Academic literature on the topic 'Bonding efficiency function'

This study analyzed the mechanism underlying the effect of the bonding current on the bonding interface during anodic bonding on the basis of the anodic bonding of PEG (polyethylene glycol)-based encapsulation materials and Al. By establishing an equivalent electrical model, the effects of various electrical parameters on the dynamic performance of the bonding current were evaluated, and the change law of the bonding current transfer function was analyzed. By examining the gap deformation model, the conditions for contact between the interface gaps and the bonding current pair were determined, and the influence law of the gap deformation of the bonding interface was derived. By assessing the effect of the bonding current on the ionic behavior, we found that the larger the bonding current, the greater the number of activated mobile ions in the bonding material and the higher the field strength in the cation depletion area. From the anodic bonding experiments, it was found that increasing the bonding voltage can increase the peak current and improve the bonding efficiency. The SEM image after bonding shows that the bonding interface had no obvious defects; the higher bonding voltage can result in a thicker bonding layer.

Functionalized multi-wall carbon nanotubes (MWCNTs) have been embedded in a rubber-toughened epoxy formulation in order to explore the possibility to impart an auto-repair function to the epoxy matrix. The nanofiller has been covalently functionalized with hydrogen bonding moieties able to act as donor and acceptor of hydrogen bondings. Healing efficiencies have been evaluated for nano charged epoxy formulations at a loading of 0.5% wt/wt of functionalized MWCNTs bearing barbituric acid and thymine-based ligands. For both the performed functionalizations, a self-healing efficiency higher than 50% has been found. Dynamic Mechanical Analysis (DMA) highlights that the inclusion of nanofiller increases the storage moduli. Furthermore, DMA analysis evidences the presence of a phase characterized by a greater mobility of the epoxy chains, which promotes the activation of self-healing mechanisms.

As an ideal layout scheme for launch vehicle, bearing co-bulkhead tank can improve the slenderness ratio of launch vehicle, reduce structure weight and increase structure efficiency. In this paper, a novel cryogenic tank co-bulkhead was fabricated by vacuum assisted resin transfer molding (VARTM) process. Consisting of LD10 alloy and polymethacrylimide (PMI) foam-sandwich, the new cryogenic tank co-bulkhead was designed with variable-thickness, hemi-ellipsoid structure, thermal insulation and bearing function. Fundamental temperature distribution, thermal stress and low-temperature load sensitivity of the foam-sandwich co-bulkhead were also assessed by finite element analysis and environment tests in simulated service environment. The results showed that the analog values highly agreed with the test results, and thermal insulation and bearing function of the foam-sandwich co-bulkhead could satisfy the design requirement, which proved the reliability of bonding quality and feasibility of the bonding technique.

Geogrids are used as reinforcement materials for soil foundation structure in the geotechnical applications. Also, geogrids have the excellent tensile strength and modulus and therefore, geogrids can show the good reinforcement function within the soil foundation structure that the loads are concentrated. However, geogrids don't have the excellent efficiency to control the migration and loss of fine soil particles to be passed due to the large apertures (opening size).The new concept of reinforced geotextile composites, which can show both functions of reinforcement and separation/drainage and was manufactured by combining nonwoven geotextiiles and geogrid or geonetusing adhesive or thermal bonding process. Geotextile-Geonet Composites compose of geotextile-geonet-geotextilesandwich use for separation and filtration functions. Hence the objective of this study is to manufacture geocomposite for easy installation and better stability of sandwich material in soil condition. This geocomposites are evaluated for its performance.

This research news describes the construction of polymeric nanostructured composite film based on a variety of interactions, such as hydrophobic–hydrophilic effect, electrostatic interaction, hydrogen bonding, etc. The work focused on developing strategies to solve the basic problems in the area of ultrathin film research, such as stability, improving the interface quality, creating patterned interface, and techniques to construct nanolayered structure. With in-depth study of the relationship between the microscopic layered architecture and macroscopic function of supramolecular assemblies, it is anticipated that one could obtain miniature devices or machines of high efficiency through integration of the assembling process and device fabrication.

Purpose – This paper aims to solve the issue of target positioning in auto stiffener bonder (ASB) systems for flexible printed circuits. Design/methodology/approach – The proposed approach uses Phong’s bidirectional reflectance distribution function (BRDF) model to simulate the reflection of light off a target in ASB systems to predict the current pose of the target based on image brightness, update the template, decrease the initial errors in the template and narrow down the search range. Findings – The experimental results indicate that the proposed approach can predict the inclination angle of the target with precision, presenting angle prediction errors of less than three degrees. Furthermore, with larger inclined angles, the overall matching errors were less than 1.5 pixels. Comparisons with the unmodified matching algorithm revealed that the proposed approach resulted in 65 per cent less calculation time for the algorithm and 14 per cent higher overall work efficiency in the ASB system. Originality/value – The edge-based perspective shape matching algorithm was modified using the Phong BRDF model and enhanced algorithm efficiency with the target pose prediction method while ensuring the precision and robustness of the system. The proposed approach has high potential value and can be expanded to recognition systems for objects with varying inclination angles and highly reflective surfaces.

