• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 1
  • Tagged with
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Binary gas adsorption on molecular sieves : experimental data for the adsorption of oxygen, nitrogen and oxygen-nitrogen mixtures on five molecular sieve adsorbents at various temperatures and pressures and a comparison with theoretical models

Sorial, George Ayad January 1982 (has links)
A study of adsorption equilibria of oxygen, nitrogen and oxygen-nitrogen mixtures on types 4A, 5A, 13X and Na-Mordenite molecular sieve pellets has been made. Pure component isotherms, using a volumetric apparatus, have been measured for each gas on each adsorbent at pressures up to 9 bar and for temperatures of 278.15,293.15 and 303.15 K. Curve fitting of the pure canponent isotherms has been attempted using the kinetic model of Gonzalez and Holland, the vacancy solution model, the statistical thermodynamic model and a mathematical equation similar to the Hill-de Boer model. With the exception of the kinetic model, good curve fitting was obtained. Binary equilibria data have been measured, using a constant volume method, for mixtures of oxygen and nitrogen at pressures of 1.7 and 4.4 bar and at temperatures of 278.15,293.15 and 303.15 K for each of the adsorbents. These results have been presented graphically as equilibrium phase compositions and corresponding total adsorption loadings. The binary experimental equilibria data have been examined against values predicted by mixture models (kinetic model, the extended vacancy solution model, the statistical thermodynamic model, the Cook and Basmadjian model, and the ideal adsorbed solution theory) using regression parameters obtained from the pure component isotherms. The statistical thermodynamic model and the ideal adsorbed solution theory gave the best representation of the experimental data. The activity coefficients of the adsorbed phase for the binary experimental data have been calculated and the results showed no appreciable deviation of the adsorbed phase from ideality.
2

Models for predicting powder-polymer properties and their use in injection molding simulations of aluminum nitride

Kate, Kunal H. 13 December 2012 (has links)
Powder injection molding (PIM) is widely used to manufacture complex-shaped ceramic and metal components in high production volumes. In order to design and fabricate PIM components, it is important to know a number of material properties at different powder- polymer compositions. In this thesis, several predictive models for estimating rheological, thermal and mechanical properties as a function of powder-polymer mixtures were evaluated using experimental data obtained from the literature. Based on this survey, models were selected for predicting rheological, thermal and mechanical properties for aluminum nitride-polymer mixtures at various volume fractions of powder using experimental measurements of unfilled and filled polymers. The material properties were estimated for two aluminum nitride powder-polymer mixtures and used in mold-filling simulations. These results will provide new perspectives and design tools for identifying useful material compositions, component geometry attributes, and process parameters while eliminating expensive and time-consuming trial-and-error practices prevalent in PIM. / Graduation date: 2013

Page generated in 0.0839 seconds