Tesis:

1

Clarke, D. E. "Bonding in cokes". Thesis, University of Newcastle Upon Tyne, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.372550.

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2

Hodgson, Michael John. "Bonding in semiconductors". Thesis, University of Cambridge, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240971.

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3

Xu, Hui. "Thermosonic ball bonding : a study of bonding mechanism and interfacial evolution". Thesis, Loughborough University, 2010. https://dspace.lboro.ac.uk/2134/6325.

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Thermosonic ball bonding is a key technology in electrical interconnections between an integrated circuit and an external circuitry in microelectronics. Although this bonding process has been extensively utilised in electronics packaging industry, certain fundamental aspects behind all the practice are still not fully understood. This thesis is intended to address the existing knowledge gap in terms of bonding mechanisms and interfacial characteristics that are involved in thermosonic gold and copper ball bonding on aluminium pads. The research specifically targets the fine pitch interconnect applications where a thin metal wire of approximately 20 µm in diameter is commonly used. In thermosonic ball bonding process, a thin gold or copper ball formed at the end of a wire is attached to an aluminum pad through a combination of ultrasonic energy, pressure and heat, in order to initiate a complex solid-state reaction. In this research, the mechanisms of thermosonic ball bonding were elaborated by carefully examining interfacial characteristics as the results of the bonding process by utilising dual-beam focused ion beam and high resolution transmission electron microscopy, including the breakdown of the native alumina layer on Al pads, and formation of initial intermetallic compounds (IMCs). The effect of bonding parameters on these interfacial behaviours and bonding strength is also investigated in order to establish an inter-relationship between them. Interfacial evolution in both Au-Al and Cu-Al bonds during isothermal annealing in the temperature rage from 175ºC to 250ºC was investigated and compared. The results obtained demonstrated that the remnant alumina remains inside IMCs and moves towards the ball during annealing. The IMCs are formed preferentially in the peripheral and the central areas of the bonds during bonding and, moreover, they grow from the initially formed IMC particles. Growth kinetics of Cu-Al IMCs obey a parabolic growth law before the Al pad is completely consumed. The activation energies calculated for the growth of CuAl2, Cu9Al4 and the combination (CuAl2 + Cu9Al4) are 60.66 kJ/mol, 75.61 kJ/mol, and 65.83 kJ/mol, respectively. In Au-Al bonds, Au-Al IMC growth is controlled by diffusion only at the start of the annealing process. A t^0.2-0.3 growth law can be applied to the Au-Al IMC growth after the Al pad is depleted. The sequence of IMC phase transformation in both Au-Al and Cu-Al bonds were investigated. Voids in Au-Al bonds grow dramatically during annealing, however, only a few voids nucleate and grow very slowly in Cu-Al bonds. The mechanisms of void formation, including volumetric shrinkage, oxidation and metal diffusion were proposed and discussed.

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4

Cornes, Stuart. "Halogen bonding, hydrogen bonding and Lewis acidic receptors for anion recognition". Thesis, University of Oxford, 2016. https://ora.ox.ac.uk/objects/uuid:0725f9c4-ff44-4158-b94e-9bcaf0fa3b4d.

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This thesis describes the preparation of acyclic, macrocyclic and interlocked receptors for the recognition of anions in competitive organic and aqueous solvent media. Chapter One introduces the field of anion supramolecular chemistry, with a particular focus on the non-covalent interactions used for anion recognition and the synthesis of mechanically interlocked molecules. Chapter Two discusses the preparation of halogen bonding and hydrogen bonding acyclic and interlocked pyridinium-based receptors. Investigations into their anion selectivity trends are undertaken using 1H NMR titration experiments. The anion sensing properties of analogous hosts containing a fluorescent quinolinium motif are also described. Chapter Three presents the synthesis of acyclic and macrocyclic receptors containing the dicationic 1,2-bis(pyridinium)ethane motif. Attempts towards the preparation of interlocked receptors containing the motif are also discussed. Chapter Four focuses on a series of water-soluble receptors based around functionalised a-cyclodextrins. Isothermal titration calorimetry experiments are used to investigate differences in the thermodynamics of anion binding to halogen bonding and hydrogen bonding analogues. Chapter Five details the preparation of a [2]rotaxane containing a Lewis acidic triarylborane motif. Investigations into its anion binding properties are conducted using multinuclear NMR and UV-visible spectroscopies. Chapter Six provides the experimental details and characterisation data for the compounds discussed in Chapters Two to Five. Protocols for the titration experiments conducted are also described. Full crystallographic data is provided in the Appendix.

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5

Chen, Xi. "Designing Acrylic Block Copolymers with Multiple Hydrogen Bonding or Multiple Ionic Bonding". Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/84961.

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The dynamic characteristics of hydrogen and ionic bonding contributes to the reversible properties of acrylic polymers, opening new avenues for designing materials with mechanical strength and processability. These non-covalent interactions function as physical crosslinks, which provide enhanced structural and mechanical integrity to acrylic block copolymers. The strong hydrogen bonding or ionic interaction also directs self-assembly to hierarchical microstructures, which enables many applications including thermoplastic elastomers and energy storage devices. Inspired by complementary hydrogen bonding interactions between nucleobase pairs in DNA, a series of bioinspired nucleobase-acrylate monomers such as adenine acrylate (AdA), thymine acrylate (ThA), cytosine acrylate (CyA) were designed, whose synthesis were afforded by aza-Michael addition. Among those nucleobases, cytosine arises as a unique category. It is not only able to self-associate via weak hydrogen bonds, but also forms quadruple hydrogen-bond bearing units (ureido-cytosine) when functionalized with isocyanates. Reversible addition-fragmentation chain transfer polymerization (RAFT) yielded acrylic ABA triblock copolymers with CyA external hard blocks. A subsequent post-functionalization using hexyl-isocyanate generated the corresponding ureido-cytosine acrylate(UCyA)-containing triblock copolymers. The self-complementary quadruple hydrogen bonding in the UCyA polymers achieved a broader service iii temperature window, while the alkyl chain ends of UCyA units allowed tunability of the mechanical strength to apply as thermoplastic elastomers. In addition, quadruple hydrogen bonding induced stronger propensity of self-assembly and denser packing of the polymers, which contributed to a well-defined ordered morphology and enhanced resistance to moisture uptake. A facile 2-step synthesis provided doubly-charged styrenic DABCO salt monomer(VBDC18BrCl) containing an octadecyl tail. RAFT polymerization allowed the preparation of DABCO ABA block copolymers with defined molecular weights and low polydispersity. Thermal analysis revealed a melting transition of the VBDC18BrCl block copolymer resulting from the side-chain crystallization of the long alkyl tail. Systematic mechanical comparisons between DABCO salt-containing copolymers and the corresponding singly-charged polymer controls demonstrated superior mechanical properties attributable to a stronger ionic interaction between the doubly-charged groups. Morphological characterizations revealed a well-ordered lamellar microstructure and a unique three-phase morphology of the DABCO block copolymers, which involve a soft phase, a hard phase, and an ionic aggregates domain dispersed within the hard domain.
Master of Science

