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  • 701. Xie, Yongshu
    et al.
    Wei, Pingchun
    Li, Xin
    KTH, School of Biotechnology (BIO), Theoretical Chemistry and Biology.
    Hong, Tao
    Zhang, Kai
    Furuta, Hiroyuki
    Macrocycle Contraction and Expansion of a Dihydrosapphyrin Isomer2013In: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 135, no 51, 19119-19122 p.Article in journal (Refereed)
    Abstract [en]

    Cyclization of a pentapyrrane with two terminal beta-linked pyrroles afforded a dihydrosapphyrin isomer (1) with the pyrroles linked in a unique beta,alpha-alpha,beta mode, which was rather reactive, and thus it readily underwent a ring-contracted rearrangement to a pyrrolyl norrole (2), and succeeding ring expansion to a terpyrrole-containing isosmaragdyrin analogue (4). 1, 2, and 4 contain the internal ring pathways with a minimum of 17, 15, and 16 atoms, respectively. 1, 2, and 4 are almost nonfluorescent, whereas the complex of 2 with Zn2+ shows a distinct NIR emission peak at 741 nm. The unprecedented pyrrole transformation chemistry by confusion approach is illustrated.

  • 702.
    Xiong, Ruisheng
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Molecular Biomimetics.
    Arkhypchuk, Anna I.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Molecular Biomimetics.
    Kovacs, Daniel
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Molecular Biomimetics.
    Orthaber, Andreas
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Molecular Biomimetics.
    Borbas, K. Eszter
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Molecular Biomimetics.
    Directly linked hydroporphyrin dimers2016In: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, Vol. 52, no 58, 9056-9058 p.Article in journal (Refereed)
    Abstract [en]

    Directly linked hydroporphyrin (chlorin) dimers were accessed regioselectively from bromochlorins. Versatile 15-borylated chlorins were prepared in excellent yield via Miyaura borylation. Suzuki coupling yielded meso-beta-linked homo- and heterodimers, and meso-blinked dimers. The photophysical and electrochemical properties of the dimers are reported.

  • 703.
    Xiong, Ruisheng
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - BMC.
    Borbas, K. Eszter
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - BMC.
    Mild Microwave-Assisted Synthesis of Dipyrromethanes and Their Analogues2015In: Synlett: Accounts and Rapid Communications in Synthetic Organic Chemistry, ISSN 0936-5214, E-ISSN 1437-2096, Vol. 26, no 4, 484-488 p.Article in journal (Refereed)
    Abstract [en]

    The Mannich reaction between pyrroles or indoles and Eschenmoser's salt (dimethylmethylideneammonium iodide) forms N,N-dimethylamino-methylated derivatives in good to excellent yields. The reaction is highly regioselective, and for pyrroles both 2- and 3-substituted derivatives could be obtained. The N,N-dimethylaminomethylpyrroles and indoles underwent substitution with pyrrole under microwave irradiation, affording the appropriate dipyrromethanes, N-confused, and indolo-dipyrromethanes in moderate to excellent overall yield.

  • 704.
    Xu, Chao
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Lindgren, Fredrik
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Philippe, Bertrand
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Molecular and Condensed Matter Physics.
    Gorgoi, Mihaela
    Helmholtz Zentrum Berlin Germany.
    Björefors, Fredrik
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Edström, Kristina
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Gustafsson, Torbjörn
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Improved Performance of the Silicon Anode for Li-Ion Batteries: Understanding the Surface Modification Mechanism of Fluoroethylene Carbonate as an Effective Electrolyte Additive2015In: Chemistry of Materials, ISSN 0897-4756, E-ISSN 1520-5002, Vol. 27, no 7, 2591-2599 p.Article in journal (Refereed)
    Abstract [en]

    Silicon as a negative electrode material for lithium-ion batteries has attracted tremendous attention due to its high theoretical capacity, and fluoroethylene carbonate (FEC) was used as an electrolyte additive, which significantly improved the cyclability of silicon-based electrodes in this study. The decomposition of the FEC additive was investigated by synchrotron-based X-ray photoelectron spectroscopy (PES) giving a chemical composition depth-profile. The reduction products of FEC were found to mainly consist of LiF and -CHF-OCO2-type compounds. Moreover, FEC influenced the lithium hexafluorophosphate (LiPF6) decomposition reaction and may have suppressed further salt degradation. The solid electrolyte interphase (SEI) formed from the decomposition of ethylene carbonate (EC) and diethyl carbonate (DEC), without the FEC additive present, covered surface voids and lead to an increase in polarization. However, in the presence of FEC, which degrades at a higher reduction potential than EC and DEC, instantaneously a conformal SEI was formed on the silicon electrode. This stable SEI layer sufficiently limited the emergence of large cracks and preserved the original surface morphology as well as suppressed the additional SEI formation from the other solvent. This study highlights the vital importance of how the chemical composition and morphology of the SEI influence battery performance.

  • 705. Xu, Jing
    et al.
    Marsac, Remi
    Costa, Dominique
    Cheng, Wei
    Wu, Feng
    Boily, Jean-Francois
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Hanna, Khalil
    Co-Binding of Pharmaceutical Compounds at Mineral Surfaces: Molecular Investigations of Dimer Formation at Goethite/Water Interfaces2017In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 51, no 15, 8343-8349 p.Article in journal (Refereed)
    Abstract [en]

    The emergence of antibiotic and anti-inflammatory agents in aquatic and terrestrial systems is becoming a serious threat to human and animal health worldwide. Because pharmaceutical compounds rarely exist individually in nature, interactions between various compounds can have unforeseen effects on their binding to mineral surfaces. This work demonstrates this important possibility for the case of two typical antibiotic and anti-inflammatory agents (nalidixic acid (NA) and niflumic acid (NFA)) bound at goethite (alpha FeOOH) used as a model mineral surface. Our multidisciplinary study, which makes use of batch sorption experiments, vibration spectroscopy and periodic density functional theory calculations, reveals enhanced binding of the otherwise weakly bound NFA caused by unforeseen intermolecular interactions with mineral-bound NA. This enhancement is ascribed to the formation of a NFA NA dimer whose energetically favored formation (-0.5 eV compared to free molecules) is predominantly driven by van der Waals interactions. A parallel set of efforts also showed that no. cobinding occurred with sulfamethoxazole (SMX) because of the lack of molecular interactions with coexisting contaminants. As such, this article raises the importance of recognizing drug cobinding, and lack of cobinding, for predicting and developing policies on the fate of complex mixtures of antibiotics and anti-inflammatory agents in nature.

  • 706. Yager, Tom
    et al.
    Webb, Matthew J.
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - BMC, Physical Organic Chemistry.
    Grennberg, Helena
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - BMC, Physical Organic Chemistry.
    Yakimova, Rositsa
    Lara-Avila, Samuel
    Kubatkin, Sergey
    High mobility epitaxial graphene devices via aqueous-ozone processing2015In: Applied Physics Letters, ISSN 0003-6951, E-ISSN 1077-3118, Vol. 106, no 6, 063503Article in journal (Refereed)
    Abstract [en]

    We find that monolayer epitaxial graphene devices exposed to aggressive aqueous-ozone processing and annealing became cleaner from post-fabrication organic resist residuals and, significantly, maintain their high carrier mobility. Additionally, we observe a decrease in carrier density from inherent strong n-type doping to extremely low p-type doping after processing. This transition is explained to be a consequence of the cleaning effect of aqueous-ozone processing and annealing, since the observed removal of resist residuals from SiC/G enables the exposure of the bare graphene to dopants present in ambient conditions. The resulting combination of charge neutrality, high mobility, large area clean surfaces, and susceptibility to environmental species suggest this processed graphene system as an ideal candidate for gas sensing applications. (C) 2015 AIP Publishing LLC.

