Sökning: "chemical fingerprint"

Visar resultat 1 - 5 av 17 avhandlingar innehållade orden chemical fingerprint.

  1. 1. Tracing and apportioning sources of dioxins using multivariate pattern recognition techniques

    Detta är en avhandling från Umeå : Umeå University

    Författare :Anteneh Assefa; Umeå universitet.; [2015]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; polychlorinated dibenzo-p-dioxin; polychlorinated dibenzofuran; positive matrix fac- torization; PMF; principal component analysis; PCA; Baltic Sea; sediment core; PCDD F; sources; marine; fish; environmental half-live; peak year; peak level; temporal trend; spatial variation; coastal; offshore; chemical fingerprint; Environmental Science; miljövetenskap;

    Sammanfattning : High levels of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) in edible fish in the Baltic Sea have raised health concerns in the Baltic region and the rest of Europe. Thus, there are urgent needs to characterize sources in order to formulate effective mitigation strategies. LÄS MER

  2. 2. Experimental and Computational Magnetic Resonance Studies of Selected Rare Earth and Bismuth Complexes

    Detta är en avhandling från Luleå University of Technology

    Författare :Vasantha Gowda; Luleå tekniska universitet.; [2017]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; Chemistry of Interfaces; Gränsytors kemi;

    Sammanfattning : The rare-earth elements (REEs) and bismuth, being classified as the ‘most critical raw materials’ (European Raw Materials Initiatives, 2017), have a high economic importance to the EU combined with a high relative supply risk. REEs are highly important for the evolving technologies such as clean-energy applications, high-technology components, rechargeable batteries, permanent magnets, electric and hybrid vehicles, and phosphors monitors. LÄS MER

  3. 3. The relationship between fly ash chemistry and the thermal formation of polychlorinated pollutants during waste incineration

    Detta är en avhandling från Umeå : Umeå universitet

    Författare :Duong Ngoc Chau Phan; Umeå universitet.; [2013]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Incinerations; dioxins; PCDD Fs; PCBs; PCNs; flue gas; fly ash; sampling; particle characterization; XPS; XRD; SEM EDX; formation; chlorination; PCA; OPLS; OPLS-DA;

    Sammanfattning : The thermal formation of polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), biphenyls (PCBs), and naphthalenes (PCNs) is a major problem in waste incineration. Ideally, rather than relying on air cleaning systems and treatment techniques, their formation should be minimized or, if possible eliminated. LÄS MER

  4. 4. Ash chemistry and fuel design focusing on combustion of phosphorus-rich biomass

    Detta är en avhandling från Umeå : Umeå universitet

    Författare :Nils Skoglund; Umeå universitet.; [2014]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; phosphorus; biomass; combustion; ash chemistry; fuel design; ash transformation; phosphorus-rich; ash-forming elements; fuel fingerprint; ash transformation reactions; Lewis base; Lewis acid; oorganisk kemi; Inorganic Chemistry;

    Sammanfattning : Biomass is increasingly used as a feedstock in global energy production. This may present operational challenges in energy conversion processes which are related to the inorganic content of these biomasses. As a larger variety of biomass is used the need for a basic understanding of ash transformation reactions becomes increasingly important. LÄS MER

  5. 5. Electronic structure investigations of transition metal complexes through X-ray spectroscopy

    Detta är en avhandling från Uppsala : Acta Universitatis Upsaliensis

    Författare :Meiyuan Guo; Uppsala universitet.; [2017]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; transition metal complexes; x-ray spectroscopy; electronic structures; Kemi; Chemistry;

    Sammanfattning : Catalysts based on the first-row (3d) transition metals are commonly seen in chemical and biological reactions. To understand the role of the transition metal in the catalyst, the element specific technique core level spectroscopy is used to probe the electronic structure and geometric properties centered around the metal site. LÄS MER