Polymorphism of crystals, crystal habit and crystal growth are important factors that must be controlled for any commercial crystallization process. Pharmaceuticals and agrochemicals are two of the most industrially-important, active-molecule systems for which the physical properties are strongly correlated to their crystal structure. While pharmaceuticals have attracted more academic interest to date, the market for agrochemicals is also very considerable, amounting to $15 bn annually. Given the potential significant toxicity of some agrochemicals, the ability to control physical properties such as solubility and dissolution rates, which depend on the crystal structure of the agrochemical itself, represents a way of optimizing the ratio between the amount of product used and its efficiency, improving its function and reducing its environmental impact. Hydrogen bonds play a crucial role in the spatial arrangement of the active molecules and the crystallization process. However, high accuracy and precision of the hydrogen atom positions can only be achieved through single crystal neutron diffraction (SND). SND experiments have been performed on three herbicides - isoproturon (IPU), pendimethalin (PDM), and diflufenican (DFF) - and the fungicide cyprodinil (CYP) [1][2]. All four structure refinements show a ten-time improvement in precision in the hydrogen atom positions compared to SXD with accurately determined nuclear positions. For cyprodinil, which crystallises as two polymorphs, A and B, differences in the hydrogen bonding network have been determined. Form A is governed by single, linear hydrogen bonds between two molecules, while the B form is characterized by the presence of dimers linked through pairs of hydrogen bonds, leading to a stable 8-membered ring. These differences in structure are reflected in the physical properties of the two polymorphs such as melting point and the observed slow inter-conversion that takes place during storage.

The prevalence of leaping across delphinids indicates it has an adaptive benefit. I examined leaping behaviour in dusky dolphins (Lagenorhynchus obscurus) according to signalling, social facilitation, and prey capture hypotheses. I quantified the effect of leaping on group behaviour and fission-fusion and the behavioural context of leaping. I observed dolphins in Admiralty Bay, New Zealand during 171 focal follows totalling 157 h. Data were analysed using generalized estimating equations. Clean leaping had a positive effect on party fission () and foraging behaviour (). Coordinated leaping caused a short-term wane in foraging behaviour () and had a positive effect on party fusion (). Noisy leaping had a negative effect on perpetuating resting and traveling cessation (both ). The signalling hypothesis was the most strongly supported. The social facilitation and prey capture hypotheses were moderately supported. Leaping may provide adaptive benefits such as reduced scramble competition, increased foraging efficiency, and social bonding.

Prestressed concrete structures have witnessed widespread use in building and infrastructure applications during the last two decades due to their high stiffness and strength indices. However, structural failures caused by the corrosion of steel reinforcing bars or strands have proliferated, opening the door for carbon fibre-reinforced polymer (CFRP) strands as an excellent alternative with high corrosion resistance. The bonding interaction between the CFRP strands and concrete is the fundamental parameter in shaping the structural behaviour of CFRP prestressed concrete structures. In this paper, the bonding behaviour between CFRP strands and concrete with grouting admixture is experimentally investigated based on three groups of standard pull-out tests. The bond strength of CFRP strands was systematically studied and compared against steel strands. The untreated CFRP strands exhibited an inefficient bonding strength with the grouting admixture, equivalent to only 5% compared to steel strands of the same diameter. Surface coating with epoxy quartz sand can significantly improve the anchoring efficiency of CFRP strands up to 14 times compared to the untreated strands, which is approximately as efficient as steel strands. Moreover, the bond–slip curves between CFRP strands and concrete were analysed and were found to be different compared to steel strands. Finally, this study proposed bond–slip constitutive models of CFRP strands with better applicability, using an exponentially damped sine function to fit the residual segment of the curve.

The X-ray structure of lactate dehydrogenase (LDH) shows the side-chain carboxylate group of Asp-143 to be buried in the hydrophobic interior of the enzyme, where it makes hydrogen-bonding interactions with both the side-chain hydroxyl group of Ser-273 and the main-chain amide group of His-195. This is an unusual environment for a carboxylate side-chain as hydrogen bonding normally occurs with water molecules at the surface of the protein. A charged hydrogen-bonding interaction in the interior of a protein would be expected to be much stronger than a similar interaction on the solvent-exposed exterior. In this respect the side-chain carboxylate group of Asp-143 appears to be important for maintaining tertiary structure by providing a common linkage point between three discontinuous elements of the secondary structure, alpha 1F, beta K and the beta-turn joining beta G and beta H. The contribution of the Asp-143 side-chain to the structure and function of Bacillus stearothermophilus LDH was assessed by creating a mutant enzyme containing Asn-143. The decreased thermal stability of both unactivated and fructose-1,6-diphosphate (Fru-1,6-P2)-activated forms of the mutant enzyme support a structural role for Asp-143. Furthermore, the difference in stability of the wild-type and mutant enzymes in guanidinium chloride suggested that the carboxylate group of Asp-143 contributes at least 22 kJ/mol to the conformational stability of the wild-type enzyme. However, there was no alteration in the amount of accessible tryptophan fluorescence in the mutant enzyme, indicating that the mutation caused a structural weakness rather than a gross conformational change. Comparison of the wild-type and mutant enzyme steady-state parameters for various 2-keto acid substrates showed the mutation to have a general effect on catalysis, with an average difference in binding energy of 11 kJ/mol for the transition-state complexes. The different effects of pH and Fru-1,6-P2 on the wild-type and mutant enzymes also confirmed a perturbation of the catalytic centre in the mutant enzyme. As the side-chain of Asp-143 is not sufficiently close to the active site to be directly involved in catalysis or substrate binding it is proposed that the effects on catalysis shown by the mutant enzyme are induced either by a structural change or by charge imbalance at the active site.(ABSTRACT TRUNCATED AT 400 WORDS)

