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1
Mahale, Vishal Tulshiram. "Development of copper-free NAO brake-pads." Thesis, IIT Delhi, 2019. http://eprint.iitd.ac.in:80//handle/2074/8058.
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George, Faith Olajumoke. "Chromium-free conversion coating of aluminium-copper alloys." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/chromiumfree-conversion-coating-of-aluminiumcopper-alloys(5176c8af-02af-44a8-a47f-44b5a0c2585c).html.
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Aluminium alloys are frequently pre-treated by a conversion coating before application of an organic coating in order to improve the corrosion resistance and adhesive properties of the surface and the corrosion resistance provided by the system. Chromate-containing conversion coatings are commonly used for this purpose. However, legislation limits future use of hexavalent chromium compounds due to their toxic and carcinogenic nature. Therefore, alternative, so-called chromium-free conversion coatings are being developed that are more environmentally-compliant.The purpose of the present work has therefore been to contribute to a better understanding of how the aluminium substrate affects the formation and properties of conversion coatings for adhesive bonding. In particular, a chrome-free zirconium-based conversion treatment process has been investigated as a possible replacement for conventional chromate conversion treatment. The influence of the conversion time on the thickness of the formed layer on pure aluminium was investigated using complementary surface analytical techniques. The conversion time was varied between 30 and 600 seconds.In this study, the structure and composition of zirconium-based chromium-free conversion coatings on magnetron sputtered superpure aluminium and a range of aluminium-copper alloys were characterised as a function of immersion time in the aqueous conversion bath to understand the mechanism of coating formation and protection. However, the presence of copper significantly influences the coating development and ultimately the performance of the conversion coatings formed on binary copper-containing aluminium alloys.The morphology and composition of the coatings have been probed using transmission electron microscopy, Rutherford backscattering spectroscopy and glow discharge optical emission spectroscopy, with loss of substrate through growth of the conversion coating also quantified. A comparison of the RBS spectra obtained for the superpure aluminium specimens after different immersion times revealed that zirconium (Zr) and oxygen (O) peaks were wider for longer immersion times, indicating thickening of the coating with increased immersion times. Thus, increasing the immersion time resulted in an increase in coating thickness but little change in coating composition occurred as determined by the RBS RUMP simulations. Alloying decreases the coating thickness, as well as metal consumption. Here, aspects of the corrosion behaviour of superpure aluminium and aluminium-copper alloys were also considered using electronoptical, electrochemical and surface analytical probing. The influence that short and prolonged treatment times exert on the performances of such conversion coating is discussed. The conversion coating formed after 60 s and 180 s of immersion in the zirconium-based conversion coating bath provide good corrosion resistance which can be attributed to the high stability of the compounds that constitute the surface oxide layer, and good adhesion properties.
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Lee, Lin. "Contribution to Development of Copper Free Automotive Brake Pad." OpenSIUC, 2013. https://opensiuc.lib.siu.edu/theses/1244.
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When passenger vehicle drivers hit the brakes of their cars, the friction releases airborne wear particles from the contact between rotor and brake pad onto the road which are eventually washed down storm drains and into rivers. The wear particles includes copper, which functions as solid lubricant for increasing thermal heat fade as well as increasing friction coefficient for the brake pad. Nevertheless, copper not only endangers aquatic life, but it also directly affects the economy by lowering the supply of salmon. Copper is toxic to most aquatic life and is especially harmful to the sensory systems of salmon. Copper impairs salmon's sense of smell, thus reducing their ability to escape from predators. Up to half of the copper found in waterways from urban areas are from copper brake pads and is a key factor in the reduction of salmon population. In 2010, Washington and California each passed laws to ban production of brake pads containing more than 0.5% copper which will be effective in 2025. Since then, several other states including New York, Rhode Island, and Oregon have all introduced similar bills to ban copper brake pads. The raw materials that were added to the newly developed copper free sample brake pads are geopolymers; they are synthetic mineral products that combine properties of polymers, ceramics and cements. Geopolymers have the characteristic of behaving as adhesive rubber in order to replace phenolic resin matrix in the brake materials also it can be harden at room temperature which can increase friction coefficient of the brake pad. Sample brake pads manufactured on site with known constituents were tested with friction assessment and screening test machine, which measured and recorded the friction coefficient and wear of the brake pad. According to the experience in the past, the sample brake pads will be analyzed with density test and Shore Durometer test. The results presented in this report shows that geopolymers brake pad shows promising results for copper replacement for low-metallic friction material. Developed copper free friction sample shows promising result of coefficient of friction of 0.44 with thickness loss of 0.62 mm from friction assessment and screening test machine compare to commercial brake pad.
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Saysell, Colin G. "Reactivity of the copper containing enzyme galactose oxidase." Thesis, University of Newcastle Upon Tyne, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307890.
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Landeen, Lee Kevin 1965. "Inactivation of Legionella pneumophila by copper-silver ions and free chlorine." Thesis, The University of Arizona, 1989. http://hdl.handle.net/10150/276997.
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Water disinfection systems utilizing electrolytically generated copper:silver ions (200:20 to 400:40 ug/L) and low levels of free chlorine (0.1 to 0.4 mg/L) were evaluated at room (21-23°C) and elevated (39-40°C) temperatures in filtered well water (pH 7.3) for their efficacy in inactivating Legionella pneumophila (ATCC 33155). A contact time of 24 hr was necessary for copper:silver (400:40 ug/L) to achieve a 3 log₁₀ reduction in bacterial numbers at room temperature. As the copper:silver concentration increased to 800:80 ug/L (K = 7.50 x 10⁻³ log₁₀ reduction/min), the inactivation rate significantly (p ≤ 0.05) increased. In water systems at room temperature with and without copper:silver (400:40 ug/L), the inactivation rates significantly increased as the free chlorine concentration increased from 0.1 mg/L (K = 0.397 log₁₀ reduction/min) to 0.4 mg/L (K = 1.047 log₁₀ reduction/min). All disinfection systems, regardless of temperature or free chlorine concentration, showed increased inactivation rates when 400:40 ug/L copper:silver was added; however, this trend was significant only at 0.4 mg/L free chlorine.
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Chiou, Ipeng 1957. "Inactivation of Listeria monocytogenes by copper, silver ions and free chlorine." Thesis, The University of Arizona, 1991. http://hdl.handle.net/10150/277992.
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The antibacterial effect of electrolytically generated copper and silver separately and combined with free chlorine on Listeria monocytogenes was evaluated in filtered well water (FWW) and autoclaved dairy process water (ADPW). The inactivation rate (k = log10 reduction/minute) was determined. Slow bactericidal effects were observed in both FWW and ADPW after exposure to 400:40 or 800:80 mug/L copper and silver compared to 0.15 mg/L chlorine. At least five hours of exposure was required for a 6 log10 reduction in the bacterial numbers with copper and silver; however, with chlorine, the exposure time was reduced to less than one minute for the FWW. Addition of 0.15 mg/L chlorine to water containing copper and silver resulted in a significantly enhanced inactivation rate as compared to chlorine alone in both FWW and ADPW. In ADPW, chlorine with copper (400, 800 mug/L) resulted in an increased k value compared to chlorine alone and copper alone.
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Starnes, Hazel Louise. "The role of copper in the free radical depolymerisation of hyaluronic acid." Thesis, University of Salford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.308285.
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Baga, Ayad Naji Omar. "Reactions of some copper complexes with hydrogen peroxide and radiation-produced free radicals." Thesis, University of Newcastle Upon Tyne, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.328136.
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Anson, Scott J. "Analysis of lead free tin-silver-copper and tin-lead solder wetting reactions." Diss., Online access via UMI:, 2007.
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Freiholtz, Oliver. "Corrosion behaviour of new lead-free brass alloys in aqueous copper (II) chloride." Thesis, KTH, Kemi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-299780.
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På grund av nya riktlinjer för användning av mässing i kontakt med dricksvatten har nya blyfria mässingslegeringar utvecklats. Det är därför av stort intresse att undersöka deras korrosionsegenskaper, såsom avzinkningshärdighet. Ett accelererat standardtest, SS-EN ISO 6509–1:2014, har använts för att bestämma avzinkningshärdighet hos mässingslegeringar. Eftersom detta standardtest utvecklades för bly-innehållande mässingslegeringar har det ännu inte fastställts huruvida denna metod också kan appliceras för fastställandet av avzinkningshärdigheten hos blyfria mässingslegeringar. Syftet med detta examensarbete var att fylla denna kunskapslucka. Detta gjordes genom att undersöka hur avzinkningsegenskaperna för tre mässingslegeringar, varav två var blyfria och en bly-innehållande, påverkades genom att ändra standardtestets parametrar. Resultaten jämfördes sedan med deras beteende i kranvatten för att bestämma testresultatens tillförlitlighet. Det visade sig att majoriteten av de erhållna resultaten för de blyfria mässingslegeringarna var i överensstämmelse med de resultat som erhölls för den blyinnehållande mässingen. Slutsatsen som kunde dras var därför att standardtestet kan användas för att bestämma avzinkningshärdighet även av blyfri mässing samt att resultaten visar på samma rangordning gällande deras egenskaper i tappvatten.Due to new regulations for the use of brass in contact with drinking water, new lead-free brass alloys have been developed. It is therefore of great interest to investigate their corrosion properties in terms of dezincification resistance. An accelerated standard test, SS-EN ISO 6509-1:2014 is used to determine the dezincification resistance of brass alloys. However, as this standard test was developed for leaded brass alloys, it has not yet been established whether this method also is suitable to assess the dezincification resistance of lead-free brass alloys. This master thesis study aimed to expand this knowledge gap by investigating how the dezincification properties of three different brass alloys, two newly developed lead-free alloys and one lead-containing alloy, were affected by changing the parameters of the standard test. The results were compared with their behaviour in tap water to determine the reliability of the ISO test. Most of the obtained results of the lead-free brass alloys were in accordance with the results obtained for the leaded brass alloy. It could therefore be concluded that the standard test can be used to assess the dezincification resistance of brass alloys and also reflect their ranking at tap water conditions.
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Fabre, Indira. "Experimental and theoretical mechanistic studies of transition-metal free and copper-catalyzed reactions." Thesis, Paris Sciences et Lettres (ComUE), 2017. http://www.theses.fr/2017PSLEE033/document.
