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  • 101.
    Barreau, Lou
    et al.
    Department of Chemistry, University of California, Berkeley, California 94720, USA; Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
    Ross, Andrew D.
    Department of Chemistry, University of California, Berkeley, California 94720, USA; Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
    Kimberg, Victor
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Teoretisk kemi och biologi.
    Krasnov, Pavel
    International Research Center of Spectroscopy and Quantum Chemistry-IRC SQC, Siberian Federal University, Krasnoyarsk 660041, Russia.
    Blinov, Svyatoslav
    International Research Center of Spectroscopy and Quantum Chemistry-IRC SQC, Siberian Federal University, Krasnoyarsk 660041, Russia.
    Neumark, Daniel M.
    Department of Chemistry, University of California, Berkeley, California 94720, USA; Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
    Leone, Stephen R.
    Department of Chemistry, University of California, Berkeley, California 94720, USA; Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA; Department of Physics, University of California, Berkeley, California 94720, USA.
    Core-excited states of Formula Presented probed with soft-x-ray femtosecond transient absorption of vibrational wave packets2023Inngår i: Physical Review A: covering atomic, molecular, and optical physics and quantum information, ISSN 2469-9926, E-ISSN 2469-9934, Vol. 108, nr 1, artikkel-id 012805Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A vibrational wavepacket in Formula Presented is created by impulsive stimulated Raman scattering with a few-cycle infrared pulse and mapped simultaneously onto five sulfur core-excited states using table-top soft x-ray transient absorption spectroscopy between 170 to 200 eV. The femtosecond vibrations induce real-time energy shifts of the x-ray absorption, whose amplitude depend strongly on the nature of the core-excited state. The pump laser intensity is used to control the number of vibrational states in the superposition, thereby accessing core-excited levels for various extensions of the S-F stretching motion. This enables the determination of the relative core-level potential energy gradients for the symmetric stretching mode, in good agreement with TDDFT calculations. This experiment demonstrates a new means of characterizing core-excited potential energy curves.

  • 102.
    Baryshnikov, Gleb V.
    et al.
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi. Tomsk State University, Russian Federation.
    Valiev, Rashid R.
    Minaev, Boris F.
    Ågren, Hans
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi. Siberian Federal University, Russian Federation.
    Optical tuning of tetrabenzo[8]circulene derivatives through pseudorotational conformational isomerization2018Inngår i: Dyes and pigments, ISSN 0143-7208, E-ISSN 1873-3743, Vol. 151, s. 372-379Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In order to further search efficient [8]circulene materials for OLED applications we have theoretically investigated the structure and electronic, absorption spectra of functionalized tetrabenzo[8]circulenes with different substituents in the outer perimeter. These hydrocarbon materials complement the wide family of [8]circulenes which earlier have been demonstrated to possess promising emissive and exciplex-forming properties suitable for organic light emitting diodes. The hydrocarbon tetrabenzo[8]circulenes show saddle shape of the molecular skeleton which can exist in two different conformations with different curvatures of the macrocycle. The aromaticity, electronic structure and orbital pattern are found to be principally different for these two isomers, where the global minimum isomer is weakly antiaromatic and electronically less stable comparing with the non-aromatic local minimum structure. The absorption spectra are also very different: the global minimum structure is more active in the long-wavelength region while the local minimum isomer shows absorption only at short wavelengths. Our computational findings suggest a new concept for optical tuning of curved [8]circulenes through conformational isomerization and aromaticity control, thus through structural variations without changing the molecular composition. Based on this principle we have designed novel functionalized [8]circulenes with promising fluorescence activity.

  • 103.
    Baryshnikov, Glib V.
    et al.
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi.
    Minaeva, Valentina A.
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi.
    Minaev, Boris F.
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi.
    Grigoras, M.
    The Electronic Structure and Spectra of Triphenylamines Functionalized by Phenylethynyl Groups2018Inngår i: Optics and Spectroscopy, ISSN 0030-400X, E-ISSN 1562-6911, Vol. 124, nr 1, s. 57-64Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We study the features of the electronic structure and the IR, UV, and visible spectra of a series of triphenylamines substituted with phenylethynyl groups. The analysis is performed at the level of the density functional theory (DFT) and its nonstationary version in comparison with the experimental data of IR and electron spectroscopy. It is shown that, in the excited state, there is a change in the alternation of single, double, and triple bonds in accordance with the character of bonding and antibonding in the lowest vacant molecular orbital. The gradual introduction of additional phenylethynyl groups does not cause frequency shifts in the IR spectra of the molecules under study, but significantly affects the intensity of the corresponding IR bands. A similar effect is also observed in the electronic-absorption spectra of these compounds. This can be used for optical tuning of triphenylamines as promising materials for organic light-emitting diodes and solar cells.

  • 104.
    Basumatary, I. B.
    et al.
    Department of Food Engineering and Technology, Central Institute of Technology Kokrajhar, Kokrajhar 783370, Assam, India.
    Mukherjee, A.
    Department of Food Engineering and Technology, Central Institute of Technology Kokrajhar, Kokrajhar 783370, Assam, India.
    Katiyar, V.
    Department of Chemical Engineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India.
    Kumar, S.
    Department of Food Engineering and Technology, Central Institute of Technology Kokrajhar, Kokrajhar 783370, Assam, India.
    Dutta, Joydeep
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Material- och nanofysik.
    Chitosan-based antimicrobial coating for improving postharvest shelf life of pineapple2021Inngår i: Coatings, ISSN 2079-6412, Vol. 11, nr 11, artikkel-id 1366Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Rapid postharvest losses and quality deteriorations in pineapple are major challenges to growers and handlers. Chitosan-based coatings on fruit surfaces have gained importance in recent years to enhance postharvest shelf life of the fruits. In this study, aloe vera gel was added as a natural antioxidant in chitosan-based composite coating containing ZnO nanoparticles. The developed formulation was applied on the surface of freshly harvested pineapple fruits. ZnO nanoparticles were used as an antimicrobial agent. Coated pineapple fruits were evaluated for weight loss, total soluble solids, titratable acidity, decay index, maturity index, and sensory attributes, including visual appearance, periodically at 5 day interval during storage. The results showed that the coating of the fruit reduced weight loss by about 5%, and also delayed ripening and oxidative decay compared to the uncoated fruit. Thus, the developed coating formulation is a promising sustainable solution to reduce postharvest losses and to extend shelf life of pineapples.

  • 105.
    Basumatary, Indra Bhusan
    et al.
    Cent Inst Technol Kokrajhar, Dept Food Engn & Technol, Kokrajhar 783370, Assam, India..
    Mukherjee, Avik
    Cent Inst Technol Kokrajhar, Dept Food Engn & Technol, Kokrajhar 783370, Assam, India..
    Katiyar, Vimal
    Indian Inst Technol Guwahati, Dept Chem Engn, Gauhati 781039, Assam, India..
    Dutta, Joydeep
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Material- och nanofysik.
    Kumar, Santosh
    Cent Inst Technol Kokrajhar, Dept Food Engn & Technol, Kokrajhar 783370, Assam, India..
    Chitosan-based active coating for pineapple preservation: Evaluation of antimicrobial efficacy and shelf-life extension2022Inngår i: Lebensmittel-Wissenschaft + Technologie, ISSN 0023-6438, E-ISSN 1096-1127, Vol. 168, s. 113940-, artikkel-id 113940Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Pineapple is a tropical fruit that is the most economically significant member of the Bromeliaceae family that are rich in flavonoids, phenolic acids, and antioxidants, which protect human cells from free radicals known to cause chronic diseases. However, short postharvest shelf-life of the fruit limits its long-distance distribution and consumption. Chitosan is a positively charged polysaccharide consisting of N-acetyl D-glucosamine and D-glucosamine units that can be used as a promising sustainable biopolymer for active coating of the fruit. In this work, chitosan-based nanocomposite formulations were prepared with added eugenol (clove essential oil) and Aloe vera gel as antioxidant, antibacterial and antifungal agents. The results showed that the incorporation of eugenol oil nanoemulsion and Aloe vera gel in the coatings enhanced their physico-chemical and functional properties including antimicrobial activities against four foodborne bacterial pathogens (Escherichia coli, Alcaligenes faecalis, Staphylococcus aureus, and Bacillus subtilis) and two fungal isolates. The developed coatings not only kept the pineapple fresh, but also preserved its quality and prolonged their shelf-life by up to three weeks during storage in ambient conditions.

  • 106.
    Bauer, Paul
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Beräknings- och systembiologi.
    Barrozo, Alexandre
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Struktur- och molekylärbiologi.
    Amrein, Beat Anton
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Struktur- och molekylärbiologi.
    Purg, Miha
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Struktur- och molekylärbiologi.
    Esguerra, Mauricio
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Beräkningsbiologi och bioinformatik.
    Wilson, Philippe
    De Montfort University Leicester, School of Pharmacy .
    Åqvist, Johan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Beräkningsbiologi och bioinformatik.
    Major, Dan Thomas
    Department of Chemistry, The Lise Meitner-Minerva Center of Computational Quantum Chemistry, Bar-Ilan University, Ramat-Gan 52900, Israel.
    Kamerlin, Shina Caroline Lynn
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Struktur- och molekylärbiologi.
    Q Version 6, a comprehensive toolkit for empirical valence bond and related free energy calculations.Manuskript (preprint) (Annet vitenskapelig)
  • 107.
    Bedin, Michele
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Molekylär biomimetik.
    Ericsson, Tore ()
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Materialfysik.
    Häggström, Lennart
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Materialfysik.
    Valvo, Mario
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
    Ott, Sascha
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Molekylär biomimetik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Syntetisk molekylär kemi.
    Thapper, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Molekylär biomimetik.
    A diiron complex as a structural model of Class 1a Robonucleotide ReductaseInngår i: Artikkel i tidsskrift (Fagfellevurdert)
  • 108.
    Bedin, Michele
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström. Uppsala University.
    Thapper, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Molekylär biomimetik.
    A dinuclear manganese complex with an asymmetric ligand as a functional mimic of manganese catalaseInngår i: Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Reactive Oxygen Species (ROS) in the form of H2O2, OH radicals, and superoxide, are oxygen species generated in the respiratory chain. In high concentrations, these species can cause pathological conditions like ischemia-reperfusion related injuries and neurodegenerative diseases. A series of enzymes exists in nature to protect from this danger: superoxide dismutases (SOD), glutathione peroxidases (GSH), and catalases (CAT). The catalases catalyse the decomposition of H2O2 into water and molecular oxygen.  In this work, we focus on mimicking the MnCAT, a subclass of CAT that contains two Mn ions in the cofactor. An asymmetric and dinucleating ligand H2DPCPMP (2-(N-(3-((bis((pyridin-2-yl)methyl)amino)methyl)-2-hydroxy-5-methylbenzyl)-N-((pyridin-2-yl)methyl)amino acetic acid) that contains three pyridine groups, one carboxylate group, and one phenol was used. The ligand can create two pockets where two Mn ions can be accommodated. The dimanganese complex of H2DPCPMP was synthesized and characterized with mass spectrometry, electrochemistry, IR, UV-vis and EPR. The complex can act as a catalyst for the disproportionation of H2O2 but unlike many previously reported mimics of MnCAT, the rate of oxygen evolution is not saturated at high concentrations of H2O2