Pour garantir la sécurité des vols dans des conditions de neige, les constructeurs d'aéronefs doivent démontrer que chaque moteur et son système d'admission d'air peuvent fonctionner sur toute la plage de puissance de vol dans des conditions de neigeuse. Cette étude fait partie d'un effort visant à développer des modèles pour l'accumulation de neige.Pour établir le cadre de départ de ce travail sur la modélisation du givrage de la neige, le chapitre 1 est consacré à une revue de la littérature organisée en trois parties. Dans la première partie, les différents processus de création de neige dans l'atmosphère sont détaillés afin de définir la neige qui sera étudiée ici. Dans une deuxième partie, une revue de la littérature sur la modélisation du givrage des cristaux de glace est réalisée et constitue le point de départ de ce travail du point de vue de la modélisation. Enfin, une troisième partie présente les moyens expérimentaux actuels pour mesurer les conditions de neige et les avantages et inconvénients associés.Dans le chapitre 2, nous étudions les modèles de traînée adaptés au cas des flocons de neige pour calculer les trajectoires des particules. Comme mentionné dans l'état de l'art, les modèles classiques développés pour les particules non-sphériques s'avèrent suffisamment précis pour les cristaux de glace. L'objectif est double. D'une part, il s'agit de vérifier que les modèles valables pour les cristaux de glace le sont également pour les flocons de neige, qui sont en fait des agrégats de particules, beaucoup plus grands et de forme géométrique complexe. D'autre part, les modèles de traînée proposés doivent être compatibles avec le type de données d'entrée. Par exemple, à la fin d'une campagne d'essais en vol, les particules ne peuvent être décrites qu'à l'aide d'images 2D, ce qui est loin d'une description 3D complète et détaillée du flocon de neige. Compte tenu du niveau de précision des données d'entrée utilisées pour décrire la particule, l'objectif de ce chapitre est de proposer des modèles de traînée basés sur une description géométrique simple et limitée des flocons de neige.Le chapitre 3 est l'équivalent du chapitre 2 pour l'adaptation des modèles de transfert de chaleur et de masse aux flocons de neige. Le processus de fusion d'un flocon de neige transporté par un flux d'air chaud est étudié. Une fois de plus, l'exigence est double. D'une part, il s'agit de vérifier si les modèles développés pour les cristaux de glace peuvent être facilement étendus au cas des flocons de neige. D'autre part, proposer des modèles pour lesquels la complexité des données d'entrée est compatible avec le niveau de précision des bases de données. Pour rappel, les descriptions 3D des flocons de neige sont rares et difficiles à obtenir. Dans de nombreux cas, une seule image 2D de la particule issue d'une campagne d'essais en vol est disponible. Dans ce chapitre, l'accent est mis sur la description de la densité apparente de la particule, et en particulier sur son évolution au cours du processus de fusion. En effet, la densité apparente peut varier considérablement, de quelques kg/m3 pour la particule sèche à 997 kg/m3 pour la gouttelette d'eau résultant du processus de fusion.A l'issue des chapitres 2 et 3, des modèles ont été proposés pour la trajectoire des paillettes et pour le suivi du processus de fusion. Il est ainsi possible d'estimer la localisation de l'impact et la quantité d'eau transportée par les flocons. L'étape physique suivante concerne l'accrétion des particules de neige. Les données expérimentales seront utilisées pour valider ou améliorer les modèles d'accrétion des cristaux de glace. A notre connaissance, aucune base de données traitant de l'accrétion de la neige dans des conditions aéronautiques n'a été mise à disposition jusqu'à présent dans la littérature. C'est dans cette optique que ce chapitre traite de la conception et de la réalisation de ces essais d'accrétion de neige
To ensure safe flight under snowy conditions, aircraft manufacturers must demonstrate that each engine and its air inlet system can operate throughout the flight power range of the engine (including idling) in both falling and blowing snow conditions. This study is part of an effort to develop models for snow accretion.To establish the starting framework of this work on the modeling of snow icing, Chapter 1 is dedicated to a literature review organized in three parts. In the first part, the different processes of snow creation in the atmosphere are detailed in order to define the snow that will be studied here. In a second part, a literature review on the modelling of ice crystals icing is conducted and constitutes the starting point of this work from the modeling point of view. Finally, a third part relates the current experimental means to measure the snow conditions and the associated advantages and disadvantages.In the chapter 2 we study drag models adapted to the case of snowflakes for calculating particle trajectories. As mentioned in the state of the art, the classical models developed for non-spherical particles are proving sufficiently accurate for ice crystals. The aim here is twofold. Firstly, to check that the models valid for ice crystals are still valid for snowflakes, which are in fact aggregates of particles, much larger and of complex geometric shape. Secondly, the drag models proposed must be compatible with the type of input data. For example, at the end of a flight test campaign, particles can only be described using 2D images, a far cry from a complete and detailed 3D description of the snowflake. In light of the level of accuracy of the input data used to describe the particle, the aim of this chapter is to propose drag models based on a simple and limited geometric description of snowflakes.The chapter 3 is the equivalent of Chap. 2 for adapting heat and mass transfer models for snowflakes. The melting process of a snowflake transported by a hot air flow is studied. Once again, the requirement is twofold. Firstly, to check whether the models developed for ice crystals can be easily extended to the case of snowflakes. Secondly, to propose models for which the complexity of the input data is compatible with the level of accuracy of the databases. As a reminder, 3D descriptions of snowflakes are scarce and difficult to obtain. In many cases, a single 2D image of the particle from a flight test campaign is available. In this chapter, particular emphasis is placed on describing the particle's bulk density, and in particular its evolution during the melting process. In fact, bulk density can vary widely, from a few kg/m3 for the dry particle to 997 kg/m3 for the water droplet resulting from the melting process.At the end of the Chapters 2 and 3, models were proposed for the trajectory of the flakes and for monitoring the melting process. It is thus possible to estimate the location of the impact and the amount of water carried by the flakes. The next physical step concerns the accretion of snow particles. Experimental data will be used to validate or improve the ice crystal accretion models. To our knowledge, no database dealing with snow accretion under aeronautical conditions has been made available so far in the literature. It is in this concept that, this chapter deals with the design and the realization of such "snow" accretion tests. A first comparison with the numerical simulations of the ONERA icing code IGLOO2D will also be proposed