  • 707. Yan, H.
    et al.
    Zhu, L.
    Li, X.
    Kwok, A.
    Li, Xin
    KTH, School of Biotechnology (BIO), Theoretical Chemistry and Biology.
    Ågren, Hans
    KTH, School of Biotechnology (BIO), Theoretical Chemistry and Biology.
    Zhao, Y.
    Photothermal-responsive [2]rotaxanes2013In: RSC Advances, ISSN 2046-2069, Vol. 3, no 7, 2341-2350 p.Article in journal (Refereed)
    Abstract [en]

    Three photothermal-responsive α-cyclodextrin-based [2]rotaxanes were prepared via the copper(i)-catalyzed azide-alkyne cycloaddition, in which the α-cyclodextrin ring was threaded onto the azobenzene dumbbell component. The difference between the three [2]rotaxanes are the length of the ethylene glycol repeating chains connected between the azobenzene and triazole units in the dumbbell components. The α-cyclodextrin rings in the [2]rotaxanes can be reversibly switched between the azobenzene unit and triazole/ethylene glycol unit driven by the trans-cis isomerization of the azobenzene unit. The trans-to-cis isomerization of the azobenzene unit under UV light irradiation (365 nm) leads the α-cyclodextrin ring moving to the triazole/ethylene glycol unit, while the cis-to-trans isomerization of the azobenzene unit under either visible light irradiation or heating enables the α-cyclodextrin ring shuttling back to the azobenzene station. The different ethylene glycol repeating chains in the [2]rotaxanes can affect (1) the isomerization rates of the azobenzene units, i.e. the longer the chain, the faster the isomerization rate, and (2) fluorescent quantum yields of the [2]rotaxanes, i.e. the longer the chain, the lower the fluorescent quantum yield. In addition, the quantum yields of the [2]rotaxanes were enhanced by UV light irradiation and decreased back upon visible light irradiation or heating at 65 °C. The current research provides a fundamental understanding of the working mechanism for photothermal-responsive [2]rotaxanes.

  • 708.
    Yan, Jinyue
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Energy Processes. Mälardalen University, Sweden .
    Chou, S. K.
    Dahlquist, E.
    Li, H.
    Innovative Research For Sustainable Energy Systems2015In: International Journal of Green Energy, ISSN 1543-5075, E-ISSN 1543-5083, Vol. 12, no 3, 191-191 p.Article in journal (Other academic)
  • 709. Yang, Fengmei
    et al.
    Sun, Weiwei
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering. Uppsala University, Sweden .
    Li, Yuhan
    Yuan, Haiyan
    Dong, Zhiyong
    Li, Huanhuan
    Tian, Jumei
    Zheng, Yiying
    Zhang, Jingping
    Li2FePO4F and its metal-doping for Li-ion batteries: an ab initio study2014In: RSC Advances, ISSN 2046-2069, E-ISSN 2046-2069, Vol. 4, no 91, 50195-50201 p.Article in journal (Refereed)
    Abstract [en]

    The electrochemical properties of three isotopic Li2FePO4F compounds, as cathode materials under different space groups Pbcn, P (1) over bar and Pnma were investigated using first principle calculations. Their structures and average open circuit voltages for step delithiation reactions were explored, and the results are in good agreement with the reported experimental data. We estimate the substitution effect of Fe by Co in Pnma-Li2FePO4F. The substitution of Fe by Co in Li2Fe1-xCoxPO4F may enhance the discharge potential of the materials, and the rate of its volume change during the redox process is between 0.6% and 2.1%. Furthermore, from the projected density of states for Li2Fe0.5Co0.5PO4F, we found strong hybridization for Fe-3d and Co-3d bands near the Fermi level, which implies that the Co-doped Li2Fe1-xCoxPO4F may possess better electronic conductivity than the pure phase.

  • 710. Yang, Jie
    et al.
    Yu, Xinhai
    Yan, Jinyue
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Energy Processes.
    Tu, Shan-Tung
    CO2 Capture Using Amine Solution Mixed with Ionic Liquid2014In: Industrial & Engineering Chemistry Research, ISSN 0888-5885, E-ISSN 1520-5045, Vol. 53, no 7, 2790-2799 p.Article in journal (Refereed)
    Abstract [en]

    It is a focus to reduce the energy consumption and operating cost of CO2 capture from low-pressure flue gas streams of power plants using an aqueous amine-based absorbent. In this study, CO2 capture experiments were conducted in an absorption-desorption loop system using amine-based absorbents. The gas mixture containing CO2, O-2, SO2, and N-2 in the composition range of flue gas from coal-fired power plant after flue gas desulfurization was selected as the feed gas. For an aqueous amine solution, the largest contribution to monoethanolamine (MEA) loss was made by evaporation during desorption, followed by the formation of sulfate and heat-stable salts. To reduce MBA loss and meanwhile decrease the energy consumption during CO2 desorption, an aqueous amine solution mixed with ionic liquid (30 wt % MBA + 40 wt % [bmim][BF4] + 30 wt % H2O) was proposed. The energy consumption of the mixed ionic liquid solution for absorbent regeneration was 37.2% lower than that of aqueous MEA solution. The MEA loss per ton of captured CO2 for the mixed solution was 1.16 kg, which is much lower than that of 3.55 kg for the aqueous amine solution. No ionic liquid loss was detected. In addition, the mixed ionic liquid solution showed a low viscosity of 3.54 mPa s at 323 K, indicating that the ionic liquid disadvantage of high viscosity can be overcome for absorbent delivery of CO2 capture.

  • 711. Yang, Lei
    et al.
    Zhang, Jinbao
    Shen, Yang
    Park, Byung-Wook
    Bi, Dongqin
    Häggman, Leif
    Johansson, Erik M. J.
    Boschloo, Gerrit
    Hagfeldt, Anders
    Vlachopoulos, Nick
    Snedden, Alan
    KTH, School of Chemical Science and Engineering (CHE), Chemistry.
    Kloo, Lars
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Applied Physical Chemistry.
    Jarboui, Adel
    Chams, Amani
    Perruchot, Christian
    Jouini, Mohamed
    New Approach for Preparation of Efficient Solid-State Dye-Sensitized Solar Cells by Photoelectrochemical Polymerization in Aqueous Micellar Solution2013In: Journal of Physical Chemistry Letters, ISSN 1948-7185, E-ISSN 1948-7185, Vol. 4, no 23, 4026-4031 p.Article in journal (Refereed)
    Abstract [en]

    Hereby, we present a new, cost-effective, and environmentally friendly method of preparing an efficient solid-state dye-sensitized solar cell (sDSC) using a PEDOT conducting polymer as the hole conductor and a recently developed organic sensitizer. PEDOT is generated and deposited on the dye-sensitized TiO2 electrode by in situ photoelectropolymerization of bis-EDOT in aqueous micellar solution. The advantages of this approach are the use of water as the solvent and the obtainment of a sDSC simply by adding a silver layer on the as-obtained polymer film deposited on dye/TiO2 without the need for electrolytic solution. The sDSC containing the film prepared as above is compared to those where the organic dye is used to generate the same polymer film but in organic solvent. The energy conversion efficiency values of the two cells appear comparable, 4.8% for sDSC prepared in the aqueous-phase polymerized PEDOT and 6% for the sDSC prepared with in organic-phase polymerized PEDOT.

  • 712.
    Yang, Li
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Mihali, Viorica-Alina
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Karlsson, Christoffer
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Sjödin, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Strömme, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Brandell, Daniel
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Conjugated polymers as anodes in organic matter based batteries2014Conference paper (Other academic)
  • 713.
    Yang, Miao
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Applied Physical Chemistry.
    Barreiro Fidalgo, Alexandre
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Applied Physical Chemistry.
    Sundin, Sara
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Applied Physical Chemistry.
    Jonsson, Mats
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Applied Physical Chemistry.
    Inhibition of radiation induced dissolution of UO2 by sulfide-A comparison with the hydrogen effect2013In: Journal of Nuclear Materials, ISSN 0022-3115, E-ISSN 1873-4820, Vol. 434, no 1-3, 38-42 p.Article in journal (Refereed)
    Abstract [en]

    In this work we have studied the influence of H2S on radiation induced dissolution of spent nuclear fuel using simple model systems. The reaction between H2O2 and H2S/HS- has been studied experimentally as well as the effect of H2S/HS - on γ-radiation induced dissolution of a UO2 pellet. The experiments clearly show that the reaction of H2O 2 and H2S/HS- is fairly rapid and that H 2O2 and H2S/HS- stoichiometry is favorable for inhibition. Radiolysis experiments show that H2S/ HS- can effectively protect UO2 from oxidative dissolution. The effect depends on sulfide concentration in combination with dose rate. Autoclave experiments were also conducted to study the role of H 2S/HS- in the reduction of U(VI) in the presence and absence of H2 and Pd particles in anoxic aqueous solution. The aqueous solutions were pressurized with H2 or N2 and two different concentrations of H2S/HS- were used in the presence and absence of Pd. No catalytic effect of Pd on the U(VI) reduction by H2S/HS- could be found in N2 atmosphere. U(VI) reduction was found to be proportional to H2S/HS- concentration in H2 and N2 atmosphere. It is clearly shown the Pd catalyzed H2 effect is more powerful than the effect of H2S/HS-. H2S/HS- poisoning of the Pd catalyst is not observed under the present conditions.