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Cette thèse présente des travaux de méthodologie de synthèse et des études mécanistiques. Une approche complémentaire est utilisée, avec des résultats expérimentaux et des résultats théoriques issus de calculs DFT. Trois réactions ont été étudiées. La première réaction est l’alpha-arylation de cétones énolisables en l’absence de métal de transition. Elle se déroule en présence de DMF et de tBuOK. L’étude mécanistique met en évidence la formation d’une espèce riche en électrons par déprotonation du solvant. La deuxième réaction étudiée est la N-arylation de pyrazoles via la formation d’aryldiazoniums in situ. Cette réaction est catalysée au cuivre. Une évaluation de la méthode DFT la plus adaptée est présentée. Un double cycle catalytique est proposé, faisant intervenir le complexe de cuivre et l’acide acétique. La dernière réaction étudiée est la formation stéréoselective d’alkényl thioethers fluorés trisubstitués par catalyse au cuivre. La méthodologie de synthèse est présentée, suivie d’une étude mécanistique. Celle-ci révèle un mécanisme radicalaire qui peut être généralisé à d’autres substratsIn this thesis, synthetic methodology development and mechanistic studies are presented. A complementary approach, using both experiments and theoretical outcomes from DFT, is used. Three reactions were studied. The first reaction is the transition-metal free alpha-arylation of enolizable ketones. It proceeds using DMF and tBuOK. The mechanistic study reveals the formation of an electron-rich species by deprotonation of the solvent. The second reaction studied is the copper-catalyzed N-arylation of pyrazoles with arenediazonium salts generated in situ. A benchmark is performed to evaluate the best DFT methodology. A double catalytic cycle is proposed, involving copper and acetic acid. The last reaction studied is the copper-catalyzed stereoselective access to trisubstituted fluorinated alkenyl thioethers. The development of the methodology is presented. Then a mechanistic study reveals a radical mechanism that can be generalized to other substrates
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Wang, Dong. "Making dimers of light-harvesting complexes from purple bacteria using copper–free click chemistry." Thesis, Aix-Marseille, 2017. http://www.theses.fr/2017AIXM0062/document.
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Les complexes collecteurs de lumière des bactéries photosynthétiques absorbent l'énergie solaire, et transfèrent l'énergie avec grande efficacité aux centres réactionnels, siùge où elle est captée pour l'utilisation par la cellule. Nous savons peu des détails du transfert d'énergie entre les différents complexes collecteurs de lumière. Dans cette thèse, j'ai isolé différents complexes collecteurs de lumière à partir de plusieurs souches de bactéries pourpres. J'ai construit de modèles 3D par homologie et les structures possibles de dimères ont également été examinés. Les sites de pontage dans ces protéines montrent la possibilité de construire des dimères avec des structures biologiquement pertinentes. J'ai développé un protocole pour construire de dimères de protéines collectrices de lumière fortement oligomériques. Le protocole que j'ai mis en place contient trois grandes étapes : d'abord la réaction de lysines dans les complexes à un très faible degré de réaction, et la purification des protéines marquées. Ensuite, les groupes réactifs de dibenzocyclooctyne (DBCO) ou de l'azoture sont introduits au complexe. Finalement, la réaction sans cuivre de cycloaddition azoture-alcyne promue par distorsion a pour conséquence la synthèse de dimèresThe light harvesting apparatus of photosynthetic bacteria absorb the energy from sunlight and transfer the energy with high efficiency to the reaction center, where it is captured for use by the cell. We know little about the details of energy transfer between different light-harvesting complexes. In this thesis I isolated several different types of light-harvesting complex from various stains of purple bacteria. 3D models were built, based on homology modeling, and possible dimer structures were examined. The cross linking sites in these protein shown the possiblity of forming biologically relevant dimer structures. I have developed a protocol to make dimers, from highly oligomeric light harvesting proteins. The protocol developed contains three main steps: first reaction of lysines in the complex at a very low degrees of reaction and purifying the labelled protein. Then coupling the reactive groups of dibenzylcyclootyne (DBCO) or of azide separately to the different complexes. Finally, the copper free strain promoted azide-alkyne cycloaddition reaction occurred to synthesize the dimer
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Alawadhi, Meshal Y. "Microstructural evolution and mechanical properties of oxygen-free copper processed by severe plastic deformation." Thesis, University of Southampton, 2017. https://eprints.soton.ac.uk/415750/.
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This thesis presents a study on the microstructural evolution and mechanical properties of oxygen-free copper processed by equal-channel angular pressing (ECAP) and high-pressure torsion (HPT) at room temperature. Experiments were systematically conducted to examine microstructural stability and deformation mechanisms, and their influence on the mechanical properties. A significant grain refinement was attained after deforming the material by 24 passes of ECAP and 10 turns of HPT. The microstructure in the steady-state condition consisted of equiaxed ultrafine grains (UFGs) with high-angles of misorientation. Hardness values increase with increasing number of ECAP passes and HPT turns, and the microhardness distribution was relatively homogenous. ECAP and HPT samples were pulled to failure at room temperature using strain rates of 1.0×10-4 s-1, 1.0×10-3 s-1 and 1.0×10-2 s-1. The direct influence of recovery behaviour on the tensile properties was investigated. A simultaneous increase in strength and ductility were observed with increasing number of ECAP passes as well as HPT turns. This is due to occurrence of dynamic recovery at an equivalent strain of ~12 that decreases the total dislocation density and restores the work hardening ability of oxygen-free copper. Both grain boundary and dislocation strengthening mechanisms contribute to the strength of oxygen-free copper. Higher ductility but lower strength was observed when using lower strain rates. UFG copper samples produced by HPT were stored at room temperature for 12 months to investigate microstructural stability and self-annealing phenomena. The results show that the samples processed by a low number of turns exhibit lower thermal stability after storage of 12 months in comparison to the samples processed by a high number of turns. A significant decrease in the hardness was recorded near the edges of the discs processed by 1/4, 1/2 and 1 turn due to recrystallization and grain growth whereas a minor drop in hardness values were observed in the samples processed by 3, 5 and 10 turns, and this drop was related to the recovery mechanism. Tensile tests were repeated after 12 months and the results showed that the ductility was enhanced in compensation for strength. To investigate the deformation mechanism and thermal stability under high strain rates, copper samples were subjected to 1, 4 and 8 passes of ECAP and further deformed by dynamic testing. A significant grain refinement was produced in the ECAP specimens after dynamic testing which is comparable to the grain refinement produced by severe plastic deformation (SPD) techniques such as ECAP and HPT. The grain refinement mechanism was mainly by dislocation slip in the specimen processed by 1 pass whereas it was through dynamic recrystallization for the specimen processed by 8 passes. This is due to the difference in the dislocation densities and stored energy between the ECAP specimens. A 1 pass specimen has better stability than 4 and 8-pass specimens during dynamic testing. It was also shown that increasing the testing temperature and/or the strain rate can highly influence the deformation mechanism.
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Lee, Poh Wah. "DESIGN AND OPTIMIZATION OF LOW-Cu AND Cu-FREE AUTOMOTIVE BRAKE FRICTION MATERIALS." OpenSIUC, 2013. https://opensiuc.lib.siu.edu/dissertations/724.
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The purpose of this research was to generate the knowledge for formulating low-Cu and Cu-free brake friction materials without using and releasing hazardous materials that are listed on Washington State and California State Senate Bills. Model brake material samples were manufactured and tested in the Friction Assessment and Screening Test (FAST) and the full scale automotive brake dynamometer (Dyno) using a SAE J2430 test procedure. The SAE recommended a J2430 test procedure which provided the necessary data for the Brake Effectiveness Evaluation Procedure (BEEP) by the Brake Manufacturers' Council. The newly developed low-Cu and Cu-free brake friction materials were formulated by modifying a typical Non Asbestos Organic (NAO) (T-Baseline) formulation and a typical Semi-Metallic (M-Baseline) formulation. The NAO Cu-free brake friction materials contain geopolymer and natural hemp fibers as a partial replacement of phenolic resin and synthetic Kevlar fibers, respectively. Friction performance and wear data from a series of FAST tests were used to train an artificial neural network, which was used to optimize the NAO Cu-free formulations. Then, the optimized low-Cu and Cu-free brake friction materials were tested on the Dyno. Dyno test results showed that all NAO Cu-free brake friction materials have passed the Brake Effectiveness Evaluation Procedure (BEEP), did not exhibit thermal fade when temperature was increased and were slightly sensitive to speed. The NAO Cu-free brake friction materials exhibits slightly lower average friction level when compared to the baseline materials (T-Baseline). The Cu-free brake friction materials, as well as the rotors, exhibit higher wear than the detected wear on the T-Baseline material. The semi-metallic low-Cu and Cu-free brake friction materials have also passed the BEEP. Dyno test results indicated that the semi-metallic low-Cu and Cu-free friction materials did not exhibit thermal fade and were slightly sensitive to speed. The semi-metallic low-Cu and Cu-free materials exhibited lower friction level and higher wear on the pads when compared to the M-Baseline material. The semi-metallic Cu-free material outperformed the M-Baseline material in term of rotor wear. Analyses using scanning electron microscopy (SEM) and energy dispersive x-ray (EDX) microanalysis on the tested materials show that the friction surface of the T-baseline material was covered with fully developed and stable friction layer (third body) consisting mostly of Fe-oxides, different forms of carbon and compounds of materials originally present in the bulk material. The NAO Cu-free materials (T30-15 and T30-16) did not develop a sufficient friction layer. The friction layer seemed to be responsible for the detected lower wear in the T-Baseline compared to the NAO Cu-free materials (T30-15 and T30-16), and it acted as a solid lubricant on the interface between the rubbing pad and the cast iron rotor lowering the adhesive forces. The friction and wear of the T-Baseline material was controlled by adhesive mechanisms. The NAO Cu-free materials (T30-15 and T30-16) with content of geopolymer replacing phenolic resin matrix exhibited extensive abrasive wear in addition to adhesive mechanisms. The capacity to form a friction layer on the surface plays a considerable role when lowering the wear of NAO brake friction materials. The friction layer was formed by compaction and interaction of brake wear particles, and its stability and character depend on the chemistry of the bulk materials in contact as well as the temperature, pressure and sliding speed during a friction process. SEM and EDX analyses also showed that the semi-metallic pads have developed friction layer on the friction surfaces. The difference was that the M-Baseline material had well developed friction layer, but the Low-Cu (M4) and Cu-free (M5) materials, had many smaller patches of friction layer disturbed on the surfaces.