  • 109.
    Belfrage, Anna Karin
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Avdelningen för organisk farmaceutisk kemi.
    Design and Synthesis of Hepatitis C Virus NS3 Protease Inhibitors: Targeting Different Genotypes and Drug-Resistant Variants2015Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Since the first approved hepatitis C virus (HCV) NS3 protease inhibitors in 2011, numerous direct acting antivirals (DAAs) have reached late stages of clinical trials. Today, several combination therapies, based on different DAAs, with or without the need of pegylated interferon-α injection, are available for chronic HCV infections. The chemical foundation of the approved and late-stage HCV NS3 protease inhibitors is markedly similar. This could partly explain the cross-resistance that have emerged under the pressure of NS3 protease inhibitors. The first-generation NS3 protease inhibitors were developed to efficiently inhibit genotype 1 of the virus and were less potent against other genotypes.

    The main focus in this thesis was to design and synthesize a new class of 2(1H)-pyrazinone based HCV NS3 protease inhibitors, structurally dissimilar to the inhibitors evaluated in clinical trials or approved, potentially with a unique resistance profile and with a broad genotypic coverage. Successive modifications were performed around the pyrazinone core structure to clarify the structure-activity relationship; a P3 urea capping group was found valuable for inhibitory potency, as were elongated R6 residues possibly directed towards the S2 pocket. Dissimilar to previously developed inhibitors, the P1’ aryl acyl sulfonamide was not essential for inhibition as shown by equally good inhibitory potency for P1’ truncated inhibitors. In vitro pharmacokinetic (PK) evaluations disclosed a marked influence from the R6 moiety on the overall drug-properties and biochemical evaluation of the inhibitors against drug resistant enzyme variants showed retained inhibitory potency as compared to the wild-type enzyme. Initial evaluation against genotype 3a displayed micro-molar potencies. Lead optimization, with respect to improved PK properties, were also performed on an advanced class of HCV NS3 protease inhibitors, containing a P2 quinazoline substituent in combination with a macro-cyclic proline urea scaffold with nano-molar cell based activities.

    Moreover, an efficient Pd-catalyzed C-N urea arylation protocol, enabling high yielding introductions of advanced urea substituents to the C3 position of the pyrazinone, and a Pd-catalyzed carbonylation procedure, to obtain acyl sulfinamides, were developed. These methods can be generally applicable in the synthesis of bioactive compounds containing peptidomimetic scaffolds and carboxylic acid bioisosteres.

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  • 110.
    Ben Dkhil, Sadok
    et al.
    Aix Marseille University, France.
    Gaceur, Meriem
    Aix Marseille University, France.
    Karim Diallo, Abdou
    Aix Marseille University, France.
    Didane, Yahia
    Aix Marseille University, France.
    Liu, Xianjie
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ytors Fysik och Kemi. Linköpings universitet, Tekniska fakulteten.
    Fahlman, Mats
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ytors Fysik och Kemi. Linköpings universitet, Tekniska fakulteten.
    Margeat, Olivier
    Aix Marseille University, France.
    Ackermann, Jorg
    Aix Marseille University, France.
    Videlot-Ackermann, Christine
    Aix Marseille University, France.
    Reduction of Charge-Carrier Recombination at ZnO Polymer Blend Interfaces in PTB7-Based Bulk Heterojunction Solar Cells Using Regular Device Structure: Impact of ZnO Nanoparticle Size and Surfactant2017Inngår i: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 9, nr 20, s. 17257-17265Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Cathode interfacial layers, also called electron extraction layers (EELs), based on zinc oxide (ZnO) have been studied in polymer-blend solar cells toward optimization of the opto-electric properties. Bulk heterojunction solar cells based on poly( {4, 8-bis [(2- ethylhexyl) oxy]b enzo [1,2- b :4,5-b dithiophene-2,6-diyl}{3-fluoro-2-[(2-ethylhexyl)carbonyl]- thieno[3,4-b]thiophenediy1}) (PTB7) and [6,6]-phenyl-C71-butyric acid methyl ester (PC70BM) were realized in regular structure with all-solution-processed interlayers. A pair of commercially available surfactants, ethanolamine (EA) and ethylene glycol (EG), were used to modify the surface of ZnO nanoparticles (NPs) in alcohol-based dispersion. The influence of ZnO particle size was also studied by preparing dispersions of two NP diameters (6 versus 11 nm). Here, we show that performance improvement can be obtained in polymer solar cells via the use of solution-processed ZnO EELs based on surface-modified nanoparticles. By the optimizing of the ZnO dispersion, surfactant ratio, and the resulting morphology of EELs, PTB7/PC70BM solar cells with a power-conversion efficiency of 8.2% could be obtained using small sized EG-modified ZnO NPs that allow the clear enhancement of the performance of solution processed photovoltaic devices compared to state-of-the-art ZnO-based cathode layers.

  • 111.
    Benavente, Veronica
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Lage, Sandra
    Department of Forest Biomaterials and Technology, Swedish University of Agricultural Sciences, Umeå, Sweden; Department of Environmental Science, Stockholm University, Stockholm, Sweden.
    Gentili, Francesco G.
    Department of Forest Biomaterials and Technology, Swedish University of Agricultural Sciences, Umeå, Sweden.
    Jansson, Stina
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Influence of lipid extraction and processing conditions on hydrothermal conversion of microalgae feedstocks – Effect on hydrochar composition, secondary char formation and phytotoxicity2022Inngår i: Chemical Engineering Journal, ISSN 1385-8947, E-ISSN 1873-3212, Vol. 428, artikkel-id 129559Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This study investigated the effect of lipid extraction of microalgae feedstocks subjected to hydrothermal carbonization (HTC) with regard to the carbonization degree, chemical composition and phytotoxicity of hydrochars produced under different reaction temperatures and residence times. Special attention was given to the formation and composition of secondary char, as this part of the hydrochar may be of particular importance for environmental and technical applications. A microalgae polyculture grown in municipal wastewater was extracted to retrieve lipids, and both unextracted (MA) and extracted microalgae (EMA) were used to produce hydrochars at 180–240 °C for 1–4 h. The composition of the hydrochars was thoroughly characterized by elemental analysis, thermogravimetric analysis and pyrolysis–gas chromatography/mass spectrometry analysis. MA exhibited a greater carbonization degree than EMA and contained higher amounts of secondary char under the same processing conditions. During the carbonization of EMA, more decomposition products remained in the liquid phase and less polymerization occurred than for MA, which explained the lower solid yield of EMA-derived hydrochars in comparison to MA hydrochars. Consequently, although they contained potentially toxic substances (i.e., carboxylic acids, aldehydes and ketones), the EMA-derived hydrochars exhibited a lower phytotoxic potential. This indicates that low-temperature hydrochars containing less than 10% of extractives might be suitable as soil amendments, whereas extractive-rich hydrochars would be more appropriate for other long-term applications, such as adsorbents for contaminant removal, energy storage and composite materials. Detailed characterization of microalgae-derived hydrochars is required to enable the most suitable application areas to be identified for these materials, and thereby make full use of their function as carbon sinks.

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  • 112.
    Benavente, Veronica
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen. RISE Processum AB, Hörneborgsvägen 10, Örnsköldsvik, Sweden.
    Pérez, Carla
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen. Industrial Doctoral School, Umeå University, Umeå, Sweden.
    Jansson, Stina
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Co-hydrothermal carbonization of microalgae and digested sewage sludge: Assessing the impact of mixing ratios on the composition of primary and secondary char2024Inngår i: Waste Management, ISSN 0956-053X, E-ISSN 1879-2456, Vol. 174, s. 429-438Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The role of microalgae cultivation in wastewater treatment and reclamation has been studied extensively, as has the potential utility of the resulting algal biomass. Most methods for processing such biomass generate solid residues that must be properly managed to comply with current sustainable resource utilization requirements. Hydrothermal carbonization (HTC) can be used to process both individual wet feedstocks and mixed feedstocks (i.e., co-HTC). Here, we investigate co-HTC using microalgae and digested sewage sludge as feedstocks. The objectives were to (i) study the material's partitioning into solid and liquid products, and (ii) characterize the products’ physicochemical properties. Co-HTC experiments were conducted at 180–250°C using mixed microalgae/sewage sludge feedstocks with the proportion of sewage sludge ranging from 0 to 100 %. Analyses of the hydrochar composition and the formation and composition of secondary char revealed that the content of carbonized material in the product decreased as the proportion of sewage sludge in the feedstock increased under fixed carbonization conditions. The properties of the hydrochars and the partitioning of material between the liquid phase and the hydrochar correlated linearly with the proportion of microalgae in mixed feedstocks, indicating that adding sewage sludge to microalgae had weak or non-existent synergistic effects on co-HTC outcomes. However, the proportion of sewage sludge in the feedstock did affect the secondary char. For example, adding sewage sludge reduced the abundance of carboxylic acids and ketones as well as the concentrations of higher molecular weight cholesterols. Such changes may alter the viable applications of the hydrochar.

