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  • 51.
    Chang, Tingru
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap.
    The role of Sn on the long-term atmospheric corrosion of binary Cu-Sn bronze alloys in architectureManuskript (preprint) (Annet vitenskapelig)
  • 52.
    Chang, Tingru
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap.
    Herting, Gunilla
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap.
    Goidanich, S.
    Sánchez Amaya, J. M.
    Arenas, M. A.
    Le Bozec, N.
    Jin, Y.
    Leygraf, Christopher
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap.
    Odnevall Wallinder, Inger
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap.
    The role of Sn on the long-term atmospheric corrosion of binary Cu-Sn bronze alloys in architecture2019Inngår i: Corrosion Science, ISSN 0010-938X, E-ISSN 1879-0496, Vol. 149, s. 54-67Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The role of Sn on the atmospheric corrosion performance of binary Cu-Sn bronze alloys (4–6 wt.% Sn) compared with Cu metal used in outdoor architecture is elucidated in terms of microstructure, native surface oxide composition, patina evolution, corrosion rates, appearance and metal release. Results are presented for non-exposed surfaces and surfaces exposed at different urban and marine sites in Europe up to 5 years and based on multi-analytical findings from microscopic, spectroscopic, electrochemical and chemical investigations. Alloying influenced the corrosion, aesthetic appearance and patina evolution, differently for urban and marine sites, whereas no effects were observed on the release pattern.

  • 53.
    Chang, Tingru
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap.
    Leygraf, Christopher
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Odnevall Wallinder, Inger
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Jin, Ying
    Univ Sci & Technol Beijing, Natl Ctr Mat Serv Safety, Beijing 100083, Peoples R China..
    Understanding the Barrier Layer Formed via Adding BTAH in Copper Film Electrodeposition2019Inngår i: Journal of the Electrochemical Society, ISSN 0013-4651, E-ISSN 1945-7111, Vol. 166, nr 2, s. D10-D20Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The influence of surface adsorption of benzotriazole (BTAH) and of chloride ions (Cl-) on the kinetics of copper electrodeposition/dissolution in copper sulfate solutions and on copper deposit characteristics have been investigated using electrochemical quartz crystal microbalance (EQCM) combined with cyclic voltammetry (CV). The addition of BTAH alone increases the overpotential of copper deposition, whereas a Cu(I)BTA complex forms at potentials higher than 0.08 V (vs. SCE) accompanied with the occurrence of copper anodic dissolution. With simultaneous addition of BTAH and Cl-, surface adsorption of Cl- competes with that of BTAH during the initial stage of copper nucleation. Different cuprous reaction intermediates form in the examined potential range -0.4 to 0.3 V (vs. SCE), which partly eliminate the favorable effect of BTAH on the deposited copper. A BTAH-containing adsorbed layer formed on the matte side of electrodeposited copper film in the presence of BTAH with or without Cl-, exhibiting a barrier surface property and an improved corrosion resistance compared with the copper film electrodeposited in the electrolyte without addition of BTAH.

  • 54.
    Chang, Tingru
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap. University of Science and Technology Beijing, China.
    Wallinder, Inger Odnevall
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap.
    Jin, Ying
    Leygraf, Christofer
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap.
    The golden alloy Cu-5Zn-5Al-1Sn: A multi-analytical surface characterization2018Inngår i: Corrosion Science, ISSN 0010-938X, E-ISSN 1879-0496, Vol. 131, s. 94-103Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The golden alloy Cu-5Zn-5Al-1Sn has found many applications because of its appearance and resistance to tarnishing. The microstructure and multi-component surface oxide of Cu-5Zn-5Al-1Sn have been investigated through a multi-analytical approach. Compared to commercial Cu metal, Cu-5Zn-5Al-1Sn has significantly smaller grains and higher fraction of coherent twin boundaries. The 5-10 nm thick oxide formed after diamond polishing has four identified sub-oxides all contributing to the overall corrosion resistance. Cu2O is mainly located in the outer part, followed by ZnO, SnO2 and Al2O3 closer to the alloy substrate. The latter three possess barrier properties, while Cu2O exhibits a more complex structure.

  • 55.
    Chaudhary, Himanshu
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi.
    Ferreira Fernandes, Ricardo M.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi. Centro de Investigação em Química, Department of Chemistry and Biochemistry, Faculty of Science, University of Porto, Rua do Campo Alegre, s/n, Porto, P-4169-007, Portugal.
    Gowda, Vasantha
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi.
    Claessens, Mirelle M. A. E.
    Furo, Istvan
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi.
    Lendel, Christofer
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi.
    Intrinsically disordered protein as carbon nanotube dispersant: How dynamic interactions lead to excellent colloidal stability2019Inngår i: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 556, s. 172-179Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The rich pool of protein conformations combined with the dimensions and properties of carbon nanotubes create new possibilities in functional materials and nanomedicine. Here, the intrinsically disordered protein α-synuclein is explored as a dispersant of single-walled carbon nanotubes (SWNTs) in water. We use a range of spectroscopic methods to quantify the amount of dispersed SWNT and to elucidate the binding mode of α-synuclein to SWNT. The dispersion ability of α-synuclein is good even with mild sonication and the obtained dispersion is very stable over time. The whole polypeptide chain is involved in the interaction accompanied by a fraction of the chain changing into a helical structure upon binding. Similar to other dispersants, we observe that only a small fraction (15–20%) of α-synuclein is adsorbed on the SWNT surface with an average residence time below 10 ms

  • 56. Chen, C.
    et al.
    Cheng, M.
    Li, H.
    Qiao, F.
    Liu, Peng
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Kloo, Lars
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Sun, Licheng
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Molecular engineering of ionic type perylenediimide dimer-based electron transport materials for efficient planar perovskite solar cells2018Inngår i: Materials Today Energy, ISSN 2468-6069, Vol. 9, s. 264-270Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The main of this work is to overcome the drawbacks of the traditional fullerene derivatives used as electron transport materials (ETMs) for perovskite solar cells (PSCs). Herein, a new strategy to design non-fullerene ETMs is presented by molecular engineering to include charged moieties in the ETM. The designed ETM FA2+-PDI2 is intrinsically ionic and the incorporated counter ions in FA2+-PDI2 significantly increase the electron conductivity and improve the film formation properties. Through careful device optimization, PSCs based on the ionic ETM FA2+-PDI2 exhibit an impressive average power conversion efficiency (PCE) of 17.0%, which is comparable to the PSC based on PC61BM (17.5%). The superior photovoltaic performance can be attributed to efficient electron extraction and effective electron transfer in the PSCs. This work provides important insights regarding the future design of new and efficient non-fullerene ETMs for PSCs. 

  • 57.
    Chen, Cheng
    et al.
    Jiangsu Univ, Inst Energy Res, Zhenjiang 212013, Peoples R China..
    Li, Hongping
    Jiangsu Univ, Inst Energy Res, Zhenjiang 212013, Peoples R China..
    Ding, Xingdong
    Jiangsu Univ, Inst Energy Res, Zhenjiang 212013, Peoples R China..
    Cheng, Ming
    Jiangsu Univ, Inst Energy Res, Zhenjiang 212013, Peoples R China..
    Li, Henan
    Jiangsu Univ, Sch Chem & Chem Engn, Zhenjiang 212013, Peoples R China..
    Xu, Li
    Jiangsu Univ, Inst Energy Res, Zhenjiang 212013, Peoples R China..
    Qiao, Fen
    Jiangsu Univ, Sch Energy & Power Engn, Zhenjiang 212013, Peoples R China..
    Li, Huaming
    Jiangsu Univ, Inst Energy Res, Zhenjiang 212013, Peoples R China..
    Sun, Licheng
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Molecular Engineering of Triphenylamine-Based Non-Fullerene Electron-Transport Materials for Efficient Rigid and Flexible Perovskite Solar Cells2018Inngår i: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 10, nr 45, s. 38970-38977Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    There has been a growing interest in the design and synthesis of non-fullerene electron transport materials (ETMs) for perovskite solar cells (PSCs), which may overcome the drawbacks of traditional fullerene derivatives. In this work, a novel donor-acceptor (D-A) structured ETM termed TPA-3CN is presented by molecular engineering of triphenylamine (TPA) as the donor group and (3-cyano-4,5,5-trimethyl-2(5H)-furanylidene) malononitrile as the acceptor group. To further improve the electron mobility and conductivity and achieve excellent photovoltaic performance, a solution processable n-type dopant is introduced during the ETM spin-coating step. After device optimization, PSCs based on the doped TPA-3CN exhibit an impressive power conversion efficiency (PCE) of 19.2% with a negligible hysteresis. Benefitting from the low temperature and good solution processability of ETM TPA-3CN, it was further applied in flexible inverted PSCs and an impressive PCE of 13.2% was achieved, which is among the highest values reported for inverted flexible fullerene-free PSCs.

  • 58. Chen, H.
    et al.
    Gao, Y.
    Ye, L.
    Yao, Y.
    Chen, X.
    Wei, Y.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    A Cu2Se-Cu2O film electrodeposited on titanium foil as a highly active and stable electrocatalyst for the oxygen evolution reaction2018Inngår i: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, Vol. 54, nr 39, s. 4979-4982Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Many nonprecious metal-selenide-based materials have been reported as electrocatalysts with high activity for the oxygen evolution reaction (OER). Herein, a hybrid catalyst film composed of Cu2Se and Cu2O nanoparticles directly grown on Ti foil (Cu2Se-Cu2O/TF) was prepared through a simple and fast cathodic electrodeposition method. Surprisingly, this electrode required a relatively low overpotential of 465 mV to achieve a catalytic current density of 10 mA cm-2 for the OER in 0.2 M carbonate buffer (pH = 11.0). Furthermore, a long-term constant current electrolysis test confirmed the high durability of the Cu2Se-Cu2O/TF anode at a current density of 10 mA cm-2 over 20 h. The XRD, TEM and XPS analysis of the sample after the OER indicated that a CuO protective layer formed on the surface of the Cu2Se-Cu2O catalyst, which effectively suppressed further oxidation of the Cu2Se-Cu2O catalyst during the OER and resulted in sustained catalytic oxidation of water.