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Noren, Martin. "Electroless Copper Plating to Achieve Solderless Connections." Thesis, Luleå tekniska universitet, Institutionen för system- och rymdteknik, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-86533.
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As the world has woken up to the change in climate in recent years, people's environmental concerns are forcing companies to change and find ways to manufacture products without harming nature. One area of serious concern is the electronics industries where an ever-increasing number of products gets updated with sensors and microcomputers to be part of the internet of things. Wen more things are upgraded with electronics, it's important that the production process is as environmentally friendly as possible and that the techniques used introduces a minimum amount of disturbance to the circuits in them. To tackle this problem, this thesis presents a novel way of manufacturing PCBs without the need for soldering components, a method that increases performance and has substantial environmental benefits. When comparing conventional soldering to the electroless copper plating process presented in this thesis, electroless copper plating uses 67 times less metal and also reduces the parasitic capacitance in the PCB that comes from the solder joints. Utilizing the solder-free method means 67 times less metal needs to be mined, transported, and recycled. Moreover, since lead is a toxic heavy metal that is often part of the solder, decreasing its use in the industry is beneficial for human health and the environment. Nowadays, when the world steadily moves toward products that use technologies like 5G, technologies where higher frequencies are required, their sensitivity to capacitive disturbances from parasitics increases. In this thesis, when comparing the conventional solder method to the non-solder method to attach a capacitor, a significant reduction in phase shift of 0.9° is measured; this change is directly related to the removal of the solder and the parasitic capacitance that comes with it.
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Kostova, Vesela. "Shiga toxin targeted strategy for chemotherapy and cancer immunotherapy application using copper-free « Click » chemistry." Thesis, Sorbonne Paris Cité, 2015. http://www.theses.fr/2015USPCB144.
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Pas de résuméRecently targeted therapies appeared as attractive alternatives to classical antitumoral treatments. The approach, developed on the concept of targeting drug to cancer cells, aims to spear normal tissues and decrease the side effects. This doctoral dissertation focuses on developing new anticancer targeted treatments in the field of chemotherapy and cancer immunotherapy by exploiting an original targeting moiety, the B subunit of Shiga toxin (STxB). Its specific properties, such as, recognition with its receptor Gb3 overexpressed in cancer cells or in antigen-presenting cells, its unconventional intracellular trafficking, guided the choice of this protein as targeting carrier. This project is based in the use of copper-free Huisgen [3+2] cycloaddition as a coupling method, which led to successful preparation of various conjugates for their respective applications. The concept was first validated by STxB-biotin conjugate. The high yield of the reaction and the compatibility between the targeting carrier and the chemical ligation promoted the design of conjugates for chemotherapy and immunotherapy. Two therapeutical optimizations of previously developed strategy in STxB drug targeting delivery were investigated: synthesis of multivalent drug-conjugates and synthesis of conjugates containing a highly potent anticancer agent. Both approaches exploited three anticancer agents: SN38, Doxorubicin and Monomethyl auristatin F. The disulfide spacer, combined with various self-immolative systems, insured drug release. Two cytotoxic conjugates STxB–doxorubicin (STxB-Doxo) and STxB-monomethyl auristatin F (STxB-MMAF) were obtained in very high yield and demonstrated strong tumor inhibition activity in the nanomolar range on Gb3-positive cells. Based on the results the STxB-MMAF conjugate was investigated on a mouse model. The project aimed also to develop STxB bioconjugates for vaccine applications. Previous studies used B subunit as a targeting carrier coupled to an antigenic protein in order to induce a more potent immune response against cancer. The conjugates were prepared using a commercial linker, requiring modifying the antigen at first place, or by oxime ligation, where slightly acidic conditions promoted the coupling. Thus, the work presented herein proposed an alternative ligation via copper-free click chemistry especially for more sensitive antigenic proteins. Various types of conjugates were synthesised and investigated for their immune stimulation properties. The STxB targeting strategy was also applied to the development of a new vaccine based on coupling the targeting carrier to alpha-GalCer, one of the most potent immune stimulating agents known. The work focused on the synthesis of functionalised alpha-Galcer with an azide handle
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Wang, Huifeng. "Molecular Mass Dependent Mechanical Properties of Metal-free Click Hydrogels." University of Akron / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=akron1427901118.
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Patel, Rakesh P. "Mechanisms of haemoglobin or copper ion promoted lipid peroxidation : implications for the oxidative modification of low density lipoprotein." Thesis, University of Essex, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.337178.
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Zhanbotin, A. Zh, A. S. Yessenbekov, M. M. Saifulin, and V. V. Saiko. "Field Emission from an Array of Free-standing Copper Nanowires Grown in PET Ion-track Membranes." Thesis, Sumy State University, 2013. http://essuir.sumdu.edu.ua/handle/123456789/35319.
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There is a description of field emission from an array of free-standing copper nanowires grown in ion-beamed PET polymer films.Highly oriented, free standing cylindrical and conical copper nanowires were electrochemically grown in the pores of track etched PET films with pore density 1 106cm-2, 2 106cm-2 and 4х107cm-2. Copper nanowires were observed using scanning electron microscope, atomic force and elec-tro-force methods of scanning probe microscope. All of the nanowires showed high efficiency tunneling cur-rent (up to ~ -1uA) from metal samples to positive charged SPM cantilever.
When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/35319
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Liggett, Jennifer. "Microelectrode Investigation of Iron and Copper Surfaces Exposed to Free Chlorine Under Relevant Drinking Water Chemistries." University of Cincinnati / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1439562284.
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Kanungo, Biraja Prasad. "Variation of free volume with deformation and relaxation for copper- and zirconium based bulk metallic glasses." Connect to this title online, 2004. http://www.ohiolink.edu/etd/view.cgi?osu1092922080.
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Thesis (M.S.)--Ohio State University, 2004.Title from first page of PDF file. Document formatted into pages; contains xiii, 115 p. ; also includes graphics (some col.). Includes bibliographical references (leaves 104-113). Available online via OhioLINK's ETD Center.
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Nalagatla, Dinesh Reddy. "INFLUENCE OF SURFACE ROUGHNESS OF COPPER SUBSTRATE ON WETTING BEHAVIOR OF MOLTEN SOLDER ALLOYS." UKnowledge, 2007. http://uknowledge.uky.edu/gradschool_theses/488.
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The objective of this study is to understand the effect of surface roughness of the Cu substrate on the wetting of molten solder alloys. Eutectic Sn-Pb, pure Sn and eutectic Sn-Cu solder alloys and Cu substrates with different surface finish viz., highly polished surface, polished surface and unpolished surface were used in this work. Highly polished surface was prepared in Metallography lab, University of Kentucky while other two substrates were obtained from a vendor. Surface roughness properties of each substrate were measured using an optical profilometer. Highly polished surface was found to be of least surface roughness, while unpolished surface was the roughest. Hot-stage microscopy experiments were conducted to promote the wetting behavior of each solder on different Cu substrates. Still digital images extracted from the movies of spreading recorded during hot-stage experiments were analyzed and data was used to generate the plots of relative area of spread of solder versus time. The study of plots showed that surface roughness of the Cu substrate had major influence on spreading characteristics of eutectic Sn-Pb solder alloy. Solder showed better spreading on the Cu substrate with least surface roughness than the substrates with more roughness. No significant influence of surface roughness was observed on the wetting behavior of lead free solders (pure Sn and eutectic Sn-Cu).
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Kim, Yeong Ho. "Chromium-free consumable for welding stainless steel corrosion perspective /." Columbus, Ohio : Ohio State University, 2005. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1133285376.
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Saadalla-Nazhat, R. A. S. "Reactions of radiation-produced free radicals with copper-amino acid complexes and related compounds in aqueous solution." Thesis, University of Newcastle Upon Tyne, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.378870.
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Gupta, Shweta. "The Constitutive Behavior of Copper at High Strain Rate as Determined by the Free Expansion Ring Test." The Ohio State University, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=osu1366200117.
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Monahan, Bradley Michael. "Synthesis and Characterization of Phase-pure Copper Zinc Tin Sulfide (Cu2ZnSnS4) Nanoparticles." University of Toledo / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1404732007.
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Dubey, Brajesh Kumar. "Comparison of environmental impacts of wood treated with chromated copper arsenate (CCA)and three different arsenic-free preservatives." [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0013092.
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Sauvé, Sébastien. "Copper and aluminum free ion activity in soil solutions = L'activité inonique du cuivre et de l'aluminium dans des solutions de sols." Thesis, McGill University, 1995. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=23295.
Full textAbstract:
This thesis reports two new methods developed to study the free ion activity of aluminum and copper. Both methods could be applied to the study of other metals. The first method measures the apparent solubility of aluminum and sulfate in a dynamic, leached system. This system is believed to give a good representation of the field situation where soils are continuously leached and never at equilibrium. This study was done under three sulfate concentrations. The part of the experiment using low sulfate concentrations showed aluminum solubility control by a gibbsite-like solid phase with a log K$ sp circ$ of 7.49. It was also shown, however, that under natural soil solution concentrations of sulfate in acidic forest soils, an interaction with sulfate controls aluminum activity rather than gibbsite solubility equilibria. This interaction is either, an aluminum-sulfate solid phase or, a stoichiometric ion-pair co-adsorption of aluminum and sulfate.The second method is a simple determination of free Cu$ sp{2+}$ in soils using a cupric ion-selective electrode. Free copper has been demonstrated to be the toxicity controlling component in aquatic studies and this study was undertaken to measure free copper activity in soils. The possible interference due to ionic strength variations or the presence of aluminum in the soil solution was checked and found to be negligible. The free activity of copper (pCu$ sp{2+}$) measured in a variety of pristine and contaminated soils varied between 6.33 to 12.20 pCu$ sp{2+}$ units. Total soil copper content and acidity were shown to strongly increase copper solubility and free Cu$ sp{2+}$ activity in the soil solution extracts. (Abstract shortened by UMI.)
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De, Castro Eloisa M. "Tuning and parameter optimization of a digital integral controller for uniform droplet spray applications using lead-free tin-copper solder." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/54543.
Full textAbstract:
Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2009.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 21).
