβ^^$^£Λίΐ^£^ζά^^ΐ,ί2^β^ίσ& 2092
Ν.
LINCOLN AVE. / ALTADENA, CALIF. / 7 9 4 - 1 1 6 7
(AC
213)
Circle No. 11 on Readers' Service Card
VOL.
36, NO. 1 1 , OCTOBER 1964
·
91 A
