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A Real-Time Approach To Process Monitoring Of Heavy Metals: Spectrophotometric Characterization And Application Of Novel Azo, Joseph Timothy Labeots

Theses and Dissertations

I will describe studies in developing an on-line system for process monitoring that is based upon spectrophotometric methods. Heavy metals that are discarded into the environment may pose severe threats to public health, and are thus heavily regulated. Currently, there is no reasonably affordable, reliable, real-time monitoring method for heavy metals in water. This lack of feedback for industrial applications often leads to wasted resources due to massive overtreatment to avoid costly penalties. Spectrophotometry is a viable analysis option assuming a suitable sensor molecule is available as seemingly conflicting requirements may occur. Characterization of the sensor is one of the …

Cooperative Lewis Pairs Based On High-Valent Early Transition Metal Halides And Synthesis Of Their Nitride Complexes, Md. Mamdudur Rahman

Theses and Dissertations

Herein, we report the activation of relatively strong C–H and C–O bonds under mild conditions by a cooperative interaction of TaCl5 and PPh3. An unprecedented activation of nitrile adducts of high-valent transition metals with the formation of novel zwitterionic imido complexes was observed. The scope of the reaction includes a range of substituted unactivated nitriles including the C–H bond activation of both aliphatic and aromatic nitriles.

The cooperative action of a Lewis acidic high-valent transition metal halide (TaCl5 or NbCl5) and a weakly nucleophilic base (NEt3 or PPh3) leads to the deprotonation of a coordinated nitrile and subsequent rearrangement to …

Fracture Toughness And Fatigue Crack Growth Rate Characterization Of Inconel 718 Formed By Laser Powder Bed Fusion, Charles C. Hohnbaum

Theses and Dissertations

Continuing improvement in the field of AM of metals provides the opportunity for direct fabrication of aerospace parts. AM was once used in large part for rapid prototyping but improvements in technology and increases in the knowledge base of AM materials has provided the opportunity for manufacture of AM parts for operational use. The ability to create low numbers of unique parts without having to invest in expensive tooling provides great economic incentive to utilize this technique. IN718 is the most common high temperature alloy used in the aerospace industry and lends itself readily to formation by LPBF. The superior …