4 principal uses me: Π CLASSIFYING laboratory quantities of fine

mater ia ls for product or new mater ia l research.

E J j CONTROLLING industrial processes using I M I or producing fine materials.

Ο DETERMINING the separating efficiency of air cleaners.

f l PRE-TESTING dust collector requirements.

DETERMINE PARTICLE SIZE DISTRIBUTION below 60 m ic rons , in ma te r i a l s such as:

Bery l l i um Powder G r i n d i n g Sand Cata lys ts Me ta l Oxides Ceramic Powders Penic i l l in Chemica ls Po l ymers D ia tomaceous Earth Powde red Meta ls Drugs Mi lk Sol ids Dry Powders S t a n d a r d Dust Fly Ash Samp les

H A R R Y W. DIETERT CO. CONTROL EQUIPMENT

9 3 3 0 R o s e l a w n • D e t r o i t 4 , M i c h .

Send me details on Micro-Particle Classifier

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Address_

Company _

City .S ta te .

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6 2 A · ANALYTICAL CHEMISTRY

NEW BOOKS

Spectroscopy, held at the University of London from March 28 to 31 was at­tended by over 300 delegates including 65 from overseas countries. Emi­nent authors were invited to review the progress in many fields in order to give a balanced appreciation of spectros-copy as it stands today. This book is a collection of these lectures. The titles and authors arc : Trends in the Chemi­cal Applications of Spectroscopy bv H. W. Thompson, (F.R.S., St. John's College, Oxford) ; Atomic Absorption Spectroscopy by A. Walsh (C.S.I.R.O., Melbourne) ; Some Aspects of Atomic Absorption by R. L. Warren (Mid­dlesex Hospital) ; X-Bay Fluores­cence Analysis by Η. Ν. Wilson and B. J. Otter (LCI., Billingham) ; Nu­clear Magnetic Besonance by R. E. Richards, (F.R.S., Lincoln College, Ox­ford) ; A Study of Nuclear Magnetic Resonance Performance Parameters by R. B. Williams (Humble Oil and Re­fining Co., Texas) ; The Method and Technique of Electron Resonance and Its Application to Metal Complexes by D. J. E. Ingram (University College of North Staffs) ; Electron Spin Reso­nance of Free Radicals by D. H. Whiff en (National Physical Labora­tory) ; Free Radical Spectroscopy bv Β. Ν. Dixon (Sheffield University)'; The Spectrophotometry of Free Radi­cals in Flames by T. M. Sugden (Cam­bridge University) ; Optical Absorption Spectra of Oriented Free Radicals bv G. W. Chantry (National Physical Laboratory) ; Far Infra-Red Spectros­copy by G. R. Wilkinson, S. A. Inglis, and C. Smart (King's College, London) ; Rotation in Solution by W. J. Jones and N. Sheppard (Cambridge University) : The Origins of Group Frequency Shifts. Pt. II . The In­fluence of Inductive Effects and of Non-Bonded Interactions on Infra-Bed Group Frequencies, by L. J. Bellamy (E.R.D.E., Waltham Abbey) ; Fac­tors Affecting the Characteristics of Infra-Red and Raman Vibrational Bands by H. W. Thompson, (F.R.S., St. John's College, Oxford) ; Develop­ments in Applied Spectroscopy by V. Z. Williams (Perkins-Elmer Corp.) ; Some Uses of Electronic Computing Ma­chines in Spectroscopy by A. D. Booth (Birkbeck College) ; Solvent Effects on Infra-Bed Spectra of Inorganic Com­plexes by D. M. Adams (I.C.I., The Frythe) ; Vacuum Ultra-Violet Spectra and Photoionization of Molecules and Radicals by W. C. Price, F.R.S., R. Bralsford, and D. M. Boessler (King's College, London) ; The Electronic Spec­tra of Small Polyatomic Molecules with Especial Reference to the Absorption Spectrum of Nitrogen Dioxide by R. K. Ritchie, A. D. Walsh, P. A. Warsop

ACCESSORIES INCREASE THE CAPABILITIES OF PERKIN-ELMER'S MODELS 421, 221 AND 21 INFRARED SPECTROPHOTOMETERS

Sample preparation and handling are probably the most critical operations in infrared spectroscopy. That's why second best won't do when you choose sampling accessories. You'l l realize the best per­formance from your Perkin-EImer Mode! 421,221, or21 Spectrophotometer with Perkin-Elmer's quality cells and attachments, no matter what investiga­tions you're undertaking.

FOR GAS SAMPLING: Perkin-EImer cells include

a wide variety of window and body materials, in

path lengths from 2 centimeters to 40 meters,

Pressure and Ijeated cells are also avai lable.

FOR LIQUID SAMPLING: Cells are provided in

demountable or sealed versions, in various dis­

crete path lengths, for regular or micro sampling.

Special cells with micrometer adjustments for vary­

ing path length are afso avai lable, as well as

heated cells for special studies.

FOR SOLID SAMPLING: The KBr pressed-disc

technique is facil i tated by special-purpose acces­

sories: dies, holders, vibrators—for preparing and

analyzing samples in standard 13mm and micro

KBr discs.

Perkin-EImer also has special accessories that equip the Models 421, 221 and 21 to handle other un­usual sampling problems. And-most large-instru­ment accessories are adaptable to P-E's low-cost line of IR spectrophotometers. For complete de­tails, write to Instrument Division, Perkin-EImer Cor­porat ion, 751 Main Avenue, Norwalk, Connecticut.

Variable Path Liquid Cell

KBr Micro-Die

PERKIN-ELMER Circle No. 185 on Readers' Service Card

Circle No. 182 on Readers' Service Card S

HOW I N D U S T R I A L U S E S T H E

DIETERT-DETROIT (BAHCO)

MICRO-PARTICLE CLASSIFIER

1 -Meter Gas Cell