  • 714.
    Yang Nilsson, Ting
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biomolecular and Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Wagner, Michal
    Linköping University, Department of Physics, Chemistry and Biology, Biomolecular and Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Inganäs, Olle
    Linköping University, Department of Physics, Chemistry and Biology, Biomolecular and Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Lignin Modification for Biopolymer/Conjugated Polymer Hybrids as Renewable Energy Storage Materials2015In: ChemSusChem, ISSN 1864-5631, E-ISSN 1864-564X, Vol. 8, no 23, 4081-4085 p.Article in journal (Refereed)
    Abstract [en]

    Lignin derivatives, which arise as waste products from the pulp and paper industry and are mainly used for heating, can be used as charge storage materials. The charge storage function is a result of the quinone groups formed in the lignin derivative. Herein, we modified lignins to enhance the density of such quinone groups by covalently linking monolignols and quinones through phenolation. The extra guaiacyl, syringyl, and hydroquinone groups introduced by phenolation of kraft lignin derivatives were monitored by P-31 nuclear magnetic resonance and size exclusion chromatography. Electropolymerization in ethylene glycol/tetraethylammonium tosylate electrolyte was used to synthesize the kraft lignin/polypyrrole hybrid films. These modifications changed the phenolic content of the kraft lignin with attachment of hydroquinone units yielding the highest specific capacity (around 70mAhg(-1)). The modification of softwood and hardwood lignin derivatives yielded 50% and 23% higher charge capacity than the original lignin, respectively.

  • 715. Yang, Yong
    et al.
    Wang, Mei
    Xue, Liqin
    KTH, School of Biotechnology (BIO), Theoretical Chemistry and Biology.
    Zhang, Fengbo
    Chen, Lin
    Ahlquist, Mårten S. G.
    KTH, School of Biotechnology (BIO), Theoretical Chemistry and Biology.
    Sun, Licheng
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry. State Key Laboratory of Fine Chemicals, DUT-KTH Education and Research Centre on Molecular Devices, Dalian University of Technology (DUT), China.
    Nickel Complex with Internal Bases as Efficient Molecular Catalyst for Photochemical H-2 Production2014In: ChemSusChem, ISSN 1864-5631, E-ISSN 1864-564X, Vol. 7, no 10, 2889-2897 p.Article in journal (Refereed)
    Abstract [en]

    A Ni complex with internal bases that contain bipyridine-derived ligands, [Ni(L)(2)(H2O)(2)](BF4)(2) ([1](BF4)(2), L=2-(2-pyridyl)-1,8-naphthyridine), and a reference complex that bears analogous bipyridine-derived ligands but without an internal base, [Ni(L)(3)](BF4)(2) ([2](BF4)(2), L=2-(2-pyridyl)quinoline), were synthesized and characterized. The electrochemical properties of these complexes were studied in CH3CN, H2O, and a mixture of EtOH/H2O. The fluorescence spectroscopic studies suggest that both dynamic and the sphere-of-action static quenching exist in the fluorescein Fl(2-)/[1](2+) and Fl(2-)/[2](2+) systems. These noble-metal-free molecular systems were studied for photocatalytic H-2 generation. Under optimal conditions, the turnover number of H-2 evolution reaches 3230 based on [1](2+), whereas [2](2+) displays only approximately one third of the turnover of [1](2+). A plausible mechanism for the catalytic H-2 generation by [1](2+) is presented based on DFT calculations.

  • 716. Ye, Chen-Qing
    et al.
    Hu, Rong-Gang
    Dong, Shi-Gang
    Zhang, Xiao-Juan
    Hou, Rui-Qing
    Du, Rong-Gui
    Lin, Chang-Jian
    Pan, Jin-Shan
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Surface and Corrosion Science.
    EIS analysis on chloride-induced corrosion behavior of reinforcement steel in simulated carbonated concrete pore solutions2013In: Journal of Electroanalytical Chemistry, ISSN 1572-6657, Vol. 688, 275-281 p.Article in journal (Refereed)
    Abstract [en]

    The corrosion behavior of reinforcement steel in simulated carbonated concrete pore (SCCP) solution containing different concentrations of chloride was studied by electrochemical impedance spectroscopy (EIS) and linear polarization resistance (LPR) measurements simultaneously, and the topographies of the steel specimens and the elemental distribution at corrosion area were examined by scanning electron microscope (SEM)/electron microprobe analysis (EMPA). The results showed the capacitive loop and polarization resistance decreased with chloride increasing. Furthermore, when the chloride concentration reached a critical value, the Bode plots obviously exhibited two phase angle peaks indicating two time constants. However, when the chloride content exceeded a critical value, the phase angle peaks decreased to one phenomenal peak. An equivalent circuit with two RC loops was used to characterize the corrosion behavior of reinforcement steel in SCCP solution according to the measurements of EIS. Based on the dependence of the equivalent circuit elements on chloride content and immersion time, the formation, growth and breakdown of passive film of the steel were discussed. It was found that the EIS evaluation of corrosion behavior for reinforcement steel in SCCP solution was good agreement with the LPR and SEM measurements. The EMPA mapping revealed MnS inclusions at steel surface play a leading role in the initiation of pitting corrosion.

  • 717.
    Yin, Ge
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry. Stockholm University.
    Organohalogen contaminants in wildlife from the Yangtze River Delta: Development of methods and assessments of legacy and emerging persistent organic pollutants2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Rapid economic development has occurred during the past few decades in China with the Yangtze River Delta (YRD) area as one of the most progressive areas. The urbanization, industrialization, agricultural and aquaculture activities result in extensive production and application of chemicals. Organohalogen contaminants (OHCs) have been widely used as i.e. pesticides, flame retardants and plasticizers. They are persistent, bioaccumulative and pose a potential threat to ecosystem and human health. However, limited research has been conducted in the YRD with respect to chemicals environmental exposure.

    The main objective of this thesis is to investigate the contamination level, distribution pattern and sources of OHCs in the YRD. Wildlife from different habitats are used to indicate the environmental pollution situation, and evaluate selected matrices for use in long term biomonitoring to determine the environmental stress the contamination may cause. In addition, a method is developed for dicofol analysis. Moreover, a specific effort is made to introduce statistic power analysis to assist in optimal sampling design.

    The thesis results show extensive contamination of OHCs in wildlife in the YRD. The occurrences of high concentrations of chlorinated paraffins (CPs) are reported in wildlife, in particular in terrestrial species, (i.e. short-tailed mamushi snake and peregrine falcon). Impurities and byproducts of pentachlorophenol products, i.e. polychlorinated diphenyl ethers (PCDEs) and hydroxylated polychlorinated diphenyl ethers (OH-PCDEs) are identified and reported for the first time in eggs from black-crowned night heron and whiskered tern. High concentrations of octachlorodibenzo-p-dioxin (OCDD) are determined in these samples. The toxic equivalents (TEQs) of polychlorinated dibenzo-p-dioxin (PCDDs) and polychlorinated dibenzofurans (PCDFs) are at mean levels of 300 and 520 pg TEQ g-1lw (WHO2005 TEQ) in eggs from the two bird species, respectively. This is two orders of magnitude higher than European Union (EU) regulation limit in chicken eggs. Also, a novel pattern of polychlorinated biphenyls (PCBs) with octa- to decaCBs, contributing to as much as 20% of total PCBs therein, are reported in birds. The legacy POPs shows a common characteristic with relatively high level of organochlorine pesticides (i.e. DDT, hexacyclohexanes (HCHs) and Mirex), indicating historic applications. In contrast, rather low concentrations are shown of industrial chemicals such as PCBs and polybrominated diphenyl ethers (PBDEs).