Local governments frequently network with other local governments or other entities for efficient or effective delivery of local services. Networks enable local governments to discover ways to address externalities and diseconomies of scale produced by political fragmentation, functional interconnection, and uneven distribution of knowledge and resources. Local government networking can be informal or formal and bilateral or multilateral, in the form of deliberative forums or mutual aid agreements. This chapter uses the institutional collective action framework to underscore the link between problems of coordination and credibility of commitment that local governments face as they seek self-organizing solutions and the bridging and bonding networks they create in response to these problems. It then reviews the current state of scholarship in local government networks (LGNs) and shows that much progress has been made in both egocentric and whole LGN studies. Finally, it highlights important areas needing attention to advance LGN scholarship.

Due to the ever-increasing need for production efficiency and reliability as well as cost saving, assembly industries have been looking for a better solution compared to current methodologies. It is critically important to know that there is a solution this industry had not paid much attention and can benefit a lot due to not only historical reason but also limited knowledge management or awareness. This chapter examines and qualifies the effect of a couple of special adhesive bonding solutions on various glass plate bonding applications at appliance industry using a total solution such as dispensing system and robot. The result clearly shows its benefit over current methodologies, and also as industry trend moves toward more exterior decoration for high-end image products, this chapter should contribute on glass bonding industry not only for faster production, better efficiency, less production space, and better reliability but also for lower manufacturing cost using special adhesive bonding solutions.

Organic corrosion inhibitors are preferred due to its environmental friendly and effectiveness at a wide range of temperatures. The efficiency of an organic inhibitor depends on the size of the organic molecule, aromaticity, type, and number of bonding atoms or groups in the molecule (either π or σ), nature and surface charge, the distribution of charge in the molecule, and type of aggressive media. The presence of polar functional groups with S, O, or N atoms in the molecule, heterocyclic compounds and pi electrons present in the molecule also increases the efficiency of these organic corrosion inhibitors. The use of computational chemistry such as density functional theory (DFT), molecular dynamic simulation (MD), Monte Carlo (MC) simulations, and quantitative structure-activity relationship (QSAR) modeling has been applied for study of corrosion inhibition properties of organic compounds. This chapter will explain about theoretical and computational study of organic compounds as corrosion inhibitors.

