Current Search: Carbon (x)
Pages
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Title
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13C/12C ratios and the trophic importance of algae in Florida Syringodium filiforme seagrass meadows.
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Creator
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Fry, B., Harbor Branch Oceanographic Institute
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Date Issued
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1984
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PURL
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http://purl.flvc.org/FCLA/DT/3176733
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Subject Headings
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Algae, Carbon--Isotopes, Food chains (Ecology)
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Format
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Document (PDF)
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Title
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Physiological and growth responses of Thalassia testudinum to environmentally-relevant periods of low irradiance.
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Creator
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Kraemer, George P., Hanisak, M. Dennis
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Date Issued
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2000
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PURL
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http://purl.flvc.org/FCLA/DT/3158769
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Subject Headings
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Seagrasses, Spectral irradiance, Photosynthesis, Carbon, Nitrogen
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Format
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Document (PDF)
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Title
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Corrosion Propagation of Reinforcing Steel Embedded in Binary and Ternary Concrete.
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Creator
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Hoque, Kazi Naimul, Presuel-Moreno, Francisco, Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
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Abstract/Description
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The Florida Department of Transportation (FDOT) has been using supplementary cementitious materials while constructing steel reinforced concrete marine bridge structures for over three decades. It has been found from previous studies that such additions in concrete mix makes the concrete more durable. This research was conducted to better understand the corrosion propagation stage of steel rebar embedded in high performance concrete exposed to high humidity environment. Reinforced concrete...
Show moreThe Florida Department of Transportation (FDOT) has been using supplementary cementitious materials while constructing steel reinforced concrete marine bridge structures for over three decades. It has been found from previous studies that such additions in concrete mix makes the concrete more durable. This research was conducted to better understand the corrosion propagation stage of steel rebar embedded in high performance concrete exposed to high humidity environment. Reinforced concrete samples that were made with binary mixes, and ternary mixes were considered. None of these concretes had any admixed chloride to start with. An accelerated chloride transport method was used to drive chloride ions into the concrete so that chlorides reached and exceed the chloride threshold at the rebar surface and hence the corrosion process initiated after a short period of time (within few days to few months). Once corrosion has initiated the corrosion propagation can be studied. Electrochemical measurements such as rebar potential measurements, Linear Polarization Resistance (LPR), Electrochemical Impedance Spectroscopy (EIS), and Galvanostatic Pulse (GP) measurements were taken at regular intervals (during and after the electro-migration process) to observe the corrosion propagation in each sample. During the propagation stage, reinforcement eventually reached negative potentials values (i.e., Ecorr≤ –0.200 Vsce) for all the samples. The corrected polarization resistance (Rc) was calculated by subtracting the concrete solution resistance from the apparent polarization resistance measured. The Rc values obtained from LPR and GP measurements were converted to corrosion current (as the corroding area is unknown), and these corrosion current values measured over time were used to obtain the calculated mass loss (using Faraday’s Law). A comparison was made of the calculated corrosion current obtained using the LPR and GP tests. A comparison of mass loss was also obtained from the values measured from LPR and GP tests. From the experimental results, it was observed that the corrosion current values were largely dependent on the length of solution reservoirs. For specimens cast with single rebar as well as three rebars, the most recent corrosion current values (measurements taken between July 2018 to October 2020) in general were larger for the rebars that are embedded in specimens prepared with SL mix, followed by specimens prepared with FA, T1, and T2 mixes respectively. The range of corrosion current values (most recent) were 0.8-33.8 μA for SL samples, 0.5-22.5 μA for FA samples, 0.8-14.8 μA for T1 samples, and 0.7-10.4 μA for T2 samples respectively. It was also found that the calculated mass loss values were larger for rebars that are embedded in specimens (single rebar and three rebars) prepared with SL mix, followed by specimens prepared with FA, T1, and T2 mixes respectively. The range of calculated mass loss values were 0.07-1.13 grams for SL samples, 0.06-0.62 grams for FA samples, 0.12-0.54 grams for T1 samples, and 0.06-0.40 grams for T2 samples respectively. A variety of corrosion related parameters (Ecorr, Rs, Rc, and Icorr) and calculated theoretical mass loss values observed, were due to the changing parameters such as concrete compositions, concrete cover thickness, rebar diameter, total ampere-hour applied, and reservoir size. The specimens showed no visual signs of corrosion such as cracks or corrosion products that reached the concrete surface. The actual size of the corroding sites was unknown as the specimens were not terminated for forensic analysis. The size of the corroding sites could affect how much corrosion products are required to crack the concrete. It is speculated that the corrosion products in liquid form penetrated the pore structure but did not build up enough to cause cracks. No cracks or corrosion bleed outs were observed within the monitored propagation period of approximately 1600 days.
