Prathap Haridoss

Bio: Prathap Haridoss is an academic researcher from Indian Institute of Technology Madras. The author has contributed to research in topics: Carbon nanotube & Proton exchange membrane fuel cell. The author has an hindex of 21, co-authored 61 publications receiving 1228 citations. Previous affiliations of Prathap Haridoss include Los Alamos National Laboratory & Plug Power.

Carbon Nanotubes and Nanohorn Hybrid Composite Buckypaper as Microporous Layer for Proton Exchange Membrane Fuel Cell

Abstract: In the present work, carbon nanotubes (CNT) and CNT-carbon nanohorns (CNH) (0, 30, 50, 70 and 100 wt.% CNH) composite Buckypapers (BPs) were fabricated using vacuum filtration technique. Structure and property relation of composite BPs were studied using scanning electron microscope, four probe technique, BET surface area and contact angle measurements. Properties such as electrical conductivity, hydrophobic nature and microstructure of CNT-30 wt.% CNH composite BP are superior to other composite BP. Hence, CNT-30 wt.% CNH composite BP is chosen as a microporous layer (MPL) for PEMFCs and tested in fuel cell testing fixture. Polarization studies reveal that the cells performance with composite BPs is comparable with SGL-MPL based cell. Hydrogen pumping and polarization studies of the cells confirms that composite BPs act as a good MPL at anode as well as cathode at 0.4 to 0.8 V. Hence, CNT-CNH composite BPs are potential candidates for PEMFC applications.

Multiwalled Carbon Nanotube Reinforced Epoxy Nanocomposites for Vibration Damping

Abstract: Multiwalled carbon nanotubes (CNTs) are used as reinforcement in epoxy modified with adduct, that is, block copolymer of carboxyl-terminated butadiene acrylonitrile (CTBN) and diglycidyl ether of bisphenol A (DGEBA). Microstructure analysis reveals uniform dispersion of a phase with spherical morphology in a continuous phase. The mean diameter of the spherical particles increased with CNT and adduct content. At 30 wt % adduct, adding CNTs results in exceptional growth of spherical particles. Loss factors in the first two modes were determined by using free vibration test in cantilever mode. Significant increase in loss factor is obtained for the epoxy nanocomposites modified with 30 wt % adduct and at all wt % CNTs (i.e., 0.5, 1, and 2.5). The vibration damping mechanism in this nanocomposite is likely due to the relative sliding of spherical particles during dynamic loads, which dissipates energy. The reduction in the distance between spherical particles as well as the reduction in the elastic modulus of...

I and i

Abstract: There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality. Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

Fast parallel algorithms for short-range molecular dynamics

Abstract: Three parallel algorithms for classical molecular dynamics are presented. The first assigns each processor a fixed subset of atoms; the second assigns each a fixed subset of inter-atomic forces to compute; the third assigns each a fixed spatial region. The algorithms are suitable for molecular dynamics models which can be difficult to parallelize efficiently—those with short-range forces where the neighbors of each atom change rapidly. They can be implemented on any distributed-memory parallel machine which allows for message-passing of data between independently executing processors. The algorithms are tested on a standard Lennard-Jones benchmark problem for system sizes ranging from 500 to 100,000,000 atoms on several parallel supercomputers--the nCUBE 2, Intel iPSC/860 and Paragon, and Cray T3D. Comparing the results to the fastest reported vectorized Cray Y-MP and C90 algorithm shows that the current generation of parallel machines is competitive with conventional vector supercomputers even for small problems. For large problems, the spatial algorithm achieves parallel efficiencies of 90% and a 1840-node Intel Paragon performs up to 165 faster than a single Cray C9O processor. Trade-offs between the three algorithms and guidelines for adapting them to more complex molecular dynamics simulations are also discussed.

American Society for Testing and Materials

Abstract: The American Society for Testing and Materials (ASTM) is an independent organization devoted to the development of standards.

Palladium-Based Electrocatalysts for Alcohol Oxidation in Half Cells and in Direct Alcohol Fuel Cells

Abstract: Direct alcohol fuel cells (DAFCs) are attracting increasing interest as power sources for portable applications due to some unquestionable advantages over analogous devices fed with hydrogen.1 Alcohols, such as methanol, ethanol, ethylene glycol, and glycerol, exhibit high volumetric energy density, and their storage and transport are much easier as compared to hydrogen. On the other hand, the oxidation kinetics of any alcohol are much slower and still H2-fueled polymer electrolyte fuel cells (PEMFCs) exhibit superior electrical performance as compared to DAFCs with comparable electroactive surface areas.2,3 Increasing research efforts are therefore being carried out to design and develop more efficient anode electrocatalysts for DAFCs.