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6

Rix, Douglas. "Bond strengths and fluoride release of modified glass ionomer and resin adhesives". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp01/MQ39873.pdf.

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7

Johnsen, Bernt Brønmo. "Adhesive bonding of aluminium". Doctoral thesis, Norwegian University of Science and Technology, Faculty of Engineering Science and Technology, 2004. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-515.

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In order to get approval of adhesive bonding as a reliable joining method in the automotive industry, a better understanding of the interfacial interactions between aluminium surfaces and adhesives is important. It is also important to get a better understanding of the degradation mechanisms of the bonded systems in humid environments, as humidity is known to have a detrimental effect. This work has been focused on an aluminium alloy and a one-component epoxy adhesive that are of particular interest to the automotive industry.

Pretreatment of the aluminium substrates before adhesive bonding is essential. However, the most successful pretreatment processes involve the use of hexavalent chromium, which will be banned from use within few years due to environmental considerations. Alternative pretreatments need to be developed. A literature study identified silanisation with GPS as a pretreatment method with the potential to obtain good durability. On the basis of research performed by SINTEF Materials Technology, AC anodising in hot phosphoric and sulphuric acid solutions were also identified as interesting pretreatment methods.

A modified version of the Boeing wedge test was used to determine the durability of adhesively bonded joints tested in hydrothermal environments. The joints were made of AA6060-T6 aluminium alloy and Betamate XD4600 epoxy adhesive. Both silane films and anodic oxides were investigated using reflection-absorption FT-IR spectroscopy. Other techniques of surface analysis were also used (SEM, TEM, WLI, XPS, ToF-SIMS and contact angle measurements).

The environmental durability of pretreated AA6060-T6 substrates was significantly improved after silanisation with GPS. The grit-blasting + GPS pretreatment process resulted in considerable higher durability then the chromic-sulphuric acid FPL-etch. The general understanding is that silanisation improves the durability through the formation of strong, covalent bonds between the aluminium surface and the adhesive. FT-IR spectroscopy strongly indicated that a chemical reaction took place between GPS films and amine curing agents. Particularly interesting was the reaction with dicyandiamide, which is a common curing agent in one-component epoxy adhesives. The amines also catalysed the condensation of SiOH groups, resulting in higher degree of SiOSi crosslink density in the siloxane films. However, chemical reaction is not necessary for improved durability. The hydrophobicity of the bonded surface is also an important factor. This effect has not been studies extensively earlier.

Exposure of GPS films to degrading environments showed that the silane desorbed from the surface in acidic solutions, but it was stable in alkaline solutions. The durability of adhesive joints was also reduced in acidic environments. The two models for the degradation of the silanised aluminium surface in acidic environments were proposed: hydrolysis of the siloxane network and corrosion of the underlying aluminium surface.

The environmental durability of substrates that were AC anodised in hot phosphoric and sulphuric acid solutions was good, almost as good as the well-established FPL + PAA pretreatment. DC anodising in sulphuric acid gave inferior durability. FT-IR spectroscopy showed that the anodic films formed in sulphuric acid contained significant amounts of sulphate. This can have a significant negative effect on the long-term properties of bonded joints. The anodic films released water during curing of the adhesive. The observations suggested that a transformation from the hydroxide to the oxide state took place.

Adhesive bonding in wet environment of substrates that were anodised in sulphuric acid had a negative effect on durability. The effect was more pronounced for DC anodised, than for AC anodised substrates. Bonding in wet environment also resulted in changed adhesive properties close to the oxide surface. Very little thixotropic agent was present in a ~200 nm wide region in the adhesive. This was explained by desorption of water from the oxide during curing of the adhesive.

Papers II, V and VI are reprinted with kind permission of Elsevier, sciencedirect.com.

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8

Joshua, Nilmini Sureka, University of Western Sydney y Faculty of Science and Technology. "Novel phosphate bonding composites". THESIS_FST_XXX_Joshua_N.xml, 1997. http://handle.uws.edu.au:8081/1959.7/282.

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A cement material has been developed that has a controllable set time, compressive strength of about 50 MPa and shrinkage of under 2% when heated to 960 degrees centigrade. The main compound of this material has been shown to be the potassium analogue of struvite, in which potassium ion is substituted for the ammonium ion. The cement is formed by reacting a slurry made with potassium carbonate and monoammonium phosphate with magnesium oxide. Ihe amount and rate of addition of water to the mixture is controlled to determine the set time. It has been demonstrated that this cement may be used as a matrix in conjunction with cenospheres or cellulose fibres to form a low density composite material, and with silica powder to form a high strength composite. As well as optimising the cement mix for maximum strength and minimum shrinkage, a variety of properties of the K-cement were investigated. It was found that long term exposure of the cement to the atmosphere does not result in the formation of magnesium carbonate, but long term exposure to saline solutions can result in the formation of dypingite on the surface. No effect on strength was observed as a consequence of the age of the slurry or the cement, within 1-2 weeks
Doctor of Philosophy (PhD)

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9

Joshua, Nilmini Sureka. "Novel phosphate bonding composites /". View thesis, 1997. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20030828.115030/index.html.

