时间：9月27日（周五）10:00-12:00

地点：工艺楼403会议室

题目1：Carbon/Carbon composites – Control of Microstructure and Properties

报告人：L.M. Manocha
        Department of Materials Science, Sardar Patel University,
        Vallabh Vidyanagar – 388120, Gujarat, INDIA

摘要：Carbon/Carbon composites, though are now nearly four decade old materials and have been successfully used as structural material in many advanced applications, still posses the scientific and technological curiosity, mainly because of big scope in playing with its structure and hence attaining exortic properties. The recent development of nanomaterials, the so-called carbon nanostructures like carbon nanofibers, carbon nanotubes and carbon nanoparticles and the recent much talked grapheme have renewed interest in composites.  Amongst these, study of carbon nanotubes as such or as hybrid reinforcing material is one of the main areas of focus due to their combine mechanical and thermal characteristics. This involves synthesis of multiwall carbon nanotubes (MWCNTs) as such as well as on the surface of different substrates, which themselves are used as reinforcements. Varying the processing parameters one can control the length and orientation of carbon nanotubes. These variations in reinforcements affect the microstructure of the carbon matrix as well and Control of microstructure results in enhancement of properties of the carbon/carbon composites especially the thermal properties, oxidation resistance and fracture toughness.

题目2：Porous Carbons for General Purpose to High End Applications

报告人：Satish M. Manocha
        Department of Materials Science, Sardar Patel University
        Vallabh Vidya Nagar-388120, Gujarat, INDIA
        (sm_manocha@rediffmail.com)

摘要：Like solid carbons, porous carbons are also of great scientific and technological interest.  This class of carbons with relatively low density can have tailored porous network structures, permeability, thermal conductivity and other desired physical properties. As a result, these find applications both as adsorbents as well as filters, as insulators as well as conductors and so on. Their applications as adsorbants for water purification, environment control as well as  in ion exchange, catalysts  and  structural insulator materials are well known and have been exploited to the maximum. These varying properties of porous carbons are due to presence of pores which may be  interconnected or closed type. In addition to pore size, the pore- shape , pore volume and pore size distribution contribute to their  characteristics properties for a particular application.  Thus the need to create uniformity within the pore size, shape and volume enable the development of  materials  with superior properties. In our laboratory, variety of porous carbons have been synthesized using natural precursors as well as synthetic precursors. While natural precursors result in porous carbons with a wide range of pores, their surface area also gets limited. The pore sizes can be tailored to suit the end applications by suitably treating these precursors, especially thermosetting resins as carbon precursors and inorganics developed through sol-gel route as modifiers. In other sequences, template method and polymer blend methods were used to develop porous carbons with tailored pore structure. Aqueous silica sol, hydrolyzed silica and calcined silica as well as surfactant stabilized hydrolyzed and calcined silica were used as silica templates and PF resin was used as carbon precursor.  On pyrolysis and activation, such carbons exhibit pores in narrow range of 1 to 1. 2 nm. These were used to study adsorption of crypton and Xenon. Results showed that activated carbon having high surface area, high microporosity and associated with around 5% mesoporosity have high dynamic adsorption capacity for xenon. Details will be presented.