Ceramics surface modification

The so-called dry mixing or dry blending method has been used for the modification of" particles in the powder technology (59). In this method, surface modification of coarse particles is carried out by mixing fine particles and coarse particles with an auto ceramic mortar or with a centrifugal rotating mixer. This procedure can be applicable for the production of variety of composite magnetic particles. 

Polymer surfaces are modified to obtain the desired surface properties without altering the bulk properties (J ). One of the most desired properties is adhesion between polymers and other materials such as polymers, metals or ceramics (2). There are many techniques for polymer surface modification, but they can be divided into two major categories. One is a dry process in which the polymers are modified with vapor-phase reactive species that are... 

The aforementioned requirements on surface stability are typical for all exposed areas of the metallic interconnect, as well as other metallic components in a SOFC stack (e.g., some designs use metallic frames to support the ceramic cell). In addition, the protection layer for the interconnect, or in particular the active areas that interface with electrodes and are in the path of electric current, must be electrically conductive. This conductivity requirement differentiates the interconnect protection layer from many traditional surface modifications as well as nonactive areas of interconnects and other components in SOFC stacks, where only surface stability is emphasized. While the electrical conductivity is usually dominated by their electronic conductivity, conductive oxides for protection layer applications often demonstrate a nonnegligible oxygen ion conductivity as well, which leads to scale growth beneath the protection layer. With this in mind, a high electrical conductivity is always desirable for the protection layers, along with low chromium cation and oxygen anion diffusivity. 

J. Randon, H. de Lucena Lira and R. Paterson, Improved separations using surface modification of ceramic membranes, in Yi Hua Ma (Ed.), Proceedings of the Third International Conference on Inorganic Membranes, 10-14 July 1994, Worcester, USA. Worcester Polytechnic Institute, 100 Institute Road, Worcester, MA 01609, USA, pp. 429-435. 

Liden, E. et al.. Surface modification and dispersion of silicon nitride and silicon carbide powders, J. Eur. Ceram. Soc., 7, 361, 1991. 

Yao, S. and Stetter, J.R. (2005) Solid-state NOx sensor based on surface modifications of the solid electrolyte. Proceedings of the Electrochemical Society, 2000-52 Solid-State Ionic Devices II Ceramic Sensors, The Electrochemical Society, Pennington. New Jersey, pp. 252-60. 

In recent years simultaneous progress in the understanding and engineering of block copolymer microstructures and the development of new templating strategies that make use of sol-gel and controlled crystalHzation processes have led to a quick advancement in the controlled preparation of nanoparticles and mesoporous structures. It has become possible to prepare nanoparticles of various shapes (sphere, fiber, sheet) and composition (metal, semiconductor, ceramic) with narrow size distribution. In addition mesoporous materials with different pore shapes (sphere, cyHndrical, slit) and narrow pore size distributions can be obtained. Future developments will focus on applications of these structures in the fields of catalysis and separation techniques. For this purpose either the cast materials themselves are already functional (e.g., Ti02) or the materials are further functionalized by surface modification. 

Hendren ZD, Brant J, and Wiesner MR. Surface modification of nanostructured ceramic membranes for direct contact membrane distillation. J. Membr. Sci. 2009 331 1-10. 

A wide variety of natural and synthetic materials have been used for biomedical applications. These include polymers, ceramics, metals, carbons, natural tissues, and composite materials (1). Of these materials, polymers remain the most widely used biomaterials. Polymeric materials have several advantages which make them very attractive as biomaterials (2). They include their versatility, physical properties, ability to be fabricated into various shapes and structures, and ease in surface modification. The long-term use of polymeric biomaterials in blood is limited by surface-induced thrombosis and biomaterial-associated infections (3,4). Thrombus formation on biomaterial surface is initiated by plasma protein adsorption followed by adhesion and activation of platelets (5,6). Biomaterial-associated infections occur as a result of the adhesion of bacteria onto the surface (7). The biomaterial surface provides a site for bacterial attachment and proliferation. Adherent bacteria are covered by a biofilm which supports bacterial growth while protecting them from antibodies, phagocytes, and antibiotics (8). Infections of vascular grafts, for instance, are usually associated with Pseudomonas aeruginosa Escherichia coli. Staphylococcus aureus, and Staphyloccocus epidermidis (9). 

Li conducting pathways at the ceramic surface [44-46]. Therefore, according to this model, the structural modifications at microscopic levels promote consistent enhancement in the transport properties of the electrolyte. In addition, the all-solid configuration (no addition of liquids) gives to these nanocomposite electrolytes a high compatibility with the lithium metal electrode [47-50], all these properties making them suitable for use as safe and efficient separators in rechargeable lithium batteries [51]. 

Chu, L.Y., Wang, S. and Chen, W.M. 2005. Surface modification of ceramic-supported poly-ethersulfone membranes hy interfacial polymerization for reduced membrane fouling. 

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