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Phytoformations Of Silver And Gold Nanoparticles, Brooke A. Fridley
Phytoformations Of Silver And Gold Nanoparticles, Brooke A. Fridley
Graduate Theses, Dissertations, and Problem Reports
Stevia and red beet suspension cultures were examined for uptake of silver from AgNO3 solution. Alfalfa and mung bean sprouts were also studied for silver accumulation when grown in AgNO3 solution. AA analysis confirmed the presence of silver in both sprouts and suspension cultures after exposure to AgNO3 solution, despite the toxic effects of silver on the living matter.;Extract from Pelargonium graveolens underwent reaction with both AgNO3 and KAuCl4 to form silver or gold nanoparticles. For the reaction with AgNO3, light was required to initiate the reaction. In contrast, reactions producing gold nanoparticles did not require light to react. Oxygen …
Dynamic Model Of Circulating Fluidized Bed, Yue Huang
Dynamic Model Of Circulating Fluidized Bed, Yue Huang
Graduate Theses, Dissertations, and Problem Reports
Circulating fluidized beds (CFBs) are used in many processes in the chemical industry to reduce pollution and increase efficiency. Optimization and control of CFBs are very important and require an accurate, real time, dynamic model to describe and quantify the process.;The present work focuses on modeling the transient behavior of large CFB units, whose flow characteristics were shown to yield C-shaped voidage profiles using cork as the fluidized material and air at ambient conditions.;The riser is modeled in two ways: (1) as a set of well-mixed tanks connected in series; (2) as a 1-D axisymetric cluster flow. The tanks-in-series model …
Evaluation Of Carbon Materials For Use In A Direct Carbon Fuel Cell, Gregory A. Hackett
Evaluation Of Carbon Materials For Use In A Direct Carbon Fuel Cell, Gregory A. Hackett
Graduate Theses, Dissertations, and Problem Reports
The Direct Carbon Fuel Cell (DCFC) is an efficient, environmentally friendly way to supply the United States with electrical power using its abundant coal reserves. The cell employs a process by which carbon is directly converted to electricity, without the need for combustion or gasification. The thermodynamic efficiency of a DCFC is 80%. The purpose of this research is to renovate fuel cell test stands provided by the US DOE, and to investigate the operation of the DCFC with a variety of solid carbons from several sources. The highly organized carbon form, graphite, is used as the benchmark of the …
Pitch Foam Production By Use Of Physical Blowing Agents, Mark E. Heavner
Pitch Foam Production By Use Of Physical Blowing Agents, Mark E. Heavner
Graduate Theses, Dissertations, and Problem Reports
Carbon foam is a material with many unique characteristics and proposed applications. Demanding processing requirements make many of the applications uneconomical. In this study, the possibility of impressing external physical blowing agents (PBA) into pitch is investigated to form pitch foam, a precursor to carbon foam. This would reduce processing pressure and temperature requirements and decrease the cost of manufacturing. Two pitches have been characterized and have thermoplastic character similar to organic polymers. Several physical properties were measured for 110°C and 180°C softening point pitch which were supplied by Koppers Inc. and compared to select common polymers. PBAs are frequently …
Study Of The Dynamic Behavior Of Tablet Movement In A Rotating Drum Using Discrete Element Modeling (Dem) Method, Yongxin Song
Study Of The Dynamic Behavior Of Tablet Movement In A Rotating Drum Using Discrete Element Modeling (Dem) Method, Yongxin Song
Graduate Theses, Dissertations, and Problem Reports
Particle shape is a very important factor affecting the accuracy of discrete element modeling (DEM) simulations. Therefore, the purpose of this study is to determine its effect on the dynamic behavior of tablet movement in a rotating drum. First, the shape of typical standard round tablets was represented using the intersection of three convex spherical surfaces. Contact algorithms for Tablet-Flat Surface, Tablet-Curved Surface and Tablet-Tablet were developed based on the geometry of this representation of the tablets' shape. Good agreement was obtained between the simulation results for the collision of two tablets and those obtained from experiments. In addition, simulation …
The Dissolution And Swelling Of Bituminous Coal In N-Methyl-Pyrrolidone, Joseph M. Stoffa
The Dissolution And Swelling Of Bituminous Coal In N-Methyl-Pyrrolidone, Joseph M. Stoffa
Graduate Theses, Dissertations, and Problem Reports
