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  • 1451. Thormann, Esben
    et al.
    Mizuno, Hiroyasu
    Jansson, Kjell
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK), Avdelningen för oorganisk kemi och strukturkemi.
    Hedin, Niklas
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Soledad Fernandez, M.
    Luis Arias, Jose
    Rutland, Mark W.
    Pai, Ranjith Krishna
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Bergström, Lennart
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK), Avdelningen för materialkemi.
    Embedded proteins and sacrificial bonds provide the strong adhesive properties of gastroliths2012Inngår i: NANOSCALE, ISSN 2040-3364, Vol. 4, nr 13, s. 3910-3916Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The adhesive properties of gastroliths from a freshwater crayfish (Cherax quadricarinatus) were quantified by colloidal probe atomic force microscopy (AFM) between heavily demineralized gastrolith microparticles and gastrolith substrates of different composition. Combined AFM and transmission electron microscopy studies demonstrated that the sequential detachment and large adhesion energies that characterise the adhesive behaviour of a native gastrolith substrate are dominated by sacrificial bonds between chitin fibres and between chitin fibres and CaCO3. The sacrificial bonds were shown to be strongly related to the gastrolith proteins and when the majority of these proteins were removed by ethylenediaminetetraacetic acid (EDTA), the sequential detachment disappeared and the adhesive energy was reduced by more than two orders of magnitude.

  • 1452.
    Tian, Li-Yun
    et al.
    Royal Inst Technol, Dept Mat Sci & Engn, Appl Mat Phys, SE-10044 Stockholm, Sweden.;Dalian Univ Technol, Minist Educ, Key Lab Mat Modificat Laser Ion & Electron Beams, Dalian 116024, Peoples R China..
    Ye, Li-Hua
    Chinese Acad Sci, Inst Met Res, 72 Wenhua Rd, Shenyang 110016, Peoples R China..
    Hu, Qing-Miao
    Chinese Acad Sci, Inst Met Res, 72 Wenhua Rd, Shenyang 110016, Peoples R China..
    Lu, Song
    Royal Inst Technol, Dept Mat Sci & Engn, Appl Mat Phys, SE-10044 Stockholm, Sweden..
    Zhao, Jijun
    Dalian Univ Technol, Minist Educ, Key Lab Mat Modificat Laser Ion & Electron Beams, Dalian 116024, Peoples R China..
    Vitos, Levente
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Materialteori. Royal Inst Technol, Dept Mat Sci & Engn, Appl Mat Phys, SE-10044 Stockholm, Sweden.; Div MWigner Res Ctr Phys, Res Inst Solid State Phys & Opt, POB 49, H-1525 Budapest, Hungary..
    CPA descriptions of random Cu-Au alloys in comparison with SQS approach2017Inngår i: Computational materials science, ISSN 0927-0256, E-ISSN 1879-0801, Vol. 128, s. 302-309Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The lattice constant, formation enthalpy, and elastic parameters of Cu1-xAux (0 <= x <= 1) alloys in the face centered cubic crystallographic phase are investigated by using the first-principles exact muffin-tin orbitals and plane-wave pseudopotential methods in order to explore the effect of alloying with special focus on the impact of local lattice distortion (LLD) on the above properties. The compositional disorder is treated within the framework of the coherent potential approximation (CPA) and the special quasi-random structure (SQS) scheme. Calculations based on SQS and CPA show that, while LLD lowers significantly the formation enthalpy of Cu1-xAux due to the large size mismatch between Cu and Au atoms, it has negligible influence on the lattice constants and elastic parameters. These findings confirm the reliability of CPA for computing the enthalpy changes upon isotropic and unisotropic lattice distortions in disordered alloys with sizable atomic size differences.

  • 1453.
    Tiefenauer, Raphael F.
    et al.
    ETH, Switzerland.
    Tybrandt, Klas
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik och elektroteknik. Linköpings universitet, Tekniska fakulteten. ETH, Switzerland.
    Aramesh, Morteza
    ETH, Switzerland.
    Voros, Janos
    ETH, Switzerland.
    Fast and Versatile Multiscale Patterning by Combining Template-Stripping with Nanotransfer Printing2018Inngår i: ACS Nano, ISSN 1936-0851, E-ISSN 1936-086X, Vol. 12, nr 3, s. 2514-2520Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Metal nanostructures are widely used in plasmonic and electronic applications due to their inherent properties. Often, the fabrication of such nanostructures is limited to small areas, as the processing is costly, low throughput, and comprises harsh fabrication conditions. Here, we introduce a template-stripping based nanotransfer printing method to overcome these limitations. This versatile technique enables the transfer of arbitrary thin film metal structures onto a variety of substrates, including glass, Kapton, silicon, and PDMS. Structures can range from tens of nanometers to hundreds of micrometers over a wafer scale area. The process is organic solvent-free, multilayer compatible, and only takes minutes to perform. The stability of the transferred gold structures on glass exceeds by far those fabricated by e-beam evaporation. Therefore, an adhesion layer is no longer needed, enabling a faster and cheaper fabrication as well as the production of superior nanostructures. Structures can be transferred onto curved substrates, and the technique is compatible with roll-to-roll fabrication; thus, the process is suitable for flexible and stretchable electronics.

  • 1454.
    Timpanaro, S
    et al.
    Eindhoven University of Technology, Netherlands.
    Kemerink, Martijn
    Eindhoven University of Technology, Netherlands.
    Touwslager, FJ
    Eindhoven University of Technology, Netherlands.
    De Kok, MM
    Eindhoven University of Technology, Netherlands.
    Schrader, S
    Eindhoven University of Technology, Netherlands.
    Morphology and conductivity of PEDOT/PSS films studied by scanning-tunneling microscopy2004Inngår i: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 394, nr 4-6, s. 339-343Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The influence of sorbitol on the nanometer-scale morphology of poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT/PSS) is investigated by scanning-tunneling microscopy. In all investigated films relatively well-conducting PEDOT particles are observed. with typical sizes of 10-50 nm, that are embedded in a less conductive PSS matrix. Addition of sorbitol to the casting solution is found to enhance the clustering of the PEDOT particles into larger domains. The observed morphologies are correlated to the macroscopic conductivity of the films, using an intuitive model. In addition, the morphology in the top layer of the films was found to differ substantially from the bulk morphology. (C) 2004 Elsevier B.V. All rights reserved.

  • 1455.
    Tiwari, Ashutosh
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biosensorer och bioelektronik. Linköpings universitet, Tekniska fakulteten.
    Mishra, Yogendra KumarFunctional Nanomaterials Group, Christian-Albrechts-Universität zu Kiel, Germany.Kobayashi, HisatoshiInternational Center for Materials Nanoarchitectonics, National Institute for Materials Science, Japan.Turner, AnthonyLinköpings universitet, Institutionen för fysik, kemi och biologi, Biosensorer och bioelektronik. Linköpings universitet, Tekniska fakulteten.
    Intelligent nanomaterials2016Collection/Antologi (Fagfellevurdert)
    Abstract [en]

    Overall, this book presents a detailed and comprehensive overview of the state-of-the-art development of different nanoscale intelligent materials for advanced applications. Apart from fundamental aspects of fabrication and characterization of nanomaterials, it also covers key advanced principles involved in utilization of functionalities of these nanomaterials in appropriate forms. It is very important to develop and understand the cutting-edge principles of how to utilize nanoscale intelligent features in the desired fashion. These unique nanoscopic properties can either be accessed when the nanomaterials are prepared in the appropriate form, e.g., composites, or in integrated nanodevice form for direct use as electronic sensing devices. In both cases, the nanostructure has to be appropriately prepared, carefully handled, and properly integrated into the desired application in order to efficiently access its intelligent features. These aspects are reviewed in detail in three themed sections with relevant chapters: Nanomaterials, Fabrication and Biomedical Applications; Nanomaterials for Energy, Electronics, and Biosensing; Smart Nanocomposites, Fabrication, and Applications.

  • 1456. Tondi, Gianluca
    et al.
    Johansson, Mats
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik. SP Tecnical Research Institute of Sweden, Stockholm, Sweden .
    Leijonmarck, Simon
    KTH, Skolan för kemivetenskap (CHE), Kemiteknik, Tillämpad elektrokemi. KTH, Skolan för kemivetenskap (CHE), Centra, Wallenberg Wood Science Center.
    Trey, Stacy
    KTH, Skolan för kemivetenskap (CHE), Centra, Wallenberg Wood Science Center. SP Tecnical Research Institute of Sweden, Stockholm, Sweden .
    Tannin based foams modified to be semi-conductive: Synthesis and characterization2015Inngår i: Progress in organic coatings, ISSN 0300-9440, E-ISSN 1873-331X, Vol. 78, s. 488-493Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The objective of this study was to modify highly insulative and lightweight biorenewable foam thermosets to be semi-conductive for primarily building material applications. The foams were formed and then posttreated with in-situ polymerization of polyaniline, both doped and undoped, adsorbing and possibly absorbing (observed by SEM-EDX) to the foam structure at levels of 100-120 wt%. The modified tannin foams were shown to be semi-conductive in comparison to the highly insulative structure prior to polyaniline modification. While the 50% protonated polyaniline modified foams, or doped foams, had a higher conductivity than the undoped polyaniline modified foams, the acid used in fabrication of the foams provided some degree of conductivity to the undoped PANI modified foams. Moreover, the modified foams had an increased volume of 15% after modification, were more sensitive to moisture, and the polyaniline did not affect the degradation temperature of the foams.