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  • 113.
    Benedek, Peter
    et al.
    Swiss Fed Inst Technol, Dept Informat Technol & Elect Engn, CH-8092 Zurich, Switzerland..
    Yazdani, Nuri
    Swiss Fed Inst Technol, Dept Informat Technol & Elect Engn, CH-8092 Zurich, Switzerland..
    Chen, Hungru
    Univ Bath, Dept Chem, Bath BA2 7AY, Avon, England..
    Wenzler, Nils
    Swiss Fed Inst Technol, Dept Informat Technol & Elect Engn, CH-8092 Zurich, Switzerland..
    Juranyi, Fanni
    Paul Scherrer Inst, Lab Neutron Scattering & Imaging, CH-5232 Villigen, Switzerland..
    Månsson, Martin
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Material- och nanofysik.
    Islam, M. Saiful
    Univ Bath, Dept Chem, Bath BA2 7AY, Avon, England..
    Wood, Vanessa C.
    Swiss Fed Inst Technol, Dept Informat Technol & Elect Engn, CH-8092 Zurich, Switzerland..
    Surface phonons of lithium ion battery active materials2019Inngår i: Sustainable Energy & Fuels, E-ISSN 2398-4902, Vol. 3, nr 2, s. 508-513Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Surfaces of active materials are understood to play an important role in the performance and lifetime of lithium-ion batteries, but they remain poorly characterized and therefore cannot yet be systematically designed. Here, we combine inelastic neutron scattering and ab initio simulations to demonstrate that the structure of the surface of active materials differs from the interior of the particle. We use LiFePO4 (LFP) as a model system, and we find that carbon coating influences the Li-O bonding on the (010) LFP surface relative to the bulk. Our results highlight how coatings can be used to systematically engineer the vibrations of atoms at the surface of battery active materials, and thereby impact lithium ion transport, charge transfer, and surface reactivity.

  • 114.
    Bengtsson, Katarina
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Ytors Fysik och Kemi. Linköpings universitet, Tekniska fakulteten.
    Electrokinetic devices from polymeric materials2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    There are multiple applications for polymers: our bodies are built of them, plastic bags and boxes used for storage are composed of them, as are the shells for electronics, TVs, computers, clothes etc. Many polymers are cheap, and easy to manufacture and process which make them suitable for disposable systems. The choice of polymer to construct an object will therefore highly influence the properties of the object itself. The focus of this thesis is the application of commonly used polymers to solve some challenges regarding integration of electrodes in electrokinetic devices and 3D printing.

    The first part of this thesis regards electrokinetic systems and the electrodes’ impact on the system. Electrokinetic systems require Faradaic (electrochemical) reactions at the electrodes to maintain an electric field in an electrolyte. The electrochemical reactions at the electrodes allow electron-to-ion transduction at the electrode-electrolyte interface, necessary to drive a current at the applied potential through the system, which thereby either cause flow (electroosmosis) or separation (electrophoresis). These electrochemical reactions at the electrodes, such as water electrolysis, are usually problematic in analytical systems and systems applied in biology. One solution to reduce the impact of water electrolysis is by replacing metal electrodes with electrochemically active polymers, e.g. poly(3,4-ethylenedioxythiophene) (PEDOT). Paper 1 demonstrates that PEDOT electrodes can replace platinum electrodes in a gel electrophoretic setup. Paper 2 reports an all-plastic, planar, flexible electroosmotic pump which continuously transports water from one side to the other using potentials as low as 0.3 V. This electroosmotic pump was further developed in paper 3, where it was made into a compact and modular setup, compatible with commercial microfluidic devices. We demonstrated that the pump could maintain an alternating flow for at least 96 h, with a sufficient flow of cell medium to keep cells alive for the same period of time.

    The second part of the thesis describes the use of 3D printers for manufacturing prototypes and the material requirements for 3D printing. Protruding and over-hanging structures are more challenging to print using a 3D printer and usually require supporting material during the printing process. In paper 4, we showed that polyethylene glycol (PEG), in combination with a carbonate-based plasticizer, functions well as a 3D printable sacrificial template material. PEG2000 with between 20 and 30 wt% dimethyl carbonate or propylene carbonate have good shear-thinning rheology, mechanical and chemical stability, and water solubility, which are advantageous for a supporting material used in 3D printing.

    The advances presented in this thesis have solved some of the challenges regarding electrokinetic systems and prototype manufacturing. Hopefully this will contribute to the development of robust, disposable, low-cost, and autonomous electrokinetic devices.

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  • 115.
    Benselfelt, Tobias
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Fiberteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Nordenström, Malin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Fiberteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Hamedi, Mahiar
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Fiberteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Wågberg, Lars
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Fiberteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Ion-induced assemblies of highly anisotropic nanoparticles are governed by ion-ion correlation and specific ion effects2019Inngår i: Nanoscale, ISSN 2040-3364, E-ISSN 2040-3372, Vol. 11, nr 8, s. 3514-3520Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Ion-induced assemblies of highly anisotropic nanoparticles can be explained by a model consisting of ion-ion correlation and specific ion effects: dispersion interactions, metal-ligand complexes, and local acidic environments. Films of cellulose nanofibrils and montmorillonite clay were treated with different ions, and their subsequent equilibrium swelling in water was related to important parameters of the model in order to investigate the relative importance of the mechanisms. Ion-ion correlation was shown to be the fundamental attraction, supplemented by dispersion interaction for polarizable ions such as Ca2+ and Ba2+, or metal-ligand complexes for ions such as Cu2+, Al3+ and Fe3+. Ions that form strong complexes induce local acidic environments that also contribute to the assembly. These findings are summarized in a comprehensive semi-quantitative model and are important for the design of nanomaterials and for understanding biological systems where specific ions are involved.

  • 116.
    Berg, C. Anders R.
    Umeå universitet, Fakultet för lärarutbildning, Matematik, teknik och naturvetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Factors related to observed attitude change toward learning chemistry among university students2005Inngår i: Chemistry Education Research and Practice, E-ISSN 1756-1108, Vol. 6, nr 1, s. 1-18Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    To gain insight into factors associated with changes in attitude toward learning chemistry, six students who displayed major attitude changes were identified through a pre- and post-course attitude questionnaire administered to sixty-six first-year university chemistry students. Those with largest attitude changes, both positive and negative, were selected to highlight the contrast between students. The six students were interviewed; descriptions of their one-semester chemistry course experiences were analyzed to identify factors associated with their change in attitude. A positive attitude change was associated with evidence of motivated behaviour, while a negative change was linked to less motivated behaviour. Students addressed similar factors in the educational setting, but students with positive attitude changes exhibited fewer negative views of educational factors, while students with negative attitude changes showed an opposite pattern. Since the same factors, students’ perceived level of teacher empathy for their efforts at chemistry learning, affected both groups, this indicates a possibility for changes in educational setting beneficial to all students.

  • 117.
    Bergenstrahle-Wohlert, Malin
    et al.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi. KTH, Skolan för kemivetenskap (CHE), Centra, Wallenberg Wood Science Center.
    Wohlert, Jakob
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi. KTH, Skolan för kemivetenskap (CHE), Centra, Wallenberg Wood Science Center.
    Vibrational spectrum of the cellulose-water interface investigated by atomistic simulations2014Inngår i: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 247, s. 190-CELL-Artikkel i tidsskrift (Annet vitenskapelig)
  • 118.
    Berger, Patricia Sara
    et al.
    Procter & Gamble Company.
    Song, Brian Xiaoqing
    Procter & Gamble Company.
    Schwartz, James Robert
    Procter & Gamble Company.
    Corkery, Robert W.
    Procter & Gamble Company.
    Methods for treating glassware surfaces using corrosion protection agents.2004Patent (Annet (populærvitenskap, debatt, mm))
    Abstract [en]

    A domestic, institutional, industrial, and/or com. method of reducing glassware surface corrosion in an automatic dishwashing appliance comprises the step of contacting a glassware surface with a corrosion protection agent comprising: (a) an effective amt. of a zinc-contg. layered material, said material having a particle size in the range of about 1 nm to about 100 nm and a crystallinity value of from about 0.4 to about 0.8625 FWHM units, at a 200 reflective peak; and (b) optionally, an adjunct ingredient and (c) a dispersant polymer: said contacting being done at a pH greater than 9 to about 14. Methods using corrosion protection agents that form a part of a treatment system and/or are incorporated in a compn. of matter are also provided. [on SciFinder(R)]

  • 119.
    Berger, Patricia Sara
    et al.
    Procter & Gamble Company.
    Song, Brian Xiaoqing
    Procter & Gamble Company.
    Schwartz, James Robert
    Procter & Gamble Company.
    Corkery, Robert William.
    Procter & Gamble Company.
    Zinc corrosion protection agents for treating glassware surfaces2006Patent (Annet (populærvitenskap, debatt, mm))
    Abstract [en]

    Corrosion protection agents for treating glassware surfaces, for example dishes and glasses, esp. corrosion protection agents comprising zinc-contg. materials are provided. Treatment systems and compn. of matter, which incorporate these corrosion protection agents, are also provided. [on SciFinder(R)]

  • 120. Berggren, D.
    et al.
    Bertling, Sofia
    KTH, Tidigare Institutioner (före 2005), Materialvetenskap.
    Heijerick, D.
    Herting, Gunilla
    KTH, Tidigare Institutioner (före 2005), Materialvetenskap.
    Koundakjian, P.
    Leygraf, Christofer
    KTH, Tidigare Institutioner (före 2005), Materialvetenskap.
    Odnevall Wallinder, Inger
    KTH, Tidigare Institutioner (före 2005), Materialvetenskap.
    Release of Chromium, Nickel and Iron from Stainless Steel Exposed under Atmospheric Conditions and The Environmental Interaction of these Metals: A Combined Field and Laboratory Investigation2004Rapport (Annet vitenskapelig)
  • 121.
    Bergius, Lina
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för tillämpad fysik och elektronik.
    Sulfatmätningar i kokeriet2015Independent thesis Basic level (university diploma), 5 poäng / 7,5 hpOppgave
    Abstract [sv]

    Arbetet har mestadels utförts i kokeriet på Domsjö Fabriker i syfte att kartlägga hur processförhållandena hänger samman med koncentrationen sulfatjoner. Detta för att lättare kunna undvika förhållanden i processen som innebär mycket höga värden. Arbetet ingår i examen för högskoleutbildningen: processoperatör vid Umeå Universitet.Vid Domsjö Fabriker har tidigare liknande mätningar gjorts i kokeriet och det har konstaterats att koncentrationen sulfatjoner hänger samman med pH och tid. Syftet är att djupare kartlägga hur processförhållandena hänger samman för att lättare kunna undvika förhållanden som innebär höga koncentrationer sulfatjoner. Målet med examensarbetet och dess undersökning är att sammanställa resultat som visar hur och när under koket som sulfatjoner bildas i stora mängder i kokeriet. Förfarandet av undersökningen har bestått i att prov tas ut i provserier om fyra provtillfällen per kok, fryses in och slutligen analyseras genom titrering och pH-mätning.Efter totalt 22 stycken provserier om fyra prov från de olika kokarna konstaterades att sulfatkoncentrationen är högst i slutet av nedgasningssteget. Det första provtillfället hade de högsta pH-värdena men också de lägsta koncentrationerna sulfat. Inget av dessa värden sticker ur och anses onormalt på något sätt. Om sulfatkoncentrationen påverkas av pH-värdet går inte att fastställa av detta arbete, då det inte är de lägsta pH-värdena som genererar de högsta sulfatkoncentrationerna utifrån resultatet i undersökningen.