    A refined and improved analytical method is developed to separate dicofol from its major decomposition compound, 4,4’-dichlorobenzophenone. Hence dicofol is possible to assess as such. Statistic power analysis demonstrates that sampling of sedentary species should be consistently spread over a larger area to monitor temporal trends of contaminants in a robust manner.

    The results presented in this thesis show high CPs and OCDD concentrations in wildlife. The levels and patterns of OHCs in YRD differ from other well studied areas of the world. This is likely due to the extensive production and use of chemicals in the YRD. The results strongly signal the need of research biomonitoring programs that meet the current situation of the YRD. Such programs will contribute to the management of chemicals and environment in YRD, with the potential to grow into the human health sector, and to expand to China as a whole.

  • 718.
    Yin, Ge
    et al.
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Danielsson, Sara
    Dahlberg, Anna-Karin
    Zhou, Yihui
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Qiu, Yanling
    Stockholm University, Faculty of Science, Department of Environmental Science and Analytical Chemistry.
    Nyberg, Elisabeth
    Bignert, Anders
    Sampling designs for contaminant temporal trend analyses using sedentary species exemplified by the snails (Bellamya aeruginosa) and (Viviparus viviparus)Manuscript (preprint) (Other academic)
  • 719. Yli-Rantala, E.
    et al.
    Pasanen, A.
    Kauranen, P.
    Ruiz, V.
    Borghei, M.
    Kauppinen, E.
    Oyarce, Alejandro
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Applied Electrochemistry.
    Lindbergh, Göran
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Applied Electrochemistry.
    Lagergren, Carina
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Applied Electrochemistry.
    Darab, M.
    Sunde, S.
    Thomassen, M.
    Ma-Andersen, S.
    Skou, E.
    Graphitised Carbon Nanofibres as Catalyst Support for PEMFC2011In: Fuel Cells, ISSN 1615-6846, E-ISSN 1615-6854, Vol. 11, no 6, 715-725 p.Article in journal (Refereed)
    Abstract [en]

    Graphitised carbon nanofibres (G-CNFs) show superior thermal stability and corrosion resistance in PEM fuel cell environment over traditional carbon black (CB) and carbon nanotube catalyst supports. However, G-CNFs have an inert surface with only very limited amount of surface defects for the anchorage of Pt catalyst nanoparticles. Modification of the fibre surface is therefore needed. In this study Pt nanoparticles have been deposited onto as-received and surface-modified G-CNFs. The surface modifications of the fibres comprise acid treatment and nitrogen doping by pyrolysis of a polyaniline (PANI) precursor. The modified surfaces were studied by FTIR and XPS and the electrochemical characterization, including long-term Pt stability tests, was performed using a low-temperature PEMFC single cell. The performance and stability of the G-CNF supported catalysts were compared with a CB supported catalyst and the effects of the different surface treatments were discussed. On the basis of these results, new membrane electrode assemblies (MEAs) were manufactured and tested also for carbon corrosion by in situ FTIR analysis of the cathode exhaust gases. It was observed that the G-CNFs showed 5?times lower carbon corrosion compared to CB based catalyst when potential reached 1.5?V versus RHE in simulated start/stop cycling.

  • 720.
    Zaleśny, Robert
    KTH, School of Biotechnology (BIO), Theoretical Chemistry and Biology.
    Anharmonicity contributions to the vibrational first and second hyperpolarizability of para-disubstituted benzenes2014In: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 595, 109-112 p.Article in journal (Refereed)
    Abstract [en]

    In this Letter, we report on the anharmonicity contributions to the static vibrational first and second hyperpolarizability of para-disubstituted benzenes. MP2 and CCSD methods are used to determine the properties in question and, for 4-aminobenzaldehyde, we estimate the nuclear relaxation and electronic contribution to the longitudinal first hyperpolarizability at the CCSD(T)/aug-cc-pVTZ level of theory. This Letter demonstrates the importance of anharmonic contributions encompassed in the nuclear relaxation first and second hyperpolarizability. Moreover, it also points up the weakness of the double harmonic model which, in some instances, yields the incorrect sign of the vibrational contribution.

  • 721.
    Zanzi Vigouroux, Rolando
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Chemical Technology.
    Torrefaction as pre-treatment for improvement of the biomass properties prior combustion and gasification2010Conference paper (Other academic)
  • 722.
    Zanzi Vigouroux, Rolando
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Chemical Technology.
    Lundborg, Lina
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology.
    Rivero González, Julio
    Universidad de Pinar del Río, Cuba.
    Biodiesel production from an alkaline transesterification of vegetable oil and ethanol2010Conference paper (Other academic)
  • 723. Zhang, Biaobiao
    et al.
    Li, Fei
    Yu, Fengshou
    Cui, Honghua
    Zhou, Xu
    Li, Hua
    Wang, Yong
    Sun, Licheng
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry. KTH, School of Chemical Science and Engineering (CHE), Centres, Centre of Molecular Devices, CMD.
    Homogeneous Oxidation of Water by Iron Complexes with Macrocyclic Ligands2014In: Chemistry - An Asian Journal, ISSN 1861-4728, E-ISSN 1861-471X, Vol. 9, no 6, 1515-1518 p.Article in journal (Refereed)
    Abstract [en]

    The activity of eleven separated iron complexes and nine in situ-generated iron complexes towards catalytic water oxidation have been examined in aqueous solutions with Ce(NH4)(2)(NO3)(6) as the oxidant. Two iron complexes bearing tridentate and tetradentate macrocyclic ligands were found to be novel water oxidation catalysts. The one with tetradentate ligand exhibited a promising activity with a turnover number of 65 for oxygen evolution.

  • 724. Zhang, Biaobiao
    et al.
    Li, Fei
    Yu, Fengshou
    Wang, Xiaohong
    Zhou, Xu
    Li, Hua
    Jiang, Yi
    Sun, Licheng
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry. KTH, School of Chemical Science and Engineering (CHE), Centres, Centre of Molecular Devices, CMD.
    Electrochemical and Photoelectrochemical Water Oxidation by Supported Cobalt-Oxo Cubanes2014In: ACS Catalysis, ISSN 2155-5435, Vol. 4, no 3, 804-809 p.Article in journal (Refereed)
    Abstract [en]

    Cobalt-oxo cubane clusters were immobilized on a Nafion film-coated fluorine-doped tin oxide (FTO) electrode and an alpha-Fe2O3 photoanode as surface catalysts for water oxidation. The performance of electrochemical water splitting indicated that these earth-abundant metal complexes retain their homogeneous reactivity on the electrode. Furthermore, efficient visible light-driven water oxidation was realized by coupling a molecular electrocatalyst with an inorganic semiconductor as a noble metal-free photoanode, showing a stability significantly improved with respect to that of the homogeneous system.

  • 725.
    Zhang, Biaobiao
    et al.
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Li, Y.
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Valvo, Mario
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Fan, L.
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Daniel, Q.
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Zhang, P.
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Wang, L.
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Sun, L.
    KTH Royal Institute of Technology, Stockholm, Sweden; Dalian University of Technology, Dalian, China.
    Electrocatalytic Water Oxidation Promoted by 3 D Nanoarchitectured Turbostratic δ-MnOx on Carbon Nanotubes2017In: ChemSusChem, ISSN 1864-5631, E-ISSN 1864-564X, Vol. 10, no 22, 4472-4478 p.Article in journal (Refereed)
    Abstract [en]

    The development of manganese-based water oxidation electrocatalysts is desirable for the production of solar fuels, as manganese is earth-abundant, inexpensive, non-toxic, and has been employed by the Photosystem II in nature for a billion years. Herein, we directly constructed a 3 D nanoarchitectured turbostratic δ-MnOx on carbon nanotube-modified nickel foam (MnOx/CNT/NF) by electrodeposition and a subsequent annealing process. The MnOx/CNT/NF electrode gives a benchmark catalytic current density (10 mA cm−2) at an overpotential (η) of 270 mV under alkaline conditions. A steady current density of 19 mA cm−2 is obtained during electrolysis at 1.53 V for 1.0 h. To the best of our knowledge, this work represents the most efficient manganese-oxide-based water oxidation electrode and demonstrates that manganese oxides, as a structural and functional model of oxygen-evolving complex (OEC) in Photosystem II, can also become comparable to those of most Ni- and Co-based catalysts.

