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  • 201.
    Carrick, Christopher
    et al.
    KTH Royal Institute of Technology, Sweden.
    Lindström, Stefan B.
    Linköping University, Sweden.
    Larsson, Per Tomas
    RISE., Innventia. KTH Royal Institute of Technology, Sweden.
    Wågberg, Lars Göran
    KTH Royal Institute of Technology, Sweden.
    Lightweight, highly compressible, noncrystalline cellulose capsules2014Inngår i: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 30, nr 26, s. 7635-6744Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We demonstrate how to prepare extraordinarily deformable, gas-filled, spherical capsules from nonmodified cellulose. These capsules have a low nominal density, ranging from 7.6 to 14.2 kg/m3, and can be deformed elastically to 70% deformation at 50% relative humidity. No compressive strain-at-break could be detected for these dry cellulose capsules, since they did not rupture even when compressed into a disk with pockets of highly compressed air. A quantitative constitutive model for the large deformation compression of these capsules is derived, including their high-frequency mechanical response and their low-frequency force relaxation, where the latter is governed by the gas barrier properties of the dry capsule. Mechanical testing corroborated these models with good accuracy. Force relaxation measurements at a constant compression rendered an estimate for the gas permeability of air through the capsule wall, calculated to 0.4 mL μm/m2 days kPa at 50% relative humidity. These properties taken together open up a large application area for the capsules, and they could most likely be used for applications in compressible, lightweight materials and also constitute excellent model materials for adsorption and adhesion studies.

  • 202.
    Carrick, Christopher
    et al.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi, Fiberteknologi.
    Ruda, Marcus
    Pettersson, Bert
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Larsson, Per Tomas
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi, Fiberteknologi. KTH, Skolan för kemivetenskap (CHE), Centra, Wallenberg Wood Science Center.
    Wågberg, Lars
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi, Fiberteknologi. KTH, Skolan för kemivetenskap (CHE), Centra, Wallenberg Wood Science Center.
    Hollow cellulose capsules from CO2 saturated cellulose solutions - Their preparation and characterization2013Inngår i: RSC Advances, ISSN 2046-2069, Vol. 3, nr 7, s. 2462-2469Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A new material consisting of mm-sized hollow cellulose spheres, for biomedical applications or for the preparation of low weight porous materials has been prepared by a unique solution precipitation (SP) method. The technique is based on three separate steps. In the first step, high molecular mass, non-modified cellulose is dissolved in a suitable solvent. This cellulose solution is then saturated with a suitable gas (CO2 or N2 in the present work) and finally this gas-saturated solution is drop-wise added to a water reservoir. In this step, the cellulose is precipitated and a gas bubble is nucleated in the center of the cellulose sphere. When stored in water, the hollow center is filled with water, indicating that the capsule wall is porous in nature. This was also supported by BET-area measurements as well as by high resolution SEM-images of broken capsule walls. The internal void volume of a capsule was about 5 μl and the wall volume was about 8 μl. It was also established that the properties of the cellulose capsules, i.e. wall and void volume, the specific surface area, the average pore size of the capsule wall, the wall density, and the compressive load capacity could be tuned by the choice of cellulose concentration in the solution before precipitation. The capsule wall volume and void volume were also affected by the choice of gas, the gas pressure and the gas dissolution time during the gas saturation step. The response of the cellulose wall of the prepared capsules to changes in pH and ion concentration in the surrounding solution was also investigated. The swelling-shrinking behavior was further investigated by introducing more charges to the capsule wall, via carboxymethylation of the cellulose. This was achieved by using carboxymethylated cellulose which increased the swelling-shrinking effect. The results show a typical polyelectrolyte gel behavior of the capsule wall and the wet modulus of the cellulose wall was determined to be between 0.09-0.2 MPa depending on the charge of the cellulose in the capsule wall. Furthermore, the freeze dried cellulose spheres had a modulus of 1.9-7.4 MPa, depending on the cellulose concentration during the preparation of the spheres. These cellulose capsules are suitable both for the preparation of porous materials, where these larger spheres are joined together in 3D-shaped materials, and for controlled release where the interior of the capsules is filled with active substances and these substances are released by controlling the pores in the capsule walls.