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  • 122.
    Berglund, Per
    et al.
    KTH, Skolan för bioteknologi (BIO), Biokemi.
    Svedendahl Humble, Maria
    Branneby, Cecilia
    7.18 C-X Bond Formation: Transaminases as Chiral Catalysts: Mechanism, Engineering, and Applications2012Inngår i: Comprehensive Chirality, Elsevier, 2012, Vol. 7, s. 390-401Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    Enantiomerically pure amines and amino acids are important building blocks in academic research as well as in industrial-scale chemical production. Transaminases are versatile enzymes providing access to such compounds of high enantiomeric excess. This chapter illustrates the available strategies with transaminases such as kinetic resolution or stereoselective synthesis and highlights many successful examples for amino acid and chiral amines synthesis. There are some known challenges linked to the use of transaminases, for example in terms of unfavorable equilibria and inhibition. Several successful examples to overcome these limitations are presented. Also, the classification of transaminases, mechanistic details, and various strategies for optimization are discussed.

  • 123. Bergman, Susanna
    et al.
    Dahlin, Sandra
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Processteknologi.
    Mesilov, Vitaly
    Xiao, Yang
    Englund, Johanna
    Xi, Shibo
    Tang, Chunhua
    Skoglundh, Magnus
    Pettersson, Lars
    Bernasek, Steven
    In-situ studies of oxidation/reduction of copper in Cu-CHA SCR catalysts:comparison of fresh and SO2-poisoned catalystsInngår i: Artikkel i tidsskrift (Annet vitenskapelig)
    Abstract [en]

    SO2-poisoning results in deactivation of Cu-CHA SCR under standard SCR conditions; however regeneration at 700 ◦C completely restores the SCR performance. To understand the nature of these effects, Cu-species in the fresh and poisoned catalystswere characterized by in-situ temperature-dependent time-resolved Cu K-edge X-ray absorption spectroscopy using the multivariate curve resolution alternating least squares (MCR-ALS) approach and continuous Cauchy wavelet transforms. The extracted chemically-meaningful reference spectra of Cu-species were analyzed by DFT-assisted XANES calculations. Cu-bisulfates werefound as the most energetically favorable poisoned Cu-species. The response of Cu-species to a reducing environment differs inthe fresh and SO2-poisoned catalysts. Differences in reducibility are related to the formation of quasi-linear Cu-complexes in the SO2-poisoned catalyst formed during heating in H2/He. Heating in H2/He leads to partial desulfurization of the poisoned catalyst. Cooling in H2/He after heating results in more facile formation of Cu-metal clusters in fresh catalyst than in SO2-poisoned.

  • 124.
    Bergman, Åke
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK), Avdelningen för miljökemi.
    Foreword2012Inngår i: Hormone-Disruptive Chemical Contaminants in Food / [ed] Ingemar Pongratz; Linda Bergander, London: Royal Society of Chemistry, 2012, s. v-viiKapittel i bok, del av antologi (Annet vitenskapelig)
  • 125.
    Bergner, Sandra
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi.
    Nilsson, Sandra
    Linköpings universitet, Institutionen för fysik, kemi och biologi.
    Screening of volatile compounds in washing water and cloths from the sponge cloth process2010Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Freudenberg Household Products AB in Norrköping are manufacturer of sponge cloths with the well-known brand names of Wettex® and Vileda®. The production is based on the viscose fiber process and involves a high chemical demand. Recent customer complaints involve a diffuse smell from the cloths that is like a “garage odor” and occurs after a few uses. The company’s theory is that the smell derives from a chemical used in the process called Exxal 9.

    The aim was to screen the washing water from two sections and the cloth before and after wash for the presence of Exxal 9 and other prominent components. The washing water samples consisted of a salt solution from one section and a water condensate from another section. A method to qualitatively and quantitatively examine the production samples was developed. To evaluate the variation over a short period of time, twelve samples were taken during four weeks. The focus for the analysis lay on production line Wx4, but comparisons with two other production lines, Wx7 and SL1, were also made. The method of choice was gas chromatography in combination with two different detectors; mass spectrometer for identification and flame ionization detector for quantification.

    Exxal 9 could be identified in both of the washing water sections but in very various concentrations. At the production line Wx4, the mean concentration in the mother lye was 61.96 µl/l whereas the mean concentration in the condensate was 0.24 µl/l. The comparison between the different production lines showed significant variations, where Wx4 had the highest concentration. In the cloths, Exxal 9 could only be found before it had been washed. The concentration in the cloths was not high enough for quantification. In both the washing waters and cloths, additional unknown peaks were found. Attempts to identify all the unknowns were made but only two compounds were included in the commercial library; 2-ethyl-1-hexanol and 2-(2-butoxyethoxy)-ethanol.

  • 126.
    Bergqvist, Cecilia
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för neurokemi.
    The role of nuclear membrane proteins in differentiation and chromatin organization2016Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The nuclear envelope, consisting of an outer and an inner nuclear membrane, surrounds the genomic material. The genomic material (chromatin) is highly structured with (transcriptionally inactive) heterochromatin mostly found in the nuclear periphery and (transcriptionally active) euchromatin mostly found in the nuclear interior. Underlying the nuclear envelope is the nuclear lamina that consists of lamin proteins and nuclear envelope transmembrane proteins (NETs), which organize chromatin in the nuclear periphery. There are several hundred uncharacterized tissue-specific NETs, with only a few linked to cellular differentiation. Induced pluripotent stem cells (iPSCs) enable studies of early differentiation and are a promising tool for cell replacement therapies.

    In this licentiate thesis, we have focused on investigating the role of the inner nuclear membrane protein Samp1 in chromatin organization and cell differentiation. Overexpression of Samp1 induced a fast differentiation of iPSCs, suggesting that Samp1 may be involved in the differentiation process. We have also developed a novel image analysis method to be able to monitor chromatin organization in live cells. Depletion of Samp1 affected chromatin distribution and resulted in increased formation of peripheral heterochromatin, contradictory to what is expected of other characterized NETs. It is possible that Samp1 might have a role in both differentiation and chromatin organization and that future studies might link these two processes together.

  • 127.
    Bergqvist, Cecilia
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för neurokemi.
    Figueroa, Ricardo
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för neurokemi.
    Markus, Robert
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för neurokemi.
    Beckman, Marie
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för neurokemi.
    Maxell, Danuta
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för neurokemi.
    Sousa, Paulo
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för neurokemi.
    Jafferali, Mohammed Hakim
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för neurokemi.
    Hallberg, Einar
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för neurokemi.
    Monitoring of the epigenetic state in live cellsManuskript (preprint) (Annet vitenskapelig)
  • 128.
    Bergqvist, Cecilia
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för neurokemi.
    Jafferali, Mohammed Hakim
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för neurokemi.
    Santosh, Gudise
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för neurokemi.
    Markus, Robert
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för neurokemi.
    Hallberg, Einar
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för neurokemi.
    An inner nuclear membrane protein induces rapid differentiation of human induced pluripotent stem cellsManuskript (preprint) (Annet vitenskapelig)
  • 129.
    Bergqvist, Jonas
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Österberg, Thomas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Melianas, Armantas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Ever Aguirre, Luis
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Tang, Zheng
    Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics, Technische Universität Dresden, Nöthnitzer Str. 61, Dresden, 01187, Germany.
    Cai, Wanzhu
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Ma, Zaifei
    Dresden Integrated Center for Applied Physics and Photonic Materials (IAPP) and Institute for Applied Physics, Technische Universität Dresden, Nöthnitzer Str. 61, Dresden, 01187, Germany.
    Kemerink, Martijn
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Komplexa material och system. Linköpings universitet, Tekniska fakulteten.
    Gedefaw, Desta
    Flinders Centre for Nanoscale Science and Technology, Flinders University, Sturt Road, Bedford Park, Adelaide, 5042, Australia.
    Andersson, Mats R.
    Flinders Centre for Nanoscale Science and Technology, Flinders University, Sturt Road, Bedford Park, Adelaide, Australia; Department of Chemistry and Chemical Engineering, Polymer Technology, Chalmers, University of Technology, Goteborg, Sweden.
    Inganäs, Olle
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biomolekylär och Organisk Elektronik. Linköpings universitet, Tekniska fakulteten.
    Asymmetric photocurrent extraction in semitransparent laminated flexible organic solar cells2018Inngår i: npj Flexible Electronics, ISSN 2397-4621, Vol. 2, nr 1, artikkel-id 4Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Scalable production methods and low-cost materials with low embodied energy are key to success for organic solar cells. PEDOT(PSS) electrodes meet these criteria and allow for low-cost and all solution-processed solar cells. However, such devices are prone to shunting. In this work we introduce a roll-to-roll lamination method to construct semitransparent solar cells with a PEDOT(PSS) anode and an polyethyleneimine (PEI) modified PEDOT(PSS) cathode. We use the polymer:PCBM active layer coated on the electrodes as the lamination adhesive. Our lamination method efficiently eliminates any shunting. Extended exposure to ambient degrades the laminated devices, which manifests in a significantly reduced photocurrent extraction when the device is illuminated through the anode, despite the fact that the PEDOT(PSS) electrodes are optically equivalent. We show that degradation-induced electron traps lead to increased trap-assisted recombination at the anode side of the device. By limiting the exposure time to ambient during production, degradation is significantly reduced. We show that lamination using the active layer as the adhesive can result in device performance equal to that of conventional sequential coating.

