New Books
mental theoretical principles upon which these techniques are based. Electroanalytical principles are proving useful in such diverse fields as electroorganic synthesis, fuel cell studies, and radical ion formation, as well as with such problems as the kinetics and mechanism of electrode reactions and the effects of electrode surface phe nomena, adsorption, and the electrical double layer on electrode reactions. Physical Measurement and Analysis of Thin Films. Vol. 2. E. M. Murt and W. G. Guldner, Editors, xi + 194 pages. Plenum Press, 227 West 17th St., New York, Ν. Υ. 10011. 1969. $12.50
IR Micro Sampling Made Easy Simplify and speed your infrared micro sampling techniques with these efficient accessories perfected by Barnes — the most com plete line on the market. Ο All-Mirror Beam Condenser — minimal energy loss, unlimited spectral range, no fogging, beam reduction at sample point 1 χ 4mm. Strong spectra from samples as small as 0.2,u.l. Ο New Liquid Precision Microcells — leaktight, volumes as low as 0.7^1, six pathlengths from .015mm, seven different window materials. Ο Unique KBr Die — with new paper inserts so handy to speed micro sample preparation. Die doubles as GC fraction col lector. Ο Micro Specular Reflectance Accessory—high power, low loss reflecting optics with 3 to 1 beam reduction at sample point. Vary sample area with micro masks provided. Ο
Complete Line of Cells — Ultra Micro Cavity and Gas Cells, Micro Mull and KBr Pellet Holders that insure superior spectra.
Whatever your IR micro sampling needs, Barnes has all the ac cessory answers. Send today for new 8-page booklet " M i c r o Sampling Made Easy."
BARNES ENGINEERING 30 Commerce Rd./Stamford,
Conn. 06902/Phone
Circle No. 88 on Readers' Service Card
94A
·
ANALYTICAL CHEMISTRY
(203) 348-5381
These selected papers from the 1967 Eastern Analytical Symposium, written by recognized authorities in their fields, present a comprehensive review of the latest instrumental techniques for thinfilm measurement and analysis. A va riety of highly specialized applications and modifications of conventional methods is described, and a complete review of X-ray methods is given. Other topics covered include the use of radioisotopes, the electron microprobe, nondestructive optical techniques, and a special report on density determina tion by a beta-backscatter technique. In view of the widespread interest in thin-film technology and its current ap plications in the electronics and aero space industries, this volume should prove valuable to all those engaged in applied research with thin films. U. S. Government Publications The following publications can be ordered from the Superintendent of Documents, U. S. Government Printing Office, Washington, D. C. 20402; the Clearinghouse for Federal Scientific and Technical Information, Springfield, Va. 22151; or local U. S. Dept. of Com merce Field Offices. Rapid Analysis of Antifreeze Using GasLiquid Chromatography (AD-686 289). G. G. Esposito and R. G. Ja mison. April 1969. 18 pages.
Describes an analytical procedure for identification and determination of gly cols and ether-alcohols as they occur in used and unused antifreezes. Determination of Polyhydric Alcohols in Alkyd Resin by Gas-Liquid Chroma tography (AD-685 821). G. G. Es posito. March 1969. 19 pages.
Describes a procedure that can be used for identifying a broad spectrum
DIFFICULT HIGH VACUUM APPLICATIONS?
New Books
of polyhydric alcohols and quantita tively determining polyols. Sample manipulation is minimal and a simulta neous determination is made with resins containing more than one polyol. Investigation of High-Temperature Gas Chromatography Substrates (AD-684 558). W. D. Ross. November 1968. 54 pages.
Develops a gas chromatographic method for analysis of small amounts of chromium in two ferrous alloys. High Resolution with Nondispersive X-Ray Spectrometers (AD-683 706). D. W. Aitken. July 1968. 23 pages.
Discusses resolution in the X-ray en ergy region, which spans the energy range from about 1 keV to 100 keV and corresponds to the wavelength region extending from about 10 A down to about 0.1 A. Nuclear Techniques in On-Stream Anal ysis of Ores and Coal (ORO-298018). J. R. Rhodes et al. September 1968. 96 pages.
T h e s e clean, hydrocarbon free, purely mechanical vacuum pumps for attaining high and ultra-high vacuum offer many advantages over other pumping methods. Turbo-molecular pumps attain extremely clean vacuum in the 10~ 6 to Ι Ο - 7 decades very rapidly and have a blank-off pressure of 1 - 2 χ Ι Ο - 9 torr or lower. Turbos are non-contam/nat/ng and self-cleaning... remove hydrocarbons from the system in unlimited quantities without use of cold traps... pump all gases, including the noble gases at any point within operating range... simplify roughing problems... do not use nor produce extremely high voltages... use no pumping fluids... are not damaged by, and recover rapidly from exposure to high pres sure ... will not become overloaded and do not "bury" gases, so cannot re-eject them into the system... offer easy leak detection, as they pump helium from 10~2 to 10~9 torr. If your application requires high to ultra-high vacuum, a Welch Turbo Molecular Pump will eliminate many of the disadvantages found in other pumping methods.
Write for Turbo Bulletin, or call 3 1 2 / 6 7 7 - 0 6 0 0 for advantages for your specific application.
WELCH VACUUM PUMPS Model No. 3103
SARGENT-WELCH SCIENTIFIC COMPANY
7300 N. UNDER AVENUE · SK0KIE, ILLINOIS 60076 Circle No. 68 on Readers' Service Card
96A
·
ANALYTICAL CHEMISTRY
Determines aluminum and silicon by neutron activation using a radioisotope neutron source; studies enhancement in sensitivity of neutron activation anal ysis obtained by recirculating the sam ple between source and detector; and determines calcium and iron in cement raw mix by X-ray fluorescence using radioisotope X-ray sources. Report also reviews work done prior to May 1967. A New Method for Direct Measurement of Spectral Line Strengths and Widths (AD-686 145). R. E. Meredith and N. F. Kent. April 1969. 80 pages.
Develops a procedure that makes maximum use of the moderate-to-highresolution capability available in most spectroscopic laboratories. Nuclear Techniques in On-Stream Anal ysis of Ores and Coal (ORO-2980-18). J. R. Rhodes et a/. September 1968. 96 pages.
Determines aluminum and silicon by neutron activation using a radioisotope neutron source ; studies enhancement in sensitivity of neutron activation analy sis obtained by recirculating the sample between source and detector; and de termines calcium and iron in cement raw mix by X-ray fluorescence using radioisotope X-ray sources. Report also reviews work done prior to May 1967.