The advent of legislation restricting the use of lead in electronics requires innovation and refinement in processes for creating lead-free solder spheres for wafer bumping and other surface mount technology. Operation improvements were made upon a uniform droplet spray apparatus, and its digital integral controller was tuned for application to lead-free solder. Parameters determined included a range of initial controller command frequencies that would produce a stable image given a desired droplet diameter, and the value of the controller gain. The frequency range was determined by measuring the diameters of droplets attained at certain frequencies. The controller gain was optimized by measuring the time it took for the controller to reach its steady state at different gain values. It was determined that initial command frequency should be within ±150 Hz of that corresponding to the target diameter and an integral gain of 0.1 dB is the optimal gain for the tin-copper lead-free solder alloy, performing at par with the system specifications when in use with lead-bearing solder.
by Eloisa M. de Castro.
S.B.
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Scarazzato, Tatiana. "Treatment of a cyanide-free copper electroplating solution by electrodialysis: study of ion transport and evaluation of water and inputs recovery." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/3/3137/tde-12032018-145732/.
Full textAbstract:
The two most common commercial copper baths are the acid sulfate copper bath and the alkaline cyanide copper bath. Alkaline copper baths are mostly used to coat parts with complex geometry and to avoid galvanic deposition when depositing a metal on a less noble substrate. Because of the toxicity of cyanide compounds, alternative baths have been developed using different complexing agents. The starting point of the present study is a cyanide-free strike bath developed for copper plating on Zamak substrates developed by the Institute for Technological Research of the State of São Paulo/ Brazil. The replacement of a raw material such as cyanide must be economically advantageous and technically feasible. Therefore, this study intended to propose an alternative to the treatment of liquid wastes from the mentioned bath, aiming at simultaneous water reclamation and chemicals recovery in a closed system. The electrodialysis membrane separation process was studied, using a laboratoryscale system operating with a synthetic solution simulating the rinsing waters from the HEDP-based bath. The feasibility of the technique was evaluated by analyzing operational parameters such as ion extraction, demineralization rate, concentration rate, current efficiency for each anionic specie and average energy consumption. Because HEDP is a chelating agent, the transport of Cu(II)-HEDP chelates through anion-exchange membranes was also evaluated by means of electrochemical methods. Chronopotentiometric and current-voltage curves were constructed for different model solutions containing the same compounds as the original bath. A relation between the presence of chelates in the solutions and the fixed ion exchange group could be established. Lastly, deposition tests were performed using electrolytes containing the recycled inputs and the characteristics of the coatings were analyzed. The results showed that an electrodialysis stack using strongly basic anion-exchange membranes was suitable to produce treated solutions and a concentrate containing the ions from the bath. The concentrate could be added to the copper bath to compensate eventual drag-out losses without affecting the quality of the coatings. Thus, the application of electrodialysis was shown to be a feasible alternative for recovering water and inputs from the evaluated solution, reducing the wastewater generation and saving natural resources.Os dois banhos de cobre comerciais mais comuns são o banho ácido à base de sulfato e o banho alcalino à base de cianeto. Os banhos alcalinos são usados principalmente para recobrir peças com geometria complexa e para evitar a deposição por deslocamento galvânico quando se deposita um metal em um substrato menos nobre. Por causa da toxicidade dos compostos cianídricos, banhos alternativos vêm sendo desenvolvidos usando diferentes agentes complexantes. O ponto de partida do presente estudo é um banho toque isento de cianeto para deposição de cobre em substratos de Zamak, desenvolvido pelo Instituto de Pesquisas Tecnológicas / Brasil. A substituição de matérias-primas como o cianeto deve ser economicamente vantajosa e tecnicamente viável. Desta forma, este estudo pretendeu propor uma alternativa para o tratamento de resíduos líquidos do banho mencionado, visando à recuperação simultânea da água e das matérias-primas em um sistema fechado. Foi estudado o processo de separação por membranas de eletrodiálise, usando um sistema em escala laboratorial operando com uma solução sintética que simulava as águas de lavagem do banho à base de HEDP. A viabilidade da técnica foi avaliada por meio da análise de parâmetros operacionais, como a extração dos íons, a taxa de dessalinização, o percentual de concentração, a eficiência de corrente calculada para cada espécie iônica e o consumo médio de energia. Devido ao HEDP ser um agente quelante, o transporte de quelatos Cu(II)-HEDP através de membranas aniônicas foi avaliado por meio de métodos eletroquímicos. Curvas cronopotenciométricas e curvas corrente-potencial foram construídas para diferentes soluções sintéticas que continham os mesmos compostos que o banho original. A relação entre a presença de quelatos nas soluções e os grupos fixos de troca iônica pôde ser estabelecida. Por fim, testes de deposição foram realizados usando eletrólitos contendo os compostos reciclados e as características dos depósitos foram analisadas. Os resultados mostraram que o sistema de eletrodiálise usando membranas aniônicas contendo grupos de troca fortemente básicos pôde produzir soluções tratadas e um concentrado contendo os íons do banho. O concentrado pôde ser adicionado ao banho original para compensar eventuais perdas por arraste sem afetar a qualidade dos depósitos. Assim, a aplicação da eletrodiálise se mostrou uma alternativa viável para a recuperação de água e de insumos da solução avaliada, reduzindo a geração de efluentes e economizando recursos naturais.
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Scarazzato, Tatiana. "Treatment of a cyanide-free copper electroplating solution by electrodialysis: study of ion transport and evaluation of water and inputs recovery." Doctoral thesis, Universitat Politècnica de València, 2018. http://hdl.handle.net/10251/98502.
Full textAbstract:
Los dos baños de cobre más utilizados comercialmente son el baño ácido a base de sulfato y el baño alcalino a base de cianuro. Los baños alcalinos son utilizados principalmente para producir recubrimientos en piezas con geometría compleja y para evitar la deposición galvánica cuando se deposita un metal en un sustrato menos noble. Debido a la toxicidad de los compuestos de cianuro, se han desarrollado baños alternativos usando diferentes agentes complejantes. El punto de partida de la presente investigación es un baño primario sin cianuros para deposición de cobre en sustratos de Zamak desarrollado en el Instituto de Investigaciones Tecnológicas del Estado de Sao Paulo / Brasil. La sustitución de materias primas como el cianuro debe ser económicamente ventajosa y técnicamente viable. De esta manera, la investigación presentada pretendió proponer una alternativa para el tratamiento de residuos líquidos del baño ya mencionado con la finalidad de recuperar de manera simultánea el agua y las materias primas en un sistema cerrado. Se ha estudiado el proceso de separación por membranas de intercambio iónico, la electrodiálisis, usando un sistema en escala de laboratorio y una disolución sintética que simulaba las aguas residuales del baño a base de HEDP. Se ha evaluado la viabilidad del sistema por medio del análisis de los parámetros de operación, como la extracción de iones, la tasa de desmineralización, el porcentaje de concentración, la eficiencia de la intensidad calculada para cada especie y el consumo medio de energía. Debido a que el ácido HEDP es un agente quelante, se ha evaluado el transporte de los quelatos Cu(II) HEDP a través de membranas de intercambio de aniones por medio de métodos electroquímicos. Se han construido curvas cronopotenciométricas y curvas intensidad-potencial para diferentes disoluciones sintéticas que contenían los mismos compuestos que el baño original. Se ha establecido la relación entre la presencia de los quelatos en las disoluciones y los grupos fijos de intercambio de aniones. Por fin, se han realizado las pruebas de deposición usando electrólitos conteniendo los compuestos reciclados y se han evaluado las características de los depósitos obtenidos. Los resultados indicaron que el sistema de electrodiálisis usando membranas de intercambio de aniones con grupos de intercambio de base fuerte ha podido producir disoluciones tratadas y un concentrado conteniendo los iones del baño. Se ha podido añadir el concentrado al baño original para compensar eventuales perdidas del arrastre sin afectar la calidad de los depósitos. Por lo tanto, la aplicación de la electrodiálisis demostró ser una alternativa viable para la recuperación del agua y de las materias primas de la disolución evaluada, reduciendo la generación de residuos líquidos y ahorrando los recursos naturales.The two most common commercial copper baths are the acid sulfate copper bath and the alkaline cyanide copper bath. Alkaline copper baths are mostly used to coat parts with complex geometry and to avoid galvanic deposition when depositing a metal on a less noble substrate. Because of the toxicity of cyanide compounds, alternative baths have been developed using different complexing agents. The starting point of the present study is a cyanide free strike bath developed for copper plating on Zamak substrates developed by the Institute for Technological Research of the State of São Paulo/ Brazil. The replacement of a raw material such as cyanide must be economically advantageous and technically feasible. Therefore, this study intended to propose an alternative to the treatment of liquid wastes from the mentioned bath, aiming at simultaneous water reclamation and chemicals recovery in a closed system. The electrodialysis membrane separation process was studied, using a laboratory-scale system operating with a synthetic solution simulating the rinsing waters from the HEDP-based bath. The feasibility of the technique was evaluated by analyzing operational parameters such as ion extraction, demineralization rate, concentration rate, current efficiency for each anionic specie and average energy consumption. Because HEDP is a chelating agent, the transport of Cu(II) HEDP chelates through anion exchange membranes was also evaluated by means of electrochemical methods. Chronopotentiometric and current-voltage curves were constructed for different model solutions containing the same compounds as the original bath. A relation between the presence of chelates in the solutions and the fixed ion exchange group could be established. Lastly, deposition tests were performed using electrolytes containing the recycled inputs and the characteristics of the coatings were analyzed. The results showed that an electrodialysis stack using strongly basic anion exchange membranes was suitable to produce treated solutions and a concentrate containing the ions from the bath. The concentrate could be added to the copper bath to compensate eventual drag-out losses without affecting the quality of the coatings. Thus, the application of electrodialysis was shown to be a feasible alternative for recovering water and inputs from the evaluated solution, reducing the wastewater generation and saving natural resources.