  • 59.
    Chen, Pan
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Terenzi, Camilla
    Wageningen Univ & Res, Wageningen, Netherlands..
    Furo, Istvan
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Berglund, Lars
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Wohlert, Jakob
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Heterogeneous dynamics in cellulose from molecular dynamics simulations2019Inngår i: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 257Artikkel i tidsskrift (Annet vitenskapelig)
  • 60.
    Chen, Song
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Abdel-Magied, Ahmed F.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Fu, Le
    Uppsala Universitet, Department of Engineering Sciences.
    Jonsson, Mats
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Incorporation of strontium and europium in crystals of α-calcium isosaccharinate2019Inngår i: Journal of Hazardous Materials, ISSN 0304-3894, E-ISSN 1873-3336, Vol. 364, s. 309-316Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The final repository for short-lived, low and intermediate level radioactive waste in Sweden is built to act as a passive repository. Already within a few years after closure water will penetrate the repository and conditions of high alkalinity (pH 10.5―13.5) and low temperature (< 7 °C) will prevail. The mobility of radionuclides in the repository is dependent on the radionuclides distribution between solid and liquid phases. In the present work the incorporation of strontium (II) and europium (III) in α-calcium isosaccharinate (ISA) under alkaline conditions (pH ~10) at 5 °C and 50 °C have been studied. The results show that strontium and europium are incorporated into α-Ca(ISA)2 when crystallized both at 5 °C and 50 °C. Europium is incorporated to a greater extent than strontium. The highest incorporation of europium and strontium at 5 °C rendered the phase compositions Ca0.986Eu0.014(ISA)2 (2.4% of Eu(ISA)3 by mass) and Ca0.98Sr0.02(ISA)2 (2.2% of Sr(ISA)2 by mass). XPS spectra show that both trivalent and divalent Eu coexist in the Eu incorporated samples. Strontium ions were found to retard the elongated growth of the Ca(ISA)2crystals. The incorporation of Sr2+ and Eu3+ into the solid phase of Ca(ISA)2 is expected to contribute to a decreased mobility of these ions in the repository.

  • 61.
    Chen, Sulin
    et al.
    Shanghai Jiao Tong Univ, Sch Mech Engn, Shanghai 200240, Peoples R China..
    Shen, Bin
    Shanghai Jiao Tong Univ, Sch Mech Engn, Shanghai 200240, Peoples R China..
    Zhang, Fan
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap.
    Hong, Hong
    Shanghai Jiao Tong Univ, Sch Mech Engn, Shanghai 200240, Peoples R China..
    Pan, Jinshan
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap.
    Mussel-Inspired Graphene Film with Enhanced Durability as a Macroscale Solid Lubricant2019Inngår i: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 11, nr 34, s. 31386-31392Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Graphene has exhibited massive potential as a macroscale solid lubricant, but its durability is limited due to the weak adhesion between graphene sheets and the substrate. Here, inspired by mussel adhesive protein (MAP), effective reinforcement of the graphene-substrate interaction to attain remarkable enhancement on the durability of the graphene film is presented. The mussel-inspired graphene (mGr) film exhibits a coefficient of friction stabilizing at 0.16 up to 490000 sliding cycles in the friction testing against the silicon nitride ball; in the identical sliding condition, comparatively, the graphene (Gr) film without MAP only lasts 4300 sliding cycles. The analysis of Raman and ATR-FTIR demonstrates that, on the one hand, the MAP film firmly adsorbs onto the substrate via forming metal-catechol coordination bonds with metal atoms; on the other hand, it establishes strong interactions with graphene sheets by hydrogen bonding as well as the pi-pi overlap. As an interlayer, MAP retains graphene sheets within the contact interface in the form of a compact tribo-layer, which results in an over 2 orders of magnitude enhancement of durability for the mGr film. This strategy of improving the graphene-substrate adhesion via MAP offers an avenue for the development of effective and reliable graphene-based solid lubricants for engineering applications.

  • 62.
    Cheng, Jie
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap. Tsinghua University, Beijing, China.
    Pan, J.
    Wang, T.
    Lu, X.
    Micro-galvanic corrosion of Cu/Ru couple in potassium periodate (KIO4) solution2018Inngår i: Corrosion Science, ISSN 0010-938X, E-ISSN 1879-0496, Vol. 137, s. 184-193Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This paper focuses on the study of micro-galvanic corrosion of the Cu/Ru couple in KIO4 solution. Practical nobility across the Cu/Ru interface was evaluated by Volta potential mapping, and the morphological changes were monitored by in-situ atomic force microscopy measurements during exposure in a KIO4 solution. Chemical composition of precipitated corrosion product was analyzed by Confocal Raman spectroscopy immediately after the exposure. The results show that Cu is the anode of the Cu/Ru couple, and accelerated dissolution of Cu preferentially occurs near the Cu/Ru interface. However, subsequent formation of insoluble Cu(IO3)2·nH2O leads to precipitation, which impedes further Cu corrosion.

  • 63.
    Chernyshev, Alexander
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Jonsson, Mats
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Impact of organic cement additives on the mobility of radionuclides in a radioactive waste repository2017Konferansepaper (Fagfellevurdert)
  • 64.
    Chernyshev, Alexander N.
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Jonsson, Mats
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Forsberg, Kerstin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Resursåtervinning.
    Characterization and degradation of a polyaryl ether based superplasticizer for use in concrete barriers in deep geological repositories2018Inngår i: Applied Geochemistry, ISSN 0883-2927, E-ISSN 1872-9134, Vol. 95, s. 172-181Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Superplasticizers are important additives used in concrete barriers in geological waste repositories. Superplasticizers have been a major concern in the long-term assessments of safe geological disposal for radioactive waste since superplasticizers and their degradation products can act as complexing ligands and thereby increase the mobility of radionuclides. In this work a new type of superplasticizer, based on a polyaryl ether polymer, has been characterized. It was found that the superplasticizer combines the structural features of polycarboxylate ether based superplasticizers and sulfonated naphthalene-formaldehyde based superplasticizers and that it contains organophosphatecharged groups. A novel method for evaluating the rate of degradation of the superplasticizer under alkaline conditions was elaborated and the degradation products and rate constant of the process was determined. The results demonstrate that degradation occurs rapidly compared to the typical lifetime of a repository.

  • 65.
    Cifelli, M.
    et al.
    Univ Pisa, Dipartimento Chim & Chim Ind, I-56124 Pisa, Italy..
    Domenici, V.
    Univ Pisa, Dipartimento Chim & Chim Ind, I-56124 Pisa, Italy..
    Chizhik, V. I.
    St Petersburg State Univ, Dept Phys, St Petersburg 199034, Russia..
    Dvinskikh, Sergey
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi. St Petersburg State Univ, Lab Biomol NMR, St Petersburg 199034, Russia.
    N-15-C-13 Dipole Couplings in Smectic Mesophase of a Thermotropic Ionic Liquid2018Inngår i: Applied Magnetic Resonance, ISSN 0937-9347, E-ISSN 1613-7507, Vol. 49, nr 6, s. 553-562Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Unique combination of ionic conductivity and anisotropic physical properties in ionic liquid crystals leads to new dynamic properties exploited in modern technological applications. Structural and dynamics information at atomic level for molecules and ions in mesophases can be obtained by nuclear magnetic resonance (NMR) spectroscopy through the measurements of dipole-dipole spin couplings. While C-13-H-1 and N-15-H-1 dipolar NMR spectra can be routinely acquired in samples with natural isotopic abundance, recording N-15-C-13 dipolar NMR spectra is challenging because of the unfavourable combination of two rare isotopes. In the present study, an approach to measure N-15-C-13 dipole-dipole NMR spectra in static liquid crystalline samples with natural abundance is introduced. We demonstrate that well-resolved spectra can be recorded within 10 h of experimental time using a conventional NMR probe and a moderately strong magnetic field. The technique is applied to a thermotropic smectic mesophase formed by an ionic liquid with imidazolium-based organic cation.

  • 66.
    Claesson, Per M.
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap. RISE.
    Dobryden, Illia
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap.
    He, Yunjuan
    KTH, Skolan för industriell teknik och management (ITM), Energiteknik, Kraft- och värmeteknologi.
    Li, Gen
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap.
    Surface Nanomechanics of Coatings and Hydrogels2019Inngår i: IOP Conference Series: Materials Science and Engineering, Institute of Physics Publishing , 2019, nr 1Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Due to the increasing use of nanostructured materials and thin coatings as barrier materials, it has become of high importance to measure and understand material properties on the nm to 100 nm length scales. In this article we demonstrate and discuss how atomic force microscopy techniques can be used to this end. It is demonstrated that the classical analysis based on the assumption of a purely elastic material response is a fair approximation for relatively stiff coatings (elastic modulus order of GPa), whereas viscous responses must be considered for soft materials (apparent modulus order of MPa) such as hydrogels.

  • 67.
    Cuartero, Maria
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi.
    Chai, Lijun
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi.
    Zhang, Biaobiao
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Organisk kemi.
    De Marco, Roland
    Univ Sunshine Coast, Fac Sci Hlth Educ & Engn, 90s Sippy Downs Dr, Sippy Downs, Qld 4556, Australia.;Univ Queensland, Sch Chem & Mol Biosci, Brisbane, Qld 4072, Australia.;Curtin Univ, Fuels & Energy Technol Inst, Perth, WA 6102, Australia..
    Crespo, Gaston A.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi.
    Ferrocene self assembled monolayer as a redox mediator for triggering ion transfer across nanometer-sized membranes2019Inngår i: Electrochimica Acta, ISSN 0013-4686, E-ISSN 1873-3859, Vol. 315, s. 84-93Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Modulation of ion-transfer processes across nanometer-sized voltammetry membranes by ferrocene-based self-assembled monolayer on regular glassy carbon electrode is herein demonstrated. The composition of the membrane is advantageously tuned to promote either cation or anion transfer: the presence of an exchangeable cation results in cation transfer, whereas a lipophilic salt induces anion transfer through the fulfilment of the electroneutrality of the system. When an anodic scan oxidizes ferrocene moieties in the monolayer, these are stabilized by the pairing of lipophilic anions present in the membrane. As a result, either, hydrophilic cations present in the membrane are expelled into the solution or anions enter from the solution generating hence reversible and voltammetric waves for these transfers. The use of a redox active monolayer rather than a conducting polymer film or a redox active compound into the membrane overcomes a number of drawbacks previously manifested by these systems. The confinement of the redox process in a thin film at the immediate vicinity of the membrane allows to avoid the need of elevated number of redox moieties to be sued in the membrane, therefore suppressing its acute leaching and being compatible with the incorporation of both cation and anion ionophores for the first time. In this sense, assisted transfer of lithium and chloride are shown as proof-of-concept. Here, the peak potential of the associated voltammetric waves shifts according to the Nernst equation, in analogy to potentiometric sensors. Analytical detection of lithium and chloride ions in real samples is additionally presented.

