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Novel Composite (novel + composite)
Selected AbstractsIn Situ Growth of Mesoporous SnO2 on Multiwalled Carbon Nanotubes: A Novel Composite with Porous-Tube Structure as Anode for Lithium Batteries,ADVANCED FUNCTIONAL MATERIALS, Issue 15 2007Z. Wen Abstract A novel mesoporous-nanotube hybrid composite, namely mesoporous tin dioxide (SnO2) overlaying on the surface of multiwalled carbon nanotubes (MWCNTs), was prepared by a simple method that included in situ growth of mesoporous SnO2 on the surface of MWCNTs through hydrothermal method utilizing Cetyltrimethylammonium bromide (CTAB) as structure-directing agents. Nitrogen adsorption,desorption, X-ray diffraction and transmission electron microscopy analysis techniques were used to characterize the samples. It was observed that a thin layer tetragonal SnO2 with a disordered porous was embedded on the surface of MWCNTs, which resulted in the formation of a novel mesoporous-nanotube hybrid composite. On the base of TEM analysis of products from controlled experiment, a possible mechanism was proposed to explain the formation of the mesoporous-nanotube structure. The electrochemical properties of the samples as anode materials for lithium batteries were studied by cyclic voltammograms and Galvanostatic method. Results showed that the mesoporous-tube hybrid composites displayed higher capacity and better cycle performance in comparison with the mesoporous tin dioxide. It was concluded that such a large improvement of electrochemical performance within the hybrid composites may in general be related to mesoporous-tube structure that possess properties such as one-dimensional hollow structure, high-strength with flexibility, excellent electric conductivity and large surface area. [source] Microstructure and Compression Strength of Novel TRIP-Steel/Mg-PSZ Composites,ADVANCED ENGINEERING MATERIALS, Issue 12 2009Horst Biermann Abstract Novel composites on basis of austenitic stainless TRIP-steel as matrix with reinforcements of Mg-PSZ are presented. Compact rods were produced by cold isostatic pressing and sintering, square honeycomb samples by the ceramic extrusion technique. The samples are characterized by optical and scanning electron microscopy before and after deformation, showing the microstructure and the deformation- induced martensite formation. The mechanical properties of samples with 5,vol% zirconia are superior compared to zirconia-free samples and composites with higher zirconia contents in terms of bending and compression tests. The honeycomb samples exhibit extraordinary high specific energy absorption in compression. [source] In vitro change in mechanical strength of ,-tricalcium phosphate/copolymerized poly- L -lactide composites and their application for guided bone regenerationJOURNAL OF BIOMEDICAL MATERIALS RESEARCH, Issue 2 2002Masanori Kikuchi Abstract Novel composites of bioactive ,-tricalcium phosphate [Ca3(PO4)2] and biodegradable copolymerized poly- L -lactide (CPLA) were prepared by a heat-kneading method. The mechanical and chemical changes of the composites were evaluated in vitro by soaking in physiological saline and Dulbecco's phosphate buffered saline. When soaked in physiological saline, the 3-point mechanical strength decreased rapidly from 60 to 30 MPa in the initial 4 weeks and then gradually reached a plateau; the initial decrease in the mechanical strength was ascribed to the dissolution of ,-tricalcium phosphate from the surface. The mechanical properties evident at 8,12 weeks were sufficient for the composites to be used as a biodegradable material for regeneration of bone because the hydrolysis of CPLA was inhibited in both physiological saline and phosphate-buffered saline as a result of a pH-buffering effect. Composite membranes 250-,m thick were used to regenerate large bone defects in beagle dogs: 10 × 10 × 10 mm3 in volume in the mandible and 20 mm in length in the tibia. The afflicted areas covered with the composite membranes were almost perfectly filled with new bone 12 weeks after the operation, whereas those covered with a CPLA membrane or without any membranes were invaded by soft tissue. © 2002 Wiley Periodicals, Inc. J Biomed Mater Res 62: 265,272, 2002 [source] Synthesis and Low Cycle Fatigue Behavior of In-situ Al-based Composite Reinforced with Submicron TiB2 and TiC Particulates,ADVANCED ENGINEERING MATERIALS, Issue 12 2004S.C. Tjong Low cycle fatigue behavior of in-situ aluminum based composite reinforced with submicron TiB2 and TiC particulates was investigated. This novel composite was prepared from the TiO2 -Al-B-C system via reactive hot pressing. The