ANALYTICAL AND EXPERIMENTAL STUDY OF INVESTMENT CASTING WITH LASER STEREOLITHOGRAPHY MODELS by Wen-Long Yao This dissertation presents an analytical and experimental investigation of ceramic shell cracking during the burnout process in investment casting with internally webbed laser stereolithography (SLA) patterns. Included in the consideration are the cracking temperature of the ceramic shell...

Current article describes application of zeolites in fluid catalytic cracking (FCC). The use of several zeolitic additives for the production light olefins and reduction of pollutants is described. Application of zeolites as fluid catalytic cracking (FCC) catalysts and additives due to the presence of active acid sites in the zeolite framework  increase the formation of desired cracking product...

A full field method for the description of in-plane strain fields is applied for improving Asphalt Mixture cracking behaviour insights. A Digital Image Correlation (DIC) system based on the Least Square Matching technique is used to compute strains and depict crack path in the process from microcrack initiation to failure. A Brazilian test was performed using hole-notched specimens. The test ge...

We used an experimental model producing a tissue response with a sclerotic endosteal neo-cortical rim associated with implant loosening in humans: a 6 mm PMMA cylinder pistoned 500 m concentrically in a 7.5 mm hole, with polyethylene particles. At a second operation at eight weeks, the standard revision procedure removed the fibrous membrane in one knee, and the crack revision procedure was use...

Low cost processes, in both GaAs and Silicon, often use non-planar interconnect metals. While very efficient in simplifying processes, seam (more commonly called ‘‘crack’’) formation due to inter-level dielectric topologies can (1) cause significant thinning in the metallization, impacting the reliability and (2) act as process defects that reduces circuit yield. To better understand and monito...

This paper presents the results of channel cracking experiments performed on a multilayered structure. Room temperature creep behavior of a metallic underlayer was studied by using a newly developed channel cracking method. By the analysis of a channel crack propagating under tensile load in an elastic Si3N4 topical layer, the creep properties of an aluminum underlayer were determined. The expe...

A strategy is proposed to reduce surface tensile stresses that develop in ceramic microlaminate structures. As a specific example, surface stresses, which can lead to unwanted edge cracking, appear within a thin alumina/mullite layer bounded by thicker alumina layers after fabrication at some elevated temperature and subsequent cooling. A stress analysis is performed using the finite element me...

Modern business applications and scientific databases call for inherently dynamic data storage environments. Such environments are characterized by two challenging features: (a) they have little idle system time to devote on physical design; and (b) there is little, if any, a priori workload knowledge, while the query and data workload keeps changing dynamically. In such environments, tradition...

The authors discuss fatigue strength of welded rib-to-web junctions at the deck supports with reference to redecking of the Williamsburg and the Bronx-Whitestone bridges, where low available depth necessitated the use of special details, and recommend the use of the “modified nominal stress approach” for the design of such connections. However, experience with thousands of existing orthotropic ...

Thermodynamic analysis of the cracking of hexane has been conducted by the Gibbs free energy minimization method and second law analysis of overall reactions. By-products have been divided into three groups of methane, alkynes and aromatics and their possible production paths have been discussed. Effect of operating conditions such as temperature and steam-to-hexane ratio on the cracking perfor...