  • 68.
    Cuartero, Maria
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi.
    Crespo, Gaston A.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi.
    All-solid-state potentiometric sensors: A new wave for in situ aquatic research2018Inngår i: Current Opinion in Electrochemistry, ISSN 2451-9103, Vol. 10, s. 98-106Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Over the last few years, all-solid-state potentiometric ion-selective sensors have demonstrated a huge potential for environmental water analysis. Beyond the excellent analytical performances exhibited in benchtop conditions for the detection of important targets (e.g. pH, species relevant to the carbon and nitrogen cycles, trace metals), the challenge now lies in bringing those sensors to in situ format and obtaining valuable chemical information directly in the field while minimizing or avoiding the need for sampling. Technically speaking, the instrumentation for potentiometric assessment is extremely simple, low cost and requires minimal space. In addition, the all-solid-state configuration seems ideal to fabricate miniaturized sensors with sufficient analytical performance to detect certain ions in water resources. Herein, we highlight the power of all-solid-state potentiometric sensors applied to environmental water analysis providing a threefold overview: (i) the recent materials used in the fabrication of all-solid-state polymeric membrane electrodes, both the solid contact and ion-selective membrane; (ii) a collection of the main targets explored during the last 5 years; and (iii) examples of the most recent and relevant in situ applications employing submersible equipment. Throughout the review, issues such as ‘What are the real implications of all-solid-state membrane electrodes in the environmental field?’ and ‘To what extent has the effort in developing new sensors over time been well-exploited?’ are addressed. Convincingly, all-solid-state potentiometric sensors are positioning as a unique in situ interface providing real-time data that allow for an understanding of ongoing biogeochemical processes and possible anthropogenic activities implications.

  • 69.
    Cuartero, Maria
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi.
    Crespo, Gaston A.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi.
    Using Potentiometric Electrodes Based on Nonselective Polymeric Membranes as Potential Universal Detectors for Ion Chromatography: Investigating an Original Research Problem from an Inquiry-Based-Learning Perspective2018Inngår i: Journal of Chemical Education, ISSN 0021-9584, E-ISSN 1938-1328, Vol. 95, nr 12, s. 2172-2181Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Because traditional laboratory practices in advanced chemistry education are being replaced by inquiry based approaches, we present herein a new laboratory activity based on a small research project that was designed and executed by students. The laboratory project aims at answering a well-defined research question: how far can potentiometric electrodes based on nonselective polymeric membranes be used as universal detectors in ion chromatography (IC)? Hence, the experiments were designed and conducted to explore the analytical performances of potentiometric electrodes based on different commercial membranes that are typically used in electrodialysis. The nonselective behavior shown by the electrodes permits a critical evaluation of their further implementation as a universal detector of anions in regular IC. Thus, the students were able to integrate a nonselective potentiometric sensor to analyze several anions in flow mode, mimicking the signal that is to be obtained using such electrodes as an IC detector. The proposed practice covers different pedagogical purposes: (i) to develop competence toward "thinking like a scientist" through reflective teaching; (ii) to promote argumentation skills and critical decision making; (iii) to improve students' research-planning and experimental-design skills; (iv) to refresh conceptual knowledge about analytical detectors, which typically goes unnoticed in laboratory practices; and (v) to reinforce students' knowledge about the basis of potentiometry. Furthermore, the present document may serve as an easy guide to develop other laboratory practices based on potentiometric sensors.

  • 70.
    Cánovas, Rocío
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Cuartero, Maria
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Crespo, Gaston A.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Modern creatinine (Bio)sensing: Challenges of point-of-care platforms2019Inngår i: Biosensors & bioelectronics, ISSN 0956-5663, E-ISSN 1873-4235, Vol. 130, s. 110-124Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    The importance of knowing creatinine levels in the human body is related to the possible association with renal, muscular and thyroid dysfunction. Thus, the accurate detection of creatinine may indirectly provide information surrounding those functional processes, therefore contributing to the management of the health status of the individual and early diagnosis of acute diseases. The questions at this point are: to what extent is creatinine information clinically relevant?; and do modern creatinine (bio)sensing strategies fulfil the real needs of healthcare applications? The present review addresses these questions by means of a deep analysis of the creatinine sensors reported in the literature over the last five years. There is a wide range of techniques for detecting creatinine, most of them based on optical readouts (20 of the 33 papers collected in this review). However, the use of electrochemical techniques (13 of the 33 papers) is recently emerging in alignment with the search for a definitive and trustworthy creatinine detection at the point-of-care level. In this sense, biosensors (7 of the 33 papers) are being established as the most promising alternative over the years. While creatinine levels in the blood seem to provide better information about patient status, none of the reported sensors display adequate selectivity in such a complex matrix. In contrast, the analysis of other types of biological samples (e.g., saliva and urine) seems to be more viable in terms of simplicity, cross-selectivity and (bio)fouling, besides the fact that its extraction does not disturb individual's well-being. Consequently, simple tests may likely be used for the initial check of the individual in routine analysis, and then, more accurate blood detection of creatinine could be necessary to provide a more genuine diagnosis and/or support the corresponding decision-making by the physician. Herein, we provide a critical discussion of the advantages of current methods of (bio)sensing of creatinine, as well as an overview of the drawbacks that impede their definitive point-of-care establishment.

  • 71.
    Dahlgren, Björn
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Dispenza, Clelia
    Jonsson, Mats
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi.
    Numerical Simulation of the Kinetics of Radical Decay in Single-Pulse High-Energy Electron-Irradiated Polymer Aqueous Solutions2019Inngår i: Journal of Physical Chemistry A, ISSN 1089-5639, E-ISSN 1520-5215, Vol. 123, nr 24, s. 5043-5050Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A new method for the numerical simulation of the radiation chemistry of aqueous polymer solutions is introduced. The method makes use of a deterministic approach combining the conventional homogeneous radiation chemistry of water with the chemistry of polymer radicals and other macromolecular species. The method is applied on single-pulse irradiations of aqueous polymer solutions. The speciation of macromolecular species accounts for the variations in the number of alkyl radicals per chain, molecular weight, and number of internal loops (as a consequence of an intramolecular radical-radical combination). In the simulations, the initial polymer molecular weight, polymer concentration, and dose per pulse (function of pulse length and dose rate during the pulse) were systematically varied. In total, 54 different conditions were simulated. The results are well in line with the available experimental data for similar systems. At a low polymer concentration and a high dose per pulse, the kinetics of radical decay is quite complex for the competition between intra- and intermolecular radical-radical reactions, whereas at a low dose per pulse the kinetics is purely second-order. The simulations demonstrate the limitations of the polymer in scavenging all the radicals generated by water radiolysis when irradiated at a low polymer concentration and a high dose per pulse. They also show that the radical decay of lower-molecular-weight chains is faster and to a larger extent dominated by intermolecular radical-radical reactions, thus explaining the mechanism behind the experimentally observed narrowing of molecular weight distributions.

  • 72.
    Dai, Jing
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi.
    Ferreira Fernandes, Ricardo Manuel
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi. Univ Porto, CIQUP, Dept Chem & Biochem, Fac Sci, P-4169007 Porto, Portugal..
    Regev, Oren
    Ben Gurion Univ Negev, Dept Chem Engn, IL-84105 Beer Sheva, Israel.;Ben Gurion Univ Negev, Ilse Katz Inst Nanotechnol, IL-84105 Beer Sheva, Israel..
    Marques, Eduardo F.
    Univ Porto, CIQUP, Dept Chem & Biochem, Fac Sci, P-4169007 Porto, Portugal..
    Furo, Istvan
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi.
    Dispersing Carbon Nanotubes in Water with Amphiphiles: Dispersant Adsorption, Kinetics, and Bundle Size Distribution as Defining Factors2018Inngår i: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 122, nr 42, s. 24386-24393Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Debundling and dispersing single-walled carbon nanotubes (SWNTs) is essential for applications, but the process is not well understood. In this work, aqueous SWNT dispersions were produced by sonicating pristine SWNT powder in the presence of an amphiphilic triblock copolymer (Pluronic F127) as dispersant. Upon centrifugation, one obtains a supernatant with suspended individual tubes and thin bundles and a precipitate with large bundles (and impurities). In the supernatant, that constitutes the final dispersion, we determined the dispersed SWNT concentration by thermogravi-metric analysis (TGA) and UV-vis spectroscopy, and the dispersant concentration by NMR The fraction of dispersant adsorbed at the SWNT surface was obtained by H-1 diffusion NMR Sigmoidal dispersion curves recording the concentration of dispersed SWNTs as a function of supernatant dispersant concentration were obtained at different SWNT loadings and sonication times. As SWNT bundles are debundled into smaller and smaller ones, the essential role of the dispersant is to sufficiently quickly cover the freshly exposed surfaces created by shear forces induced during sonication. Primarily kinetic reasons are behind the need for dispersant concentrations required to reach a substantial SWNT concentration. Centrifugation sets the size threshold below which SWNT particles are retained in the dispersion and consequently determines the SWNT concentration as a function of sonication time.

  • 73.
    Dai, Jing
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Kharkov, Boris B.
    St Petersburg State Univ, Lab Biomol NMR, St Petersburg 199034, Russia..
    Dvinskikh, Sergey V.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Molecular and Segmental Orientational Order in a Smectic Mesophase of a Thermotropic Ionic Liquid Crystal2019Inngår i: Crystals, ISSN 2073-4352, Vol. 9, nr 1, artikkel-id 18Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We investigate conformational dynamics in the smectic A phase formed by the mesogenic ionic liquid 1-tetradecyl-3-methylimidazolium nitrate. Solid-state high-resolution C-13 nuclear magnetic resonance (NMR) spectra are recorded in the sample with the mesophase director aligned in the magnetic field of the NMR spectrometer. The applied NMR method, proton encoded local field spectroscopy, delivers heteronuclear dipolar couplings of each C-13 spin to its H-1 neighbours. From the analysis of the dipolar couplings, orientational order parameters of the C-H bonds along the hydrocarbon chain were determined. The estimated value of the molecular order parameter S is significantly lower compared to that in smectic phases of conventional non-ionic liquid crystals.

  • 74.
    Daniel, Quentin
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH).
    Duan, Lele
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Timmer, Brian J. J.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH).
    Chen, Hong
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH).
    Luo, Xiaodan
    Peking Univ, Coll Chem & Mol Engn, Beijing 100871, Peoples R China..
    Ambre, Ram
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH).
    Wang, Ying
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH).
    Zhang, Biaobiao
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH).
    Zhang, Peili
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Wang, Lei
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH).
    Li, Fusheng
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Sun, Junliang
    Peking Univ, Coll Chem & Mol Engn, Beijing 100871, Peoples R China..
    Ahlquist, Mårten S. G.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Teoretisk kemi och biologi.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Water Oxidation Initiated by In Situ Dimerization of the Molecular Ru(pdc) Catalyst2018Inngår i: ACS Catalysis, ISSN 2155-5435, E-ISSN 2155-5435, Vol. 8, nr 5, s. 4375-4382Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The mononuclear ruthenium complex [Ru(pdc)L-3] (H(2)pdc = 2,6-pyridinedicarboxylic acid, L = N-heterocycles such as 4-picoline) has previously shown promising catalytic efficiency toward water oxidation, both in homogeneous solutions and anchored on electrode surfaces. However, the detailed water oxidation mechanism catalyzed by this type of complex has remained unclear. In order to deepen understanding of this type of catalyst, in the present study, [Ru(pdc)(py)(3)] (py = pyridine) has been synthesized, and the detailed catalytic mechanism has been studied by electrochemistry, UV-vis, NMR, MS, and X-ray crystallography. Interestingly, it was found that once having reached the Ru-IV state, this complex promptly formed a stable ruthenium dimer [Ru-III(pdc)(py)(2)-O-Ru-IV(pdc)(py)(2)](+). Further investigations suggested that the present dimer, after one pyridine ligand exchange with water to form [Ru-III(pdc)(py)(2)-O-Ru-IV(pdc)(py)(H2O)](+), was the true active species to catalyze water oxidation in homogeneous solutions.

