Kevin F. Loughlin

Concentration Dependence of Moisture Diffusivity in Aluminum Particle Filled Epoxy Adhesive in Salt Solutions

Moisture and aggressive ion ingress into bonded joints are primary causes of adhesive degradation. In this study, moisture diffusion behavior of aluminum-powder-filled epoxy adhesive was investigated through utilizing fluid immersion tests under complete immersion in salt solutions with varying NaCl concentrations. Aluminum powder is used in the adhesive for the purpose of improvement of its thermal properties, as demanded in a variety of industrial applications. Mass diffusivity for each specimen was determined by two methods, one using the diffusion data at early times (away from the saturation point) and the other using the data at large times (close to the saturation point). The results of the two methods were quite different, indicating that diffusivity is concentration dependent and a constant diffusivity assumption might lead to error in determining moisture diffusivity values in epoxy systems. Qualitatively, however, both methods indicated similar diffusion behavior. According to the results of both methods, the aluminum filler content did not affect the moisture diffusivity in the epoxy adhesive significantly but the effect of salt concentration was significant; the higher the salt content in the test solution, the higher the moisture diffusivity in the adhesive.

Adsorption Henry constants calculated from the entire isotherm

A method is introduced to derive adsorption Henry constants from experimental isotherm data regardless of whether the measurements extend into the Henry law region. The method uses the intersection between Henry’s law and the Gaussian isotherm model. In this way, the Henry constant can be calculated from Gaussian model parameters obtained from a fit of the model to the entire isotherm. In addition, the Gaussian model is shown to closely agree with Henry’s law over a wide range. To demonstrate the accuracy of the method, Henry constants are derived from 63 experimental isotherms collected from the literature for supercritical n alkanes on 5A zeolite. These Henry constants compare well to values found in the literature.

Saturation loadings on 13X (faujasite) zeolite above and below the critical conditions. Part III: Inorganic monatomic and diatomic species data evaluation and modeling

The saturation loadings for subcritical adsorption of inorganic monatomic and diatomic species on 13X zeolite are modeled using the modified Rackett model of Spencer and Danner (J Chem Eng Data 17:236–240, 1972) for the saturated liquid densities combined with crystallographic data for the 13X zeolite. A similar equation is derived for supercritical adsorption involving supercritical adsorbate densities and crystallographic data for the 13X zeolite. Adsorption data from the literature are first critically evaluated and then compared to the model. Log–log plots are used to determine whether each isotherm is near saturation; isotherms that exhibit a

Development of Semi-Static Steam Process for the Production of Sludge-Based Adsorbents

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Kinetics and mechanism of partial oxidation of ethane to ethylene and acetic acid over MoV type catalysts

∂lnq∂lnp slope of zero at the maximum pressure point are assumed to be saturated. The highest loading is used from each isotherm that approaches saturation. Unsaturated isotherms are not considered further. The theoretical equation satisfactorily models the available experimental data for the data that are subcritical. However, a steric factor is required in the model for iodine. 80% of the data for helium, nitrogen and oxygen are in the supercritical region; this data reveals a linear decreasing trend with increasing reduced temperature Tr. For this data a new supercritical model is developed using the reduced critical adsorbate temperature, TCAR, and the slope of the decreasing linear plot against Tr. The physical phenomena causing this effect is considered to be increasing molecular vibration in the cavity reducing the total molecular loading with temperature rise.

Moisture diffusion into epoxy adhesive: testing and modeling

The saturation loadings for subcritical adsorption of multi-atomic inorganic species, halocarbons and oxygenated hydrocarbons on 13X zeolite are modeled using the modified Rackett model of Spencer and Danner (J. Chem. Eng. Data 17(2):236–240, 1972) for the saturated liquid densities combined with crystallographic data for the 13X zeolite. A similar equation is used for supercritical adsorption involving supercritical adsorbate densities and crystallographic data for the 13X zeolite employing a different f(Tr) expression than used by Spencer and Danner. Adsorption data from the literature are first critically evaluated and then compared to the model. Log–log plots are used to determine whether each isotherm is near saturation; isotherms that exhibit a

Sorbate densities on 5A zeolite above and below the critical conditions: n alkane data evaluation and modeling

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