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  • 1.
    Adeboye, Peter Temitope
    et al.
    Chalmers University of Technology, Sweden.
    Bettiga, Maurizio
    Chalmers University of Technology, Sweden.
    Aldaeus, Fredrik
    RISE, Innventia.
    Larsson, Per Tomas
    RISE, Innventia.
    Olsson, Lars
    RISE, Innventia. Chalmers University of Technology, Sweden.
    Catabolism of coniferyl aldehyde, ferulic acid and p-coumaric acid by Saccharomyces cerevisiae yields less toxic products2015In: Microbial Cell Factories, ISSN 1475-2859, E-ISSN 1475-2859, Vol. 14, no 1, article id 149Article in journal (Refereed)
    Abstract [en]

    Background: Lignocellulosic substrates and pulping process streams are of increasing relevance to biorefineries for second generation biofuels and biochemical production. They are known to be rich in sugars and inhibitors such as phenolic compounds, organic acids and furaldehydes. Phenolic compounds are a group of aromatic compounds known to be inhibitory to fermentative organisms. It is known that inhibition of Sacchromyces cerevisiae varies among phenolic compounds and the yeast is capable of in situ catabolic conversion and metabolism of some phenolic compounds. In an approach to engineer a S. cerevisiae strain with higher tolerance to phenolic inhibitors, we selectively investigated the metabolic conversion and physiological effects of coniferyl aldehyde, ferulic acid, and p-coumaric acid in Saccharomyces cerevisiae. Aerobic batch cultivations were separately performed with each of the three phenolic compounds. Conversion of each of the phenolic compounds was observed on time-based qualitative analysis of the culture broth to monitor various intermediate and final metabolites. Result: Coniferyl aldehyde was rapidly converted within the first 24 h, while ferulic acid and p-coumaric acid were more slowly converted over a period of 72 h. The conversion of the three phenolic compounds was observed to involved several transient intermediates that were concurrently formed and converted to other phenolic products. Although there were several conversion products formed from coniferyl aldehyde, ferulic acid and p-coumaric acid, the conversion products profile from the three compounds were similar. On the physiology of Saccharomyces cerevisiae, the maximum specific growth rates of the yeast was not affected in the presence of coniferyl aldehyde or ferulic acid, but it was significantly reduced in the presence of p-coumaric acid. The biomass yields on glucose were reduced to 73 and 54 % of the control in the presence of coniferyl aldehyde and ferulic acid, respectively, biomass yield increased to 127 % of the control in the presence of p-coumaric acid. Coniferyl aldehyde, ferulic acid and p-coumaric acid and their conversion products were screened for inhibition, the conversion products were less inhibitory than coniferyl aldehyde, ferulic acid and p-coumaric acid, indicating that the conversion of the three compounds by Saccharomyces cerevisiae was also a detoxification process. Conclusion: We conclude that the conversion of coniferyl aldehyde, ferulic acid and p-coumaric acid into less inhibitory compounds is a form of stress response and a detoxification process. We hypothesize that all phenolic compounds are converted by Saccharomyces cerevisiae using the same metabolic process. We suggest that the enhancement of the ability of S. cerevisiae to convert toxic phenolic compounds into less inhibitory compounds is a potent route to developing a S. cerevisiae with superior tolerance to phenolic compounds.

  • 2.
    Alriksson, Björn
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Processum.
    Eskilsson, Martin
    Holmen, Sweden.
    Johansson, Emma
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Processum.
    Lapidot, Shaul
    Melodea, Israel.
    Norström, Markus
    RISE, SP – Sveriges Tekniska Forskningsinstitut.
    Schultz-Eklund, Ola
    Holmen, Sweden .
    Shkedi, Yoram
    Melodea, Israel.
    Svedberg, Anna
    MoRe Research, Sweden.
    Svensson, Stefan
    MoRe Research, Sweden.
    Swerin, Agne
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Material och ytteknik.
    Europe’s first pilot facility for cellulose nanocrystals (CNC)2016In: Annual Surface and Materials Chemistry Symposium and Materials for tomorrow (ASMCS 2016), 2016Conference paper (Refereed)
  • 3.
    An, Junxue
    et al.
    KTH Royal Institute of Technology, Sweden.
    Liu, Xiaoyan
    KTH Royal Institute of Technology, Sweden.
    Dedinaite, Andra
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials. KTH Royal Institute of Technology, Sweden.
    Korchagina, Evgeniya
    University of Montreal, Canada.
    Winnik, Francoise M.
    University of Montreal, Canada; National Institute for Materials Science, Japan; University of Helsinki, Finland.
    Claesson, Per M.
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials. KTH Royal Institute of Technology, Sweden.
    Dedinaite, Andra
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials. KTH Royal Institute of Technology, Sweden.
    Effect of solvent quality and chain density on normal and frictional forces between electrostatically anchored thermoresponsive diblock copolymer layers2017In: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 487, p. 88-96Article in journal (Refereed)
    Abstract [en]

    Equilibration in adsorbing polymer systems can be very slow, leading to different physical properties at a given condition depending on the pathway that was used to reach this state. Here we explore this phenomenon using a diblock copolymer consisting of a cationic anchor block and a thermoresponsive block of poly(2-isopropyl-2-oxazoline), PIPOZ. We find that at a given temperature different polymer chain densities at the silica surface are achieved depending on the previous temperature history. We explore how this affects surface and friction forces between such layers using the atomic force microscope colloidal probe technique. The surface forces are purely repulsive at temperatures <40 °C. A local force minimum at short separation develops at 40 °C and a strong attraction due to capillary condensation of a polymer-rich phase is observed close to the bulk phase separation temperature. The friction forces decrease in the cooling stage due to rehydration of the PIPOZ chain. A consequence of the adsorption hysteresis is that the friction forces measured at 25 °C are significantly lower after exposure to a temperature of 40 °C than prior to heating, which is due to higher polymer chain density on the surface after heating.

  • 4.
    Ankerfors, M.
    et al.
    RISE, Innventia.
    Duker, E.
    Lindström, T.
    RISE, Innventia.
    Topo-chemical modification of fibres by grafting of carboxymethyl cellulose in pilot scale2013In: Nordic Pulp and Paper Research Journal, ISSN 0283-2631 , no 1, p. 6-14Article in journal (Refereed)
  • 5.
    Appelquist, Karin
    et al.
    RISE - Research Institutes of Sweden, Built Environment, CBI Swedish Cement and Concrete Research Institute.
    Mueller, Urs
    RISE - Research Institutes of Sweden, Built Environment, CBI Swedish Cement and Concrete Research Institute.
    Trägårdh, Jan
    RISE - Research Institutes of Sweden, Built Environment, CBI Swedish Cement and Concrete Research Institute.
    Detection of potential alkali-silica reactivity of aggregates from Sweden2017Conference paper (Other academic)
  • 6.
    Arrhenius, Karine
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Kemi.
    Brown, Andrew S.
    NPL National Physical Laboratory, UK.
    van der Veen, Adriaan M. H.
    VSL Dutch Metrology Institute, Netherlands.
    Suitability of different containers for the sampling and storage of biogas and biomethane for the determination of the trace-level impurities - A review2016In: Analytica Chimica Acta, ISSN 0003-2670, E-ISSN 1873-4324, Vol. 902, p. 22-32Article, review/survey (Refereed)
    Abstract [en]

    The traceable and accurate measurement of biogas impurities is essential in order to robustly assess compliance with the specifications for biomethane being developed by CEN/TC408. An essential part of any procedure aiming to determinate the content of impurities is the sampling and the transfer of the sample to the laboratory. Key issues are the suitability of the sample container and minimising the losses of impurities during the sampling and analysis process. In this paper, we review the state-of-the-art in biogas sampling with the focus on trace impurities. Most of the vessel suitability studies reviewed focused on raw biogas. Many parameters need to be studied when assessing the suitability of vessels for sampling and storage, among them, permeation through the walls, leaks through the valves or physical leaks, sorption losses and adsorption effects to the vessel walls, chemical reactions and the expected initial concentration level. The majority of these studies looked at siloxanes, for which sampling bags, canisters, impingers and sorbents have been reported to be fit-for-purpose in most cases, albeit with some limitations. We conclude that the optimum method requires a combination of different vessels to cover the wide range of impurities commonly found in biogas, which have a wide range of boiling points, polarities, water solubilities, and reactivities. The effects from all the parts of the sampling line must be considered and precautions must be undertaken to minimize these effects. More practical suitability tests, preferably using traceable reference gas mixtures, are needed to understand the influence of the containers and the sampling line on sample properties and to reduce the uncertainty of the measurement.