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Date Issued
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2020
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PURL
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http://purl.flvc.org/fau/fd/FA00013634
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Subject Headings
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Concrete, Concrete bridges--Corrosion, Carbon steel
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Format
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Document (PDF)
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Title
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Enhancing Fracture Toughness and Thermo-Mechanical Properties of Vinyl-ester Composites Using a Hybrid Inclusion of CNT and GNP.
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Creator
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Gapstur, Christopher M., Mahfuz, Hassan, Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
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Abstract/Description
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We report a method of increasing fracture toughness (KIc) and strain energy release rate (GIc) of vinyl-ester (VE) matrix by adopting a hybrid (dual) reinforcement strategy. The idea of using this strategy was to trigger intrinsic polymer-nanoparticle interaction such as carbon nanotube (CNT) pull-out and interface sliding to enhance energy absorption during fracture. Additionally, we included a second reinforcement, graphene nanoplatelets (GNP), to promote crack-deflection, crack bridging...
Show moreWe report a method of increasing fracture toughness (KIc) and strain energy release rate (GIc) of vinyl-ester (VE) matrix by adopting a hybrid (dual) reinforcement strategy. The idea of using this strategy was to trigger intrinsic polymer-nanoparticle interaction such as carbon nanotube (CNT) pull-out and interface sliding to enhance energy absorption during fracture. Additionally, we included a second reinforcement, graphene nanoplatelets (GNP), to promote crack-deflection, crack bridging and cross-linking density. Both reinforcements were dispersed into the polymer in three states: non-functionalized (nf>); functionalized with COOH (f>); surface-treated with Triton X-100 (TX100). We embarked on numerous experiments with many combinations of these variables. We measured KIc and GIc using ASTM D5045-14. We conducted an exhaustive iterative investigation with three systems (f>CNT-VE; f>GNP-VE; f>CNT-f>GNP-VE) to determine the best weight-percentage for the nanocomposite system that produced the highest KIc and GIc values when compared to neat-VE. We found that 0.5wt% f>CNT with 0.25wt% f>GNP in the VE matrix resulted in the highest fracture toughness values and was termed the optimized hybrid nanocomposites (OHN) system. Subsequently, we explored further increasing the KIc and GIc of OHN through altering the nanoparticle surface characteristics, which led to four OHN groups: f>CNT-f>GNP-VE; f>CNT-f>GNP-TX100-VE; nf>CNT-nf>GNP-TX100-VE; nf>CNT-nf>GNP-VE. We discovered that the OHN group with non-functionalized nanofillers that were TX100 surface treated (0.5wt%nf>CNT-0.25wt%nf>GNP-TX100-VE) generated the greatest improvements in KIc and GIc. Ultimately, we observed that the KIc of neat-VE increased by 65%, from 1.14 to 1.88 MPa*(m½). The improvement in GIc was even greater with an increase of 166%, from 370 to 985 J/(m2). Differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) studies showed a minor shift in glass transition temperature (Tg) by up to 8°C when comparing neat-VE specimens to OHN specimens. A similar increase in maximum thermal decomposition temperature (Tp) of up to 8°C was observed through thermogravimetric analysis (TGA) and derivative TGA (DTG). Scanning electron microscope (SEM) studies revealed that the source of improvements in fracture toughness and thermal properties was primarily the three-dimensional hybrid nanostructures (3DHN) that formed by binding CNT and GNP together, which caused an increase in nanoparticle surface area and inhibited agglomerations.
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Date Issued
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2018
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PURL
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http://purl.flvc.org/fau/fd/FA00013062
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Subject Headings
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Carbon nanotubes., Graphene., Vinyl ester resins.
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Format
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Document (PDF)
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Title
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THE IMPACT OF NUTRIENT LOADING ON THE SOIL AND ROOT RESPIRATION RATES OF FLORIDA MANGROVES.
