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de la Vaissiere C Luth V Abrams GS Amidei D Baden AR Barklow T Boyarski AM Boyer J Breidenbach M Burchat P Burke DL Butler F Dillon JW Dorfan JM Feldman GJ Gidal G Gladney L Gold MS Goldhaber G Golding LG Hanson G Haggerty J Herrup D Himel T Hollebeek RJ Innes WR Jaros JA Juricic I Kadyk JA Klein SR Lankford AJ Larsen RR LeClaire BW Levi ME Lockyer NS Matteuzzi C Nelson ME Ong RA Perl ML Richter B Ross MC Rowson PC Schaad T Schellman H Schmidke WB Sheldon PD Trilling GH Yelton JM Wood DR 《Physical review letters》1985,54(19):2071-2074
33.
Mutagenic primary polycyclic aromatic amines present in shale oil and synthetic crudes may be readily detected by a simple derivatization and Chromatographic procedure. Nitrogenous bases and amines are extracted from the sample with dilute mineral acid and derivatized with trifluoroacetic anhydride. The derivatized amines are separated by gas chromatography and specifically detected using a glow-discharge detector tuned to an emission wavelength of fluorine. Under these conditions, the aromatic nitrogenous bases, such as acridine, are not detected even though they are present in the sample. As little as 14 ng of fluorine, arising from the derivative of 33 ng of 2,4,6-trimethylaniline, can be detected. The selectivity of the glow-discharge detector for derivatized amines vs. nonderivatized aromatic nitrogenous bases was estimated to be a minimum of 200:1. 相似文献
34.
Tanskanen H Khriachtchev L Räsänen M Feldman VI Sukhov FF Orlov AY Tyurin DA 《The Journal of chemical physics》2005,123(6):64318
Vinyl radicals produced by annealing-induced reaction of mobilized hydrogen atoms with acetylene molecules in solid noble-gas matrices (Ar, Kr, and Xe) were characterized by Fourier transform infrared and electron paramagnetic resonance (EPR) spectroscopies. The hydrogen atoms were generated from acetylene by UV photolysis or fast electron irradiation. Two vibrational modes of the vinyl radical (nu7 and nu5) were assigned in IR absorption studies. The assignment is based on data for various isotopic substitutions (D and 13C) and confirmed by comparison with the EPR measurements and density-functional theory calculations. The data on the nu7 mode is in agreement with previous experimental and theoretical results whereas the nu5 frequency agrees well with the computational data but conflicts with the gas-phase IR emission results. 相似文献
35.
Frey GL Reynolds KJ Friend RH Cohen H Feldman Y 《Journal of the American Chemical Society》2003,125(19):5998-6007
The development of low-cost, large-area electronic applications requires the deposition of active materials in simple and inexpensive techniques at room temperature, properties usually associated with polymer films. In this study, we demonstrate the integration of solution-processed inorganic films in light-emitting diodes. The layered transition metal dichalcogenide (LTMDC) films are deposited through Li intercalation and exfoliation in aqueous solution and partially oxidized in an oxygen plasma generator. The chemical composition and thickness of the LTMDC and corresponding transition metal oxide (TMO) films are investigated by X-ray photoelectron spectroscopy. The morphology and topography of the films are studied by atomic force microscopy. X-ray powder diffraction is used to determine the orientation of the LTMDC film. Finally, the LTMDC and their corresponding oxides are utilized as hole-injecting and electron-blocking materials in polymer light-emitting diodes with the general structure ITO/LTMDC/TMO/polyfluorene/Ca/Al. Efficient hole injection and electron blocking by the inorganic layers result in outstanding device performance and high efficiency. 相似文献
36.
A helium glow discharge is employed as a gas Chromatographie detector which is selective for silicon. Operated with spectral background compensation at 251.6 nm or 288.2 nm, the detector shows a lower limit of detection of 5 ng of silicon per injection. The detector is applied to the rapid screening of trimethylsilylated fractions of shale-derived liquids being prepared for biossay. 相似文献
37.
D. Feldman M. Chervenka E. Stokh M. Shimanska E. Khaber 《Chemistry of Heterocyclic Compounds》1995,31(1):80-85
Methyl derivatives of several nitrogen-containing heterocyclic compounds were converted into the corresponding carboxylic acids by means of electrochemical oxidation at the nickel oxohydroxide anode in alkaline medium, using a nondiaphragm electrolyzer. The oxidation of 2,5-dimethylpyrazine was used to demonstrate the effect of adding chromium (III) and cobalt (II) compounds to the reaction mixture. The composition and electronics state of the anode surface were studied usign x-ray diffraction and XPS methods. 相似文献
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Schumm BA Koetke DS Adolphsen CE Alexander JP Averill D Barish BC Barklow T Barnett BA Blockus D Boyarski A Brabson B Breakstone A Bulos F Burchat PR Burke DL Cence RJ Chapman J Chmeissani M Cords D Coupal DP Dauncey P DeStaebler HC Dorfan JM Drell PS Drewer DC Durrett D Elia R Feldman GJ Field RC Ford WT Fordham C Frey R Fujino D Gan KK Gero E Gidal G Glanzman T Goldhaber G Gomez Cadenas JJ Gratta G Hanson G Harr R Harral B Harris FA Hayes K Hearty C Heusch CA Hildreth MD Himel T Hinshaw DA 《Physical review D: Particles and fields》1992,46(1):453-456