  • 7.
    Athley, Karin
    et al.
    RISE, Innventia.
    Granlöf, Lars
    RISE, Innventia.
    Söderberg, Daniel
    RISE, Innventia.
    Ström, Göran
    RISE, Innventia.
    Optimizing the benefit of retention chemicals2014Conference paper (Refereed)
    Abstract [en]

    Pre-flocculation of filler has been tested as a concept for improving the retention of filler and the strength properties of the sheet. The impact of the size of the filler floes on the mechanical retentionin a fibre network was investigated using a modified laboratory hand sheet former. The mechanical retention was found to increase linearly with both particle size and grammage of the fibre web. These results were confirmed in a full scale production trial on the FEX pilot paper machine at Innventia. Here different filler floe sizes were created through different chemical pre-flocculation strategies. The particle size in the flow to the headbox was measured with FBRM, and a linear relation between particle size and filler retention was found. Corresponding linear relation was seen in a pilot trial when adding filler and retention aid conventionally. This implies that mechanical retention constitute an important part of the filler retention not only upon pre-flocculation but also with conventional addition of filler and retention aid. Thus, the particle size before the headbox can be a good indicator of the retention level. For the conventional application of a two component retention aid system, the increased filler retention correlated to impaired formation and decreased sheet strength. On the contrary, pre-flocculation led to an increase in both sheet strength and filler retention, demonstrating the advantage of pre-flocculating filler.

  • 8.
    Badal Tejedor, Maria
    et al.
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials. KTH Royal Institute of Technology, Sweden.
    Nordgren, Niklas
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials.
    Schuleit, Michael
    Novartis Pharma AG, Switzerland.
    Pazesh, Samaneh
    Uppsala University, Sweden.
    Alderborn, Göran
    Uppsala University, Sweden.
    Millqvist-Fureby, Anna
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials.
    Rutland, Mark W.
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials. KTH Royal Institute of Technology, Sweden.
    Determination of interfacial amorphicity in functional powders2017In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 33, no 4, p. 920-926Article in journal (Refereed)
    Abstract [en]

    The nature of the surfaces of particles of pharmaceutical ingredients, food powders, and polymers is a determining factor for their performance in for example tableting, powder handling, or mixing. Changes on the surface structure of the material will impact the flow properties, dissolution rate, and tabletability of the powder blend. For crystalline materials, surface amorphization is a phenomenon which is known to impact performance. Since it is important to measure and control the level of amorphicity, several characterization techniques are available to determine the bulk amorphous content of a processed material. The possibility of characterizing the degree of amorphicity at the surface, for example by studying the mechanical properties of the particles' surface at the nanoscale, is currently only offered by atomic force microscopy (AFM). The AFM PeakForce QNM technique has been used to measure the variation in energy dissipation (eV) at the surface of the particles which sheds light on the mechanical changes occurring as a result of amorphization or recrystallization events. Two novel approaches for the characterization of amorphicity are presented here. First, since particles are heterogeneous, we present a methodology to present the results of extensive QNM analysis of multiple particles in a coherent and easily interpreted manner, by studying cumulative distributions of dissipation data with respect to a threshold value which can be used to distinguish the crystalline and amorphous states. To exemplify the approach, which is generally applicable to any material, reference materials of purely crystalline α-lactose monohydrate and completely amorphous spray dried lactose particles were compared to a partially amorphized α-lactose monohydrate sample. Dissipation data are compared to evaluations of the lactose samples with conventional AFM and SEM showing significant topographical differences. Finally, the recrystallization of the surface amorphous regions in response to humidity was followed by studying the dissipation response of a well-defined surface region over time, which confirms both that dissipation measurement is a useful measure of surface amorphicity and that significant recrystallization occurs at the surface in response to humidity.

  • 9.
    Barwick, Vicki
    et al.
    LGC Ltd, UK.
    Ellison, Stephen L. R.
    LGC Ltd, UK.
    Gjengedal, Elin
    NTNU Norwegian University of Life Sciences, Norway.
    Magnusson, Bertil
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials.
    Molinier, Olivier
    Aglae, France.
    Patriarca, Marina
    Istituto Superiore di Sanità, Italy.
    Sibbesen, Lorens
    LAB Quality International, Denmark.
    Vanlaethem, Nicole
    Classes Moyennes et Energie, Belgium.
    Vercruysse, Isabelle
    Belab, Belgium.
    Method validation in analytical sciences: discussions on current practice and future challenges2017In: Accreditation and Quality Assurance, ISSN 0949-1775, E-ISSN 1432-0517, Vol. 22, no 5, p. 253-263Article in journal (Refereed)
    Abstract [en]

    Eurachem held a workshop on method validation in analytical sciences in Gent, Belgium, on 9–10 May 2016. A summary of the working group discussions is provided here. The discussions covered a range of issues concerned with current practice and future challenges in method validation, i.e. setting requirements for a method to be validated; planning validation studies; validation of qualitative and semi-quantitative methods; validation of multi-parameter methods; determination of trueness/bias; assessment of working range; validation in microbiology; and method validation under flexible scope of accreditation. Delegates (129) from 24 different countries and from different backgrounds, e.g. from both public and private laboratories, laboratory associations, accreditation bodies and universities, attended the working groups, thus providing opportunities to collect a variety of views and experiences as well as to identify potential gaps in current guidance and regulations. While the practicalities of assessing method performance characteristics are generally well understood, the issue of setting requirements for those characteristics beforehand is less straightforward. Although a number of documents addressing the principles of method validation are available, guidance on dealing with more complex and ‘non-ideal’ situations, as well as examples of good practice, would be welcomed and greater harmonisation of approaches was deemed necessary. There remains a need for guidance on both the concepts that apply to ‘qualitative’ or ‘nominal’ test methods and on the practical implementation of validation studies in such cases.

  • 10.
    Bengtsson, Jenny
    et al.
    RISE - Research Institutes of Sweden, Bioeconomy, Biobased Materials. Chalmers University of Technology, Sweden.
    Jedvert, Kerstin
    RISE - Research Institutes of Sweden, Materials and Production, IVF.
    Hedlund, Artur
    RISE - Research Institutes of Sweden, Materials and Production, IVF.
    Köhnke, Tobias
    RISE - Research Institutes of Sweden, Materials and Production, IVF.
    Theliander, Hans
    Chalmers University of Technology, Sweden.
    Mass transport and yield during spinning oflignin-cellulose carbon fiber precursors2019In: Holzforschung, ISSN 0018-3830, E-ISSN 1437-434X, Vol. 73, no 5, p. 509-516Article in journal (Refereed)
    Abstract [en]

    Lignin, a substance considered as a residue in biomass and ethanol production, has been identified as a renewable resource suitable for making inexpensive carbon fibers (CFs), which would widen the range of possible applications for light-weight CFs reinforced composites. Wet spinning of lignin-cellulose ionic liquid solutions is a promising method for producing lignin-based CFs precursors. However, wet-spinning solutions containing lignin pose technical challenges that have to be solved to enable industrialization. One of these issues is that a part of the lignin leaches into the coagulation liquid, which reduces yield and might complicate solvent recovery. In this work, the mass transport during coagulation is studied in depth using a model system and trends are confirmed with spinning trials. It was discovered that during coagulation, efflux of ionic liquid is not hindered by lignin concentration in solution and the formed cellulose network will enclose soluble lignin. Consequently, a high total concentration of lignin and cellulose in solution is advantageous to maximize yield. This work provides a fundamental understanding on mass transport during coagulation of lignin-cellulose solutions, crucial information when designing new solution-based fiber forming processes.

  • 11.
    Berg, Robert
    et al.
    RISE - Research Institutes of Sweden, Bioscience and Materials, Process och Pharmaceuticals Development.
    Bergman, Jan
    Karolinska Institute, Sweden.
    Synthesis of thieno[2,3-b]indole-2,3-diones and their ring expansions induced by diazomethane2017In: Tetrahedron, ISSN 0040-4020, E-ISSN 1464-5416, Vol. 73, no 38, p. 5654-5658Article in journal (Refereed)
    Abstract [en]

    Indole-2-thione 3 reacted quickly with oxalyl chloride to yield thieno[2,3-b]indole-2,3-dione 4 together with the isomer thiazolo[3,2-a]indole-2,3-dione 5. These thieno[2,3-b]indole-2,3diones underwent ring expansions when treated with diazomethane and e.g. thieno[2,3-b]indole-2,3-dione 4 gave the thiopyrano derivative 16, after two insertions.