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Creator
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Faron, Natalie Therese, Benscoter, Brian, Florida Atlantic University, Department of Biological Sciences, Charles E. Schmidt College of Science
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Abstract/Description
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Coastal nutrient loading is a growing concern in urbanized communities and has led to alterations in above- and belowground processes throughout estuarine systems. Mangrove forests are highly productive coastal habitats that exhibit large carbon stocks contained mostly to the deep soils. Since nutrient enrichment has been found to increase mangrove aboveground growth, it’s presumed that nutrient enrichment will also increase belowground respiration rates. Disturbances in soil nutrient content...
Show moreCoastal nutrient loading is a growing concern in urbanized communities and has led to alterations in above- and belowground processes throughout estuarine systems. Mangrove forests are highly productive coastal habitats that exhibit large carbon stocks contained mostly to the deep soils. Since nutrient enrichment has been found to increase mangrove aboveground growth, it’s presumed that nutrient enrichment will also increase belowground respiration rates. Disturbances in soil nutrient content may alter the mangrove carbon cycle by increasing the amount of CO2 lost to the atmosphere from enhanced microbial and root respiration. In this study, soil respiration responded greatest to nitrogen enrichment, but pneumatophore root respiration responded greatest to phosphorus enrichment. Nutrient limitation can shift between different ecological processes and responses to nutrient enrichment tend to be system specific in tidally influenced ecosystems. Understanding the implications of coastal nutrient loading will improve ecosystem models of carbon exchange and belowground processes.
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Date Issued
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2021
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PURL
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http://purl.flvc.org/fau/fd/FA00013767
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Subject Headings
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Mangrove forests, Soil respiration, Carbon cycle (Biogeochemistry)
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Format
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Document (PDF)
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Title
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Carbon nano-fibers for electrochemical double-layer capacitors.
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Creator
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Cao, Xuejun., Florida Atlantic University, Lipka, Stephen M.
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Abstract/Description
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A novel carbon nano-fiber was prepared using catalytic vapor phase growth. Electrochemical capacitors were assembled using these fibers. Physical analysis was conducted on the carbon nano-fibers and electrochemical analysis was performed on capacitors made from these carbon nano-fibers. Scanning electron microscopy revealed that the nano-fibers had diameters ranging from 20nm to 400nm. X-ray diffraction showed the nano-fibers were more ordered than some commercial carbon fibers. BET...
Show moreA novel carbon nano-fiber was prepared using catalytic vapor phase growth. Electrochemical capacitors were assembled using these fibers. Physical analysis was conducted on the carbon nano-fibers and electrochemical analysis was performed on capacitors made from these carbon nano-fibers. Scanning electron microscopy revealed that the nano-fibers had diameters ranging from 20nm to 400nm. X-ray diffraction showed the nano-fibers were more ordered than some commercial carbon fibers. BET adsorption yielded specific surface areas of the nano-fibers at around 400 m$\sp2$/g. Electrochemical studies including cyclic voltammetry and electrochemical impedance spectroscopy indicated that capacitors made from carbon nano-fibers were promising for practical use. Further modification/activation of the carbon nano-fibers was conducted and capacitors made from these materials were also evaluated.
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Date Issued
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1999
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PURL
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http://purl.flvc.org/fcla/dt/15622
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Subject Headings
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Capacitors, Electric double layer, Carbon fibers
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Format
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Document (PDF)
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Title
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Effect of fiber sterilization atmosphere on insertion of lithium into PAN-based carbon filter electrodes.
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Creator
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Braun, James Christian., Florida Atlantic University, Lipka, Stephen M.
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Abstract/Description
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A novel electrode structure for Li-ion batteries was created by thermally treating nonwoven polyacrylonitrile (PAN) fabric in an inert atmosphere. Rapid carbonization of PAN fiber, stabilized in an inert atmosphere, produced a fused carbon fiber structure having a reversible specific capacity for lithium above 300 mAh/g; with charge reversibility between 95 and 100%. Chemical, structural and electrochemical analyses, including electrochemical impedance spectroscopy were performed on carbon...