  • 726.
    Zhang, Fan
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Surface and Corrosion Science.
    Xie, Guoxin
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Surface and Corrosion Science. Tsinghua University, China.
    Pan, Jinshan
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Surface and Corrosion Science.
    Tunable Adsorption and Film Formation of Mussel Adhesive Protein by Potential Control2017In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 33, no 35, 8749-8756 p.Article in journal (Refereed)
    Abstract [en]

    Mussel adhesive proteins are of great interest in many applications because of their outstanding adhesive property and film forming ability. Understanding and controlling the film formation and its performance is crucial for the effective use of such proteins. In this study, we focus on the potential controlled film formation and compaction of one mussel adhesive protein, Mefp-1. The adsorption and film-forming behavior of Mefp-1 on a platinum (Pt) substrate under applied potentials were investigated by cyclic voltammetry, potential-controlled electro-chemical impedance spectroscopy (EIS), and quartz crystal microbalance with dissipation monitoring (QCM-D). Moreover, microfriction measurements were performed to evaluate the mechanical properties of the Mefp-1 films formed at selected potentials. The results led to the conclusion that Mefp-1 adsorbs on the Pt substrate through both electrostatic and nonelectrostatic interactions and shows an effective blocking effect for the electroactive sites on the substrate. The properties of the adsorbed Mefp-1 film vary with the applied potential, and the compactness of the adsorbed Mefp-1 film can be reversibly tuned by the applied potential.

  • 727.
    Zhang, Liming
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology.
    Chemical structure of condensed tannins from 8 different tree species studied by NMR techniques2011In: 16th International Symposium on Wood, Fiber and Pulping Chemistry: Proceedings, ISWFPC, Tianjin, China, 2011, 93-97 p.Conference paper (Refereed)
    Abstract [en]

    NMR techniques were applied to study and to compare the chemical structure of tannins from 8 different tree species, i.e., Norway spruce (Picea abies), Scots pine (Pinus sylvestris), larch (Larix gmelini), French maritime pine bark extractive, Quebracho (Schinopsis lorentzii), black wattle (Acacia mearnsii), Mangium (Acacia mangium) and Chinese Bayberry tree (Myrica rubra). The tannins from Norway spruce bark and Scots pine bark were extracted in our laboratory by using fresh bark harvested in Stockholmarea. The other tannins were obtained as commercial samples. It was found in this study that the complicated chemical structures of condensed tannins can be elucidated by applying 13C, DEPT90, and 2D HSQC NMR techniques. The tannins from pines and larch were found to be structurally similar to each other, containing mainly the procyanidins. In the case of Norway spruce tannin, stilbene polymer or stilbene- procyanidin co-polymer were found to comprise about half of the tannin content together with procyanidins. Quebracho tannin was found to contain predominantly the profisetinidins, in agreement with results of other earlier studies. Black wattle tannin was also found to contain profisetinidins as the major components, and proanthocyanidins and probably prorobinetinidins as the minor components. Tannin from Mangium was found to contain the prorobinetinidins as the major components. The Chinese Bayberry (Myrica rubra) tannin, however was found to contain mainly the prorobinetinidins and also small amount of the prodelphinidins.

  • 728. Zhang, Linlin
    et al.
    Gao, Yan
    Ding, Xin
    Yu, Ze
    Sun, Licheng
    KTH, School of Biotechnology (BIO), Theoretical Chemistry and Biology. State Key Laboratory of Fine Chemicals, Institute of Artificial Photosynthesis, DUT-KTH Joint Education and Research Center on Molecular Devices, Dalian University of Technology (DUT), China.
    High-Performance Photoelectrochemical Cells Based on a Binuclear Ruthenium Catalyst for Visible-Light-Driven Water Oxidation2014In: ChemSusChem, ISSN 1864-5631, E-ISSN 1864-564X, Vol. 7, no 10, 2801-2804 p.Article in journal (Refereed)
    Abstract [en]

    Two photoanodes based on a binuclear (2) and a mononuclear ruthenium (3) water oxidation catalysts were assembled in combination with a molecular photosensitizer (1) by using a co-adsorption method. The anodes were used in dye-sensitized photoelectrochemical cells (DS-PECs) for visible-light-driven water splitting. A DS-PEC device using TiO2(1+2) as working electrode (WE) exhibits better performance than TiO2(1+3) as WE in light-driven water splitting. Detailed photoelectrochemical studies on these DS-PEC devices are discussed.

  • 729. Zhang, Peili
    et al.
    Wang, Mei
    Gloaguen, Frederic
    Chen, Lin
    Quentelb, Francois
    Sun, Licheng
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry. KTH, School of Chemical Science and Engineering (CHE), Centres, Centre of Molecular Devices, CMD.
    Electrocatalytic hydrogen evolution from neutral water by molecular cobalt tripyridine-diamine complexes2013In: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, Vol. 49, no 82, 9455-9457 p.Article in journal (Refereed)
    Abstract [en]

    A cobalt complex with a tripyridine-diamine pentadentate ligand was found to be a highly active catalyst for electrochemical H-2 production from neutral water, with an activity of 860 mol H-2 (mol cat)(-1) h(-1) (cm(2) Hg)(-1) over 60 h CPE experiment at-1.25 V in a pH 7 phosphate buffer solution, without considerable deactivation.

  • 730. Zhang, Qi-Wei
    et al.
    Li, Dengfeng
    Li, Xin
    KTH, School of Biotechnology (BIO), Theoretical Chemistry and Biology.
    White, Paul B.
    Mecinovic, Jasmin
    Ma, Xiang
    Ågren, Hans
    KTH, School of Biotechnology (BIO), Theoretical Chemistry and Biology.
    Nolte, Roeland J. M.
    Tian, He
    Multicolor Photoluminescence Including White-Light Emission by a Single Host-Guest Complex2016In: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 138, no 41, 13541-13550 p.Article in journal (Refereed)
    Abstract [en]

    Achieving multicolor photoluminescence, 'especially white-light emission, under mild conditions based on a single "fluorescent compound-is a great challenge. Herein, we report a novel colorful-emission host guest complex BPCY, which is composed of a two-arm fluorescent guest molecule (BPC) and gamma-cyclodextrin (gamma-CD) as the host-molecule. BPC bears a unique asymmetrical donor acceptor donor (D-1-A(+)similar to D-2)-type structure, where D-1, A(+), and D-2 stand for the binaphthol electron donor, pyridinium electron acceptor, and coumarin electron donor, respectively. The luminescence property of BPC shows dual-sensitivity, i.e., toward the excitation wavelength and the cyclodextrin host molecule. Under certain conditions, the complex shows three different emission wavelengths, allowing the realization of multicolor photoluminescence, including red (R), green (G), and blue (B) as well as various intermediate colors by orthogonally modulating these two stimuli. In this way, nearly pure white-light emission with CIE coordinates (0.33, 0.34) could be generated. A combination of structural, spectroscopic, and computational simulation studies revealed the occurrence of synergetic mechanistic processes for the stimuli-responsive multicolor luminescence of the BPCY complex, namely, host-enhanced intramolecular charge-transfer (ICT) and host-induced restriction of intramolecular rotation (RIR). This new supramolecular complex with superior multicolor emission abilities may find wide applications in the fields of information processing and display media. Furthermore, the molecular design rationale presented here may provide a new design strategy for the development of high performance optical materials using a single supramolecular platform.

  • 731.
    Zhang, Xian
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Surface and Corrosion Science.
    Leygraf, Christofer
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Surface and Corrosion Science.
    Odnevall Wallinder, Inger
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Surface and Corrosion Science.
    Selected area visualization by FIB-milling for corrosion-microstructure analysis with submicron resolution2013In: Materials letters (General ed.), ISSN 0167-577X, E-ISSN 1873-4979, Vol. 98, 230-233 p.Article in journal (Refereed)
    Abstract [en]

    We report the successful use of focussed ion beam (FIB) milling of trenches in a material of complex microstructure in order to visualize a selected area (32×32 μm) for further multi-analysis with submicron resolution. This capability is demonstrated for a Zn-5 wt% Al coating Galfan™ on steel. The very same eutectic surface area was analyzed by three complementary and independent techniques providing consistent information on the lateral distribution of morphology and elemental composition (scanning electron microscopy with x-ray microanalysis, SEM/EDS), topography and Volta potential (scanning Kelvin probe force microscopy, SKPFM) and oxide composition (confocal Raman microspectroscopy, CRM). The approach enables a straightforward way to explore the interplay between microstructure and local corrosion of metallic materials.