This chapter discusses the influence of technology on the tendencies of prehistoric societies and their attitude toward relationships in comparison to later cultures. How did technology affect hunter-gatherer forms of relationships? While most of today’s Western societies focus on the individual, the group stood at the center of hunter-gatherer society. This social structure allowed these societies to function efficiently in finding food and shelter. As survival stood at the center, the main aim of Relationships 1.0 was to procreate in safety, with some social and inter-group bonding goals also in play. Moreover, with no one living separately, the boundaries between couples became inconsequential. In this way, the nature of relationships (monogamous, sexually permissive, polyandrous, or polyamorous) was shaped by basic social structures driven by the technological means of finding food and acquiring shelter. The argument here is not of a direct and exclusive link between technological means and relationship formation, but rather that technological means triggered a chain of social circumstances, which, in turn, encouraged certain tendencies in pairing and bonding. In other words, relationships developed in light of the wider social organization and the means available to the people of Society 1.0.

Due to the increase in use of radiation energy in many industrial applications, radiation shielding has become a crucial topic in order to diminish its hazardous effects. Radiation shields can be of various weights depending on the materials from which they are produced and the area in which they are used. In this sense, polymer composites have taken attention by researchers because it is aimed to obtain shields with good processability, sufficient flexibility, low weight, and subsequent performance properties. Epoxy resin is one of the mostly used synthetic polymers as a matrix element in composite material production due to its improving characteristics by means of electrical insulation, chemical resistance, service life, bonding characteristic, and mechanical properties. Besides, epoxies have intermediate radiation shielding characteristics as well. By loading epoxy matrix with fibers and/or fillers having different radiation absorption rates or mechanical resistance properties, multifunctional shields can be produced to serve in numerous applications. This chapter focuses on radiation shielding efficiency of fiber-reinforced epoxy composites and the role of fillers and fiber-based materials on manufacturing of functional radiation shields.

The key aspects of the microscopic description of structurally inhomogeneous media are considered. This makes it possible to evaluate the macroscopic properties of stochastic multicomponent materials using statistical methods and distribution functions of local effective indicators and is important for predicting the behavior of structurally heterogeneous building materials under various conditions. It also allows us to develop new approaches to the creation and use of new materials in the future and their optimization for various applications. Studies of macroscopic and microscopic aspects of dislocations and strains in brick and mortar are described. The influence of these phenomena on the mechanical properties and strength of building structures made of masonry has been studied. Two main types of dislocations are considered - edge and screw, as well as the relationship with macroscopic deformations of the structure of stone materials. Using elasticity theory and brittle fracture mechanics, the mechanical behavior of masonry structures under different loading conditions is analyzed to establish the relationship between stress, strain and strength of masonry. Various ways of calculating the strength of elements and structures are also considered, taking into account the macroscopic and microscopic aspects of dislocations and deformations, and it is proposed to use the results obtained to predict the behavior of masonry structures as a result of the application of a load. The results of the study of the mechanism of dislocation propagation in masonry at the microscopic level are important research in the field of industrial and civil engineering. This will help to better understand the interaction of materials under external loading and optimize masonry installation processes to improve its strength and durability. Research and development in the construction and civil engineering industry is improving the design and efficiency of stone materials. Microscopic and macroscopic aspects of dislocations and deformations in masonry play an important role in increasing the strength and understanding the mechanical properties of building structures. The characteristic dimensions of the component sections of the masonry should be much larger than the molecular kinetic dimensions, but, at the same time, much smaller than the distances at which the averaged state parameters change noticeably. The main aspects of the influence of the microscopic properties of a heterogeneous medium on predicting the macroscopic properties of masonry are considered. Important for understanding and predicting the behavior of structurally inhomogeneous materials under different conditions is the assessment of the macroscopic properties of stochastic multicomponent materials using statistical methods and distribution functions of local effective indicators. Taking this into account makes it possible to develop new approaches to the design and optimization of building materials for various applications. Research into the mechanism of dislocation propagation in masonry provides valuable scientific basis for the development of more efficient installation methods and improved strength properties. This is an important contribution to the construction industry, helping to create stronger, more resilient and longer-lasting building structures. The propagation of dislocations is significantly influenced by the cementitious material, laying methods, and the shape and geometry of masonry elements. The optimization of these factors will reduce the risk of damage and improve the strength characteristics of structures, and, as a result, will lead to the creation of more effective methods for constructing and strengthening buildings and structures. The results described in this monograph allow the development of new materials with improved deformability and load adaptation. This may include the use of composite materials or modification of bonding materials to improve their strength properties. An important aspect is the development of methods for monitoring and diagnosing the condition of masonry. New methods based on the study of dislocations will make it possible to quickly identify damage and take measures to prevent or repair it, which contributes to the safety and stability of buildings.