Show moreA novel electrode structure for Li-ion batteries was created by thermally treating nonwoven polyacrylonitrile (PAN) fabric in an inert atmosphere. Rapid carbonization of PAN fiber, stabilized in an inert atmosphere, produced a fused carbon fiber structure having a reversible specific capacity for lithium above 300 mAh/g; with charge reversibility between 95 and 100%. Chemical, structural and electrochemical analyses, including electrochemical impedance spectroscopy were performed on carbon fiber electrodes. Scanning electron microscopy revealed grooves and striations on the surfaces of carbon fibers prepared from PAN precursors stabilized in oxygen; but could not resolve any surface features on the fused carbon fibers, prepared from PAN precursors stabilized in an inert atmosphere. The fused, porous carbon fibers are believed to contain a large fraction of carbon chains with relatively few carbon planes.
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Date Issued
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1997
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PURL
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http://purl.flvc.org/fcla/dt/15484
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Subject Headings
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Lithium cells, Electrodes, Carbon, Nonwoven fabrics
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Format
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Document (PDF)
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Title
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The effects of substrate, surface finish, flow rate and exposure duration on calcareous deposits.
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Creator
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Mantel, Katherine Elizabeth., Florida Atlantic University, Hartt, William H., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
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Abstract/Description
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The effect of substrate finish and composition, flow rate and exposure duration on the composition, morphology and protective properties of calcareous deposits formed during cathodic polarization of several steels in seawater has been investigated. The current density behaviour of the scale formation in conjunction with morphology and composition characteristics indicated that the substrate finish and composition did not influence the nucleation or growth of the deposit. The results strongly...
Show moreThe effect of substrate finish and composition, flow rate and exposure duration on the composition, morphology and protective properties of calcareous deposits formed during cathodic polarization of several steels in seawater has been investigated. The current density behaviour of the scale formation in conjunction with morphology and composition characteristics indicated that the substrate finish and composition did not influence the nucleation or growth of the deposit. The results strongly suggest a relationship between electrolyte velocity, current density behaviour and morphology. With increased flow and consequent higher current density requirements, results indicated a low nucleation rate of CaCO3. The current density behaviour and composition of the calcareous deposit revealed a growth progression of a Mg rich film formed in the first few minutes, followed by an increasingly uniform surface coverage by CaCO3 in the form of aragonite.
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Date Issued
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1989
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PURL
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http://purl.flvc.org/fcla/dt/14575
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Subject Headings
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Steel--Cathodic protection, Calcium carbonate
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Format
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Document (PDF)
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Title
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Lithium intercalation into PAN-based carbon fiber materials.
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Creator
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Nechev, Kamen S., Florida Atlantic University, Lipka, Stephen M., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
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Abstract/Description
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High energy density PAN-based carbon fiber anode materials for lithium-ion type batteries were developed. Commercially available organic precursors were thermally converted to carbons. The effects of precursor material, carbonization temperature, heating ramp rate, soak time and gaseous atmosphere during the thermal treatment on the electrochemical performance of the carbon fibers were studied. In order to evaluate the electrochemical performance of the carbon fibers, test cells were assemble...
Show moreHigh energy density PAN-based carbon fiber anode materials for lithium-ion type batteries were developed. Commercially available organic precursors were thermally converted to carbons. The effects of precursor material, carbonization temperature, heating ramp rate, soak time and gaseous atmosphere during the thermal treatment on the electrochemical performance of the carbon fibers were studied. In order to evaluate the electrochemical performance of the carbon fibers, test cells were assemble using the carbon materials prepared in the laboratory and intercalation/deintercalation experiments were performed. The results indicated that the highest reversible capacity and lowest irreversible capacity loss was obtained for carbon fibers carbonized at 1100C at fast ramp rate of 26C/min. X-ray diffraction experiments revealed a relation between the capacity and the irreversible capacity loss on first cycle, and the size of the crystallites Lc. A phenomenological explanation for this behavior was developed. Using electrochemical impedance spectroscopy the diffusion coefficient of Li in the tested carbon fibers was calculated. In addition, the influence of electrolyte composition (solvent and salt) on the reversible and irreversible capacities as well as on the intercalation/deintercalation potential profile was investigated. An electrolyte containing 1M LiPF6 in EC:DEC:DMC (40:30:30 v/o) proved to be most suitable for these carbon fiber materials improving significantly their electrochemical performance. Finally, coin cells were assembled containing the carbon fiber material prepared in the laboratory. They were tested for reversible and irreversible capacity. The coin cells proved that the synthesized carbon anode materials possess high energy density and could be used in commercial applications.