  • 1457.
    Topalian, Zareh
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik.
    Niklasson, Gunnar A.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik.
    Granqvist, Claes-Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik.
    Österlund, Lars
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Tekniska sektionen, Institutionen för teknikvetenskaper, Fasta tillståndets fysik.
    Spectroscopic study of the photofixation of SO2 on anatase TiO2 thin films and their oleophobic properties2012Inngår i: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 4, nr 2, s. 672-679Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Photoinduced SO2 fixation on anatase TiO2 films was studied by in situ Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS). The TiO2 films were prepared by reactive DC magnetron sputtering and were subsequently exposed to 50 ppm SO2 gas mixed in synthetic air and irradiated with UV light at substrate temperatures between 298 and 673 K. Simultaneous UV irradiation and SO2 exposure between 373 and 523 K resulted in significant sulfur (S) deposits on crystalline TiO2 films as determined by XPS, whereas amorphous films contained negligible amounts of S. At substrate temperatures above 523 K, the S deposits readily desorbed from TiO2. The oxidation state of sulfur successively changed from S4+ for SO2 adsorbed on crystalline TiO2 films at room temperature without irradiation to S6+ for films exposed to SO2 at elevated temperatures with simultaneous irradiation. In situ FTIR was used to monitor the temporal evolution of the photoinduced surface reaction products formed on the TiO2 surfaces. It is shown that band gap excitation of TiO2 results in photoinduced oxidation of SO2, which at elevated temperatures become coordinated to the TiO2 lattice through interactions with O vacancies and form sulfite and sulfate surface species. These species makes the surface acidic, which is manifested in nondetectable adherence of stearic acid to the modified surface. The modified films show good chemical stability as evidenced by sonication and repeated recycling of the films. The results suggest a new method to functionalize wide band gap oxide surfaces by means of photoinduced reactions in reactive gases at elevated substrate temperatures. In the case of anatase TiO2 in reactive SO2 gas, we here show that such functionalization yields surfaces with excellent oleophobic properties, as probed by adhesion of stearic acid.

  • 1458.
    Torrens, Mabel
    et al.
    Universitat Rovira i Virgili, Tarragona, Spain.
    Ortiz, Mayreli
    Universitat Rovira i Virgili, Tarragona, Spain.
    Turner, Anthony P.F.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biosensorer och bioelektronik. Linköpings universitet, Tekniska högskolan.
    Beni, Valerio
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biosensorer och bioelektronik. Linköpings universitet, Tekniska högskolan.
    O´Sullivan, Ciara K.
    Universitat Rovira i Virgili, Tarragona, Spain: ICREA, Barcelona, Spain.
    Controlled Zn-Mediated Grafting of Thin Layers of Bipodal Diazonium Salt on Gold and Carbon Substrates2014Inngår i: Chemistry - A European Journal, ISSN 0947-6539, E-ISSN 1521-3765Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A controlled, rapid, and potentiostat-free method has been developed for grafting the diazonium salt (3,5-bis(4-diazophenoxy)benzoic acid tetrafluoroborate (DCOOH)) on gold and carbon substrates, based on a Zn-mediated chemical dediazonation. The highly stable thin layer organic platforms obtained were characterized by cyclic voltammetry, AFM, impedance, XP, and Raman spectroscopies. A dediazonation mechanism based on radical formation is proposed. Finally, DCOOH was proved as a linker to an aminated electroactive probe.

  • 1459. Touati, Baligh
    et al.
    Gassoumi, Abdelaziz
    Dobryden, Illia
    KTH, Skolan för kemivetenskap (CHE), Kemi, Yt- och korrosionsvetenskap. Luleå Univ Technol.
    Natile, Marta Maria
    Vomiero, Alberto
    Turki, Najoua Kamoun
    Engineering of electronic and optical properties of PbS thin films via Cu doping2016Inngår i: Superlattices and Microstructures, ISSN 0749-6036, E-ISSN 1096-3677, Vol. 97, s. 519-528Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Copper-doped PbS polycrystalline thin films were deposited by chemical bath deposition by adding small amount of Cu (y(solution) = [Cu2+]/[Pb2+]) between 0.5 and 2 at%. The composition, structure, morphology, optical and electrical properties of the films were investigated by means of X-ray diffraction (XRD), Rutherford backscattering spectrometry (RBS), atomic force microscopy (AFM), scanning electron microscopy (SEM), X-ray photoemission spectroscopy (XPS), UV-visible near infrared (UV-Vis-NIR) spectrophotometry and Hall effect measurements. The XRD studies showed that the undoped films have PbS face centered cubic structure with (111) preferential orientation, while preferential orientation changes to (200) plane with increasing Cu doping concentration. The AFM and SEM measurements indicated that the film surfaces consisted of nanosized grains with pyramidal shape. Optical band gap was blue shifted from 0.72 eV to 1.69 eV with the increase in Cu doping concentration. The film obtained with the [Cu2+]/[Pb2+] ratio equal to 1.5 at% Cu showed the minimum resistivity of 0.16 Omega cm at room temperature and optimum value of optical band gap close to 1.5 eV. 1.5 at% Cu-doped PbS thin films exhibit the best optical and electrical properties, suitable for solar cells applications.

  • 1460.
    Tran, Dung
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Svensson, Gunnar
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Tai, Cheuk-Wai
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    TEM-based pair distribution function study of bimetallic nanoparticles2014Inngår i: XV International Conference on Electron Microscopy, 2014Konferansepaper (Annet vitenskapelig)
  • 1461.
    Tu, Juei-feng
    et al.
    Högskolan Väst, Institutionen för ingenjörsvetenskap, Avdelningen för avverkande och additativa tillverkningsprocesser (AAT). North Carolina State University, Department of Mechanical & Aerospace Engineering, Raleigh, United States.
    Rajule, Nilesh
    North Carolina State University, Department of Mechanical & Aerospace Engineering, Raleigh, United States.
    Liu, Yi
    North Carolina State University, Raleigh, Department of Material Science and Engineering,United States.
    Martin, James
    North Carolina State University, Department of Chemistry, Raleigh, United State.
    Nanostructure diffraction analysis of a copper/single walled carbon nanotube nanocomposite synthesized by Laser Surface Implanting2017Inngår i: Carbon, ISSN 0008-6223, E-ISSN 1873-3891, Vol. 113, s. 1-9Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A new wet process, denoted as Laser Surface Implanting (LSI), has been developed to synthesize a Copper-Single Wall Carbon NanoTube (Cu-SWCNT) metal nanocomposite by dispersing SWCNTs into molten copper, followed by rapid and non-equilibrium solidification to form the Cu-SWCNT nanocomposite such that dispersed SWCNTs could locked in positions without agglomerating into large clusters. However, the nanometer sizes of the SWCNT clusters inside this nanocomposite make it extremely difficult to obtain TEM images with discernable SWCNT clusters in the copper matrix. In this paper, TEM images and their diffraction patterns for annealed pure copper, quenched pure copper (by the same synthesis process without introducing SWCNTs), and Cu-SWCNT nanocomposite are compared. It is concluded that TEM images with discernable SWCNT clusters are rare. Therefore, diffraction patterns are better tools to identify SWCNTs within the copper matrix. The indexed diffraction patterns confirm that the copper fcc lattice is preserved. However, the Cu-SWCNT nanocomposite samples also exhibit ordered diffuse scattering, consisting of at least two polyhedra of diffuse-scattering bounded by the 110* and 200* family of reciprocal lattice planes, respectively. In addition several samples exhibit super-lattice Bragg diffraction indicative expanded unit cells. It thus appears that the SWCNTs are incorporated into the Cu matrix with precise arrangements commensurate with specific Cu lattice planes. 

  • 1462.
    Tu, Li
    et al.
    Fudan Univ, State Key Lab ASIC & Syst, SIST, Shanghai 200433, Peoples R China..
    Yuan, Sijian
    Fudan Univ, State Key Lab ASIC & Syst, SIST, Shanghai 200433, Peoples R China..
    Zhang, Huotian
    Fudan Univ, State Key Lab ASIC & Syst, SIST, Shanghai 200433, Peoples R China..
    Wang, Pengfei
    Fudan Univ, State Key Lab ASIC & Syst, SIST, Shanghai 200433, Peoples R China..
    Cui, Xiaolei
    Fudan Univ, State Key Lab ASIC & Syst, SIST, Shanghai 200433, Peoples R China..
    Wang, Jiao
    Fudan Univ, State Key Lab ASIC & Syst, SIST, Shanghai 200433, Peoples R China..
    Zhan, Yi-Qiang
    Fudan Univ, State Key Lab ASIC & Syst, SIST, Shanghai 200433, Peoples R China..
    Zheng, Li-rong
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Centra, VinnExcellence Center for Intelligence in Paper and Packaging, iPACK.
    Aerosol jet printed silver nanowire transparent electrode for flexible electronic application2018Inngår i: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 123, nr 17, artikkel-id 174905Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Aerosol jet printing technology enables fine feature deposition of electronic materials onto low-temperature, non-planar substrates without masks. In this work, silver nanowires (AgNWs) are proposed to be printed into transparent flexible electrodes using a Maskless Mesoscale Material Deposition Aerosol Jet VR printing system on a glass substrate. The influence of the most significant process parameters, including printing cycles, printing speed, and nozzle size, on the performance of AgNW electrodes was systematically studied. The morphologies of printed patterns were characterized by scanning electron microscopy, and the transmittance was evaluated using an ultraviolet-visible spectrophotometer. Under optimum conditions, high transparent AgNW electrodes with a sheet resistance of 57.68 X/sq and a linewidth of 50.9 mu m were obtained, which is an important step towards a higher performance goal for flexible electronic applications.

