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Ceramic Nanoparticles (ceramic + nanoparticle)
Selected AbstractsNovel Rice-shaped Bioactive Ceramic Nanoparticles (Adv. Eng.ADVANCED ENGINEERING MATERIALS, Issue 5 2009Mater. The cover of Advanced Biomaterials shows Rice-shaped bioactive ceramic nanoparticles with 70 nm in average diameter and around 200 nm in length were produced by an improved sol-gel method. In comparison to most traditional bioactive glass/ceramic materials this novel bioactive ceramic contains a significant lower quantity of silicon and higher content of phosphorous. In vitro bioactivity test showed that this new class of materials can induce the deposition of an apatite layer from SBF solution, having potential to be used in both conventional orthopedic applications or in bone tissue engineering when incorporated in composite scaffolds. More information can be found in the article of J. F. Mano et al. on page B25. [source] Novel Rice-shaped Bioactive Ceramic Nanoparticles,ADVANCED ENGINEERING MATERIALS, Issue 5 2009Zhongkui Hong Rice-shaped bioactive ceramic nanoparticles of 70 nm average diameter and around 200 nm length were produced by an improved sol-gel method. In comparison to most traditional bioactive glass/ceramic materials, this novel bioactive ceramic contains a significant lower quantity of silicon and higher content of phosphorous. In vitro bioactivity tests showed that this new class of materials can induce the deposition of an apatite layer from simulated body fluid, having the potential to be used in both conventional orthopedic applications or in bone tissue engineering when incorporated in composite scaffolds. [source] Novel Nanoparticle-Reinforced Metal Matrix Composites with Enhanced Mechanical PropertiesADVANCED ENGINEERING MATERIALS, Issue 8 2007C. Tjong Abstract This paper summarizes and reviews the state-of-the-art processing methods, structures and mechanical properties of the metal matrix composites reinforced with ceramic nanoparticles. The metal matrices of nanocomposites involved include aluminum and magnesium. The processing approaches for nanocomposites can be classified into ex-situ and in-situ synthesis routes. The ex-situ ceramic nanoparticles are prone to cluster during composite processing and the properties of materials are lower than the theoretical values. Despite the fact of clustering, ex-situ nanocomposites reinforced with very low loading levels of nanoparticles exhibit higher yield strength and creep resistance than their microcomposite counterparts filled with much higher particulate content. Better dispersion of ceramic nanoparticles in metal matrix can be achieved by using appropriate processing techniques. Consequently, improvements in both the mechanical strength and ductility can be obtained readily in aluminum or magnesium by adding ceramic nanoparticles. Similar beneficial enhancements in mechanical properties are observed for the nanocomposites reinforced with in-situ nanoparticles. [source] Stem Cell Aligned Growth Induced by CeO2 Nanoparticles in PLGA Scaffolds with Improved Bioactivity for Regenerative MedicineADVANCED FUNCTIONAL MATERIALS, Issue 10 2010Corrado Mandoli Abstract Hybrid 2D polymeric,ceramic biosupports are fabricated by mixing a nanostructured CeO2 powder with 85:15 poly(D,L -lactic- co -glycolic acid) (PLGA)/dichloromethane solutions at specific concentrations, followed by solvent casting onto pre-patterned molds. The mold patterning allows the orientation of ceramic nanoparticles into parallel lines within the composite scaffold. The ability of the produced films to host and address cell growth is evaluated after 1, 3, and 6 days of culturing with murine derived cardiac and mesenchymal stem cells (CSCs and MSCs), and compared with PLGA films without ceramics and loaded with nanostructured TiO2. Aligned cell growth is observed only for scaffolds that incorporate oriented ceramic nanoparticles, attributed to the nanoceramic ability to modulate the roughness pitch, thus improving cell sensitivity towards the host surface features. Better CSC and MSC proliferative activity is observed for CeO2 composites with respect to either TiO2 -added or unfilled PLGA films. This evidence may be related to the nanostructured CeO2 antioxidative properties. [source] Spontaneous Vertical Ordering and Pyrolytic Formation of Nanoscopic Ceramic Patterns from Poly(styrene- b -ferrocenylsilane),ADVANCED MATERIALS, Issue 4 2003K. Temple The rapid generation of nanopatterned surfaces using thin films of the amorphous diblock copolymer poly(styrene- b -ferrocenylethylmethylsilane) (PS- b -PFS) is reported. Spontaneous self-assembly into vertically oriented cylinders of PFS in a PS matrix is observed on a variety of substrates by spin or dip coating, irrespective of the substrate surface polarity. Pyrolysis of the films affords arrays of 20 nm Fe-containing ceramic nanoparticles, (see Figure, AFM, 4 ,m2 scan area). [source] Synthesis of silicon nitride based ceramic nanoparticles by the pyrolysis of silazane block copolymer micellesJOURNAL OF POLYMER SCIENCE (IN TWO SECTIONS), Issue 15 2006Kozo Matsumoto Abstract Diblock copolymer poly(1,1,3,N,N,-pentamethyl-3-vinylcyclodisilazane)- block- polystyrene (polyVSA- b -polySt) and triblock copolymer poly(1,1,3,N,N,-pentamethyl-3-vinylcyclodisilazane)- block- polystyrene- block -poly(1,1,3,N,N,-pentamethyl-3-vinylcyclodisilazane) (polyVSA- b -polySt- b -polyVSA), consisting of silazane and nonsilazane segments, were prepared by the living anionic polymerization of 1,1,3,N,N,-pentamethyl-3-vinylcyclodisilazane and styrene. PolyVSA- b -polySt formed micelles having a poly(1,1,3,N,N,-pentamethyl-3-vinylcyclodisilazane) (polyVSA) core in N,N -dimethylformamide, whereas polyVSA- b -polySt and polyVSA- b -polySt- b -polyVSA formed micelles having a polyVSA shell in n -heptane. The micelles with a polyVSA core were core-crosslinked by UV irradiation in the presence of diethoxyacetophenone as a photosensitizer, and the micelles with a polyVSA shell were shell-crosslinked by UV irradiation in the presence of diethoxyacetophenone and 1,6-hexanedithiol. These crosslinked micelles were pyrolyzed at 600 °C in N2 to give spherical ceramic particles. The pyrolysis process was examined by thermogravimetry and thermogravimetry/mass spectrometry. The morphologies of the particles were analyzed by atomic force microscopy and transmission electron microscopy. The chemical composition of the pyrolysis products was analyzed by X-ray fluorescence spectroscopy and Raman scattering spectroscopy. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 4696,4707, 2006 [source] Combustion synthesis of ceramic nanoparticles for solid oxide fuel cellsASIA-PACIFIC JOURNAL OF CHEMICAL ENGINEERING, Issue 4 2010Dehua Dong Abstract Two combustion synthesis methods involving the use of polyacrylamide hydrogel and humic acids (HAs) as fuels were developed to synthesize ceramic nanoparticles for fabrication of solid oxide fuel cells (SOFCs). Using polyacrylamide hydrogel as fuel, highly crystalline NiO/Ce0.8Sm0.2O1.9 (SDC) and SDC nanoparticles were synthesized to make a modified layer and subsequent dense electrolyte film on the anode support. HA was used as complexible fuel to synthesize Sm0.5Sr0.5CoO3 nanoparticles for preparing the SOFC porous cathode. The single SOFCs made from these nanoparticles exhibited a maximum power density of 740 mW cm,2 at 650 °C operated with H2/air as fuel/oxidant, suggesting the synthesized nanoparticles are of high quality as SOFC materials. 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