    Fulltekst (pdf)
    fulltext
  • 130.
    Bergström, L. Magnus
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Yt- och korrosionsvetenskap.
    Skoglund, Sara
    KTH, Skolan för kemivetenskap (CHE), Kemi, Yt- och korrosionsvetenskap.
    Edwards, Katarina
    Eriksson, Jonny
    Grillo, Isabelle
    Spontaneous Transformations between Surfactant Bilayers of Different Topologies Observed in Mixtures of Sodium Octyl Sulfate and Hexadecyltrimethylammonium Bromide2014Inngår i: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 30, nr 14, s. 3928-3938Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The influence of adding salt on the self-assembly in sodium octyl sulfate (SOS)-rich mixtures of the anionic surfactant SOS and the cationic surfactant hexadecyltrimethylammonium bromide (CTAB) have been investigated with the two complementary techniques, small-angle neutron scattering (SANS) and cryo-transmission electron microscopy. We are able to conclude that addition of a substantial amount of inert salt, NaBr, mainly has three effects on the structural behaviors: (i) the micelles become much larger at the transition from micelles to bilayers, (ii) the fraction of bilayer disks increases at the expense of vesicles, and (iii) bilayer aggregates perforated with holes are formed in the most diluted samples. A novel form factor valid for perforated bilayer vesicles and disks is introduced for the first time and, as a result, we are able to directly observe the presence of perforated bilayers by means of fitting SANS data with an appropriate model. Moreover, we are able to conclude that the morphology of bilayer aggregates changes according to the following sequence of different bilayer topologies, vesicles --> disks --> perforated bilayers, as the electrolyte concentration is increased and surfactant mole fraction in the bilayer aggregates approaches equimolarity. We are able to rationalize this sequence of transitions as a result of a monotonous increase of the bilayer saddle-splay constant ((k) over bar (bi)(c)) with decreasing influence from electrostatics, in agreement with theoretical predictions as deduced from the Poisson-Boltzmann theory.

  • 131.
    Berner, S.
    et al.
    Uppsala University, Uppsala, Sweden.
    Lidbaum, H.
    Uppsala University, Uppsala, Sweden.
    Ledung, G.
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Åhlund, J.
    Uppsala University, Uppsala, Sweden.
    Nilson, K.
    Uppsala University, Uppsala, Sweden.
    Schiessling, J.
    Uppsala University, Uppsala, Sweden.
    Gelius, U.
    Uppsala University, Uppsala, Sweden.
    Bäckvall, J.
    Stockholm University, Sweden.
    Puglia, C.
    Uppsala University, Uppsala, Sweden.
    Oscarsson, Sven
    Mälardalens högskola, Institutionen för biologi och kemiteknik.
    Electronic and structural studies of immobilized thiol-derivatized cobalt porphyrins on gold surfaces2007Inngår i: Applied Surface Science, ISSN 0169-4332, Vol. 253, nr 18, s. 7540-7548Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The immobilisation of thiol-derivatized cobalt porphyrins on gold surfaces has been studied in detail by means of combined scanning tunnelling microscopy (STM) and X-ray photoelectron spectroscopy (XPS). S-thioacetyl has been used as a protective group for the thiol. Different routes for deprotection of the acetyl groups were performed in acidic and in basic conditions. The results show the formation of monolayer films for the different preparation schemes. The immobilisation of the molecules on the gold surface takes place through the thiol-linkers by the formation of multiple thiolate bonds. In the case of layers formed with protected porphyrins approximately 60% of the linkers are bonded to the gold surface whereas for deprotected layers the amount of bonded linkers is increased up to about 80%. STM measurements revealed that the molecules arrange in a disordered overlayer and do not exhibit mobility on the gold surface. Annealing experiments have been performed in order to test the stability of the porphyrin layers. Disordered patterns have been observed in the STM images after annealing at T= 400 degrees C. XPS revealed that the sulphur content disappeared completely after annealing at T= 180 degrees C and that the molecules did undergo significant modifications.

  • 132.
    Besharat, Zahra
    et al.
    KTH Royal Institute of Technology, Sweden.
    Wakeham, Deborah
    KTH Royal Institute of Technology, Sweden.
    Johnson, C. Magnus
    KTH Royal Institute of Technology, Sweden.
    Luengo, Gustavo S.
    L’Oréal Research and Innovation, France.
    Greaves, Andrew
    L’Oréal Research and Innovation, France.
    Odnevall Wallinder, Inger
    KTH Royal Institute of Technology, Sweden.
    Göthelid, Mats
    KTH Royal Institute of Technology, Sweden.
    Rutland, Mark W.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Life Science. KTH Royal Institute of Technology, Sweden.
    Mixed monolayers of alkane thiols with polar terminal group on gold: Investigation of structure dependent surface properties2016Inngår i: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 484, s. 279-290Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Adsorption of thiols with cationic or anionic terminal group on gold has been studied from mixed solutions of 11-Amino-1-undecanethiol (AUT) and 3-Mercaptopropionic acid (MPA) using Quartz Crystal Microbalance with Dissipation (QCM-D), X-ray Photoelectron Spectroscopy (XPS), atomic force microscopy (AFM) and contact angles. The goal is to probe the nature of such layers, and the additivity or otherwise of the pH responsiveness, with a view to evaluate their suitability as smart materials. For each of the two pure (unmixed) cases, ordered molecular monolayers are formed with sulfur binding to gold and the alkane chain pointing out from the surface as expected. Adsorption from the thiol mixtures, however, leads to a more complex behaviour. The surface concentration of thiols from the mixtures, as determined by QCM-D, is considerably lower than for the pure cases and it reaches a minimum at a 3:1 MPA/AUT relative concentration in the solution. The XPS results confirm a reduction in adsorbed amount in mixtures with the lowest overall intensity for the 3:1 ratio. Monolayers formed from mixtures display a wettability which is much lower and less pH sensitive. Collectively these results confirm that for adsorption from mixed systems, the configuration is completely different. Complex formation in the mixed solutions leads to the adsorption of molecules parallel to the surface in an axially in-plane configuration. This parallel layer of thiols is mechanically relatively robust to nano-shaving based on AFM measurements. These results will have a significant impact on the design of biomimetic surface coatings particularly when mixtures of oppositely charged molecules are present on the surface, as is commonly the case in biological, proteinaceous surfaces (e.g. hair and skin).

  • 133. Beye, Martin
    et al.
    Oberg, Henrik
    Xin, Hongliang
    Dakovski, Georgi L.
    Dell'Angela, Martina
    Foehlisch, Alexander
    Gladh, Jorgen
    Hantschmann, Markus
    Hieke, Florian
    Kaya, Sarp
    Kuehn, Danilo
    LaRue, Jerry
    Mercurio, Giuseppe
    Minitti, Michael P.
    Mitra, Ankush
    Moeller, Stefan P.
    Ng, May Ling
    Nilsson, Anders
    Nordlund, Dennis
    Norskov, Jens
    Ostrom, Henrik
    Ogasawara, Hirohito
    Persson, Mats
    Schlotter, William F.
    Sellberg, Jonas A.
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Biomedicinsk fysik och röntgenfysik.
    Wolf, Martin
    Abild-Pedersen, Frank
    Pettersson, Lars G. M.
    Wurth, Wilfried
    Chemical Bond Activation Observed with an X-ray Laser2016Inngår i: Journal of Physical Chemistry Letters, ISSN 1948-7185, E-ISSN 1948-7185, Vol. 7, nr 18, s. 3647-3651Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The concept of bonding and antibonding orbitals is fundamental in chemistry. The population of those orbitals and the energetic difference between the two reflect the strength of the bonding interaction. Weakening the bond is expected to reduce this energetic splitting, but the transient character of bond-activation has so far prohibited direct experimental access. Here we apply time-resolved soft X-ray spectroscopy at a free electron laser to directly observe the decreased bonding antibonding splitting following bond-activation using an ultrashort optical laser pulse.

  • 134.
    Bhagavathiachari, Muthuraaman
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Elumalai, Viswanathan
    Vlachopoulos, Nick
    Safdari, Majid
    KTH, Skolan för kemivetenskap (CHE), Kemi, Tillämpad fysikalisk kemi. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Gao, Jiajia
    KTH, Skolan för kemivetenskap (CHE), Kemi. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Gardner, James M.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Tillämpad fysikalisk kemi. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Kloo, Lars
    KTH, Skolan för kemivetenskap (CHE), Kemi, Tillämpad fysikalisk kemi. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    A quasi-liquid polymer-based cobalt redox mediator electrolyte for dye-sensitized solar cells2013Inngår i: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 15, nr 40, s. 17419-17425Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Recently, cobalt redox electrolyte mediators have emerged as a promising alternative to the commonly used iodide/triiodide redox shuttle in dye-sensitized solar cells (DSCs). Here, we report the successful use of a new quasi-liquid, polymer-based electrolyte containing the Co3+/Co2+ redox mediator in 3-methoxy propionitrile solvent in order to overcome the limitations of high cell resistance, low diffusion coefficient and rapid recombination losses. The performance of the solar cells containing the polymer based electrolytes increased by a factor of 1.2 with respect to an analogous electrolyte without the polymer. The performances of the fabricated DSCs have been investigated in detail by photovoltaic, transient electron measurements, EIS, Raman and UV-vis spectroscopy. This approach offers an effective way to make high-performance and long-lasting DSCs.

  • 135.
    Bhattacharyya, Shubhankar
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Shah, Faiz Ullah
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Kemiteknik.
    Thermal stability of choline based amino acid ionic liquids2018Inngår i: Journal of Molecular Liquids, ISSN 0167-7322, E-ISSN 1873-3166, Vol. 266, s. 597-602Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Thermal stability of different choline based amino acid ionic liquids were studied. Both short term as well as long term thermal studies were carried out. Long term thermal studies of all ILs were carried out by isothermal TGA and short term thermal studies were measured by temperature ramped TGA. Isothermal TGA were studied at two different temperatures 100 °C and 150 °C for 500 min. Whereas, short term thermal stability represents as T2%, T5% and T10% which are the temperature at which 2%, 5% and 10% mass loss of ILs were observed. The effect of alkyl side chain on the cation, etherification of the cation as well structural variation of anion on the thermal stability of choline based ILs were investigated. It was observed that thermal characteristics of ILs towards temperature ramped TGA were different compared to isothermal TGA.

