Spectra Gases

Caine ED, Polinsky RJ Haloperidol induced dysphoria in patients with Tourette syndrome. Am J Psychiatry 236 1216-1217, 1979 Caine ED, Weingartner H, Ludlow EA, et al Qualitative analysis of scopolamine-induced amnesia. Psychopharmacology 74 74-80, 1981 Calabrese JR, Delucchi GA Spectrum of efficacy of valproate in 55 rapid-cycling manic depressives. Am J Psychiatry 147 431-434, 1990 Calabrese JR, Markowitz PJ, Kimmel SE, et al Spectrum of efficacy of valproate in 78 rapid-cycling bipolar patients. J Clin Psychopharmacol 12 (suppl 53-56, 1992... 

The tetrahedral Ga spectrum (upper) is typical of gallium in framework sites. The additional octahedral Ga resonance (lower spectmm) arises from extra framework Ga generated during thermal treatment of the sample. From Occelli et al. (1999), by permission of Elsevier Science. 

FIGURE 6.8 Photoelectron spectrum of 20 produced by laser vaporization of graphite in helium gas (spectrum reproduced from Reference 37). Inset the totally symmetric tangential stretching mode of the acetylenic structure. 

The main advantage of MS/MS is its abihty to analyse specific target molecules directly from biological matrices without any sample preparation. One important application of MS/MS in food analysis can be the rapid screening of intact fruits or vegetables for the presence of mycotoxins or pesticides. For example intact lettuce leaves can be introduced directly into the ion source and analysed for the presence of the pesticide parathion. The CAD (methane gas) spectrum of this pesticide shows the parent ion at m/z 291 and two daughter ions at m/z 169 and m/z 154. If the peak at m/z 291 of the normal spectrum of the contaminated lettuce leaf is selected and its CAD spectrum is recorded and... 

In the p3/2 Ga spectrum of Fig. 7.3, an anomalous broadening of line 2(Ga) is observed, together with a rather sharp, but weak X feature near from the energy of the O(r) phonon in silicon. This feature is attributed to a splitting of line 2 due to the interaction with the O(r) phonon. This resonant interaction has been further studied under uniaxial stress by Chandrasekhar et al. [34]. The X feature is seen to be split by stress and its relative sharpness at zero stress is attributed to its interaction with phonons close to the q = 0 T point while line 2 interacts with a larger phonon distribution. 

Typical residual gas spectrum of a turbo-molecular pump. 

Selenium tetrafluoride is a colorless liquid (mp - 13.8° bp 106°). Since it is an excellent solvent, it is often yellow. It is hydrolyzed readily and attacks Pyrex glass at room temperature, especially if water is present. IR gas spectrum 733 (s), 622 (s), 361 (m) cm . 

Nippon Steel Chem. Osaka Gas Spectrum Quality Prods. 

Fig.2.10 Example of a spectrum taken with a CCL-spectrome-ter, using a computer controlled mode of operation. The various traces are from top to bottom. 1) reference gas spectrum. 2)first derivative of ionic species. 3) concentration modulated absorption signals. 4) Interpolation marks from etalon .

On examination of the gas residues in a spectroscope, indications of oxygen and nitrogen were of course found, but above all groups of red and green lines, never before observed in a gas spectrum. Sir William Crookes (1832-1919), professor at the Royal College of Chemistry and a pioneer in spectroscopy, was contacted in order to get a more extensive examination. He observed almost two hundred lines. Could that bear witness to a new element ... 

Fig. 7.2. Comparison of the methane spectmm upon electron ionization at different ion source pressures (a) approx. 10 Pa, (b) approx. 10 Pa. The latter represents the typical methane reagent gas spectrum in positive-ion CL...

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