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10

Wang, Xiaowei. "Adhesive bonding of polypropylene". Thesis, University of Bristol, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.247559.

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11

Dray, A. E. "Diffusion bonding of aluminium". Thesis, University of Cambridge, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.382557.

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12

Crankshaw, Donald S. (Donald Shane) 1974. "Aligned GaAs pillar bonding". Thesis, Massachusetts Institute of Technology, 1998. http://hdl.handle.net/1721.1/46170.

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13

Tudryn, Carissa Debra 1978. "Characterization of anodic bonding". Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/27145.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering; and, (S.M.)--Massachusetts Institute of Technology, Dept. of Materials Science and Engineering, 2004.
Includes bibliographical references (p. 149-151).
Anodic bonding is a common process used in MicroElectroMechanical Systems (MEMS) device fabrication and packaging. Polycrystalline chemical vapor deposited (CVD) silicon carbide (SiC) is emerging as a new MEMS device and packaging material because of its excellent material properties including high strength, hardness, and thermal conductivity. An alternative, low temperature glass to CVD SiC anodic bonding process is required in order to prevent gold tin braze stress relaxation. A novel process recipe, requiring a SiC RMS surface roughness of 45nm, was developed for anodically bonding CVD SiC to bulk and thin-film, lapped Pyrex[TM] and Hoya SD-2[TM] glass substrates. The bond quality, residual curvature, and microstructured interfacial features for CVD SiC anodic bonding were shown to be comparable to single crystal silicon (Si) anodic bonding. The Plaza Test specimen, invented by Plaza et al., was used to assess bulk and thin-film, lapped glass bond quality. A two-part contact/bonding model was used to predict the contact and bonding of the Plaza Test structures. Surface contact was predicted by a parallel plate capacitor pull-in model after the voltage was applied, and linear elastic fracture mechanics (FEA) modeling predicted the toughness or work-of-adhesion of the bonded surfaces after the formation of a permanent silicon dioxide bond. The role of the voltage, structure geometry, work of adhesion, and materials used in the model predicted that the bonding mechanism limited the total number of structures that remained bonded. thin-film, lapped glass bond quality improved when increasing the voltage and time. The calculated, experimental, and modeled thermoelastic curvatures were minimal, indicating low residual stress
(cont.) between the bonded materials. Finally, microscopy and elemental analysis showed distinct differences in elemental depletion band(s) of bulk Pyrex[TM] and Hoya SD-2[TM] glasses bonded to Si, and in interfacial bonding between Pyrex[TM] and CVD SiC compared to Pyrex[TM] and Si. More elements in the glass network are identified as participating in the depletion layer process than identified in previous studies. Overall, the process recipes, modeling, experimental work, and chemical analysis of glass to CVD SiC anodic bonding showed that CVD SiC can be bonded successfully and be a promising packaging material.
by Carissa Debra Tudryn.
S.M.

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14

Chen, Xi. "Exploring Multiple Hydrogen Bonding and Ionic Bonding in the Design of Supramolecular Polymers". Diss., Virginia Tech, 2020. http://hdl.handle.net/10919/98729.

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Supramolecular polymers represent a family of polymeric materials that are held together with dynamic, noncovalent interactions. In contrast to conventional functional polymers that usually have high melt-viscosity due to their covalent nature and chain entanglement, supramolecular polymers combine excellent physical properties with low melt-viscosity, allowing for less energy-intensive processability and recyclability. Dynamic bonding with multiple binding sites, such as multiple hydrogen bonding or multiple ionic bonding, exhibits much stronger binding strength compared to the counterparts containing only a single binding site, thereby allowing for enhanced mechanical integrity to the polymers and facilitate self-assembly. This dissertation focuses on the design of novel supramolecular polymers building from the doubly-charged or quadruple hydrogen bonding (QHB) scaffolds utilizing chain-growth polymerization or step-growth polymerization, as well as elucidate the structure-property-morphology relationships of the polymers. A 2-step nucleophilic substitution reaction afforded a series of 1,4-diazabicyclo[2.2.2]octane (DABCO)-based styrenic monomers with two pairs of charged groups. An optimized 2-step reversible-addition-fragmentation chain-transfer (RAFT) polymerization synthesized ABA triblock thermoplastic elastomers (TPEs) with a low Tg poly (n-butyl acrylate) central block and a high Tg external charged blocks. Strong ionic interactions between doubly-charged units drove molecular self-assembly to form densely packed, hierarchical microstructures, which contributed to a robust, crosslinked physical network that allows the polymer to retain thermomechanical integrity until degradation. High-resolution single-crystal X-ray diffraction (SCXRD) coupled with powder X-ray diffraction (PXRD) further disclosed a detailed 3-D structural information of molecular arrangement and ion distribution within the charged phase through comparing DABCO-salt monomer single-crystal structure and the corresponding homopolymer XRD pattern. It was found that the physical properties of the DABCO-salt copolymers not only relied on their charge content and architectures but also dependent on their electrostatically-bonded counterions. The size and structure of the counterion determined the strength of dipole-dipole interaction, which significantly impact on thermal property, (thermo)mechanical performance, water affinity, and microstructure. A cytosine-functionalized monomer, cytosine acrylate (CyA), allowed the synthesis of acrylic ABA triblock TPEs with pendant nucleobase moieties in the external blocks and a low Tg central polymer matrix through RAFT polymerization. Post-functionalization of cytosine (Cyt) bidentate hydrogen bonding sites with alkyl isocyanate, allowed the formation of ureido-cytosine (UCyt) groups in the external block that were readily dimerized through QHB interactions. The UCyt units in the external block enhanced mechanical strength and induced stronger phase-separation of the block copolymers compared to the corresponding Cyt-containing TPE analogs. Facile conventional free-radical polymerization using CyA and subsequent post-functionalization enabled accessibility to random copolymers containing pendant UCyt QHB moieties in the soft polymer matrix. The synergy of the flexible polymer matrix and the dynamic character of QHB groups contributed to the ultra-high elasticity of the polymer and rapid self-healing properties. QHB interactions enabled efficient mechanical recovery upon deformation by facilitating elastic chain retraction to regenerate the original physical network. Finally, one-pot step-growth polymerization through chain extending a novel bis-Cyt monomer and a commercially available polyether diamine using a di-isocyanate extender afforded segmented polyurea series for extrusion additive manufacturing. The molecular design of the polyureas featured soft segments containing flexible polyether chain and a relatively weak urea hydrogen bonding sites in the soft segment and rigid UCyt hydrogen bonding groups in the hard segment. The reversible characteristics of QHB enabled low viscosity at the processing temperature while providing mechanical integrity after processing and reinforced bonding between the interlayers, which contributed to the remarkable strength, elasticity, toughness, and interlayer adhesion of the printed parts.
Doctor of Philosophy
This dissertation focuses on designing supramolecular thermoplastic elastomers containing strong noncovalent interactions, i.e., quadruple hydrogen bonds or double ionic bonds. Inspired from noncovalent interactions in our mother nature, a series of bio-inspired monomers functionalized with nucleobase or ionic units were synthesized through scalable reactions with minimal purification steps. Polymerization of the functional monomers through step-growth or chain-growth polymerization techniques affords a variety of supramolecular thermoplastic elastomers with well-defined structures and architectures. These thermoplastic elastomers comprise soft and hard constituents; the former contains low glass transition polymer chains that provide elasticity while the latter contains strong noncovalent units to impart mechanical strength. Varying the soft/hard component ratios enables polymers with tunable physical properties to address different needs. Systematic characterizations of these supramolecular polymers revealed their distinct properties from the polymers containing the covalent or weak noncovalent interactions and facilitate molecular-level understanding of the polymers. Generally, incorporating strong noncovalent interactions increases the temperature for polymer segmental motion and extends thermomechanical plateau windows. Additionally, the strong association strength of those non-covalent interactions promotes microphase separation and self-assembly, contributing to a high degree of structural ordering of the polymers. Moreover, the dynamic characteristics of the noncovalent interactions offer the polymers with reversible properties, which not only enables melt-processability and recyclability of the polymer but also contributes to a series of smart properties, including self-healing, shape-memory, and recoverability. Thus, the molecular design using supramolecular chemistry provides promising avenues to developing functional materials with enhanced mechanical properties, processability, and stimuli-responsiveness for emerging applications.