In order to improve the possibility of successful bonding and performance of structures, the new method for multi-depth silicon etching is required. This paper aims to design and create a new method for one-time multi-depth silicon etching in manufacturing complex structures based on SiO2 masking layer. The core idea of this method is that: Firstly, all patterns are transferred into photo resist through photo etching; Then etch pattern will be transferred in the SiO2 masking layer by multi-time shallow etching with different time etching control; Finally, patterns will be transferred to the silicon wafer with uniform ratio based on the measured etching selectivity of SiO2-Si with one time. In the experiments, the process is completed in the silicon wafer with SiO2 masking layer whose thickness is elaborately designed. Firstly, the etching rate of SiO2 and the etching selectivity of SiO2-Si were measured accurately. Secondly, the shallow structure based on the designed structure, the etching rate of SiO2 and the etching selectivity of SiO2-Si is etched on the SiO2masking layer. The second step forms different thickness version of SiO2 masking layer. At last, the SiO2 masking layer is etched until final structure and consequently different depth of groove accomplish due to various thickness of SiO2 etched by previous step. The experimental results indicated that the new methods has at least three advantages compared to traditional method: That is faster efficiency, higher cleanness and more complex structure. Fast work efficiency owes to only SF6 etching rather than two gases of SF6 and C4F8 to reduce half of time. Also high cleanness comes from being not exposed to air and researchers directly. The largest benefit of new method may be that can create more complex structure for higher required machine design and for higher mechanical function. It is because that normal etching method could only build few different depth of grooves due to multi-process limitation and contrary to normal one, new method can create more different depth of groove. And more different depth of groove means that more complex structure can be designed.

Molecular imprinting is an emerging technology that allows to introduce nanostructured cavities into a polymer. In preparing molecular imprinted polymers (MIPs), the functional monomer(s) is first prearranged around the template molecule by specific interactions; the polymerisation is then carried out with a high percentage of cross-linking agent (which “freezes” the macromolecular network). Molecular mechanics and dynamics can be used to gain indications on the best monomers to be used in order to maximize interactions with the template. Once the polymerization reaction has been completed, the template is removed from the rigid three-dimensional network, leaving free recognition cavities available for the successive selective rebinding of the template itself. Precipitation polymerisation in dilute solutions involves the spontaneous formation of submicron scale polymer particles, which result suitable for recognition-rebinding application. Therapeutic applications: The recognition mechanism by MIPs relies mainly on the establishment of reversible hydrogen bonding interactions. It is clear that the efficiency of this mechanism is endangered in aqueous environments. MIPs working in water solutions are clearly of great interest in the medical and food industry and in sensor applications. We recently overcame these difficulties by the realisation of a system where cross-linked MI methylmethacrylate-methacrylic acid nanospheres where loaded on the surface or inside the matrix of porous membranes created by phase inversion. E.g. membranes were modified by adding cholesterol imprinted nanoparticles. Rebinding performances of nanoparticles modified membranes in buffer solution were tested showing a specific recognition of 14.09 mg of cholesterol/g of system (membrane and nanoparticles), indicating maintained binding capacity of supported particles as well. Tissue engineering: The engineering of functionalised polymeric structures for the study of cell activity is essential to the development of biological substitutes containing vital cells capable of regenerating or enhancing tissue function. Cells are organised within a complex matrix consisting of high molecular weight protein and polysaccharides known as the Extracellular Matrix (ECM). Two approaches are described to explore the possibility to provide scaffolds with specific and selective recognition of peptide sequences or proteins involved in cell adhesion mechanisms: one approach consists in the modification of porous structures with nanoparticles imprinted with aminoacid sequences (epitopes) of ECM proteins or transmembrane integrins, while the other consists in the combination of Soft Litography and Molecular Imprinting technologies (SOFT-MI). This technology allows to create imprinting nanocavities selective towards ECM proteins in microfabricated scaffolds, and in particular it permits to realise patterns with a well defined microscale geometry in polymethylmethacrylate (PMMA) scaffolds providing them with cell adhesion properties that were missing in the non-imprinted scaffold.

Abstract A novel type of Chemistry based Autonomous Inflow Control Devices (Chemical-AICDs or C-AICDs) is introduced with the capability of restricting unwanted fluids based on chemically altering the fluid path structure in response to surrounding fluids. These devices are completely viscosity and density independent and don't require any intervention for water shutoff, resulting in saving time and cost during life of well. We discuss design elements, optimization, testing and evaluation methods of a selected configuration of the C-AICD. C-AICD construction includes ported funnel and multi-core ball. As part of multi-core ball design, novel inorganic coating processes are synthesized and optimized to create multilayer coatings that have strong interlayer bonding to provide sealing integrity and controlled dissolution to facilitate uniform change of diametrical positions of the ball. The ported funnel design is optimized using Computer Aided Design and 3D printed to confirm fit-form with the multi-core ball at various operational positions. The C-AICD flow performance was evaluated by a custom flow calculator based on orifice theory. Initial Computational Fluid Dynamics simulations (CFD) was carried out on one configuration of the ICD assembly. This calculator will be calibrated through CFD and function tested in a flow loop to validate flow performance and compatibility with system. While advanced completion technology is created to enhance well performance, it is often more complex in design and field installation and comes at a higher cost than existing field-proven technologies. The revolutionary C-AICD design allows applications for oil production in fields while being sustainable, cost effective and efficient. The C-AICD incorporates a time and environment trigger selective water/oil dissolvable mechanism on thin coatings applied on a ball, formulating a mechanism for the world's first chemically configurable adaptive ICD. Novel methods and configurations to build a C-AICD using the dissolvable ball coatings concept packaged in a ported funnel are discussed. The time/environment dependent selective dissolution changes the diametrical position of the ball in the funnel changing flow port area available for inflow. Preliminary device efficiency and performance optimization of system was carried out through analytical flow calculation using physics based mathematical models. Study revealed the relationship between flow-rate, velocity, and pressure drop across C-AICD. This ensures a design standard for appropriate selection and sizing for efficient system performance. Individual elements like multi-core ball materials and coatings were optimized through careful synthesis and characterization. This paper presents design, analysis, and optimization roadmap philosophy of a new cost-effective C-AICD that discriminates oil versus water with time/environment dependent selective dissolution of coatings on a ball. The process alters the diametrical position of the ball in the flow funnel/cylinder autonomously restricting flow port area available for inflow. Design and optimization methodology are presented with preliminary results of system mechanical and flow performance analysis. Further, the synthesis and characterization of the selective dissolvable layers is discussed.

