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Showing 1 to 20 of 130 for “"thermal degradation"”.
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Thermal degradation of organophosphorus compounds.
… the separation and isolation of the products of thermal degradation. Infrared, ultraviolet, 1H nuclear magnetic resonance and mass spectra of the isolated compounds are recorded and evaluated. Structures are proposed for the isolated compounds and the spectroscopic properties of authentic samples …
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The thermal degradation of polystyrene.
A review is made of the thermal degradation of polystyrene. In a theoretical study the importance of intramolecular transfer during degradation is emphasized in the formation of oligomeric volatiles. To account for past experimental results a mechanism is proposed involving biradical cage …
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Thermal Degradation Studies of Polycarbonate
… Frequently, these demanding conditions result in degradation of the polymer and subsequent decreases in desirable properties. Clearly then, a methodology to predict important properties, such as Tg, molecular weight, and tensile strength, from knowledge of the environmental history of a …
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Thermal Degradation of PC and PA6 During Laser Transmission Welding (LTW)
… of LTW starts to decline due to material thermal degradation. Thermal degradation of materials is a kinetic phenomenon which depends on both temperature and time. Therefore there is no specific temperature for thermal degradation. Thermal gravimetric analysis (TGA) is used to study the …
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Accelerated thermal degradation testing of GAN HEMTs under high-temperature stress
… advantages, GaN HEMTs are prone to performance degradation when exposed to elevated temperatures and electrical stress over long durations. This study aims to investigate the degradation behavior of commercial EPC90122 GaN HEMT devices under controlled high-temperature operating conditions. …
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A study of the thermal degradation of flexible tdi-based polyurethane foams
… research project was, therefore, to study the degradation behaviour of toluene diisocyanate (TDI)-based polyurethane foams in order to determine the mechanisms which occur and the effect that various fire retardants have on the degradation mechanisms. The results have demonstrated that the …
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Structural Investigation On The Thermal Degradation Of Aqueous Amines In Post-Combustion Co2 Capture
… with aqueous amines, is their ability to thermally degrade. Thermal degradation is a prominent aspect for the loss of aqueous amines during the stripper process in powerplants. The focus of this research was to investigate the structural effect on the thermal degradation of aqueous amines. …
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A study of the thermal degradation of model compounds of amine-cured epoxide resins
[page 49 missing] The thermal ciegradation of rr..odel compounds of a~ine-cur2d epoxide resins has been studied with the aim of investigating the thermal stability of the "cure-linkage". · 1, 3-Diphenoxypropan-2 ~ol and l-(N-ethylanilino)-3-phenoxypropan-2-ol have been synthesised and degraded m~er …
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Gas-Phase Formation of Environmentally Persistent Free Radicals from Thermal Degradation of Catechol, Hydroquinone, Phenols and Tobacco
… Consequently, we have performed studies of the thermal degradation of catechol, hydroquinone and phenol and structurally similar derivatives that have been proposed as progenitors of semiquinone type radicals. Tobacco pyrolysis has also been investigated. We have employed in conjunction with the …
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Part I: In-situ fluorometric quantification of microalgal neutral lipids Part II: Thermal degradation behavior of investment casting polymer patterns
… Density, elastic modulus, expansion coefficient, thermal degradation behavior, etc. were experimentally investigated for their effects on metal casting quality. The reduction in toxic hydrogen cyanide (HCN) generated during thermal decomposition of polyurethane pattern was achieved by increasing …
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Iron (III) Oxide and Copper (II) Oxide Mediated Formation of PCDD/Fs from Thermal Degradation of 2-MCP and 1,2-DCBz
… (PCDD/Fs) which occurs inexorably from most thermal and combustion processes constitutes a major toxic component of environmental pollutants. Generally, it is well established that transition metal-mediated reactions account for the majority of PCDD/F emissions from combustion sources. …
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Molecular Products from the Thermal Degradation of Selected Tobacco Components: Lignin, Tyrosine, Glutamic Acid, and Modeling of Lignin Pyrolysis using CHEMKIN Combustion Suite
This study explores the thermal decomposition behavior of selected tobacco components: lignin, tyrosine, and glutamic acid using the system for thermal diagnostic studies (STDS) in an in-line gas chromatography-mass spectrometer analytical technique. The pyrolysis conditions employed in this study …
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Chain Extension of Polyamide-6 & Polyamide-6/Organoclay Nanocomposites. Control of thermal degradation of polyamide-6/organoclay nanocomposites during extrusion using a novel chain extender
Novel solutions to offset thermal degradation of polyamide-6 (PA-6) and organoclay (organically modified layered silicates) nanocomposites during melt compounding have been investigated. In this research, a novel chain extender (Joncryl ADR 3400) has been used to improve thermal stability of PA-6 …
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The Development and Evaluation of Novel Techniques for the Study of Polymerisation and Degradation Reactions
… incorporating some novel features, for use in thermal degradation studies of polymers. The technique combines thermo-gravimetric, gas evolution and gas liquid chromatographic analyses, the latter being coupled to in-line filament and Curie point pyrolysis techniques. A further technique is …
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Transmission Electron Microscopy (Tem) Study of Minerals in Coal
… cooled by liquid nitrogen was used to reduce thermal degradation of the minerals by the ion-beam.
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Effects of elevated temperature exposure on cement-based composite materials
… are considered to have higher degree of thermal and fire resistance than steel structures due to their non-combustible nature and low thermal conductivity. Despite concrete structures having high degree of thermal resistance, there is loss in mechanical properties and durability when they …
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Mechanical Properties and Durability of Natural Rubber Compounds and Composites
… this research was to investigate the effect of thermal degradation upon the mechanical properties of natural rubber compounds and apply those effects to the life prediction of off axis 2-ply cord rubber laminates. The work examined both the quasi-static and dynamic mechanical properties of two …
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InP/InGaAs Heterojunction Bipolar Transistors and Field-Effect Transistors Grown by Gas -Source Molecular Beam Epitaxy
Finally, the thermal degradation of heavily C-doped InGaAs and its effects on dc properties of InGaAs/InP HBTs have been studied. The degradation of the junction properties and current gain-base sheet resistance ratio can be attributed to the formation of C precipitates. These findings are …
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Radiation induced degradation of elastomers.
… has been made to evaluate the kinetics of the thermal and combined thermal/radiative degradation of a peroxide cured polydimethylsiloxane elastomer (PDMS), and a vinylidene fluoride-hexafluoropropylene elastomer (Viton E60-C),by chemical stress relaxation measurements. It was observed that the …
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