  • 1463. Tummala, Gopi Krishna
    et al.
    Joffre, Thomas
    Rojas, Ramiro
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi. KTH, Skolan för kemivetenskap (CHE), Centra, Wallenberg Wood Science Center.
    Persson, Cecilia
    Mihranyan, Albert
    Strain-induced stiffening of nanocellulose-reinforced poly(vinyl alcohol) hydrogels mimicking collagenous soft tissues2017Inngår i: Soft Matter, ISSN 1744-683X, E-ISSN 1744-6848, Vol. 13, nr 21, s. 3936-3945Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Soft tissues possess remarkable mechanical strength for their high water content, which is hard to mimic in synthetic materials. Here, we demonstrate how strain-induced stiffening in hydrogels plays a major role in mimicking the mechanical properties of collagenous soft tissues. In particular, nanocellulose reinforced polyvinyl alcohol (PVA) hydrogels of exceptionally high water content (90-93 wt%) are shown to exhibit collagen-like mechanical behavior typical for soft tissues. High water content and co-existence of both soft and rigid domains in the gel network are the main factors responsible for strain-induced stiffening. This observed effect due to the alignment of rigid components of the hydrogel is simulated through modeling and visualized through strain-induced birefringence experiments. Design parameters such as nanocellulose aspect ratio and solvent composition are also shown to be important to control the mechanical properties. In addition, owing to their transparency (90-95% at 550 nm) and hyperelastic properties (250-350% strain), the described hydrogels are promising materials for biomedical applications, especially in ophthalmology.

  • 1464.
    Tuominen, Mikko
    et al.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Material och ytteknik.
    Teisala, H.
    Haapanen, J.
    Aromaa, M.
    Mäkelä, J. M.
    Stepien, M.
    Saarinen, Jarkko J.
    RISE, SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor. Åbo Akademi University, Åbo, Finland .
    Toivakka, M.
    Kuusipalo, J.
    Adjustable wetting of liquid flame spray (LFS) TiO2-nanoparticle coated board: Batch-type versus roll-to-roll stimulation methods2014Inngår i: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, E-ISSN 2000-0669, Vol. 29, nr 2, s. 271-279Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Superhydrophobic nanoparticle coating was created on the surface of board using liquid flame spray (LFS). The LFS coating was carried out continuously in ambient conditions without any additional hydrophobization steps. The contact angle of water (CAW) of ZrO2, Al2O3 and TiO2 coating was adjusted reversibly from &gt;150° down to ~10-20° using different stimulation methods. From industrial point of view, the controlled surface wetting has been in focus for a long time because it defines the liquid-solid contact area, and furthermore can enhance the mechanical and chemical bonding on the interface between the liquid and the solid. The used stimulation methods included batch-type methods: artificial daylight illumination and heat treatment and roll-to-roll methods: corona, argon plasma, IR (infra red)- and UV (ultra violet)-treatments. On the contrary to batch-type methods, the adjustment and switching of wetting was done only in seconds or fraction of seconds using roll-to-roll stimulation methods. This is significant in the converting processes of board since they are usually continuous, high volume operations. In addition, the creation of microfluidic patterns on the surface of TiO2 coated board using simple photomasking and surface stimulation was demonstrated. This provides new advantages and possibilities, especially in the field of intelligent printing. Limited durability and poor repellency against low surface tension liquids are presently the main limitations of LFS coatings.

  • 1465.
    Tuominen, Mikko
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Material och ytteknik.
    Teisala, H.
    Haapanen, J.
    Mäkelä, J. M.
    Honkanen, M.
    Vippola, M.
    Bardage, S.
    Wålinder, M. E. P.
    Swerin, Agne
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Material och ytteknik. KTH Royal Institute of Technology, Sweden.
    Superamphiphobic overhang structured coating on a biobased material2016Inngår i: Applied Surface Science, ISSN 0169-4332, E-ISSN 1873-5584, Vol. 389, s. 135-143Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A superamphiphobic coating on a biobased material shows extreme liquid repellency with static contact angles (CA) greater than 150° and roll-off angles less than 10° against water, ethylene glycol, diiodomethane and olive oil, and a CA for hexadecane greater than 130°. The coating consisting of titania nanoparticles deposited by liquid flame spray (LFS) and hydrophobized using plasma-polymerized perfluorohexane was applied to a birch hardwood. Scanning electron microscopy (SEM) imaging after sample preparation by UV laser ablation of coated areas revealed that capped structures were formed and this, together with the geometrically homogeneous wood structure, fulfilled the criteria for overhang structures to occur. The coating showed high hydrophobic durability by still being non-wetted after 500 000 water drop impacts, and this is discussed in relation to geometrical factors and wetting forces. The coating was semi-transparent with no significant coloration. A self-cleaning effect was demonstrated with both water and oil droplets. A self-cleanable, durable and highly transparent superamphiphobic coating based on a capped overhang structure has a great potential for commercial feasibility in a variety of applications, here exemplified for a biobased material.

  • 1466.
    Tuominen, Mikko
    et al.
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Material och ytteknik.
    Teisala, Hannu
    Haapanen, Janne
    Mäkelä, Jyrki M.
    Honkanen, Mari
    Vippola, Minnamari
    Bardage, Stig
    Wålinder, Magnus E.P.
    Swerin, Agne
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Material och ytteknik.
    Superamphiphobic overhang coating on a biobased material2016Inngår i: Annual Surface and Materials Chemistry Symposium and Materials for tomorrow, ASMCS 2016, November 8-10, 2016, Gothenburg, Sweden, 2016Konferansepaper (Fagfellevurdert)
  • 1467.
    Tureson, Nina
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska fakulteten.
    Van Nong, Ngo
    Tech Univ Denmark, Roskilde, Denmark.
    Fournier, Daniele
    Sorbonne Universites, Paris, France.
    Singh, Niraj
    Indian Institute Technology Mandi, India.
    Acharya, Somnath
    Indian Institute Technology Mandi, India.
    Schmidt, Susann
    Linköpings universitet, Institutionen för fysik, kemi och biologi. Linköpings universitet, Tekniska fakulteten. Ionbond Switzerland Olten, Switzerland.
    Belliard, Laurent
    University of Paris 06, France.
    Soni, Ajay
    Indian Institute Technology Mandi, India.
    Le Febvrier, Arnaud
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska fakulteten.
    Eklund, Per
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska fakulteten.
    Reduction of the thermal conductivity of the thermoelectric material ScN by Nb alloying2017Inngår i: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 122, nr 2, artikkel-id 025116Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    ScN-rich (Sc,Nb)N solid solution thin films have been studied, motivated by the promising thermoelectric properties of ScN-based materials. Cubic Sc1-xNbxN films for 0 amp;lt;= x amp;lt;= 0.25 were epitaxially grown by DC reactive magnetron sputtering on a c-plane sapphire substrate and oriented along the (111) orientation. The crystal structure, morphology, thermal conductivity, and thermoelectric and electrical properties were investigated. The ScN reference film exhibited a Seebeck coefficient of -45 mu V/K and a power factor of 6 x 10(-4) W/m K-2 at 750K. Estimated from room temperature Hall measurements, all samples exhibit a high carrier density of the order of 10(21) cm(-3). Inclusion of heavy transition metals into ScN enables the reduction in thermal conductivity by an increase in phonon scattering. The Nb inserted ScN thin films exhibited a thermal conductivity lower than the value of the ScN reference (10.5W m(-1) K-1) down to a minimum value of 2.2 Wm(-1) K-1. Insertion of Nb into ScN thus resulted in a reduction in thermal conductivity by a factor of similar to 5 due to the mass contrast in ScN, which increases the phonon scattering in the material. Published by AIP Publishing.

  • 1468.
    Tybrandt, Klas
    et al.
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik och elektroteknik. Linköpings universitet, Tekniska fakulteten. ETH, Switzerland.
    Khodagholy, Dion
    Columbia Univ, NY 10027 USA; NYU, NY 10016 USA.
    Dielacher, Bernd
    ETH, Switzerland.
    Stauffer, Flurin
    ETH, Switzerland.
    Renz, Aline F.
    ETH, Switzerland.
    Buzsaki, Gyorgy
    NYU, NY 10016 USA.
    Voros, Janos
    ETH, Switzerland.
    High-Density Stretchable Electrode Grids for Chronic Neural Recording2018Inngår i: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 30, nr 15, artikkel-id 1706520Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Electrical interfacing with neural tissue is key to advancing diagnosis and therapies for neurological disorders, as well as providing detailed information about neural signals. A challenge for creating long-term stable interfaces between electronics and neural tissue is the huge mechanical mismatch between the systems. So far, materials and fabrication processes have restricted the development of soft electrode grids able to combine high performance, long-term stability, and high electrode density, aspects all essential for neural interfacing. Here, this challenge is addressed by developing a soft, high-density, stretchable electrode grid based on an inert, high-performance composite material comprising gold-coated titanium dioxide nanowires embedded in a silicone matrix. The developed grid can resolve high spatiotemporal neural signals from the surface of the cortex in freely moving rats with stable neural recording quality and preserved electrode signal coherence during 3 months of implantation. Due to its flexible and stretchable nature, it is possible to minimize the size of the craniotomy required for placement, further reducing the level of invasiveness. The material and device technology presented herein have potential for a wide range of emerging biomedical applications.

  • 1469.
    Tyrala, Krzysztof
    et al.
    Institute of Physics, Jan Kochanowski University.
    Wojtaszek, Klaudia
    Institute of Physics, Jan Kochanowski University.
    Pajek, Marek
    Institute of Physics, Jan Kochanowski University.
    Kayser, Yves
    Physikalisch-Technische Bundesanstalt (PTB).
    Milne, Christopher
    Paul Scherrer Institute.
    Sá, Jacinto
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Fysikalisk kemi. Institute of Physical Chemistry, Polish Academy of Sciences.
    Szlachetko, Jakub
    Institute of Physics, Jan Kochanowski University; Institute of Physical Chemistry, Polish Academy of Sciences.
    State-Population Narrowing Effect in Two-Photon Absorption for Intense Hard X-ray Pulses2017Inngår i: Applied Sciences: APPS, ISSN 1454-5101, E-ISSN 1454-5101, Vol. 7, nr 7, artikkel-id 653Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We report on studies of state-populations during the two-photon absorption process using intense X-ray pulses. The calculations were performed in a time-dependent manner using a simple three-level model expressed by coupled rate equations. We show that the proposed approach describes well the measured rates of X-rays excited in the one-photon and two-photon absorption processes, and allows detailed investigation of the state population dynamics during the course of the incident X-ray pulse. Finally, we demonstrate that the nonlinear interaction of X-ray pulses with atoms leads to a time-narrowing of state populations. This narrowing-effect is attributed to a quadratic incidence X-ray intensity dependence characteristic for nonlinear interactions of photons with matter.