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Date Issued
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1996
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PURL
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http://purl.flvc.org/fcla/dt/12471
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Subject Headings
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Lithium cells, Carbon fibers, Electric batteries
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Format
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Document (PDF)
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Title
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Electrochemical behavior of carbon fiber cathode materials in organic electrolytes containing various lithium salts.
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Creator
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Durand, Severine Nathalie., Florida Atlantic University, Lipka, Stephen M.
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Abstract/Description
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The intercalation of anions into carbon fiber from organic electrolytes containing lithium salts was studied. The reversible intercalation of anions into carbon could lead to the possible substitution of conventional metal oxide cathode materials in lithium-ion cells. EWC300 was selected as the most suitable carbon fiber material based on data from preliminary tests. Experiments were performed with LiClO4 in EC/DMC and LiPF6 in EC/DMC electrolytes. Slow scan cyclic voltammetry (0.1 mV/s) and...
Show moreThe intercalation of anions into carbon fiber from organic electrolytes containing lithium salts was studied. The reversible intercalation of anions into carbon could lead to the possible substitution of conventional metal oxide cathode materials in lithium-ion cells. EWC300 was selected as the most suitable carbon fiber material based on data from preliminary tests. Experiments were performed with LiClO4 in EC/DMC and LiPF6 in EC/DMC electrolytes. Slow scan cyclic voltammetry (0.1 mV/s) and galvanostatic charge/discharge experiments at various C rates were used. Intercalation of PF6- occurred by staging and was highly dependent on the current density. High current density (20 mA/g) was necessary to reach potentials over 5 V vs Li to achieve intercalation capacities over 80 mAh/g. Powder x-ray diffraction revealed that carbon fibers became less crystalline after anions were intercalated into their structure. Scanning electron microscopy showed longitudinal cracking on the carbon fibers after 120 cycles indicating dimensional instability.
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Date Issued
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1999
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PURL
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http://purl.flvc.org/fcla/dt/15624
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Subject Headings
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Anions, Carbon fibers, Lithium cells, Electrochemical analysis
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Format
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Document (PDF)
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Title
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CONVERSION OF WASTE MATERIALS TO ACTIVATED CARBON ADSORBENTS FOR BIOGAS PURIFICATION.
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Creator
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Guirard, Mitchell, Lashaki, Masoud Jahandar, Florida Atlantic University, Department of Civil, Environmental and Geomatics Engineering, College of Engineering and Computer Science
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Abstract/Description
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The potential of plastic waste-derived activated carbon was investigated for the removal of carbon dioxide and hydrogen sulfide from biogas. Activated carbon materials were prepared by carbonizing plastic waste followed by activation via microwave heating after mixing with potassium hydroxide. Samples were tested using thermogravimetric analysis to determine the equilibrium uptake of carbon dioxide. Samples were modified with tetraethylenepentamine and diethanolamine however, sample texture...
Show moreThe potential of plastic waste-derived activated carbon was investigated for the removal of carbon dioxide and hydrogen sulfide from biogas. Activated carbon materials were prepared by carbonizing plastic waste followed by activation via microwave heating after mixing with potassium hydroxide. Samples were tested using thermogravimetric analysis to determine the equilibrium uptake of carbon dioxide. Samples were modified with tetraethylenepentamine and diethanolamine however, sample texture produced was deemed unusable for further testing due to operational concerns. Adsorbent screening was conducted in conditions mimicking that of biogas at a temperature of 40 °C and 30% carbon dioxide in nitrogen. Performant samples were identified as those achieving uptakes greater than 3 wt.%. The best performing sample achieved an uptake of 3.57 wt.% and maintained 99% of its uptake during cycling. Column breakthrough experiments demonstrated that the final candidate achieved complete removal of both carbon dioxide and hydrogen sulfide, suggesting viability for larger scale biogas purification.
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Date Issued
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2022
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PURL
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http://purl.flvc.org/fau/fd/FA00014093
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Subject Headings
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Biogas--Purification, Carbon, Activated, Thermogravimetry
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Format
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Document (PDF)
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Title
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WASTE DERIVED ACTIVATED CARBON MATERIALS FOR LANDFILL GAS PURIFICATION.
