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John A. Dean: flame photometry
Rpeetmchimics Acta, 1901,Tel. 17, p 127. Pergamon Press Ltd. Printed in Northern Irebud
BOOK REVIEW
JOHN A. DEAN: Flame Photometry.
McGraw-Hill,
New York,
19f30. 354 pp, $11.50.
TO THE beginner in flame photometry, the large mass of papers, chapters, reviews and theses in this field can be overwhelming. His initial pleasure at finding so much information in print may soon be dampened by the large number of contradictory statements which appear in this literature. A few books have appeared which attempt to assess and discuss this copious information, but none has been entirely satisfactory. Flame Photometry, by JOHN A. DEAN, is a better than average attempt in this direction, but it does have some minor faults. Like the other books in this field, Flume Photometry considers, in the first chapters the ~str~ent~tion of flame photomet~, excitation of spectra, sources of interference, selection of operating conditions, and evaluation of data. In accordance with the author’s particular interests, this portion of the book includes a fifteen-page chapter on the use of organic solvents. A chapter on atomic absorption spectroscopy is also included, but it is unfortunately brief (four pages) in view of the growing number of applications of this new analytical technique. About half of the book provides detailed information on each of the elements that can be excited to emit radiation in the flame. Emission wavelengths, sensitivities, optimum excitation conditions, wavelengths for background correction, and sources of interference are given for each of these elements when the data are available. The last three chapters discuss clinical applications and analysis of soils, plant materials, plant nutrients, cement and glass. A liberal use of illustrations and a bibliography with about 800 entries add to the value of this work. Much of the specific information given in this book (e.g. sensitivities) applies to a Beckman DU spectrophotometer with an oxygen-acetylene flame and a photomultiplier detector. This will limit somewhat the value of the data for users of other instruments. There are also several errors, some of which could have been avoided by more careful proof-reading. An example of this is the sentence on p. 139: “As the number of unexcited atoms is always a very small fraction of the total at a flame temperature below 2250”K, the number of unexcited atoms is virtually equal to the number aspirated.” Other errors include the statement, on p. 199, that the effect of the continuum from sodium can be eliminated by use of a didymium filter. Only scattered light, not continuous radiation, can be reduced in this way. The book also contains some inconsistencies. On p. 99, for example, it is said that increasing the slit width “will probably improve the emission sensitivity of molecular band systems relative to the flame background reading,” but on p. 125 we are told that “with broad emission bands the ratio of metal emission to flame background is nearly independent of slit width.” The section on excitation of atomic spectra may be confusing to the neophyte, since it is not always clear whether absorption or emission of radiation is being considered. The chapter on interferences does not always distinguish clearly between background from flame bands, from scat.tered light and from alkali metals. Alkali metal background is first mentioned in the chapters which discuss the spect,ra of the individual elements. Even there, the data on background sre taken from a paper published in 1894, without reference to more recent studies. On the whole, however, DEAN has done well in correlating a great deal of information from the literature and from his own experience. The book should be of considerable help to those who are just starting in flame photometry and to others who have done some work in this field but who wish to improve their understanding of the fundamentals. The faults are small enough to be corrected easily in future printings. The publishers might also consider removing from the dust jacket the inaccurate statement that this book is “the first full-length treatment” of flame photometry. MARVIN MARGOSHES 127
BOOK REVIEW
JOHN A. DEAN: Flame Photometry.
McGraw-Hill,
New York,
19f30. 354 pp, $11.50.
TO THE beginner in flame photometry, the large mass of papers, chapters, reviews and theses in this field can be overwhelming. His initial pleasure at finding so much information in print may soon be dampened by the large number of contradictory statements which appear in this literature. A few books have appeared which attempt to assess and discuss this copious information, but none has been entirely satisfactory. Flame Photometry, by JOHN A. DEAN, is a better than average attempt in this direction, but it does have some minor faults. Like the other books in this field, Flume Photometry considers, in the first chapters the ~str~ent~tion of flame photomet~, excitation of spectra, sources of interference, selection of operating conditions, and evaluation of data. In accordance with the author’s particular interests, this portion of the book includes a fifteen-page chapter on the use of organic solvents. A chapter on atomic absorption spectroscopy is also included, but it is unfortunately brief (four pages) in view of the growing number of applications of this new analytical technique. About half of the book provides detailed information on each of the elements that can be excited to emit radiation in the flame. Emission wavelengths, sensitivities, optimum excitation conditions, wavelengths for background correction, and sources of interference are given for each of these elements when the data are available. The last three chapters discuss clinical applications and analysis of soils, plant materials, plant nutrients, cement and glass. A liberal use of illustrations and a bibliography with about 800 entries add to the value of this work. Much of the specific information given in this book (e.g. sensitivities) applies to a Beckman DU spectrophotometer with an oxygen-acetylene flame and a photomultiplier detector. This will limit somewhat the value of the data for users of other instruments. There are also several errors, some of which could have been avoided by more careful proof-reading. An example of this is the sentence on p. 139: “As the number of unexcited atoms is always a very small fraction of the total at a flame temperature below 2250”K, the number of unexcited atoms is virtually equal to the number aspirated.” Other errors include the statement, on p. 199, that the effect of the continuum from sodium can be eliminated by use of a didymium filter. Only scattered light, not continuous radiation, can be reduced in this way. The book also contains some inconsistencies. On p. 99, for example, it is said that increasing the slit width “will probably improve the emission sensitivity of molecular band systems relative to the flame background reading,” but on p. 125 we are told that “with broad emission bands the ratio of metal emission to flame background is nearly independent of slit width.” The section on excitation of atomic spectra may be confusing to the neophyte, since it is not always clear whether absorption or emission of radiation is being considered. The chapter on interferences does not always distinguish clearly between background from flame bands, from scat.tered light and from alkali metals. Alkali metal background is first mentioned in the chapters which discuss the spect,ra of the individual elements. Even there, the data on background sre taken from a paper published in 1894, without reference to more recent studies. On the whole, however, DEAN has done well in correlating a great deal of information from the literature and from his own experience. The book should be of considerable help to those who are just starting in flame photometry and to others who have done some work in this field but who wish to improve their understanding of the fundamentals. The faults are small enough to be corrected easily in future printings. The publishers might also consider removing from the dust jacket the inaccurate statement that this book is “the first full-length treatment” of flame photometry. MARVIN MARGOSHES 127