  • 12. Bergenstråhle, M.
    et al.
    Wohlert, J.
    Larsson, Per Tomas
    RISE, STFI-Packforsk.
    Mazeau, K.
    Berglund, L. A.
    Dynamics of cellulose - Water interfaces: NMR spin - Lattice relaxation times calculated from atomistic computer simulations2008In: Journal of Physical Chemistry B, ISSN 1520-6106, E-ISSN 1520-5207, Journal of Physical Chemistry B, Vol. 112, no 9, p. 2590-2595Article in journal (Refereed)
    Abstract [en]

    Solid-state nuclear magnetic resonance (CP/MAS 13C NMR) spectroscopy has often been used to study cellulose structure, but some features of the cellulose NMR spectrum are not yet fully understood. One such feature is a doublet around 84 ppm, a signal that has been proposed to originate from C4 atoms at cellulose fibril surfaces. The two peaks yield different T1, differing by approximately a factor of 2 at 75 MHz. In this study, we calculate T1 from C4-H4 vector dynamics obtained from molecular dynamics computer simulations of cellulose I β-water interfacial systems. Calculated and experimentally obtained T1 values for C4 atoms in surface chains fell within the same order of magnitude, 3-20 s. This means that the applied force field reproduces relevant surface dynamics for the cellulose-water interface sufficiently well. Furthermore, a difference in T1 of about a factor of 2 in the range of Larmor frequencies 25-150 MHz was found for C4 atoms in chains located on top of two different crystallographic planes, namely, (110) and (110). A previously proposed explanation that the C4 peak doublet could derive from surfaces parallel to different crystallographic planes is herewith strengthened by computationally obtained evidence. Another suggested basis for this difference is that the doublet originates from C4 atoms located in surface anhydro-glucose units with hydroxymethyl groups pointing either inward or outward. This was also tested within this study but was found to yield no difference in calculated T1.

  • 13. Bergenstråhle-Wohlert, M.
    et al.
    Berglund, L.A.
    Brady, J.W.
    Larsson, P.T.
    RISE, Innventia.
    Westlund, P.-O.
    Wohlert, J.
    Concentration enrichment of urea at cellulose surfaces: Results from molecular dynamics simulations and NMR spectroscopy2012In: Cellulose (London), ISSN 0969-0239, E-ISSN 1572-882X, no 1, p. 1-12Article in journal (Refereed)
  • 14. Bergstrm, E.M.
    et al.
    Salmen, L.
    RISE, Innventia.
    Kochumalayil, J.
    Berglund, L.
    Plasticized xyloglucan for improved toughness: Thermal and mechanical behaviour2012In: Carbohydrate Polymers, ISSN 0144-8617, E-ISSN 1879-1344, no 4, p. 2532-2537Article in journal (Refereed)
  • 15.
    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 properties2016In: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 484, p. 279-290Article in journal (Refereed)
    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).

  • 16.
    Björklund Jansson, Marianne
    et al.
    RISE, Innventia.
    Nilvebrant, N. -O
    Wood Extractives2009In: Wood Chemistry and Wood Biotechnology, Walter de Gruyter, 2009, p. 147-171Chapter in book (Refereed)
  • 17.
    Blomqvist, Per
    et al.
    RISE - Research Institutes of Sweden, Safety and Transport.
    Sandinge, Anna
    RISE - Research Institutes of Sweden, Safety and Transport.
    Experimental evaluation of fire toxicity test methods2018Report (Other academic)
    Abstract [en]

    An experimental evaluation of the most common bench-scale tests methods for fire toxicity was conducted by RISE Fire Research. The background of the work was the on-going discussion in the fire community on the applicability and relevance of these test methods.

    The test methods included in the programme were the ISO/TS 19700 steady-state tube furnace (SSTF), the controlled atmosphere cone calorimeter (CACC), and the EN 45545-2 smoke chamber test (SC). In these tests the production of selected toxic gases was quantitatively analysed using FTIR. Tests for the measurement of toxic gas production were made with eleven different materials used as test specimens, both combustible and non-combustible materials. The materials were commercially available insulation products provided by EURIMA, the sponsor of the project. These materials should not be regarded as typical or fully representative of a product category.

    The evaluation of the results from the different test methods was divided into combustible test specimens and non-combustible test specimens. That was because the test conditions in the first case are greatly influenced by the combustion behaviour of the test specimen, while in the second case the test conditions are more constant.

    A general observation was that there in many cases was correlation between both species composition and level of toxic gas species yields between test methods when the combustion conditions were similar. In cases where yields differed significantly it could in most cases be explained by clear differences in test conditions.

    For combustible materials it was concluded that the SSTF offers the best means for conducting tests at pre-decided and controlled flaming combustion conditions. The CACC does not give steady-state flaming combustion and the influence of vitiation was limited in the tests made. The SC generally accumulates a mixture of gases from both flaming and non-flaming combustion periods in a test, and the yields measured do not in those cases represent any specific combustion stage.

    For non-combustible materials a general observation was that any of the test methods investigated in principle could be used since the influence on the test conditions from the material itself is limited compared to combustible materials. However, there were specific properties and limitations of the different test methods observed that are important to consider.

  • 18.
    Boge, Lukas
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Life Science. Chalmers University of Technology, Sweden.
    Bysell, Helena
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Life Science.
    Ringstad, Lovisa
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Life Science.
    Wennman, David
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Process Development, Analys och fastfas.
    Umerska, Anita
    University of Angers, France.
    Cassisa, Viviane
    CHU Angers, France.
    Eriksson, Jonny
    Uppsala University, Sweden.
    Joly-Guillou, Marie-Laure
    CHU Angers, France.
    Edwards, Katarina
    Uppsala University, Sweden.
    Andersson, Martin
    Chalmers University of Technology, Sweden.
    Lipid-based liquid crystals as carriers for antimicrobial peptides: Phase behavior and antimicrobial effect2016In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 32, no 17, p. 4217-4228Article in journal (Refereed)
    Abstract [en]

    The number of antibiotic-resistant bacteria is increasing worldwide, and the demand for novel antimicrobials is constantly growing. Antimicrobial peptides (AMPs) could be an important part of future treatment strategies of various bacterial infection diseases. However, AMPs have relatively low stability, because of proteolytic and chemical degradation. As a consequence, carrier systems protecting the AMPs are greatly needed, to achieve efficient treatments. In addition, the carrier system also must administrate the peptide in a controlled manner to match the therapeutic dose window. In this work, lyotropic liquid crystalline (LC) structures consisting of cubic glycerol monooleate/water and hexagonal glycerol monooleate/oleic acid/water have been examined as carriers for AMPs. These LC structures have the capability of solubilizing both hydrophilic and hydrophobic substances, as well as being biocompatible and biodegradable. Both bulk gels and discrete dispersed structures (i.e., cubosomes and hexosomes) have been studied. Three AMPs have been investigated with respect to phase stability of the LC structures and antimicrobial effect: AP114, DPK-060, and LL-37. Characterization of the LC structures was performed using small-angle X-ray scattering (SAXS), dynamic light scattering, ζ-potential, and cryogenic transmission electron microscopy (Cryo-TEM) and peptide loading efficacy by ultra performance liquid chromatography. The antimicrobial effect of the LCNPs was investigated in vitro using minimum inhibitory concentration (MIC) and time-kill assay. The most hydrophobic peptide (AP114) was shown to induce an increase in negative curvature of the cubic LC system. The most polar peptide (DPK-060) induced a decrease in negative curvature while LL-37 did not change the LC phase at all. The hexagonal LC phase was not affected by any of the AMPs. Moreover, cubosomes loaded with peptides AP114 and DPK-060 showed preserved antimicrobial activity, whereas particles loaded with peptide LL-37 displayed a loss in its broad-spectrum bactericidal properties. AMP-loaded hexosomes showed a reduction in antimicrobial activity.