  • 203.
    Carrick, Christopher
    et al.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi, Fiberteknologi.
    Wågberg, Lars
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi, Fiberteknologi.
    Aidun, Cyrus
    Preparation of cellulose capsule: New renewable material based on regenerated cellulose from the LiCl/DMAc solvent system2012Inngår i: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 243Artikkel i tidsskrift (Annet vitenskapelig)
  • 204.
    Carrick, Christopher
    et al.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Wågberg, Lars
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Larsson, Per A.
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi. KTH, Skolan för teknikvetenskap (SCI), Centra, VinnExcellens Centrum BiMaC Innovation.
    Immunoselective cellulose nanospheres by antibody conjugation2014Inngår i: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 247, s. 727-COLL-Artikkel i tidsskrift (Annet vitenskapelig)
  • 205.
    Cavalcante, Larissa Lopes
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi. Department of Palaeobiology, Swedish Museum of Natural History, SE–104 05 Stockholm, Sweden.
    Barbolini, Natasha
    Department of Ecology, Environment and Plant Sciences and Bolin Centre for Climate Research, Stockholm University, SE-106 91 Stockholm, Sweden; Department of Biological Sciences, University of Bergen and Bjerknes Centre for Climate Research, Bergen, Norway.
    Bacsik, Zoltán
    Department of Materials and Environmental Chemistry, Stockholm University, SE-106 91 Stockholm, Sweden.
    Vajda, Vivi
    Department of Palaeobiology, Swedish Museum of Natural History, SE–104 05 Stockholm, Sweden.
    Analysis of fossil plant cuticles using vibrational spectroscopy: A new preparation protocol2023Inngår i: Review of Palaeobotany and Palynology, ISSN 0034-6667, E-ISSN 1879-0615, Vol. 316, artikkel-id 104944Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Analyses for organic “fingerprints” on fossilized plant cuticles and pollen hold valuable chemotaxonomic and palaeoclimatic information, and are thus becoming more utilized by palaeobotanists. Plant cuticle and pollen composition are generally analyzed after standard treatments with several chemical reagents for mineral and mesophyll removal. However, the potential alterations on the fossil composition caused by the different cleaning reagents used are still poorly understood. We tested the effects of commonly used palaeobotanical processing methods on the spectra of fossilized cuticles from successions of Late Triassic to Early Jurassic age, including the gymnosperms Lepidopteris, Ginkgoites, Podozamites, Ptilozamites and Pterophyllum astartense. Our study shows that standard chemical processing caused chemical alterations that might lead to erroneous interpretation of the infrared (IR) spectra. The difference in pH caused by HCl induces changes in the proportion between the two bands at ∼ 1720 and 1600 cm−1 (carboxylate and C-C stretch of aromatic compounds) indicating that the band at ∼ 1610 cm−1 at least partially corresponds to carboxylate instead of C-C stretch of aromatic compounds. Interestingly, despite being used in high concentration, HF did not cause changes in the chemical composition of the cuticles. The most alarming changes were caused by the use of Schulze's solution, which resulted in the addition of both NO2 and (O)NO2 compounds in the cuticle. Consequently, a new protocol using H2CO3, HF, and H2O2 for preparing fossil plant cuticles aimed for chemical analyses is proposed, which provides an effective substitute to the conventional methods. In particular, a less aggressive and more sustainable alternative to Schulze's solution is shown to be hydrogen peroxide, which causes only minor alteration of the fossil cuticle's chemical composition. Future work should carefully follow protocols, having in mind the impacts of different solutions used to treat leaves and other palaeobotanical material such as palynomorphs with aims to enable the direct comparison of spectra obtained in different studies.