  • 136.
    Bibi, Sara Boscolo
    et al.
    Department of Physics, AlbaNova University Center, Stockholm University, 10691 Stockholm, Sweden.
    El-Zohry, Ahmed M.
    Department of Physics, AlbaNova University Center, Stockholm University, 10691 Stockholm, Sweden.
    Davies, Bernadette
    Department of Physics, AlbaNova University Center, Stockholm University, 10691 Stockholm, Sweden;Department of Materials and Environmental Chemistry, Stockholm University, Svante Arrhenius väg 16C, 114 18 Stockholm, Sweden.
    Grigorev, Vladimir
    Department of Physics, AlbaNova University Center, Stockholm University, 10691 Stockholm, Sweden.
    Goodwin, Christopher M.
    Department of Physics, AlbaNova University Center, Stockholm University, 10691 Stockholm, Sweden.
    Lömker, Patrick
    Department of Physics, AlbaNova University Center, Stockholm University, 10691 Stockholm, Sweden.
    Holm, Alexander
    Department of Physics, AlbaNova University Center, Stockholm University, 10691 Stockholm, Sweden.
    Ali-Löytty, Harri
    Surface Science Group, Photonics Laboratory, Tampere University, P.O. Box 692, FI-33014 Tampere University, Finland.
    Garcia-Martinez, Fernando
    Photon Science, Deutsches ElektronenSynchrotron (DESY), 22607 Hamburg, Germany.
    Schlueter, Christoph
    Photon Science, Deutsches ElektronenSynchrotron (DESY), 22607 Hamburg, Germany.
    Soldemo, Markus
    Department of Physics, AlbaNova University Center, Stockholm University, 10691 Stockholm, Sweden.
    Koroidov, Sergey
    Department of Physics, AlbaNova University Center, Stockholm University, 10691 Stockholm, Sweden.
    Hansson, Tony
    Department of Physics, AlbaNova University Center, Stockholm University, 10691 Stockholm, Sweden.
    Multi-spectroscopic study of electrochemically-formed oxide-derived gold electrodes2024Inngår i: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 26, nr 3, s. 2332-2340Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Oxide-derived metals are produced by reducing an oxide precursor. These materials, including gold, have shown improved catalytic performance over many native metals. The origin of this improvement for gold is not yet understood. In this study, operando non-resonant sum frequency generation (SFG) and ex situ high-pressure X-ray photoelectron spectroscopy (HP-XPS) have been employed to investigate electrochemically-formed oxide-derived gold (OD-Au) from polycrystalline gold surfaces. A range of different oxidizing conditions were used to form OD-Au in acidic aqueous medium (H3PO4, pH = 1). Our electrochemical data after OD-Au is generated suggest that the surface is metallic gold, however SFG signal variations indicate the presence of subsurface gold oxide remnants between the metallic gold surface layer and bulk gold. The HP-XPS results suggest that this subsurface gold oxide could be in the form of Au2O3 or Au(OH)3. Furthermore, the SFG measurements show that with reducing electrochemical treatments the original gold metallic state can be restored, meaning the subsurface gold oxide is released. This work demonstrates that remnants of gold oxide persist beneath the topmost gold layer when the OD-Au is created, potentially facilitating the understanding of the improved catalytic properties of OD-Au.

  • 137. Bickelhaupt, F Matthias
    et al.
    Nagle, Jeffrey K
    Klemm, William L
    Role of s-p orbital mixing in the bonding and properties of second-period diatomic molecules.2008Inngår i: Journal of Physical Chemistry A, ISSN 1089-5639, E-ISSN 1520-5215, Vol. 112, nr 11, s. 2437-46Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Qualitative molecular orbital theory is widely used as a conceptual tool to understand chemical bonding. Symmetry-allowed orbital mixing between atomic or fragment orbitals of different energies can greatly complicate such qualitative interpretations of chemical bonding. We use high-level Amsterdam Density Functional calculations to examine the issue of whether orbital mixing for some familiar second-row homonuclear and heteronuclear diatomic molecules results in net bonding or antibonding character for a given molecular orbital. Our results support the use of slopes of molecular orbital energy versus bond distance plots (designated radial orbital-energy slope: ROS) as the most useful criterion for making this determination. Calculated atomic charges and frontier orbital properties of these molecules allow their acid-base chemistry, including their reactivities as ligands in coordination chemistry, to be better understood within the context of the Klopman interpretation of hard and soft acid-base theory. Such an approach can be extended to any molecular species.

  • 138.
    Bidleman, Terry
    et al.
    Umeå University, Sweden.
    Kurt-Karakus, Perihan
    Bahcesehir University, Istanbul, Turkey.
    Armitage, James
    University of Toronto, Ontario, Canada.
    Brown, Tanya
    University of Victoria, British Columbia, Canada.
    Danon Schaffer, Monica
    University of British Columbia, Vancouver, Canada.
    Helm, Paul
    Ontario Ministry of the Environment, Toronto, Canada.
    Hung, Haley
    Meteorological Services Canada .
    Jantunen, Liisa
    Environment Canada.
    Kylin, Henrik
    Linköpings universitet, Institutionen för tema, Tema Miljöförändring. Linköpings universitet, Filosofiska fakulteten.
    Li, Yi-Fan
    Environment, Canada.
    Loock, Daniela
    Royal Military College of Canada.
    Luttmer, Carol
    Royal Military College of Canada.
    Ma, Jianmin
    Lanzhou University, Peoples Republic of China.
    Macdonald, Robie
    Fisheries and Oceans, Canada.
    Mackay, Don
    Trent University, Peterborough, Ontario, Canada.
    Reid, Liisa
    Trent University, Peterborough, Ontario, Canada.
    Reimer, Ken
    Royal Military College of Canada.
    Chapter 2: Properties, sources, global fate and transport2013Inngår i: Canadian Arctic Contaminants Assessment Report III 2013: Persistent Organic Pollutants in Canada’ s North / [ed] Derek Muir, Perihan Kurt-Karakus and Peter Stow, Ottawa: Northern Contaminants Program, Aboriginal Affairs and Northern Development Canada , 2013, s. 19-146Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    Part II of the second Canadian Arctic Contaminants Assessment Report (CACAR-II) began with a section on “Physicochemical Properties of Persistent Organic Pollutants”, which identified key physicochemical (pchem) properties, provided the rationale for their measurement or prediction and tabulated literature citations for chemicals that are of concern to the NCP (Bidleman et al. 2003). The section also discussed temperature dependence of pchem properties and their applications to describing partitioning in the physical environment.

    There is, and will continue to be, emphasis on predictive approaches to screening chemicals for persistence, bioaccumulation and toxic (PB&T)properties, as well as long-range atmospheric transport (LRAT) potential (Brown and Wania 2008, Czub et al. 2008, Fenner et al. 2005, Gouin andWania 2007, Howard and Muir 2010, Klasmeier et al. 2006, Matthies et al. 2009, Muir and Howard 2006). This has created the need for determining pchem properties of new and emerging chemicals of concern.

    Predicting gas exchange cycles of legacy persistent organic pollutants (POPs) and new and emerging chemicals of concern places a high demand on the accuracy of pchem properties, particularly the air/water partition coefficient, KAW. Hexachlorocyclohexanes (HCHs) in Arctic Ocean surface waters are close to air-water equilibrium, with excursions toward net volatilization or deposition that vary with location and season (Hargrave et al. 1993, Jantunen et al. 2008a, Lohmann et al. 2009, Su et al. 2006, Wong et al. 2011) while hexachlorobenzene (HCB) (Lohmann et al. 2009, Su et al. 2006, Wong et al. 2011) and some current use pesticides (CUPs) (Wong et al. 2011) are undergoing net deposition. The predicted Arctic Contamination Potential (ACP) for persistent organic chemicals is strongly influenced by ice cover due to its effect on air-water gas exchange (Meyer and Wania 2007).

    Many advances have taken place and numerous papers have been published since CACAR-II, which present new measurements and predictions of pchem properties. This section does not attempt to provide a comprehensive review of the field, or to compile pchem properties from the many studies. The approach taken is to highlight the reports which are most relevant to polar science, particularly in areas of improving reliability of pchem properties for POPs, improving experimental techniques and comparing predictive methods. The section ends with a discussion of polyparameter linear free energy relationships (pp-LFERs), which goes beyond partitioning descriptions based on single pchem properties by taking into account specific chemical interactions that can take place in airsurface and water-surface exchange processes. A detailed list of chemical names and nomenclature are provided in the Glossary.

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  • 139.
    Biler, Michal
    et al.
    Department of Biophysics, Centre of the Region Haná for Biotechnological and Agricultural Research, Palacký University, Šlechtitelů 27, Olomouc, Czech Republic; INSERM UMR-S850, Univ. Limoges, School of Pharmacy, University de Limoges, 2 rue du Dr Marcland, 87 025 Limoges, France.
    Biedermann, David
    Valentova, Katerina
    Kren, Vladimir
    Kubala, Martin
    Quercetin and its analogues: optical and acido-basic properties2017Inngår i: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 19, nr 39, s. 26870-26879Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This study is focused on eight structurally analogous natural flavonoids that exhibit a wide range of biological activities, which are of interest in pharmacy, cosmetics and the food industry. Using both experimental and theoretical approaches, we relate their fundamental physico-chemical properties to the structural motifs, with particular focus on UV/Vis absorption properties and pH dependence. We highlight the role of the C2-C3 double bond, whose presence or absence is responsible for the switch between absorption bands in the UVB and UVA regions, which is rationalized by strong modification of the involved molecular orbitals. After deprotonation in an alkaline environment, a typical switch in intensity at the maximum absorption wavelength (lambda(max)) is observed enabling the calculation of pK(a) values for compounds with a C2-C3 single bond, whereas a bathochromic shift of lambda(max) vs. pH is observed for the C2-C3 double bond containing compounds. These behaviors are also rationalized and understood by MO analysis. Interestingly, high pH (above 11 for ampelopsin and above 9 for myricetin) induces the formation of a long-wavelength peak arising from double and/or triple deprotonation. Substitution at position C3 by the OH group has almost no effect on lambda(max) for taxifolin and eriodictyol, whereas the effect is larger for quercetin and luteolin. An additional sugar moiety at C3 has a stabilizing effect and induces only minor changes in spectral behavior.

  • 140. Bjarnsholt, T.
    et al.
    Buhlin, K.
    Dufrêne, Y. F.
    Gomelsky, M.
    Moroni, A.
    Ramstedt, Madeleine
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Rumbaugh, K. P.
    Schulte, T.
    Sun, L.
    Åkerlund, B.
    Römling, U.
    Biofilm formation – what we can learn from recent developments2018Inngår i: Journal of Internal Medicine, ISSN 0954-6820, E-ISSN 1365-2796, Vol. 284, nr 4, s. 332-345Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Although biofilms have been observed early in the history of microbial research, their impact has only recently been fully recognized. Biofilm infections, which contribute to up to 80% of human microbial infections, are associated with common human disorders, such as diabetes mellitus and poor dental hygiene, but also with medical implants. The associated chronic infections such as wound infections, dental caries and periodontitis significantly enhance morbidity, affect quality of life and can aid development of follow-up diseases such as cancer. Biofilm infections remain challenging to treat and antibiotic monotherapy is often insufficient, although some rediscovered traditional compounds have shown surprising efficiency. Innovative anti-biofilm strategies include application of anti-biofilm small molecules, intrinsic or external stimulation of production of reactive molecules, utilization of materials with antimicrobial properties and dispersion of biofilms by digestion of the extracellular matrix, also in combination with physical biofilm breakdown. Although basic principles of biofilm formation have been deciphered, the molecular understanding of the formation and structural organization of various types of biofilms has just begun to emerge. Basic studies of biofilm physiology have also resulted in an unexpected discovery of cyclic dinucleotide second messengers that are involved in interkingdom crosstalk via specific mammalian receptors. These findings even open up new venues for exploring novel anti-biofilm strategies.