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15

Fritz, Mark A. Cassidy Daniel Thomas. "Die bonding of diode lasers /". *McMaster only, 2004.

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16

Toprak, Filiz. "Mine Reclamation Bonding And Regulation". Master's thesis, METU, 2004. http://etd.lib.metu.edu.tr/upload/12605509/index.pdf.

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Dereliction of land by mining activities within the broad range of dereliction caused by other industrial and human activities was examined. Special attention was paid to impacts, mitigation, and costs thereof. Mine reclamation was examined in detail with special reference to professional interpretations. Mine reclamation bonding was studied with reference to environmental management planning so as to contribute to a forthcoming regulation concerning exactly these matters by providing a detailed listing of mining operations to be geared toward mine reclamation in Turkey&rsquo
s conditions and by providing key concepts in the inception of a draft regulation concerning mine reclamation as part of the EU accession program.

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17

Edmonds, Hannah. "Interlaminar bonding in ultrasonic consolidation". Thesis, Loughborough University, 2012. https://dspace.lboro.ac.uk/2134/10999.

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Ultrasonic Consolidation (UC) is a solid state additive manufacturing process which fabricates three-dimensional objects by ultrasonically joining metal foils together, layer-bylayer, to form a solid part. A wide range of materials can be used to fabricate parts by UC and products with complex internal geometry can be generated by shaping the crosssection throughout the build using Computer Numerically Controlled (CNC) milling. As a result of its ability to embed various secondary materials and fibres in metal matrices, UC has emerged as a potential method of fabricating multi-functional materials and structures.

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18

Mitchell, John Blayney Owen. "Theoretical studies of hydrogen bonding". Thesis, University of Cambridge, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.358697.

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19

Haller, Lars Jonas Larsson. "Theoretical studies of actinyl bonding". Thesis, University College London (University of London), 2008. http://discovery.ucl.ac.uk/1444217/.

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This thesis involves the computational study of uranium, neptunium, plutonium, and americium complexes in aqueous and non-aqueous solution. It seeks answers to specific experimental questions, to provide additional information to experiments, and to make predictions that experimentalists can use to design or abstain from new experiments. The work mainly uses density functional theory, as this method shows good scaling with system size. This is important because actinides have a large number of electrons, and the ligands in this work are often very large. The family of compounds with the formula U02(H2O) (OH)m 2 ,7 ( +w=5) are studied, to investigate how the changing equatorial ligand field affects the uranyl ion as hydroxide ligands replace water ligands. The investigation involves uranyl stretching vibrations, orbital analysis, charge analysis, and bond orders. I evaluate how solvent models affect the geometry and uranyl stretching vibrations. The cis and trans isomers of the U02Cl2(Cy3PNH)2 and U02Cl2(Cy3PO)2 (Cy = cyclohexyl) exist in equilibrium, even though one expects the bulky phosphinimine and phosphine oxide ligands to show large repulsion in a cis configuration. It is unknown experimentally whether the trans or the cis isomer is the major species. N-donor ligands displace O-donor ligands, when added to solution of U02Cl2(Cy3PO)2, i.e. the N-donor ligands form stronger bonds to uranium than the O-donor ligands. I investigate which isomer is the major species, and explain why the cis isomer exists at all. The origin of the stronger N-donor ligand bonds is studied by orbital analysis, energy decomposition, and electron densities. This study is extended to include all halide ligands, and uranium is substituted by neptunium, plutonium, and americium. I use the concepts of electron localisation and electron density differences on the systems above, to further study the actinyl axial and equatorial bonding in greater detail. I compare this analysis with the results from more traditional methods, e.g. charge analysis. I also investigate if it is possible to form stable c/s-uranyl compounds and neptunyl complexes with cation-cation interactions.

