DARK MATTER AND IT'S DETECTION AT TERRESTRIAL LABORATORIES

The work for this dissertation is two-fold, rst to understand the Standard Model(SM) and then looking for physics of Dark matter (DM) which is beyond the Standard model. We discuss Standard Model as a gauge theory where abelian and non-abelian gauge theory are thoroughly discussed. Then we move to electroweak sector where we discuss the interaction of intermediate vector bososns and fermions. Also we show how using Electroweak symmetry breaking and Higgs mechanism, we can give mass to SM particles. After this rst part we move to our second part which is DM physics. We derive the DM relic density in the expanding universe using Boltzmann equation. Then we concentrate our work on the direct detection of DM where we calculate the DM-nucleus scattering cross section, which is used in the terrestrial laboratories for the detection of DM

Air Pollution Problems and Control Measures in Steel Making Through Dri Route

© 2012 by World Scientific Publishing Co. Pte. Ltd. All rights reserved. The tremendous demand for steel and shortage of steel scrap in the world market boost the efforts to develop alternative steel-making process than the conventional blast furnace (BF) – basic oxygen furnace (BOF) route giving birth to directly reduced iron (DRI/sponge iron) process during the 1980s. The technological topics covered are pollution problems encountered, control measures, and enforcement mechanism adopted for sponge iron plants

Sulfonated Graphene-Nafion Composite Membranes for Polymer Electrolyte Fuel Cells Operating under Reduced Relative Humidity

Sulfonic acid-functionalized graphene (S-graphene) is employed as a promising inorganic filler as well as a solid acid proton conducting medium to realize a composite membrane with Nafion for polymer electrolyte fuel cell (PEFC) applications under reduced relative humidity (RH). The functionalization of graphene is performed by sulfonic acid-containing aryl radicals to increase the number of sulfonate groups per unit volume of a domain. A Nafion-S-graphene composite membrane is obtained by embedding S-graphene in Nafion, which provides high absorption of water and fast proton-transport across the electrolyte membrane under low RH values. The proton conductivity of the Nafion-S-graphene (1%) composite membrane at 20% RH is 17 mS cm-1, which is five times higher than that of a pristine recast Nafion membrane. PEFCs incorporating the Nafion-S-graphene composite membrane deliver a peak power density of 300 mW cm-2 at a load current density of 760 mA cm-2 while operating at optimum temperature of 70 °C under 20% RH and ambient pressure. By contrast, operating under identical conditions, a peak power density of 220 mW cm-2 is achieved with the pristine recast Nafion membrane. The Nafion-S-graphene composite membrane could be used to address many critical problems associated with commercial Nafion membranes in fuel cell applications. © 2016 American Chemical Society.

An experimental and simulation study of novel channel designs for open-cathode high-temperature polymer electrolyte membrane fuel cells

A minimum balance of plant (BOP) is desired for an open-cathode high temperature polymer electrolyte membrane (HTPEM) fuel cell to ensure low parasitic losses and a compact design. The advantage of an open-cathode system is the elimination of the coolant plate and incorporation of a blower for oxidant and coolant supply, which reduces the overall size of the stack, power losses, and results in a lower system volume. In the present study, we present unique designs for an open-cathode system which offers uniform temperature distribution with a minimum temperature gradient and a uniform flow distribution through each cell. Design studies were carried out to increase power density. An experimental and simulation approach was carried out to design the novel open-cathode system. Two unique parallel serpentine flow designs were developed to yield a low pressure drop and uniform flow distribution, one without pins and another with pins. A five-cell stack was fabricated in the lab based on the new design. Performance and flow distribution studies revealed better performance, uniform flow distribution, and a reduced temperature gradient across the stack; improving overall system efficiency. © 2015 Elsevier Ltd.