  • 206.
    Cederwall, Ida
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för farmaceutisk biovetenskap.
    Topical formulation of antimicrobials for wound care2022Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [en]

    The increasing spread of antibiotic resistance among bacteria poses a major threat to the public health. There is an urge for the development of innovative formulations of existing and new antibiotics. One area of interest is in wound care, where two interesting antimicrobials are the conventional antibiotic amoxicillin and the antimicrobial peptide AP114. The objective of this work was to systemically evaluate topical gel formulations of these APIs by following a Quality by Design approach. A short excipient compatibility study was performed and the thickening agents poloxamer 407 and HPMC were chosen to be included in the following Design of Experiment (DoE) study of formulation composition and storage climate. The DoE set up was generated by the software MODDE Pro® and a short stability study of four weeks was performed, including analysis of the apparent pH, rheology stability, appearance, BCA assay, UV-Vis and FTIR spectroscopy and Franz cell diffusion. The results showed that AP114 formulations stored at 2-8˚C with poloxamer 407 should be with buffer pH 5-6 and 5-15 wt% organic phase to maximize stability, while HPMC based AP114 gels should be with buffer pH 6-8 and 10-40 wt% organic phase. Poloxamer 407 was not preferrable for amoxicillin formulations. The optimal HPMC based amoxicillin formulations included the storage temperature 25˚C, a buffer pH 7-8 and 40-60 wt% organic phase. HPMC based amoxicillin gels stored at 2-8˚C should be composed with buffer pH 6-8 and 10-40 wt% organic phase. 

    Fulltekst (pdf)
    fulltext
  • 207.
    Cha, Gihoon
    et al.
    Univ Erlangen Nurnberg, Inst Surface Sci & Corros WW4 LKO, Dept Mat Sci, Martensstr 7, D-91058 Erlangen, Germany..
    Hwang, Imgon
    Univ Erlangen Nurnberg, Inst Surface Sci & Corros WW4 LKO, Dept Mat Sci, Martensstr 7, D-91058 Erlangen, Germany..
    Hejazi, Seyedsina
    Univ Erlangen Nurnberg, Inst Surface Sci & Corros WW4 LKO, Dept Mat Sci, Martensstr 7, D-91058 Erlangen, Germany.;Univ Siegen, Chem & Struct Novel Mat, Paul Bonatz Str 9-11, D-57076 Siegen, Germany..
    Dobrota, Ana S.
    Univ Belgrade, Fac Phys Chem, Studentski Trg 12-16, Belgrade 11000, Serbia..
    Pasti, Igor A.
    Univ Belgrade, Fac Phys Chem, Studentski Trg 12-16, Belgrade 11000, Serbia.;KTH Royal Inst Technol, Sch Ind Engn & Management, Dept Mat Sci & Engn, Brinellvagen 23, S-10044 Stockholm, Sweden..
    Osuagwu, Benedict
    Univ Erlangen Nurnberg, Inst Surface Sci & Corros WW4 LKO, Dept Mat Sci, Martensstr 7, D-91058 Erlangen, Germany..
    Kim, Hyesung
    Univ Erlangen Nurnberg, Inst Surface Sci & Corros WW4 LKO, Dept Mat Sci, Martensstr 7, D-91058 Erlangen, Germany..
    Will, Johannes
    Univ Erlangen Nurnberg, Inst Micro & Nanostruct Res & Ctr Nanoanal & Elec, IZNF, Cauerstr 3, D-91058 Erlangen, Germany..
    Yokosawa, Tadahiro
    Univ Erlangen Nurnberg, Inst Micro & Nanostruct Res & Ctr Nanoanal & Elec, IZNF, Cauerstr 3, D-91058 Erlangen, Germany..
    Badura, Zdenek
    Reg Ctr Adv Technol & Mat, Slechtitelu 27, Olomouc 78371, Czech Republic..
    Kment, Stepan
    Reg Ctr Adv Technol & Mat, Slechtitelu 27, Olomouc 78371, Czech Republic..
    Mohajernia, Shiva
    Univ Erlangen Nurnberg, Inst Surface Sci & Corros WW4 LKO, Dept Mat Sci, Martensstr 7, D-91058 Erlangen, Germany.;Univ Siegen, Chem & Struct Novel Mat, Paul Bonatz Str 9-11, D-57076 Siegen, Germany..
    Mazare, Anca
    Univ Erlangen Nurnberg, Inst Surface Sci & Corros WW4 LKO, Dept Mat Sci, Martensstr 7, D-91058 Erlangen, Germany..
    Skorodumova, Natalia V.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Materialteori. KTH Royal Inst Technol, Sch Ind Engn & Management, Dept Mat Sci & Engn, Brinellvagen 23, S-10044 Stockholm, Sweden..
    Spiecker, Erdmann
    Univ Erlangen Nurnberg, Inst Micro & Nanostruct Res & Ctr Nanoanal & Elec, IZNF, Cauerstr 3, D-91058 Erlangen, Germany..
    Schmuki, Patrik
    Univ Erlangen Nurnberg, Inst Surface Sci & Corros WW4 LKO, Dept Mat Sci, Martensstr 7, D-91058 Erlangen, Germany.;Reg Ctr Adv Technol & Mat, Slechtitelu 27, Olomouc 78371, Czech Republic.;King Abdulaziz Univ, Fac Sci, Dept Chem, POB 80203, Jeddah 21569, Saudi Arabia..
    As a single atom Pd outperforms Pt as the most active co-catalyst for photocatalytic H-2 evolution2021Inngår i: iScience, E-ISSN 2589-0042 , Vol. 24, nr 8, artikkel-id 102938Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Here, we evaluate three different noble metal co-catalysts (Pd, Pt, and Au) that are present as single atoms (SAs) on the classic benchmark photocatalyst, TiO2. To trap the single atoms on the surface, we introduced controlled surface vacancies (Ti3+-Ov) on anatase TiO2 nanosheets by a thermal reduction treatment. After anchoring identical loadings of single atoms of Pd, Pt, and Au, we measure the photocatalytic H-2 generation rate and compare it to the classic nanoparticle co-catalysts on the nanosheets. While nanoparticles yield the well-established the hydrogen evolution reaction activity sequence (Pt > Pd > Au), for the single atom form, Pd radically outperforms Pt and Au. Based on density functional theory (DFT), we ascribe this unusual photocatalytic co-catalyst sequence to the nature of the charge localization on the noble metal SAs embedded in the TiO2 surface.

