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Complexation and Characterization of {(o-PPh2C6H4)CH=NCH2CH2}3N with Cu(I)¡BPd(II) and Os3 metals clusterYu, Meng-jin 02 August 2007 (has links)
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Photochemical Synthesis of Mono and Bimetallic Nanoparticles and Their Use in CatalysisPardoe, Andrea 04 May 2011 (has links)
Nanomaterials have become a popular topic of research over the years because of their many important applications. It can be a challenge to stabilize the particles at a nanometer size, while having control over their surface features.
Copper nanoparticles were synthesized photochemically using a photogenerated radical allowing spatial and temporal control over their formation. The synthesis was affected by the stabilizers used, which changed the size, dispersity, rate of formation, and oxidation rate. Copper nanoparticles suffer from their fast oxidation in air, so copper-silver bimetallic nanoparticles were synthesized in attempts to overcome the oxidation of copper nanoparticles. Bimetallic nanoparticles were synthesized, but preventing the oxidation of the copper nanoparticles proved difficult.
One important application of nanoparticles that was explored here is in catalyzing organic reactions. Because of the fast oxidation of copper nanoparticles, silver nanoparticles were synthesized photochemically on different supports including TiO2 and hydrotalcite (HTC). Their catalytic efficiency was tested using alcohol oxidations. Different silver nanoparticle shapes (decahedra and plates) were compared with the spheres to see the different catalytic efficiencies.
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Photochemical Synthesis of Mono and Bimetallic Nanoparticles and Their Use in CatalysisPardoe, Andrea 04 May 2011 (has links)
Nanomaterials have become a popular topic of research over the years because of their many important applications. It can be a challenge to stabilize the particles at a nanometer size, while having control over their surface features.
Copper nanoparticles were synthesized photochemically using a photogenerated radical allowing spatial and temporal control over their formation. The synthesis was affected by the stabilizers used, which changed the size, dispersity, rate of formation, and oxidation rate. Copper nanoparticles suffer from their fast oxidation in air, so copper-silver bimetallic nanoparticles were synthesized in attempts to overcome the oxidation of copper nanoparticles. Bimetallic nanoparticles were synthesized, but preventing the oxidation of the copper nanoparticles proved difficult.
One important application of nanoparticles that was explored here is in catalyzing organic reactions. Because of the fast oxidation of copper nanoparticles, silver nanoparticles were synthesized photochemically on different supports including TiO2 and hydrotalcite (HTC). Their catalytic efficiency was tested using alcohol oxidations. Different silver nanoparticle shapes (decahedra and plates) were compared with the spheres to see the different catalytic efficiencies.
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Modelling a Mineral Froth Flotation Process : Case Study: Minerals process at Boliden ABUr Rehman, Bilal January 2011 (has links)
We present an approach to model the dynamic of a copper flotation process. The conventional approach of system identification is applied to model the dynamics. In this research, experiments are performed to collect process data of determined input and output variables. It is followed by data pre-processing to handle outliers and to remove high frequency disturbances. Simulation and validation responses of linear estimated models, which captured the dynamic of the process, are presented. The long term goal is to use estimated models to design a models-based control system.
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Copper-Catalyzed Amination of Indoles via C-H Bond ActivationPan, Ming-kai 07 September 2012 (has links)
A new protocol for direct amination of N-Methyl-2-phenylindole catalyzed by copper(II) trifluoromethanesulfonate was presented. Both of (E)-N-(1,1'-Dimethyl-2,2'
-diphenyl-2,3'-biindolin-3-ylidene)-4-methylbenzenesulfonamide¡]4¡^and 4-methyl
-N-(1-methyl-2-phenyl-1H-indol-3-yl)benzenesulfonamide¡]2¡^were obtained under the optimal reaction conditions (2.5 mol% Cu(OTf)2, 1.2 equiv PhI=O, 0.7 equiv PhI=NTs heated at 25 ¢J in acetonitrile for 1 hour) in 78 % and 11 % yields, respectively. In addition, (E)-N-(2-hydroxy-1-methyl-2-phenylindolin-3-ylidene)-4-methylbenzene
sulfonamide ¡]6¡^and (E)-N-(1,1'-dimethyl-2,2'-diphenyl-2,3'-biindolin-3-ylidene)
-4-methylbenzenesulfonamide ¡]4¡^were synthesized in 47 % and 24 % yields, respectively, by using 5 mol% Cu(OTf)2, 2 equiv PhI=O, 1.2 equiv PhI=NTs at ambient temperature in acetonitrile for 1 hour. Finally, 4-methyl-N-(1-methyl-2-oxo-3-phenyl
indolin-3-yl)benzenesulfonamide ¡]3¡^and 1,1'-dimethyl-2,2'-diphenyl-2,3'-biindolin
-3-one ¡]7¡^can be formed under the following reaction condition, 5 mol% Cu(OTf)2, 2 equiv PhI=O, 1.2 equiv PhI=NTs and 3 equiv Ag2CO3 heated at 100 ¢J in acetonitrile for 1 hour, in 41% and 22% yields, respectively.
