Search for dissertations about: "Density gradient"

Showing result 1 - 5 of 198 swedish dissertations containing the words Density gradient.

2. 1. Novel approaches for achieving full density powder metallurgy steels

   Author : Maheswaran Vattur Sundaram; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Cr- and Mo-alloyed PM steels; vacuum sintering; high density; full density; hot isostatic pressing.; cold isostatic pressing; liquid phase sintering; master alloy; double pressing-double sintering; powder metallurgy steels; sintering; water atomised powder;

   Abstract : Powder metallurgy (PM) is one of the most resource-efficient methods for manufacturing structural components with complex shapes. The utilisation of the metal powder to shape the components allows to minimise material waste and increase energy efficiency. READ MORE

4. 2. Airborne Gravity Gradient, Magnetic and VLF datasets : Case studies of modelling, inversion and interpretation

   Author : Sayyed Mohammad Abtahi; Thomas Kalscheuer; Laust Pedersen; Jochen Kamm; Thorkild Rasmussen; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; VLF; gravity gradient; magnetic; airborne; inversion; non-uniqueness;

   Abstract : Northern Sweden is one of the largest hosts for mineral resources in Europe and always has been an interesting area for researchers from various disciplines of Earth sciences. This dissertation is a comprehensive summary of three case study papers on airborne VLF, gravity gradient and magnetic data in the area. READ MORE

5. 3. Nonlocal Correlations in Density Functional Theory

   Author : Henrik Rydberg; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; bonding; GGA; adhesion; graphene; DFT; exchange; adsorption; LDA; first principles; polarization; vdW; determinants; correlation; graphite; surface states; van der Waals; density-functional theory; physisorption; nonlocal; functional;

   Abstract : In Density Functional Theory, the widely used local and semilocal approximations to the exchange-correlation energy, the local density approximation (LDA) and the generalized gradient approximations (GGAs), lack a physical description of truly nonlocal correlation effects, which are absolutely essential for a proper description of soft matter. A scheme is proposed that provides a basis for systematic improvements beyond LDA and GGA, including correlations at intermediate and long range, giving rise to bonds of pure van der Waals type as well as more intricate, intermediate-range correlation bonds. READ MORE

6. 4. On the compression properties of paper - implications for calendering

   Author : Peter Rättö; KTH; []
   Keywords : calendering; compression; creep; density; finite element analysis; heat transfer coefficient; mechanical properties; temperature; thermal conductivity; viscoelasticity; z-direction;

   Abstract : The objective of this work was to study and describe thedeformation of paper in the thickness direction in a calendernip that in some cases was heated. The temperature distributionin the thickness direction was evaluated using modelexperiments. READ MORE

7. 5. Experimental Investigations of Wave Motion and Electric Resistance in Collisionfree Plasmas

   Author : Martin Wendt; KTH; []
   Keywords : Beam-plasma; Buneman Instability; Density gradient; Double layer; Electric field measurement; Electron beam; Electrostatic eigenmode; Finite element; HF probe; PIC simulation; van der Pol oscillator;

   Abstract : .... READ MORE