Multi-mode vibration control using single actuator and single sensor is considered as a difficult control scheme. Most researchers use multi actuators and multi controllers to control multimode structural vibrations. In the present work, a multi-mode control model consists of a single actuator and single sensor, both attached at the top of simply supported thin plate, is developed. A piezoelectric actuator is used and it is assumed to be perfectly bonded to the plate, which means the bonding thickness is neglected. The sensed accelerometer signal is integrated and then filtered to include only the first and the second vibration modes. The linear equations of motion of the plate are derived and discretized using Galerkin’s Method. The resulting coupled equations are combined with velocity delay feedback controller to reduce the structure vibration. Genetic Algorithm is then used to optimize controller parameters using the root mean square of the input signal as an objective function. The results showed that the use of single-input single-output (SISO) delay feedback multimode controller can efficiently be used on any structure to control multimode systems.

Abstract In cold spraying, the required heat for bonding is provided by plastic deformation of the impacting ductile particles. Therefore, cold spraying is a well-established method for metal on metal coatings. However, few authors have investigated the impact phenomena and layer formation process for impacting brittle ceramic particles on ductile metal surfaces. For this study, titanium dioxide (TiO2) on metal surfaces was chosen as a model system, and layer formation on aluminum, copper, titanium and steel substrates was investigated by SEM, TEM, XRD and Raman spectroscopy. The results show that the deposition efficiency depends on spray temperature, powder properties, and in particular on substrate ductility, even for an impact of ceramic particles during a second pass over already coated areas. High-resolution TEM images revealed no crystal growth or phase transitions at the ceramic/metal interfaces. Nevertheless, a clear dependence of the photocatalytic activity on spray parameters and substrate material could be observed. Cold-sprayed TiO2-coatings have potential applications in biomedical implants or as photo-catalytic functional systems

As our society becomes increasingly information-oriented, various high-tech devices are developed to support its growth. As these high-tech devices become more and more advanced and compact in the recent years, the optical and electronic part, which make up these devices also need to be more accurate and smaller. These parts are commonly ground by loose abrasive lapping and polishing, but these methods have such disadvantages as wastewater processing problem, mechanical damages, wear by scatting abrasives, dirty workplace, and difficulty in using different grains on the same machine. For these reasons, new grinding methods are required as alternatives to the finishing method using loose abrasives. To answer to such needs, the authors have proposed a lap grinding method applying the electrically in-process dressing1) (ELID-lap grinding2)) and are carrying out studies to realize efficient and highly accurate machining. The latest bonding system which is composed of metal and resin was investigated for the ELID-lap grinding in order to improve the grinding quality by addition of the vibration absorbing function during grinding operation3). In this paper, Si which is typical material for X-ray mirror, was ground using metal-resin bonded wheels with different grain sizes, and the grinding characteristics were investigated.

Abstract Spacers are a very important element to have good cement bonding and to ensure well integrity. Spacers are used to prevent the contamination of the cement slurry by removing such materials and pushing them ahead toward the surface to separate the drilling fluid from the cement slurry. During the cement displacement process, and once the clay formation is in contact with the water present in the cement slurry, shales will be swelled or cracked due to the hydration reaction or water adsorption. Therefore, it is very helpful to make a spacer with efficient properties that help in protecting the clay formation from the water and prevent or minimize the hydration process by adding shale inhibiter to the spacer mixture formula. In this study, we will investigate the impact of KCL and a novel amine-based shale inhibitor on clay formation and investigate how these chemicals work to enhance spacer functions. The spacer has to be compatible with the drilling fluid and the cement slurry at the same time. Our study includes the compatibility test, rheology, thickening time test, as well as dispersion test for both KCl and novel amine based shale inhibitors.