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Creator
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Thomas, Ryan, Lashaki, Masoud Jahandar, Florida Atlantic University, Department of Civil, Environmental and Geomatics Engineering, College of Engineering and Computer Science
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Abstract/Description
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The potential of paper waste-derived activated carbon was investigated for the removal of carbon dioxide and hydrogen sulfide from landfill gas. Activated carbon materials were prepared by carbonizing paper waste followed by acid treatment to remove ash, mixing with aqueous phase potassium hydroxide, and activation via microwave heating. Activated samples were tested using thermogravimetric analysis to determine their equilibrium uptake of carbon dioxide. The adsorbent materials were modified...
Show moreThe potential of paper waste-derived activated carbon was investigated for the removal of carbon dioxide and hydrogen sulfide from landfill gas. Activated carbon materials were prepared by carbonizing paper waste followed by acid treatment to remove ash, mixing with aqueous phase potassium hydroxide, and activation via microwave heating. Activated samples were tested using thermogravimetric analysis to determine their equilibrium uptake of carbon dioxide. The adsorbent materials were modified with both tetraethylenepentamine and diethanolamine to potentially increase the carbon dioxide uptake, however, all the modified samples had a performance significantly worse than their unmodified counterparts. Adsorbent screening was conducted in conditions mimicking that of landfill gas, namely temperature of 40 °C and 40% carbon dioxide in nitrogen. Performant samples were identified as those achieving uptakes greater than 3 wt.%. The best performing sample achieved an uptake of 5.03 wt.% and maintained 97% of its uptake during 100 successive adsorption-desorption cycles. Column-breakthrough experiments demonstrated that the final candidate achieved complete removal of both carbon dioxide and hydrogen sulfide, suggesting viability for larger scale landfill gas purification.
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Date Issued
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2022
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PURL
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http://purl.flvc.org/fau/fd/FA00014106
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Subject Headings
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Landfill gases--Purification, Carbon, Activated, Adsorption
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Format
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Document (PDF)
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Title
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NANOPARTICLE-INDUCED CATALYTIC CARBON CAPTURE: A MICROFLUIDICS APPROACH.
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Creator
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Donjuan, Joshua, Kim, Myeongsub, Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
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Abstract/Description
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Due to technological advancement, energy consumption and demand have been increasing significantly, primarily satisfied by fossil fuel consumption. This reliance on fossil fuels results in substantial greenhouse gas emissions, with CO₂ being the most prominent contributor to global warming. To mitigate this issue and prevent CO₂ emissions, Carbon Capture, Utilization, and Storage (CCUS) technologies are employed. Among these, the amine scrubbing method is widely used due to its high CO2...
Show moreDue to technological advancement, energy consumption and demand have been increasing significantly, primarily satisfied by fossil fuel consumption. This reliance on fossil fuels results in substantial greenhouse gas emissions, with CO₂ being the most prominent contributor to global warming. To mitigate this issue and prevent CO₂ emissions, Carbon Capture, Utilization, and Storage (CCUS) technologies are employed. Among these, the amine scrubbing method is widely used due to its high CO2 capture efficiency and regenerative ability. However, this method has drawbacks, including high toxicity, corrosion, and substantial freshwater consumption. To develop an environmentally sustainable carbon capture solution, researchers are exploring alternatives such as the use of seawater and enhanced CO2 capture with catalysts. In this study, we analyze the catalytic performance of nickel nanoparticles (NiNPs) in seawater with carboxymethyl cellulose (CMC) polymers. Using flow-focusing geometry-based microfluidic channels, we investigated CO₂ dissolution at various concentrations of nanoparticles and CMC polymers. The objective is to optimize the concentration of nanoparticles and CMC polymers for effective CO₂ dissolution. We utilized NiNPs with diameters of 100 nm and 300 nm in CMC concentrations of 100 ml/L, 200 ml/L, and 300 ml/L. Additionally, NiNP concentrations ranging from 6 mg/L to 150 mg/L were tested for CO₂ dissolution in seawater. The results indicated that a concentration of 10 mg/L NiNPs in 100 mg/L CMC provided a CO₂ dissolution of 57%, the highest for this specific CMC concentration. At CMC concentrations of 200 ml/L and 300 ml/L, NiNP concentrations of 70 mg/L and 90 mg/L achieved CO₂ dissolution rates of 58.8% and 67.2%, respectively.