  • 1470.
    Tyutyunnik, A P
    et al.
    Institute of Solid State Chemistry, Russian Academy of Science, Ekaterinburg, Russia.
    Grins, Jekab
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Svensson, Gunnar
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Phases in the Mn-Nb-N-O system, formed by ammonolysis of mixtures of Mn acetate tetrahydrate and a Nb xerogel1998Inngår i: Materials research bulletin, ISSN 0025-5408, E-ISSN 1873-4227, Vol. 33, nr 7, s. 1035-1044Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Phase formation in the system Mn-Nb-O-N has been studied by ammonolysis of mixtures of Mn acetate tetrahydrate and an Nb xerogel at 600-900 degrees C. Observed phases were characterized by powder X-ray diffraction, scanning and transmission electron microscopy, combustion analysis, and thermogravimetric analysis. An Nb4N5-related phase, with a metal content of less than or equal to 15 at% Mn, was obtained pure at 650-700 degrees C. A new hexagonal phase MnNb2(N,O)(3) was obtained at 750-900 degrees C, Its structure is related to, but not isotypic with, that of Nb5N6. In addition, the preparations contained cubic NaCl-type (Mn, Nb)(N,O) phases. The Mn-free Nb4-y(N,O)(5) and Nb5-y(N,O)(6) (y signifying metal vacancies), with Nb4N5- and Nb5N6-type structures, respectively, were synthesized, to make possible structural comparisons with the Mn-containing phases. A black trigonal phase Mn-3.66(6)Nb-2.34(6)(O,N)(9) with a structure closely related to that of Mn4Nb2O9 was obtained at 700 degrees C. (C) 1998 Elsevier Science Ltd.

  • 1471.
    Tyutyunnik, A P
    et al.
    Institute of Solid State Chemistry, Russian Academy of Science, Ekaterinburg, Russia.
    Grins, Jekab
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Svensson, Gunnar
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Rietveld refinement studies of Nb4N5- and Nb5N6-related phases in the (Mn)-Nb-O-N system1998Inngår i: Journal of Alloys and Compounds, ISSN 0925-8388, E-ISSN 1873-4669, Vol. 278, nr 1-2, s. 83-91Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The structures of two Nb and two Mn–Nb (oxy)nitrides have been refined from Cu Kα1 powder diffractometer data by the Rietveld method and have been characterised by electron diffraction. The phases Nb3.49N4.56O0.44 and Mn0.54Nb3.07N4.40O0.60 have structures related to that of Nb4N5, an NaCl type with ordered metal vacancies. Refinements in space group I4/m, with RF=1.3% and 1.1%, respectively, have shown that they are disordered and that metal atoms partially occupy both the nominally filled 8h position and the nominally empty 2a position in the Nb4N5 type. The observed bond lengths indicate that the 2a position is occupied only by Mn atoms in Mn0.54Nb3.07N4.40O0.60. The Nb5N6 type structure of Nb5(N,O)6 and the related structure of MnNb2(N,O)3 has been refined in space group P63/mcm to RF=1.5% and 2.9%, respectively. In the latter, the trigonal prism sites 6g are found to be occupied only by Nb, the octahedral 4d sites by approximately equal amounts Mn and Nb and the octahedral 2a site, empty in the Nb5N6 type structure, only by Mn. The Nb (oxy)nitride structures exhibit short Nb–Nb distances which indicates localised bonding between Nb atoms. Magnetic susceptibility and electrical conductivity measurements of the tetragonal phases at 15–300 K show, respectively, small magnetic moments which are coupled in an antiferromagnetic manner at low temperatures and poor, nearly temperature-independent, conductivities.

  • 1472. Tyutyunnik, A P
    et al.
    Zubkov, V G
    Kellerman, D G
    Pereliaev, V A
    Karkin, A E
    Svensson, Gunnar
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Synthesis, superconducting properties and structural (including electron diffraction) studies of Na chi NbO2 and Li chi NbO21996Inngår i: European Journal of Solid State and Inorganic Chemistry, ISSN 0992-4361, E-ISSN 1873-3751, Vol. 33, s. 53-65Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Monophasic NaxNbO2 (x = 0.5 - 0.6), T-c approximate to 4.1 K was prepared by solid state reaction between Na3NbO4 and Nb. X-ray powder diffraction data from a monophasic sample were used for a refinement of the structure of Na0.5NbO2 (R(p) = 7.4 % and R(I) = 5.3 %), using the Rietveld method. At low x-values a closely related second phase can occur. Rietveld refinement using X-ray powder diffraction data showed this phase to be isostructural with NaNbO2 but with the chemical formula Na0.1NbO2. Transmission electron microscopy studies of NaxNbO2 and LixNbO2 revealed the presence of superstructures in some crystallites. The electron diffraction patterns resemble to some extent those reported for transformations among tantalum chalcogenides.

  • 1473.
    Törndahl, Tobias
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för materialkemi.
    Ottosson, Mikael
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för materialkemi.
    Carlsson, Jan-Otto
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för materialkemi.
    Growth of Copper(I) Nitride by ALD Using Copper(II) Hexafluoroacetylacetonate, Water, and Ammonia as Precursors2006Inngår i: Journal of the Electrochemical Society, ISSN 0013-4651, E-ISSN 1945-7111, Vol. 153, nr 3, s. C146-C151Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Films of copper(I) nitride were deposited by atomic layer deposition ALD using copper(II) hexafluoroacetylacetonate, water, and ammonia as precursors. Introduction of a water pulse in the ALD cycle was found to be crucial for initiating film growth on both amorphous SiO2 and single-crystalline α-Al2O3(001) substrates. The water pulses generated an oxidic copper monolayer, which in a subsequent ammonia pulse was converted to the nitride. The films have been grown in the temperature range from 210 to 302°C. Phase pure films of Cu3N were obtained up to 265°C. At higher deposition temperatures such as 283°C, phase mixtures of Cu3N and Cu were obtained. For temperatures above 302°C films of only Cu were grown. Film growth rate was the same on the two different substrates. The films were randomly oriented on SiO2. Completely intact films were obtained at a thickness of 20 nm. The optical bandgap of the films was measured to be 1.6 eV.

  • 1474.
    Uheida, Abdusalam
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Selective Separation of Metal Ions by Solvent Extraction, Liquid Membranes and Magnetic Nanoparticles2006Doktoravhandling, med artikler (Annet vitenskapelig)
  • 1475.
    Uheida, Abdusalam
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Iglesias, Monica
    Fontas, Claudia
    Hidalgo, Manuela
    Salvado, Victoria
    Zhang, Yu
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    Muhammed, Mamoun
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Sorption of palladium(II), rhodium(III), and platinum(IV) on Fe3O4 nanoparticles2006Inngår i: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 301, nr 2, s. 402-408Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The adsorption of palladium(II), rhodium(III), and platinum(IV) from diluted hydrochloric acid solutions onto Fe3O4 nanoparticles has been investigated. The parameters studied include the contact time and the concentrations of metals and other solutes such as H+ and chloride. The equilibrium time was reached in less than 20 min for all metals. The maximum loading capacity of Fe3O4 nanoparticles for Pd(II), Rh(III), and Pt(IV) was determined to be 0.103, 0.149, and 0.068 mmol g(-1), respectively. A sorption mechanism for Pd(II), Rh(III), and Pt(IV) has been proposed and their conditional adsorption equilibrium constants have been determined to be log K = 1.72, 1.69, and 1.84, respectively. Different compositions of eluting solution were tested for the recovery of Pt(IV), Pd(II), and Rh(III) from Fe3O4 nanoparticles. It was found that 0.5 mol L-1 HNO3 can elute all of the metal ions simultaneously, while 1 mol L-1 NaHSO3 was an effective eluting solution for Rh(III), and 0.5 mol L-1 NaClO4 for Pt(IV). In competitive adsorption, the nanoparticles showed stronger affinity for Rh(III) than for Pd(II) and Pt(IV).

  • 1476.
    Uheida, Abdusalam
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Iglesias, Mònica
    Fontàs, Claudia
    Zhang, Yu
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    Muhammed, Mamoun
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Adsorption Behavior of Platinum Group Metals (Pd, Pt, Rh) onNonylthiourea-Coated Fe3O4 Nanoparticles2006Inngår i: Separation science and technology (Print), ISSN 0149-6395, E-ISSN 1520-5754, Vol. 41, s. 909-923Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Magnetite nanoparticles coated with nonylthiourea (NTH) were synthesizedand analyzed for the separation and recovery of platinum group metals (PGMs) fromdiluted aqueous chloride solutions. Physical characterizations of the coated nanoparticleswere performed by Transmission Electron Microscopy (TEM), ThermogravimetricAnalysis (TGA) and FT-IR Spectrometry. Separation efficiency of the coatednanoparticles and the equilibrium adsorption isotherm of PGMs were investigated.The maximum adsorption was attained in less than 30 minutes, and the maximumloading capacity of NTH-coated Fe3O4 nanoparticles for Pt(IV) and Pd(II) was determinedto be 10.7 and 8.1 mg g21, respectively. The recovery of PGMs from the loadednanoparticles was examined using different eluting solutions, including HNO3,thiourea, and NaClO4.