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20

Mondal, Raju. "Systematic studies of hydrogen bonding". Thesis, Durham University, 2004. http://etheses.dur.ac.uk/2986/.

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This thesis deals with wider application and implications of the hydrogen bond in crystal engineering studies and beyond; in addition, it also highlights the Cambridge Structural Database (CSD) as the potential knowledge-mine for inorganic chemists. The content of this thesis covers mainly three areas, viz, the role of hydrogen bonding in crystal engineering studies, the bridging between mainstream crystal engineering studies and solvates via hydrogen bond, and CSD studies on metal coordination spheres. Chapter 2 deals with crystal structure prediction through understanding the driving forces for forming supramolecular synthons and some rare supramolecular networks (Carbomndum III). With the help of a series of supraminols we attempt to identify the underlying reason for forming P-As networks. Chapter 3 covers the much debated topic of acceptor capabilities of organic halogens and consequently, how the so-called illusory hydrogen bond involving an organic halogen as an acceptor can explain a complex topic like synthon change-over, in a perfectly comprehensible manner. The aim of the Chapters 4 to 6 is to bring two separate fields, "crystal engineering" and "solvates" closer via a common root, like hydrogen bonding. The serendipitous host molecules are part of our crystal engineering studies, yet they form solvates due to less than optimum hydrogen bonding in their respective crystal structures. Alongside some usual solvates, in an unconventional way, different amines with varying steric, strain and donor hydrogen atoms were used. Different geometrical as well as crystallographical aspects and their explicit role in synthon selection has also been discussed. In Chapter 7, geometrical distortions of three-coordinate metal complexes in the crystal structures in the CSD have been analysed using symmetry modified Principal Component Analysis (PCA). Results shows that 90% of three coordinate species are accounted for by the five elements Cu, Ag, Hg, Au and Zn. Among the three major types of geometries, trigonal planar dominates the data sets, with smaller contribution for Y- and T-shaped structure. For Hg complexes, a possible reaction pathway for ligand addition reaction to two-coordinate linear complexes via T-shaped geometries leading to trigonal planar is discussed in detail. The background information and an overview of the experiments are discussed in the Introductory Chapter.

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21

Sagar, Rajeeve. "Self-assembly via hydrogen bonding". Thesis, University of Warwick, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.247352.

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22

Maddrell, Ewan Robert. "Diffusion bonding of aluminium alloys". Thesis, University of Cambridge, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.317935.

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23

Stenhouse, Henry G. "Direct bonding dissimilar optical materials". Thesis, University of Southampton, 2018. https://eprints.soton.ac.uk/420653/.

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This thesis presents the work conducted during this project on direct bonding of dissimilar optical materials at the Optoelectronics Research Centre, University of Southampton. It covers the history and background of the art, before progressing to the development of unique bonding processes used during the research detailed. During this project, direct bonding using chemical and plasma activation is successfully conducted on both amorphous and crystalline materials. Bonding of borosilicate glass is demonstrated in the production of planar structured fibre preforms to be caned. Development of Nd:YAG to sapphire bonds is reported, producing bonds of remarkable resilience, capable of surviving dicing and polishing procedures. Zinc selenide to diamond and sapphire bonding is presented using a plasma activated approach along with investigation of the resulting bond’s limits, demonstrating the heat spreading benefits of a bonded diamond layer.

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24

Judge, Benjamin Michael. "Thermoplastic bonding of microfluidic substrates". Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/78165.

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Thesis (M. Eng.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2012.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 103-108).
The assembly of microfluidic components for lab on a chip (LOC) applications that are manufactured from commodity thermoplastics is challenging. A survey of plastic welding techniques validates that contour transmission laser welding is the most viable and commercially demonstrated option for flexibility and sensitive microfluidic tolerances. However, understanding laser energy transmission and absorption phenomenon further complicates analyzing microfluidic thermoplastic welding, since the instantaneous material properties vary with both temperature and pressure. Thermoplastic welding has steep thermal gradients due to high thermal resistances, resulting in asymmetric heat affected zones (HAZ). Welding fixture sensitivities may be engineered to tune the weld energy required and a desired HAZ bias to reduce microfluidic channel deformation. Energy imparted by resistively heating thin implants can be easily measured and observed. Resistive heating of implants was demonstrated as a low energy, parallel, and feasible microfluidic welding assembly process. Lessons from implant heating can be applied to more complicated but analogous processes.
by Benjamin Michael Judge.
M.Eng.

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25

Van, Helvoort Antonius Theodorus Johannes. "Microstructural characterisation of electrostatic bonding". Thesis, University of Cambridge, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.619583.

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26

Cristescu, Carmen. "Self-bonding of beech veneers". Doctoral thesis, Luleå tekniska universitet, Träteknologi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-18315.