Els dos banys de coure més utilitzats comercialment són el bany àcid a base de sulfat i el bany alcalí a base de cianur. Els banys alcalins són utilitzats principalment per a produir recobriments en peces amb geometria complexa i per a evitar la deposició galvànica quan es deposita un metall en un substrat menys noble. A causa de la toxicitat dels compostos de cianur, s'han desenrotllat banys alternatius usant diferents agents complexants. El punt de partida de la present investigació és un bany primari sense cianurs per a deposició de coure en substrats de Zamak desenrotllat en l'Institut d'Investigacions Tecnològiques de l'Estat de Sao Paulo / Brasil. La substitució de matèries primeres com el cianur ha de ser econòmicament avantatjosa i tècnicament viable. D'aquesta manera, la investigació presentada va pretendre proposar una alternativa per al tractament de residus líquids del bany ja mencionat amb la finalitat de recuperar de manera simultània l'aigua i les matèries primeres en un sistema tancat. S'ha estudiat el procés de separació per membranes d'intercanvi iònic, electrodiàlisi, usant un sistema en escala de laboratori i una dissolució sintètica que simulava les aigües residuals del bany a base d'HEDP. S'ha avaluat la viabilitat del sistema per mitjà de l'anàlisi dels paràmetres d'operació, com l'extracció d'ions, la taxa de desmineralització, el percentatge de concentració, l'eficiència de la intensitat calculada per a cada espècie i el consum mitjà d'energia. Pel fet que l'àcid HEDP és un agent quelant, s'ha avaluat el transport dels quelats Cu (II)-HEDP a través de membranes d'intercanvi d'anions per mitjà de mètodes electroquímics. S'han construït corbes cronopotenciomètriques i corbes intensitat-potencial per a diferents dissolucions sintètiques que contenien els mateixos compostos que el bany original. S'ha establit la relació entre la presència dels quelats en les dissolucions i els grups fixos d'intercanvi d'anions. Finalment, s'han realitzat les proves de deposició usant electròlits contenint els compostos reciclats i s'han avaluat les característiques dels depòsits obtinguts. Els resultats van indicar que el sistema d'electrodiàlisi usant membranes d'intercanvi d'anions amb grups d'intercanvi de base forta ha pogut produir dissolucions tractades i un concentrat que conté els ions del bany. S'ha pogut afegir el concentrat al bany original per a compensar eventuals perdudes de l'arrossegament sense afectar la qualitat dels depòsits. Per tant, l'aplicació de l'electrodiàlisi va demostrar ser una alternativa viable per a la recuperació de l'aigua i de les matèries primeres de la dissolució avaluada, reduint la generació de residus líquids i estalviant els recursos naturals.
Scarazzato, T. (2017). Treatment of a cyanide-free copper electroplating solution by electrodialysis: study of ion transport and evaluation of water and inputs recovery [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/98502
TESIS
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Peterson, Rebecca Anne 1973. "Characterization and optimization of ordering in thin films of 2,3,9,10,16,17,23,24-oktakis((2-benzyloxy)ethoxy)phthalocyaninato copper and its metal free analogue." Thesis, The University of Arizona, 1998. http://hdl.handle.net/10150/278681.
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The variables which control the degree of molecular ordering of CuPc(OC₂OBz)₈ and H₂Pc(OC₂OBz)₈ within Langmuir-Blodgett (LB) thin films were identified and optimized. Stabilizing the Langmuir film, lowering the subphase temperature, transferring to phenyl terminated substrates, and annealing lead to enhanced ordering. Infrared data confirms increased anisotrophy (dichroic ratio, R-4.6) and order (order parameter, S₂-6.5) within these films, and predicts a tilted elliptical orientation of the molecules. Small angle X-ray scattering data and atomic force microscopy images correlate, giving a column-to-column spacing of ca. 27Å and ca. 29Å, respectively. Ordered LB thin films have charge transport mobilities of ca. 1x10⁻⁴cm²V⁻¹s⁻¹ that may increase with ClO⁻₄ anion insertion. The degree of achieved ordering leads to further investigations into the applicability of LB thin films of CuPc(OC₂OBz)₈ and H₂Pc(OC₂OBz)₈ in molecular electronic devices.
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Palimkar, S. S. "Novel synthetic methodologies: ionic liquid promoted friedlander heteroannulation and palladium-catalyzed copper/ligand/solvent free carbon-carbon coupling with heterocyclization reactions." Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 2007. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/2604.
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Guddehalli, Parameswarappa Sharavathi. "Bifunctional cyclooctynes in copper-free click chemistry for applications in radionuclide chemistry nd 4-Alkylpyridine derivatives in intramolecular dearomatization and heterocycle synthesis." Diss., University of Iowa, 2011. https://ir.uiowa.edu/etd/2710.
Full textAbstract:
Part A. Bifunctional cyclooctynes in copper-free click chemistry for applications in radionuclide chemistry: A new monofluorinated cyclooctyne (MFCO) with a reasonable kinetic profile was synthesized in three steps. We have demonstrated that MFCO can be used as a lynchpin to conjugate biomolecules to radionuclide chelators using copper-free 1,3-dipolar cycloaddition reactions with azides. Many bifunctional biomolecule-chelators were synthesized, and then radiolabelled with very high radiochemical purity and specific activity. MFCO-amine analogues were also synthesized and used in construction of chelator-biomolecule conjugates (particularly, NDP-α-MSH analogues) for applications in radioimaging. Bis-MFCO based bivalent ligands with various linker lengths were also synthesized as precursors to multivalent ligands for use in cancer diagnosis and therapy.
Part B. 4-Alkylpyridine derivatives in intramolecular dearomatization and heterocycle synthesis: 4-Alkylpyridine derivatives substituted with different carbon nucleophiles were synthesized and subjected to intramolecular spirocyclization under various conditions to afford synthetically useful diazaspiro[4.5]decanes as well as diazaspiro[5.5]undecanes in good yields. The same 4-alkyl substrates were used to synthesize anhydrobase intermediates which, then participated in aldol-like condensation in the presence of Lewis acid to yield highly conjugated dihydropyridines. Acid hydrolysis produced substituted pyridines tethered with functionalized butyro- and valero lactams. The synthesis of related azaspiro[4.5]decanes and azaspiro[5.5]undecanes from reaction of
hypervalent iodine reagents with 4-methoxy-substituted benzyl and phenethyl substrates linked to β-keto amide nucleophiles was also briefly investigated.
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Magni, M. "COPPER AND RUTHENIUM COMPLEXES IN SENSITIZED SOLAR CELLS AND OPTOELECTRONICS." Doctoral thesis, Università degli Studi di Milano, 2015. http://hdl.handle.net/2434/333099.
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In perfect harmony with the "Year of Light (IYL 2015)", the thesis has been entirely centered on the concept of Light involving the development of transition metal complexes for both the conversion of light into electric energy through dye-sensitized solar cells and, conversely, the production of light starting from electricity by fabrication of electroluminescent devices. The main part of the thesis has been devoted to the sunlight-to-electricity conversion, a target that is well contextualized within the global commitment for the progressive increase of the percentage of electric energy produced by renewable resources. In this context dye-sensitized solar cells, DSSCs, are promising devices alternative to the well established technology of silicon photovoltaics for energy production from the abundant solar light. DSSCs are devices able to harvest solar light and convert it into electricity employing a sensitizer (adsorbed on a semiconductor) and a redox couple properly chosen and combined. The project have concerned the design, synthesis and characterization of both sensitizers and redox mediators constituted by ruthenium and copper-based complexes respectively, together with their final assembly into laboratory-type DSSCs to evaluate their performance. In this way an all-round study has been carried out, from molecules on paper to test benches, passing through laboratory counters. The second, minor part, of the thesis has been focused on the diametrically opposed task, the generation of light. In this context some luminescent heteroleptic complexes based on the cheap and quite abundant copper element have been proposed. The final aim has been the synthesis of efficient luminophores for fabrication of devices able to generate light applying an electric potential across two electrodes such as in organic light-emitting diodes, OLEDs, or in analogue light-emitting electrochemical cells, LECs. The light production in LED-type devices is very efficient especially compared with other traditional artificial light sources like incandescent or fluorescent lamps, and so in line with the international policy of reducing energy consumption. In conclusion the thesis project can be schematically depicted as a circular pathway that joints together two opposite but strictly interconnected concepts (i.e. light and electricity) mutually corresponding to the task and the mean, the start and the end.
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Delaney, Nathan. "Copper Capitalism: The Making of a Transatlantic Market in Metals, 1870-1930." Case Western Reserve University School of Graduate Studies / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=case1526067114476348.
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França, Mírian Cotrim. "Cloreto de cobre como novo catalisador na esterificação de ácidos graxos." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/59/59138/tde-24062013-163216/.
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Para uma produção eficiente e economicamente viável de ésteres é necessária a utilização de catalisadores durante o processo, uma vez que a transesterificação e a esterificação são reações de equilíbrio, sendo necessário deslocar o equilíbrio de reação na direção desejada. Nesse trabalho, ésteres metílicos e etílicos de ácidos graxos de cadeia longa foram produzidos usando cloretos de cobre como catalisadores. Para definir a melhor condição reacional, foram estudadas três diferentes razões em massa de AGLs de dendê/ metanol (ou etanol) / catalisador. Definida a melhor condição reacional, foram produzidos monoésteres metílicos e etílicos a partir de ácidos graxos livres do destilado da soja assim como das borras do refino correspondente do óleo de soja e de dendê. Os ésteres metílicos e etílicos foram caracterizados através das técnicas de cromatografia gasosa acoplada à espectrometria de massas (CG/MS) e ressonância magnética nuclear de prótons (RMN 1H). Observou-se que as reações empregando cloreto de cobre como catalisador reagem preferencialmente com AGLs em relação aos triésteres. Dentre esses ácidos graxos livres, os de cadeia insaturada, são os que reagem mais facilmente com o catalisador. Em relação ao álcool empregado, observou-se que as reações em etanol são mais rápidas que as realizadas em metanol, devido a facilidade de solubilização do catalisador e matéria prima lipídica no etanol. A reação com metanol, por sua vez ocorre de forma mais lenta, devido a solubilidade parcial entre os reagentes no meio e consequentemente, com separação instantânea de duas fases ao término da agitação, facilitando a extração do produto. A ampliação da estequiometria de reação em 160 e 80 vezes, para o catalisador anidro e hidratado, respectivamente, em relação a massa de AGLs de dendê foi obtida com sucesso em ambos os catalisadores, mostrando a viabilidade do emprego do cloreto de cobre como catalisador em escala industrial e a possibilidade de ser estendido a outras matérias primas. Desse modo, a utilização do cloreto de cobre como catalisador na reação de ácidos graxos livres de cadeia longa ou de óleos vegetais se constitui em uma metodologia simples e prática, sendo uma opção viável para a produção de monoalquil esteres de cadeia longa em condições brandas de reação quando comparada aos métodos já estabelecidos e utilizados inclusive em escala industrial.For an economically feasible and efficient production of esters is necessary to use catalysts in the esterification and transesterification reactions, which are reversible. It is necessary to shift the reaction equilibrium in the desired direction. In this work we developed a novel reaction to produce methyl and ethyl esters of long chain fatty acids using copper chloride as catalysts. To establish optimal reaction conditions, we studied three different mass ratios of FFAs palm (or soybean) / methanol (or ethanol) / catalyst. Employing the best reaction conditions, methyl and ethyl mono-esters were produced from free fatty acid of the soybean oil deodorization distillate (DDOS) as well as the corresponding refined soybean and palm oil. The methyl and ethyl esters were characterized by gas chromatography coupled to mass spectrometry (GC / MS) and proton nuclear magnetic resonance (1H NMR). It was observed that reactions using copper chloride as catalyst are faster with free fatty acids than with neutrals refined oils. Among these, free fatty acids of unsaturated chain react faster than the saturated ones. Regarding the alcohol employed, it was observed that the reactions in ethanol are faster than those performed in methanol, due to higher of solubility of the catalyst and feedstock lipid in ethanol. The reaction with methanol, in turn occurs more slowly, due to partial solubility of the reactants in the solvent that results in, instantaneous phases separation. The scale up of reaction at 80 and 160 times for both, anhydrous and hydrated catalyst, was successfully performed showing the feasibility of this novel process use in industrial scale. Thus, the use of copper chloride as the catalyst in the reaction of long chain free fatty acids constitutes a simple and practical methodology, being a feasible option for the production of long chain monoalkyl esters under mild conditions compared to methods already established and also used in industrial scale.
