Sökning: "Transition metal"

Visar resultat 21 - 25 av 630 avhandlingar innehållade orden Transition metal.

  1. 21. Reactivity of Transition-Metal Compounds from Electronic Structure

    Författare :Aleksandra Vojvodic; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; magnetic edge states; electronic structure; density-functional theory; growth; surface states and resonances; nitrides; density of states; hydrodesulphurisation; sulphides; steam reforming; transition-metal carbides; Bronsted-Evans Polanyi relation; scaling relations; adsorption; descriptor; reactivity; catalysis;

    Sammanfattning : Transition-metal carbides (TMC's), nitrides, and sulfides belong to the class of materials known as transition-metal compounds (TMX's). Besides having intriguing properties, these materials are relevant for, e.g., growth and catalysis. LÄS MER

  3. 22. Magnetic properties of transition metal compounds and superlattices

    Författare :Arvid Broddefalk; Uppsala universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Materials science; Magnetic order; magnetocrystalline anisotropy; interlayer exchange coupling; transition metal compounds; superlattices; Materialvetenskap; Materials science; Teknisk materialvetenskap; Solid State Physics; fasta tillståndets fysik;

    Sammanfattning : Magnetic properties of selected compounds and superlattices have been experimentally studied using SQUID (superconducting quantum interference device) and VSM (vibrating sample magnetometer) magnetometry, neutron diffraction and Mössbauer spectroscopy measurements combined with theoretical ab initio calculations. The magnetic compounds (Fe1-xMx)3P, M=Co or Mn have been studied extensively. LÄS MER

  4. 23. Transition metal dissolution from Li-ion battery cathodes

    Författare :Yonas Tesfamhret; Reza Younesi; Erik J. Berg; Mark Huijben; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Lithium-ion battery; Lithium-ion cathode; Transition metal dissolution; Atomic Layer Deposition; Inductively coupled plasma atomic emission spectroscopy; Cathode-electrolyte interaction; Chemistry with specialization in Inorganic Chemistry; Kemi med inriktning mot oorganisk kemi;

    Sammanfattning : Lithium-ion batteries (LIBs) have become reliable electrochemical energy storage systems due to their relative high energy and power density, in comparison to alternative battery chemistries. The energy density of current LIBs is limited by the average operating voltage and capacity of oxide-based cathode materials containing a variety of transition metals (TM). LÄS MER

  5. 24. Optical properties of point defects in insulators and of transition metal dichalcogenides

    Författare :Christopher Linderälv; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; luminescence quenching; charge transition levels; excitons; transition metal dichalcogenides; monolayer alloys; solid state lighting; color centers; oxygen vacancies; moiré structures; wide band gap oxides;

    Sammanfattning : There is a need for new or modified materials, both to improve current devices and to create novel functionalities. Engineering materials to target specific functionalities requires a better understanding of how microscopic processes impact materials properties. LÄS MER

  7. 25. Transition metal and alloy catalysts in the light of computational materials modelling

    Författare :Ageo Meier de Andrade; Peter Broqvist; Jolla Kullgren; Elsebeth Schröder; Uppsala universitet; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; density functional theory; dispersion corrections; density functional analysis; transition metal; alloys; work function; lignin valorization; keto-enol tautomerization; Kemi med inriktning mot materialkemi; Chemistry with specialization in Materials Chemistry;

    Sammanfattning : This thesis is built around two pillars. One is heterogeneous catalysis in the broader context of green chemistry. The focus here is on identifying catalytically active materials suitable for the valorization of renewable feedstocks. LÄS MER