Top PDF Design of new multifunctional materials

Design of new multifunctional materials

Design of new multifunctional materials

I have used principles of synthetic organic chemistry to guide the molecular design of materials that contain a variety of functionalities. This thesis describes three types of designed functional materials. First, new heterogeneous catalysts have been prepared that incorporate two organic functional groups in a manner that allows for cooperativity between them in catalyzing organic reactions, giving increases in reaction rates and selectivities. In particular, thiol/sulfonic acid bi-functional mesoporous materials have been prepared that give significant enhancements in reactivity and selectivity towards bisphenol A synthesis. These enhancements arise from interactions between thiol and sulfonic acid sites due to their proximity on the surface of the catalyst. Acid-base bi-functional materials have also been synthesized that exhibit excellent reactivity in the aldol condensation between acetone and 4-nitrobenzaldehyde. These catalysts are particularly important as the acid and base groups are mutually incompatible in solution and provide reactivity not achievable without immobilization on the surface of solids. Second, a method for incorporating traceable and quantifiable labels onto
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Multiscale Design of Materials

Multiscale Design of Materials

Current methods of materials development, relying mostly on experimental tests, are slow and expensive, often taking over a decade and costing many millions of dollars to develop and certify new materials for critical applications. Finding new approaches for materials development is essential. Moreover, it will be increasingly important for materials development to be integrated into overall product design and development. We discuss a program in which we are creating a framework to link multiscale materials information to do design across scales, based on an existing computational design platform, VE-Suite. We present the basic framework of our program and discuss progress to date. Since our goal is multiscale design, part of our efforts are focussed on creating new visualization tools and facilities to enhance the design process. We review progress in this area as well.
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Design and Synthesis of New Hydrogen Storage Materials Functioning by Weak Chemisorption

Design and Synthesis of New Hydrogen Storage Materials Functioning by Weak Chemisorption

interaction. 18-21 Kubas binding has been demonstrated in a series of metal-organic frameworks (MOF) and Prussian Blue materials, but none of these materials show enthalpies in the calculated 20-30 kJ/mol range. 22 Recently, a MOF possessing a binding enthalpy of 13.5 kJ/mol was synthesized. 23 The Ti fragments in our silica material retained a promising 41 % of their activity at room temperature, demonstrating that the higher enthalpies indeed lead to better performance at ambient temperature than pure physisorption, which generally shows less than 10 % of it activity under these conditions. One drawback of our system is that, although it shows reversibility over 20 cycles in laboratory conditions, the Ti fragments are thermally unstable and decompose over several weeks under nitrogen leading to lower performance. In this paper we study silica supported bis(benzene) and bis(cyclopentadienyl) vanadium and chromium analogues and show that the bis(cyclopentadienyl)chromium system possesses adsorption enthalpies up to 18.43 kJ/mol, the second highest recorded for a cryogenic material, and also possesses higher thermal stabilities than the Ti (III) system, retaining 100 % performance after three months storage under nitrogen. While these materials still possess adsorption capacities much lower than stipulated by the DOE, the aim of our studies is to establish trends in hydrogen binding at ambient temperatures and high pressures to extremely reactive metal centers grafted on silica surfaces which would otherwise be unstable and difficult to synthesize and study, with the long term goal of developing extended solids using the same underlying principles to meet and surpass these DOE goals.
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Multimodal design for hybrid course materials: developing a new paradigm for delivery

Multimodal design for hybrid course materials: developing a new paradigm for delivery

USQ has chosen to deliver material on CD as against solely online for a number of reasons. Primarily it is due to the ‘tyranny of broadband’ (Bruch, 2003), or the variability and inconsistency of Internet connection both within Australia and in the many countries to which course materials are supplied. This inconsistency has made the delivery of high quality web based resources problematic. The National Office for the Information Economy in Australia recently released the ‘Australian National Broadband Strategy’ on behalf of the Federal Government. This report indicated that due to population densities in most rural and remote areas in Australia it is unlikely that equitable access to broadband technology will be achieved in the near future (NOIE, 2004, p.4).
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Multiscale Design of Materials

Multiscale Design of Materials

Current methods of materials development, relying mostly on experimental tests, are slow and expensive. It often takes over a decade and costs many millions of dollars to develop and certify new materials for critical applications. With evolving constraints being placed on the use of materials arising from concerns with energy and materials resource sustainability, new approaches for materials development is essential. Moreover, it is increasingly important for materials development to be integrated into overall product design and development, allowing for optimal use of materials as well as enhancing our ability to recycle and reuse. In this paper, we discuss a new program in which we link methodologies developed over the past few decades in computational materials science to a modern computational design platform (VE-Suite) to enable the multiscale design of materials. Development of such multiscale design platforms is essential for the successful implementation of integrated computational materials engineering (ICME), an emerging discipline within materials development. We will present the basic framework of our program and discuss progress to date.
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Design and Fabrication of a Multifunctional Nano-on-micro Delivery System