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Wu, Hao. "Catalytic Enantioselective Formations of C–B, C–C and C–Si Bonds by Organic Molecules or Transition-Metal Complexes." Thesis, Boston College, 2015. http://hdl.handle.net/2345/bc-ir:104759.
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Thesis advisor: Amir H. HoveydaCatalytic enantioselective reactions are of great importance in synthetic organic chemistry. Thus, development of efficient, selective and easily accessible catalyst for various bond formations is the main task in our laboratories. First, we have developed the first broadly applicable enantioselective boryl conjugate addition reactions to a variety of α,β-unsaturated carbonyls, promoted by a chiral Lewis basic N-heterocyclic carbene. The valuable β-boryl carbonyls were further used in complex molecule syntheses. The mechanism of these C–B bond formations was studied in details. We have also developed a practical method for enantioselective addition of an allene unit to aryl-, heteroaryl- and alkyl-substituted Boc-aldimines. These efficient C–C bond formations, catalyzed by an aminophenol-derived boron-based catalyst, were further utilized in succinct syntheses of anisomycin and epi-cytoxazone. Finally, chiral NHC–Cu complexes were employed for site-, diastereo- and enantioselective silyl conjugate additions to acyclic and cyclic dienones and dienoates. The precious enantiomerically enriched allylsilane obtained can be converted into a ketone-aldol type product, which is difficult to access through alternative methods
Thesis (PhD) — Boston College, 2015
Submitted to: Boston College. Graduate School of Arts and Sciences
Discipline: Chemistry
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Ryberg, Per. "Concerted or Stepwise? : β-Elimination, Nucleophilic Substitution, Copper Catalysed Aziridination and Ruthenium Catalysed Transfer Hydrogenation Studied by Kinetic Isotope Effects and Linear Free-Energy Relationships." Doctoral thesis, Uppsala universitet, Avdelningen för organisk kemi, 2002. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-2008.
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This thesis describes the use of kinetic isotope effects, linear free energy relationships and stereochamical studies to distinguish between different mechanistic alternatives and to obtain information about transition state structure. In the first part fluorine and deuterium kinetic isotope effects were determined for the base promoted HF elimination from 4-fluoro-4-(4’-nitrophenyl)butane-2-on. During this work a new method for the determination of fluorine kinetic isotope effects was developed. The results from the study demonstrates that the reaction proceeds via an E1cBip mechanism. In the second part the transition state structure for the SN2 reaction between ethyl chloride and cyanide ion in DMSO was studied. Kinetic isotope effects for six different positions in the reacting system, both in cyanide and ethyl chloride, were determined. The experimental isotope effects were then compared with the theoretically predicted isotope effects. The third part describes the use of Hammett type free-energy relationships and stereochemical evidence to study the mechanism of the copper catalysed alkene aziridination. The results from the study support a model that involves the simultaneous presence of two different copper nitrene intermediates. One which reacts non-stereospecifically via a radical intermediate and one which reacts stereospecifically via a concerted mechanism. In the fourth part a mechanistic study of the Ru(aminoalcohol) catalysed transfer hydrogenation of acetophenone in isopropanol is described. Kinetic isotope effects were determined for both proton and hydride transfer. The observation of significant primary deuterium kinetic isotope effects for both proton and hydride transfer support a mechanism where the proton and hydride are transferred simultaneously in a concerted mechanism.
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Chen, Jianxian. "I. Chemoselective catalytic hydrogenation of Ã, ß-unsaturated aldehydes and ketones using soluble copper(I) hydrides, II. Free radical alkylation of titanium(III) allyl and propargyl complexes." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0005/NQ39514.pdf.
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Lopez, Gerald Gabriel. "The impact of interconnect process variations and size effects for gigascale integration." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/31781.
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Thesis (Ph.D)--Electrical and Computer Engineering, Georgia Institute of Technology, 2010.Committee Chair: Jeffrey A. Davis; Committee Co-Chair: James D. Meindl; Committee Member: Azad J. Naeemi; Committee Member: Dennis W. Hess; Committee Member: George F. Riley; Committee Member: Linda S. Milor. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Sowards, Jeffrey William. "Development of a chromium-free consumable for joining stainless steel." Columbus, Ohio : Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1237845645.
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Krantz-Frid, Madelene. "Ecotoxicological effects from three antifouling paints on the red macroalga Ceramium tenuicorne." Thesis, Södertörns högskola, Institutionen för livsvetenskaper, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:sh:diva-3070.
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Antifouling paints are applied on vessels to prevent growth of fouling organisms such hasbarnacles. Presently, there are a number of different paints available on the Swedish marketwith different strategies and active substances. The paints might work by either continuouslyreleasing biocides or physically by peeling off or provide an easily cleansed surface whereorganisms cannot attach. The physically working paints do not need to register an activesubstance since its purpose is not to affect living organisms by a chemical or biological modeof action. In this study, two commercially available paints, the copper-based Fabi 3959(International Paint Ltd) and physically eroding, biocide-free labelled Mille Light (HempelFärg AB) were compared to Hard Racing superior, containing copper and the forbiddensubstance Tributyltin. Fabi International is only allowed to be used on the Swedish west coastdue to 6% added as active substance while the biocide-free Mille Light is eligible for eastcoast usage. The toxic effect from respective paint was investigated by assembling a growthinhibition test with the red macro alga Ceramium tenuicorne. The results show that all thestudied paints had a negative effect on growth and therefore leaked substances inconcentrations high enough to be harmful to the alga. The toxic response differed with theeffect on growth being in the following order, Hard racing superior>Fabi >Mille Light.Implications regarding the current legalization involving biocide-free labelled antifoulingpaints are discussed.
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Zell, Joanna. "Glycolipid - and Lectin-Dependant Endocytosis studies by a chemical biology Approch." Thesis, Sorbonne Paris Cité, 2018. https://theses.md.univ-paris-diderot.fr/ZELL_Joanna_2_complete_20181116.pdf.
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Les techniques biologiques actuelles ne permettent pas la réintroduction fonctionnelle des glycosphingolipides (GSLs) à longue chaine dans les cellules. Nous proposons de développer des outils moléculaires permettant la reconstitution des GSLs fonctionnels de manière contrôlée, en combinant le marquage métabolique et la chimie click sans cuivre. Les outils moléculaires sont validés par la toxine de Shiga, qui pénètre dans la cellule hôte indépendamment de la machinerie clathrine intracellulaire, en se liant à son récepteur cellulaire GSL, le globotriaosylcéramide (Gb3-Cer), par un mécanisme d’endocytose récemment décrit, appelé GL-Lect (glycolipide-lectine). Selon l’hypothèse GL-Lect, les lectines cellulaires ou pathogéniques induisent la constitution de puits endocytiques en réorganisant les lipides membranaires de façon à favoriser la formation de courbures membranaires locales. La technique de reconstitution des GSLs qui est décrite ici s’applique à la découverte des partenaires d’interaction des GSL dans l’étude de l’endocytose GL-LectCurrent biological techniques do not permit the functional reintroduction of long-chain glycosphingolipids (GSLs) into cells. We aim to develop molecular tools permitting cellular reconstitution of functional GSLs in a controlled manner, combining metabolic labelling of sphingolipids with copper-free click chemistry. Molecular tools are validated with the bacterial Shiga toxin, which gains entry to cells independently of the canonical intracellular clathrin machinery on binding to its GSL cell receptor, globotriaosylceramide (Gb3-Cer), through a recently described mechanism of endocytosis, termed GL-Lect (glycolipid-lectin). According to the GL-Lect hypothesis, cellular or pathogenic lectins drive the construction of endocytic pits by reorganising membrane lipids so as to favour the formation of narrow membrane curvature. The GSL reconstitution technique that is described here is applicable to the discovery of GSL binding partners in the study of GL-Lect mediated endocytosis
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Moreno, Ruben Gregorio Moreno. "Estudos de lesão ao DNA promovida pela autoxidação de S(IV) na presença de complexos de Cu(III)/tetraglicina. Efeito sinérgico de Ni(II), Co(II) e Mn(II)." Universidade de São Paulo, 2005. http://www.teses.usp.br/teses/disponiveis/46/46133/tde-04062007-032229/.
