Search for dissertations about: "Silver Clusters"

Showing result 1 - 5 of 11 swedish dissertations containing the words Silver Clusters.

2. 1. DESIREE: Instrumentation Developments and Hot Metal Cluster Decays

   Author : Emma K. Anderson; Henning Schmidt; Henrik Cederquist; Henning Zettergren; Oded Heber; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; DESIREE; microchannel plate; clusters; spontaneous decay; small metal cluster anions; silver; copper; gold; carbon dianions; fragmentation; vibrational autodetachment; DESIREE; mikrokanalplattor; kluster; spontana sönderfall; små metallklusteranjoner; silver; koppar; guld; kol di-anjoner; fragmentering; Physics; fysik;

   Abstract : This thesis presents instrumentation developments and measurements performed at the Double ElectroStatic Ion Ring ExpEriment, DESIREE, at Stockholm University. DESIREE operates at cryogenic temperatures ~13 K, with very low background pressures of ~10-14mbar, allowing the observation of stored ions to long times of tens of seconds and longer. READ MORE

4. 2. Lean NOx reduction over supported silver catalysts with methanol as reductant - Influence of silver loading, support material, hydrogen addition and C/N molar ratio

   Author : Marika Männikkö; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; hydrogen; silver loading; C N molar ratio; HC-SCR; lean NOx reduction; methanol; silver; alumina; ZSM-5;

   Abstract : The aim of this thesis is to find catalysts which show high activity and selectivity forlean NOx reduction in the low-temperature regime relevant for diesel and lean-burnengines and to investigate methanol as reducing agent. The lean NOx reduction oversupported silver catalysts is studied, focusing on the influence of the support material,silver loading, addition of hydrogen and the C/N molar ratio. READ MORE

5. 3. Dependence of the coordination number of silver(I) in crystalline halogenoargentates(I) on the nature of the cation

   Author : Göran Helgesson; Chalmers tekniska högskola; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; clusters; idioargentates I ; halogenocuprates I ; tetraphenylarsonium; crown ethers; tetranuclear; chloroargentates I ; bromoargentates I ; mononuclear; Halogenoargentates I ; heteronuclear; tetraethylammonium; dinuclear; cryptates; tetramethylammonium; crystal structure; silver I ;

   Abstract : .... READ MORE

6. 4. Free Metal Clusters Studied by Photoelectron Spectroscopy

   Author : Tomas Andersson; Olle Björneholm; Maxim Tchaplyguine; Paolo Piseri; Uppsala universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; clusters; nanoparticles; electronic structure; photoelectron spectroscopy; synchrotron radiation; surface segregation; nanoalloys; size-dependence; metallicity; plasmons; Physics with spec. in Atomic; Molecular and Condensed Matter Physics; Fysik med inriktning mot atom- molekyl- och kondenserande materiens fysik;

   Abstract : Clusters are aggregates of a finite number of atoms or molecules. In the present work, free clusters out of metallic parent materials have been created and studied by synchrotron radiation-based photoelectron spectroscopy. The clusters have been formed and studied in a beam and the electronic structure of the clusters has been investigated. READ MORE

7. 5. Silver Alumina Catalysts for Lean NOx Reduction - Influence of Preparation Methods and Type of Reductant, with Transient Kinetic Modelling

   Author : Hannes Kannisto; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; silver; kinetic modelling; Lean NOx reduction; sol-gel; preparation method; dispersion; cluster; HC-SCR; freeze-dry; XPS; alumina;

   Abstract : The objective of this work was to compare three different preparation methods for silver alumina catalysts for lean NOx reduction. Characteristics such as catalytic activity with propene and n-octane as reductants, chemical state of the silver and silver dispersion were analyzed. READ MORE