  • 141.
    Bjurlid, Filip
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Polybrominated dibenzo-p-dioxins and furans: from source of emission to human exposure2018Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Brominated flame retardants (BFRs), which are ubiquitous in modern life and the environment, are the major source for polybrominated dibenzo-p-dioxins and furans (PBDD/Fs). The knowledge about PBDD/Fs is lim-ited compared to other environmental pollutants, even though PBDD/Fs show similar toxicity as polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) which are considered to be among the most toxic man-made substances. The aim of the thesis was to provide a better understanding of PBDD/Fs by investigating the occurrence and distribution of PBDD/Fs in the following matrices: soot and gas from an accidental fire site which is a typical source of emission, blubber from marine mammals living in both far remote areas as well as areas close to anthropogenic sources, and finally in human milk from ten nursing mothers.

    PBDD/Fs was detected in blubber from pilot whales sampled around Faroe Islands, which proved the occurrence in marine mammals in a far remote area. The findings of PBDD/Fs in blubber from Baltic ringed seals showed slightly higher concentrations compared to the pilot whales, which is expected since the Baltic Sea in among the world’s most contam-inated water areas. In the pilot whales and the ringed seals, the average contribution from PBDD/Fs to the total (PCDD/F+PBDD/F) Total Equiv-alent Quantity (TEQ) was low, (1-8%). In gas and soot samples from the accidental fire site, PBDD/Fs were detected in all samples and the contri-bution of PBDD/Fs to the total TEQ was close to 100%. In the human milk samples, PBDD/Fs were detected in all samples and the average con-tribution of PBDD/Fs to the total TEQ was 40%. The results indicate that PBDD/Fs are of concern for human exposure, and should be monitored together with PCDD/Fs in future studies. Moreover, the occurrence at ac-cidental fire sites indicate that PBDD/Fs are a source for occupational ex-posure for firefighters and other professionals. The impact from PBDD/Fs on marine mammalians seems to be of less concern.

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  • 142.
    Bjurlid, Filip
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Dam, Maria
    Faroe Islands' Environment Agency, Argir, Denmark.
    Hoydal, Katrin
    Faroe Islands' Environment Agency, Argir, Denmark.
    Hagberg, Jessika
    Örebro universitet, Institutionen för naturvetenskap och teknik. Department of Occupational and Environmental Medicine, Faculty of Health and Medical Sciences, Örebro University, Örebro, Sweden.
    Occurrence of polybrominated dibenzo-p-dioxins, dibenzofurans (PBDD/Fs) and polybrominated diphenyl ethers (PBDEs) in pilot whales (Globicephala melas) caught around the Faroe Islands2018Inngår i: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 195, s. 11-20Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Blubber from Faroese pilot whales (Globicephala melas) was analysed for brominated dioxins PBDD/Fs, with a subset also analysed for chlorinated dioxins, PCDD/Fs. The studied individuals were restricted to juvenile male whales sampled in the Faroe Islands during the period 1997–2013. Among the PBDD/Fs, the furans were predominant, although the relative abundance of various congeners differed between samples. Furans accounted for, on average, 79% of the ∑PBDD/Fs in the samples, with 1,2,3,4,6,7,8-HpBDF the most abundant congener, found in half of the analysed pilot whales. The concentration range for ∑PBDD/Fs among the samples was 0.080–71 pg/g l.w. (lipid weight), and the sum of toxic equivalents ranged from 0.0039 to 4.7 pg TEQ/g l.w. No relationship was found between PBDD/Fs and PCDD/Fs. In addition, 20 pilot whale samples from the period 2010–2013 were analysed for PBDEs. Several PBDE congeners were found in all of the sampled pilot whales, and at noticeably higher levels than PBDD/Fs and PCDD/Fs. The ∑PBDEs ranged from 140 to 1900 ng/g l.w., with BDE #47 the most abundant congener detected in the samples. Results from the present study were then compared with data from previous studies on pilot wales to investigate temporal trends between 1986 and 2013. The comparison indicated that PBDE concentrations in juvenile males have decreased from 1996 to the latest observations in 2013. No relationship between the concentration levels of PBDD/Fs and PBDEs in the sampled pilot whales could be identified, which indicates possible differences in the metabolism of, or exposure to, PBDEs and PBDD/Fs.

  • 143.
    Bjurlid, Filip
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Hagberg, Jessika
    Örebro universitet, Institutionen för naturvetenskap och teknik. Department of Occupational and Environmental Medicine, Faculty of Medicine and Health, Örebro University, Örebro, Sweden.
    Polybrominated dibenzo-p-dioxins and dibenzofurans and Stockholm Convention POPs in human milk: evaluation of the effects of breastfeeding durationManuskript (preprint) (Annet vitenskapelig)
  • 144.
    Bjurlid, Filip
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Roos, Anna
    Department of Environmental Research and Monitoring, Swedish Museum of Natural History, Stockholm, Sweden.
    Ericson Jogsten, Ingrid
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Hagberg, Jessika
    Örebro universitet, Institutionen för naturvetenskap och teknik. Department of Occupational and Environmental Medicine, Faculty of Health and Medical Sciences, Örebro University, Örebro, Sweden.
    Temporal trends of PBDD/Fs, PCDD/Fs, PBDEs and PCBs in ringed seals from the Baltic Sea (Pusa hispida botnica) between 1974 and 20152018Inngår i: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 616-617, s. 1374-1383Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Temporal trends in exposure to persistent organic pollutants (POPs) were assessed in 22 pooled samples gathered from 69 individuals of Baltic ringed seal (Pusa hispida botnica) from 1974 to 2015. Samples were analysed for polybrominated dibenzo-p-dioxins and furans (PBDD/Fs), polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs), polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs). No previous study has reported on the occurrence of PBDD/Fs in marine mammals in the Baltic Sea. Concentrations of pollutants in Baltic ringed seal, a marine mammal and top predator, can be used as an indicator of pollutants concentrations in the Baltic region.

    Visual inspection of data did not show any temporal trends for PBDD/Fs, while the PCDD/Fs and PCBs showed decreasing concentrations between 1974 and 2015. PBDEs increased until the end of the 1990s and then decreased until the end of the period. ∑ PBDD/Fs ranged from 0.5–52.3 pg/g lipid weight (l.w.) (0.08–4.8 pg TEQ/g l.w.), with 1,2,3,4,6,7,8-HpBDF contributing on average 61% to ∑ PBDD/Fs. ∑ PCDD/Fs ranged from 103 to 1480 pg/g l.w. (39–784 pg TEQ/g l.w.), with 1,2,3,6,7,8-HxCDD, 1,2,3,7,8-PeCDD and 2,3,4,7,8-PeCDF showing the highest average concentrations. PBDD/F toxic equivalents (TEQ) contributed on average 1.1% to the total (PBDD/F + PCDD/F) TEQ. The ∑ PBDEs concentration range was 18.7–503 ng/g l.w., with BDE #47 the predominant congener. The concentration range for ∑ PCBs was 2.8–40.1 μg/g l.w., with #138 and #153 the most abundant congeners. Visual inspection of the data showed decreasing concentrations for all compound groups except PBDD/Fs. A slight increase in the PBDD/Fs concentrations was observed from 2004 onwards. This observation needs to be investigated further.

  • 145.
    Björk, Jonas
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Materialdesign. Linköpings universitet, Tekniska fakulteten.
    Rosén, Johanna
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Materialdesign. Linköpings universitet, Tekniska fakulteten.
    Functionalizing MXenes by Tailoring Surface Terminations in Different Chemical Environments2021Inngår i: Chemistry of Materials, ISSN 0897-4756, E-ISSN 1520-5002, Vol. 33, nr 23, s. 9108-9118Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Two-dimensional metal carbides and nitrides-MXenes-represent a group of materials which have attained growing attention over the last decade due to their chemical versatility, making them highly promising in areas such as energy storage, superconductivity, and heterogenous catalysis. Surface terminations are a natural consequence of the MXene synthesis, conventionally consisting of O, OH, and F. However, recent studies have extended the chemical domain of the surface terminations to other elements, and they should be considered as an additional parameter governing the MXene properties. There is a shortfall in the understanding of how various chemical species could act as terminations on different MXenes. In particular, there is limited comprehension in which chemical environments different terminations are stable. Here, we present an extensive theoretical study of the surface terminations of MXenes in different atmospheres by considering in total six experimentally achieved MXenes (Ti2C, Nb2C, V2C, Mo2C, Ti3C2, and Nb4C3) and twelve surface terminations (O, OH, N, NH, NH2, S, SH, H, F, Cl, Br, and I). We consider fully terminated (single termination) MXenes and also the impact of substituting individual terminations. Our study provides insights into what terminations are stable on which MXenes in different chemical environments, with predictions of how to obtain single-termination MXenes and which MXenes are resilient under ambient conditions. In addition, we propose synthesis protocols of MXenes which have not yet been realized in experiments. It is anticipated that alongside the development of new synthesis routes, our study will provide design rules for how to tailor the surface terminations of MXenes.

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  • 146.
    Björkbacka, Åsa
    KTH, Skolan för kemivetenskap (CHE).
    Radiation induced corrosion of copper2011Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    The Swedish concept for storage of highly radioactive spent nuclear fuel is called the KBS-3 program. The proposed procedure is that the waste will be stored in a deep repository, 500 meters down in the Swedish bedrock, for 100 000 years. The fuel will be sealed inside cast iron cylinders surrounded by copper. The iron-copper canisters will then be placed one by one in holes and embedded in bentonite clay. The environment in the deep repository will be that of an underground rock cave, there will be groundwater and low amounts of oxygen present.

    Substances which are likely to react with the copper canister and cause corrosion are oxygen, sulphides and reactive water radiolysis products. Gamma radiation from the spent nuclear fuel will penetrate through the canister and further into the bentonite clay. When the gamma radiation comes in contact with the water in the bentonite clay, water radiolysis will occur. Corrosive radiolysis products are for example hydroxyl radicals, solvated electrons and hydrogen peroxide.

