CO, propylene, and propane are common components in automotive exhaust. These pollutants are converted to CO$\sb2$ and H$\sb2$O by three-way catalysts contained in the catalytic converter of your automobile. These catalysts (Pt, Rh, CeO$\sb2$) are very effective in converting the pollutants under varying exhaust conditions; however, the method by which these catalysts achieve their high activity is not fully understood. The activities and kinetics for the oxidation of carbon monoxide, propylene, and propane oxidations were compared over Pt/Al$\rm\sb2O\sb3$ and Pt/CeO$\rm\sb2/Al\sb2O\sb3$ catalysts in an attempt to correlate catalyst activity with the chemistry of the reactants. Additional experiments involving CO, H$\sb2$ and O$\sb2$ chemisorption, the extent of reduction and oxidation of CeO$\sb2$ and CeO$\rm\sb2/Al\sb2O\sb3$, spillover studies, and the activity of Pt/Nd$\rm\sb2O\sb3/Al\sb2$O catalysts were performed in order to correlate catalyst activity with the strength of adsorption of the reactants and the mobility of lattice oxygen in CeO$\sb2$. Experiments were also performed for methanol oxidation over Pt/Al$\rm\sb2O\sb3$, Pt/CeO$\rm\sb2/Al\sb2O\sb3$, and Pt/K$\rm\sb2O/Al\sb2O\sb3$ catalysts in order to further understand the effects of ceria on the complete oxidation of alternate fuels. The Pt/CeO$\rm\sb2/Al\sb2O\sb3$ catalyst was more active than the PT/Al$\rm\sb2O\sb3$ catalyst for CO and propylene oxidation but less active for propane oxidation. It appears that an Eley-Rideal mechanism whereby gaseous oxygen reacts with CO adsorbed on Pt is consistent with the kinetic results for CO oxidation on Pt/Al$\rm\sb2O\sb3$. Based on the kinetic results and studies reported in the literature, it was suggested that CO and propylene adsorbed on Pt reacted with adsorbed oxygen species (O$\sb2\sp-$ and O$\sp-$) at low temperatures ($<$170$\sp\circ$C) and lattice oxide ions (O$\sp{-2}$) at higher temperatures ($>$200$\sp\circ$C) over Pt/CeO$\rm\sb2/Al\sb2O\sb3$ catalysts. The adsorption experiments showed that CO adsorbed only on the Pt sites, whereas O$\sb2$ adsorption was enhanced on the ceria phase of a Pt/CeO$\rm\sb2/Al\sb2O\sb3$ catalyst. Therefore, a Pt/CeO$\rm\sb2/Al\sb2O\sb3$ catalyst can accommodate a large amount of CO and O$\sb2$. On the other hand, it was shown by the activity and kinetic results that oxygen inhibited the adsorption of propane on Pt sites thereby rendering the Pt/CeO$\rm\sb2/Al\sb2O\sb3$ catalyst less effective for propane oxidation. The presence of ceria reduced the partial oxidation product, CO, for both propylene and propane oxidations. The additional experiments suggest that H$\sb2$ and CO adsorbed only on the Pt sites, O$\sb2$ adsorption is enhanced on Pt/CeO$\rm\sb2/Al\sb2O\sb3$ catalysts, Ce$\rm\sb2O\sb3$ and Ce$\rm\sb2O\sb3/Al\sb2O\sb3$ were not produced by H$\sb2$ reduction at 800$\sp\circ$C, Pt/Nd$\rm\sb2O\sb3/Al\sb2O\sb3$ was more active than Pt/Al$\rm\sb2O\sb3$, and H$\sb2$ spillover with Pt present may be responsible for the activation of ceria. The Pt/Al$\rm\sb2O\sb3$ and Al$\rm\sb2O\sb3$ catalysts produced dimethyl ether as the main reaction product for methanol oxidation. However, the dimethyl ether yield was reduced over Pt/CeO$\rm\sb2/Al\sb2O\sb3$ and Pt/K$\rm\sb2O/Al\sb2O\sb3$ catalysts.

