Open Access. Powered by Scholars. Published by Universities.®
- Keyword
-
- Adsorption (1)
- Aldol condensation (1)
- Chemoselectivity (1)
- Complex oxide heterostructure (1)
- Cooperative effect (1)
-
- Diffusion (1)
- Diffusion limitations (1)
- Frequency Response (1)
- Gas separations (1)
- Heterogeneous catalysis (1)
- Hierarchical (1)
- Hierarchical zeolites (1)
- In situ SSPM (1)
- Mass Transport (1)
- Non-equilibrium capillary condensation (1)
- Oxygen ion (1)
- Oxygen vacancy (1)
- Regioselectivity (1)
- SOC (1)
- Siliceous zeolites (1)
- ZLC (1)
- Zeolite (1)
- Zeolite synthesis (1)
Articles 1 - 4 of 4
Full-Text Articles in Engineering
Controlling Selectivities In Heterogeneously Catalyzed Aldol Reactions, Koushik Ponnuru
Controlling Selectivities In Heterogeneously Catalyzed Aldol Reactions, Koushik Ponnuru
Doctoral Dissertations
Aldol condensation is an important C-C bond formation reaction in chemical synthesis that finds versatile applications in bulk and fine chemical industries and has the potential for upgrading of biomass to fuels. However, aldol reactions pose a challenge for controlling the product selectivity by forming a mixture of desired and undesired self, cross, and poly-condensation products. Furthermore, a side reaction, the fission of aldol products resulting in an olefin and a carboxylic acid, has garnered attention recently as a route to isobutene from acetone. While a high level of selectivity control is achievable by homogeneous catalysis, selective solid catalysts, which …
Quantitative Probing Of Vacancies And Ions Dynamics In Electroactive Oxide Materials, Jiaxin Zhu
Quantitative Probing Of Vacancies And Ions Dynamics In Electroactive Oxide Materials, Jiaxin Zhu
Doctoral Dissertations
Oxygen vacancy and ion dynamics in functional oxides are critical factors influencing electrical conductivity and electrochemical activity of oxides assemblies. The recent advancements in deposition and fabrication of oxide heterostructured films with atomic-level precision has led to discovery of intriguing physical properties and new artificial materials. While still under debate, researchers most often attribute these observed behaviors to unique oxygen vacancy distributions in the substrate near heterointerfaces. In electroactive oxides devices such as solid oxide cells (SOCs), oxygen vacancy and ion transport at the triple-phase boundary determines the performance of the device. This complex process motivates numerous remaining questions regarding …
Synthesis And Molecular Transport Studies In Zeolites And Nanoporous Membranes, Vivek Vattipalli
Synthesis And Molecular Transport Studies In Zeolites And Nanoporous Membranes, Vivek Vattipalli
Doctoral Dissertations
The advent of nanoporous materials such as zeolites and nanoporous membranes has provided cost-effective solutions to some of the most pressing problems of the 20th century such as the conversion of crude oil into fuels and valuable chemicals. Hierarchical zeolites and mesoporous inorganic membranes are showing great promise in addressing new problems such as the conversion of biomass into value-added chemicals and development of energy-efficient separation processes. The synthesis and fundamental aspects of molecular transport in these new materials with hierarchical porosities need to be better understood in order to rationally develop them for these desired applications. Pore narrowing …
The Investigation Of Surface Barrier During Molecular Transport In Hierarchical Zeolites, Xiaoduo Qi
The Investigation Of Surface Barrier During Molecular Transport In Hierarchical Zeolites, Xiaoduo Qi
Doctoral Dissertations
Hierarchical zeolites with micropore lengths on the order of nanometers have been synthesized with the aim of reducing mass transfer limitation. However, due to large external surface to volume ratios, the mass transport in these materials can be hindered by a secondary rate limitation step imposed on the external surface of the zeolites. This has led to the general phenomenon referred to as “surface barriers”, which cause the enhancement in mass transport being far lower than expected. In order to fully unlock the potential of hierarchical zeolites, it is imperative to fundamentally understand the molecular transport in these new types …