Showing papers in "Analytical Chemistry in 1974"

Inductively coupled plasma-optical emission analytical spectrometry

Abstract: A compact inductively coupled plasma-optical emission system for the trace determination of metallic elements in solution is described. Theoretical considerations are presented to determine operating parameters that agree well with the empirically determined values. The aerosol desolvation system commonly used with this type of source has been eliminated, and pneumatic nebulization is employed in place of the more elaborate ultrasonic method. Some characteristics of the plasma are reported. Detection limits are in the range 0.1-- 10 ng/ml for most elements studied. The present facility is readily adaptable to simultaneous multi-element trace analysis. (auth)

Preservation of dilute mercury solutions

Abstract: Distilled water solutions containing 0.1 - 10.0 ng Hg/ml were stored for ten days in glass and polyethylene containers. Those which were untreated or treated with HNO/sub 3/, H/sub 2/SO/sub 4/ + KMnO/sub 4/ or K/sub 2/Cr/sub 2/O/sub 7/ lost substantial fractions of their mercury in this period. Solutions stored in polyethylene and treated with 5% (v/v) HNO/sub 3/ + 0.05% Cr/sub 2/O/sub 7//sup -2/ stayed at full strength for at least ten days. Solutions stored in glass and treated with 5% (v/v) HNO/sub 3/ + 0.01% Cr/sub 2/O/sub 7//sup -2/ stayed at full strength for as long as five months. The causes of losses in distilled and natural water samples are discussed. 9 references, 9 figures.

Mode-locked laser Raman spectroscopy. New technique for the rejection of interfering background luminescence signals

Abstract: st ra te the applicability of the TFV-ICP system to the analysis of samples over a n extended concentration range. T h e curve covers the four-decade concentration range of 0.001 to 10 fig Be/ml or from 2.5 X 10-11 t o 2.5 x 10-7 gram of Be. Discussion. A comparison of the TFV-ICP detection limits reported in Table I1 with t h e best values so far reported for the introduction of nebulized solution into the plasma shows t h a t the TFV-ICP system is superior by 1 to 2 orders of magnitude. This appears to be the result of the increased concentration of the analyte, already desolvated and vaporized by the filament, passing through the axial channel of the plasma per unit t ime. T h e same mechanism is utilized in AAS and AFS when filament vaporization is performed, bu t for these techniques, the free a toms must be produced a t the filament surface whereas for the plasma system it is only necessary to vaporize the analyte elements; the dissociation and excitation occur in the plasma. t /i' 1 0 U d oooo1 0001 0 01 01 10 10 0 Concentration (+Q B c l m l )

Analytical electrochemistry: methodology and applications of dynamic techniques

Abstract: (129) Robinson. A. L., S b n c e , 197, 148 (1977) (130) Rudman, R.. "Low-Temperature X-Ray Diffraction: ADDaratus and Techniques", Plenum Press, New York, N.Y., 1976. (131) Sato, S., Bunseki Kiki, 14, 271 (1976). (132) Schiferl, D., Rev. Sci. Instrum., 48, 24 (1977). (133) Scott, R. W., Treatise Coat., 2, 591 (1976). (134) Shevchik, N. J., Phil. Mag., 35, 1289 (1977). (135) Sims, J. R., Biumenthal, R. N., High Temp. Sci, 8, 99 (1976). (136) Siota, Y., Yokota, M., Kakizaki, A., Mitsui, T., Wakabayashi, K., Namba, K., Wada, E., Tagawa, H., Kurita, K., et al., Jpn. J . Appl. Phys., 16. 215