  • 1477.
    Uheida, Abdusalam
    et al.
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Salazar-Alvarez, German
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Bjorkman, Eva
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    Zhang, Yu
    KTH, Skolan för kemivetenskap (CHE), Kemi.
    Muhammed, Mamoun
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Fe3O4 and gamma-Fe2O3 nanoparticles for the adsorption of Co2+ from aqueous solution2006Inngår i: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 298, nr 2, s. 501-507Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The adsorption of Co2+ ions from nitrate solutions using iron oxide nanoparticles of magnetite (Fe3O4) and maghemite (gamma-Fe2O3) has been studied. The adsorption of Co2+ ions on the surface of the particles was investigated under different conditions of oxide content, contact time, Solution pH. and initial Co2+ ion concentration. It has been found that the equilibrium can be attained in less than 5 ruin. The maximum loading capacity of Fe3O4 and gamma-Fe2O3 nanoparticles is 5.8 x 10(-5) and 3.7 x 10(-5) mol m(-2), respectively, which are much higher than the previously Studied. iron oxides and conventional ion exchange resins. Co2+ ions were also recovered by dilute nitric acid from the loaded gamma-Fe2O3 and Fe3O4 with an efficiency of 86 and 30%. respectively. That has been explained by the different mechanisms by including both the surface and Structural loadings of Co2+ ions. The Surface adsorption of Co2+ on Fe3O4 and gamma-Fe2O3 nanoparticles has been found to have the same mechanism of ion exchange reaction between Co2+ in the solution and proton bonded on the particle Surface. The conditional equilibrium constants of surface 2-adsorption of Co2+ on Fe3O4 and gamma-Fe-O-2(3) nanoparticles have been determined to be log K = -3.3 +/- 0.3 and -3.1 +/- 0.2, respectively. The Structural loading of Co2+ ions into Fe3O4 lattice has been found to be the ion exchange reaction between CO2+ and Fe2+ while that into gamma-Fe2O3 lattice to fill its vacancy. The effect of temperature on the adsorption of Co2+ was also investigated, and the value of enthalpy change was determined to be 19 kJ mol(-1)

  • 1478.
    Uheida, Abdusalam
    et al.
    KTH, Tidigare Institutioner                               , Materialvetenskap.
    Zhang, Yu
    KTH, Tidigare Institutioner                               , Kemi.
    Muhammed, Mamoun
    KTH, Tidigare Institutioner                               , Materialvetenskap.
    Extraction of platinum(IV) with nonylthiourea dissolved in chloroform from hydrochloric acid media2003Inngår i: Solvent extraction and ion exchange, ISSN 0736-6299, E-ISSN 1532-2262, Vol. 21, nr 6, s. 827-840Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The extractant nonylthiourea (NTH) in chloroform has been investigated for the extraction of Pt(IV) from chloride solutions at ionic strength of I = 4.0 M and at 22degreesC. It has been found that chloride concentration has a negative effect on the extraction equilibrium, while proton concentration has no effect. The numerical analysis of the equilibrium data has shown that the extraction of PtCl62- with NTH can be interpreted by the formation Of PtCl4(NTH) and PtCl4(NTH)(4) species with their respective equilibrium constants of log K-11 = 5.06 +/- 0.01 and log K-14 = 14.12 +/- 0.04 in 4 M HCl. FTIR spectra of the free NTH and the NTH-Pt(IV) complex were studied to obtain some information on the interaction between Pt(IV) ions and NTH molecules.

  • 1479.
    Uheida, Abdusalam
    et al.
    KTH, Tidigare Institutioner                               , Materialvetenskap.
    Zhang, Yu
    KTH, Tidigare Institutioner                               , Kemi.
    Muhammed, Mamoun
    KTH, Tidigare Institutioner                               , Materialvetenskap.
    Selective extraction of palladium(II) from chloride solutions with nonylthiourea dissolved in chloroform2002Inngår i: Solvent extraction and ion exchange, ISSN 0736-6299, E-ISSN 1532-2262, Vol. 20, nr 6, s. 717-733Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The extraction of Palladium(II) [Pd(II)] from hydrochloric acid solutions with nonylthiourea (NTH) dissolved in chloroform at a constant ionic strength of LOM has been studied. The extraction of Pd(II) has been investigated as a function of the concentration of the extractant, chloride ion, and proton concentrations as well as extraction temperature. The distribution data have been treated graphically and numerically. The analysis of the experimental data has shown that Pd(II) is extracted as PdCl2 . (NTH) and PdCl2 . (NTH)(2) species with the respective extraction constants of log K-11 = 5.0 +/- 0.1 and log K-12 = 9.1 +/- 0.1. The back-extraction of Pd(II) from the organic phase using different stripping reagents has been examined. The selectivity of NTH for Pd(II) against Pt(IV), Rb(III), Cu(II), Fe(III), and Zn(II) has also been investigated.

  • 1480.
    Uheida, Abdusalam
    et al.
    KTH, Tidigare Institutioner, Materialvetenskap.
    Zhang, Yu
    KTH, Tidigare Institutioner, Materialvetenskap.
    Muhammed, Mamoun
    KTH, Tidigare Institutioner, Materialvetenskap.
    Thermodynamic modeling of extraction equilibria of platinum and palladium with nonylthiourea from hydrochloric acid media2004Inngår i: Separation science and technology (Print), ISSN 0149-6395, E-ISSN 1520-5754, Vol. 39, nr 15, s. 3665-3677Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Models of extraction equilibria of Pt(IV) and Pd(II) with Nonylthiourea (NTH) from HCl media have been studied. The conditional equilibrium constants and the stoichiometry of the extracted species of Pt(IV) with NTH at different ionic strengths obtained by numerical analysis using the LETAGROP-DISTR program are reported. The dependence of the extraction constant values on the ionic strength has been analysed using the Specific Interaction Theory (SIT), from which the respective thermodynamic equilibrium constants of the extraction of Pt(IV) and Pd(II) with NTH have been determined. The thermodynamic equilibrium constants determined for Pt(IV) are log K-11o=5+/-1 and log K-14(o)=14.6+/-0.2, while for Pd(II) log K-11(o)=4.9+/-0.1 and log K-12(o)=9.17+/-0.08. The interaction coefficients, epsilon, for the pairs (H+, PtCl62-) and (H+, PdCl42-) have also been estimated to be 0.30+/-0.08 and 0.41+/-0.02, respectively.

  • 1481.
    Uheida, Abdusalam
    et al.
    KTH, Tidigare Institutioner, Materialvetenskap.
    Zhang, Yu
    KTH, Tidigare Institutioner, Kemi.
    Muhammed, Mamoun
    KTH, Tidigare Institutioner, Materialvetenskap.
    Transport of palladium(II) through hollow fiber supported liquid membrane facilitated by nonylthiourea2004Inngår i: Journal of Membrane Science, ISSN 0376-7388, E-ISSN 1873-3123, Vol. 241, nr 2, s. 289-295Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The facilitated transport of Pd(II) from chloride media has been investigated through a hollow-fiber supported liquid membrane using nonylthiourea (NTH) as a carrier. The influence of the chemical conditions on the permeability of Pd(II) is reported. A model is presented that describes the transport mechanism, consisting of diffusion through a feed aqueous diffusion layer, a fast interfacial chemical reaction, and diffusion of carrier and its metal complex through the organic membrane. The diffusion resistances through organic membrane (Delta(org)) and through aqueous layer (Delta(aq)), respectively, have been calculated from the proposed model. The permeability of Pd(II) seems to be governed by the diffusion of Pd(II) species through the hollow fiber supported liquid membrane with PdCl2(NTH)(2) as a predominant carrier and PdCl2(NTH)to a lesser extent, though both have similar diffusion coefficients.

  • 1482.
    Ukleev, V.
    et al.
    BP Konstantinov Petersburg Nucl Phys Inst, Kurchatov Inst, Natl Res Ctr, Gatchina 188300, Russia.;RIKEN, Ctr Emergent Matter Sci, Wako, Saitama 3510198, Japan..
    Khassanov, A.
    Friedrich Alexander Univ Erlangen Nurnberg, Dept Mat Sci, Inst Polymer Mat, Martensstr 7, D-91058 Erlangen, Germany..
    Snigireva, I.
    European Synchrotron Radiat Facil, 71 Ave Martyrs,CS40220, F-38043 Grenoble 9, France..
    Konovalov, O.
    European Synchrotron Radiat Facil, 71 Ave Martyrs,CS40220, F-38043 Grenoble 9, France..
    Dudnik, M.
    BP Konstantinov Petersburg Nucl Phys Inst, Kurchatov Inst, Natl Res Ctr, Gatchina 188300, Russia..
    Dubitskiy, I.
    BP Konstantinov Petersburg Nucl Phys Inst, Kurchatov Inst, Natl Res Ctr, Gatchina 188300, Russia..
    Vorobiev, Alexei
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Materialfysik. European Synchrotron Radiat Facil, 71 Ave Martyrs,CS40220, F-38043 Grenoble 9, France.
    Self-assembly of a binary mixture of iron oxide nanoparticles in Langmuir film: X-ray scattering study2017Inngår i: Materials Chemistry and Physics, ISSN 0254-0584, E-ISSN 1879-3312, Vol. 202, s. 31-39Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In present study we exploited Langmuir technique to produce self-assembled arrays composed of monodisperse iron oxide nanoparticles 10 nm and 20 nm in diameter and of their binary mixture. A combination of in-situ X-ray reflectometry and Grazing-incident small-Angle X-ray scattering was used to obtain in-plane and out-of-plane structure of the arrays directly on the water surface. Surface pressure isotherms and X-ray reflectometry analysis showed that monodisperse 10 nm nanoparticles form a highly ordered monolayer, while 20 nm particles pack in three-dimensional clusters with a short-range (nearest-neighbor) correlations between the particles. In a binary mixture of 10 nm and 20 nm nano particles composed in proportion 3:1 the self-assembly process results in a structure where the monolayer of 10 nm particles is perturbed by the larger particles. Non-trivial mixing causes an enlargement of interparticle distance but keeps the symmetry of two-dimensional lattice of smaller nanoparticles. Estimation of the acting interactions and micromagnetic simulation suggest the optimal formation for monodisperse and binary ensembles.