    The main purpose of this work was to study the effect of gamma radiation on copper pieces, in an aqueous environment, both under oxic and anoxic conditions. The surfaces of the copper pieces were characterized using scanning electron microscopy (SEM) and infrared absorption spectroscopy (IRAS). The dissolution of copper was measured using inductively coupled plasma spectroscopy (ICP).

    A second study was also performed where the reactions of three different oxidants; hydrogen peroxide, permanganate and iridium hexachloride, were studied in the presence of copper in an inert environment. All of the reactions were studied spectrophotometrically and the dissolution of copper was measured using inductively coupled plasma spectroscopy (ICP).

    The SEM measurements showed corrosion products on the irradiated copper pieces both under oxic and anoxic conditions. Under anoxic conditions the corrosion products had a center of a small cavity which was surrounded by a larger, flat, circular area. From that area, wider cavities were spreading out in apparently random directions. SEM-EDS measurements detected oxygen on the surface of the corrosion products. ICP measurements of the water phase showed that the water from irradiated samples contained higher levels of copper than unirradiated samples. ICP measurements from the reactions of copper in the presence of oxidants showed that copper was only dissolved in the presence of iridium hexachloride.

    These results show that gamma radiation causes corrosion of copper in an aqueous environment, both under oxic and anoxic conditions. It can also be concluded that hydrogen peroxide is not the radiolysis product that causes the dissolution of copper when copper is irradiated in an aqueous and inert environment.

    Fulltekst (pdf)
    FULLTEXT01
  • 147.
    Björklund, Sam
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska fakulteten.
    Characterization of Inosine triphosphate pyrophosphatase, an important protein involved in purine metabolism2015Independent thesis Basic level (degree of Bachelor), 10,5 poäng / 16 hpOppgave
    Abstract [en]

    The enzyme inosine triphosphate pyrophosphatase (ITPase) is responsible for controlling the levels of the by-products guanosine monophosphate (GMP) and adenosine monophosphate (AMP) through their precursor inosine monophosphate (IMP). ). Human ITPase consists of a 194-amino acid homodimer which relies upon either an Mg2+ ion or a Mn2+ ion for catalytic activity, and orthologs of this protein have been found in many different organisms.

    The purpose of this project was to try out methods learned throughout the education and to use this knowledge to gather new data about the human protein inosine triphosphate pyrophosphatase (ITPase). The protein was expressed in BL21/DE3 cells from a pre-made vector. Experiments performed during this project include secondary- and tertiary stability measurements, tryptophan fluorescence spectra, binding curve and thermic stability to ITPase with ANS and methotrexate.

    The Tm-value of human ITPase was examined with Trp-Fluorescence, ANS-fluorescence and Near-UV and Far-UV circular dichroism (CD). The stability of ITPase monitored by Near-UV as well as Far-UV coincides, indicating that secondary- and tertiary-unfolding occur simultaneously without any intermediates.

    The results of Trp-fluorescence showed that the tryptophans were already exposed and thus it did not yield a reliable result. The binding properties of ANS and MTX to ITPase were also examined.

    Fulltekst (pdf)
    fulltext
  • 148. Björlenius, Berndt
    et al.
    Ripszám, Mátyás
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Haglund, Peter
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Lindberg, Richard H.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Tysklind, Mats
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Fick, Jerker
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Pharmaceutical residues are widespread in Baltic Sea coastal and offshore waters: Screening for pharmaceuticals and modelling of environmental concentrations of carbamazepine2018Inngår i: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 633, s. 1496-1509Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The consumption of pharmaceuticals worldwide coupled with modest removal efficiencies of sewage treatment plants have resulted in the presence of pharmaceuticals in aquatic systems globally. In this study, we investigated the environmental concentrations of a selection of 93 pharmaceuticals in 43 locations in the Baltic Sea and Skagerrak. The Baltic Sea is vulnerable to anthropogenic activities due to a long turnover time and a sensitive ecosystem in the brackish water. Thirty-nine of 93 pharmaceuticals were detected in at least one sample, with concentrations ranging between 0.01 and 80 ng/L. One of the pharmaceuticals investigated, the anti-epileptic drug carbamazepine, was widespread in coastal and offshore seawaters (present in 37 of 43 samples). In order to predict concentrations of pharmaceuticals in the sub-basins of the Baltic Sea, a mass balance-based grey box model was set up and the persistent, widely used carbamazepine was selected as the model substance. The model was based on hydrological and meteorological sub-basin characteristics, removal data from smaller watersheds and wastewater treatment plants, and statistics relating to population, consumption and excretion rate of carbamazepine in humans. The grey box model predicted average environmental concentrations of carbamazepine in sub-basins with no significant difference from the measured concentrations, amounting to 0.57–3.2 ng/L depending on sub-basin location. In the Baltic Sea, the removal rate of carbamazepine in seawater was estimated to be 6.2 10−9 s−1 based on a calculated half-life time of 3.5 years at 10 °C, which demonstrates the long response time of the environment to measures phasing out persistent or slowly degradable substances such as carbamazepine. Sampling, analysis and grey box modelling were all valuable in describing the presence and removal of carbamazepine in the Baltic Sea.

    Fulltekst (pdf)
    fulltext
  • 149.
    Björneholm, Olle
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Molekyl- och kondenserade materiens fysik.
    Hansen, Martin H.
    Tech Univ Denmark, DK-2800 Lyngby, Denmark.;Univ Copenhagen, Dept Chem, Univ Pk 5, DK-2100 Copenhagen, Denmark..
    Hodgson, Andrew
    Univ Liverpool, Dept Chem, Liverpool L69 7ZD, Merseyside, England..
    Liu, Li-Min
    UCL, London Ctr Nanotechnol, Thomas Young Ctr, Dept Phys & Astron, London WC1E 6BT, England.;UCL, Dept Chem, London WC1E 6BT, England.;Beijing Computat Sci Res Ctr, Beijing 100193, Peoples R China..
    Limmer, David T.
    Princeton Univ, Princeton Ctr Theoret Sci, Princeton, NJ 08544 USA..
    Michaelides, Angelos
    UCL, London Ctr Nanotechnol, Thomas Young Ctr, Dept Phys & Astron, London WC1E 6BT, England.;UCL, Dept Chem, London WC1E 6BT, England..
    Pedevilla, Philipp
    UCL, London Ctr Nanotechnol, Thomas Young Ctr, Dept Phys & Astron, London WC1E 6BT, England.;UCL, Dept Chem, London WC1E 6BT, England..
    Rossmeisl, Jan
    Univ Copenhagen, Dept Chem, Univ Pk 5, DK-2100 Copenhagen, Denmark..
    Shen, Huaze
    Peking Univ, Int Ctr Quantum Mat, Beijing 100871, Peoples R China.;Peking Univ, Sch Phys, Beijing 100871, Peoples R China..
    Tocci, Gabriele
    UCL, London Ctr Nanotechnol, Thomas Young Ctr, Dept Phys & Astron, London WC1E 6BT, England.;UCL, Dept Chem, London WC1E 6BT, England.;Ecole Polytech Fed Lausanne, Sch Engn, Inst Bioengn & Mat Sci & Engn, Lab Fundamental BioPhoton,Lab Computat Sci & Mode, CH-1015 Lausanne, Switzerland.;Ecole Polytech Fed Lausanne, Lausanne Ctr Ultrafast Sci, CH-1015 Lausanne, Switzerland..
    Tyrode, Eric
    KTH Royal Inst Technol, Dept Chem, S-10044 Stockholm, Sweden..
    Walz, Marie-Madeleine
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Molekyl- och kondenserade materiens fysik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Beräkningsbiologi och bioinformatik.
    Werner, Josephina
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Molekyl- och kondenserade materiens fysik. Swedish Univ Agr Sci, Dept Chem & Biotechnol, Box 7015, S-75007 Uppsala, Sweden..
    Bluhm, Hendrik
    Lawrence Berkeley Natl Lab, Div Chem Sci, Berkeley, CA 94720 USA..
    Water at Interfaces2016Inngår i: Chemical Reviews, ISSN 0009-2665, E-ISSN 1520-6890, Vol. 116, nr 13, s. 7698-7726Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    The interfaces of neat water and aqueous solutions play a prominent role in many technological processes and in the environment. Examples of aqueous interfaces are ultrathin water films that cover most hydrophilic surfaces under ambient relative humidities, the liquid/solid interface which drives many electrochemical reactions, and the liquid/vapor interface, which governs the uptake and release of trace gases by the oceans and cloud droplets. In this article we review some of the recent experimental and theoretical advances in our knowledge of the properties of aqueous interfaces and discuss open questions and gaps in our understanding.

  • 150.
    Björnsdotter, Maria
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Ultra-short-chain perfluoroalkyl acids: Environmental occurrence, sources and distribution2021Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Ultra-short-chain perfluoroalkyl acids (PFAAs) is a group of highly fluorinated and very stable chemicals. Their small molecular structure in combination with the acidic functional group result in highly polar compounds and concern has been raised as these substances may threaten our drinking water supplies.

    The aim with this thesis was to study and assess the occurrence, sources, and distribution of ultra-short-chain PFAAs in the environment. The main objectives were to analyze ultra-short-chain PFAAs in surface water with different anthropogenic impact, in atmospheric deposition and surface snow at local and remote locations, and to examine the relevance of local and diffuse input pathways to Lake Vättern, Sweden.

    The results revealed that ultra-short-chain PFAAs are released to the environment from various sources such as firefighting training sites, landfills, and hazardous waste management facilities. Trifluoroacetic acid (TFA) and perfluoropropanoic acid (PFPrA) were detected in all atmospheric deposition samples and surface snow samples, including those collected at remote sites in the Arctic. Atmospheric oxidation of volatile precursors was found to play a major role in the global distribution of these as well as being the main input pathway to Lake Vättern. A total annual flux of 120–170 kg and 1.3–2.0 kg was observed for TFA and PFPrA, respectively.

    Trifluoromethane sulfonic acid (TFMS) was detected in most samples and was reported for the first time in atmospheric deposition and surface snow at local as well as remote locations. The discovery of TFMS at remote locations suggests that TFMS is globally distributed. Neither atmospheric degradation of volatile precursors, nor the long-range oceanic transport seem to be main sources of TFMS to the Arctic environment, and local sources seem to be of higher importance for TFMS input to Lake Vättern.

    Fulltekst (pdf)
    Ultra-short-chain perfluoroalkyl acids: Environmental occurrence, sources and distribution
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