Design and Fabrication of a Multifunctional Nano-on-micro Delivery System

The fate of many DEBs following therapy is currently unknown. When the loaded chemotherapeutic has been delivered, and treatment is not finished or the tumour recurs, further DEB-TACE is often needed. According to Lewis and Dreher, “the current materials are considered non-biodegradable which led to early objections to DEB therapy since it may not be possible to re-enter the feeding artery once this artery had been occluded” [15]. Multiple treatments are often needed [31] and a review of studies of HCC transarterial therapy found that the average number of sessions per patient was 2.5 ± 1.5 occurring 2 months apart [9]. It has been thought that non- biodegradable microparticles for TACE therapy should be used for single therapies and biodegradable versions should be used when repeated therapy is needed so ensure that the artery is not blocked [35]. In spite of this, non-biodegradable DEBs have been used clinically and multiple repeat DEB-TACE procedures in the same patient has been shown possible [50]. This does not, however, mean that there are no issues with the accumulation of DEBs at the tumour site without the ability to degrade, but that there is currently no option that properly addresses this. “There is an undercurrent of opinion that DEB evolution will eventually move in this biodegradable direction as an essential feature” [15].
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Design of Polymorphic Operators for Efficient Synthesis of Multifunctional Circuits

Design of Polymorphic Operators for Efficient Synthesis of Multifunctional Circuits

Systematic effort dedicated to the exploration of feasible ways how to permanently come up with even more space-efficient implementation of digital circuits based on conventional CMOS technology node may soon reach the ultimate point, which is mostly given by the constraints associated with physical scaling of fundamental electronic components. One of the possible ways of how to mitigate this problem can be recognized in deployment of multifunctional circuit elements. In addition, the polymorphic electronics paradigm, with its considerable independence on a parti- cular technology, opens a way how to fulfil this objective through the adoption of emerging semiconductor materials and advanced synthesis methods. In this paper, main attention is focused on the introduction of polymorphic operators (i.e. digital logic gates) that would allow to further increase the efficiency of multifunctional circuit synthesis techniques. Key aspect depicting the novelty of the proposed approach is primarily based on the intrinsic exploitation of components with ambi- polar conduction property. Finally, relevant models of the polymorphic operators are presented in conjunction with the experimental results.
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A New Materials and Design Approach for Roads, Bridges, Pavement, and Concrete

A New Materials and Design Approach for Roads, Bridges, Pavement, and Concrete

The results show that at low wind velocities (<0.1 m/s) and under steady state conditions, asphalt surface temperature is always higher than PCC surface temperature. However, at wind velocities higher than 0.1 m/s, the steady state surface temperatures of the two materials are almost the same. Significantly, this result disproves that PCC is universally a cooler material than asphalt. Previous researchers typically used 0.1 as the albedo for black asphalt pavements and 0.8 as the albedo for white PCC pavements. The model uses these values as inputs. Based on observations by previous researchers, the CFD model accurately predicts asphalt pavement surface temperatures being higher than PCC surface temperatures. However, it also suggests that at higher wind velocities, asphalt and PCC pavements may contribute equally towards UHI.
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Design and microfabrication of multifunctional bio-inspired surfaces

Design and microfabrication of multifunctional bio-inspired surfaces

The potential widespread interest of superhydrophobicity on industrial applications has driven the application research effort in this area. Current effort targets to improve reliability and manufacturability for a cost-effective industrialization of such materials. A car windshield that can be cleaned and allows to see perfectly during heavy rain, a pair of gloves that can be immersed in mud and come out clean as new, or even a boat hull that does not need to be cleaned from biofouling and molluscs, are examples of near-to-market products based on super- hydrophobic materials. The research effort that can bring the fabrication technology to a mature phase needs to address the fundamental characteristics that define a surface to be super- hydrophobic: contact angle (static and hysteresis), and the stability of intrinsically hydrophobic and hydrophilic substrates. 1.2.1 Contact angle and contact angle hysteresis
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Multifunctional Upconversion-Magnetic Hybrid Nanostructured Materials: Synthesis and Bioapplications