  • 19.
    Boge, Lukas
    et al.
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. Chalmers University of Technology, Sweden.
    Hallstensson, Karin
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Ringstad, Lovisa
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation.
    Johansson, Jenny
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials.
    Andersson, Therese
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials.
    Davoudi, Mina
    Lund University, Sweden.
    Larsson, Tomas
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials.
    Mahlapuu, Margit
    Promore Pharma AB, Sweden; University of Gothenburg, Sweden.
    Håkansson, Joakim
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry and Materials.
    Andersson, Martin
    Chalmers University of Technology, Sweden.
    Cubosomes for topical delivery of the antimicrobial peptide LL-372019In: European journal of pharmaceutics and biopharmaceutics, ISSN 0939-6411, E-ISSN 1873-3441, Vol. 134, p. 60-67Article in journal (Refereed)
    Abstract [en]

    In this study, the use of cubosomes for topical delivery of the antimicrobial peptide (AMP) LL-37 was investigated. Topical delivery of AMPs is of great interest for treatment of skin infections caused by bacteria, such as Staphylococcus aureus. AMP containing cubosomes were produced by three different preparation protocols and compared: (i) pre-loading, where LL-37 was incorporated into a liquid crystalline gel, which thereafter was dispersed into nanoparticles, (ii) post-loading, where LL-37 was let to adsorb onto pre-formed cubosomes, and (iii) hydrotrope-loading, where LL-37 was incorporated during the spontaneously formed cubosomes in an ethanol/glycerol monooleate mixture. Particle size and size distribution were analyzed using dynamic light scattering (DLS), liquid crystalline structure by small angle x-ray scattering (SAXS) and release of LL-37 by a fluorescamine assay. Proteolytic protection of LL-37 as well as bactericidal effect after enzyme exposure was investigated. The skin irritation potential of cubosomes was examined by an in vitro epidermis model. Finally, the bacterial killing property of the cubosomes was examined by an ex vivo pig skin wound infection model with Staphylococcus aureus. Data showed that a high loading of LL-37 induced formation of vesicles in case of cubosomes prepared by sonication (pre-loading). No release of LL-37 was observed from the cubosomes, indicating strong association of the peptide to the particles. Proteolysis studies showed that LL-37 was fully protected against enzymatic attacks while associated with the cubosomes, also denoting strong association of the peptide to the particles. As a consequence, bactericidal effect after enzyme exposure remained, compared to pure LL-37 which was subjected to proteolysis. No skin irritation potential of the cubosomes was found, thus enabling for topical administration. The ex vivo wound infection model showed that LL-37 in pre-loaded cubosomes killed bacteria most efficient.

  • 20.
    Bradley, Siobhan J.
    et al.
    Victoria University of Wellington, New Zealand.
    Kroon, Renee
    Chalmers University of Technology, Sweden.
    Laufersky, Geoffry
    Victoria University of Wellington, New Zealand.
    Röding, Magnus
    RISE - Research Institutes of Sweden, Bioscience and Materials, Agrifood and Bioscience.
    Goreham, Renee V.
    Victoria University of Wellington, New Zealand.
    Gschneidtner, Tina
    Chalmers University of Technology, Sweden.
    Schroeder, Kathryn
    Victoria University of Wellington, New Zealand.
    Moth-Poulsen, Kasper
    Chalmers University of Technology, Sweden.
    Andersson, Mats
    Chalmers University of Technology, Sweden ; University of South Australia, Australia.
    Nann, Thomas
    Victoria University of Wellington, New Zealand.
    Heterogeneity in the fluorescence of graphene and graphene oxide quantum dots2017In: Microchimica Acta, ISSN 0026-3672, E-ISSN 1436-5073, Vol. 184, no 3, p. 871-878Article in journal (Refereed)
    Abstract [en]

    Heterogeneity is an inherent property of a wealth of real-world nanomaterials and yet rarely in the reporting of new properties is its effect sufficiently addressed. Graphene quantum dots (GQDs) – fluorescent, nanoscale fragments of graphene - are an extreme example of a heterogeneous nanomaterial. Here, top-down approaches – by far the most predominant – produce batches of particles with a distribution of sizes, shapes, extent of oxidation, chemical impurities and more. This makes characterization of these materials using bulk techniques particularly complex and comparisons of properties across different synthetic methods uninformative. In particular, it hinders the understanding of the structural origin of their fluorescence properties. We present a simple synthetic method, which produces graphene quantum dots with very low oxygen content that can be suspended in organic solvents, suggesting a very pristine material. We use this material to illustrate the limitations of interpreting complex data sets generated by heterogeneous materials and we highlight how misleading this “pristine” interpretation is by comparison with graphene oxide quantum dots synthesized using an established protocol. In addition, we report on the solvatochromic properties of these particles, discuss common characterization techniques and their limitations in attributing properties to heterogeneous materials.

  • 21.
    Brodin, Ida
    et al.
    RISE, Innventia.
    Ernstsson, Marie
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Sveriges tekniska forskningsinstitut, YKI – Ytkemiska institutet.
    Gellerstedt, Göran
    RISE, Innventia.
    Sjöholm, Elisabeth
    RISE, Innventia.
    Oxidative stabilisation of kraft lignin for carbon fibre production2012In: Holzforschung, ISSN 0018-3830, E-ISSN 1437-434X, no 2, p. 141-147Article in journal (Refereed)
    Abstract [en]

    With the aim of investigating kraft lignin as a raw material for carbon fibre production, different lignins have been stabilised in air at conditions varied according to a full factorial experimental design. The lignins under examination were purified kraft lignin powders originating from birch, spruce/pine and Eucalyptus globules, as well as lignin fibres originating from birch with 5 poly(ethylene oxide) (PEO) added as a plasticiser. The influence of temperature, time and heating rate on yield and glass-transition temperature (Tg) was investigated. The highest yield was achieved after stabilisation at 280°C during 2h with a heating rate of 0.2°C min -1. The Tg of all lignin powders was increased when stabilisation occurred under harsher conditions. X-ray photoelectron spectroscopy analysis (XPS) of both the outer surface and the cleaved cross-section of individual lignin/PEO fibres showed a clear gradient in the degree of chemical modification, with the major change occurring on the surface resulting in the appearance of a skin-core structure after stabilisation. The behaviour of the lignin fibres during stabilisation is similar to that of pitch-based fibres, indicating good possibilities for lignin as raw material for carbon fibre production.

  • 22.
    Carlred, Louise
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Medicinteknik. Chalmers University of Technology, Sweden.
    Vukojević, Vladana
    Karolinska Institute, Sweden.
    Johansson, Björn
    Karolinska Institute, Sweden.
    Schalling, Martin
    Karolinska Institute, Sweden.
    Höök, Fredrik
    Chalmers University of Technology, Sweden.
    Sjövall, Peter
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Medicinteknik. Chalmers University of Technology, Sweden.
    Imaging of amyloid-β in alzheimer’s disease transgenic mouse brains with ToF-SIMS using immunoliposomes2016In: Biointerphases, ISSN 1934-8630, E-ISSN 1559-4106, Vol. 11, no 2, p. 1-11, article id 02A312Article in journal (Refereed)
    Abstract [en]

    Time-of-flight secondary ion mass spectrometry (ToF-SIMS) has been proven to successfully image different kinds of molecules, especially a variety of lipids, in biological samples. Proteins, however, are difficult to detect as specific entities with this method due to extensive fragmentation. To circumvent this issue, the authors present in this work a method developed for detection of proteins using antibody-conjugated liposomes, so called immunoliposomes, which are able to bind to the specific protein of interest. In combination with the capability of ToF-SIMS to detect native lipids in tissue samples, this method opens up the opportunity to analyze many different biomolecules, both lipids and proteins, at the same time, with high spatial resolution. The method has been applied to detect and image the distribution of amyloid-β (Aβ), a biologically relevant peptide in Alzheimer’s disease (AD), in transgenic mouse brain tissue. To ensure specific binding, the immunoliposome binding was verified on a model surface using quartz crystal microbalance with dissipation monitoring. The immunoliposome binding was also investigated on tissue sections with fluorescence microscopy, and compared with conventional immunohistochemistry using primary and secondary antibodies, demonstrating specific binding to Aβ. Using ToF-SIMS imaging, several endogenous lipids, such as cholesterol and sulfatides, were also detected in parallel with the immunoliposome-labeled Aβ deposits, which is an advantage compared to fluorescence microscopy. This method can thus potentially provide further information about lipid–protein interactions, which is important to understand the mechanisms of neurodegeneration in AD.

  • 23. Carrick, C.
    et al.
    Lindström, S.B.
    Larsson, P.T.
    RISE, Innventia.
    Wågberg, L.
    Lightweight, highly compressible, noncrystalline cellulose capsules2014In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 30, no 26, p. 7635-6744Article in journal (Refereed)
  • 24. Carrick, C.
    et al.
    Ruda, M.
    Pettersson, B.
    Larsson, P.T.
    RISE, Innventia.
    Wågberg, L.
    Hollow cellulose capsules from CO2 saturated cellulose solutions: Their preparation and characterization2013In: RSC Advances, ISSN  2046-2069, no 7, p. 2462-2469Article in journal (Refereed)
  • 25.
    Charlène, Reverdy
    et al.
    CNRS, France; Grenoble Institute of Technology, France.
    Sedighi Moghaddam, Maziar
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Material och ytteknik.
    Sundin, Mikael
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Material och ytteknik.
    Swerin, Agne
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Material och ytteknik.
    Julien, Bras
    CNRS, France; Grenoble Institute of Technology, France.
    Superhydrophobic surfaces manufacturing with nanocellulose2016In: N.I.C.E. 2016 - The 3rd International Conference on Bioinspired and Biobased Chemistry & Materials, 2016Conference paper (Refereed)
    Abstract [en]

    Researchers in natural fibers see opportunities in superhydrophobicity for fabrics or paper. The first challenge with natural fiber is their high hydrophilicity when the second is the perpetual search for water born coating  in papermaking. These challenges were overcome by a one pot formulation comprising a latex binder, precipitated calcium carbonate and  fatty acids to give their hydrophobicity to pigments 1.  In this study, we want to go further by replacing the petro-sourced latex with a new kind of fibers that are cellulose nanofibers (CNF).

