Download or read book Thermal Decomposition of Molecules Relevant to Combustion and Chemical Vapor Deposition by Flash Pyrolysis Time of flight Mass Spectrometry written by Jessy Mario Lemieux and published by . This book was released on 2013 with total page 207 pages. Available in PDF, EPUB and Kindle. Book excerpt: Flash pyrolysis coupled with vacuum-ultraviolet photoionization time-of-flight mass spectrometry was used to study the thermal decomposition mechanisms of molecules relevant to fuel combustion and the chemical vapor deposition (CVD) of SiGe, SiC, and GeC. For combustion research, the thermal decomposition of benzyl radical, n-alkanes C n H2n+2 (n = 5-8 and 10), 1-butyl radical, and 1-pentyl radical was performed. Benzyl was confirmed to decompose primarily by ejection of H atom after significant isomerization with loss of methyl observed as a minor decomposition pathway. Thermal decomposition of n-alkanes by C-C bond homolysis was directly observed with preferential fission of central C-C bonds. Methyl radical formation by homolysis of the [Alpha] C-C bond was observed to be the least significant C-C bond homolysis pathway. Decomposition of 1-butyl by [Beta]-scission to form ethene and ethyl radical was directly observed. Significant isomerization of 1-pentyl radicals by 1,4-H migration followed by [Beta]-scission was observed at temperatures below 900 K with direct [Beta]-scission of 1-pentyl becoming increasingly prevalent at higher temperatures. Gas phase CVD research included pyrolysis of SiH 4 /GeH4 mixture, tetramethylsilane, tetramethylgermane, and several methylchlorosilanes. Formation of highly unsaturated SiGeHz , Si2 GeHz , Si3 GeHz , SiGe2 H z , SiGe3 Hz and SiGe5 Hz clusters in the pyrolysis of a 1 to 1 SiH4 /GeH4 mixture by a silylene/germylene insertion mechanism was observed. The decomposition of tetramethylsilane and tetramethylgermane by Si-C bond homolysis was confirmed and newly observed secondary decomposition mechanisms were demonstrated. The decomposition of methyltrichlorosilane (MTS), an established SiC CVD precursor, was studied. Decomposition occurred primarily via Si-C bond homolysis at temperatures below 1350 K with elimination of CH 3 Cl to form SiCl2 becoming increasingly important as the pyrolysis temperature was increased. The mechanism of MTS decomposition was also compared to two other potential precursors, dimethyldichlorsilane and methyldichlorosilane.
Download or read book Pyrolysis of Organic Molecules Relevant to Combustion as Monitored by Photoionization Time of flight Mass Spectrometry written by Kevin Howard Weber and published by . This book was released on 2010 with total page 226 pages. Available in PDF, EPUB and Kindle. Book excerpt: Flash pyrolysis coupled to molecular beam extraction and single photon ionization time-of-flight mass spectrometry along with quantum chemical calculations are employed to study the pyrolysis of organic molecules with relevance to combustion processes. Branching ratios for the molecular elimination and bond fission pathways was achieved for ethyl and propyl iodides providing information about the nature of the mechanism with relation to chemical structure. Similarly, the decompositions of a series of alkyl methyl ethers, whose anti-knock ability in commercial fuels is attributed to the molecular elimination pathway, was investigated to examine the competition of primary and subsequent homolyses at higher temperatures, which tend to promote "knock". The isomerization/decomposition of isoprene was looked at in detail with special attention to the formation of soot precursor, most notably the "first ring" benzene. Cyclopentadiene and methylcyclopentadiene are known to be highly sooting fuels and were pyrolyzed to study the initial steps in aromatization. The pyrolysis of cyclohexene, cyclopentene, and 1,4-cyclohexadiene were conducted to facilitate interpretation of aromatic formation and to compare experimental results with well established mechanisms. Finally, the pyrolysis of methylcyclohexane, an important component some jet fuels, was studied.
Download or read book The Mechanisms of Pyrolysis Oxidation and Burning of Organic Materials written by Leo Aloysius Wall and published by . This book was released on 1972 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Molecular Beam Sampling Mass Spectrometry of High Heating Rate Pyrolysis Description of Data Acquisition System and Pyrolysis of HMX in a Polyurethane Binder written by Richard A. Beyer and published by . This book was released on 1978 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: The data acquisition capability of the time-of-flight mass spectrometer used with the molecular beam sampling system has been expanded. An oscilloscope intensity-modulated raster technique using negative film scanned by a microdensitometer provides simultaneous semi-quantitative time-resolved mass spectra of all masses up to 160 amu with time resolution down to 10 ms. A system of parallel sample/hold channels which follow predetermined masses with time resolution near that of the spectrometer cycle time has been assembled and shown to have good dynamic range, adequate mass resolution, and provide good reproducibility. This system has been used to study the products of low pressure pyrolysis of nitrocellulose and cyclotetramethylene tetranitramine/polyurethane binder. Using a carbon dioxide laser for heating the samples up to 5000 deg/s heating rate effects are clearly demonstrated for NC but are not observed for HMX/PU. Relative amounts of the major decomposition species observed for the HMX/PU were nitrous oxide, 100; nitrogen dioxide, 54; hydrogen cyanide, 42; formaldehyde, 39; and nitric oxide, 27. The large amounts of nitrogen dioxide is compatible with the breaking of the N-N bond as the first step of the thermal decomposition of HMX. (Author).