  • 1483. Unal, B.
    et al.
    Durmus, Z.
    Kavas, H.
    Baykal, A.
    Toprak, Muhammet
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Materialfysik, Funktionella material, FNM.
    Synthesis, conductivity and dielectric characterization of salicylic acid-Fe3O4 nanocomposite2010Inngår i: Materials Chemistry and Physics, ISSN 0254-0584, E-ISSN 1879-3312, Vol. 123, nr 1, s. 184-190Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We report on the synthesis of water dispersible salicylic acid -Fe3O4 nanocomposites via a co-precipitation route by using Fe(III) and Fe(II) chloride salts, and salicylic acid. Crystalline phase was identified as Fe3O4 and the crystallite size was obtained as 13 +/- 6 nm from X-ray line profile fitting. As compared to the particle size of 20 nm obtained from TEM analysis these particles show polycrystalline nature. The capping of salicylic acid around Fe3O4 nanoparticles was confirmed by FTIR spectroscopy, the interaction being via bridging oxygens of the carboxylate and the nanoparticle surface. ac and dc conductivity measurements performed on the nanocomposite revealed semiconductor characteristics and varying trends with temperature due to reorganization of the nanocomposite. Permittivity measurements showed increasing dielectric constant with increasing temperature as expected from semiconductors. Analysis of electrical modulus and dielectric permittivity functions suggest that ionic and polymer segmental motions are strongly coupled in the nanocomposite. (C) 2010 Elsevier B.V. All rights reserved.

  • 1484.
    Utsel, Simon
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Fiberteknologi. KTH, Skolan för teknikvetenskap (SCI), Centra, VinnExcellens Centrum BiMaC Innovation.
    Surface Modification of Cellulose-based Materials for Tailoring of Interfacial Interactions2012Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The awareness of our need for a sustainable society has encouraged the search for renewable, high quality materials that can replace oil-based products. This, in combination with increased competition in the forest industry, has stimulated a lot of research into different types of wood-based materials where cellulose-rich fibers are combined with different types of polymers. There is hence a great need to develop efficient fiber modification techniques by which the fibers can be tailored to obtain specific properties. A significant change in properties can be achieved by modifying only the surface of fibers although only a relatively small amount of the total fiber material is modified. In this thesis, several surface modification techniques are presented as new tools to design the properties of different cellulose-based materials.

    In paper I, thermoresponsive nanocomposites have been assembled from specially designed thermoresponsive block copolymers and nanofibrillated cellulose. The block copolymers have one thermoresponsive block and one cationically charged block which can thus attach the polymer to an oppositely charged fiber/fibril surface. Multilayers were assembled with these block copolymers and nanofibrillated cellulose (NFC) utilizing the Layer-by-Layer (LbL) technique, resulting in thin films with a thermoresponsive behavior.

    In papers II and III, amphiphilic block copolymers with one less polar high molecular weight block and one cationic block were synthesized for use as a compatibilizer between fibers/fibrils and less polar polymer matrices in composites. The less polar block consisted of polystyrene (PS) in paper II and poly(ɛ-caprolactone) (PCL) in paper III. These polymers self-assemble into cationic micelles in water which can adsorb to oppositely charged surfaces, such as cellulose-based fibers/fibrils, in water under mild conditions and decrease the surface energy of the surface. Atomic force microscopy (AFM) was used to evaluate the adhesive properties of surfaces treated with these compatibilizers which clearly showed the formation of physical entanglements across the interfaces, which are essential for improved interfacial adhesion in the final composites. This modification technique could probably be utilized to make fiber-based composites with better mechanical properties. To be able to better compare this physical modification technique with a more traditional covalent grafting-from approach a method to measure attached amounts of grafted PCL onto cellulose model surfaces was developed in paper IV using a quartz crystal microbalance (QCM).

    In paper V, multilayers of poly(allylamine hydrochloride) (PAH) and hyaluronic acid (HA) were assembled using the LbL technique and surface structure, build-up and adhesive behavior of the multilayers were evaluated. AFM force measurements showed that a significant adhesion even at long separation distances between two surfaces treated with PAH/HA multilayers could be achieved due to extensive interdiffusion across the interface during contact, leading to significant disentanglement during separation. Fundamental parameters contributing to improved adhesion for this type of system have been evaluated and this knowledge could be used to improve cellulose-based fiber networks and possibly also other types of cellulose-based materials.

    In paper VI, click chemistry was used to covalently attach dendrons to cellulose surfaces and further modify them with mannose groups to obtain specific interactions with Concanavalin A. The protein interactions were studied at different protein concentrations with a QCM. The multivalent dendronized surface showed a 10-fold increase in sensitivity to the protein compared to a monovalent reference surface demonstrating greatly improved interfacial interactions. This approach could be used to improve interactions at different types of interfaces.

  • 1485.
    Utsel, Simon
    et al.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik. KTH, Skolan för teknikvetenskap (SCI), Centra, VinnExcellens Centrum BiMaC Innovation.
    Malmström, Eva
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik.
    Carlmark, Anna
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik.
    Wågberg, Lars
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik.
    Interactive nano fibrils2009Konferansepaper (Annet vitenskapelig)
  • 1486.
    Utsel, Simon
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Centra, VinnExcellens Centrum BiMaC Innovation. KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknik, Fiberteknologi.
    Montanez, Maria
    Hed, Yvonne
    Ropponen, Jarmo
    Malmström, Eva
    Wågberg, Lars
    Hult, Anders
    Malkoch, Michael
    Dendronized cellulose surfaces as biosensors2012Konferansepaper (Annet vitenskapelig)
  • 1487.
    Uusitaloa, R. -R
    et al.
    Univ Turku, Dept Phys & Astron, Turku, Finland.; Turku Univ, Ctr Mat & Surfaces MatSurf, Turku, Finland.
    Lahtia, A.
    Univ Turku, Dept Phys & Astron, Turku, Finland.;Turku Univ, Ctr Mat & Surfaces MatSurf, Turku, Finland..
    Levämäki, H.
    Univ Turku, Dept Phys & Astron, Turku, Finland.;Turku Univ, Ctr Mat & Surfaces MatSurf, Turku, Finland..
    Punkkinen, M. P. J.
    Univ Turku, Dept Phys & Astron, Turku, Finland.;Turku Univ, Ctr Mat & Surfaces MatSurf, Turku, Finland..
    Vilja, I.
    Univ Turku, Dept Phys & Astron, Turku, Finland.;Turku Univ, Ctr Quantum Phys, Turku, Finland..
    Kokko, K.
    Univ Turku, Dept Phys & Astron, Turku, Finland.;Turku Univ, Ctr Mat & Surfaces MatSurf, Turku, Finland..
    Vitos, Levente
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Materialteori. Royal Inst Technol, Dept Mat Sci & Engn, Appl Mat Phys, Stockholm, Sweden.; Wigner Res Ctr Phys, Inst Solid State Phys & Opt, Budapest, Hungary..
    Order-disorder transition of Pd0.5Ag0.5 alloys2016Inngår i: Philosophical Magazine, ISSN 1478-6435, E-ISSN 1478-6443, Vol. 96, nr 36, s. 3697-3710Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Ab initio total-energy calculations, based on the exact muffin-tin orbitals method, are used to determine the equilibrium chemical configuration of Pd0.5Ag0.5 alloy as a function of disorder and temperature. The transition from a substitutionally disordered face-centred-cubic crystallographic phase to an ordered L1(1) phase is monitored using the coherent potential approximation which allows us to continuously scan the order parameter and thermodynamics of the alloy. We find signs of a first-order phase transition from a substitutionally disordered state to a partially ordered state around 210 K temperature and the completely ordered L1(1) state is predicted around 90 K.

  • 1488.
    Vagin, Mikhail Yu.
    et al.
    Linköpings universitet, Tekniska fakulteten. Linköpings universitet, Institutionen för fysik, kemi och biologi, Kemiska och optiska sensorsystem.
    Jeerapan, Itthipon
    Linköpings universitet, Tekniska fakulteten. Linköpings universitet, Institutionen för fysik, kemi och biologi, Biosensorer och bioelektronik. Hat Yai, Songkla, Thailand.
    Wannapob, Rodtichoti
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biosensorer och bioelektronik. Linköpings universitet, Tekniska fakulteten. Hat Yai, Songkla, Thailand.
    Thavarungkul, Panote
    Hat Yai, Songkla, Thailand.
    Kanatharana, Proespichaya
    Hat Yai, Songkla, Thailand.
    Anwar, Nargis
    Dublin Road, Dundalk, County Louth, Ireland.
    McCormac, Timothy
    Dublin Road, Dundalk, County Louth, Ireland.
    Eriksson, Mats
    Linköpings universitet, Tekniska fakulteten. Linköpings universitet, Institutionen för fysik, kemi och biologi, Kemiska och optiska sensorsystem.
    Turner, Anthony P.F
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Biosensorer och bioelektronik. Linköpings universitet, Tekniska fakulteten.
    Jager, Edwin W.H.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensor- och aktuatorsystem. Linköpings universitet, Tekniska fakulteten.
    Wing Cheung, Mak
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Sensor- och aktuatorsystem. Linköpings universitet, Tekniska fakulteten.
    Water-processable polypyrrole microparticle modules for direct fabrication of hierarchical structured electrochemical interfaces2016Inngår i: Electrochimica Acta, ISSN 0013-4686, E-ISSN 1873-3859, Vol. 190, s. 495-503Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Hierarchically structured materials (HSMs) are becoming increasingly important in catalysis, separation and energy applications due to their advantageous diffusion and flux properties. Here, we introduce a facile modular approach to fabricate HSMs with tailored functional conducting polypyrrole microparticles (PPyMP). The PPyMPs were fabricated with a calcium carbonate (CaCO3) template-assisted polymerization technique in aqueous media at room temperature, thus providing a new green chemistry for producing water-processable functional polymers. The sacrificial CaCO3 template guided the polymerization process to yield homogenous PPyMPs with a narrow size distribution. The porous nature of the CaCO3 further allows the incorporation of various organic and inorganic dopants such as an electrocatalyst and redox mediator for the fabrication of functional PPyMPs. Dawson-type polyoxometalate (POM) and methylene blue (MB) were chosen as the model electrocatalyst and electron mediator dopant, respectively. Hierarchically structured electrochemical interfaces were created simply by self-assembly of the functional PPyMPs. We demonstrate the versatility of this technique by creating two different hierarchical structured electrochemical interfaces: POM-PPyMPs for hydrogen peroxide electrocatalysis and MB-PPyMPs for mediated bioelectrocatalysis. We envision that the presented design concept could be extended to different conducting polymers doped with other functional organic and inorganic dopants to develop advanced electrochemical interfaces and to create high surface area electrodes for energy storage.

