Engineering Commons^™

Modifying Casting Parameters To Improve The High Temperature Ductility Of Investment Cast Nickel-Based Superalloy Pwa 1455, Lars Alexander Hedin, Cole Magnum Introligator

Materials Engineering

PCC Structurals, an industry leader in superalloy investment castings, has observed inconsistencies in the stress rupture performance of polycrystalline nickel-based superalloy PWA 1455. PCC has changed their casting parameters to reduce the thermal gradient during cooling but have been unable to correlate these changes with an increase in stress rupture elongation. Metallographic examination of past samples indicated microstructures composed of non- equiaxed dendritic grains with mean diameter of .021 inches along the test axis. A similar study on polycrystalline superalloys has indicated that excessive superheat temperatures above the liquidus can result in large grains identical to those observed, limiting the …

Synthesis, Characterization, And Evaluation Of Metal Complexes With Cancer Selective Anti-Proliferative Effects And Hydrogen Evolution Catalytic Properties., Nicholas Vishnosky

Electronic Theses and Dissertations

Bis-thiosemicarbazones (BTSC) and their metal chelates have properties that are useful in several different scientific fields. These systems have already received attention in major fields of biology and engineering. Hydrogen evolution reaction (HER) catalysts need to be cheap and operate under minimal overpotentials with a long lifetime. The treatment of cancer requires, novel agents that have potent cytotoxic activity against cancer cells while displaying minimal side effects. In this dissertation the modular synthesis of these bis-thiosemicarbazone systems is utilized to regulate the redox chemistry for employment in the desired sector of chemistry. The ligand and metal chelates synthesized were characterized …

The Effect Of Flinak Molten Salt Corrosion On The Hardness Of Hastelloy N, David Kok

Scholar Week 2016 - present

The Molten Salt Reactor (MSR) has been identified as a promising candidate to replace aging nuclear reactors around the world. However, a suitable combination of molten salt and container material needs to be found in order to reduce the potential for corrosion in the MSR before it can be considered commercially viable. FLiNaK molten salt and the nickel-based alloy Hastelloy N have been identified as prime candidates for this function, but the severity of FLiNaK corrosion in Hastelloy N requires additional study before this combination can be used in the operation of a MSR. In this study, Hastelloy N samples …

Urea Functionalization Of Ultrasound-Treated Biochar: A Feasible Strategy For Enhancing Heavy Metal Adsorption Capacity, Baharak Sajjadi, James William Broome, Wei Yin Chen, Daniell L. Mattern, Nosa O. Egiebor, Nathan Hammer, Cameron L. Smith

Faculty and Student Publications

© 2018 Elsevier B.V. The main objective of a series of our researches is to develop a novel acoustic-based method for activation of biochar. This study investigates the capability of biochar in adsorbing Ni(II) as a hazardous contaminant and aims at enhancing its adsorption capacity by the addition of extra nitrogen and most probably phosphorous and oxygen containing sites using an ultrasono-chemical modification mechanism. To reach this objective, biochar physically modified by low-frequency ultrasound waves (USB) was chemically treated by phosphoric acid (H3PO4) and then functionalized by urea (CO(NH2)2). Cavitation induced by ultrasound waves exfoliates and breaks apart the regular …

Nickel Based Rtd Fabricated Via Additive Screen Printing Process For Flexible Electronics, Vikram S. Turkani, Dinesh Maddipatla, Binu B. Narakathu, Bilge N. Altay, Paul D. Fleming, Bradley J. Bazuin, Massood Atashbar

Bilge Nazli Altay

Effect Of Pt Promotion On The Ni-Catalyzed Deoxygenation Of Tristearin To Fuel-Like Hydrocarbons, Ryan Loe, Kelsey Huff, Morgan Walli, Tonya Morgan, Dali Qian, Robert Pace, Yang Song, Mark Isaacs, Eduardo Santillan-Jimenez, Mark Crocker

Center for Applied Energy Research Faculty and Staff Publications

Pt represents an effective promoter of supported Ni catalysts in the transformation of tristearin to green diesel via decarbonylation/decarboxylation (deCO_x), conversion increasing from 2% over 20% Ni/Al₂O₃ to 100% over 20% Ni-0.5% Pt/Al₂O₃ at 260 °C. Catalyst characterization reveals that the superior activity of Ni-Pt relative to Ni-only catalysts is not a result of Ni particle size effects or surface area differences, but rather stems from several other phenomena, including the improved reducibility of NiO when Pt is present. Indeed, the addition of a small amount of Pt to the supported Ni …

Continuous Catalytic Deoxygenation Of Waste Free Fatty Acid-Based Feeds To Fuel-Like Hydrocarbons Over A Supported Ni-Cu Catalyst, Ryan Loe, Yasmeen Lavoignat, Miranda Maier, Mohanad Abdallah, Tonya Morgan, Dali Qian, Robert Pace, Eduardo Santillan-Jimenez, Mark Crocker

Center for Applied Energy Research Faculty and Staff Publications

While commercial hydrodeoxygenation (HDO) processes convert fats, oils, and grease (FOG) to fuel-like hydrocarbons, alternative processes based on decarboxylation/decarbonylation (deCO_x) continue to attract interest. In this contribution, the activity of 20% Ni-5% Cu/Al₂O₃ in the deCO_x of waste free fatty acid (FFA)-based feeds—including brown grease (BG) and an FFA feed obtained by steam stripping a biodiesel feedstock—was investigated, along with the structure-activity relationships responsible for Ni promotion by Cu and the structural evolution of catalysts during use and regeneration. In eight-hour experiments, near quantitative conversion of the aforementioned feeds to diesel-like hydrocarbons was achieved. …

The Effect Of Flinak Molten Salt Corrosion On The Hardness Of Hastelloy N, David Kok

Honors Program Projects

The desire to reduce pollution caused by electricity production has led to a call for the replacement of conventional fossil fuel power plants. In order to fulfill this goal, a large amount of new nuclear reactors is required, and this provides the opportunity to put new and innovative reactor designs into production. The Molten Salt Reactor (MSR) is one of the most promising concepts, but a suitable combination of molten salt and container material needs to be found to reduce the potential for corrosion before the concept can be put into production. FLiNaK molten salt and the nickel-based alloy Hastelloy …