  • 75.
    Danielsson, Marie
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Zhao, Tao
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Organisk kemi. Department of Science and Technology, Örebro University, Örebro, Sweden.
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Organisk kemi.
    Arthropod infestation sites and induced defence can be traced by emission from single spruce needles2019Inngår i: Arthropod-Plant Interactions, ISSN 1872-8855, E-ISSN 1872-8847, Vol. 13, nr 2, s. 253-259Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Emissions of defence chemicals from Norway spruce seedlings can be induced by feeding arthropods or by exogenous hormonal application. Some defence chemicals may attract or repel associated arthropods. The aim of this study was to show that it is possible to detect and collect stress-induced volatiles from micro sites, such as at the scale of a single needle, in vivo by using SPME. Methyl jasmonate application on the stem of Norway spruce seedlings induced emission of (E)-beta-farnesene only from the needles closest to the application site. Emissions of (E)-beta-farnesene, (E,E)-alpha-farnesene and (E)-alpha-bisabolene were only detected from needles infested by the spider mite Oligonychus ununguis. The total volatile amount detected by SPME-GC-MS reached a considerable mass of 14 ng/needle/24 h, suggesting that emission from damaged and stressed conifers might have a larger impact on the macro climate than previously estimated.

  • 76.
    de Jesus, Liana Inara
    et al.
    Univ Fed Parana, Dept Biochem & Mol Biol, CP 19046, Curitiba, PR, Brazil..
    Smiderle, Fhernanda R.
    Univ Fed Parana, Dept Biochem & Mol Biol, CP 19046, Curitiba, PR, Brazil..
    Ruthes, Andrea C.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Vilaplana, Francisco
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Dal'Lin, Fernando Tonholi
    Univ Fed Parana, Dept Pharmacol, CP 19046, Curitiba, PR, Brazil..
    Maria-Ferreira, Daniele
    Univ Fed Parana, Dept Biochem & Mol Biol, CP 19046, Curitiba, PR, Brazil.;Univ Fed Parana, Dept Pharmacol, CP 19046, Curitiba, PR, Brazil..
    Werner, Maria Fernanda
    Univ Fed Parana, Dept Pharmacol, CP 19046, Curitiba, PR, Brazil..
    Van Griensven, Leo J. L. D.
    Wageningen Univ & Res, Plant Res Int, Bomsesteeg 1, NL-6708 PD Wageningen, Netherlands..
    Iacomini, Marcello
    Univ Fed Parana, Dept Biochem & Mol Biol, CP 19046, Curitiba, PR, Brazil..
    Chemical characterization and wound healing property of a beta-D-glucan from edible mushroom Piptoporus betulinus2018Inngår i: International Journal of Biological Macromolecules, ISSN 0141-8130, E-ISSN 1879-0003, Vol. 117, s. 1361-1366Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A water-soluble beta-D-glucan was obtained from fruiting bodies of Piptoporus betulinus, by hot aqueous extraction followed by freeze-thawing procedure and dialysis. Its molar mass distribution and conformational behavior in solution was assessed by size-exclusion chromatography coupled with multiangle laser light scattering, showing a polysaccharide with an average molecular weight of 2.5 x 10(5) Da with a random coil conformation for molecular weights below 1 x 10(6) Da. Typical signals of beta-(1 -> 3)-linkages were observed in NMR spectrum (delta 102.7/4.76; 102.8/4.74; 102.9/4.52; and delta 85.1/3.78; 85.0/3.77) and also signals of O-6 substitution at delta 69.2/4.22 and 69.2/3.87. The analysis of partially O-methylated alditol acetates corroborates the NMR results, indicating the presence of a beta-D-glucan with a main chain (1 -> 3)-linked, substituted at O-6 by single-units of glucose. The beta-D-glucan showed no toxicity on human colon carcinoma cell line (Caco-2) up to 1000 mu g mL(-1) and promoted cell migration on in vitro scratch assay, demonstrating a potential wound healing capacity.

  • 77.
    Dedinaite, Andra
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap.
    Claesson, Per M.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap.
    How synergistic aqueous lubrication is mediated by natural and synthetic molecular aggregates2019Inngår i: IOP Conference Series: Materials Science and Engineering, Institute of Physics Publishing , 2019, nr 1Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Nature lubricates in aqueous environment, and thus the example of a human synovial joint with its seamless function has been a fascination for scientists since the times of the birth of modern science. Here, inspired by nature, we investigate the mechanistic function of three different types of synergistic molecular aggregates. Firstly, we show how simple phospholipids lubricate hydrophilic model surfaces of silica and how this lubrication is facilitated further by the presence of an anionic polysaccharide, hyaluronan, due to the enhanced surface build-up of lubricant material. Next, we mimic natural polylectrolytesurfactant aggregation by employing a highly positively charged polyelectrolyte and anionic surfactant that strongly associate both in the bulk and at the surfaces by building structured aggregates that lubricate due to hydration lubrication. This occurs despite of the presence of strong attraction between the lubricated surfaces. This is an example of synergistic lubrication due to particular internal structural arrangement of the aggregates. Finally, we investigate the case of synergistic lubrication due to preferential surface ordering of two biological polyelectrolytes, cartilage oligomeric matrix protein and lubricin, that leads to favourable lubrication.

  • 78.
    Di Bucchianico, Sebastiano
    et al.
    Karolinska Inst, Inst Environm Med, Stockholm, Sweden..
    Gliga, Anda R.
    Karolinska Inst, Inst Environm Med, Stockholm, Sweden..
    Åkerlund, Emma
    Karolinska Inst, Inst Environm Med, Stockholm, Sweden..
    Skoglund, Sara
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap.
    Odnevall Wallinder, Inger
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap.
    Fadeel, Bengt
    Karolinska Inst, Inst Environm Med, Stockholm, Sweden..
    Karlsson, Hanna L.
    Karolinska Inst, Inst Environm Med, Stockholm, Sweden..
    Calcium-dependent cyto- and genotoxicity of nickel metal and nickel oxide nanoparticles in human lung cells2018Inngår i: Particle and Fibre Toxicology, ISSN 1743-8977, E-ISSN 1743-8977, Vol. 15, artikkel-id 32Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: Genotoxicity is an important toxicological endpoint due to the link to diseases such as cancer. Therefore, an increased understanding regarding genotoxicity and underlying mechanisms is needed for assessing the risk with exposure to nanoparticles (NPs). The aim of this study was to perform an in-depth investigation regarding the genotoxicity of well-characterized Ni and NiO NPs in human bronchial epithelial BEAS-2B cells and to discern possible mechanisms. Comparisons were made with NiCl2 in order to elucidate effects of ionic Ni. Methods: BEAS-2B cells were exposed to Ni and NiO NPs, as well as NiCl2, and uptake and cellular dose were investigated by transmission electron microscopy (TEM) and inductively coupled plasma mass spectrometry (ICP-MS). The NPs were characterized in terms of surface composition (X-ray photoelectron spectroscopy), agglomeration (photon cross correlation spectroscopy) and nickel release in cell medium (ICP-MS). Cell death (necrosis/apoptosis) was investigated by Annexin VFITC/PI staining and genotoxicity by cytokinesis-block micronucleus (cytome) assay (OECD 487), chromosomal aberration (OECD 473) and comet assay. The involvement of intracellular reactive oxygen species (ROS) and calcium was explored using the fluorescent probes, DCFH-DA and Fluo-4. Results: NPs were efficiently taken up by the BEAS-2B cells. In contrast, no or minor uptake was observed for ionic Ni from NiCl2. Despite differences in uptake, all exposures (NiO, Ni NPs and NiCl2) caused chromosomal damage. Furthermore, NiO NPs were most potent in causing DNA strand breaks and generating intracellular ROS. An increase in intracellular calcium was observed and modulation of intracellular calcium by using inhibitors and chelators clearly prevented the chromosomal damage. Chelation of iron also protected against induced damage, particularly for NiO and NiCl2. Conclusions: This study has revealed chromosomal damage by Ni and NiO NPs as well as Ni ionic species and provides novel evidence for a calcium-dependent mechanism of cyto- and genotoxicity.

  • 79.
    Dispenza, C.
    et al.
    Univ Palermo, Dipartimento Ingn Chim, Gest, Informat,Meccan, Viale Sci,Edificio 6, I-90128 Palermo, Italy.;Royal Inst Technol KTH, Sch Chem Sci & Engn, S-10044 Stockholm, Sweden..
    Spadaro, G.
    Univ Palermo, Dipartimento Ingn Chim, Gest, Informat,Meccan, Viale Sci,Edificio 6, I-90128 Palermo, Italy..
    Jonsson, Mats
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Erratum to: Radiation Engineering of Multifunctional Nanogels2016Inngår i: TOPICS IN CURRENT CHEMISTRY, ISSN 2365-0869, Vol. 374, nr 5, artikkel-id 72Artikkel i tidsskrift (Fagfellevurdert)
  • 80. Ditta, L. A.
    et al.
    Dahlgren, Björn
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi.
    Sabatino, M. A.
    Dispenza, C.
    Jonsson, Mats
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    The role of molecular oxygen in the formation of radiation-engineered multifunctional nanogels2019Inngår i: European Polymer Journal, ISSN 0014-3057, E-ISSN 1873-1945, Vol. 114, s. 164-175Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Nanogels are very promising biomedical nanodevices. The classic “radiation chemistry-based” approach to synthetize nanogels consists in the irradiation with pulsed electron beams of dilute, N 2 O-saturated, aqueous solutions of water-soluble polymers of the “crosslinking type”. Nanogels with controlled size and properties are produced in a single irradiation step with no recourse to initiators, organic solvents and surfactants. This paper combines experimental syntheses, performed with two e-beam irradiation setups and dose-ranges, starting from poly(N-vinyl pyrrolidone) solutions of various concentrations, both in N 2 O-saturated and air-saturated initial conditions, with the numerical simulations of the radiation chemistry of aqueous solutions of a radical scavanger exposed to the same irradiation conditions used in the experiments. This approach provides a methodology to predict the impact of system and irradiation conditions on the water radiation chemistry, which in turn affect the nanogel features in terms of molecular and physico-chemical properties. In particular, the crucial role of initial and transient concentration of molecular oxygen is revealed. This work also proposes a very simple and effective methodology to quantitatively measure the double bonds formed in the systems from disporportionation and chain scission reactions, competing with inter-/intra-molecular crosslinking.