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Date Issued
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2024
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PURL
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http://purl.flvc.org/fau/fd/FA00014483
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Subject Headings
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Carbon sequestration, Global warming, Polymer chemistry, Nanoparticles
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Format
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Document (PDF)
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Title
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SYNERGETIC COMBINATION OF SEAWATER AND POLYMER-COATED NICKEL NANOPARTICLES FOR CO2 CAPTURE.
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Creator
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Abhishek, Kim, Myeongsub, Florida Atlantic University, Department of Ocean and Mechanical Engineering, College of Engineering and Computer Science
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Abstract/Description
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Due to technological advancement, energy consumption and demand have been increasing significantly, primarily satisfied by fossil fuel utilization. The dependence on fossil fuels results in substantial greenhouse gas emissions, with CO₂ being the principal factor in global warming. Carbon capture technologies are employed to mitigate the escalated CO₂ emissions into the atmosphere. Among various carbon capture methods, amine scrubbing is widely utilized because of its high CO2 capture...
Show moreDue to technological advancement, energy consumption and demand have been increasing significantly, primarily satisfied by fossil fuel utilization. The dependence on fossil fuels results in substantial greenhouse gas emissions, with CO₂ being the principal factor in global warming. Carbon capture technologies are employed to mitigate the escalated CO₂ emissions into the atmosphere. Among various carbon capture methods, amine scrubbing is widely utilized because of its high CO2 capture efficiency and ease of adaptability to the existing power plants. This method, however, presents drawbacks, including increased toxicity, corrosiveness, and substantial freshwater use. To overcome these shortcomings and simultaneously develop an environmentally sustainable carbon capture solution, this study aims to evaluate the CO2 capture performance of seawater associated with polyvinylpyrrolidone (PVP) polymer-coated nickel nanoparticles (NiNPs) catalysts. Using high-speed bubble-based microfluidics, we investigated time-dependent size variations of CO2 bubbles in a flow-focusing microchannel, which is directly related to transient CO₂ dissolution into the surrounding solution. We hypothesize that the higher surface-to-volume ratio of polymer-coated NiNPs could provide a higher CO2 capture rate and solubility under the same environmental conditions. To test this hypothesis and to find the maximum performance of carbon capture, we synthesized polymer-coated NiNPs with different sizes of 5 nm, 10 nm, and 20 nm. The results showed that 5 nm polymer-coated NiNPs attained a CO₂ dissolution rate of 77% while it is 71% and 43% at 10 nm and 20 nm NPs, respectively. This indicates that our hypothesis is proven to be valid, suggesting that the smaller NPs catalyze CO2 capture effectively with using the same amount of material, which could be a game changer for future CO2 reduction technologies. This unique strategy promotes the future improvement of NiNPs as catalysts for CO2 capture from saltwater.
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Date Issued
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2024
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PURL
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http://purl.flvc.org/fau/fd/FA00014557
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Subject Headings
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Nickel nanoparticles, Polyvinylpyrrolidone, Seawater, Carbon dioxide mitigation
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Format
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Document (PDF)
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Title
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Carbon Dioxide scrubbing materials in life support equipment.
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Creator
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Wang, Tsen C., Harbor Branch Oceanographic Institute
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Date Issued
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1982
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PURL
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http://purl.flvc.org/fau/fd/FA00007000
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Subject Headings
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Carbon dioxide, Life Support Systems, Carbon dioxide--Absorption and adsorption
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Format
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Document (PDF)
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Title
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An automated system of sample analysis for a total carbon analyser.
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Creator
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Fitzgerald, L., Montgomery, John R., Holt, John K., Harbor Branch Oceanographic Institute
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Date Issued
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1984
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PURL
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http://purl.flvc.org/FCLA/DT/3351926
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Subject Headings
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Carbon, Seawater--Analysis, Seawater--Analysis--Automation, Seawater--Carbon dioxide content
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Format
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Document (PDF)
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Title
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Effects of Carbon Nanotube (CNT) Dispersion and Interface Condition on Thermo-Mechanical Behavior of CNT-Reinforced Vinyl Ester.