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O presente trabalho apresenta estudos de lesão em biomoléculas (DNA e 2\'-deoxiguanosina) induzida por Cu(III)/tetraglicina (Cu(III)/G4), radicais de óxidos de enxofre (SO3·-, SO4·-, SO5·-), HO· e HSO5-, espécies estas geradas durante a autoxidação de S(IV) na presença de Cu(II)/G4 ou Cu(II) (ausência de tetraglicina) e traços de um segundo íon metálico (Ni(II), Co(II) ou Mn(II)). A formação dos radicais SO3·- e HO· foi detectada pela técnica de ressonância paramagnética eletrônica (EPR). As técnicas de espectrofotometria e dicroísmo circular foram empregadas para avaliar a formação de Cu(III)/G4 em diferentes condições experimentais, na presença e ausência de S(IV), e a interação entre os complexos de cobre (II)/(III) e a molécula de DNA. A eficiência da formação de Cu(III) depende da acidez, concentração de S(IV) e dos tampões utilizados. A lesão no DNA plasmidial pUC19 foi verificada empregando-se a técnica de eletroforese em gel de agarose. A extensão da lesão no DNA depende da acidez, concentração de S(IV), tempo de incubação e da presença de um segundo íon metálico. Usando a técnica de cromatografia líquida de alta eficiência (HPLC) foi possível estudar a oxidação de 2\'-deoxiguanosina a 8-oxo-7,8-dihidro-2\'-deoxiguanosina na presença dos oxidantes fortes gerados durante a autoxidação de S(IV) catalisada por Cu(II)/G4. Um estudo comparativo do efeito de vários íons metálicos evidenciou o sinergismo de Cu(II) e traços de um segundo íon metálico (Ni(II), Co(II) ou Mn(II), complexados ou não com tetraglicina).The present work presents studies related to biomolecules damage (DNA and 2\'-deoxyguanosine) induced by Cu(III)/tetraglycine (Cu(III)/G4), oxysulfur radicals (SO3·-, SO4·-, SO5·-) and HSO5-, species generated during S(IV) autoxidation in the presence of Cu(II)/G4 or Cu(II) (absence of tetraglycine) and trace level of a second metal ion (Ni(II), Co(II) or Mn(II)). The formation of SO3·- and HO· radicals was detected by electronic paramagnetic resonance technique (EPR). Spectrophotometric and circular dichroism techniques were used to evaluate the Cu(III)/G4 formation in different experimental conditions, in the presence and the absence of S(IV), and the interaction of copper (II)/(III) complexes and DNA molecule. The effectiveness of Cu(III) formation depends on the acidity, S(IV) concentration, and buffers used. The damage on pUC 19 plasmid DNA was verified by agarose gel electrophoresis. The extent on the DNA damage was related to acidity, S(IV) concentration, incubation time and to the presence of a second metal ion. Using the high performance liquid chromatography technique (HPLC) it was possible to study the oxidation of 2\'-deoxyguanosine to 8-oxo-7,8-dihydro-2\'-deoxyguanosine in the presence of strong oxidants generated during the S(IV) autoxidation catalyzed by Cu(II)/G4. A comparative study of the effect of several metal ions showed the synergism of Cu(II) and traces of a second metal ion (Ni(II), Co(II) or Mn(II), as tetraglycine complexes or not).
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Maza, Quiroga Ricardo José. "Nucleophilic boryl motifs and alpha-borylcarbanions: reactivity and trends." Doctoral thesis, Universitat Rovira i Virgili, 2021. http://hdl.handle.net/10803/673184.
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En el Capítol 2, coure(I) catalitza la ciclació borilativa de gamma-alquenil aldehids mitjançant una adició quimio- i regioselectiva de Cu-B sobre C=C, seguida d'una reacció intramolecular d'adició de Cu-C sobre C=O. Els productes s'han format amb diastereoselectivitat i un anàlisi computacional ha identificat els punts claus que determinen la quimio- i diastereoselectivitat observada.
En el capítol 3, s'estudia la reactivitat dels compostos diborats amb diens 1,3 en un context lliure de metalls de transició. Unicament, l'addició de Na2CO3 sobre bis(pinacolat)diboro, en MeOH, permet la 1,4-hidroboració de 1,3-diens no cíclics i cíclics. La influencia electrònica del sustrat garanteix la hidroboración conjugada 1,4 versus la 1,2. Càlculs DFT mostran que la distribució de la càrrega en l'anió alílic intermedi governa la selectivitat en la 1,4-hidroboració, mentres que la configuració trans del diè determina la preferència pel producte alil-borilat E.
En el capítol 4, s'estudia la química dels carbanions alpha-borilats, ja que mostren una gran diversitat i permeten la formació d'enllaços C-C eficients. La deficiència electrònica del centre borilat trisubstituit és responsable de l'estabilizació del carbanió, facilitant la seva formació i modelant la reactivitat. Es descriuen aspectes electrònics de la estructura i tendèncias reactives d'un conjunt ampli d'alpha-boril carbanions. Mitjançant estudis de DFT s'ha determinat un mapa de tendencies sobre la reactivitar nucleòfila dels carbanions alpha-borilats, variant la naturalesa del grup borilo, el número de grups borilo en el carbanió i la naturalesa del catió estabilizant. Aquest mapa de tendencies permet la selecció del sintó apropiat, en funció de la reactivitat objecte d'estudi.egioselectiva de Cu-B sobre C=C, seguida de una reacción intramolecular de adición de Cu-C sobre C=O. Los productos se han formado con diastereoselectividad y un análisis computacional ha identificado los puntos clave que determinan la quimio- y diastereoselectividad observada. En el Capítulo 3, es estudia la reactividad de los compuestos diborados con 1,3-dienos en un contexto libre de metales de transición. La única adición de Na2CO3 sobre bis(pinacolato)diboro, en MeOH, permite la 1,4-hidroboración de 1,3-dienos no cíclicos y cíclicos. La influencia electrónica del sustrato garantiza la hidroboración conjugada 1,4 versus la 1,2. Cálculos DFT muestran que la distribución de la carga en el anión alílico intermedio gobierna la selectividad en la reacción de 1,4-hidroboración, mientras que la configuración trans del dieno determina la preferencia por el producto alil-borilado E. En el capítulo 4, se estudia la química de los carbaniones alpha-borilados, ya que muestran una gran diversidad y permiten la formación de enlaces C-C eficientes. La deficiencia electrónica del centro borilado trisustituido es responsable de la estabilización del carbanión, facilitando su formación y modelando su reactividad. Se describen aspectos electrónicos de la estructura y tendencias reactivas de un conjunto amplio de alpha-boryl carbanions. Mediante estudios de DFT se ha determinado un mapa de tendencias sobre la reactividad nucleófila de los carbaniones alpha-borilados, variando la naturaleza del grupo borilo, el número de grupos borilo en el carbanión y la naturaleza del catión estabilizante. Este mapa de tendencias permite la selección del sintón apropiado, en función de la reactividad objeto de estudio.
In Chapter 2, copper (I) catalyzes the borylative cyclization of gamma-alkenyl aldehydes through chemo- and regioselective addition of Cu-B to C=C and concomitant intramolecular 1,2-addition of Cu-C on the C=O. The products are formed in an exclusive diastereoselective manner and computational analysis identify the key points for the chemo- and diastereoselectivity observed. In Chapter 3, we study the reactivity of diboron reagents with 1,3-dienes in a transition-metal-free context. The sole addition of Na2CO3 to bis(pinacolato)diboron, in MeOH, allows the 1,4-hydroboration of cyclic and noncyclic 1,3- dienes. The electronic influence on the substrate guarantees the conjugated 1,4-hydroboration versus 1,2-diboration. DFTcalculations show that the distribution of charge in the allylic anion intermediate governs the selectivity toward 1,4- hydroboration, while the favored trans configuration in diene reagents determines the preference for the E allyl boronate products. In Chapter 4, we studied the chemistry of alpha-boryl carbanions since they show a remarkable diversity, and enable efficient C-C bond formation. The electron-deficient, trivalent boron center stabilizes the carbanion facilitating its generation and tunning its reactivity. We describe the electronic structure and the reactivity trends of a large dataset of apha-boryl carbanions. We use DFT-parameters for capturing their electronic and steric properties, computational reactivity towards model substrates, and crystallographic analysis within the Cambridge Structural Dataset. This study maps the reactivity space by systematically varying the nature of the boryl moiety, the substituents of the carbanionic carbon, the number of alpha-boryl motifs, and the metal countercation. Furthermore, we can classify the alpha-boryl alkylidene metal precursors into three classes directly related to their reactivity. This trend map aids the selection of the appropriate reactive synthon depending on the sought reactivity.
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Lanfranc, de Panthou Fabrice. "Chimie de coordination de radicaux libres nitroxydes : matériaux magnétiques incluant des ions de transition et des porteurs de spins organiques." Université Joseph Fourier (Grenoble), 1994. http://www.theses.fr/1994GRE10121.
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Les radicaux libres nitroxydes sont a la base d'un grand nombre de materiaux moleculaires. Seuls, a l'etat solide, ils peuvent conduire a des materiaux magnetiques purement organiques ; utilises comme ligands, ils permettent la synthese d'edifices moleculaires aux proprietes magnetiques variees. Des nitronyl et imino nitroxydes fonctionnalises, ont ete prepares et pour certains, des interactions ferromagnetiques intermoleculaires ont ete observees et expliquees. En particulier, l'un d'entre eux est le premier exemple bien caracterise de couplage ferromagnetique resultant de l'interaction entre aromes porteurs de densite de spin de signes opposes. Les derives de coordination de ces ligands radicalaires presentent un eventail de proprietes peu commun. En particulier, certains derives cuivriques presentent un comportement magnetique similaire aux complexes du fer(ii) au co(ii) qui transitent entre un etat haut spin et un etat bas spin. Une conversion entre des geometries de coordination axiale et equatoriale du ligand nitroxyde est la cause de cette bistabilite. La fonctionnalisation des nitroxydes 3-imidazoline en enaminocetones diversement substituees (travail effectue a novossibirsk, russie) conduit a des architectures moleculaires planes, dont certaines s'ordonnent ferromagnetiquement vers 8 k
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Білянін, Роман Володимирович. "Тепловий контроль технічного стану індукційних установок для виробництва мідної катанки." Thesis, Національний технічний університет "Харківський політехнічний інститут", 2019. http://repository.kpi.kharkov.ua/handle/KhPI-Press/41338.
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Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.11.13 – прилади і методи контролю та визначення складу речовин. – Національний технічний університет "Харківський політехнічний інститут", м. Харків, 2019 р.