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In 1844 Charles Goodyear obtained U.S. Patent #3,633 for his “Gum Elastic Composition”. In a published circular, which describes his patent for the sulfur vulcanization of gum elastic composition, he stated: “No degree of heat, without blaze, can melt it (rubber)… It resists the most powerful chemical reagents. Aquafortis (nitric acid), sulphuric acid, essential and common oils, turpentine and other solvents… …” Goodyear's sulfur vulcanization of rubber fueled much of the industrial revolution and made transportation possible, as it exists today. In doing so, Goodyear created one of the most difficult materials to recycle. Rubber will not melt, dissolve, or lend itself to the usual methods of chemical decomposition. Ironically, Goodyear recognized this problem and in 1853 he patented the process of adding ground rubber to virgin material, now currently known as regrind blending. Today, scrap tires represent one of the most serious sources of pollution in the world. Studies estimate that there are roughly 2 billion scrap tires in U.S. landfills and more are being added at a rate of over 273 million tires per year. Current methods of recycling waste tires are crude, ineffective, and use rubber powder as a low cost filler instead of a new rubber. The groundwork for a very simple and effective method of producing high-quality rubber goods using 100% scrap rubber was discovered in 1944 by A. V. Tobolsky et al. This application, however, was not recognized until recently in our laboratory. The process as studied to date represents a method of creating quality, high-value added rubber goods with nothing other than heat and pressure. High pressure is required to obtain a void-free compaction of the rubber particles by forcing all of the free surfaces into intimate contact. High temperature then activates the chemical rearrangement, scission, and reformation of the chemical bonds thus providing new bridges between the once fractured interfaces. This occurs both within and between particles. The technique of high-pressure high-temperature sintering has worked on all types of thermoset materials. Typical mechanical properties for sintered SBR powder rubber are as follows: 1.3 MPa 100% Modulus, 12.0 MPa Tensile Strength and 300% Elongation at Break. The goal of this research is two-fold. First, to gain an understanding of the variables that control the process of high-pressure high-temperature sintering. Second, to study the factors governing the mechanism of fusion with the hope of controlling and exploiting this process so that tires can be recycled to produce high quality and high-value added products.

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This thesis provides a bridge between analytical modeling and neural network modeling. Two different approaches have been explored. Both approaches rely on embedding radial basis function (RBF) modules in the approximate model of the plant so that they can be trained to compensate for modeling uncertainty. One approach has led to the development of a model-based recurrent neural network (MBRNN) for modeling nonlinear dynamic systems. The RBF modules take the form of activation functions in the MBRNN network, that is formu1ulated according to a linearized state-space model of the plant. This network is trained to represent the process nonlinearities through modifying the activation functions of its nodes, while keeping the original topology of the neural network intact. The performance of the MBRNN is demonstrated via several examples. The results indicate that it requires much shorter training than needed by ordinary recurrent networks. The utility of the MBRNN is tested in fault diagnosis of the IFAC Benchmark Problem and its performance is compared with ‘black box’ neural solutions. The results indicate that the MBRNN provides better results than ‘black box’ neural networks, and that with training it improves the results from other model-based residual generators. The second approach incorporates RBF modules in the nonlinear estimation model to enhance the performance of the extended Kalman filter (EKF) in coping with the uncertainty of this model. In this method, single-input single-output radial basis function (RBF) modules are embedded within the nonlinear estimation model to provide additional degrees of freedom for model adaptation. The weights of the embedded RBF modules are. adapted by the EKF concurrent with state estimation. This modeling compensation method is tested in application to an induction motor benchmark problem. Simulation results indicate that the RBF modules provide the means to model the uncertain components of the estimation model within their range of variation. The utility of the embedded RBF-based nonlinear adaptive observer was tested in fault diagnosis of a throttle sensor fault in an internal combustion engine. The test results show that this observer enhances the residuals obtained for fault diagnosis.

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There is no international regulation for the frontal collision of the buses, protecting their occupants and partners in traffic. There are some regulation such as ECE R-80 which deals with strength of seat structure of the coaches and their anchorages strength. There is increasing need to focus issues like occupant protection and full scale crash testing regulation for buses. This thesis attempts to collect possible subjects required for international regulation required for crashworthiness of transit buses. This research attempts to develop and validate a model of transit bus for all three impact conditions. The full finite element model is developed with help hypermesh software and its validation and analysis is done with help Ls-Dyna nonlinear finite element solver. The cost of actual testing and secrecy maintained by manufacturers make research process difficult and increase the importance of computer simulations. To boost the research of crash worthiness of transit need for computer model is felt. This thesis examines several frontal crash test procedures and evaluates how well each procedure meets the objective. This validated model is used to analyze various real world impact scenarios and its analysis with European and federal regulation. This validated model is used to extract crash pulses of various impact scenarios at the center of gravity of the bus. These extracted crash pulses are applied to the madymo model to estimate the injuries to occupants of the bus. This thesis discusses the design aspects of bus frontal impact behavior as one of the main subjects of bus crashworthiness and results of previous full scale tests comparing the Fem simulation results carried out on the transit bus. / Thesis (M.S.)--Wichita State University, College of Engineering, Dept. of Mechanical Engineering / "December 2006."

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