  • 732.
    Zhang, Xian
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Surface and Corrosion Science.
    Qiu, Ping
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Surface and Corrosion Science.
    Leygraf, Christofer
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Surface and Corrosion Science.
    Odnevall Wallinder, Inger
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Surface and Corrosion Science.
    Surface structure of 55% Al-Zn alloy coating and corrosion product distribution after exposure in chloride-containing electrolytes2011In: Proceedings The 10th International Conference on the Structure of Surfaces (ICSOS-10), 2011Conference paper (Refereed)
  • 733.
    Zhang, Xian
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry.
    Vu, Thanh-Nam
    Laboratoire de Physico-chimie des Surfaces, ENSCP-CNRS, Ecole Nationale Supérieure de Chimie de Paris, Paris, France.
    Volovitch, P.
    Laboratoire de Physico-chimie des Surfaces, ENSCP-CNRS, Ecole Nationale Supérieure de Chimie de Paris, Paris, France.
    Leygraf, Christofer
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Surface and Corrosion Science.
    Ogle, K.
    Laboratoire de Physico-chimie des Surfaces, ENSCP-CNRS, Ecole Nationale Supérieure de Chimie de Paris, Paris, France.
    Odnevall Wallinder, Inger
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Surface and Corrosion Science.
    The initial release of zinc and aluminum from non-treated Galvalume and the formation of corrosion products in chloride containing media2011In: Applied Surface Science, ISSN 0169-4332, E-ISSN 1873-5584, Vol. 258, no 10, 4351-4359 p.Article in journal (Refereed)
    Abstract [en]

    This study explores the initial release of zinc and aluminum from non-treated Galvalume and the parallel formation of corrosion products when exposed to synthetic seawater and rainwater of different chloride content. Comparisons were made with long-term field exposures at non-sheltered marine conditions. Observed release rates from short-term conditions agree qualitatively with the long-term findings with a selective release of zinc over aluminum. The release and corrosion processes were intertwined through the formation of corrosion products with properties that influence the long-term release process. Prior to exposure, Al2O3 dominated the entire surface, and was subject to local destruction upon interaction with chloride ions. As a consequence Al2O3 was gradually replaced and covered by zinc-rich corrosion products primarily in interdendritic areas during the first year of marine exposure. This was followed by the gradual formation and integration of aluminum-rich corrosion products, reflected by an increased zinc release rate during the first year, followed by a gradually decreased rate during subsequent years. The importance of Al2O3 was also evident in deaerated synthetic rainwater or seawater, where the formation of Al2O3 was presumably hindered. In synthetic rain water this resulted in a higher ratio between released aluminum and zinc compared with non-deaerated conditions.

  • 734.
    Zhang, Yujia
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Li, Jiebing
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center. Chalmers, Sweden.
    Lindström, Mikael E.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center. Chalmers, Sweden.
    Mischnick, Petra
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology. Tech Univ Carolo Wilhelmina Braunschweig, Germany.
    Reactivity investigation of glucomannan from spruce2014In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 247, no 113-CELLArticle in journal (Other academic)
  • 735.
    Zhao, Yadong
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Li, Jiebing
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Comprehensive comparison between woody and tunicate celluloses2014In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 247, 95-CARB- p.Article in journal (Other academic)
  • 736.
    Zhao, Yadong
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Skaar, Katrine Sandnes
    Thompson, Eric
    Ray, Jessica Louise
    Li, Jiebing
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Troedsson, Christofer
    Qualitative and quantitative analysis of Ciona intestinalis gut content using polymerase chain reaction (PCR) technique2014In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 247, 283-BIOT- p.Article in journal (Other academic)
  • 737.
    Zhe, Li
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Relative influences of uncertainty in physical-chemical property data and variability in climate parameters in determining the fate of PCBs2011Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Persistent organic pollutants (POPs) present a class of substances which are of high concern due to their toxicity and ecotoxicity, long-range atmospheric transport and resistance to degradation. A combination of analytical measurement and modeling researchis a powerful means for understanding chemical fate and behavior. Among all availablemodeling approaches, multi-compartmental fugacity modeling is a common and relatively simpleway to simulate the concentrations and distributions of pollutants. This approach isalso applied hereto study a well-studiedgroup of POPs –polychlorinated biphenyls (PCBs).

    Climate changeis potentially one of the largest global environmental problems facing society today. Climate change resulting from anthropogenic activities may impact the transport, fate and exposure of POPs due to alterations in climatic and landscape properties (e.g. temperature, windspeed, precipitation etc.). Modeling studies have previously been carried out to investigate their influence on POPs fate under defined scenarios.However, in previous work the uncertainty of chemical properties has not been considered. We hypothesize that the uncertainties in physical-chemical parameters could actually cause a greater impact predicted concentrations than variability in climate parameters such as temperature, wind speed and precipitation.

    To test the hypothesis, a 4-compartment Level III fugacity model –ChemCAN spreadsheet model is used. A combination of8 climate variables, 3 physical-chemical properties and 4 degradation properties are chosen to investigate how the variability and uncertainty affect the environmental fate of 6 selected PCBs congeners. In total, 18 forecasts are createdin the investigation and outputs provided forconcentrations, distributions, total amounts, long-range transport potential indicators and persistence of the chemicals. We arbitrarily model the Japan region for which we had environmental parameterization in the ChemCAN model. Monte-Carlo simulations areundertakenusing the

    Crystal Ball®computer software to perform correlation and sensitivity analyses, in order to specifically examine andcompare the influence brought from variability and uncertainty.Datafor climate variablesarecollected and calculated from Intergovernmental Panel on Climate Change –Data Distribution Centre (IPCC-DDC), while thosefor chemical propertyuncertainty arecollected and calculated from literature sources/methods.

    The results are interpreted focusing on the two types of analyses –correlation and sensitivity. Within the correlation analysis between climate variables and PCB fate predictions, temperature is the most important factor affecting total amount, concentrations and distributions, especially in the atmosphere compartment. It alsoinfluencesthefugacity of the PCBs in each media, as well asthe reactive residence times. The uncertainty of temperature increases resulting fromclimate change has more influence thanvariability in mean temperature however. Precipitation hardly has any influence onPCB fate,althoughthe change in precipitationdue to climate changecould affect distributions in surface water and surface soil for light chlorinated PCBs congeners due to the extremely high coefficient of variation. Wind speedalso has little impact onpredictions other than for long-range transport potential descriptors, namely characteristic transport distance and transfer efficiency. Wind speed also affectsthe advective residence timein theair compartment forPCBs.Within the correlation analysis between properties and PCB fate predictions, all the chosen 3 physical-chemical properties, vapor pressure, water solubility and water-octanol partition coefficient, significantly affect the predictions. Vapor pressure has more influence onpredictions related to air and more significantly on lighter PCBs, while water solubility and the water-octanol partition coefficient mostly affect the heavier PCBs, especially

    MSc. Thesis in Environmental Chemistry

    II

    the predicted outcomes in water and sediment. Despite a fairly small uncertainty inphysical-chemical propertiescompared to many other chemicals, the influence on PCB fate is noticeable. Degradation properties, which have a rather high uncertainty, also significantly affect PCB environmental fate and degradation half-lives in air and soil have much more significant influence than those in water and sediment.

    In the sensitivity analysis, variability and uncertainty are assembled into a single simulation. When excluding degradation properties, it could be concluded that uncertainty inphysical-chemical properties is usually dominant forPCBs. One notable exception isthat precipitation change has a greaterinfluence on PCB-8, which is also the lightestincluded inthe study. If degradation propertiesare included, degradation half-lives in air and soil are always the dominantsource of uncertainty to predictions.

    The main conclusion of this thesis is that the uncertainty in chemical property datais generally more important than variability in climate parameters in controlling variance in predicted environmental concentrations.This supports the hypothesis of that was raised at the beginning of this study.