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This thesis presents studies on the self-bonding of veneers, and investigations into the properties of boards obtained by hot-pressing beech veneers without adhesives. The raw material is pressed at temperatures from 200 to 250ºC, at pressures from 4 to 6 MPa and pressing times from 240 to 360 s. The hot-pressing of five layers of veneers results in a self-bonded, compressed, densified board, darker than the raw material. The manufacturing process was optimised using a statistical analysis, the response surface experimental design method. The input factors were the pressing parameters and the output factors were characteristics of the product, the raw material properties being kept constant. The results showed correlations between the pressing parameters, especially temperature, as input data and the physical and mechanical properties as responses. Resistance to water absorption and swelling as well as shear strength, bending strength, and hardness were all enhanced by more severe pressing conditions. All the samples pressed at 250ºC became water-resistant while samples pressed at 200ºC delaminated rapidly in water. It was found that the colour of the edges can be used as an indication of the hardness. Chemical investigations were performed on samples taken from veneers (raw material), bond-lines and inner parts of pressed veneer. A High-Performance Liquid Chromatography (HPLC) analysis was used to detect and compare the levels of water-soluble monosaccharides (glucose and fructose) in the veneer before pressing and the levels of 5-hydroxymethyl-furfural (HMF) and furfural in boards. From the results obtained in this thesis it is suggested, that besides other degraded compounds of hemicelluloses, the monosaccharides were transformed into hydroxymethyl-furfural during hot-pressing that could further participate in forming new browning compounds that are related to the bonding phenomenon. The UV spectroscopic analysis to evaluate the content of water-soluble phenols showed that the bond-line had a higher amount of conjugated phenols than the inner veneer suggesting a migration of degraded lignin towards the veneer surfaces during pressing. A CP/MAS 13C NMR study on the solid material showed that the presence of β-ether structures and methoxyl groups in lignin was higher in the bond-line, supporting the hypothesis of a migration of lignin and possibly a condensation reaction occurring at higher temperatures, explaining the water-resistance property acquired by the boards.In a comparative study, oxidative activation with hydrogen peroxide and ferrous sulfate as a catalyst was performed before pressing. Boards made from beech veneer subjected to the pre-treatment step showed a greater mass loss, a lower thickness swelling but also a somewhat lower shear strength. For beech veneers such an oxidative pre-treatment step could be used to gain water-resistant boards pressed at lower pressing temperatures or shorter times than those needed to bond untreated veneers. Scots pine veneers were found to be less suitable for self-bonding than beech veneers. Boards of Scots pine hot-pressed without the oxidative pre-treatment delaminated in water, whereas, under the same pressing conditions, boards made from pre-treated veneers showed a water-resistant bond-line.

Godkänd; 2015; 20150825 (carmen); Nedanstående person kommer att disputera för avläggande av teknologie doktorsexamen. Namn: Carmen Cristescu Ämne: Träteknik/Wood Technology Avhandling: Self-Bonding of Beech Veneer Opponent: Professor Mark Hughes, Department of Forest Products Technology, Aalto School of Chemical Technology, Aalto University, Helsingfors, Finland Ordförande: Professor Dick Sandberg, Avd för träteknologi, Institutionen för teknikvetenskap och matematik, Luleå tekniska universitet, Skellefteå Tid: Onsdag 23 september 2015, kl 10.00 Plats: Luleå tekniska universitet, Hörsal A i Skellefteå

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27

Norris, Paul Richard. "Studies in metal-ligand bonding". Thesis, University of Surrey, 1996. http://epubs.surrey.ac.uk/844071/.

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The work in this thesis centres around direct equilibrium studies on the only two "soft" metal ions of the first row transition metals, low-spin d6 FeII and CuI, in relation to the linear free energy relationship given below. logK = a.pK + b. It is shown that solid Na3[Fe(CN)5(NH3)], which hydrolyses rapidly in solution to give the unstable [Fe(CN)5(OH2)]3- complex, can be dissolved in 0.1 mol dm-3 aqueous acetonitrile to give the much more stable complex [Fe(CN)5(MeCN)]3- (log K MeCN = 2.6 at 25°C, I= 0.1 mol dm-3). This more stable complex can then be used as the starting point for determining equilibrium constants for ligand substitution (of MeCN, and thus indirectly of H2O) on the "soft" low-spin d6 FeII ion under equilibrium conditions and over a wide range of pH (3 to 13 at least). Over 30 equilibrium constants are determined by uv-vis spectrophotometry for a number of nitrogenous bases (from four different families; RNH2, imidazoles, pyridines and RCN), with additional data determined for a series of sulphur containing ligands, which show that RS-, RCOS-, thiourea and RSH all form a single family. The linear free energy relationship is verified for each family of ligands studied, and in every case the value of a is shown to be ca 0, i.e. the equilibrium constant is apparently independent of the ligand basicity in both families of a-only and potential pi-acceptor ligands. Similar data are obtained for the water soluble porphyrin, FeII MP-8 in 20% aqueous methanol, which also show a ~ 0 for three families (RNH2, imidazole and pyridines). This establishes that a near zero value of a to be characteristic of the low-spin FeII ion. The alpha-effect and the steric effect are also studied with both FeII complexes. A method is also described in which the values of a can be semi-quantitatively determined for the "soft" CuI ion, by equilibration of solid CuCl in a 1 mol dm-3 aqueous solution of the ligand for one hour (25°C, pH 12, I= 0.1 mol dm-3) under hydrogen. Simple conversion to the CuII(EDTA) complex, after filtration, provides a suitable method for determining the concentration of copper solubilised after equilibration. Values of log [Cu]N are determined for about 15 nitrogenous bases (as a means of indirectly comparing the N-bases on the same basis), with a calpha 0 found for the three families studied (RNH2, imidazoles and pyridines). A coordination number of 2 is found for imidazole, and assumed throughout. This work provides the first detailed study of either of the "soft" first row transition metal ions, demonstrating that a is calpha 0 in both cases (cf other d6 and d10 ions). Data are related to published work on various d6 and d10 ions, and a remarkable similarity between the behaviour of the two is demonstrated. The data are, in turn, inversely correlated to the known gas-phase d-s promotion energies.

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28

Church, William Travis. "Laser Activated Bonding of Wood". Thesis, Virginia Tech, 2010. http://hdl.handle.net/10919/76888.