    Inspired by the Lotus leaf, superhydrophobic surfaces have been a center of interest in the last decade because of their high potential in industry for a variety of applications.  It is seen as the next generation of surface for anti-fouling and corrosive retardant in navy industry but also  in general  anti corrosive materials industry.  Now widely studied , mechanisms for manufacturing superhydrophobicity are well understood. Born from the alliance of low surface energy chemistry and physical structuration of surface, superhydrophobic materials give a water contact angle above 150° and a slidding angle below 10°.

  • 26.
    Chedid, Fadia
    et al.
    RISE, Innventia.
    Aldaeus, Fredrik
    RISE, Innventia.
    Jacobs, Anna
    RISE, Innventia.
    Lignin molecular mass determined using size-exclusion chromatography and MALDI-TOF mass spectrometry2014Conference paper (Refereed)
  • 27.
    Colombo, Stefan
    et al.
    Uppsala University, Sweden.
    Brisander, Magnus
    XSpray Microparticles AB, Sweden.
    Haglöf, Jakob
    Uppsala University, Sweden.
    Sjövall, Peter
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Medicinteknik.
    Andersson, Per
    XSpray Microparticles AB, Sweden.
    Østergaard, Jesper
    University of Copenhagen, Denmark.
    Malmsten, Martin
    Uppsala University, Sweden.
    Matrix effects in nilotinib formulations with pH-responsive polymer produced by carbon dioxide-mediated precipitation2015In: International Journal of Pharmaceutics, ISSN 0378-5173, E-ISSN 1873-3476, Vol. 494, no 1, p. 205-217, article id 15114Article in journal (Refereed)
    Abstract [en]

    Factors determining the pH-controlled dissolution kinetics of nilotinib formulations with the pH-titrable polymer hydroxypropyl methylcellulose phthalate, obtained by carbon dioxide-mediated precipitation, were mechanistically examined in acid and neutral environment. The matrix effect, modulating the drug dissolution, was characterized with a battery of physicochemical methodologies, including ToF-SIMS for surface composition, SAXS/WAXS and modulated DSC for crystallization characterization, and simultaneous UV-imaging and Raman spectroscopy for monitoring the dissolution process in detail. The hybrid particle formulations investigated consisted of amorphous nilotinib embedded in a polymer matrix in single continuous phase, displaying extended retained amorphicity also under wet conditions. It was demonstrated by Raman and FTIR spectroscopy that the efficient drug dispersion and amorphization in the polymer matrix were mediated by hydrogen bonding between the drug and the phthalate groups on the polymer. Simultaneous Raman and UV-imaging studies of the effect of drug load on the swelling and dissolution of the polymer matrix revealed that high nilotinib load prevented matrix swelling on passage from acid to neutral pH, thereby preventing re-precipitation and re-crystallization of incorporated nilotinib. These findings provide a mechanistic foundation of formulation development of nilotinib and other protein kinase inhibitors, which are now witnessing an intense therapeutic and industrial attention due to the difficulty in formulating these compounds so that efficient oral bioavailability is reached.

  • 28.
    Cong, Jiayan
    et al.
    KTH Royal Institute of Technology, Sweden.
    Kinschel, Dominik
    KTH Royal Institute of Technology, Sweden; Dyenamo AB, Sweden.
    Daniel, Quentin
    KTH Royal Institute of Technology, Sweden.
    Safdari, Majid
    KTH Royal Institute of Technology, Sweden.
    Gabrielsson, Erik
    Dyenamo AB, Sweden.
    Chen, Hong
    KTH Royal Institute of Technology, Sweden.
    Svensson, Per H.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Process Development, Analys och fastfas. KTH Royal Institute of Technology, Sweden.
    Sun, Licheng
    KTH Royal Institute of Technology, Sweden; DUT Dalian University of Technology, China.
    Kloo, Lars
    KTH Royal Institute of Technology, Sweden.
    Bis(1,1-bis(2-pyridyl)ethane)copper(I/II) as an efficient redox couple for liquid dye-sensitized solar cells2016In: Journal of Materials Chemistry, ISSN 0959-9428, E-ISSN 1364-5501, Vol. 4, no 38, p. 14550-14554Article in journal (Refereed)
    Abstract [en]

    A new redox couple, [Cu(bpye)2]+/2+, has been synthesized, and applied in dye-sensitized solar cells (DSSCs). Overall efficiencies of 9.0% at 1 sun and 9.9% at 0.5 sun were obtained, which are considerably higher than those obtained for cells containing the reference redox couple, [Co(bpy)3]2+/3+. These results represent a record for copper-based complex redox systems in liquid DSSCs. Fast dye regeneration, sluggish recombination loss processes, faster electron self-exchange reactions and suitable redox potentials are the main reasons for the observed increase in efficiency. In particular, the main disadvantage of cobalt complex-based redox couples, charge-transport problems, appears to be resolved by a change to copper complex redox couples. The results make copper complex-based redox couples very promising for further development of highly efficient DSSCs.

  • 29.
    Cooper, Peter K.
    et al.
    University of Newcastle, Australia.
    Li, Hua
    University of Newcastle, Australia.
    Rutland, Mark W.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Life Science. KTH Royal Institute of Technology, Sweden.
    Webber, Grant B.
    University of Newcastle, Australia.
    Atkin, Rob
    University of Newcastle, Australia.
    Tribotronic control of friction in oil-based lubricants with ionic liquid additives2016In: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 18, no 34, p. 23657-23662Article in journal (Refereed)
    Abstract [en]

    Atomic force microscopy (AFM) reveals that tribotronic control of friction using an external potential applied to a gold surface is possible for ionic liquid (IL) concentrations as low as 5 mol% in hexadecane. The IL used is trihexyl(tetradecyl)phosphonium bis(2,4,4-trimethylpentyl)phosphinate, in which both the cation and anion have surfactant-like structures, and is miscible with hexadecane in all proportions. For IL concentrations less than 5 mol% friction does not vary with applied potential, but for 5 mol% and above changing the potential changes the composition of the IL boundary layer from cation-enriched (negative potentials) to anion-enriched (positive potentials). As the lubricities of the cation-rich and anion-rich boundary layers differ, this enables active control of friction in oil-based lubricants.

  • 30.
    Dahlman, Olof
    et al.
    STFI.
    Jacobs, Anna
    STFI.
    Liljenberg, Annika
    STFI.
    Ismail Olsson, Asha
    STFI.
    Analysis of carbohydrates in wood and pulps employing enzymatic hydrolysis and subsequent capillary zone electrophoresis2000In: Journal of Chromatography A, ISSN 0021-9673, E-ISSN 1873-3778, Vol. 891, no 1, p. 157-174Article in journal (Refereed)
  • 31.
    Dalvi-Isfahan, Mohsen
    et al.
    Isfahan University of Technology, Iran.
    Hamdami, Nasser
    Isfahan University of Technology, Iran.
    Xanthakis, Epameinondas
    RISE - Research Institutes of Sweden, Bioscience and Materials, Agrifood and Bioscience.
    Le-Bail, Alain
    UMR GEPEA, France.
    Review on the control of ice nucleation by ultrasound waves, electric and magnetic fields2017In: Journal of Food Engineering, ISSN 0260-8774, E-ISSN 1873-5770, Vol. 195, p. 222-234Article in journal (Refereed)
    Abstract [en]

    Freezing is the most popular and widely used food preservation method of the modern times. The freezing process of food matrices is related to their high water content and its metamorphoses into ice on cooling. The final quality of the frozen product is highly depended on the ice crystal morphology because it can cause irreversible damage on the microstructure of the food matrix. Supercooling and ice nucleation temperature need to be controlled both in suppressing and inducing the solidification to improve technological processes such as freeze drying, freeze concentration, cryopreservation, ice formation and cold-energy storage both in food industry and domestic preservation. However, the mechanism of freezing is not yet well known and it is affected by several factors. Several emerging technologies have been recently proposed for ice nucleation control during freezing. This review article is focused on the alternative freezing methods such as ultrasound waves, magnetic, electric, and electromagnetic field assisted freezing. In addition, the properties, mechanism of action and possible applications of electrofreezing are extensively discussed.

