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Visar resultat 1 - 5 av 372 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Inductively Coupled Plasma Atomic Emission Spectrometry : Exploring the Limits of Different Sample Preparation Strategies

   Författare :Barbro Kollander; Jean Pettersson; Marit Andersson; Jonas Bergquist; Grethe Wibetoe; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; multi element analysis; trace element; ICP-AES; inductively coupled plasma atomic emission spectromtery; water analysis; liver analysis; non digested samples; medical samples; biological samples; samples from biopsies and autopsies; mice organ; fast analysis; internal standard; preconcentration; matrix elimination; Cu; Zn; Mn; Co; Pb; Cd; Mg; Ca; Fe; Ni; Cr; S; P; K; Al; Analytical chemistry; Analytisk kemi; Analytical Chemistry; Analytisk kemi;

   Sammanfattning : This thesis describes two different sample preparation strategies for inductively coupled plasma atomic emission spectrometry (ICP-AES), and their ability regarding multi element quantification in complex samples. Sensitivity, repeatability, reproducibility and accuracy were investigated. LÄS MER

3. 2. Bridge Monitoring to Allow for Reliable Dynamic FE Modelling : A Case Study of the New Årsta Railway Bridge

   Författare :Johan Wiberg; Håkan Sundquist; Raid Karoumi; Björn Paulsson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; bridge monitoring; FE modelling; signal analysis; torsion; warping; modulus of elasticity; natural frequency; damping; finite differences; Civil engineering and architecture; Samhällsbyggnadsteknik och arkitektur;

   Sammanfattning : Today’s bridge design work in many cases demands a trustworthy dynamic analysis instead of using the traditional dynamic amplification factors. In this thesis a reliable 3D Bernoulli-Euler beam finite element model of the New Årsta Railway Bridge was prepared for thorough dynamic analysis using in situ bridge monitoring for correlation. LÄS MER

4. 3. Interactions between Fe and organic matter and their impact on As(V) and P(V)

   Författare :Anneli Sundman; Per Persson; Thomas Borch; Umeå universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; XAS; Fe III ; As V ; P V ; natural organic matter; Fe II; III -NOM complexes; Krycklan catchment; Earth Sciences with Specialization Environmental Analysis; geovetenskap med inriktning mot miljöanalys;

   Sammanfattning : Iron (Fe) speciation is important for many biogeochemical processes. The high abundance and limited solubility of Fe(III) are responsible for the widespread occurrence of Fe(III) minerals in the environment. LÄS MER

5. 4. Warhead penetration in concrete protective structures

   Författare :Håkan Hansson; Anders Ansell; Mattias Unosson; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Warhead penetration; FE analysis; experiment; material modelling; fortifications; Stridsdelspenetration; FE-analyser; experiment; materialmodellering; fortifikationer;

   Sammanfattning : The analysis of penetration of warheads in concrete protective structures is an important part of the study of weapon effects on protective structures. This type of analysis requires that the design load in the form of a warhead is determined, and its characteristic and performance within a protective structure is known. LÄS MER

7. 5. Bridge Overhang Slabs with Edge Beams : LCCA and Structural Analysis for the Development of New Concepts

   Författare :José Javier Veganzones Muñoz; Costin Pacoste; Raid Karoumi; Lars Pettersson; Rui Vaz Rodrigues; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Overhang slab; Edge beam; Life-cycle Cost Analysis; Non-linear FE-analysis; Design methods; Shear force; Failure mode; Effective width; Minimal width.; Konsolplattor; Kantbalkar; Livscykelkostnadsanalys; Icke-linjär FE-analys; Dimensioneringsmetoder; Tvärkrafter; Brott; Fördelningsbredd; Minimal bredd.; Bro- och stålbyggnad; Structural Engineering and Bridges;

   Sammanfattning : Bridge edge beams are associated with high life-cycle costs because of the need of maintenance, which also causes traffic disturbances. For this reason, the Swedish Transport Administration started a project to find better solutions. One of the proposals was a design without edge beam. LÄS MER