Reactions in the solid state
- Authors: Brown, Michael Ewart
- Date: 2006
- Subjects: Solid state chemistry , Thermal analysis , Chemistry, Analytic
- Language: English
- Type: Thesis , Doctoral , DSc
- Identifier: vital:4529 , http://hdl.handle.net/10962/d1015762
- Description: I have chosen the title for this thesis, "Reactions in the Solid State", for two reasons: Firstly, it is broad enough to cover all of my areas of research, which have been: • Effects of irradiation on solids (PhD topic) • Silver refining (while at the Chamber of Mines) • Kinetics of decomposition of solids (with Dr A.K. Galwey and various others) • Techniques of thermal analysis • Pyrotechnic delay systems (with support from AECI Explosives) • Thermal and photostability of drugs (with Prof B.D. Glass) and, secondly, it was the title of the very successful book co-authored by Drs Andrew Galwey, David Dollimore and me. A large part of my research has been involved in the writing and editing of books, so these are covered in a separate commentary, while commentary on the more than 100 papers to which I have contributed forms the main part of this compilation. It is hoped that the electronic format will enable ready access of to all aspects of my research, including electronic versions of the original papers. The reader will need a copy of Adobe Acrobat Reader to access these.
- Full Text:
- Date Issued: 2006
- Authors: Brown, Michael Ewart
- Date: 2006
- Subjects: Solid state chemistry , Thermal analysis , Chemistry, Analytic
- Language: English
- Type: Thesis , Doctoral , DSc
- Identifier: vital:4529 , http://hdl.handle.net/10962/d1015762
- Description: I have chosen the title for this thesis, "Reactions in the Solid State", for two reasons: Firstly, it is broad enough to cover all of my areas of research, which have been: • Effects of irradiation on solids (PhD topic) • Silver refining (while at the Chamber of Mines) • Kinetics of decomposition of solids (with Dr A.K. Galwey and various others) • Techniques of thermal analysis • Pyrotechnic delay systems (with support from AECI Explosives) • Thermal and photostability of drugs (with Prof B.D. Glass) and, secondly, it was the title of the very successful book co-authored by Drs Andrew Galwey, David Dollimore and me. A large part of my research has been involved in the writing and editing of books, so these are covered in a separate commentary, while commentary on the more than 100 papers to which I have contributed forms the main part of this compilation. It is hoped that the electronic format will enable ready access of to all aspects of my research, including electronic versions of the original papers. The reader will need a copy of Adobe Acrobat Reader to access these.
- Full Text:
- Date Issued: 2006
Intersolid pyrotechnic reactions of silicon
- Authors: Rugunanan, Rajan Anil
- Date: 1992
- Subjects: Thermochemistry , Thermal analysis , Chemistry, Analytic , Chemistry, Organic , Silicon
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4527 , http://hdl.handle.net/10962/d1015571
- Description: A study of the role of different oxidants with silicon as the fuel in simple binary pyrotechnic compositions is reported. Several oxidants were examined, but only three (Sb₂0₃, Fe₂0₃ and Sn0₂) satisfied the restrictions that the combustion temperatures should be below the melting point of platinum/rhodium thermocouples (1760°C), that burning rates should not exceed the response of the thermocouples, and that burning should occur without significant mass-transport. A fourth oxidant, KN0₃, was selected on account of its low melting point and general importance as a pyrotechnic oxidant. The oxidation of silicon in the presence of either Sb₂0₃ or KN0₃ could be identified from thermal analysis curves. No thermal events were noted when Si/Sn0₂ and SiFe₂0₃ compositions were heated under similar conditions. The oxidation of Si powder in oxygen was also studied. All four binary systems sustained burning over a reasonably wide range of compositions. The range of burning rates measured (2 to 35 mm s⁻¹) depended on the oxidant used. Fe₂0₃ and Sb₂0₃ gave slow burning mixtures compared to Sn0₂ and to KN0₃ compositions with a high Si content. Burning rates generally increased with increasing specific surface area of silicon, but decreased in the presence of inert diluents and moisture. The burning rates of the Si/Fe₂0₃ and Si/Sn0₂ systems increased with increasing compaction of the samples. Kinetic parameters derived from the temperature proftles recorded during combustion were generally low (6 to 37 kJ mol⁻¹). This is in keeping with proposals that burning is diffusion controlled. The values of kinetic parameters derived from thermal analysis curves were considerably greater ( > 250 kJ mol⁻¹). Two other fuels, FeSi₇ and CaSi₂, gave similar thermal analysis curves when used instead of silicon. There were considerable differences in the burning rates for binary mixtures of these fuels compared to silicon. Ternary systems with two fuels or two oxidants showed that only limited interaction occurs during thermal analysis. The use of a second fuel or oxidant did, however, modify the burning behaviour considerably. Other techniques used in this study to probe the details of the reaction processes included bomb calorimetry, measurement of thermal conductivities, infrared spectroscopy, X-ray diffraction and scanning electron micoscropy.
- Full Text:
- Date Issued: 1992
- Authors: Rugunanan, Rajan Anil
- Date: 1992
- Subjects: Thermochemistry , Thermal analysis , Chemistry, Analytic , Chemistry, Organic , Silicon
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4527 , http://hdl.handle.net/10962/d1015571
- Description: A study of the role of different oxidants with silicon as the fuel in simple binary pyrotechnic compositions is reported. Several oxidants were examined, but only three (Sb₂0₃, Fe₂0₃ and Sn0₂) satisfied the restrictions that the combustion temperatures should be below the melting point of platinum/rhodium thermocouples (1760°C), that burning rates should not exceed the response of the thermocouples, and that burning should occur without significant mass-transport. A fourth oxidant, KN0₃, was selected on account of its low melting point and general importance as a pyrotechnic oxidant. The oxidation of silicon in the presence of either Sb₂0₃ or KN0₃ could be identified from thermal analysis curves. No thermal events were noted when Si/Sn0₂ and SiFe₂0₃ compositions were heated under similar conditions. The oxidation of Si powder in oxygen was also studied. All four binary systems sustained burning over a reasonably wide range of compositions. The range of burning rates measured (2 to 35 mm s⁻¹) depended on the oxidant used. Fe₂0₃ and Sb₂0₃ gave slow burning mixtures compared to Sn0₂ and to KN0₃ compositions with a high Si content. Burning rates generally increased with increasing specific surface area of silicon, but decreased in the presence of inert diluents and moisture. The burning rates of the Si/Fe₂0₃ and Si/Sn0₂ systems increased with increasing compaction of the samples. Kinetic parameters derived from the temperature proftles recorded during combustion were generally low (6 to 37 kJ mol⁻¹). This is in keeping with proposals that burning is diffusion controlled. The values of kinetic parameters derived from thermal analysis curves were considerably greater ( > 250 kJ mol⁻¹). Two other fuels, FeSi₇ and CaSi₂, gave similar thermal analysis curves when used instead of silicon. There were considerable differences in the burning rates for binary mixtures of these fuels compared to silicon. Ternary systems with two fuels or two oxidants showed that only limited interaction occurs during thermal analysis. The use of a second fuel or oxidant did, however, modify the burning behaviour considerably. Other techniques used in this study to probe the details of the reaction processes included bomb calorimetry, measurement of thermal conductivities, infrared spectroscopy, X-ray diffraction and scanning electron micoscropy.
- Full Text:
- Date Issued: 1992
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