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It was found that laser modified wood surfaces can be bonded together to create a wood composite without the need of any additive. This bonding method removes the need of applying adhesive, potentially lowers cost, and eliminates off gassing of petroleum resins, creating a wood product with many eco-friendly attributes. This body of work outlines a) initial chemical analysis of the laser modified surface b) its bond strength and c) the optimization of factors that control the strength of the bond. Surface chemical analysis on laser modified wood was conducted using photo acoustic Fourier transform infrared spectroscopy (PA-FTIR) and X-Ray photoelectron spectroscopy (XPS). Light microscopy and scanning electron microscopy were utilized for surface topology analysis.Differential scanning calorimetry (DSC) quantified the thermal properties of the modified wood surface. Screening of multiple factors that would contribute to surface modification and adhesion was performed utilizing mechanical testing. Optimization of significant factors that affect bond strength was determined statistically utilizing a design of experiment approach. Chemical analysis of the laser modified surface revealed changes in the carbonyl and aromatic regions indicating modification of the hemicellulose and lignin components, intensifying with increasing laser modification.The C1/C2 ratios found via XPS revealed that one or more of the following is occurring: more extractives have moved to the surface, condensation reactions among lignin units, and the loss of methoxy and breakage of aryl ether linkages occurred.Microscopy images showed color changes to a darker caramel color with a smoothing of surface topology, suggesting the occurrence of the softening and/or melting of wood polymers. DSC verified chemical and/or physical changes in the wood with the modified material now having a glass transition temperature between 130-150°C.DOE found that laser parameters (power and focus) as well as hot press parameters (temperature and pressure) were significant in optimizing the bond. The impact of the study is the first documentation of the ability to laser modifies wood surfaces and subsequently bond them together. The ability of the wood polymers at the surface to undergo flow at elevated temperature is implicated in the adhesion mechanism of the laser modified wood.
Master of Science

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29

Scott, Tianeka S. "Understanding Hydrogen Bonding in Photoenolization". University of Cincinnati / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1378196534.

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30

Thote, Amol Janardan Gupta Ram B. "Molecular bonding in product engineering". Auburn, Ala., 2005. http://hdl.handle.net/10415/1275.

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31

McAdon, Mark Herbert Goddard William A. "New concepts of metallic bonding". Diss., Pasadena, Calif. : California Institute of Technology, 1988. http://resolver.caltech.edu/CaltechTHESIS:10302009-113153689.

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Thesis (Ph. D.)--California Institute of Technology, 1988. UM #88-03,406.
Advisor names found in the Acknowledgments pages of the thesis. Title from home page. Viewed 01/20/2010. Includes bibliographical references.

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32

Fiore, Daniel F. "High strength bonding of sapphire". Link to electronic thesis, 2002. http://www.wpi.edu/Pubs/ETD/Available/etd-0829102-155924.

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33

Stross, Alexander. "Synthetic H-bonding information oligomers". Thesis, University of Sheffield, 2016. http://etheses.whiterose.ac.uk/12365/.

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The nucleic acids contain chemical information in the form of a sequence of bases. This information content is expressed through sequence selective duplex formation and template directed synthesis. To date, the only programmable artificial information molecules that can truly rival the nucleic acids, in terms of their function, are structurally very similar to the nucleic acids. This thesis describes a synthetic approach to duplex forming hydrogen bonding oligomers that contain information in the form of a sequence of H-bond donor and acceptor groups, in the pursuit of a programmable material that is orthogonal to the nucleic acids. Chapter 1 is a literature review of natural and synthetic information molecules and their applications in nanotechnology, including an overview of the structurally reengineered versions of the nucleic acids, foldamers, template polymerisation and synthetic duplexes. The review highlights the absence of totally synthetic information oligomers, that are orthogonal to the nucleic acids, and Chapter 2 sets out the aims of this thesis, which is to address this gap. Chapter 3 describes the synthesis of oligomers equipped with phenol H-bond donors and phosphine oxide H-bond acceptors. Through cooperative H-bond formation, these oligomers form double stranded complexes, which were characterised by NMR titrations and thermal denaturation experiments. For each additional H-bond there is an order of magnitude increase in association constant. In Chapter 4 it is demonstrated that the modular design for the oligomers in Chapter 3 represents a general strategy to synthetic information oligomers. Two new classes of H-bond acceptor oligomer were synthesised, bearing pyridine and pyridine N-oxide groups. Both these systems also exhibit cooperative duplex formation with H-bond donor oligomers, which were characterised by NMR titration. Chapter 5 examines the ability of mixed sequence 3-mers formed of H-bond donors (phenol) and H-bond acceptors (pyridine N-oxide) to form duplexes in a sequence selective manner. All 8 combinations of donor and acceptor were synthesised, and NMR titrations were used to measure the association constants for each pairwise combination of oligomers. Sequence matched duplexes generally have the highest association constants, but there are some anomalies.

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34

Arman, Hadi D. "Strategies for expanding the halogen bonding periodic table and designing complementary halogen/hydrogen bonding synthons". Connect to this title online, 2008. http://etd.lib.clemson.edu/documents/1219848304/.

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35

Taber, Keith. "Understanding chemical bonding : the development of A level students understanding of the concept of chemical bonding". Thesis, Roehampton University, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.246174.

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36

Bende, David. "Chemical Bonding Models and Their Implications for Bonding-Property Relations in MgAgAs-Type and Related Compounds". Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2016. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-201406.

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In this work, chemical bonding models are developed and extended by the aid of the quantum-chemical position-space analysis. The chemical bonding models are then utilized to rationalize and predict the structure and conducting properties of MgAgAs-type and other intermetallic compounds. Additionally, new position-space bonding indicators are developed.

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37

Kodokian, George-Kevork. "Adhesive bonding of thermoplastic fibre-composites". Thesis, Imperial College London, 1989. http://hdl.handle.net/10044/1/8815.

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38

Howard, Daryl L. y n/a. "Hydrogen bonding in the near infrared". University of Otago. Department of Chemistry, 2006. http://adt.otago.ac.nz./public/adt-NZDU20060823.150321.