  • 81.
    Dobryden, Illia
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap.
    Ruiz, Maria Cortes
    CUNY City Coll, Dept Chem Engn, Grove Sch Engn, New York, NY 10031 USA..
    Zhang, Xuwei
    Univ Montreal, Dept Chem, CP 6128 Succursale Ctr Ville, Montreal, PQ H3C 3J7, Canada..
    Dédinaité, Andra
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap. RISE Res Inst Sweden, Div Biosci & Mat, SE-11486 Stockholm, Sweden..
    Wieland, D. C. Florian
    Helmholtz Zentrum Geesthacht, Inst Mat Res, Max Planck Str 1, D-21502 Geesthacht, Germany..
    Winnik, Francoise M.
    Univ Helsinki, Dept Chem, POB 55, FI-00014 Helsinki, Finland.;NIMS, Int Ctr Mat Nanoarchitecton MANA, 1-1 Namiki, Tsukuba, Ibaraki 3050044, Japan..
    Claesson, Per M.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap. RISE Res Inst Sweden, Div Biosci & Mat, SE-11486 Stockholm, Sweden..
    Thermoresponsive Pentablock Copolymer on Silica: Temperature Effects on Adsorption, Surface Forces, and Friction2019Inngår i: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 35, nr 3, s. 653-661Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The adsorption of hydrophilic or amphiphilic multiblock copolymers provides a powerful means to produce well-defined "smart" surfaces, especially if one or several blocks are sensitive to external stimuli. We focus here on an A-B-A-B-A copolymer, where A is a cationic poly((3acrylamido-propyl)-trimethylammonium chloride) (PAMPTMA) block containing 15 (end blocks) or 30 (middle block) repeat units and B is a neutral thermosensitive water-soluble poly(2-isopropyl-2-oxazoline) (PIPOZ) block with 50 repeat units. X-ray reflectivity and quartz crystal microbalance with dissipation monitoring were employed to study the adsorption of PAMPTMA(15)-PAMPTMA(30)-PIPOZ(50)-PAMPTMA(15) on silica surfaces. The latter technique was employed at different temperatures up to 50 degrees C. Surface forces and friction between the two silica surfaces across aqueous pentablock copolymer solutions at different temperatures were determined with the atomic force microscopy colloidal probe force and friction measurements. The cationic pentablock copolymer was found to have a high affinity to the negatively charged silica surface, leading to a thin (2 nm) and rigid adsorbed layer. A steric force was encountered at a separation of around 3 nm from hard wall contact. A capillary condensation of a polymer-rich phase was observed at the cloud point of the solution. The friction forces were evaluated using Amontons' rule modified with an adhesion term.

  • 82.
    Dong, Yiran
    et al.
    Univ Illinois, Carl R Woese Inst Genom Biol, 1206 W Gregory Dr, Urbana, IL 61801 USA.;China Univ Geosci, Sch Environm Studies, Wuhan, Hubei, Peoples R China..
    Sanford, Robert A.
    Univ Illinois, Carl R Woese Inst Genom Biol, 1206 W Gregory Dr, Urbana, IL 61801 USA.;Univ Illinois, Dept Geol, Urbana, IL USA..
    Inskeep, William P.
    Montana State Univ, Dept Land Resources & Environm Sci, Bozeman, MT 59717 USA.;Montana State Univ, Thermal Biol Inst, Bozeman, MT 59717 USA..
    Srivastava, Vaibhav
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap.
    Bulone, Vincent
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap. Univ Adelaide, Div Sch Agr Food & Wine, Adelaide, SA, Australia..
    Fields, Christopher J.
    Univ Illinois, Roy J Carver Biotechnol Ctr, Urbana, IL USA..
    Yau, Peter M.
    Univ Illinois, Roy J Carver Biotechnol Ctr, Urbana, IL USA..
    Sivaguru, Mayandi
    Univ Illinois, Carl R Woese Inst Genom Biol, 1206 W Gregory Dr, Urbana, IL 61801 USA.;Univ Illinois, Carl R Woese Inst Genom Biol, Carl Zeiss Labs Locat Partner, Urbana, IL USA..
    Ahren, Dag
    Lund Univ, Dept Biol, Microbial Ecol Grp, Bioinformat Infrastruct Life Sci, Lund, Sweden.;Lund Univ, Pufendorf Inst Adv Sci, Lund, Sweden..
    Fouke, Kyle W.
    Univ Illinois, Carl R Woese Inst Genom Biol, 1206 W Gregory Dr, Urbana, IL 61801 USA..
    Weber, Joseph
    Univ Illinois, Carl R Woese Inst Genom Biol, 1206 W Gregory Dr, Urbana, IL 61801 USA..
    Werth, Charles R.
    Univ Illinois, Carl R Woese Inst Genom Biol, 1206 W Gregory Dr, Urbana, IL 61801 USA.;Univ Texas Austin, Dept Civil Architectural & Environm Engn, Austin, TX 78712 USA..
    Cann, Isaac K.
    Univ Illinois, Carl R Woese Inst Genom Biol, 1206 W Gregory Dr, Urbana, IL 61801 USA.;Univ Illinois, Dept Anim Sci, Urbana, IL USA.;Univ Illinois, Dept Microbiol, Urbana, IL USA..
    Keating, Kathleen M.
    Univ Illinois, Roy J Carver Biotechnol Ctr, Urbana, IL USA..
    Khetani, Radhika S.
    Univ Illinois, Roy J Carver Biotechnol Ctr, Urbana, IL USA..
    Hernandez, Alvaro G.
    Univ Illinois, Roy J Carver Biotechnol Ctr, Urbana, IL USA..
    Wright, Chris
    Univ Illinois, Roy J Carver Biotechnol Ctr, Urbana, IL USA..
    Band, Mark
    Univ Illinois, Roy J Carver Biotechnol Ctr, Urbana, IL USA..
    Imai, Brian S.
    Univ Illinois, Roy J Carver Biotechnol Ctr, Urbana, IL USA..
    Fried, Glenn A.
    Univ Illinois, Carl R Woese Inst Genom Biol, 1206 W Gregory Dr, Urbana, IL 61801 USA.;Univ Illinois, Carl R Woese Inst Genom Biol, Carl Zeiss Labs Locat Partner, Urbana, IL USA..
    Fouke, Bruce W.
    Univ Illinois, Carl R Woese Inst Genom Biol, 1206 W Gregory Dr, Urbana, IL 61801 USA.;Univ Illinois, Dept Geol, Urbana, IL USA.;Montana State Univ, Thermal Biol Inst, Bozeman, MT 59717 USA.;Univ Illinois, Roy J Carver Biotechnol Ctr, Urbana, IL USA.;Univ Illinois, Carl R Woese Inst Genom Biol, Carl Zeiss Labs Locat Partner, Urbana, IL USA.;Lund Univ, Pufendorf Inst Adv Sci, Lund, Sweden.;Bucknell Univ, Dept Geol & Environm Sci, Lewisburg, PA 17837 USA..
    Physiology, Metabolism, and Fossilization of Hot-Spring Filamentous Microbial Mats2019Inngår i: Astrobiology, ISSN 1531-1074, E-ISSN 1557-8070Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The evolutionarily ancient Aquificales bacterium Sulfurihydrogenibium spp. dominates filamentous microbial mat communities in shallow, fast-flowing, and dysoxic hot-spring drainage systems around the world. In the present study, field observations of these fettuccini-like microbial mats at Mammoth Hot Springs in Yellowstone National Park are integrated with geology, geochemistry, hydrology, microscopy, and multi-omic molecular biology analyses. Strategic sampling of living filamentous mats along with the hot-spring CaCO3 (travertine) in which they are actively being entombed and fossilized has permitted the first direct linkage of Sulfurihydrogenibium spp. physiology and metabolism with the formation of distinct travertine streamer microbial biomarkers. Results indicate that, during chemoautotrophy and CO2 carbon fixation, the 87-98% Sulfurihydrogenibium-dominated mats utilize chaperons to facilitate enzyme stability and function. High-abundance transcripts and proteins for type IV pili and extracellular polymeric substances (EPSs) are consistent with their strong mucus-rich filaments tens of centimeters long that withstand hydrodynamic shear as they become encrusted by more than 5mm of travertine per day. Their primary energy source is the oxidation of reduced sulfur (e.g., sulfide, sulfur, or thiosulfate) and the simultaneous uptake of extremely low concentrations of dissolved O-2 facilitated by bd-type cytochromes. The formation of elevated travertine ridges permits the Sulfurihydrogenibium-dominated mats to create a shallow platform from which to access low levels of dissolved oxygen at the virtual exclusion of other microorganisms. These ridged travertine streamer microbial biomarkers are well preserved and create a robust fossil record of microbial physiological and metabolic activities in modern and ancient hot-spring ecosystems.

  • 83.
    Du, Jian
    et al.
    Dalian Univ Technol, State Key Lab Fine Chem, DUT KTH Joint Educ & Res Ctr Mol Devices, Dalian 116024, Peoples R China..
    Li, Fei
    Dalian Univ Technol, State Key Lab Fine Chem, DUT KTH Joint Educ & Res Ctr Mol Devices, Dalian 116024, Peoples R China..
    Wang, Yong
    Dalian Univ Technol, State Key Lab Fine Chem, DUT KTH Joint Educ & Res Ctr Mol Devices, Dalian 116024, Peoples R China..
    Zhu, Yong
    Dalian Univ Technol, State Key Lab Fine Chem, DUT KTH Joint Educ & Res Ctr Mol Devices, Dalian 116024, Peoples R China..
    Sun, Licheng
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Organisk kemi. Dalian Univ Technol, State Key Lab Fine Chem, DUT KTH Joint Educ & Res Ctr Mol Devices, Dalian 116024, Peoples R China..
    Cu3P/CuO Core-Shell Nanorod Arrays as High-Performance Electrocatalysts for Water Oxidation2018Inngår i: Chemelectrochem, ISSN 2196-0216, Vol. 5, nr 15, s. 2064-2068Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Earth-abundant transition-metal-based oxides are potential candidates to replace the state-of-the-art noble-metal-based oxygen evolution catalysts (OECs) such as IrO2 and RuO2. Despite the low cost and large abundance, copper-based OER catalysts have been less frequently studied, mainly owing to the low electrical conductivity of copper oxides that results in large overpotential and sluggish kinetics for oxygen evolution. We report here the insitu fabrication of semi-metallic Cu3P nanorod arrays on commercial copper foam via a template approach; the resulting self-supported core-shell Cu-Cu3P/CuO electrode has the merits of high electrical conductivity, large active area, and short diffusion paths for electrolyte and evolved oxygen, exhibiting a low overpotential of 315mV and high durability over 50h at a current density of 10mAcm(-2) for OER in 1.0 M KOH. The remarkable OER performance reported here is not only superior to that of analogous Cu-CuO foam electrode, but also outperforms those of copper-based OER electrocatalysts in the literature.

