Search for dissertations about: "Seshadri constant"

Showing result 1 - 5 of 8 swedish dissertations containing the words Seshadri constant.

2. 1. Investigations of the Kinetics of Reduction and Reduction/Carburization of NiO-WO3 Precursors

   Author : Hesham M. Ahmed; Seshadri Seetharaman; Ricardo Morales Estrella; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Reduction; Reduction-Carburization; Gas-solid Reactions; Kinetics; Hydrogen; Methane; Thermogravimetric analysis; Fluidized bed; Simulation; Thermal diffusivity; Thermal conductivity; Laser flash; Metallurgical process engineering; Metallurgisk processteknik; Process Metallurgy;

   Abstract : Kinetic studies of reduction of the mixtures of NiO and WO3 having different Ni/(Ni+W) molar ratios in flowing hydrogen gas were investigated by means of Thermo Gravimetric Analysis (TGA), Fluidized Bed (FB) technique as well as Thermal diffusivity measurements under isothermal conditions. In the case of TGA, the reaction progress was monitored by mass loss, while evolved gas analysis by a gas chromatograph was the indicator of the reaction progress in the case of FB. READ MORE

4. 2. Thermodynamic investigations of transition metal systems containing coabon and nitrogen

   Author : Lidong Teng; Seshadri Seetharaman; Tooru Matsumiya; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Materials science; thermodynamic activity; galvanic cell technique; transition metal carbides; transition metal nitrides; phase equilibrium; Materialvetenskap; Materials science; Teknisk materialvetenskap;

   Abstract : In view of the important applications of carbides and carbo-nitrides of transition metals in the heat-resistant and hard materials industries, the thermodynamic activities of Cr and Mn in the Cr-C, Fe-Cr-C, Mn-Ni-C and Mn-Ni-C-N systems have been studied in the present work by the use of the galvanic cell technique. CaF2single crystals were used as the solid electrolyte. READ MORE

5. 3. Experimental Studies of Thermal Diffusivities concerning some Industrially Important Systems

   Author : Riad Abdul Abas; Seshadri Seetharaman; Rainer Wunderlich; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; laser flash; thermal diffusivity; heat conduction; phonon; electron contribution; crystallisation degree; graphitisation; Metallurgical process engineering; Metallurgisk processteknik;

   Abstract : The main objective of this industrially important work was to gain an increasing understanding of the properties of some industrially important materials such as CMSX-4 nickel base super alloy, 90Ti.6Al.4V alloy, 25Cr:6Ni stainless steel, 0. READ MORE

6. 4. Atomistic simulation and experimental studies of transition metal systems involving carbon and nitrogen

   Author : Jiaying Xie; Seshadri Seetharaman; Oleg Ostrovski; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Transition metal carbides; Transition metal nitrides; Transition metal carbo-nitrides; Lattice inversion method; Interatomic potential; Atomistic simulation; Metallurgical process engineering; Metallurgisk processteknik;

   Abstract : The present work was initiated to investigate the stability, structural and thermodynamic properties of transition metal carbides, nitrides and carbo-nitrides by atomistic simulations and experimentations. The interatomic pair potentials of Cr-Cr, Mn-Mn, Fe-Fe, C-C, Cr-C, Mn-C, Fe-C, Cr-Fe, Cr-N and Mn-N were inverted by the lattice inversion method and ab initio cohesive energies, and then employed to investigate the properties of Cr-, Mn- and Fe-carbides by atomistic simulations in this work. READ MORE

7. 5. Multipoint Okounkov bodies

   Author : Antonio Trusiani; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Seshadri constant; Okounkov body; Projective manifold; symplectic packings; Kähler geometry; ample line bundle;

   Abstract : During the nineties, the field medallist Okounkov found a way to associate to an ample line bundle L over an n−complex dimensional projective manifold X a convex body in Rn, now called Okounkov body ∆(L). The construction depends on the choice of a valuation centered at one point p∈X and it works even if L is a big line bundle. READ MORE