Download or read book Dissertation Abstracts International written by and published by . This book was released on 2002 with total page 734 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Quantitative Measurement of Pyrolysis and Combustion Species Concentration by Molecular beam sampling mass spectrometry written by Xian Zhong and published by . This book was released on 1992 with total page 220 pages. Available in PDF, EPUB and Kindle. Book excerpt: A molecular-beam-sampling apparatus utilizing both a time-of-flight mass spectrometer with vacuum ultraviolet (VUV) photoionization and a quadrupole mass spectrometer with electron impact ionization is described. These systems are used to analyze reactants and products, as well as reactive intermediates, from flow tube experiments at reduced pressures and elevated temperatures. It is shown that the quadrupole signal sensitivity can be predicted using literature cross sections which are based upon the atom hybridization within the various molecules. Measurements of the VUV photoionization sensitivity for stable species led to development of a group additivity approach to predict cross sections. This approach was extended to reactive intermediates, and detailed comparisons of quadrupole and TOF data shows a very good agreement between the two techniques. The two techniques are compensation of each other and provide the full information we need. It is also shown how the minimal fragmentation achieved with the VUV source leads to much more accurate species concentration measurements for reactive intermediates.
Download or read book Pyrolysis Mass Spectrometry of Recent and Fossil Biomaterials written by H.L.C. Meuzelaar and published by Elsevier. This book was released on 2000-04-01 with total page 309 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pyrolysis Mass Spectrometry of Recent and Fossil Biomaterials
Download or read book Chemical Physics of Pyrolysis Combustion and Oxidation written by Al. Al Berlin and published by Nova Publishers. This book was released on 2005 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: Chemical Physics of Pyrolysis, Combustion & Oxidation
Download or read book Pyrolysis gas Chromatography Mass Spectrometry Of Polymeric Materials written by Peter Kusch and published by World Scientific. This book was released on 2018-10-08 with total page 268 pages. Available in PDF, EPUB and Kindle. Book excerpt: The methodology of analytical pyrolysis-GC/MS has been known for several years, but is seldom used in research laboratories and process control in the chemical industry. This is due to the relative difficulty of interpreting the identified pyrolysis products as well as the variety of them. This book contains full identification of several classes of polymers/copolymers and biopolymers that can be very helpful to the user. In addition, the practical applications can encourage analytical chemists and engineers to use the techniques explored in this volume.The structure and the functions of various types of pyrolyzers and the results of the pyrolysis-gas chromatographic-mass spectrometric identification of synthetic polymers/copolymers and biopolymers at 700°C are described. Practical applications of these techniques are also included, detailing the analysis of microplastics, failure analysis in the automotive industry and solutions for technological problems.
Download or read book Thermal Decomposition of Charring Materials written by Said Nurbakhsh and published by . This book was released on 1989 with total page 552 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book GAP Decomposition and Combustion Chemistry Studied by Molecular Beam Mass spectrometry written by Oleg P. Korobeinichev and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1994 with total page 892 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Microprobe and Molecular beam Mass Spectrometry in Plasma enhanced Chemical Vapor Deposition written by Roberto A. Pugliese and published by . This book was released on 1993 with total page 380 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Molecular Beam Mass Spectrometry Measurement of 1 butene Pyrolysis and Combustion Products written by Xian Zhong and published by . This book was released on 1998 with total page 878 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Products of Flash Pyrolysis of Phenol Formaldehyde by Time of Flight Mass Spectroscopy written by Henry L. Friedman and published by . This book was released on 1962 with total page 33 pages. Available in PDF, EPUB and Kindle. Book excerpt: A sample of phenol-formaldehyde was flash pyrolized eleven times in the reaction chamber of a time-of-flight mass spectrometer. Quantitative analyses were determined for pyrolysis products which were present within ten seconds after each flash. A high degree of consistency between compositions of products from consecutive flashes resulted. A discussion of the results is presented. (Author-PL).
Download or read book Soot Formation in Combustion written by Henning Bockhorn and published by Springer Science & Business Media. This book was released on 2013-03-08 with total page 595 pages. Available in PDF, EPUB and Kindle. Book excerpt: Soot Formation in Combustion represents an up-to-date overview. The contributions trace back to the 1991 Heidelberg symposium entitled "Mechanism and Models of Soot Formation" and have all been reedited by Prof. Bockhorn in close contact with the original authors. The book gives an easy introduction to the field for newcomers, and provides detailed treatments for the specialists. The following list of contents illustrates the topics under review:
Download or read book Pyrolysis Molecular Weight Chromatography Vapor Phase Infrared Spectrophotometry An On Line System for Analysis of Polymers III Thermal Decomposition of Polysulfones and Polystyrene written by Erdogan Kiran and published by . This book was released on 1976 with total page 31 pages. Available in PDF, EPUB and Kindle. Book excerpt: A new experimental system for investigation of the volatile products of thermal degradation has been applied to polysulfones and polystrene. (Author).