Multifunctional Upconversion-Magnetic Hybrid Nanostructured Materials: Synthesis and Bioapplications

The combination of nanotechnology and biology has developed into an emerging research area: nano-biotechnology. Upconversion nanoparticles (UCNPs) have attracted a great deal of attention in bioapplications due to their high chemical stability, low toxicity, and high signal-to-noise ratio. Magnetic nanoparticles (MNPs) are also well-established nanomaterials that offer controlled size, ability to be manipulated externally, and enhancement of contrast in magnetic resonance imaging (MRI). As a result, these nanoparticles could have many applications in biology and medicine, in- cluding protein purification, drug delivery, and medical imaging. Because of the potential benefits of multimodal functionality in biomedical applications, researchers would like to design and fabricate multifunctional upconversion-magnetic hybrid nanostructured materials. The hybrid nanostruc- tures, which combine UCNPs with MNPs, exhibit upconversion fluorescence alongside super- paramagnetism property. Such structures could provide a platform for enhanced bioimaging and controlled drug delivery. We expect that the combination of unique structural characteristics and integrated functions of multifunctional upconversion-magnetic nanoparticles will attract increasing research interest and could lead to new opportunities in nano-bioapplications.
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Design as conversation with digital materials

Design as conversation with digital materials

relationships between configurations of symbols in the notation, and expected responses. Introducing a new tool for designing is an intervention in an established system of artefacts, practices and interpretations. Spinuzzi & Zachry (2000) characterise such systems in terms of ‘genre ecologies’. As Coyne et al. (2002) observe, new digital devices introduce “new practices, new terms and metaphors …new work patterns and practices … new forms of organisation, new specialisms …” (ibid., p271). Successful adoption of a new tool then depends on finding a successful niche in relation to the established genre ecology. As with any ecology, if a new device finds such a niche, it may displace or transform related devices and activities as the genre ecology evolves. Blandford et al. (2002) have proposed a way of exploring tensions between the
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Physical, thermal, and dielectric properties enhancement in graphene/poly 
		(Vinyl Alcohol) nanocomposite as novel multifunctional materials

Physical, thermal, and dielectric properties enhancement in graphene/poly (Vinyl Alcohol) nanocomposite as novel multifunctional materials

In recent years, multifunctional nanocomposites are increasingly needed for applications requiring prescribed sets of physical, thermal and electrical properties. Polymeric nanocomposites offer design engineers a wide range of tuneable materials properties that would enhance the polymer properties and extend their applications to new areas. The development of materials like graphene has revitalized nanocomposite science and technology which led to the evolution of a new generation of materials. Nanocomposite is one of the most promising approaches to enhance the polymer properties by combining the light weight and flexibility of polymers with the extraordinary mechanical and thermal properties of the nanofiller at far lower reinforcement concentrations than their conventional micro and macro counterpart. However, maximal mechanical enhancement can only be achieved when the nanofiller is dispersed homogeneously, or best at the molecular level, in the matrix and the external load is efficiently transferred via a strong interaction at the interface between the filler and the matrix [1].
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Getters: From Classification to  Materials Design

Getters: From Classification to Materials Design

The demand for getters with high sorption efficiency has generated a need for resources to assist in qualification of getter materials for their practical use. This paper discusses innovative steps which should provide a dramatic improvement in the selection and application of getter technolo- gies used in various processes. The first step was to build a natural classification of chemisorbents, from which we obtain a corresponding order of suitability related to known getter products. The classification system suggested by the authors is based on criteria which are directly connected with the sorption behavior of the material. This has lead to the challenge of developing of a com- puting algorithm for characterization of sorption properties of getter materials and for solving the inverse problem—the problem of designing a chemisorbent based on the requirements of a fully realized application. The employment of the new methodology is demonstrated in the example of the calculations supporting the selection of getter films for MEMS.
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Instructional Materials and Design: Issues and Challenges

Instructional Materials and Design: Issues and Challenges

It was the opinions of male and female teachers in public secondary schools in Udi Education zone of Enugu State that to a great extent, the instructional materials available for use in school are of inferior design, out-dated, not durable and have high maintenance cost. The respondents also shared the same opinion that they are of low quality, do not appeal to students intellectual development, do not match the new teaching methods of the teachers and were poorly designed. The findings agree with the news of Mkpa (2003) that in most schools, the available instructional materials are of poor quality in design. The findings are also supportive of Babalola (2004) that most of the available instructional materials in use in schools are lacking in stimulating the students intellectual growth.
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Design of Particulate-Reinforced Composite Materials