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OH-stretching spectra of various vapour phase species were recorded to investigate hydrogen bonding. The species studied include 1,2-ethanediol, 1,3-propanediol, 1,4-butanediol, acetylacetone, hexafluoroacetylacetone and the complex formed in the heterogeneous mixture of methanol and trimethylamine. The spectra range from the infrared, near infrared to visible wavelengths. The main focus of this study is in the near infrared region, in which the OH-stretching overtones are dominant. The near infrared and visible spectrum of formic acid has been recorded to investigate coupling across bonds, specifically a resonance occurring between OH- and CH-stretching vibrations. The same resonance was also observed in the spectrum of 1,2-ethanediol. The spectra of deuterated isotopomers of formic acid and 1,2-ethanediol were recorded to experimentally verify the resonance. The inherently weak nature of the vibrational overtone transitions required sensitive spectroscopic techniques to observe the spectra. The spectra were recorded with conventional long path length absorption spectroscopy and intracavity laser photoacoustic spectroscopy. Anharmonic oscillator local mode calculations of the OH-stretching transitions were performed to simulate the observed spectra. These calculations require calculation of potential energy surfaces and dipole moment functions. Simulated spectra obtained with highly correlated ab initio methods and large basis sets have yielded the best agreement with observation.

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39

Mills, Allison M. "Bonding patterns in new intermetallic antimonides". Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ60327.pdf.

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40

Biemond, Gerard Jan Eduard. "Hydrogen bonding in segmented block copolymers". Enschede : University of Twente, 2006. http://doc.utwente.nl/51102.

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41

Hung, Cheung-sing Tony. "Bonding of dental alloys to enamel". Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/HKUTO/record/B39558150.

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42

Yan, Ping. "Diffusion bonding of titanium aluminide (TiAl)". Thesis, University of Cambridge, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.241177.

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43

Taylor, Russell Alan. "Hydrogen bonding effects in homogeneous catalysis". Thesis, Imperial College London, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.500138.

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44

Thomson, Patrick. "Extremely strong contiguous hydrogen bonding arrays". Thesis, University of Edinburgh, 2013. http://hdl.handle.net/1842/7856.

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When multiple hydrogen bonds lie in-plane and parallel to each other in close proximity, they experience additional positive or negative secondary electrostatic interactions. When a pair of molecules are arranged such that every hydrogen bond acceptor is on one molecule and every hydrogen bond donor is on another, the positive secondary electrostatic interactions are maximised, and thus the association constant of the complex is enhanced. This thesis will present the development of a family of quadruple hydrogen bonded complexes containing only positive secondary interactions, which confers unprecedented stability. The complexes are sufficiently stable to maintain strong binding in polar solvents such as acetonitrile and can be switched “on” and “off” with acid and base. They will be developed into synthons for acid-base responsive supramolecular recognition, for use in stimuli-responsive supramolecular polymers and gelators.

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45

孔祥陞 y Cheung-sing Tony Hung. "Bonding of dental alloys to enamel". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B39558150.

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46

Ekambaram, Manikandan. "Aspects of solvents in dentine bonding". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2015. http://hdl.handle.net/10722/208591.

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Degradation starts at the resin-dentine bonded interfaces within a few months’ of bonding. There are two major causes of degradation of the bonded interfaces over time. The simplified dental adhesives that are routinely used in the contemporary clinical dental practice are extremely hydrophilic and are prone to water sorption, leading to hydrolytic degradation. Dentine matrix-bound metalloproteinases (MMPs) and cysteine cathepsins (CCs) are proteolytic enzymes that have been shown to degrade the uninfiltrated demineralized collagen at the bottom of the hybrid layer. Ethanol-wet bonding (EWB) with hydrophobic adhesive has been proven to improve the longevity of resin-dentine bonds in vitro. Chlorhexidine (CHX) treatment of demineralized dentine before bonding with adhesive resin has been shown to preserve resin-dentine bond durability in vivo and in vitro by inhibition of dentine matrixbound MMPs and CCs. However, it is not known whether simultaneous application of CHX and EWB would have any interactional effect on stability of resin-dentine bonds. 1-Ethyl-3-[3-dimethylaminopropyl] carbodiimide hydrochloride (EDC), both a dentine collagen cross-linker and a MMP inhibitor, has been shown to preserve dentine bond durability in vitro. However, both EDC and CHX are prepared in aqueous solutions using water as a solvent for application. The MMPs are hydrolases and the presence of residual water in the demineralized dentine following EDC and CHX applications will enhance dentine bond degradation. The general aims of this thesis were to investigate the effects of solvents in resindentine bonding, in particular the role of solvents in the enhancement of resin-dentine bond durability. In the earlier part of this thesis, the adjunctive application of 2% CHX with EWB using the simplified dehydration protocol for 60 s was examined as a bonding strategy to preserve dentine bond durability to sound and caries-affected dentine. The adjunctive application of EWB and CHX preserved bond durability of hydrophobic adhesive to both sound and caries-affected dentine after 12 months’ ageing. The same bonding strategy was applied to preserve the bond durability of luting fibre post to radicular dentine. However, the addition of 2% CHX to EWB did not further improve bond durability of hydrophobic adhesive to radicular dentine, when compared to EWB alone. In the later part of this thesis, the role of the solvents (commonly used in commercial dentine adhesives) in the enhancement of dentine bond preservation potential by CHX and EDC were assessed. The incorporation of 2% CHX in ethanol showed greater inhibitory effect on matrix-bound proteases than 2% CHX in water. Conversely, the use of acetone as a solvent for EDC also enhanced its dentine collagen cross-linking potential. The dentine collagen cross-linked by EDC in acetone was more resistant to enzymatic degradation. Within the limitations of this thesis, it could be concluded that solvents play a significant role in the enhancement of dentine bond durability. In general, ethanol and acetone are better than water for the preservation of dentine bond durability.
published_or_final_version
Dentistry
Doctoral
Doctor of Philosophy

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47

Critchlow, Gary W. "Pretreatments for metal-to-metal bonding". Thesis, Loughborough University, 1997. https://dspace.lboro.ac.uk/2134/7525.

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48

Hassani, Seyed Khosrow Seyed. "Isostatic bonding of pressed ceramic materials". Thesis, Queen's University Belfast, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334709.

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49

Trewin, Abbie. "Bonding at the carbon-metal interface". Thesis, University of Liverpool, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.428221.

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50

Locke, Christopher John. "Competitive hydrogen bonding in polymeric systems". Thesis, University of York, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.259805.

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Tesis sobre el tema "Bonding"

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