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Accuracy in Analytical Spectrophotometry

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Accuracy in Analytical Spectrophotometry Pat>licaf/on ^60 Standard Reference Materials: A/BS Special Accuracy in Analytical Spectrophotometry R. W. Burke and R. Mavrodineanu' Center for Analytical Chemistry National Bureau of Standards Washington, DC 20234 N & T °.f„ S,T*. ,P, ECH R.I.C. "WHENCE MIST Illllfl PUBLICATIONS OS 03703b •Retired, present address: 227 Almena Road. West Palm Beach, FL 33405 U.S. DEPARTMENT OF COMMERCE, Malcolm Baldrige, Secretary NATIONAL BUREAU OF STANDARDS. Ernest Ambler. Director Issued April 1983 Library of Congress Catalog Card Number: 83-600512 National Bureau of Standards Special Publication 260-81 Natl. Bur. Stand. (U.S.), Spec. Publ. 260-81,140 pages (April 1983) CODEN: XNBSAV Disclaimer: Certain trade names and company products are mentioned in the text or identified in an illustration in order to adequately specify the experimental procedure and equipment used. In no case does such identification imply recommendation or endorsement by the National Bureau of Standards, nor does it imply that the products are necessarily the best available for the purpose. PREFACE As mandated in 1901 by an act of Congress, a prime func- tion of the National Bureau of Standards (NBS) is to develop and maintain the capability for making accurate physical and chemical measurements on the various materials used in science and industry. One of the principal ways in which this mandate has been fulfilled is through the issuance of certified Standard Reference Materials (SRM's). These standards are used to transfer the accurate measurements made at NBS to the user and are frequently issued with detailed publications describing how these SRM's were produced and should be utilized. An NBS series of papers, of which this publication is a member, called the NBS Special Publication - 260 Series , is used for this purpose. Because of a demonstrated need for more practical trans- mittance standards, particularly for use in clinical chemistry, a program was initiated in 1969 to study the fundamental principles of optical transmittance and to develop the instrumentation necessary to insure its accurate measurement. This publication is a summary of the work undertaken during the last decade for achieving this objective. It contains a description of the instrumentation that was developed in the NBS Center for Analytical Chemistry for providing accurate transmittance measurements on solid and liquid samples, a summary of the SRM's that were produced and, in addition, brief descriptions of techniques and methodologies that were developed for the accurate chemical characterization of various materials by molecular absorption spectrometry. The scientific papers published in this field are also reviewed together with considerations for future developments. Inquiries concerning the technical content of this paper should be directed to the authors. Other questions concerned with the availability, delivery, price, and so forth will receive prompt attention from: Office of Standard Reference Materials National Bureau of Standards Washington, D.C. 20234 George A. Uriano, Chief Office of Standard Reference Materials Ernest L. Garner, Chief Inorqanic Analytical Research Division Center for Analytical Chemistry OTHER NBS PUBLICATIONS IN THIS SERIES Catalog of NBS Standard Reference Materials Yakowitz, H., Victh, D. L.. Heinrich, K. F. J., and (1981-83 edition), R. W. Seward, ed., NBS Michaelis, R. E., Standard Reference Materials: Spec. Publ. 260 (November 1981). Homogeneity Characterization on NBS Spectro- Michaelis, R. E., and Wyman, L. L. Standard metric Standards II: Cartridge Brass and Low- Reference Materials: Preparation of White Cast Alloy Steel, NBS Misc. Publ. 260-10 (December Iron Spectrochemical Standards. NBS Misc. 1965). COM74-II064" Publ. 260-1 (June 1964). COM74-I 1061" Napolitano, A., and Hawkins, E. G„ Standard Michaelis, R. E., Wyman, L. L.. and Flitsch, R.. Reference Materials: Viscosity of Standard Standard Reference Materials: Preparation of Lead-Silica Glass, NBS Misc. Publ. 260-11 NBS Copper-Base Spectrochemical Standards. (November 1966). NBS Misc. Publ. 260-11" NBS Misc. Publ. 260-2 (October 1964). COM74- Yakowitz, H., Vieth, D. L., and Michaelis. R. E., 11063" Standard Reference Materials: Homogeneity Michaelis, R. E., Yakowitz, H., and Moore, G. A., Characterization of NBS Spectrometric Stand- Standard Reference Materials: Metallographic ards III: White Cast Iron and Stainless Steel Characterization of an NBS Spectrometric Low- Powder Compact, NBS Misc. Publ. 260-12 Alloy Steel Standard. NBS Misc. Publ. 260-3 (September 1966). NBS Misc. Publ. 260-12" (October 1964). COM74-1 1060** Spijkerman, J. L.. Snediker, D. K... Ruegg, F. C, Hague. J. L. Mears. T. W.. and Michaelis. R. E.. and DeVoe. J. R., Standard Reference Mate- Standard Reference Materials: Sources of rials: Mossbauer Spectroscopy Standard for the Information, NBS Misc. Publ. 260-4 (February Chemical Shift of Iron Compounds, NBS Misc. 1965). COM 74- 11059 Publ. 260-13 (July 1967). NBS Misc. Publ. Alvarez, R., and Flitsch R., Standard Reference 260-13" Materials: Accuracy of Solution X-Ray Spectro- Menis, O., and Sterling, J. T., Standard Reference metric Analysis of Copper-Base Alloys. NBS Materials: Determination of Oxygen in Ferrous Misc. Publ. 260-5 (March 1965). PBI68068" Materials - SRM 1090, 1091. and 1092, NBS Shultz, J. I.. Standard Reference Materials: Misc. Publ. 260-14 (September 1966). NBS Misc. Methods for the Chemical Analysis of White Publ. 260-14" Cast Iron Standards. NBS Misc. Publ. 260-6 Passaglia, E., and Shouse. P. J. Standard Refer- (July 1975). COM74-1I068" ence Materials: Recommended Method of Use Bell, R. K... Standard Reference Materials: of Standard Light-Sensitive Paper for Calibrat- Methods for the Chemical Analysis of NBS ing Carbon Arcs Used in Testing Textiles for Copper-Base Spectrochemical Standards. NBS Colorfastness to Light, NBS Misc. Publ. 260-15 Misc. Publ. 260-7 (October 1965). COM74- (June 1967). (Replaced by NBS Spec. Publ. 1 1067" 260-41.) Richmond, M.S., Standard Reference Materials: Yakowitz, H.. Michaelis. R. E., and Vieth, D. L, Analysis of Uranium Concentrates at the Standard Reference Materials: Homogeneity National Bureau of Standards. NBS Misc. Publ. Characterization of NBS Spectrometric Stand- 260-8 (December 1965). COM74-1 1066** ards IV: Preparation and Microprobc Charac- Anspach, S. C. Cavallo. L. M. Garfinkel, S. B. terization of W-20% MO Alloy Fabricated by Hutchinson, J. M. R., and Smith. C. N., Stand- Powder Metallurgical Methods. NBS Spec. ard Reference Materials: Half Lives of Materials Publ. 260-16 (January 1969). COM74-1 1062" Used in the Preparation of Standard Reference Catanzaro. E. J.. Champion. C. E.. Garner, E. L., Materials of Nineteen Radioactive Nuclides Mannenko. G„ Sappenficld. K. M.. and Shields, Issued by the National Bureau of Standards W. R. Standard Reference Materials: Boric NBS Misc. Publ. 260-9 (November 1965). Acid: Isotopic and Assay Standard Reference COM74-1 1065" Materials. NBS Spec. Publ. 260-17 (February 1970). Out of Print I I i v Geller, S. B., Mantek, P.A.. and Cleveland. N. Geller, S. B., Standard Reference Materials: Cali- G., Standard Reference Materials: Calibra- bration of NBS Secondary Standard Magnetic tion of NBS Secondary Standard Magnetic Tape Tape (Computer Amplitude Reference) Using (Computer Amplitude Reference) Using the the Reference Tape Amplitude Measurement Reference Tape Amplitude Measurement "Process A-Model 2," NBS Spec. Publ. 260-29 "Process A, "NBS Spec. Publ. 260-18 (November (June 1971). COM71-50282 1969). (See NBS Spec. Publ. 260-29.) Gorozhanina, R. S., Freedman, A. Y., and Paule, R. C, and Mandel, J., Standard Reference Shaievitch, A. B. (translated by M. C. Selby), Materials: Analysis of Intcrlaboratory Measure- Standard Reference Materials: Standard ments on the Vapor Pressure of Gold (Certifica- Samples Issued in the USSR (A Translation tion of Standard Reference Material 745). NBS from the Russian). NBS Spec. Publ. 260-30 (June Spec. Publ. 260-19 (January 1970). PBI9007I" 1971). COM71-50283** Paule, R. C, and Mandel, J., Standard Reference Hust, J. G., and Sparks, L. L„ Standard Reference Materials: Analysis of Interlaboratory Measure- Materials: Thermal Conductivity of Electrolytic ments on the Vapor Pressures of Cadmium and Iron SRM 734 from 4 to 300 K, NBS Spec. Publ. % Silver, NBS Spec. Publ. 260-21 (January 1971). 260-31 (November 1971). COM7I-50563** COM 74- 1 1359" Mavrodineanu, R., and Lazar, J. W., Standard Yakowitz, H., Fiori, C. E., and Michaelis. R. E., Reference Materials: Standard Quartz Cuvettes, Standard Reference Materials: Homogeneity for High Accuracy Spectrophotometry, NBS Characterization of Fe-3 Si Alloy, NBS Spec. Spec. Publ. 260-32 (December 1973). 55 cents* Publ. 260-22 (February 1971). COM74-1 1357** SN0O3-O03-0 1213-1 Napolitano, A., and Hawkins, E. G.. Standard Wagner, H. L., Standard Reference Materials: Reference Materials: Viscosity of a Standard Comparison of Original and Supplemental Borosilicate Glass, NBS Spec. Publ. 260-23 SRM 705, Narrow Molecular Weight Distri- (December 1970). COM7I-00157** bution Polystyrene. NBS Spec. Publ. 260-33 Sappenfield, K. M., Marineko, G., and Hague, J. (May 1972). COM72-50526** L, Standard Reference Materials: Comparison Sparks, L. L., and Hust, J. G„ Standard Reference of Redox Standards, NBS Spec. Publ. 260-24 Materials: Thermoelectric Voltage, NBS Spec. (January 1972). COM72-50058** Publ. 260-34, (April 1972). COM72-50371** Hicho. G. E., Yakowitz, H., Rasberry, S. D.. and Sparks, L. L., and Hust. J. G.. Standard Refer- Michaelis. R. E„ Standard Reference Materials: ence Materials: Thermal Conductivity of A Standard Reference Material Containing Austenitic Stainless Steel. SRM 735 from 5 Nominally Four Percent Austenite, NBS Spec. to 280 K, NBS Spec. Publ. 260-35 (April 1971) Publ. 260-25 (February 1971). COM74-1 1356** 35 cents* COM72-50368** Martin. J. F., Standard Reference Materials: Cali, J. P., Mandel, J., Moore, L. J., and Young, D. National Bureau of Standards-US Steel Corpor- S., Standard Reference Materials: A Referee tion Joint Program for Determining Oxygen and Method for the Determination of Calcium in Nitrogen in Steel, NBS Spec. Publ. 260-26 Serum. NBS SRM 915. NBS Spec.
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