  • 1489. Vallhov, Helen
    et al.
    Qin, Jian
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Materialfysik, Funktionella material, FNM.
    Johansson, Sara M.
    Ahlborg, Niklas
    Muhammed, Mamoun A.
    KTH, Skolan för informations- och kommunikationsteknik (ICT), Materialfysik, Funktionella material, FNM.
    Scheynius, Annika
    Gabrielsson, Susanne
    The importance of an endotoxin-free environment during the production of nanoparticles used in medical applications2006Inngår i: Nano letters (Print), ISSN 1530-6984, E-ISSN 1530-6992, Vol. 6, nr 8, s. 1682-1686Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We investigated the effect of spherical gold nanoparticles on immature dendritic cells (DCs). Conventionally produced nanoparticles had a maturating effect on the DCs-a result of lipopolysaccharide (LPS) contamination. By modification of the production process, low-LPS particles were obtained, which had practically no effect on phenotypic maturation or cytokine production of the DCs. Our findings emphasize the importance of high purity in the production of nanoparticles, since possible contaminants may interfere with the assessment of biological/medical effects. They also highlight that nanoparticles can function as carriers of immune modulating contaminants.

  • 1490.
    Valvo, Mario
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
    Doubaji, S.
    Univ Cadi Ayyad, FST Marrakech, LCME, Av A Khattabi,BP 549, Marrakech 40000, Morocco.
    Saadoune, I.
    Univ Cadi Ayyad, FST Marrakech, LCME, Av A Khattabi,BP 549, Marrakech 40000, Morocco;Mohamed VI Polytech Univ, Mat Sci & Nanoengn Dept, Lot 660 Hay Moulay Rachid, Benguerir 43150, Morocco.
    Edström, Kristina
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
    Pseudocapacitive charge storage properties of Na2/3Co2/3Mn2/9Ni1/9O2 in Na-ion batteries2018Inngår i: Electrochimica Acta, ISSN 0013-4686, E-ISSN 1873-3859, Vol. 276, s. 142-152Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The behaviour of Na2/3Co2/3Mn2/9Ni1/9O2 in composite electrodes is studied via Na half-cells utilizing a dedicated cyclic voltammetry approach. The application of increasing sweep rates enabled a detailed analysis of the red-ox peaks of this material. All peak currents due to cathodic/anodic processes demonstrated clear capacitive properties. This finding widens the picture of classical Na+ insertion/ extraction in this complex oxide, as purely diffusive processes of Na+ through its layers do not fully explain the pseudocapacitance displayed by its red-ox peaks, which are typically linked to concomitant oxidation state changes for its transition metal atoms and/or phase transitions. No phase transition was observed during in operando X-Ray diffraction upon charge to 4.2 V vs. Na+/Na, proving good structural stability for P2-NaxCo2/3Mn2/9Ni1/9O2 upon Na+ removal. The origin of such pseudocapacitive properties is likely nested in strong electrostatic interactions among the metal oxide slabs and a tendency to release Na+ from its crystallites, e.g. to form surface by-products upon air exposure. Such a reactivity induces defects (e.g. vacancies) in its lattice and charge compensation mechanisms are required to maintain an overall charge neutrality, thus ultimately influencing the electrochemical properties. Possible limiting factors for the performances of this compound in composite coatings are also discussed.

  • 1491.
    Valvo, Mario
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
    Liivat, Anti
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
    Eriksson, Henrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
    Tai, Cheuk-Wai
    Department of Materials and Environmental Chemistry - Arrhenius Laboratory, Stockholm University.
    Edström, Kristina
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
    Towards more environmentally friendly iron-based Li-ion batteries2017Konferansepaper (Annet vitenskapelig)
  • 1492.
    Valvo, Mario
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
    Philippe, Bertrand
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Molekyl- och kondenserade materiens fysik.
    Lindgren, Fredrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
    Check-Wai, Tai
    Arrhenius Laboratory, Department of Materials and Environmental Chemistry, Stockholm.
    Edström, Kristina
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Strukturkemi.
    Insight into the processes controlling the electrochemical reactions of nanostructured iron oxide electrodes in Li- and Na-half cells2016Inngår i: Electrochimica Acta, ISSN 0013-4686, E-ISSN 1873-3859, Vol. 194, s. 74-83Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The kinetics and the processes governing the electrochemical reactions of various types of iron oxide nanostructures (i.e., nanopowders, nanowires and thin-films) have been studied via cyclic voltammetry in parallel with Li- and Na-half cells containing analogous electrolytes (Li+/Na+, ClO4 in EC:DEC). The particular features arising from each electrode architecture are discussed and compared to shed light on the associated behaviour of the reacting nanostructured active materials. The influence of their characteristic structure, texture and electrical wiring on the overall conversion reaction upon their respective lithiation and sodiation has been analyzed carefully. The limiting factors existing for this reaction upon uptake of Li+ and Na+ ions are highlighted and the related issues in both systems are addressed. The results of this investigation clearly prove that the conversion of iron oxide into metallic Fe and Na2O is severely impeded compared to its analogous process upon lithiation, independently of the type of nanostructure involved in such reaction. The diffusion mechanisms of the different ions (i.e., Li+vs. Na+) through the phases formed upon conversion, as well as the influence of various interfaces on the resulting reaction, appear to pose further constraints on an efficient use of these compounds.

  • 1493.
    Van Regemorter, Tanguy
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för materialkemi.
    The Influence of Dopants on the Growth of Diamond by CVD2009Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Diamond is an important material in many industrial applications (e.g., machining of hard materials, bio-electronics, optics, electronics, etc.) because of its exceptional properties such as hardness, tolerance to aggressive environments, compatibility with human tissues, and high carrier mobility. However, a highly controlled method for growing artificial high-purity diamond on a range of different substrates is needed to exploit these exceptional properties. The Chemical Vapour Deposition (CVD) method is a useful tool for this purpose, but the process still needs to be developed further to achieve better control of growth. In this context, the introduction of dopant species into the gas phase has been shown to strongly influence growth rate and surface morphology. Density Functional Theory (DFT) methods are used to deepen our atomic-level understanding of the effect of dopants on the mechanism for CVD growth on diamond. More specifically, the effect of four dopants (N, P, B and S) has been studied on the important reaction steps in the growth mechanism of diamond. Substitution of N into the diamond lattice has generally been found to disfavour critical reaction steps in the growth of the 100-face in diamond. This negative effect has been related to electron transfer from the N dopant into an empty surface state, e.g., a surface carbon radical. In addition, strong surface stabilization is observed for N substitution in certain sites via a beta-scission reconstruction, with the formation of sp2 carbon. These observations correlate well with observed surface degradation and decrease in growth rate when a high concentration of nitrogen gas is introduced into the CVD growth process. The effect of co-adsorbed P, S and B onto the diamond surface has also been investigated for two reaction steps: CH3 adsorption and H abstraction. While P and B are observed to influence these reaction steps, the effect of S is rather limited.

  • 1494. Van Regemorter, Tanguy
    et al.
    Jacobsson, Jesper
    Edvinsson, Tomas
    Beljonne, D
    Cornil, J
    Electronic Structure of Self-Assembled Monolayers on ZnO Surfaces2011Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    Controlling the electronic properties at the interface between organic and inorganic materials is an issue of high interest since it is known to strongly affect the charge injection and the overall efficiency of opto-electronic devices. Self-assembled monolayers (SAMs) can be used to change the electronic properties of the underlying inorganic material and optimize the charge injection occurring at the interface. In this context, we aim here at a fundamental understanding of the electronic processes taking place when SAMs are deposited on ZnO. In particular, our theoretical investigations focus on the origin of the shift in the conduction band upon addition of SAMs on the ZnO surface. Calculations were performed within the framework of density functional theory (DFT) using periodic boundary conditions. The SAMs investigated here are 4-tertbutylpyridine (SAM1) and benzoic acid (SAM2), this latter with three different terminations. We show how the conduction band varies in the presence of SAMs on both polar and non-polar ZnO surfaces, in comparison to the bare surface. We find a shift in opposite direction for SAM1 and SAM2 for both surface orientations. A charge density analysis has been performed to identify the role of the surface orientation, bond dipole and dipole moment of the individual molecules in the observed effect. These theoretical observations have been confronted to preliminary experimental data for ZnO nano-particles with and without SAMs.