Design of Particulate-Reinforced Composite Materials

dielectrics have been estimated numerically by Wu et al. [20]. Krakovsky and Myroshnychenko [21] used the finite element method to compute the effective permittivity for two-dimensional random composites. Numerical approach to the evaluation of the effective properties for MR fluids is demonstrated in Ref [22], however the analysis and results deal only with the prediction of magnetic permeability in one direction only. Although materials with directional features are common, most previous work has focused on the isotropic cases, except some studies attempted to bring this property-direction dependence into general formulation. For instance for MR fluids some magnetic properties, such as the saturation magnetization and the crystalline anisotropy, are intrinsic and depend mainly on the chemical composition and the crystalline symmetry of the material. On the other hand, extrinsic properties, such as remanence, coercivity and permeability, depend largely on the structure of the material Yin and Sun [16] or on the shape of reinforced particles [23]. Through analytical predictions and numerical modeling, certain optimization approaches and design schemes for novel materials could be resulted for engineering applications, and in turn the new observations and experiences from the practice would accelerate the development of new theories and methodologies.
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Design of New Evaporative Cooler and Usage of Different Cooling Pad Materials for Improved Cooling Efficiency

Design of New Evaporative Cooler and Usage of Different Cooling Pad Materials for Improved Cooling Efficiency

A new evaporative cooling system is designed and compared with rectangular shaped cooler with respect to temperature drop, humidity rise and cooling efficiency. Performance of four pad materials i.e Khus, Celdek, coconut and bamboo fiber is evaluated by using normal water and chilled water. The performance criterion includes temperature drop, humidity variations and cooling efficiency. The results obtained are as follows:

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Guiding the design and application of new materials for enhancing sustainability performance: Framework and infrastructure application

Guiding the design and application of new materials for enhancing sustainability performance: Framework and infrastructure application

agency and social costs can be evaluated. The application of this integrated model to bridge deck joint design highlighted the critical importance of using the life cycle modeling in order to enhance the sustainability of infrastructure systems. This study showed that the ECC link slab bridge deck design resulted in significantly lower environmental impacts and costs over a 60 year bridge deck service life compared to the conventional steel expansion joint system. A key finding from life cycle modeling was the dominance of construction related traffic on the environmental performance of both deck systems. Consequently, predicting maintenance and repair schedules for each system is critical in evaluating the performance of alternative materials. The repair and rehabilitation timeline drives the results for both the LCA and LCC. This underscores the need for a reliable model for service schedule prediction, and the design and material choices that affect the schedule.
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Multimodal design and hybrid course materials: developing a new paradigm for course delivery at USQ

Multimodal design and hybrid course materials: developing a new paradigm for course delivery at USQ

An important aspect in catering for a variety of learning styles, particularly relevant in today’s highly visual culture, is the use of images. Stokes (2002) asserts that using visual strategies in teaching results in a greater degrees of learning. Felder and Soloman (2001) agree, further suggesting that if sufficient visual content were included in learning materials students would retain more information. Although visual images are an integral part of human cognition, they have tended to be marginalised and undervalued in today’s higher education systems (McLoughlin & Krakowski, 2001). Unfortunately, in traditional DE courses this problem seems to be exacerbated with students interacting with study books or computer screens containing very few visual references (Sankey, 2001).
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The design and synthesis of new molecule based magnetic materials

The design and synthesis of new molecule based magnetic materials

Among the enormous number of magnetic solids prepared, characterized and exploited in the last century, molecule-based magnetic materials have brought many new features. Although there may be a long way to go before we see molecule-based magnets in many applications, it is hopeful that the research is aiming for new applications and complementing rather than replacing of existing magnetic materials. Additionally, as a very new research area, there is huge scope for the synthesis of new molecular materials. In doing so, this undoubtedly will give new impetus to those relevant fields such as supramolecular and coordination chemistry, or even purely organic synthetic chemistry.
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Multifunctional Nanostructured Materials Applied in Controlled Radiopharmaceuticals Release

Multifunctional Nanostructured Materials Applied in Controlled Radiopharmaceuticals Release

The cytotoxicity profile of a new material should be in- vestigated since undesirable side effects can occurs when this material is used in in vivo applications. The cytotox- icity of the hybrid [SBA-15/P(N-iPAAm)] and SBA 15 were evaluated through MTT assay, and the results show- ed that the groups of cells exposed to SBA-15 and [SBA- 15/P(N-iPAAm)], in all tested concentrations, presented a viability of approximately 100% (Figure 6).

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