New Books The following may be ordered prepaid from the Superintendent of Documents, U.S. Government Printing Office, Washington, D.C. 20402. Include title and stock number. {The instructions given above for foreign orders apply.) Standard Reference Materials: A Referee Method for the Determination of C a l c i u m i n S e r u m . SD Catalog No. 013.10:260-36. J . Paul Cali, J o h n M a n del, Larry M o o r e , a n d D o n a l d S. Y o u n g . 136 p a g e s . 1972. $1.25
This report gives the first attempt to bring about a referee method of analysis (a method of known accuracy based in part on the use of standard reference materials) in clinical chemistry. Despite the shortcomings that a careful study of the methodology employed reveals, the authors believe they can say "with some assurance" that "a referee method for the analysis of calcium in serum or physiological solutions has been achieved." Subject to the limitations and provisos stated, this can be done to within 2% of the "true or absolute" value.
They houe
Thermistors ! Bronwill's two new constant temperature circulators have them. These semi-conductor sensors give instant response over a broad range . . . maintain uniformity better than ±0.01 °C . . . certified. No thermoregulators to change for different ranges, no breakage, no chance of mercury contamination! Just dial directly the dual controls (coarse and fine) to select temperature. Heater wattage is automatically proportioned to assure "straight-line" temperature control (off-on time equal). Solid state circuitry is designed to minimize RF interference.
Effects of C h e m i c a l s o n A q u a t i c L i f e . W a t e r Q u a l i t y C r i t e r i a Data B o o k , Vol 3. No. 18050GWV05/71. H. T. K e m p , J . P. A b r a m s , a n d R. C. O v e r b e c k . Batelle, C o l u m b u s , Ohio. 500 pages.
1971. $3.75 This report is a comprehensive compilation of information on the effects of chemicals on fish and about 5000 aquatic organisms. It is based on data from the technical literature available through 1968 (about 1000 references). The data are arranged in tabular form and include: the name of the chemical; aquatic organism affected; technique by which toxicity was determined; field location where reference study was conducted ; toxicity of active ingredient; name of researcher; and date when study was completed. The report also includes discussions on bioassay of fish and other aquatic organisms, marine bioassay, field assessment, and factors affecting chemical toxicity. T h e I n t e r n a t i o n a l S y s t e m of U n i t s ( S I ) . SD Catalog No. C13.10:330/2. Chester H. Page a n d Paul Vigoureux. 45 pages.
1972. 300. This document is the second edition of an official description of the metric system in its present-day form. This new edition is brought up-to-date with the decisions of the 14th General Conference of Weights and Measures and takes into account the recommendations proposed by the Consultive Committee for Units.
Variabel . . .
today's most advanced immersion circulator. Converts any container up to 30 liters into a constant temperature bath. Circulates up to 12 l/min. Temperature range, ambient to +120°C . . . below ambient with accessory cooling coil.
Thermomant . . .
reservoirtype, controls liquid temperature in closed systems or open baths up to 25 liters. Dual action: suction, 8 l/min.; pumping, 10 l/min. Choice of 1000 or 2000 watts of maximum power to minimize "overshoot". Temperature range, ambientto +100°C; builtin cooling coil for below ambient.
Plus the rest of the full line of Bronwill CTC'S C T C J r . • · · the economical i m m e r s i b l e CTC that converts any c o n t a i n e r up to 15 liters into a c o n s t a n t t e m p e r a t u r e b a t h . C T C 2 0 . . · the ultra-reliable, accurate, i m m e r s i b l e CTC—now w i t h all s o l i d state c i r c u i t r y . It heats, c i r c u l a t e s and p u m p s up to 12 l i t e r s / m i n u t e . C T C S r . . . . the high temperature (up to 200°C), heavy duty i m m e r s i b l e CTC that heats, c o n t r o l s , p u m p s o i l or w a t e r in any c o n t a i n e r w i t h a c a p a c i t y up to 60 liters. C T C 2 5 A d a p t - O - C o o l ™ . . . refrigerated coil unit fits most c i r c u l a t o r s or can be used a l o n e . O p e r a t e s quietly f r o m — 2 5 ° C up to 40°C ( c o m p r e s s o r reservoir p r o t e c t s refrigerant system a b o v e ambient). E x c e p t i o n a l efficiency, o p t i m u m p u m p - d o w n times.
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Albuquerque · Anchorage · Atlanta · Baltimore · Boston · Buffalo · Columbus · Denver Detroit · Honolulu · Houston · Kansas City · Los Angeles · New York City Phoenix · Portland · Rochester · Salt Lake City · San Francisco · Seattle CIRCLE 217 ON READER SERVICE CARD A N A L Y T I C A L CHEMISTRY, VOL. 4 4 , NO. 1 1 , SEPTEMBER 1 9 7 2
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