  • 1495.
    Verho, Oscar
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Kärkäs, Markus
    Åkermark, Torbjörn
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK), Avdelningen för materialkemi.
    Johnston, Eric V.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Gustafson, Karl
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Tai, Cheuk-Wai
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK), Avdelningen för oorganisk kemi och strukturkemi.
    Svengren, Henrik
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK), Avdelningen för oorganisk kemi och strukturkemi.
    Bäckvall, Jan-Erling
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Åkermark, Björn
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Well-Defined Palladium Nanoparticles Supported on Amino-Functionalized Siliceous Mesocellular Foam: An Efficient Heterogeneous Catalyst for Chemically-Induced H2O OxidationManuskript (preprint) (Annet vitenskapelig)
  • 1496.
    Vikström, Anna C.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK), Avdelningen för miljökemi.
    Warholm, Margareta
    Paulsson, Birgit
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK), Avdelningen för miljökemi.
    Axmon, Anna
    Wirfalt, Elisabet
    Törnqvist, Margareta
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK), Avdelningen för miljökemi.
    Hemoglobin adducts as a measure of variations in exposure to acrylamide in food and comparison to questionnaire data2012Inngår i: Food and Chemical Toxicology, ISSN 0278-6915, E-ISSN 1873-6351, Vol. 50, nr 7, s. 2531-2539Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Measurement of haemoglobin (Hb) adducts from acrylamide (AA) and its metabolite glycidamide (GA) is a possibility to improve the exposure assessment in epidemiological studies of AA intake from food. This study aims to clarify the reliability of Hb-adduct measurement from individual single samples for exposure assessment of dietary AA intake. The intra-individual variations of AA- and GA-adduct levels measured in blood samples collected over 20 months from 13 non-smokers were up to 2-fold and 4-fold, respectively. The corresponding interindividual variations observed between 68 non-smokers, with large differences in AA intake, were 6-fold and 8-fold, respectively. The intra-individual variation of the GA-to-AA-adduct level ratio was up to 3-fold, compared to 11-fold between individuals (n = 68). From AA-adduct levels the average AA daily intake (n = 68) was calculated and compared to that estimated from dietary history methodology: 0.52 and 0.67 mu g/kg body weight and day, respectively. At an individual level the measures showed low association (Rs = 0.39). Conclusions: Dietary AA is the dominating source to measured AA-adduct levels and corresponding inter- and intra-individual variations in non-smokers. Measurements from single individual samples are useful for calculation of average M intake and its variation in a cohort, and for identification of individuals only from extreme intake groups.

  • 1497.
    Vilela, Carla
    et al.
    Department of Chemistry, CICECO – Aveiro Institute of Materials, University of Aveiro, Aveiro 3810-193, Portugal.
    Engström, Joakim
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Valente, Bruno F. A.
    Department of Chemistry, CICECO – Aveiro Institute of Materials, University of Aveiro, Aveiro 3810-193, Portugal.
    Jawerth, Marcus
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Carlmark, Anna
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Freire, Carmen S. R.
    Department of Chemistry, CICECO – Aveiro Institute of Materials, University of Aveiro, Aveiro 3810-193, Portugal.
    Exploiting poly(ɛ-caprolactone) and cellulose nanofibrils modified with latex nanoparticles for the development of biodegradable nanocomposites2018Inngår i: Polymer Composites, ISSN 0272-8397, E-ISSN 1548-0569Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This study reports the development of nanocomposites based on poly(?-caprolactone) (PCL) and cellulose nanofibrils (CNF) modified with cationic latex nanoparticles. The physical adsorption of these water-based latexes on the surface of CNF was studied as an environment-friendly strategy to enhance the compatibility of CNF with a hydrophobic polymeric matrix. The latexes are composed of amphiphilic block copolymers based on cationic poly(N,N-dimethylaminoethyl methacrylate-co-methacrylic acid) as the hydrophilic block, and either poly(methyl methacrylate) or poly(n-butyl methacrylate) as the hydrophobic block. The simple and practical melt-mixing of PCL- and latex-modified CNF yielded white homogeneous nanocomposites with complete embedment of the nanofibrils in the thermoplastic matrix. All nanocomposites are semicrystalline materials with good mechanical properties (Young's modulus?=?43.6?52.3 MPa) and thermal stability up to 335?340°C. Degradation tests clearly showed that the nanocomposites slowly degrade in the presence of lipase-type enzyme. These PCL/CNF-latex nanocomposite materials show great promise as future environmentally friendly packaging materials. POLYM. COMPOS., 2018. ? 2018 Society of Plastics Engineers

  • 1498.
    Villamayor, Michelle M
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska fakulteten. Uppsala Univ, Sweden.
    Keraudy, Julien
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska fakulteten. Oerlikon Balzers, Liechtenstein.
    Shimizu, Tetsuhide
    Tokyo Metropolitan Univ, Japan.
    Viloan, Rommel Paulo
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska fakulteten.
    Boyd, Robert
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska fakulteten.
    Lundin, Daniel
    Univ Paris Saclay, France.
    Greene, Joseph E
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska fakulteten. Univ Illinois, IL 61801 USA.
    Petrov, Ivan
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Tunnfilmsfysik. Linköpings universitet, Tekniska fakulteten. Univ Illinois, IL 61801 USA.
    Helmersson, Ulf
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Plasma och beläggningsfysik. Linköpings universitet, Tekniska fakulteten.
    Low temperature (T-s/T-m < 0.1) epitaxial growth of HfN/MgO(001) via reactive HiPIMS with metal-ion synchronized substrate bias2018Inngår i: Journal of Vacuum Science & Technology. A. Vacuum, Surfaces, and Films, ISSN 0734-2101, E-ISSN 1520-8559, Vol. 36, nr 6, artikkel-id 061511Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Low-temperature epitaxial growth of refractory transition-metal nitride thin films by means of physical vapor deposition has been a recurring theme in advanced thin-film technology for several years. In the present study, 150-nm-thick epitaxial HfN layers are grown on MgO(001) by reactive high-power impulse magnetron sputtering (HiPIMS) with no external substrate heating. Maximum film-growth temperatures T-s due to plasma heating range from 70 to 150 degrees C, corresponding to T-s/T-m = 0.10-0.12 (in which T-m is the HfN melting point in K). During HiPIMS, gas and sputtered metal-ion fluxes incident at the growing film surface are separated in time due to strong gas rarefaction and the transition to a metal-ion-dominated plasma. In the present experiments, a negative bias of 100 V is applied to the substrate, either continuously during the entire deposition or synchronized with the metal-rich portion of the ion flux. Two different sputtering-gas mixtures, Ar/N-2 and Kr/N-2, are employed in order to probe effects associated with the noble-gas mass and ionization potential. The combination of x-ray diffraction, high-resolution reciprocal-lattice maps, and high-resolution cross-sectional transmission electron microscopy analyses establishes that all HfN films have a cube-on-cube orientational relationship with the substrate, i.e., [001](HfN)parallel to[001](MgO) and (100)(HfN)parallel to(100)(MgO). Layers grown with a continuous substrate bias, in either Ar/N-2 or Kr/N-2, exhibit a relatively high mosaicity and a high concentration of trapped inert gas. In distinct contrast, layers grown in Kr/N-2 with the substrate bias synchronized to the metal-ion-rich portion of HiPIMS pulses have much lower mosaicity, no measurable inert-gas incorporation, and a hardness of 25.7 GPa, in good agreement with the results for epitaxial HfN(001) layers grown at T-s = 650 degrees C (T-s/T-m = 0.26). The room-temperature film resistivity is 70 mu Omega cm, which is 3.2-10 times lower than reported values for polycrystalline-HfN layers grown at T-s = 400 degrees C. (c) 2018 Author(s). All article content, except where otherwise noted, is licensed under a Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).

  • 1499.
    Voisin, Hugo
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Gordeyeva, Korneliya
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Siqueira, Gilberto
    Hausmann, Michael
    Studart, Andre
    Bergström, Lennart
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    3D printing of strong lightweight cellular structures using polysaccharide-based composite foamsManuskript (preprint) (Annet vitenskapelig)
  • 1500.
    Volkov, Anton
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Fysik och elektroteknik. Linköpings universitet, Tekniska fakulteten.
    Ionic and electronic transport in electrochemical and polymer based systems2017Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Electrochemical systems, which rely on coupled phenomena of the chemical change and electricity, have been utilized for development an interface between biological systems and conventional electronics.  The development and detailed understanding of the operation mechanism of such interfaces have a great importance to many fields within life science and conventional electronics. Conducting polymer materials are extensively used as a building block in various applications due to their ability to transduce chemical signal to electrical one and vice versa. The mechanism of the coupling between the mass and charge transfer in electrochemical systems, and particularly in conductive polymer based system, is highly complex and depends on various physical and chemical properties of the materials composing the system of interest.

    The aims of this thesis have been to study electrochemical systems including conductive polymer based systems and provide knowledge for future development of the devices, which can operate with both chemical and electrical signals. Within the thesis, we studied the operation mechanism of ion bipolar junction transistor (IBJT), which have been previously utilized to modulate delivery of charged molecules. We analysed the different operation modes of IBJT and transition between them on the basis of detailed concentration and potential profiles provided by the model.

    We also performed investigation of capacitive charging in conductive PEDOT:PSS polymer electrode. We demonstrated that capacitive charging of PEDOT:PSS electrode at the cyclic voltammetry, can be understood within a modified Nernst-Planck-Poisson formalism for two phase system in terms of the coupled ion-electron diffusion and migration without invoking the assumption of any redox reactions.

    Further, we studied electronic structure and optical properties of a self-doped p-type conducting polymer, which can polymerize itself along the stem of the plants. We performed ab initio calculations for this system in undoped, polaron and bipolaron electronic states. Comparison with experimental data confirmed the formation of undoped or bipolaron states in polymer film depending on applied biases.

    Finally, we performed simulation of the reduction-oxidation reaction at microband array electrodes. We showed that faradaic current density at microband array electrodes increases due to non-linear mass transport on the microscale compared to the corresponding macroscale systems.  The studied microband array electrode was used for developing a laccase-based microband biosensor. The biosensor revealed improved analytical performance, and was utilized for in situ phenol detection.

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