У дисертації вирішено важливе наукове завдання розвитку методів теплового контролю технічного стану індукційних установок виробництва високоякісної мідної катанки на основі використання математичного моделювання електротеплових процесів, аналізу розподілу температури в багатошаровій термоізоляції установок з урахуванням її деградації та розподілу температури на їх поверхні, що має суттєве значення для розвитку кабельної промисловості. Розроблено новий метод неруйнівного контролю технічного стану індукційних установок для виготовлення мідної катанки енергетичного призначення, в якому крім вимірювання реактивного та активного опорів індуктора та різниці температури води у системі охолодження додатково визначається ступінь деградації багато-шарової термоізоляції шляхом порівняння розрахункового розподілу поточної температури в об'ємі розплаву та ізоляції на тривимірній математичній моделі установки з практичним вимірюванням температури локальних областей (у роботі їх було 72) поверхні корпусу печі. Це дає можливість точніше прогнозувати ресурс печі та завчасно виявляти режими її роботи близькі до аварійних. Розроблено нове технічне рішення з удосконалення багатошарової термоізоляції індукційних установок з метою зменшення їхніх енерговитрат і збільшення ресурсу. Воно полягає у застосуванні замість третього термоізоляційного шару з легковагої цегли трьох шарів: монолітного вогнетривкого бетону, легковагої цегли та вогнетривкого паперу, зі збереженням загальної товщини ізоляції. Впровадження результатів дисертації в індукційній установці UPCAST US20X-10 для виготовлення мідної катанки в ПАТ "ЗАВОД ПІВДЕНКАБЕЛЬ" дало позитивні результати у зниженні на 20°C температури на корпусі печі, скороченні на 5-15% питомої витрати електроенергії на 1 тонну катанки та поліпшенні її якості шляхом зменшення відсотку сторонніх домішок і забезпечення вмісту в ній міді 99,99%.The thesis for a Candidate of Engineering Sciences degree by specialty 05.11.13 – devices and methods of control and determination of composition of substances. – National technical university "Kharkov polytechnic institute", Kharkiv, 2019. The thesis solves the important scientific task to improve methods of control of the technical condition of induction installations for the production of high-quality copper rod using the mathematical modeling of electrothermal processes in copper melt and multi-layer thermal insulation, with taking into account its degradation and temperature distribution on the installation surface, which is essential for the development of cable industry. A new method of non-destructive control of the technical condition of induction installations for the production of copper rod for power cables of energy value is developed, in which in addition to measuring the reactive and active resistances of the inductor and the reduction of the water temperature in the cooling system, the degree of degradation of multilayer thermal insulation is additionally determined by comparing the calculated distribution of the current temperature in the volume of melt and insulation on a three-dimensional mathematical model of the installation with practical measurement of temperature in local areas (in the work they were 72) of the surface of the furnace casing. This makes it possible to more accurately predict the furnace's profile and to detect the modes of its operation in a timely manner close to the emergency. A new technical solution for improving the multilayer thermoinsulation of induction installations has been developed in order to reduce their energy consumption and increase the resource. It consists in applying instead of the third thermal insulation layer of light-weight brick of three layers: monolithic refractory concrete, lightweight brick and refractory paper, with the preservation of the overall thickness of the insulation. The implementa-tion of the developed lining structure improvement at PJSC " YUZHCABLE WORKS" in the UPCAST US20X-10 induction installation for copper rod in the cable industry in Ukraine has yielded positive results in a 20°C decrease in the temperature of the furnace casing, a reduction of 5-15% of the specific cost Electricity for 1 ton of production and improvement of quality of copper rod, by reducing the percentage of foreign impurities and ensuring copper content in it 99,99%.
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Білянін, Роман Володимирович. "Тепловий контроль технічного стану індукційних установок для виробництва мідної катанки." Thesis, Національний технічний університет "Харківський політехнічний інститут", 2019. http://repository.kpi.kharkov.ua/handle/KhPI-Press/41340.
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Дисертація на здобуття наукового ступеня кандидата технічних наук за спеціальністю 05.11.13 – прилади і методи контролю та визначення складу речовин. – Національний технічний університет "Харківський політехнічний інститут", м. Харків, 2019 р.
У дисертації вирішено важливе наукове завдання розвитку методів теплового контролю технічного стану індукційних установок виробництва високоякісної мідної катанки на основі використання математичного моделювання електротеплових процесів, аналізу розподілу температури в багатошаровій термоізоляції установок з урахуванням її деградації та розподілу температури на їх поверхні, що має суттєве значення для розвитку кабельної промисловості. Розроблено новий метод неруйнівного контролю технічного стану індукційних установок для виготовлення мідної катанки енергетичного призначення, в якому крім вимірювання реактивного та активного опорів індуктора та різниці температури води у системі охолодження додатково визначається ступінь деградації багато-шарової термоізоляції шляхом порівняння розрахункового розподілу поточної температури в об'ємі розплаву та ізоляції на тривимірній математичній моделі установки з практичним вимірюванням температури локальних областей (у роботі їх було 72) поверхні корпусу печі. Це дає можливість точніше прогнозувати ресурс печі та завчасно виявляти режими її роботи близькі до аварійних. Розроблено нове технічне рішення з удосконалення багатошарової термоізоляції індукційних установок з метою зменшення їхніх енерговитрат і збільшення ресурсу. Воно полягає у застосуванні замість третього термоізоляційного шару з легковагої цегли трьох шарів: монолітного вогнетривкого бетону, легковагої цегли та вогнетривкого паперу, зі збереженням загальної товщини ізоляції. Впровадження результатів дисертації в індукційній установці UPCAST US20X-10 для виготовлення мідної катанки в ПАТ "ЗАВОД ПІВДЕНКАБЕЛЬ" дало позитивні результати у зниженні на 20°C температури на корпусі печі, скороченні на 5-15% питомої витрати електроенергії на 1 тонну катанки та поліпшенні її якості шляхом зменшення відсотку сторонніх домішок і забезпечення вмісту в ній міді 99,99%.The thesis for a Candidate of Engineering Sciences degree by specialty 05.11.13 – devices and methods of control and determination of composition of substances. – National technical university "Kharkov polytechnic institute", Kharkiv, 2019. The thesis solves the important scientific task to improve methods of control of the technical condition of induction installations for the production of high-quality copper rod using the mathematical modeling of electrothermal processes in copper melt and multi-layer thermal insulation, with taking into account its degradation and temperature distribution on the installation surface, which is essential for the development of cable industry. A new method of non-destructive control of the technical condition of induction installations for the production of copper rod for power cables of energy value is developed, in which in addition to measuring the reactive and active resistances of the inductor and the reduction of the water temperature in the cooling system, the degree of degradation of multilayer thermal insulation is additionally determined by comparing the calculated distribution of the current temperature in the volume of melt and insulation on a three-dimensional mathematical model of the installation with practical measurement of temperature in local areas (in the work they were 72) of the surface of the furnace casing. This makes it possible to more accurately predict the furnace's profile and to detect the modes of its operation in a timely manner close to the emergency. A new technical solution for improving the multilayer thermoinsulation of induction installations has been developed in order to reduce their energy consumption and increase the resource. It consists in applying instead of the third thermal insulation layer of light-weight brick of three layers: monolithic refractory concrete, lightweight brick and refractory paper, with the preservation of the overall thickness of the insulation. The implementa-tion of the developed lining structure improvement at PJSC " YUZHCABLE WORKS" in the UPCAST US20X-10 induction installation for copper rod in the cable industry in Ukraine has yielded positive results in a 20°C decrease in the temperature of the furnace casing, a reduction of 5-15% of the specific cost Electricity for 1 ton of production and improvement of quality of copper rod, by reducing the percentage of foreign impurities and ensuring copper content in it 99,99%.
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Geszke-Moritz, Malgorzata. "Synthesis of stable and non-cadmium containing quantum dots conjugated with folic acid for imaging of cancer cells." Thesis, Vandoeuvre-les-Nancy, INPL, 2011. http://www.theses.fr/2011INPL066N/document.
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Les Quantum Dots (QDs) sont des particules cristallines de semi-conducteur ou du métal de forme sphérique et de dimension nanométrique. L'intérêt majeur des QDs réside dans leur grande adaptabilité à de nombreuses applications biologiques.Le but de mon travail était de développer une nouvelle classe de QDs de faible toxicité afin de les utiliser pour la bio-imagerie des cellules cancéreuses. Pour cela, il est nécessaire de préparer des sondes hydrosolubles, photostables, biocompatibles, de luminescence élevée et possédant une faible toxicité. La synthèse des cœurs de type ZnS and ZnSe dopés au manganèse ou au cuivre et stabilisés par l’acide 3-mercapropropionique ou par le 1-thioglycérol a été réalisée par la voie hydrothermale. Les techniques analytiques de caractérisation utilisées sont la spectroscopie UV-visible, la spectroscopie de fluorescence, la diffraction des rayons X (XRD), la spectroscopie photoélectronique de rayon X (XPS), la microscopie électronique à transmission (TEM), la diffusion dynamique de la lumière DLS, la spectroscopie infra-rouge (IR), et la résonance paraélectronique (RPE). La toxicité des QDs a été déterminée sur des cellules cancéreuses. Les différents test de cytotoxicité (MTT, XTT et ferrous oxidation-xylenol orange) ont été réalisés. Finalement, les QDs de type ZnS:Mn conjugués à l’acide folique ont été utilisés pour la bio-imagerie des cellules cancéreuses par le biais d’une excitation biphotoniqueSemiconductor QDs are tiny light-emitting crystals, and are emerging as a new class of fluorescent labels for medicine and biology. The aim of this work was to develop a new class of non-toxic QDs probes with essential attributes such as water dispersibility, photostability, biocompatibility, high luminescence and possible excitation with low-energy visible light, using simple processing method. Such nanoprobes could be used for bio-imaging of cancer cells. In the performed studies, I focused on ZnS and ZnSe QDs as they are cadmium-free and might be excited biphotonically.The synthesis protocols of ZnS and ZnSe QDs doped with two ions such as Mn or Cu and stabilized by 3-mercaptopropionic acid or 1-thioglycerol were established, followed by NCs characterization (diameter, surface charge, photophysical properties, …) using analytical techniques such as spectrophotometry UV-vis, fluorimetry, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), dynamic light scattering (DLS), infra-red analysis (FT-IR), thin layer chromatography (TLC) and electron paramagnetic resonance (EPR). The cytotoxicity of synthesized bare and conjugated NPs was evaluated on cancer cell lines using MTT, XTT and ferrous oxidation-xylenol orange assay.Finally, chosen well fluorescent and weakly toxic types of as-prepared and characterized QDs were used for bio-imaging of cancer cells. In these experiments, FA-functionalized NCs were excited biphotonically. The performed experiments showed the potential of QDs as cancer cells fluorescent markers and that they accumulate around the cell nuclei