  • 84.
    Dvinskikh, Sergey, V
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi. St Petersburg State Univ, Lab Biomol NMR, St Petersburg, Russia..
    Nuclear magnetic resonance studies of translational diffusion in thermotropic ionic liquid crystals2019Inngår i: Liquid crystals (Print), ISSN 0267-8292, E-ISSN 1366-5855Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The NMR methodologies employed for investigating translational diffusion in anisotropic fluids and the results of their applications to ionic liquid crystals are reviewed. Experiments on ionic liquid crystals are preferably performed using oriented samples and require magnetic field gradients in orthogonal directions. Diffusion experiments in anisotropic systems with broad NMR lines are performed using line narrowing techniques and by application of strong static or pulsed field gradients for efficient gradient encoding/decoding of the spatial locations of molecules. Self-diffusion studies on various thermotropic ion-conductive materials exhibiting smectic, cubic, and columnar phases have been reported. Diffusion rates and anisotropy characterise the translational dynamics of ions in nanostructures and reflect the molecular ordering and ion pairing/dissociation processes. Distinct diffusion behaviours were observed for cations and anions. The knowledge of molecular mobility in ionic liquid crystals is important for the understanding their dynamic properties and is, therefore, valuable for the development of anisotropic soft materials for ion transport.

  • 85.
    Dömstedt, Peter
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap.
    Lundberg, Mats
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap.
    Szakalos, Peter
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap.
    Corrosion Studies of Low-Alloyed FeCrAl Steels in Liquid Lead at 750 degrees C2019Inngår i: Oxidation of Metals, ISSN 0030-770X, E-ISSN 1573-4889, Vol. 91, nr 3-4, s. 511-524Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    New ductile experimental FeCrAl alloys, based on the composition of Fe-10Cr-4Al, were exposed to stagnant liquid lead at 750 degrees C for up to 1970h. Two exposures with different test conditions were performed: one with addition of oxygen (as H2O) to the liquid lead and one without. The experimental alloys showed generally good oxidation and self-healing properties. The exposures showed that this specific category of steels has the potential to operate in liquid lead at very high temperatures with only minor oxidation. With this new material development, new energy technologies such as the CSP plants may be able to utilize liquid lead at very high temperatures as heat transfer fluid, thus achieving increased thermal efficiency.

  • 86. Ekvall, Mikael T.
    et al.
    Hedberg, Jonas
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap.
    Wallinder, Inger Odnevall
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap.
    Hansson, Lars-Anders
    Cedervall, Tommy
    Long-term effects of tungsten carbide (WC) nanoparticles in pelagic and benthic aquatic ecosystems2018Inngår i: Nanotoxicology, ISSN 1743-5390, E-ISSN 1743-5404, Vol. 12, nr 1, s. 79-89Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    As the production and usage of nanomaterials are increasing so are the concerns related to the release of the material into nature. Tungsten carbide (WC) is widely used for its hard metal properties, although its use, in for instance tyre studs, may result in nano-sized particles ending up in nature. Here, we evaluate the potential long-term exposure effects of WC nanoparticles on a pelagic (Daphnia magna) and a benthic (Asellus aquaticus) organism. No long-term effects were observed in the benthic system with respect to population dynamics or ecosystem services. However, long-term exposure of D. magna resulted in increased time to first reproduction and, if the particles were resuspended, strong effects on survival and reproductive output. Hence, the considerable differences in acute vs. long-term exposure studies revealed here emphasize the need for more long-term studies if we are to understand the effects of nanoparticles in natural systems.

  • 87. Elawad, M.
    et al.
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Mola, G. T.
    Yu, Z.
    Arbab, E. A. A.
    Enhanced performance of perovskite solar cells using p-type doped PFB:F4TCNQ composite as hole transport layer2019Inngår i: Journal of Alloys and Compounds, ISSN 0925-8388, E-ISSN 1873-4669, Vol. 771, s. 25-32Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Conjugated polymers have been widely used as hole transport materials (HTM) in the preparation of mesoscopic perovskite solar cells (PSCs). In this work, we employed p-type doped conducting polymer known as poly(9,9-dioctylfluorene-co-bis-N,N-(-4-butyl phenyl)-bis-N,N-phenyl-1,4-phenylenediamine) (PFB) as a hole transport material (HTM) in perovskite based solar cell. The effect of dopant concentration on the optical and electrical properties of PEB was investigated to optimize the electrical properties of the material for the best function of the solar cell. The highest power conversion efficiency of mesoscopic perovskite solar cells (PSCs), fabricated in this investigation, was found to be 14.04% which is 57% higher than that of pristine PFB hole transport layer. The UV–Vis absorption and Raman spectroscopy measurements confirm the occurrence of oxidation in a p-type doped PFB hole transport layer. This is attributed to the transfer of electrons from the highest occupied molecular orbital (HOMO) of PEB to the lowest unoccupied molecular orbital (LUMO) of F4TCNQ. The solar cells produced using p-type doped PFB:F4TCNQ composite not only improves device performances but also shows superior long-term stability. The optical, morphological and electrical properties of the doped composite PFB: F4TCNQ and newly fabricated devices are presented and discussed in this paper.

  • 88. Elmhalli, Fawzeia
    et al.
    Garboui, Samira S.
    Borg-Karlson, Anna-Karin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Organisk kemi.
    Mozuraitis, Raimondas
    Baldauf, Sandra L.
    Grandi, Giulio
    The repellency and toxicity effects of essential oils from the Libyan plants Salvadora persica and Rosmarinus officinalis against nymphs of Ixodes ricinus2019Inngår i: Experimental & applied acarology, ISSN 0168-8162, E-ISSN 1572-9702, Vol. 77, nr 4, s. 585-599Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Essential oils extracted from the leaves of Libyan Rosemary (Rosmarinus officinalis L.), and Miswak (Salvadora persica L.) were evaluated for their acaricidal and repellent effects on Ixodes ricinus L. nymphs (Acari: Ixodidae) using a bioassay based on an open filter paper method'. Rosmarinus officinalis leaf essential oil diluted to 0.5 and 1 mu l/cm(2) in acetone exhibited, respectively, 20 and 100% tick mortality after about 5h of exposure. A total of 50 and 95% of I. ricinus nymphs were killed by direct contact with the oil when exposed to lethal concentrations (LC)of 0.7 mu l/cm(2) (LC50) and 0.95 mu l/cm(2) (LC95), respectively. The LC50 (0.5 mu l/cm(2)) was reached before the end of the first 24h of exposure time (ET), as tick mortality at 24h was 60%. Salvadora persica leaf essential oil at 1 mu l/cm(2) showed a significant repellency effect against I. ricinus nymphs at 1.5h ET. A 95% repellency was observed at a repellent concentration (RC95) of 1 mu l/cm(2) of S. persica, but no significant mortality was recorded at this dose of S. persica oil. Gas chromatography-mass spectrometry analyses showed that the main monoterpenes in both oils were 1,8-cineol, -pinene, and -pinene, although in markedly different proportions. These results suggest that essential oils have substantial potential as alternative approaches for I. ricinus tick control.

  • 89.
    Elmhalli, Fawzeia
    et al.
    Uppsala Univ, Evolutionary Biol Ctr, Dept Systemat Biol, Norbyvagen 18d, SE-75236 Uppsala, Sweden..
    Pålsson, Katinka
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Orberg, Jan
    Uppsala Univ, Dept Environm Toxicol, Evolutionary Biol Ctr, Uppsala, Sweden..
    Grandi, Giulio
    Swedish Univ Agr Sci SLU, Dept Biomed Sci & Vet Publ Hlth, Uppsala, Sweden..
    Acaricidal properties of ylang-ylang oil and star anise oil against nymphs of Ixodes ricinus (Acari: Ixodidae)2018Inngår i: Experimental & applied acarology, ISSN 0168-8162, E-ISSN 1572-9702, Vol. 76, nr 2, s. 209-220Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Ylang-ylang oil (YYO) from Cananga odorata (Lam.) Hook.f. & Thomson and star anise oil (SAO) from Illicium verum Hook.f. were tested at four concentrations 0.05, 0.1, 0.2, 0.4 mu l/cm(2). Mortality rates were obtained by counting dead nymphs at 30-min intervals during the first 5h after the start of exposure and then at 24, 48 and 72h. Mortality increased with increasing oil concentration and time of exposure. The two highest concentrations of YYO (0.2, 0.4 mu l/cm(2)) gave maximum lethal concentrations (LC) of 50 and 95% mortality after 4.5h exposure. Mortality of 95% was obtained after 24h with the next highest dose (0.1 mu l/cm(2)), whereas LC95 required 3days with the lowest YYO (0.05 mu l/cm(2)). The lethal effect time (LT) was correlated with the duration of exposure, with a significant effect at 0.4l YYO/cm(2) after 3h' (LT50=3.2h, LT95=4.3h). In contrast, only the highest concentration of SAO, 0.4 mu l SAO/cm(2), showed increasing mortality with time of exposure. This reached LT50 after 10h and LT95 after 24h. However, with the lower concentration (0.2 mu l/cm(2)) 50% mortality was reached after 24h and 100% at 72h. At to the lowest concentration of SAO (0.1 mu l/cm(2)), 67% mortality after 48h. The study indicates that YYO and SAO exhibit strong acaricidal properties against nymphs of I. ricinus and suggest that both YYO and SAO should be evaluated as potentially useful in the control of ticks.

  • 90. El-Seedi, H. R.
    et al.
    Khalifa, S. A. M.
    Taher, Eman A.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Farag, M. A.
    Saeed, A.
    Gamal, M.
    Hegazy, M. -EF.
    Youssef, D.
    Musharraf, S. G.
    Alajlani, M. M.
    Xiao, J.
    Efferth, T.
    Cardenolides: Insights from chemical structure and pharmacological utility2019Inngår i: Pharmacological Research, ISSN 1043-6618, E-ISSN 1096-1186, Vol. 141, s. 123-175Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Cardiac glycosides (CGs) are a class of naturally occurring steroid-like compounds, and members of this class have been in clinical use for more than 1500 years. They have been used in folk medicine as arrow poisons, abortifacients, heart tonics, emetics, and diuretics as well as in other applications. The major use of CGs today is based on their ability to inhibit the membrane-bound Na + /K + -ATPase enzyme, and they are regarded as an effective treatment for congestive heart failure (CHF), cardiac arrhythmia and atrial fibrillation. Furthermore, increasing evidence has indicated the potential cytotoxic effects of CGs against various types of cancer. In this review, we highlight some of the structural features of this class of natural products that are crucial for their efficacy, some methods of isolating these compounds from natural resources, and the structural elucidation tools that have been used. We also describe their physicochemical properties and several modern biotechnological approaches for preparing CGs that do not require plant sources.

