Materials application potential

The appearance of the 2-(indol-3yl)ethylamine (tryptamine) unit in both tryptophan-derived natural products and in synthetic materials having potential pharmacological activity has generated a great deal of interest in the synthesis of such compounds. Several procedures which involve either direct 3-alkylation or tandem 3-functionalization/modification have been developed. Similarly, methodology applicable to preparation of tryptophan analogues has been widely explored. 

Wang and coworkers first reported the use of these monomers as a novel elastomeric material for potential application in soft tissue engineering in 2002. The molar ratio of glycerol to sebacic acid they used was 1 1. The equimolar amounts of the two monomers were synthesized by polycondensation at 120°C for three days. The reaction scheme is shown in Scheme 8.1. To obtain the elastomers, they first synthesized a prepolymer and then poured an anhydrous 1,3-dioxolane solution of the prepolymer into a mold for curing and shaping under a high vacuum. 

In conclusion, all these types of light-induced reactions involving polyphosphazenes readily account for the great importance assumed by this topic in the phosphazene domain and for the remarkable application potentials of especially designed phosphazene materials. 

The interaction of dihalogens, particularly diiodine, with sulfur and selenium electron donors has been an area of increasing interest over the past decade because of potential biological, pharmaceutical, and electronic materials applications [35,179]. Devillanova and coworkers have recently reviewed the solution behavior of a large number of chalcogenides and I2, particularly thiones, selones, sulfides, and selenides [180]. Correlations between computational methods, thermodynamic parameters, and spectroscopic data (UV/Vis, 13C NMR, Raman, UPS) were discussed. 

From an engineering perspective, recycled materials should be used in such a manner that the expected performance of the product will not be compromised. Waste and byproduct materials, however, differ vastly in their types and properties and, as a result, in the end-use applications for which they may be suited. Experience and knowledge regarding the use of these materials vary from material to material as well as from facility to facility. To recover these materials for potential use, engineers, researchers, generators, and regulators need to be aware of the properties of the materials, how they can be used, and what limitations may be associated with their use. 

Frache, A., Gianotti, E. and Marchese, L. (2003) Spectroscopic characterisation of micro-porous aluminophosphate materials with potential application in environmental catalysis, Catal. Today, 77, 371. 

The objectives of this research are to develop short-term in vitro fatigue test methodologies that will predict long-term in vivo performance of elastomers used in cardiac assistance and related devices and to evaluate the fatigue life of candidate materials for potential use in these applications. 

Besides the previously mentioned collagen, a wide variety of natural polymers have been involved in the synthesis of bio-nanohybrid materials with potential application in bone repair and dental prostheses. For instance, some recent examples refer to bionanocomposites based on the combination of HAP with alginate [96,97], chitosan [98,99], bovine serum albumin (BSA) [100], sodium caseinate [101], hyaluronic acid [102], silk fibroin [103,104], silk sericin [105], or polylactic add (PLA) [106,107]. These examples illustrate the increasing interest in the subject of HAP-based biohybrid materials, which has led to almost 400 articles appeared in scientific journals in 2006 alone. 

Research on alternative catalysts for the ORR for use in PEM fuel cell cathodes is an exciting and growing field of research. Several classes of materials show potential for replacing precious metal cathodes, especially for automotive power applications and direct methanol systems. Increasing the understanding of active sites in alternative catalysts, the mechanisms for oxygen reduction, and optimization of full fuel cell preparation using alternative materials, will lead to further improvements in performance. 

In order to achieve the firm fixation of the artificial cornea to host tissues, composites of collagen-immobilized poly(vinyl alcohol) hydrogel with hydroxyapatite were synthesized by a hydroxyapatite particles kneading method. The preparation method, characterization, and the results of corneal cell adhesion and proliferation on the composite material were studied. PVA-COL-HAp composites were successfully synthesized. A micro-porous structure of the PVA-COL-HAp could be introduced by hydrochloric acid treatment and the porosity could be controlled by the pH of the hydrochloric acid solution, the treatment time, and the crystallinity of the HAp particles. Chick embryonic keratocyto-like cells were well attached and proliferated on the PVA-COL-HAp composites. This material showed potential for keratoprosthesis application. Further study such as a long-term animal study is now required [241]. 

Nevertheless the euphoric optimism where these materials were allowed a huge potential in material applications has given way to a more realistic view. Nanocomposites are not a universal solution for reinforced materials. Their full potential can only be realised if every step in the added value chain is taken into account during the whole development process. From todays perspective nanocomposite materials with an improved thermal flammability resistance or improved barrier properties have the best chances to fulfil these requirements. 

The research plan is organized around a set of well-defined model systems and a limited number of detailed experiments. The experiments are designed to progress over a five-year period from fundamental studies on model systems to development of thin film materials with potential practical applications. Together they will form a coherent bond of film growth using LCI with a variety of molecular building and LC solvents. The expected outcomes of this work will be... 

Copper in minerals luminescence is usually considered only as an effective quencher. Nevertheless, it is well known that a bright blue luminescence is emitted from Cu ions in inorganic solids by UV light irradiation. It was found that these materials have potential application to tunable lasers. For example, in Ca0-P20s glasses Cu is characterized by a luminescence band at 440 nm with a half-width of 100 nm and an excitation maximum at 260 nm. The decay time of luminescence is approximately 25 ps (Tanaka et al. 1994). Red fluorescence possibly connected with the Cu" pair is also known (Moine et al. 1991). 

Mendes, S. C.,Bovell, Y. R.,Reis,R. L., Cunha, A. M., deBruijn, J. D., vanBlitterswijk, C. A. (2001). Biocompatibility testing of novel starch-based materials with potential application in orthopaedic surgery. Biomaterials., 22,2057-2064. 

McCarthy, G. J., Hassett, D. J. Bender, J. A. 1992. Synthesis, crystal chemistry and stability of ettringite, a material with potential applications in hazardous waste immobilization. Materials Research Society Symposium Proceedings, 245, 129-140. 

Carbon nanotubes are unique materials with specific properties [42]. There is a considerable application potential for using nanotubes in the biomedical field. However, when such materials are considered for application in biomedical implants, transport of medicines and vaccines or as biosensors, their biocompatibility needs to be established. Other carbon materials show remarkable long-term biocompatibility and biological action for use as medical devices. Preliminary data on biocompatibility of nanotubes and other novel nanostructured materials demonstrate that we have to pay attention to their possible adverse effects when then-biomedical applications are considered. 

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