NEW PRODUCTS perature b a t h s or as a lubricant with a low vapor pressure a n d high flash point. T h e oil consists of purified diethyl hexylphthalate. I t has a boiling point of 126° C. a t 0.01 m m . of mercury. Flash point is 380° F . I t can be used to produce a n ultimate v a c u u m of 2 X 10" 7 m m . of m e r c u r y a t 25° C. in a threestage fractionating p u m p , according t o t h e manufacturer. 7
difficult stains a n d t o prevent t h e spotting of glassware caused b y quick machine drying operations. 6
Vacuum Pump Oil An oil for diffusion p u m p s t h a t permits high v a c u u m t o b e a t t a i n e d without the use of t r a p s involving liquid air or charcoal is being m a r k e t e d b y A. Daigger & Co. T h e oil can b e used in high vacuum diffusion p u m p s a n d differential manometers, or employed as a heat transfer medium in constant tem-
Bottle Pump A p u m p for use in removing distilled water and other liquids from carboys,
tanks, and other containers is being offered by Barnstead Still & Sterilizer Co. I t is designed for protecting the contents from contaminating matter— such as air-borne bacteria, dust, mist, vapors, and alkali or acid gases—which may enter during time of storage or when liquids are being removed. Outside air is cleaned by passing through a filter which removes or absorbs impurities before the air can enter the container to replace liquid being pumped out. 8 Filtration Unit
A borosilicate glass unit which can serve for both ultrafiltration and bacteriological filtration is being distributed by E. Machlett & Son. Since the VirTis UltraBac filter is of all-glass construction, no rubber or metal contacts solutions to contaminate the filtrate. A vacuum port is provided in the collection flask and a pressure port, as well as a port for filling, is provided in the upper reservoir, so that the unit can be operated with either pressure or vacuum. Machlett points out that the filter can be autoclaved as a unit. I t is available in two sizes: one equipped with a Vs X 8 inch glass candle and a 125ml. reservoir and a larger unit with a 1 X 8 inch candle and a 700-ml. reservoir. 9
THIS FLEXIBLE PLASTIC TUBING IS STANDARD IN L A B O R A T O R I E S EVERYWHERE
• • • • •
it is glass clear it is non-toxic it is sterilizable it is chemically-resistant it is available in 58 sizes
Fat Stability Apparatus
TYGON TUBING a product of
THE
U. S. S T O N E W A R E C O . Akron 9 , Ohio
Plastics and Synthetics Division 16-E
For further information, circle number 56 A on Readers' Service Card, page 51 A
56 A
An a p p a r a t u s for determining t h e keeping time of fats a n d oils b y t h e activ a t e d oxygen m e t h o d is available from A r t h u r S. L a P i n e & Co. I n addition t o its use for animal fats, i t can be used t o determine t h e stability of vegetable a n d cooking oils, shortening, and animal feeds t h a t contain fats. I n t h e test operation, clean a i r is bubbled through t h e sample a t a cons t a n t rate u n t i l rancidity develops. A b a t h maintains t h e sample a t a cons t a n t t e m p e r a t u r e of 208° F . , and t i m e of aeration u n t i l inception of rancidity is recorded. Peroxide values are then determined b y chemical tests a n d plotted against aeration time t o show keeping t i m e . T h e constant t e m p e r a t u r e b a t h portion of t h e a p p a r a t u s includes a circulating p u m p , thermoregulator, t w o For further information, s e e coupon on page SI A ANALYTICAL
CHEMISTRY