Research detailed herein examined the extraction and swelling of a bituminous coal in the super solvent n-methyl-pyrrolidone. Correlations were developed to describe the extraction and swelling observed in the coal-solvent system. These correlations describe swelling and extraction based on experimental parameters such as extraction time and extraction temperature. The research concluded that swelling and extraction may be related processes. The most significant result of the research was a proposed relationship between the rapidness of coal swell and the coal's solubility in the solvent. The research served as support for coal structure models and solvent extraction mechanisms published in peer reviewed …
Partial Oxidation Of Propane On Ceria- And Alumina-Supported Platinum Catalysts, Vijaya Anil Bansode
Partial Oxidation Of Propane On Ceria- And Alumina-Supported Platinum Catalysts, Vijaya Anil Bansode
Graduate Theses, Dissertations, and Problem Reports
Three Pt/CeO2 catalysts and Pt/Al2O3 catalyst were studied for partial oxidation of propane. The 1% Pt/CeO 2 (C) catalyst which was prepared using CeO2 prepared by the decomposition technique showed the highest propane conversion and hydrogen selectivity. The 1% Pt/Al2O3 showed better performance than 1% Pt/CeO2 (C).;The effect of flow rate was studied for 0.01 g and 0.02 g of 1% Pt/CeO 2 (C) and 1% Pt/Al2O3. Oxygen is totally consumed at all flow rates, even at 0.01 g catalyst loading for both catalysts. The total oxidation of propane is taking place first followed by steam reforming along with water …
Barrier Properties Of Polymer Nanocomposites During Cyclic Sorption-Desorption And Stress-Coupled Sorption Experiments, Suneetha Burla
Barrier Properties Of Polymer Nanocomposites During Cyclic Sorption-Desorption And Stress-Coupled Sorption Experiments, Suneetha Burla
Graduate Theses, Dissertations, and Problem Reports
It is well known that layered silicate nanoparticles, when distributed within the matrix of a polymer, can retard the diffusion of small molecules and improve barrier properties. This has been demonstrated in both sorption and permeation experiments in the past. In order to assess the long-term retention of barrier properties of polymer-layered silicate nanocomposites, it becomes important to study their response to various environmental effects.;The main theme of this investigation is to study the effect of several water exposure cycles and exposure coupled with external tensile stress on the barrier properties of various polymers like vinyl ester, polyester and epoxy …
Bimetallic Carbides As Catalysts For Dry Reforming And Steam Reforming, Huifang Shao
Bimetallic Carbides As Catalysts For Dry Reforming And Steam Reforming, Huifang Shao
Graduate Theses, Dissertations, and Problem Reports
In this work, a series of novel bimetallic carbide catalysts has been successfully prepared in house, by changing the metallic elements therein and the ratio of CO2/CO in carburization process. Co-W-C and Ni-W-C are the elements in the bimetallic carbides to be discussed in this dissertation. Following the preparation, different techniques were applied to characterize the catalyst from the bulk phase to the surface.;For Co-W-C, the catalytic evaluation were carried out for three reactions, methane dry reforming (DRM), methane steam reforming (SRM) and methanol steam reforming (SRMeOH). This bimetallic carbide is stable and active for DRM after proper pretreatment, while …
Model And Software Development For Predicting Fish Growth In Trout Raceways, Yin-Han Wang
Model And Software Development For Predicting Fish Growth In Trout Raceways, Yin-Han Wang
Graduate Theses, Dissertations, and Problem Reports
A software program was built using Visual Basic for Applications (VBA) in MicrosoftRTM Excel. The purpose of the software is to allow users to manage their raceways more efficiently by providing a tool to simulate the performance of an existing raceway or to predict the behavior of a raceway under a wide variety of operating scenarios. The program considers the behavior of a system of multiple raceways arranged both in series and parallel configurations, and allows for the addition, removal and combination of different cohorts at different times in different raceways. Input data required include properties of the incoming water …
Studies To Investigate Variables Affecting Coating Uniformity In A Pan Coating Device, Preetanshu Pandey
Studies To Investigate Variables Affecting Coating Uniformity In A Pan Coating Device, Preetanshu Pandey
Graduate Theses, Dissertations, and Problem Reports
The purpose of this study was to investigate the variables that affect the mass coating variability (CV) in a pan coating process. A novel video-imaging technique was used to record the movement of tablets inside the pan. The effects of pan loading, pan speed and particle shape were studied. The response variables were circulation time, surface time, projected surface area, dynamic angle of repose, cascading velocity (2 directions), and dispersion coefficient. Experiments were conducted at 3 different pan speeds, 6, 9 and 12 rpm, and two pan loadings. The circulation time ranged from 2.8-10.8 s, depending on the operating condition, …