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WITH ANALTECH PRE-COATED, PRE-SCORED TLC UNIPLATES,m you can buy one size and use it as a standard 20 χ 20 cm plate . . . or as economical 5 χ 20 cm plates with unique con venience and savings up to 30% over conventional 5 χ 20 cm plates. ANALTECH offers the widest selection of TLC adsorbents, p r e p a r e d in t h e c l a s s i c a l manner. A b s o l u t e u n i f o r m i t y for superior reproducibility is Unconditionally Guaranteed. Same Day shipment.
Books Documents, U.S. Government Print ing Office, Washington, D.C. 20402. Foreign remittances must be in U.S. exchange and should include an addi tional 25 % of the publication price to cover mailing costs. Accuracy in Trace Analysis. S. D. Cat alog No. C13.10:422. 1976. $20
The two-volume hardcover NBS Special Publication 422 contains 100 papers presented at the 7th Materials Research Symposium sponsored by the NBS Institute for Materials Re search October 7-11,1974. At that symposium, 400 scientists from 17 countries discussed the latest informa tion available on trace chemical analy sis. How accurate are measurements of chemicals that are present only in very small quantities in foods, tissues, water, air, and other materials? What factors contribute to accurate mea surements? How can the reliability of trace chemical measurements be im proved? Answers to these questions as well as requirements for accurate mea surements of trace chemicals by regu latory agencies are examined in detail.
Company Manual AA Methods Manual. 300 pages. Fisher Scientific Co., 711 Forbes Ave., Pitts burgh, Pa. 15219. 1976. $65
tion to flame spectrometry, prepara tion and storage of standards, meth ods of standard additions, preferred ashing techniques for trace metal re covery in organics and biological ma terials, four detailed procedures for solvent extraction of metals, reference texts for atomic absorption, and weight and volume conversion factors.
ASTM Publications The following are available from the American Society for Testing and Materials, 1916 Race St., Philadel phia, Pa. 19103 (USA, Canada, and Mexico add 3% shipping charges. Other countries add 5%) 1976 Annual Book of ASTM Standards, Part 30 on Soap, Engine Coolants, Pol ishes, Halogenated Organic Solvents, Activated Carbon, and Industrial Chemicals. 948 pages. 1976. $31
Part 30 contains 192 ASTM stan dards of which 13% are new, revised, or changed in status since the 1975 edition. This book is brought up-todate and published annually. Among the new standards in this book are tests for chloride in trichlorotrifluoroethane, total acid number of trichlorotrifluoroethane, total residue in trichlorotrifluoroethane, water content of trichlorotrifluoroethane with Karl Fischer reagent, purity of trichlorotri fluoroethane, and specific aqueous conductance of trichlorotrifluo roethane, plus a specification for water emulsion floor polish remover.
1976 Annual Book of ASTM Standards, Part 41 on Statistical Methods, Space Simulation, Particle Size Measure ment, Determination of Nonmetallic Materials. 868 pages. 1976. $27
FULL LINE 32-PAGE TLC CATALOG covering plates and accessories.
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This manual, published by the Jarrell-Ash Division, contains important data on all elements that can be ana lyzed with any type of AA system. In dividual "element sheets" present basic parameters for each analysis, possible interferences, background corrections, preparations of standard solutions, extraction procedures, spe cial comments on ashing or sample preparation, and complete informa tion on the element's flame emission properties. Following each element section is a number of detailed AA an alytical methods for that element in various types of samples. The back ground section includes an introduc
CIRCLE 6 ON READER SERVICE CARD 244 A · ANALYTICAL CHEMISTRY, VOL. 4 9 , NO. 2, FEBRUARY
1977
The 112 ASTM standards methods of testing presented in this book cover diverse areas such as thermal analysis, laboratory balances, filtration materi als, glassware laboratory apparatus, hydrogen ion determination, hydrom eters, microchemical apparatus, statis tical methods, and particle size mea surement, to mention only those of in terest to analytical chemists. Among the new standards in this edition are a test for cathodic disbonding of pipe line coatings subjected to elevated or cyclic temperatures, and a recom mended practice for specifying limits for fading and discoloration of nonme tallic materials.