incorporation of carbon into such a system induces the formation of TiC particulate at the expense of brittle Al3Ti phase. The influence of submicron particulate formation on the tensile and fatigue properties of the composite is discussed. [source] Magnetic Multi-Functional Nano Composites for Environmental ApplicationsADVANCED FUNCTIONAL MATERIALS, Issue 8 2009Jie Dong Abstract A novel concept is proposed to synthesize a new class of composites featuring magnetic, molecular sieve and metallic nanoparticle properties. These multi-functional materials have potential applications as recyclable catalysts, disinfectants and sorbents. The magnetic property enables effective separation of the spent composites from complex multiphase systems for regeneration and recycle, safe disposal of the waste and/or recovery of loaded valuable species. The zeolite molecular sieve provides a matrix which supports a remarkably new, simple, efficient and economical method to make stable, supported silver nanoparticles by silver ion exchange and controlled thermal reduction. The silver nanoparticles generated in this way have excellent properties such as high reactivity and good thermal stability without aggregation, which act as nano reactors for desired functionality in a wide range of applications. Magnetic component (Fe3O4), molecular sieve matrix (zeolite) and silver nanoparticles generated by ion exchange followed by controlled reduction, together form this unique novel composite with designed functions. It represents a practically operational, economical, sustainable and environmentally friendly new advanced functional material. This paper focuses on the novel synthesis and characterization of the composite, with an example of applications as sorbents for the removal of vapor-phase mercury from the flue gas of coal-fired power plants. [source] "Tongue sandwich" bolster for skin graft immobilization,HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 7 2002Charles E. Butler MD Abstract Background Because of surface irregularities and continuous movement of the tongue, predictable immobilization of split-thickness skin grafts (STSGs) for tongue defects is difficult to achieve. Methods A novel composite, bilayer foam bolster was used to immobilize a STSG after reconstruction of more than 80% of the tongue mucosa after resection of a squamous cell carcinoma and extensive leukoplakia. Dorsal and ventral bolster components were placed over the STSG and affixed using transglossal, through-and-through sutures. Results The composite foam bolster provided uniform compression along the highly irregular and mobile skin-grafted surface. Graft survival was excellent, and there were no complications. Conclusions The "tongue sandwich" bolster is quickly and easily fabricated, immobilizes the tongue in a fully expanded position, and provides excellent apposition of STSGs to highly irregular and vascular surfaces. © 2002 Wiley Periodicals, Inc. Head Neck 24: 705,709, 2002 [source] Multilayer tendon slices seeded with bone marrow stromal cells: A novel composite for tendon engineeringJOURNAL OF ORTHOPAEDIC RESEARCH, Issue 7 2009Hiromichi Omae Abstract The ideal scaffold for tendon engineering would possess the basic structure of the tendon, native extracellular matrix, and capability of cell seeding. The purpose of this study was to assess the tissue engineering potential of a novel composite consisting of a decellularized multilayer sliced tendon (MST) scaffold seeded with bone marrow stromal cells (BMSC). BMSC and infraspinatus tendons were harvested from 20 dogs. The tendons were sectioned in longitudinal slices with a thickness of 50 µm. The slices were decellularized, seeded with BMSC, and then bundled into one composite. The composite was incubated in culture media for 14 days. The resulting BMSC-seeded MST was evaluated by qRT-PCR and histology. The BMSC viability was assessed by a fluorescent tracking marker. Histology showed that the seeded cells aligned between the collagen fibers of the tendon slices. Analysis by qRT-PCR showed higher tenomodulin and MMP13 expression and lower collagen type I expression in the composite than in the BMSC before seeding. BMSC labeled with fluorescent tracking marker were observed in the composite after culture. Mechanical testing showed no differences between scaffolds with or without BMSC. BMSC can survive in a MST scaffold. The increased tenomodulin expression suggests that BMSC might express a tendon phenotype in this environment. This new composite might be useful as a model of tendon tissue engineering. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27: 937,942, 2009 [source] | ||||||||||