  • 32. Dammström, S.
    et al.
    Salmen, Lennart
    RISE, STFI-Packforsk.
    Gatenholm, P.
    On the interactions between cellulose and xylan, a biomimetic simulation of the hardwood cell wall2009In: BioResources, ISSN 1930-2126, E-ISSN 1930-2126, Vol. 4, no 1, p. 3-14Article in journal (Refereed)
    Abstract [en]

    The plant cell wall exhibits a hierarchical structure, in which the organization of the constituents on different levels strongly affects the mechanical properties and the performance of the material. In this work, the interactions between cellulose and xylan in a model system consisting of a bacterial cellulose/glucuronoxylan (extracted from aspen, Populus tremula) have been studied and compared to that of a delignified aspen fiber material. The properties of the materials were analyzed using Dynamical Mechanical Analysis (DMA) with moisture scans together with dynamic Infra Red -spectroscopy at dry and humid conditions. The results showed that strong interactions existed between the cellulose and the xylan in the aspen holocellulose. The same kinds of interactions were seen in a water-extracted bacterial cellulose/xylan composite, while unextracted material showed the presence of xylan not interacting with the cellulose. Based on these findings for the model system, it was suggested that there is in hardwood one fraction of xylan that is strongly associated with the cellulose, taking a similar role as glucomannan in softwood.

  • 33.
    de la Motte, Hanna
    et al.
    RISE - Research Institutes of Sweden, Bioeconomy, Biorefinery and Energy.
    Palme, Anna
    Chalmers University of Technology, Sweden.
    The development of the Blend Re:windprocess2018Report (Other academic)
  • 34.
    Dedic, D.
    et al.
    RISE, Innventia.
    Iversen, T.
    RISE, Innventia.
    Ek, M.
    Cellulose degradation in the Vasa: The role of acids and rust2013In: Studies in Conservation, ISSN 0039-3630, E-ISSN 2047-0584, no 4, p. 308-313Article in journal (Refereed)
  • 35.
    Dedic, D.
    et al.
    RISE, Innventia.
    Iversen, T.
    RISE, Innventia.
    Sandberg, T.
    Ek, M.
    Chemical analysis of wood extractives and lignin in the oak wood of the 380 year old Swedish warship vasa2011Conference paper (Refereed)
  • 36.
    Dedic, Dina
    et al.
    RISE, Innventia.
    Iversen, Tommy
    RISE, Innventia.
    Ek, M.
    Cellulose degradation in the Vasa: The role of acids and rust2013In: Studies in Conservation, ISSN 0039-3630, E-ISSN 2047-0584, Vol. 58, no 4, p. 308-313Article in journal (Refereed)
    Abstract [en]

    The oak timbers of the Swedish warship Vasa are deteriorating. High amounts of oxalic acid have been found along with a low pH and low molecular weight cellulose deep in the wood timbers. The iron-rich surface wood differs from the interior wood in that it displays higher pH and cellulose with higher molecular weight. The objective of this study was to determine why there is a difference in cellulose degradation, pH, and oxalic acid amount between the surface region and the interior of the Vasa timbers. Analysis of cellulose weight average molecular weight by size exclusion chromatography was performed, as well as quantification of oxalic acid and iron by high-performance anion exchange chromatography and atomic emission spectroscopy, respectively. It was found that a decrease in iron content coincides with an increase in oxalic acid concentration and a drop in pH at a certain depth from the wood surface. When iron-rich surface wood samples from the Vasa were mixed with an aqueous solution of oxalic acid, a fast increase of pH over time was observed. Neither interior wood poor in iron nor the fresh oak reference showed the same neutralizing effect during the time of measurement. This indicates that the presence of iron (rust) causes a neutralization of the wood, through the formation of iron(III) oxalato complexes, thus protecting the wood from oxalic acid hydrolysis. This effect was not observed to the same extent for other acids observed in Vasa wood (sulfuric, formic, glycolic, and acetic acids).

  • 37.
    Ehmcke, Gabriele
    et al.
    Technical University of Munich, Germany.
    Pilgård, Annica
    RISE, SP – Sveriges Tekniska Forskningsinstitut. Technical University of Munich, Germany.
    Koch, Gerald
    Thünen Institute of Wood Research, Germany.
    Richter, Klaus
    Technical University of Munich, Germany.
    Improvement of a method for topochemical investigations of degraded furfurylated wood2016In: International Wood Products Journal, ISSN 2042-6445, E-ISSN 2042-6453, Vol. 7, no 2, p. 96-101Article in journal (Refereed)
    Abstract [en]

    Today there is an increasing demand for wood protection systems which are based on low environmental impact technologies. The aim of this study was to improve a method for investigating furfurylated Pinus radiata, both in terms of the furfuryl alcohol polymerisation process in the wood cell wall and the detection of initial signs of brown rot degradation. It is an established theory today that brown rot degradation starts with lignin modification in the outermost part of the secondary cell wall and the combined middle lamella. We adapted a method (cellular UV microspectrophotometry, UMSP) which enables direct imaging of the lignin distribution and modification within individual cell wall layers. Furfurylated P. radiata, incubated with Postia placenta, were scanned with monochromatic UV-light at 280 nm. The results showed that USMP is a promising method to study furfurylated wood and early fungal degradation damages in the cell wall of furfurylated wood.

  • 38.
    Ejenstam, Lina
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Polymer och fiber. KTH Royal Institute of Technology, Sweden.
    Swerin, Agne
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Material och ytteknik. KTH Royal Institute of Technology, Sweden.
    Claesson, Per M.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Material och ytteknik. KTH Royal Institute of Technology, Sweden.
    Toward superhydrophobic polydimethylsiloxane−silica particle coatings2016In: Journal of Dispersion Science and Technology, ISSN 0193-2691, E-ISSN 1532-2351, Vol. 37, no 9, p. 1375-1383Article in journal (Refereed)
    Abstract [en]

    Hydrophobized silica nanoparticles of different sizes, from 16 to 500 nm, were used to impart roughness to a hydrophobic polydimethylsiloxane (PDMS) coating with the aim of obtaining superhydrophobic properties. The particle silanization process and the curing process of the PDMS coating were optimized to increase the contact angle (CA) of the particle containing coating. The evaluation of the coatings, by means of water CA measurements and scanning electron microscopy imaging, shows that superhydrophobicity in the adhesive rose state was achieved using combinations of two differently sized particles, with an excess of the small 16 nm ones. Superhydrophobicity in the lotus state was obtained when the filler concentration of 16 nm particles was 40 wt%, but under such conditions the coating was found to partially crack, which is detrimental in barrier applications. The preference for the rose wetting state can be explained by the round shape of the particles, which promotes the superhydrophobic rose wetting state over that of the superhydrophobic lotus state.

  • 39.
    Ejenstam, Lina
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Polymer och fiber. KTH Royal Institute of Technology, Sweden.
    Swerin, Agne
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Material och ytteknik. KTH Royal Institute of Technology, Sweden.
    Pan, Jinshan
    KTH Royal Institute of Technology, Sweden.
    Claesson, Per M.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Material och ytteknik. KTH Royal Institute of Technology, Sweden.
    Corrosion protection by hydrophobic silica particle-polydimethylsiloxane composite coatings2015In: Corrosion Science, ISSN 0010-938X, E-ISSN 1879-0496, Vol. 99, p. 89-97Article in journal (Refereed)
    Abstract [en]

    In this study, the time-dependent corrosion protection ability of 10-15. μm thin polydimethylsiloxane-nanoparticle composite coatings was evaluated using mainly open circuit potential and electrochemical impedance spectroscopy measurements. The best result was obtained for the coating containing 20. wt% hydrophobic silica nanoparticles, where it was possible to achieve protection for almost 80 days in 3. wt% NaCl solution. The protective properties offered by this coating are suggested to be due to a synergistic effect of the hydrophobicity of the polydimethylsiloxane matrix and the prolonged diffusion path caused by addition of hydrophobic silica particles.

