Correction. Determination of Double Bond Position in Conjugated

the Conventional and Presént Methods. « _a18o,°. %,_ sample conventional method present method. JSW6. TTW. AAGC. -1.16 ± 0.04 ( = 5). -10.02 ± 0...
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ANALYTICAL CHEMISTRY, VOL. 58, NO. 6, MAY 1986

Table I. Measurements of ~ 3 ~ of ~ Three 0 Water Samples by 4 the Conventional and Present ,Methods sample

PO,' L conventional method present method

JSWb TTW AAG'

-1.16 f 0.04 (n = 5) -10.02 f 0.03 (n = 8) -17.19 f 0.04 (n 5)

-1.18 f 0.04 (n = 6) -10.02 f 0.03 (n = 7) -17.22 f 0.02 (n = 7)

Statistic errors indicate the standard deviation (la). bDistilled Japan Sea water. Distilled Antarctic glacier.

runs, which is identical with that of the conventional method. In addition, over 100 samples have been tested by the present and conventional methods and the differences have been found to be within fO.l%o (la). The agreement of the 6180 values measured by the two methods is sufficiently good within the experimental error. The present method is recommended for general use.

1275

ACKNOWLEDGMENT We thank Hitoshi Sakai and Harue Masuda of Ocean Research Institute, University of Tokyo, for providing the antarctic glacier sample. Registry No. leg,14797-71-8;HzO, 7732-18-5; COz, 124-38-9.

LITERATURE CITED (1) Epstein, S.; Mayeda, T. Geochim. Cosmochim. Acta 1053, 4 , 2 13-224. (2) Gonfiantini, R. "Stable Isotope Hydrology"; Gat, J. R.,Gonfiantlni, R., Eds.; IAEA Vienna, 1981; Chapter 4. (3) Roether, W. Int. J . Appl. Radlat. Isot. 1970, 2 1 , 379-387. (4) Chiba, H.; Sakai, H.; Yasutake, M. Pap. Inst. Therm. Spring Res. Okayama Univ. 1085, 56, 27-34. (5) Craig, H. Geochim. Cosmochim. Acta 1057, 72, 133-149. (6) Craig, H. Science (Washington,D.C.) 1081, 133, 1833-1834. (7) Vogel, J. C.; Grootes, P. M.; Mook, W. 0. 2. Phys. 1970, 230, 225-238.

RECEIVED for review August 21, 1985. Accepted November 27, 1985.

CORRECTION Determination of Double Bond Position in Conjugated Dienes by Chemical Ionization Mass Spectrometry with Isobutane R. E. Doolittle, J. H. Tumlinson, and A. Proveaux (Anal. Chem. 1985,57, 1625-1630). On page 1627, in Table 11, in the vertical column headed by [b]+in the section of the table labeled R = CHzOCHOand in the horizontal row entitled 7,l; Z,Z, the entry that reads 155 (3) should read 115 (3). On page 1629, in Table 111, in the vertical column headed [a]+ in the section of the table labeled R = CHO and in the horizontal row entitled 4,8;Z$, the entry that reads 113 (98) should read 113 (48). The correction of the error on page 1629 has direct implications in the discussion (page 1628, paragraph 4) of patterns of the relative abundances of ions [a]+and [b]+from the four pwible isomers of each conjugated diene since i t removes one of the exceptions to the observation that in the Z,E and E,Z isomers those ions [a]' and [b]+ from cleavage at or near the E bonds are in greatest abundance. This observation is under active investigation a t present.