In many advanced combustor concepts, such as the RQL (rich-quench-lean) combustor, the requirement of low NOx emission makes film cooling of the hot gas path surfaces undesirable. Double-walled structures with relatively low aspect ratio (height/width) rectangular passages and with well-controlled thin hot gas side metal walls are an alternative to film cooling. The additional application of other cooling techniques, such as impingement and surface enhancements, make efficient use of the limited cooling air available. However, the use of cooling channels to increase heat transfer coefficients on the coolant side may ultimately require well-bonded structures. Alternate methods of bonding have been considered for Ni-base alloy HA230-to-HA230 joints in thin-walled structures, with emphasis on bonds produced by hot isostatic pressing and by laser welding. For hot isostatic pressed (HIPed) structures, mechanical strength and ductility have been measured as a function of temperature for structures prepared after a number of different surface cleaning treatments prior to joining. The surface cleanliness has been characterized by scanning electron microscopy, and the after-HIP bond line microstructure has been evaluated as formed and after mechanical testing. Characterization of laser welds produced at Laserdyne for Acraline Products has consisted of scanning electron microscopy of the weld surfaces and metallography of weld/substrate cross-sections, looking at solidification/heat affected features and defects.

Nanowires based GMR is ideal to be integrated in microfluidic devices due to its efficient detection of sensitive magnetic fields. Nanowire based GMR microfluidic sensor is used to detect different fluids based on their magnetic behavior. This paper demonstrates the fabrication and testing of nanowire based GMR biosensors with four different control solutions: 1) DI-water, 2) Phosphate Buffered Saline (PBS), 3) polystyrene superparamagnetic beads, and 4) commercially available magnetic Dynabeads. The device is fabricated in PDMS by using a lithographically patterned silicon wafer as the mold. The nanowire based GMR material, 3 mm by 3 mm in size, is inserted inside the PDMS close to the channel during the fabrication. The channel in the PDMS substrate is sealed by bonding it to a glass plate using Reactive-Ion-Exchanger (RIE). GMR device is tested potentiostatically using a computer controlled function generator (Solatron, SI 1287). A highest resistance of 0.748 Ω. is recorded for the sensor, in the absence of magnetic field. A resistance change of 0.6% is obtained in the presence of a magnetic field (B = 0.035T) between water and polystyrene superparamagnetic beads when pumped through the microchannel. The sensor showed a resistance difference of 0.31% between 1X diluted PBS and 100X diluted dynabeads, in the presence of a constant magnetic field of 0.035T. This characterization would be useful in the development of a BioMEMS sensor using nanowire based GMR.

Abstract Recently the availability of various materials and ongoing research in developing advanced systems for multi-material additive manufacturing (MMAM) have opened doors for innovation in functional products. One major concern of MMAM is the strength at the interface between materials. This paper hypothesizes overlapping and interlacing materials to enhance the bonding strength. To test this hypothesis, we need a computer-aided manufacturing (CAM) tool that can process the overlapped material regions. However, existing computational tools lack key multi-material design processing features and have certain limitations in making full use of the material information, which restricts the testing of our hypothesis. Therefore, this research also develops a new MMAM slicing framework that efficiently identifies the boundaries for materials to develop different advanced features. By modifying a ray tracing technology, we develop layered depth material images (LDMI) to process the material information from computer-aided design (CAD) models for slicing and process planning. Each sample point in the LDMI has associated material and geometric properties that are used to identify the multi-material regions. Based on the material information in each slice, interlocking joint (T-Joint) and interlacing infill are generated in the regions with multiple materials. Tensile tests have been performed to verify the enhancement of mechanical properties by the use of overlapping and interlacing materials.

In this paper an isotropic hardening elastoplastic constitutive model for structured soils is applied to the simulation of a standard CPTu test in a saturated soft structured clay. To allow for the extreme deformations experienced by the soil during the penetration process, the model is formulated in a fully geometric non-linear setting, based on: i) the multiplicative decomposition of the deformation gradient into an elastic and a plastic part; and, ii) on the existence of a free energy function to define the elastic behaviour of the soil. The model is equipped with two bonding-related internal variables which provide a macroscopic description of the effects of clay structure. Suitable hardening laws are employed to describe the structure degradation associated to plastic deformations. The strain-softening associated to bond degradation usually leads to strain localization and consequent formation of shear bands, whose thickness is dependent on the characteristics of the microstructure (e.g, the average grain size). Standard local constitutive models are incapable of correctly capturing this phenomenon due to the lack of an internal length scale. To overcome this limitation, the model is framed using a non-local approach by adopting volume averaged values for the internal state variables. The size of the neighbourhood over which the averaging is performed (characteristic length) is a material constant related to the microstructure which controls the shear band thickness. This extension of the model has proven effective in regularizing the pathological mesh dependence of classical finite element solutions in the post-localization regime. The results of numerical simulations, conducted for different soil permeabilities and bond strengths, show that the model captures the development of plastic deformations induced by the advancement of the cone tip; the destructuration of the clay associated with such plastic deformations; the space and time evolution of pore water pressure as the cone tip advances. The possibility of modelling the CPTu tests in a rational and computationally efficient way opens a promising new perspective for their interpretation in geotechnical site investigations.