  • 40.
    Ejenstam, Lina
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Polymer och fiber. KTH Royal Institute of Technology, Sweden.
    Tuominen, Mikko
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Material och ytteknik.
    Haapanen, Janne
    Tampere University of Technology, Finland.
    Mäkelä, Jyrki M.
    Tampere University of Technology, Finland.
    Pan, Jinshan
    KTH Royal Institute of Technology, Sweden.
    Swerin, Agne
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Material och ytteknik. KTH Royal Institute of Technology, Sweden.
    Claesson, Per M.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Material och ytteknik. KTH Royal Institute of Technology, Sweden.
    Long-term corrosion protection by a thin nano-composite coating2015In: Applied Surface Science, ISSN 0169-4332, E-ISSN 1873-5584, Vol. 357, no Part B, p. 2333-2342Article in journal (Refereed)
    Abstract [en]

    We report and discuss the corrosion protective properties of a thin nano-composite coating system consisting of an 11μm thick polyester acrylate (PEA) basecoat, covered by an approximately 1-2μm thick layer of TiO2 nanoparticles carrying a 0.05μm thick hexamethyl disiloxane (HMDSO) top coat. The corrosion protective properties were evaluated on carbon steel substrates immersed in 3wt% NaCl solution by open circuit potential (OCP) and electrochemical impedance spectroscopy (EIS) measurements. The protective properties of each layer, and of each pair of layers, were also evaluated to gain further understanding of the long-term protective properties offered by the nano-composite coating. The full coating system showed excellent corrosion protective properties in the corrosive environment of 3wt% NaCl-solution for an extended period of 100 days, during which the coating impedance, at the lower frequency limit (0.01Hz), remained above 108 Ωcm2. We suggest that the excellent corrosion protective properties of the complete coating system is due to a combination of (i) good adhesion and stability of the PEA basecoat, (ii) the surface roughness and the elongated diffusion path provided by the addition of TiO2 nanoparticles, and (iii) the low surface energy provided by the HMDSO top coat.

  • 41.
    Eneborg, Alexander
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. KTH Royal Institute of Technology, Sweden.
    Improvement and Characterization of Aqueous Graphene Dispersions2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Graphene has many outstanding properties which make it a prime candidate for new technology. At the current time it is very difficult and expensive to produce large sheets of graphene, but there are many applications where that is not necessary and smaller flakes of graphene can be used instead. A practical way of handling these graphene flakes is in a dispersion, especially a water-based dispersion have many benefits. Such a stable dispersion of functionalized graphene is produced, improved, and characterized in this project. An aqueous system that was developed in two previous M.Sc. theses, each determining a suitable graphene powder and stabilizer, was used as a starting point with the main purpose being to improve the yield. The method used to produce these dispersions can be described as sonicating graphene powder in a solution of water and stabilizer followed by centrifuging to remove un-dispersed graphene particles. Experiments were carried out examining the possibility of dispersing those previously undispersed graphene flakes, combining the stabilizer with several surfactants, optimizing the centrifuge speed and time, refining the sonication procedure with longer exposure time and cooling, narrowing the size-distribution of the original stabilizer through ultrafiltration, and removing excessive unbound stabilizer through ultrafiltration. Samples were characterized with UV-vis, SEM, TGA, Electrophoretic light scattering, and Laser diffraction spectroscopy. It was discovered that the yield from the graphene powder was heavily dependent on sonication time and centrifugation conditions. The gain from increasing sonication time showed that most, if not all, of the un-dispersed graphene flakes previously considered lost could in fact be dispersed. In an industrial setting any un-dispersed flakes could simply be added to the next batch. Reducing the centrifugation speed as well as time increased the concentration of graphene to more than twice as high, and that gain comes solely from the larger graphene flakes. Thusly the previous problem with a low yield was shown to have been caused by too little sonication and too much centrifugation. The particle size analysis did show a small reduction in flake size as the sonication time was increased, but when those dispersions were characterized in SEM they all formed even films with no discernable difference between them. Purifying the scaled up dispersions by removing excess stabilizer through ultrafiltration was performed to three different degrees, 0 %, 50 % and 95 %, for a total of three dispersions of 100ml. All three dispersions were shown to be highly stable, with no apparent reduction in graphene concentration over 5 weeks and a zeta potential averaging below -50mV. The TGA results reinforce the UV-vis results, proving that the purification worked as intended.

  • 42.
    Falk, Julia
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. Uppsala University, Sweden.
    Freeze-drying of protein pharmaceutical in vials with different character2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Freeze-drying of protein pharmaceuticals is a procedure frequently used to obtain stability of the active pharmaceutical ingredientduring distribution and storage. It can be performed in pre-filled syringes, with a lubricous coating of silicone on the inside, to enable the piston moving. The coating changes the environment potentially affecting the features of the freeze-dried cake since the wetting behavior and adhesion to the inner wall is affected.This project aimed to investigate the effect of the siliconization of the cakes. Three different formulations were freeze-dried in nonsiliconized (NS) and siliconized vials using different siliconization protocols. Analysis was done using differential scanning calorimetry (DSC), thermal gravimetric analysis (TGA),scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and an embedding method, intended to give information about the cake’s shrinkage, cracking and pore-structure. The water content in the bottom of the cakes was consistently higher than in the top, a difference decreasing over time. Increased surface hydrophobicity lead to increased shrinkage of the cake’s volume and a decrease in fogging. The bottom of the protein cake in the vial siliconized with a commercial silicone emulsion consisted of pores with regularly equal pore size and thick pore walls, a structure not seen in any other cake. All cakes in the silicone emulsion siliconized vials had lower water content than the cakes in the vials using the other siliconization method. The XPS-analysis showed that the cakes in the emulsion siliconized vials contained silicon, indicating an excess of silicone when siliconizing and/or an unstable coating.

  • 43.
    Ferraris, M.
    et al.
    Politecnico di Torino, Italy.
    Perero, S.
    Politecnico di Torino, Italy.
    Ferraris, S.
    Politecnico di Torino, Italy.
    Miola, M.
    Politecnico di Torino, Italy.
    Vernè, E.
    Politecnico di Torino, Italy.
    Skoglund, S.
    KTH Royal Institute of Technology, Sweden.
    Blomberg, Eva
    RISE - Research Institutes of Sweden, Bioscience and Materials, Chemistry, Materials and Surfaces. KTH Royal Institute of Technology, Sweden.
    Odnevall Wallinder, I.
    KTH Royal Institute of Technology, Sweden.
    Antibacterial silver nanocluster/silica composite coatings on stainless steel2017In: Applied Surface Science, ISSN 0169-4332, E-ISSN 1873-5584, Vol. 396, p. 1546-1555Article in journal (Refereed)
    Abstract [en]

    A coating made of silver nanocluster/silica composites has been deposited, via a radio frequency (RF) co-sputtering technique, for the first time onto stainless steel (AISI 304L) with the aim to improve its antibacterial properties. Different thermal treatments after coating deposition have been applied in order to optimize the coating adhesion, cohesion and its antibacterial properties. Its applicability has been investigated at realistic conditions in a cheese production plant. The physico-chemical characteristics of the coatings have been analyzed by means of different bulk and surface analytical techniques. Field emission scanning electron microscopy (FESEM), X-ray Photoelectron Spectroscopy (XPS), contact angle measurements and atomic force microscopy (AFM) were employed to assess coating morphology, composition, surface roughness, wetting properties, size and local distribution of the nanoparticles within the coating. Tape tests were used to determine the adhesion/cohesion properties of the coating. The amount and time-dependence of released silver in solutions of acetic acid, artificial water, artificial tap water and artificial milk were determined by means of Atomic Absorption Spectroscopy (AAS). The antibacterial effect of the coating was evaluated at different experimental conditions using a standard bacterial strain of Staphylococcus aureus in compliance with National Committee for Clinical Laboratory Standards (NCCLS) and AATCC 147 standards. The Ahearn test was performed to measure the adhesion of bacteria to the coated stainless steel surface compared with a control surface. The antibacterial coating retained its antibacterial activity after thermal treatment up to 450 °C and after soaking in common cleaning products for stainless steel surfaces used for e.g. food applications. The antibacterial capacity of the coating remained at high levels for 1-5 days, and showed a good capacity to reduce the adhesion of bacteria up to 30 days. Only a few percent of silver in the coating was released into acetic acid, even after 10 days of exposure at 40 °C. Most silver (> 90%) remained also in the coating even after 240 h of continuous exposure. Similar observations were made after repeated exposure at 100 °C. Very low levels of released silver in solution were observed in artificial milk. No release of silver nanoparticles was observed either in synthetic tap water or in artificial milk at given conditions. The coating further displayed good antibacterial properties also when tested during working conditions in a cheese production plant.