     

     

  • 738.
    Zhou, Juan
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry.
    Butchosa, Nuria
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Jayawardena, H. Surangi N.
    Zhou, Qi
    KTH, School of Biotechnology (BIO), Glycoscience. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Yan, Mingdi
    KTH, School of Chemical Science and Engineering (CHE), Chemistry.
    Ramström, Olof
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Glycan-Functionalized Fluorescent Chitin Nanocrystals for Biorecognition Applications2014In: Bioconjugate chemistry, ISSN 1043-1802, E-ISSN 1520-4812, Vol. 25, no 4, 640-643 p.Article in journal (Refereed)
    Abstract [en]

    A new platform based on chitin nanocrystals has been developed for biorecognition applications. TEMPO-oxidized chitin nanocrystals (TCNs) were labeled with a fluorescent imidazoisoquinolinone dye, and simultaneously conjugated with carbohydrate ligands, resulting in dually functionalized TCNs. The biorecognition properties of the nanocrystals were probed with lectins and bacteria, resulting in selective interactions with their corresponding cognate carbohydrate-binding proteins, as visualized by optical, fluorescence, STEM, and TEM imaging. This represents a new approach to multifunctional nanomaterials based on naturally occurring polymers, holding high potential for biomedical applications.

  • 739.
    Zhou, Qi
    et al.
    KTH, School of Biotechnology (BIO), Glycoscience. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Butchosa, Núria
    KTH, School of Biotechnology (BIO), Glycoscience.
    Nanocellulose-based Green Nanocomposite Materials2016In: Biodegradable Green Composites, John Wiley & Sons, 2016, 118-148 p.Chapter in book (Refereed)
  • 740. Zhou, Xu
    et al.
    Li, Fei
    Li, Hua
    Zhang, Biaobiao
    Yu, Fengshou
    Sun, Licheng
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Organic Chemistry.
    Photocatalytic Water Oxidation by Molecular Assemblies Based on Cobalt Catalysts2014In: ChemSusChem, ISSN 1864-5631, E-ISSN 1864-564X, Vol. 7, no 9, 2453-2456 p.Article in journal (Refereed)
    Abstract [en]

    Chromophore-catalyst molecular assemblies towards visible light-driven water oxidation were synthesized by covalent integration of a light-harvesting complex [Ru(bpy)(3)](2+) (bpy= 2,2'-bipyridine) and a Co4O4 cubane water oxidation catalyst. The two components were assembled either in linear or macrocyclic configurations. In the presence of the sacrificial reagent, the Ru-Co metallocycle exhibits remarkable photocatalytic activity for oxygen evolution, which is one order of magnitude higher than that of a multicomponent system and exceeds that of a linear assembly by a factor of five, offering access to highly active photocatalyst through molecular design.

  • 741.
    Zhu, Binzhu
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemical Engineering and Technology, Chemical Reaction Engineering.
    Mellander, B. -E
    Fluoride-based electrolytes and their applications for intermediate temperature ceramic fuel cells2005In: Fluorinated Materials for Energy Conversion, Elsevier, 2005, 419-437 p.Chapter in book (Other academic)
    Abstract [en]

    This chapter focuses on fluoride-based electrolytes and their applications for intermediate temperature ceramic fuel cells. Among all fuel cell (FC) technologies, the solid oxide fuel cell (SOFC) can utilize a number of different fuels. The conventional SOFCs use a ceramic electrolyte, e.g., yttria-stabilized zirconia (YSZ), and operate at high temperature, typically 1000°C. The high operating temperature puts very high demands on the materials and technology, which poses a major challenge for the further development of SOFCs into the market. For developing cost-effective SOFCs, much effort has been devoted to obtain a lower operating temperature. All these efforts have, however, limitations due to the deficiency of technology and the stability of the material. Ceramic fuel cells (CFCs) are sometimes used as a more general term for fuel cells based on ceramic materials, which have the desired properties. In the chapter, the focus is on possible proton and oxygen ion conduction in fluoride-based electrolytes that may be of interest for fundamental and applied research. Also, the focus is to develop new advanced CFCs for intermediate temperatures.

  • 742.
    Zhu, Hongli
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Li, Yuanyuan
    Pettersson, Bert
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Fibre Technology.
    Zhang, Liming
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology.
    Lindström, Mikael
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology.
    Henriksson, Gunnar
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology.
    Technical soda lignin dissolved in urea as an environmental friendly binder in wood fiberboard2014In: Journal of Adhesion Science and Technology, ISSN 0169-4243, E-ISSN 1568-5616, Vol. 28, no 5, 490-498 p.Article in journal (Refereed)
    Abstract [en]

    The application of lignin as binder in wood composite panel is not only environmentally friendly but also commercially attractive. The dissolving of technical soda lignin is the most premier challenge in its application. In this study, the effect of different key factors on soda lignin solubility in urea was investigated. The maximum solubility of 60.16g/L was obtained under the temperature 70 degrees C, urea concentration 8M, lignin content 7%, and pH 8.8. Then, different kinds of wood fiber material were mixed with the dissolved lignin solution to make fiber board separately. The results showed that the lignin can enhance the tensile strength of particleboard and can be used as a binder in wood material, but the strength will be different with different materials. The optimal tensile strength obtained was 44.63MPa with the sample made from oriented cotton linter sheet.

  • 743.
    Zhu, Jiefang
    Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Structural Chemistry.
    Photocatalysts for Hydrogen Production2015In: Advanced Materials For Clean Energy / [ed] Xu, Q; Kobayashi, T, CRC PRESS-TAYLOR & FRANCIS GROUP , 2015, 391-419 p.Chapter in book (Refereed)
  • 744.
    Álvarez Asencio, Rubén
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Surface and Corrosion Science.
    Bettini, Eleonora
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Surface and Corrosion Science.
    Pan, Jinshan
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Surface and Corrosion Science.
    Thormann, Esben
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Surface and Corrosion Science.
    Rutland, Mark
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Surface and Corrosion Science. SP Technical Research Institute of Sweden, Sweden .
    Friction Coefficient Mapping (FCM) and Contact Adhesion Mapping (CAM): Surface Microstructure and Function2013In: 5th World Tribology Congress, WTC 2013, 2013, Vol. 4, 3120-3121 p.Conference paper (Refereed)
  • 745. Álvarez-Asencio, R.
    et al.
    Wallqvist, Viveca
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Material och ytteknik.
    Kjellin, Mikael
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Life Science.
    Rutland, Mark W.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Life Science. Department of Surface and Corrosion Science, School of Chemical Science and Engineering, KTH Royal Institute of Technology.
    Camacho, A.
    Nordgren, Niklas
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Material och ytteknik.
    Luengo, G. S.
    Nanomechanical properties of human skin and introduction of a novel hair indenter2016In: Journal of The Mechanical Behavior of Biomedical Materials, ISSN 1751-6161, E-ISSN 1878-0180, Vol. 54, 185-193 p.Article in journal (Refereed)
    Abstract [en]

    The mechanical resistance of the stratum corneum, the outermost layer of skin, to deformation has been evaluated at different length scales using Atomic Force Microscopy. Nanomechanical surface mapping was first conducted using a sharp silicon tip and revealed that Young’s modulus of the stratum corneum varied over the surface with a mean value of about 0.4 GPa. Force indentation measurements showed permanent deformation of the skin surface only at high applied loads (above 4 μN). The latter effect was further demonstrated using nanomechanical imaging in which the obtained depth profiles clearly illustrate the effects of increased normal force on the elastic/plastic surface deformation. Force measurements utilizing the single hair fiber probe supported the nanoindentation results of the stratum corneum being highly elastic at the nanoscale, but revealed that the lateral scale of the deformation determines the effective elastic modulus.This result resolves the fact that the reported values in the literature vary greatly and will help to understand the biophysics of the interaction of razor cut hairs that curl back during growth and interact with the skin.

