Applications functional materials

The toughness of a material is a design driver in many structures subjected to impact loading. For those materials that must function under a wide range of temperatures, the temperature dependence of the various material properties is often of primary concern. Other structures are subjected to wear or corrosion, so the resistance of a material to those attacks is an important part of the material choice. Thermal and electrical conductivity can be design drivers for some applications, so materials with proper ranges of behavior for those factors must be chosen. Similarly, the acoustical and thermal insulation characteristics of materials often dictate the choice of materials. 

It is widely appreciated that the deterioration of metal and plastic implant materials within the body is one of the most important aspects of implant surgery. This particular application of materials places an almost unique demand on the resistance to deterioration. The reasons are basically twofold, for not only may the environmental effects alter the structure and properties of the material, which may itself affect the function of the implant and hence the well-being of the patient, but also the by-products of any structural change may have harmful effects on the patient... 

C.A. Schalley and F. Vogtle (eds), Dendrimers Functional and Hyperbranched Building Blocks, Photophysical Properties, Applications in Materials and Life Sciences, Vol 5, Springer-Verlag GmbH, Berlin and Heidelberg, 2003. 

Besides current development of new catalysts and related functional materials, oxidation tools have always played an important role in their synthesis, activation, and functionalization. After a separate discussion per technique we have rationalized our literature findings (Table 6.2) as five principal oxidative functions with many proven applications. 

The stndy and preparation of hollow capsules has attracted considerable attention in recent years. Hollow capsules are of immense interest in a long list of potential applications. These inclnde drug delivery, gene therapy, catalysis, waste removal, acoustic insulation, piezoelectric transducers, and functional materials [14],... 

In this brief review we illustrated on selected examples how combinatorial computational chemistry based on first principles quantum theory has made tremendous impact on the development of a variety of new materials including catalysts, semiconductors, ceramics, polymers, functional materials, etc. Since the advent of modem computing resources, first principles calculations were employed to clarify the properties of homogeneous catalysts, bulk solids and surfaces, molecular, cluster or periodic models of active sites. Via dynamic mutual interplay between theory and advanced applications both areas profit and develop towards industrial innovations. Thus combinatorial chemistry and modem technology are inevitably intercoimected in the new era opened by entering 21 century and new millennium. 

Dr Alexei Lapkin is a Senior Lecturer in Chemical Engineering at the University of Bath, UK, where he is also a Deputy Director of the Centre for Sustainable Chemical Technologies. He obtained his Master in Chemistry from the Novosibirsk State University, Russia, and Ph.D. in Chemical Engineering from the University of Bath. His research is focused on process intensification, bioprocessing, design and applications of functional materials. 

Thermal conductivity and heat capacity In practical applications, refractory materials processing high thermal capacity as well as low thermal conductivity are required, depending upon (of course) the functional requirements. In most situations, a refractory that serves as a furnace wall should have a low thermal conductivity in order to retain as much as heat as possible. However, a refractory used in the construction of the walls of muffles or retorts or coke ovens should have a high thermal conductivity in order to transmit as much heat as possible to the interior. The charge remains separated from flame in these specific examples of installations. 

In this review, the potential uses of sonochemistry for the preparation of monometallic and bimetallic metal nanoparticles and metal-loaded semiconductor nanoparticles have been highlighted. While specific examples available in the literature were discussed, the sonochemical technique seems to offer a platform technique that could be used for synthesizing a variety of functional materials. Most of the studies to date deal with laboratory scale exploration , it would be ideal if the concepts are tested under large scale experimental conditions involving specific applications. The authors sincerely hope that the information provided in this review would prompt such experimental investigation in a new dimension. 

Successful applications of materials in medicine have been experienced in the area of joint replacements, particularly artificial hips. As a joint replacement, an artificial hip must provide structural support as well as smooth functioning. Furthermore, the biomaterial used for such an orthopedic application must be inert, have long-term mechanical and biostability, exhibit biocompatibility with nearby tissue, and have comparable mechanical strength to the attached bone to minimize stress. Modem artificial hips are complex devices to ensure these features. 

The past two decades have produced a revival of interest in the synthesis of polyanhydrides for biomedical applications. These materials offer a unique combination of properties that includes hydrolytically labile backbone, hydrophobic bulk, and very flexible chemistry that can be combined with other functional groups to develop polymers with novel physical and chemical properties. This combination of properties leads to erosion kinetics that is primarily surface eroding and offers the potential to stabilize macromolecular drugs and extend release profiles from days to years. The microstructural characteristics and inhomogeneities of multi-component systems offer an additional dimension of drug release kinetics that can be exploited to tailor drug release profiles. 

Kempa, H. Fugmann, U. Hahn, U. Schmidt, G. Meier, B. Bartzsch, M. Fisher, T. Stanerl, M. Reuter, K. Preibler, K. Huebler, A. 2006. On the applicability of different mass printing methods for the deposition of organic functional materials. Proceedings of OEC-06 Peer Reviewed Papers, pp. 39. 

Two main fields of application have been explored fine chemistry/ pharmacy (Hessel et al. 2004a) and fuel processing (Hessel et al. 2005d). A few investigations target manufacture of bulk chemicals or intermediates. In addition, the production of smart and functional materials is the focus, such as pigments (Wille et al. 2004), encapsulated delivery... 

A large number of synthetic reactions via C-H bond activation have been reported in the last 10 years. In near future, applications to natural products and functional materials will be the next research targets, together with the development of new synthetic reactions. 

The ability to efficiently synthesize enantiomerically enriched materials is of key importance to the pharmaceutical, flavor and fragrance, animal health, agrochemicals, and functional materials industries [1]. An enantiomeric catalytic approach potentially offers a cost-effective and environmentally responsible solution, and the assessment of chiral technologies applied to date shows enantioselective hydrogenation to be one of the most industrially applicable [2]. This is not least due to the ability to systematically modify chiral ligands, within an appropriate catalyst system, to obtain the desired reactivity and selectivity. With respect to this, phosphorus(III)-based ligands have proven to be the most effective. 

As already mentioned, the most important industrial application of homogeneous hydrogenation catalysts is for the enantioselective synthesis of chiral compounds. Today, not only pharmaceuticals and vitamins [3], agrochemicals [4], flavors and fragrances [5] but also functional materials [6, 7] are increasingly produced as enantiomerically pure compounds. The reason for this development is the often superior performance of the pure enantiomers and/or that regulations demand the evaluation of both enantiomers of a biologically active compound before its approval. This trend has made the economical enantioselective synthesis of chiral performance chemicals a very important topic. 

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