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Creator
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Sabet, Seyed Morteza, Mahfuz, Hassan, Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
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Abstract/Description
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In fabrication of nanoparticle-reinforced polymers, two critical factors need to be taken into account to control properties of the final product; nanoparticle dispersion/distribution in the matrix; and interfacial interactions between nanoparticles and their surrounding matrix. The focus of this thesis was to examine the role of these two factors through experimental methodologies and molecular-level simulations. Carbon nanotubes (CNTs) and vinyl ester (VE) resin were used as nanoparticles...
Show moreIn fabrication of nanoparticle-reinforced polymers, two critical factors need to be taken into account to control properties of the final product; nanoparticle dispersion/distribution in the matrix; and interfacial interactions between nanoparticles and their surrounding matrix. The focus of this thesis was to examine the role of these two factors through experimental methodologies and molecular-level simulations. Carbon nanotubes (CNTs) and vinyl ester (VE) resin were used as nanoparticles and matrix, respectively. In a parametric study, a series of CNT/VE nanocomposites with different CNT dispersion conditions were fabricated using the ultrasonication mixing method. Thermomechanical properties of nanocomposites and quality of CNT dispersion were evaluated. By correlation between nanocomposite behavior and CNT dispersion, a thermomechanical model was suggested; at a certain threshold level of sonication energy, CNT dispersion would be optimal and result in maximum enhancement in properties. This threshold energy level is also related to particle concentration. Sonication above this threshold level, leads to destruction of nanotubes and renders a negative effect on the properties of nanocomposites. In an attempt to examine the interface condition, a novel process was developed to modify CNT surface with polyhedral oligomeric silsesquioxane (POSS). In this process, a chemical reaction was allowed to occur between CNTs and POSS in the presence of an effective catalyst. The functionalized CNTs were characterized using TEM, SEM-EDS, AFM, TGA, FTIR and Raman spectroscopy techniques. Formation of amide bonds between POSS and nanotubes was established and verified. Surface modification of CNTs with POSS resulted in significant improvement in nanotube dispersion. In-depth SEM analysis revealed formation of a 3D network of well-dispersed CNTs with POSS connections to the polymer. In parallel, molecular dynamics simulation of CNT-POSS/VE system showed an effective load transfer from polymer chains to the CNT due to POSS linkages at the interface. The rigid and flexible network of CNTs is found to be responsible for enhancement in elastic modulus, strength, fracture toughness and glass transition temperature (Tg) of the final nanocomposites.
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Date Issued
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2016
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PURL
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http://purl.flvc.org/fau/fd/FA00004628, http://purl.flvc.org/fau/fd/FA00004628
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Subject Headings
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Carbon nanotubes., Carbon composites., Polymeric composites., Fibrous composites, Nanostructured materials., Composite materials--Mechanical properties.
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Format
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Document (PDF)
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Title
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Demonstrations and laboratory exercises in aquaculture. II. Activated carbon and ion-exchange in chemical filtration.
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Creator
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Landau, Matthew P., Scarpa, John
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Date Issued
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2001
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PURL
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http://purl.flvc.org/FCLA/DT/3352967
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Subject Headings
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Aquaculture, Carbon, Activated, Ion exchange, Filters and filtration, Demonstrations
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Format
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Document (PDF)
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Title
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Effects of seawater exchange, pH and carbon supply on the growth of Gracilaria tikvahiae (Rhodophyceae) in large-scale cultures.
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Creator
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DeBusk, T. A., Ryther, John H., Harbor Branch Oceanographic Institute
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Date Issued
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1984
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PURL
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http://purl.flvc.org/fau/fd/FA00007019
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Subject Headings
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Gracilaria, Algae culture, Seawater, Hydrogen-ion concentration, Carbon
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Format
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Document (PDF)
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Title
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Decompression cycling effects on the shelf life of lithium hydroxide.
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Creator
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Wang, Tsen C., Harbor Branch Oceanographic Institute
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Date Issued
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1975
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PURL
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http://purl.flvc.org/FCLA/DT/3338492
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Subject Headings
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Lithium hydroxide, Carbon dioxide--Absorption and adsorption, Submersibles, Decompression
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Format
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Document (PDF)
Pages