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Copper and zinc balance in exercising horses fed two forms of mineral supplementsWagner, Elizabeth Lynn 15 May 2009 (has links)
This study was undertaken to compare the absorption and retention of copper and zinc when supplemented to exercising horses in the form of sulfate or organic-chelate mineral supplements. Nine mature horses were used in a modified-switchback designed experiment consisting of seven 28-d periods. Horses were fed a diet consisting of 50% coastal Bermudagrass and 50% concentrate. All diets were balanced to meet the energy, protein, calcium and phosphorus requirements for horses performing moderate to intense exercise. Copper and zinc supplementation varied by period. During mineral depletion and repletion periods, horses respectively consumed diets with no supplemental mineral or Cu and Zn supplemented in the sulfate form to provide 100% of NRC (1989) values. In periods 4 and 7, horses were fed diets designed to provide 90% of NRC (1989) values for Cu and Zn supplied in the sulfate or organic-chelate forms. Horses were subjected to a standard exercise test on d 23 of periods 4 and 7 followed by a 4-d total fecal and urine collection. Blood samples were drawn every 28-d for determination of plasma Cu, Zn and ceruloplasmin concentration, and white blood cell counts and Cu,Zn-superoxide dismutase activity were evaluated in periods 4 and 7. Copper and zinc balance was determined from feed, fecal, urine and water samples obtained during the total collections in periods 4 and 7. Copper and Zn intake and fecal excretion were greater (P<0.05) for horses consuming the organic-chelate supplemented diet. Apparent Cu absorption as a percent of intake and retention as a percent of intake were also greater for this group. Plasma Cu, Zn and ceruloplasmin concentration was not different for horses consuming the two mineral supplement forms. White blood cell counts and superoxide dismutase activity were not affected by diet treatment. Formulation error and suspected sample contamination made it difficult to compare absorption and retention of Cu and Zn, but the use of a controlled repletion-depletion diet sequence appeared to be an effective experimental design component.
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Consolidation of copper and aluminum micro and nanoparticles via equal channel angular extrusionHutchins, Cathleen Ruth 15 May 2009 (has links)
Ultrafine grained (UFG), and nanocrystalline (nc) materials are of interest because of the high strength, compared with coarse grained counterparts. Several current methods to fabricate UFG and nc materials result in samples too small for practical use. In addition, the fabrication of nc materials, in particular, is difficult, and defects in the material causes significant reduction in strength and ductility of these materials. The present study uses Equal Channel Angular Extrusion (ECAE) to produce relatively large consolidates of UFG and nc materials.
ECAE has been used to consolidate micro and nanocrystalline powders. The behavior of consolidated pure Cu and aluminum alloys in the nano and micron size were explored. The effects of different routes, extrusion temperature, and post-ECAE processing on microstructure and mechanical behavior were studied. Processing parameters were explored to determine the influence of each parameter on the consolidation performance. The goals of experimenting with different processing parameters were to increase the ductility of the material, while maintaining relatively strong specimens. Comparisons were made with a recently developed powder compaction constitutive model and corresponding simulations.
ECAE of microcrystalline powders produced relatively ductile materials, with high strength. Swaging of these consolidated powders produced samples which were softer and less ductile in tension, than the non-swaged samples.
ECAE produced effective consolidation of Cu nanoparticles with average sizes of 100 nm, with an ultimate tensile strength of 680 MPa, with a fracture strain as much as 10%, which is higher than previously reported 7% [Haouaoui, 2005].
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Mercury Removal from Aqueous Systems Using Commercial and Laboratory Prepared Metal Oxide NanoparticlesDesai, Ishan 2009 August 1900 (has links)
Five commercial metal oxide nanoparticles (CuO, SiO2, Fe2O3, TiO2 and Al2O3) have been individually screened for mercury removal in a batch reactor under bicarbonate buffered and non-buffered aqueous solutions (DI water). Copper oxide was then selected for surface modification to enhance mercury removal. The surfaces of both laboratory prepared and commercially available copper oxide nanoparticles were treated with 1-octanethiol to produce
copper sulfide and/or copper alkanethiol nanoparticles. The resulting particles were characterized using
X-Ray Fluorescence(XRF),
X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). The novel nanoparticles demonstrated very high mercury removal (> 99%) from both the
buffered and non-buffered aqueous solutions.
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The Effects of the Surface Structures of CuSO4/Al2O3 catalysts on the Direct Coupling of Methane ReactionsChang, Han-Ching 14 July 2000 (has links)
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Application of copper oxide nanorods and zinc selenium quantum dots as the matrix in the surface assisted laser desorption ionization mass spectrometryChung, Feng-tsan 23 July 2008 (has links)
Abstract
Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) is a powerful tool for the analysis of biomolecules such as peptides and proteins and soft ionization technique using the organic matrix. Because of the high concentration of the organic matrix produces high background signals in the low mass range, nanopatticles have been intensively applied in the surface-assisted Laser desorption/ionization-mass spectrometry (SALDI-MS) to reduce the background interferences in the MALDI.-MS.
This thesis includes two projects. The first project applied the copper oxide nanorods, which absorbs 337 nm UV laser energy and has the large area, as the matrix for SALDI-TOF MS to detect four large antibiotics, peptides and proteins. The optimized conditions of the four antibiotic drugs were: 1000 £gM of copper oxide nanorods and incubation for 30 minutes to get the best signals. The LODs of the Lasalocid, Monensin, Salinomycin and Narasin are 200 nM, 25 nM, 50 nM and 50 nM, respectively. In addition, in this project, the CuO nanorods also can be mixed with glycerol to enhance the detection sensitivity for peptides and proteins.
The second project presents the zinc selenium quantum dots (ZnSe QDs) modified with 3-mercaptopropionic acid (3-MPA) as the matrix and affinity probes in the SALDI-TOF MS. It strengthens the interaction between the gramicidin and zinc selenium quantum dots by electric interaction in the pH 6 phosphate buffer solution according to the pI value of the gramicidin and the pKa of. 3-mercaptopropionic acid. The best sensitivity of the gramicidin can be obtained under the optimized conditions: 50 £gM of zinc selenium quantum dots, 30 minutes incubation time and pH 6 of phosphate buffer solution. The LOD of the gramicidin is 0.08 £gM. This approach also can be successfully applied in the SALDI-TOF MS to enhance the sensitivity of peptides and proteins.
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