  • 44.
    Fjellgaard Mikalsen, Ragni
    RISE - Research Institutes of Sweden, Safety and Transport, Fire Research Norway. Western Norway University of Applied Sciences, Norway; Otto von Guericke University Magdeburg, Germany.
    Fighting flameless fires: Initiating and extinguishing self-sustainedsmoldering fires in wood pellets2018Doctoral thesis, monograph (Other academic)
    Abstract [en]

    Smoldering fires represent domestic, environmental and industrial hazards. This flameless form of combustion is more easily initiated than flaming, and is also more persistent and difficult to extinguish. The growing demand for non-fossil fuels has increased the use of solid biofuels such as biomass. This represents a safety challenge, as biomass self-ignition can cause smoldering fires, flaming fires or explosions.

    Smoldering and extinguishment in granular biomass was studied experimentally. The set-up consisted of a cylindrical fuel container of steel with thermally insulated side walls. The container was closed at the bottom, open at the top and heated from below by a hot surface. Two types of wood pellets were used as fuel, with 0.75-1.5 kg samples.

    Logistic regression was used to determine the transition region between non-smoldering and self-sustained smoldering experiments, and to determine the influence of parameters. Duration of external heating was most important for initiation of smoldering. Sample height was also significant, while the type of wood pellet was near-significant and fuel container height was not.

    The susceptibility of smoldering to changes in air supply was studied. With a small gap at the bottom of the fuel bed, the increased air flow in the same direction as the initial smoldering front (forward air flow) caused a significantly more intense combustion compared to the normal set-up with opposed air flow.

    Heat extraction from the combustion was studied using a water-cooled copper pipe. Challenges with direct fuel-water contact (fuel swelling, water channeling and runoff) were thus avoided. Smoldering was extinguished in 7 of 15 cases where heat extraction was in the same range as the heat production from combustion. This is the first experimental proof-of-concept of cooling as an extinguishment method for smoldering fires.

    Marginal differences in heating and cooling separated smoldering from extinguished cases; the fuel bed was at a heating-cooling balance point. Lower cooling levels did not lead to extinguishment, but cooling caused more predictable smoldering, possibly delaying the most intense combustion. Also observed at the balance point were pulsating temperatures; a form of long-lived (hours), macroscopic synchronization not previously observed in smoldering fires.

    For practical applications, cooling could be feasible for prevention of temperature escalation from self-heating in industrial storage units. This study provides a first step towards improved fuel storage safety for biomass. 

  • 45.
    Frogner-Kockum, Paul Christian
    et al.
    Swedish Geotechnical Institute, Sweden.
    Lindqvist, Jan Erik
    RISE, SP – Sveriges Tekniska Forskningsinstitut, CBI Betonginstitutet AB, Tillståndsbedömningar.
    Long-term performance of MSWI Bottom ash in a test road construction2016In: International Journal of Sustainable Construction Engineering and Technology, ISSN 2180-3242, Vol. 7, no 1Article in journal (Refereed)
    Abstract [en]

    The study focuses on long-term performances of MSWI bottom ash used as a reinforcement layer in a 8 years old road-construction. Long term properties may change under the combined effects of loading, climate- and chemical conditions. Characterization of the chemical changes in aged MSWI bottom ash is thus of prime interest as secondary alteration is a key process for the ageing of these kind of materials. The MSWI bottom ash in this study comprises a 60 meter-long segment of a test road, which was sampled eight years after construction. The objective of the sampling was to obtain a very low degree of disturbance to the application’s in-situ properties. Access to the sub-base was achieved by removing the surface course and unbound base course, leaving the top surface of the unbound sub-base reachable.  Epoxy impregnated slabs were also used for a micro textural and chemical characterization by SEM/EDS of the bottom ash sub-base layer. No cracks that imply movements or rotation of particles in the road construction or other disturbances as due to the sampling process were found. This undisturbed material made it possible to study chemical processes and structural changes that have been ongoing in the test road since it was constructed. The SEM/EDS analysis showed that most particles had reacted to some extent and that reaction-products surrounding aluminum particles were undisturbed. Partly decomposed particles indicate that the reaction (that has been ongoing since the road was constructed) has been slow and incomplete because of the coexistence of metallic aluminum and aluminum hydroxide. It also shows that the material not has been subjected to any physical influence during these 8 years that otherwise would have moved the reaction products from the particles that originally have reacted. Clay mineralization that indicates long-term ageing of the ash material was also detected by XRPD. The pH of the material was lower than 8.5, indicating a mature degree of carbonization. It is also concluded from the study that chemical reactions consistent with this maturity have been taking place in the road construction as indicated by textural relationships.

  • 46.
    Gallstedt, M
    et al.
    RISE, Innventia.
    Hendeqvist, M S
    Ture, H
    Production, chemistry and properties of proteins2011In: Biopolymers: New Materials for Sustainable Films and Coatings, Wiley , 2011, , p. 27Chapter in book (Refereed)
  • 47.
    Gao, Jiajia
    et al.
    KTH Royal Institue of Technology, Sweden.
    Fischer, Andreas
    KTH Royal Institue of Technology, Sweden.
    Svensson, Per H
    RISE - Research Institutes of Sweden, Bioscience and Materials, Surface, Process and Formulation. KTH Royal Institue of Technology, Sweden.
    Kloo, Lars
    KTH Royal Institue of Technology, Sweden.
    Crystallography as forensic tool for understanding electrolyte degradation in dye-sensitized solar cells2017In: ChemistrySelect, Vol. 2, no 4, p. 1675-1680Article in journal (Refereed)
    Abstract [en]

    The precipitation of solid compounds from model electrolytes for liquid dye-sensitized solar cells has a story to tell regarding decomposition processes to be expected in such systems. Of course, the crystal lattice energy for a specific crystalline compounds plays a role in what compound that will eventually precipitate, but the compounds nevertheless serve as indicators for what type of processes that take place in the solar cell electrolytes upon ageing. From the compounds isolated in this study we learn that both ligand exchange processes, double-salt precipitation and oxidation are degradation processes that should not be overlooked when formulating efficient and stable electrolytes for this type of electrochemical system.

  • 48.
    Gao, Yu
    et al.
    Washington University, USA.
    Walker, Michael J
    Washington University, USA.
    Barrett, Jacob A
    University of California, USA.
    Hosseinaei, Omid
    RISE - Research Institutes of Sweden, Bioeconomy, Biorefinery and Energy.
    Harper, David P
    University of Tennessee, USA.
    Ford, Peter C
    University of California, USA.
    Williams, Brent J
    Washington University, USA.
    Foston, Marcus B
    Washington University, USA.
    Analysis of gas chromatography/mass spectrometry data for catalytic lignin depolymerization using positive matrix factorization2018In: Green Chemistry, ISSN 1463-9262, E-ISSN 1463-9270, Vol. 20, no 18, p. 4366-4377Article in journal (Refereed)
    Abstract [en]

    Various catalytic technologies are being developed to efficiently convert lignin into renewable chemicals. However, due to its complexity, catalytic lignin depolymerization often generates a wide and complex distribution of product compounds. Gas chromatography/mass spectrometry (GC-MS) is a common analytical technique to profile the compounds that comprise lignin depolymerization products. GC-MS is applied not only to determine the product composition, but also to develop an understanding of the catalytic reaction pathways and of the relationships among catalyst structure, reaction conditions, and the resulting compounds generated. Although a very useful tool, the analysis of lignin depolymerization products with GC-MS is limited by the quality and scope of the available mass spectral libraries and the ability to correlate changes in GC-MS chromatograms to changes in lignin structure, catalyst structure, and other reaction conditions. In this study, the GC-MS data of the depolymerization products generated from organosolv hybrid poplar lignin using a copper-doped porous metal oxide catalyst and a methanol/dimethyl carbonate co-solvent was analyzed by applying a factor analysis technique, positive matrix factorization (PMF). Several different solutions for the PMF model were explored. A 13-factor solution sufficiently explains the chemical changes occurring to lignin depolymerization products as a function of lignin, reaction time, catalyst, and solvent. Overall, seven factors were found to represent aromatic compounds, while one factor was defined by aliphatic compounds.

  • 49.
    Garg, Neeraj
    Uppsala University, Sweden.
    Chemoselective Probe Containing a Unique Bioorthogonal Cleavage Site for Investigation of Gut Microbiota Metabolism2018In: Angewandte Chemie, ISSN n2:1433-7851, Vol. 57, no 42, p. 13805-13809Article in journal (Refereed)
  • 50.
    Garg, Neeraj
    Uppsala University, Sweden.
    Highly Sensitive MassSpectrometric Analysis of Metabolic Ketones and Aldehydes in Human FecalSamples2019In: Chemical Communications, ISSN 1359-7345, Vol. 55, no 62, p. 9080-9083Article in journal (Refereed)
12345 1 - 50 of 218
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