Photoacoustic analysis

Step-growth reactions, 24 16 Step-scan ftir photoacoustic analysis, 19 564... 

Stage I Parallel and quasi-parallel analytical techniques IR thermography Photoacoustic analysis Photothermal deflection... 

J.R. Parker, Photoacoustic Analysis of Ethylene-Propylene (EPM) Copolymers, Poster Presentation, ISPAC-10, 10th International Symposium on Polymer Analysis and Characterisation, University of Toronto, Toronto, Canada, 1997. 

X-ray fluorescence emission (8, 9) atomic absorption (10-12), Mossbauer (13), and scanning Auger (14) spectroscopic methods and neutron activation analysis (NAA) (15-17). In addition, several exotic physical methods such as X-ray xeroradiography (18, 19) and photoacoustic analysis (20) have been applied to the study of ceramics. Of the analytical methods listed, neutron activation has been the most frequently used technique. 

A high resolution study of the Vj band of HCN at 3 )un has been recently reported using a standard small volume cell of non-resonant design . The 25 lowest rotational levels of the V3 band were excited with a tunable < lor center laser at an HCN pressure of 20 m Torr. The pressure of the N2 buffer gas was varied between 20 and 400 Torr to investigate pressure broadening and to detect possible frequency shifts induced by the buffer gas. In intracavity experiments performed at an HCN pressure of only 0,02 mTorr no shift of the transition frequency could be detected, to the accuracy of the wavemeter readout. The results of this photoacoustic analysis of the V3 band of HCN are ... 

S. Scheme of a dilution tube system and a resonant photoacoustic cell for the investigation of exhaust partioilate the filter collection was used for chemical and mass analysis the sampling rate for the photoacoustic analysis was 1,5 1/min... 

Rohlfing, A., Menzel, C., Kukreja, LM., Hillenkamp, F., and Dreisewerd, K. (2003) Photoacoustic analysis of matrix-assisted laser desorption/ ionization processes with pulsed infrared lasers. J. Phys. Chem. B, 107, 12275-12285. 

Photoacoustic analysis for identification of cured or insoluble materials such as composite materials, thermoplastic parts and inorganic fillers... 

Siebert D R, West G A and Barrett J J 1980 Gaseous trace analysis using pulsed photoacoustic Raman spectroscopy Appl. Opt. 19 53-60... 

Only slightly less accurate ( 0.3—0.5%) and more versatile in scale are other titration techniques. Plutonium maybe oxidized in aqueous solution to PuO " 2 using AgO, and then reduced to Pu" " by a known excess of Fe", which is back-titrated with Ce" ". Pu" " may be titrated complexometricaHy with EDTA and a colorimetric indicator such as Arsenazo(I), even in the presence of a large excess of UO " 2- Solution spectrophotometry (Figs. 4 and 5) can be utilized if the plutonium oxidation state is known or controlled. The spectrophotometric method is very sensitive if a colored complex such as Arsenazo(III) is used. Analytically usehil absorption maxima and molar absorption coefficients ( s) are given in Table 10. Laser photoacoustic spectroscopy has been developed for both elemental analysis and speciation (oxidation state) at concentrations of lO " — 10 M (118). Chemical extraction can also be used to enhance this technique. 

The scanning transmission electron microscope (STEM) was used to directly observe nm size crystallites of supported platinum, palladium and first row transition metals. The objective of these studies was to determine the uniformity of size and mass of these crystallites and when feasible structural features. STEM analysis and temperature programmed desorption (TPD) of hydrogen Indicate that the 2 nm platinum crystallites supported on alumina are uniform In size and mass while platinum crystallites 3 to 4 nm in size vary by a factor of three-fold In mass. Analysis by STEM of platinum-palladium dn alumina established the segregation of platinum and palladium for the majority of crystallites analyzed even after exposure to elevated temperatures. Direct observation of nickel, cobalt, or iron crystallites on alumina was very difficult, however, the use of direct elemental analysis of 4-6 nm areas and real time Imaging capabilities of up to 20 Mx enabled direct analyses of these transition metals to be made. Additional analyses by TPD of hydrogen and photoacoustic spectroscopy (PAS) were made to support the STEM observations. 

Concrete applications of micro reactors for chemical analysis, albeit so far not a core application, have been described [5]. Among other uses in chemical analysis, micro devices for gas chromatography, infrared spectroscopy, and photoacoustic detection are mentioned. 

Table 5.5 shows the main characteristics of UV spectrophotometry as applied to polymer/additive analysis. Growing interest in automatic sample processing looks upon spectrophotometry as a convenient detection technique due to the relatively low cost of the equipment and easy and cheap maintenance. The main advantage of UV/VIS spectroscopy is its extreme sensitivity, which permits typical absorption detection limits in solution of 10-5 M (conventional transmission) to 10 7 M (photoacoustic). The use of low concentrations of substrates gives relatively ideal solutions [20]. As UV/VIS spectra of analytes in solution show little fine structure, the technique is of relatively low diagnostic value on the other hand, it is one of the most widely used for quantitative analysis. Absorption of UV/VIS light is quantitatively highly accurate. The simple linear relationship between... 

Vol. 57 Photoacoustics and Photoacoustic Spectroscopy. By Allan Rosencwaig Vol. 58 Analysis of Pesticide Residues. Edited by H. Anson Moye Vol. 59 Afflty Chromatography. By William H. Scouten... 

Resonant photoacoustic gas spectrometry was adapted to fiber optic sensor technology32 as early as in 1984. A Mach-Zehnder arrangement was combined with a resonant photoacoustic cell for gap analysis. The pollutant gas NO2 was detectable in a concentration of 0.5 ppm. In a smart optical fiber hydrogen sensor, the fiber is coated with palladium metal which expands on exposure to hydrogen. This changes the effective optical path length of the fiber, which is detected by interferometry33. 

Handbook of Petroleum Analysis. By James G. Speight Handbook of Petroleum Product Analysis. By James G. Speight Photoacoustic Infrared Spectroscopy. By Kirk H. Michaelian... 

J. Rudzki Small, L. J. Libertini, E. W. Small. Analysis of Photoacoustic Waveforms Using the Nonlinear Least Squares Method. Biophys. Chem. 1992, 42, 29—48. 

Thompson, S. E., Foster, N. S., Johnson, T. J., Valentine, N. B., and Amonette, J. E. (2003). Identification of bacterial spores using statistical analysis of Fourier transform infrared photoacoustic spectroscopy data. Appl. Spectrosc. 57, 893-899. 

Depth-Profiling by Phase Analysis of Photoacoustic X-ray Absorption Spectroscopy... 

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