  • 91.
    El-Seedi, Hesham R.
    et al.
    Uppsala Univ, Biomed Ctr, Dept Med Chem, Pharmacognosy Grp, Box 574, SE-75123 Uppsala, Sweden.;Jiangsu Univ, Coll Food & Biol Engn, Zhenjiang 212013, Jiangsu, Peoples R China.;Al Rayan Coll, Al Rayan Res & Innovat Ctr, Medina 42541, Saudi Arabia.;Menoufia Univ, Fac Sci, Dept Chem, Al Minufiyah, Egypt..
    El-Shabasy, Rehan M.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi. Menoufia Univ, Fac Sci, Dept Chem, Al Minufiyah, Egypt.
    Khalifa, Shaden A. M.
    Karolinska Univ Hosp, Clin Res Ctr, Huddinge, Sweden.;Stockholm Univ, Wenner Gren Inst, Dept Mol Biosci, SE-10691 Stockholm, Sweden..
    Saeed, Aamer
    Quaid I Azam Univ, Dept Chem, Islamabad 45320, Pakistan..
    Shah, Afzal
    Univ Bahrain, Coll Sci, Dept Chem, Sakhir 32038, Bahrain..
    Shah, Raza
    Univ Karachi, Int Ctr Chem & Biol Sci, HEJ Res Inst Chem, Karachi 75270, Pakistan..
    Iftikhar, Faiza Jan
    Quaid I Azam Univ, Dept Chem, Islamabad 45320, Pakistan..
    Abdel-Daim, Mohamed M.
    Suez Canal Univ, Fac Vet Med, Pharmacol Dept, Ismailia 41522, Egypt..
    Omri, Abdelfatteh
    KAU, Ctr Excellence Bionosci Res, Jeddah 21589, Saudi Arabia.;KAU, Dept Biol Sci, Biotechnol Res Grp, Fac Sci, Jeddah 21589, Saudi Arabia..
    Hajrahand, Nahid H.
    KAU, Ctr Excellence Bionosci Res, Jeddah 21589, Saudi Arabia.;KAU, Dept Biol Sci, Biotechnol Res Grp, Fac Sci, Jeddah 21589, Saudi Arabia..
    Sabir, Jamal S. M.
    KAU, Ctr Excellence Bionosci Res, Jeddah 21589, Saudi Arabia.;KAU, Dept Biol Sci, Biotechnol Res Grp, Fac Sci, Jeddah 21589, Saudi Arabia..
    Zou, Xiaobo
    Jiangsu Univ, Coll Food & Biol Engn, Zhenjiang 212013, Jiangsu, Peoples R China..
    Halabi, Mohammed F.
    Al Rayan Coll, Al Rayan Res & Innovat Ctr, Medina 42541, Saudi Arabia..
    Sarhan, Wessam
    Zewail City Sci & Technol, Cairo, Egypt..
    Guo, Weisheng
    Guangzhou Med Univ, Affiliated Hosp 2, Translat Med Ctr, Guangzhou 510260, Guangdong, Peoples R China..
    Metal nanoparticles fabricated by green chemistry using natural extracts: biosynthesis, mechanisms, and applications2019Inngår i: RSC Advances, ISSN 2046-2069, E-ISSN 2046-2069, Vol. 9, nr 42, s. 24539-24559Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    Nanoparticles (NPs) are new inspiring clinical targets that have emerged from persistent efforts with unique properties and diverse applications. However, the main methods currently utilized in their production are not environmentally friendly. With the aim of promoting a green approach for the synthesis of NPs, this review describes eco-friendly methods for the preparation of biogenic NPs and the known mechanisms for their biosynthesis. Natural plant extracts contain many different secondary metabolites and biomolecules, including flavonoids, alkaloids, terpenoids, phenolic compounds and enzymes. Secondary metabolites can enable the reduction of metal ions to NPs in eco-friendly one-step synthetic processes. Moreover, the green synthesis of NPs using plant extracts often obviates the need for stabilizing and capping agents and yields biologically active shape- and size-dependent products. Herein, we review the formation of metallic NPs induced by natural extracts and list the plant extracts used in the synthesis of NPs. In addition, the use of bacterial and fungal extracts in the synthesis of NPs is highlighted, and the parameters that influence the rate of particle production, size, and morphology are discussed. Finally, the importance and uniqueness of NP-based products are illustrated, and their commercial applications in various fields are briefly featured.

  • 92.
    Elwinger, Fredrik
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi. GE Healthcare Biosci AB, Bjorkgatan 31, SE-75184 Uppsala, Sweden..
    Wernersson, Jonny
    GE Healthcare Biosci AB, Bjorkgatan 31, SE-75184 Uppsala, Sweden..
    Furo, Istvan
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi. GE Healthcare Biosci AB, Bjorkgatan 31, SE-75184 Uppsala, Sweden..
    Quantifying Size Exclusion by Diffusion NMR: A Versatile Method to Measure Pore Access and Pore Size2018Inngår i: Analytical Chemistry, ISSN 0003-2700, E-ISSN 1520-6882, Vol. 90, nr 19, s. 11431-11438Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Size-exclusion quantification NMR spectroscopy (SEQNMR) is introduced for measuring equilibrium distribution coefficients, K-eq, in porous media. The porous medium is equilibrated with a polydisperse polymer solution. The original bulk polymer solution and the polymer solution after equilibration but in the absence of the porous medium are analyzed by NMR diffusion experiments. The joint evaluation of the two diffusion attenuation curves under suitable constraints provides the extent by which polymer fractions of particular size were depleted from the solution by pore access. This procedure yields K-eq versus polymer probe size, the selectivity curve that in turn can provide the pore size and its distribution. Simulations probe the performance of the method that is demonstrated experimentally in chromatographic media using dextran polymers. SEQ-NMR and inverse size- exclusion chromatography (ISEC) yield selectivity curves that virtually coincide. Crucial advantages with SEQ-NMR, such as versatility with regard to both the polymer used and porous system explored, high speed, potential for automation, and small required sample volume, are discussed.

  • 93.
    El-Zohry, Ahmed M.
    et al.
    Uppsala Univ, Dept Chem, Angstrom Labs, Box 523, SE-75120 Uppsala, Sweden..
    Karlsson, Karl Martin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi.
    Gigantic Relevance of Twisted Intramolecular Charge Transfer for Organic Dyes Used in Solar Cells2018Inngår i: The Journal of Physical Chemistry C, ISSN 1932-7447, E-ISSN 1932-7455, Vol. 122, nr 42, s. 23998-24003Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Within this work, we emphasis on the importance of twisted intramolecular charge transfer (TICT) process in organic dyes based on triphenyl amine moiety to achieve high performance in dye-sensitized solar cells. Through the comparison between two recent made dyes, Ll and L1Fc, on different semiconductors (TiO2, and ZrO2), we could spectrally and dynamically detect for the first time the formation of TICT state for Ll on ZrO2 after localized charge transfer (LCT) state population, and an electron injection process from TICT state on TiO2. However, for the excited L1Fc dye, the ultrafast electron transfer from ferrocene (Fc) moiety to the Ll unit quenched the formation of TICT state in L1Fc on semiconductors, leading instead to an electron injection process from the LCT state. The electron injection from TICT state in Ll associated with structural rearrangements on TiO2 leads to slow recombination process and an efficiency improvement of about 325%, compared to solar cells based on L1Fc dye, in which TICT state formation is hindered. Similar electron dynamics are obtained for Ll on TiO2 upon physically hindering the TICT process by adding polymer matrix. The presence of TICT state for Ll dye and similar triphenyl amine dyes aids to reconstruct the kinetic profile for these dyes on semiconductor surfaces, and to redesign organic dyes accordingly for higher efficiency in solar cells.

  • 94.
    Endrodi, Balazs
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Tillämpad elektrokemi. Sch Engn Sci Chem Univ Szeged, Dept Phys Chem & Mat Sci, Rerrich Bela Sq 1, H-6720 Szeged, Hungary..
    Stojanovic, Aleksandra
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Tillämpad elektrokemi.
    Cuartero, Maria
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi.
    Simic, Nina
    Nouryon Pulp & Performance Chem AB, Farjevagen 1, SE-44580 Bohus, Sweden..
    Wildlock, Mats
    Nouryon Pulp & Performance Chem AB, Farjevagen 1, SE-44580 Bohus, Sweden..
    de Marco, Roland
    Univ Sunshine Coast, Fac Sci Hlth Educ & Engn, Sippy Downs Dr 90, Sippy Downs, Qld 4556, Australia.;Univ Queensland, Sch Chem & Mol Biosci, Cooper Rd 68, Brisbane, Qld 4072, Australia..
    Crespo, Gaston A.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi.
    Cornell, Ann M.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Tillämpad elektrokemi.
    Selective Hydrogen Evolution on Manganese Oxide Coated Electrodes: New Cathodes for Sodium Chlorate Production2019Inngår i: ACS Sustainable Chemistry & Engineering, ISSN 2168-0485, Vol. 7, nr 14, s. 12170-12178Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The safety and feasibility of industrial electrochemical production of sodium chlorate, an important chemical in the pulp and paper industry, depend on the selectivity of the electrode processes. The cathodic reduction of anodic products is sufficiently suppressed in the current technology by the addition of chromium(VI) to the electrolyte, but due to the high toxicity of these compounds, alternative pathways are required to maintain high process efficiency. In this paper, we evaluate the electrochemical hydrogen evolution reaction kinetics and selectivity on thermally formed manganese oxide-coated titanium electrodes in hypochlorite and chlorate solutions. The morphology and phase composition of manganese oxide layers were varied via alteration of the annealing temperature during synthesis, as confirmed by scanning electron microscopy, X-ray diffraction, synchrotron radiation X-ray photoelectron spectroscopy, and near-edge X-ray absorption fine structure spectroscopy measurements. As shown in mass spectroscopy coupled electrochemical measurements, the hydrogen evolution selectivity in hypochlorite and chlorate solutions is dictated by the phase composition of the coating. Importantly, a hydrogen evolution efficiency of above 95% was achieved with electrodes of optimized composition (annealing temperature, thickness) in hypochlorite solutions. Further, these electrode coatings are nontoxic and Earth-abundant, offering the possibility of a more sustainable chlorate production.