  • 746.
    Álvarez-Asencio, Rubén
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Surface and Corrosion Science. Institute for Advanced Studies, IMDEA Nanoscience, C/Faraday 9, Spain.
    Wallqvist, V.
    Kjellin, M.
    Rutland, Mark
    KTH, School of Chemical Science and Engineering (CHE), Chemistry, Surface and Corrosion Science. SP Technical Research Institute of Sweden, SP Chemistry, Materials and Surfaces, Sweden.
    Camacho, A.
    Nordgren, N.
    Luengo, G. S.
    Nanomechanical properties of human skin and introduction of a novel hair indenter2016In: Journal of The Mechanical Behavior of Biomedical Materials, ISSN 1751-6161, E-ISSN 1878-0180, Vol. 54, 185-193 p.Article in journal (Refereed)
    Abstract [en]

    The mechanical resistance of the stratum corneum, the outermost layer of skin, to deformation has been evaluated at different length scales using Atomic Force Microscopy. Nanomechanical surface mapping was first conducted using a sharp silicon tip and revealed that Young’s modulus of the stratum corneum varied over the surface with a mean value of about 0.4 GPa. Force indentation measurements showed permanent deformation of the skin surface only at high applied loads (above 4 μN). The latter effect was further demonstrated using nanomechanical imaging in which the obtained depth profiles clearly illustrate the effects of increased normal force on the elastic/plastic surface deformation. Force measurements utilizing the single hair fiber probe supported the nanoindentation results of the stratum corneum being highly elastic at the nanoscale, but revealed that the lateral scale of the deformation determines the effective elastic modulus.This result resolves the fact that the reported values in the literature vary greatly and will help to understand the biophysics of the interaction of razor cut hairs that curl back during growth and interact with the skin.

  • 747.
    Ågren, Hans
    et al.
    KTH, School of Biotechnology (BIO), Theoretical Chemistry (closed 20110512).
    Tu, Yaoquan
    KTH, School of Biotechnology (BIO), Theoretical Chemistry (closed 20110512).
    Modeling of Non-linear Optic Properties of Guest-Host Systems2006In: Nonlinear Optics, Quantum Optics: concepts in modern optics, ISSN 1543-0537, Vol. 35, no 1-3, 39-55 p.Article in journal (Refereed)
    Abstract [en]

    In this paper we summarize our recent work in computer modeling of nonlinear optical (NLO) properties of guest-host systems. The modeling involves quantum chemistry calculations to predict the NLO properties of a single chromophore molecule and molecular dynamics simulations to estimate the macroscopic NLO properties of the corresponding guest-host systems and to find the microscopic origin behind the macroscopic properties. The systems studied cover solutions solvated with NLO chromophores and amorphous polymers doped with dipolar chromophore molecules. Some gained insight and conclusions obtained from the combined modeling approaches are presented.

  • 748. Öhman, Anders
    et al.
    Lycksell, P O
    Juréus, A
    Langel, U
    Bartfai, T
    Gräslund, A
    NMR study of the conformation and localization of porcine galanin in SDS micelles. Comparison with an inactive analog and a galanin receptor antagonist.1998In: Biochemistry, ISSN 0006-2960, E-ISSN 1520-4995, Vol. 37, no 25Article in journal (Refereed)
    Abstract [en]

    Galanin is a 29/30-residue neuro-endocrine peptide which performs its many important physiological functions via a membrane-bound receptor. By using two-dimensional proton NMR spectroscopy, complete relaxation matrix analysis, and simulated annealing, the conformation of porcine galanin was determined in a membrane-mimicking solvent containing sodium dodecyl sulfate (SDS) micelles. The final family of calculated structures displays three well-defined beta- or gamma-turn regions, comprising residues 1-5, 7-10, and 24-27, but has otherwise a random conformation. The receptor-interacting N-terminal part, residues 1-5, was found to be best defined with a backbone RMSD value of 0.12 A. The mode of association between galanin and the SDS micelle was determined by observing the broadening effect on proton resonances, when spin-labeled 5- and 12-doxyl stearate molecules were added. It was concluded that galanin is located close to the surface of the micelle with two regions, residues 6-9 and 24-29, as well as two single residues, 18 and 21, reaching out into the aqueous solvent. Additional NMR studies were carried out on an inactive analogue, Ala2-galanin, and an antagonist M40. The results show that the proton resonances of galanin and M40 have identical chemical shifts in the N-terminal receptor-interacting region, indicating similar solution structures in this region. For Ala2-galanin, the same region displays a spectral heterogeneity with chemical shifts clearly different from the other two peptides, indicative of different secondary structures. These results may provide a structural background for the antagonist activity of M40 and the hormonal inactivity of Ala2-galanin, as compared to galanin.

  • 749.
    Öhman, Anders
    et al.
    Umeå University, Faculty of Medicine, Department of Pharmacology and Clinical Neuroscience.
    Rak, Alexey
    Dontsova, Maria
    Garber, Maria B
    Härd, Torleif
    NMR structure of the ribosomal protein L23 from Thermus thermophilus.2003In: Journal of Biomolecular NMR, ISSN 0925-2738, E-ISSN 1573-5001, Vol. 26, no 2Article in journal (Refereed)
    Abstract [en]

    The ribosomal protein L23 is a component of the large ribosomal subunit in which it is located close to the peptide exit tunnel. In this position L23 plays a central role both for protein secretion and folding. We have determined the solution structure of L23 from Thermus thermophilus. Uncomplexed L23 consists of a well-ordered part, with four anti-parallel beta-strands and three alpha-helices connected as beta-alpha-beta-alpha-beta-beta-alpha, and a large and flexible loop inserted between the third and fourth beta-strand. The observed topology is distantly related to previously known structures, primarily within the area of RNA biochemistry. A comparison with RNA-complexed crystal structures of L23 from T. thermophilus, Deinococcus radiodurans and Haloarcula marismourtui, shows that the conformation of the well-ordered part is very similar in the uncomplexed and complexed states. However, the flexible loop found in the uncomplexed solution structure forms a rigid extended structure in the complexed crystal structures as it interacts with rRNA and becomes part of the exit tunnel wall. Structural characteristics of importance for the interaction with rRNA and with the ribosomal protein L29, as well as the functional role of L23, are discussed.

  • 750.
    Öhman, Maria
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    An in situ spectro-electrochemical study of aluminium/polymer interfaces: development of ATR-FTIR and its integration with EIS for corrosion studies2006Licentiate thesis, comprehensive summary (Other scientific)
    Abstract [en]

    In order to extend the applications of aluminium, organic coatings may be applied on sheet materials, for instance for corrosion protection or aesthetic surface finish purposes in the automotive and construction industries, or on foil materials in the flexible packaging industry.

    The most common mechanisms for deterioration and structural failure of organically coated aluminium structures are triggered by exposures to the surrounding environment. Despite the great importance to elucidate the influence of exposure parameters on a buried aluminium/polymer interface, there is still a lack of knowledge regarding the mechanisms that destabilise the structure. It is generally believed that a detailed in situ analysis of the transport of corroding species to the buried interface, or of surface processes occurring therein, is most difficult to perform at relevant climatic and real-time conditions.

    In this work, Attenuated Total Reflection Fourier Transform Infrared Spectroscopy (ATR-FTIR) in the Kretschmann-ATR configuration was successfully applied to in situ studies of the transport of water and ionic species through polymer films to the aluminium/polymer interface upon exposure to ultra pure deionised water and to a 1 M sodium thiocyanate (NaSCN) model electrolyte. Other main processes distinguished were the formation of corrosion products on the aluminium surface and swelling of the surface-near polymer network. Hence, in situ ATR-FTIR was capable to separate deterioration-related processes from each other.

    To perform more unambiguous interpretations, a spectro-electrochemical method was also developed for in situ studies of the buried aluminium/polymer interface by integrating the ATR-FTIR technique with a complementary acting technique, Electrical Impedance Spectroscopy (EIS). While transport of water and electrolyte through the polymer film to the aluminium/polymer interface and subsequent oxidation/corrosion of aluminium could be followed by ATR-FTIR, the protective properties of the polymer as well as of processes at the aluminium surface were simultaneously studied by EIS. The integrated set-up provided complementary information of the aluminium/polymer sample investigated, with ATR-FTIR being sensitive to the surface-near region and EIS being sensitive to the whole system. While oxidation/corrosion and delamination are difficult to distinguish by EIS, oxide formation could be confirmed by ATR-FTIR. Additionally, while delamination and polymer swelling may be difficult to separate with ATR-FTIR, EIS distinguished swelling of the polymer network and also identified ultimate failure as a result of delamination.

    The capability of the integrated ATR-FTIR / EIS in situ technique was explored by studying aluminium/polymer systems of varying characteristics. Differences in water and electrolyte ingress could be monitored, as well as metal corrosion, polymer swelling and delamination.

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