  • 95.
    Eriksson, Björn
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Tillämpad elektrokemi.
    Montserrat-Sisó, Gerard
    Chalmers University of Technology.
    Brown, Rosemary
    Chalmers University of Technology.
    Lindström, Rakel
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi.
    Lindbergh, Göran
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Tillämpad elektrokemi.
    Wickman, Björn
    Chalmers University of Technology.
    Lagergren, Carina
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Tillämpad elektrokemi.
    Evaluation of rare earth metal alloy catalysts for the oxygen reduction reaction in proton exchange membrane fuel cellsManuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    To achieve large scale commercialization of fuel cells more active catalysts need to be developed. In this work highly active alloy catalysts of Pt3Y, Pt5Gd and Pt5Tb are evaluated in a proton exchange membrane fuel cell. The alloys are produced by sputter deposition onto gas diffusion layers. The alloy catalysts show activity increases between 2 and 2.5 times that of pure platinum. EDX and XPS analyses show that after acid cleaning a platinum overlayer is formed. After the electrochemical measurements, each alloy had different amounts of alloying element left, as well as different ratios between metallic and non-metallic rare earth metal, highlighting that the alloys are affected differently by the fuel cell measurements. However, the results show that the tested alloys are highly active and can significantly reduce the amount of platinum required. If the activation procedure is optimized, even higher activities might be achievable.

  • 96.
    Eriksson, Mimmi
    et al.
    RISE Res Inst Sweden, Stockholm, Sweden..
    Jarn, Mikael
    RISE Res Inst Sweden, Stockholm, Sweden..
    Tuominen, Mikko
    RISE Res Inst Sweden, Stockholm, Sweden..
    Wallqvist, Viveca
    RISE Res Inst Sweden, Stockholm, Sweden..
    Claesson, Per M.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap. RISE Res Inst Sweden, Stockholm, Sweden..
    Teisala, Hannu
    Max Planck Inst Polymer Res, Mainz, Germany..
    Vollmer, Doris
    Max Planck Inst Polymer Res, Mainz, Germany..
    Kappl, Michael
    Max Planck Inst Polymer Res, Mainz, Germany..
    Butt, Hans-Jurgen
    Max Planck Inst Polymer Res, Mainz, Germany..
    Gane, Patrick
    Omya Int AG, Oftringen, Switzerland. ; Aalto Univ, Espoo, Finland..
    Schoelkopf, Joachim
    Omya Int AG, Oftringen, Switzerland..
    Swerin, Agne
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap. RISE Res Inst Sweden, Stockholm, Sweden..
    Interactions at submerged liquid-repellent surfaces: Gas meniscus formation and development2019Inngår i: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 257Artikkel i tidsskrift (Annet vitenskapelig)
  • 97.
    Eriksson, Mimmi
    et al.
    RISE Res Inst Sweden, Biosci & Mat Surface, Proc & Formulat, SE-11486 Stockholm, Sweden.
    Tuominen, Mikko
    RISE Res Inst Sweden, Biosci & Mat Surface, Proc & Formulat, SE-11486 Stockholm, Sweden..
    Jarn, Mikael
    RISE Res Inst Sweden, Biosci & Mat Surface, Proc & Formulat, SE-11486 Stockholm, Sweden..
    Claesson, Per M.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap. RISE Research Institutes of Sweden, Bioscience and Materials − Surface, Process and Formulation, SE-114 86 Stockholm, Sweden.
    Wallqvist, Viveca
    RISE Res Inst Sweden, Biosci & Mat Surface, Proc & Formulat, SE-11486 Stockholm, Sweden..
    Butt, Hans Juergen
    Max Planck Inst Polymer Res, Dept Phys Interfaces, Ackermannweg 10, DE-55128 Mainz, Germany..
    Vollmer, Doris
    Max Planck Inst Polymer Res, Dept Phys Interfaces, Ackermannweg 10, DE-55128 Mainz, Germany..
    Kappl, Michael
    Max Planck Inst Polymer Res, Dept Phys Interfaces, Ackermannweg 10, DE-55128 Mainz, Germany..
    Schoelkopf, Joachim
    Omya Int AG, Baslerstr 42, CH-4665 Oftringen, Switzerland..
    Gane, Patrick A. C.
    Omya Int AG, Baslerstr 42, CH-4665 Oftringen, Switzerland.;Aalto Univ, Sch Chem Engn, Dept Bioprod & Biosyst, FI-00076 Aalto, Finland..
    Teisala, Hannu
    Max Planck Inst Polymer Res, Dept Phys Interfaces, Ackermannweg 10, DE-55128 Mainz, Germany..
    Swerin, Agne
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap. RISE Res Inst Sweden, Biosci & Mat Surface, Proc & Formulat, SE-11486 Stockholm, Sweden..
    Direct Observation of Gas Meniscus Formation on a Superhydrophobic Surface2019Inngår i: ACS Nano, ISSN 1936-0851, E-ISSN 1936-086X, Vol. 13, nr 2, s. 2246-2252Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The formation of a bridging gas meniscus via cavitation or nanobubbles is considered the most likely origin of the submicrometer long-range attractive forces measured between hydrophobic surfaces in aqueous solution. However, the dynamics of the formation and evolution of the gas meniscus is still under debate, in particular, in the presence of a thin air layer on a superhydrophobic surface. On superhydrophobic surfaces the range can even exceed 10 mu m. Here, we report microscopic images of the formation and growth of a gas meniscus during force measurements between a superhydrophobic surface and a hydrophobic microsphere immersed in water. This is achieved by combining laser scanning confocal microscopy and colloidal probe atomic force microscopy. The configuration allows determination of the volume and shape of the meniscus, together with direct calculation of the Young-Laplace capillary pressure. The long-range attractive interactions acting on separation are due to meniscus formation and volume growth as air is transported from the surface layer.

  • 98. Fan, Ke
    et al.
    Zou, Haiyuan
    Lu, Yue
    Beijing Univ Technol, Inst Microstruct & Properties Adv Mat, Beijing 100124, Peoples R China..
    Chen, Hong
    Li, Fusheng
    Liu, Jinxuan
    Sun, Licheng
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Tong, Lianpeng
    Toney, Michael F.
    Sui, Manling
    Yu, Jiaguo
    Direct Observation of Structural Evolution of Metal Chalcogenide in Electrocatalytic Water Oxidation2018Inngår i: ACS Nano, ISSN 1936-0851, E-ISSN 1936-086X, Vol. 12, nr 12, s. 12369-12379Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    As one of the most remarkable oxygen evolution reaction (OER) electrocatalysts, metal chalcogenides have been intensively reported during the past few decades because of their high OER activities. It has been reported that electron-chemical conversion of metal OER chalcogenides into oxides/hydroxides would take place after the OER. However, the transition mechanism of such unstable structures, as well as the real active sites and catalytic activity during the OER for these electrocatalysts, has not been understood yet; therefore a direct observation for the electrocatalytic water oxidation process, especially at nano or even angstrom scale, is urgently needed. In this research, by employing advanced Cs-corrected transmission electron microscopy (TEM), a step by step oxidational evolution of amorphous electrocatalyst CoSx into crystallized CoOOH in the OER has been in situ captured: irreversible conversion of CoSx to crystallized CoOOH is initiated on the surface of the electrocatalysts with a morphology change via Co(OH)(2) intermediate during the OER measurement, where CoOOH is confirmed as the real active species. Besides, this transition process has also been confirmed by multiple applications of X-ray photoelectron spectroscopy (XPS), in situ Fourier-transform infrared spectroscopy (FTIR), and other ex situ technologies. Moreover, on the basis of this discovery, a high-efficiency electrocatalyst of a nitrogen-doped graphene foam (NGF) coated by CoSx has been explored through a thorough structure transformation of CoOOH. We believe this in situ and in-depth observation of structural evolution in the OER measurement can provide insights into the fundamental understanding of the mechanism for the OER catalysts, thus enabling the more rational design of low-cost and high-efficient electrocatalysts for water splitting.

  • 99.
    Fan, Lizhou
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Zhang, Peili
    DUT, DUT KTH Joint Educ, Inst Artificial Photosynth, State Key Lab Fine Chem, Dalian 116024, Peoples R China.;DUT, Res Ctr Mol Devices, Dalian 116024, Peoples R China..
    Zhang, Biaobiao
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Daniel, Quentin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Timmer, Brian
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Zhang, Fuguo
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi.
    Sun, Licheng
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi. DUT, DUT KTH Joint Educ, Inst Artificial Photosynth, State Key Lab Fine Chem, Dalian 116024, Peoples R China.;DUT, Res Ctr Mol Devices, Dalian 116024, Peoples R China..
    3D Core-Shell NiFeCr Catalyst on a Cu Nanoarray for Water Oxidation: Synergy between Structural and Electronic Modulation2018Inngår i: ACS ENERGY LETTERS, ISSN 2380-8195, Vol. 3, nr 12, s. 2865-2874Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Low cost transition metal-based electrocatalysts for water oxidation and understanding their structure-activity relationship are greatly desired for clean and sustainable chemical fuel production. Herein, a core-shell (CS) NiFeCr metal/metal hydroxide catalyst was fabricated on a 3D Cu nanoarray by a simple electrodeposition-activation method. A synergistic promotion effect between electronic structure modulation and nanostructure regulation was presented on a CS-NiFeCr oxygen evolution reaction (OER) catalyst: the 3D nanoarchitecture facilitates the mass transport process, the in situ formed interface metal/metal hydroxide heterojunction accelerates the electron transfer, and the electronic structure modulation by Cr incorporation improves the reaction kinetics. Benefiting from the synergy between structural and electronic modulation, the catalyst shows excellent activity toward water oxidation under alkaline conditions: overpotential of 200 mV at 10 mA/cm(2) current density and Tafel slope of 28 mV/dec. This work opens up a new window for understanding the structure-activity relationship of OER catalysts and encourages new strategies for development of more advanced OER catalysts.

  • 100.
    Farahani, Saina Kishani
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Escalante, Alfredo
    Toriz, Guillermo
    Vilaplana, Francisco
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Gatenholm, Paul
    Hansson, Per
    Wågberg, Lars
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Experimental and Theoretical Evaluation of the Solubility/Insolubility Spruce Xylan (Arabino Glucuronoxylan)2019Inngår i: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 20, nr 3, s. 1263-1270Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The molecular solubility of softwood arabinoglucuronoxylan (AGX) has been thoroughly investigated, and it has been shown that the chemical and physical structures of the extracted hemicellulose are not significantly influenced by different purification steps, but a transient molecular solubility of AGX was observed in aqueous media at low concentrations (1 g/L) when the dissolved macromolecules had a hydrodynamic diameter of up to 10 nm. A phase separation was detected when the concentration was increased to 15 g/L leading to an association of the smaller molecules into fractal structures with a considerably larger diameter, even though the dispersions were still transparent to ocular inspection. Dynamic Light Scattering and Cryo-Transmission Electron Microscopy showed dimensions in the range of 1000 nm. The phase separation of the sample was further characterized by estimating the χ-interaction parameter of AGX in water using the Flory-Huggins theory, and the results supported that water is a poor solvent for AGX. This behavior is crucial when films and hydrogels based on these biopolymers are made, since the association will dramatically affect barrier and mechanical properties of films made from these materials.

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