    Fulltekst (pdf)
    FULLTEXT01
  • 208.
    Charlène, Reverdy
    et al.
    CNRS, France; Grenoble Institute of Technology, France.
    Sedighi Moghaddam, Maziar
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Material och ytteknik.
    Sundin, Mikael
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Material och ytteknik.
    Swerin, Agne
    RISE., SP – Sveriges Tekniska Forskningsinstitut, SP Kemi Material och Ytor, Material och ytteknik.
    Julien, Bras
    CNRS, France; Grenoble Institute of Technology, France.
    Superhydrophobic surfaces manufacturing with nanocellulose2016Inngår i: N.I.C.E. 2016 - The 3rd International Conference on Bioinspired and Biobased Chemistry & Materials, 2016Konferansepaper (Fagfellevurdert)
    Abstract [en]

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

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

    Fulltekst (pdf)
    Poster
  • 209.
    Chatterjee, S
    et al.
    Swiss Federal Institute for Materials Science and Technology, Empa.
    Wang, J.W.
    National Cheng Kung University, Taiwan.
    Kuo, W.S.
    Feng Chia University, Taiwan.
    Tai, N.H.
    National Tsing Hua University, Hsinchu, Taiwan.
    Salzmann, C.
    University College London, London, UK.
    Li, W.L.
    Hollertz, Rebecca
    Swiss Fed Labs Mat Sci & Technol Empa, Lab Funct Polymers, Switzerland.
    Nüesch, F.
    Chu, B.T.T.
    Mechanical reinforcement and thermal conductivity in expanded graphene nanoplatelets reinforced epoxy composites2012Inngår i: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 531, s. 6-10Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Influence of reinforcements on mechanical and thermal properties of graphene nanoplatelets/epoxy composites is investigated. Amine functionalized expanded graphene nanoplatelets (EGNPs) were dispersed within epoxy resins using high-pressure processor followed by three roll milling. Functionality on the EGNPs was confirmed with FTIR and micro-Raman spectroscopy. Bending and nano-mechanical testing was performed on the composites. Incorporation of EGNPs improved the flexural modulus and hardness of the composite and increased fracture toughness by up to 60%. Marked improvement was observed in thermal conductivity of the composites reaching 36% at 2 wt.% loading. Functionalized EGNPs exhibited significant improvements indicating favorable interaction at EGNPs/polymer interface.

  • 210.
    Chatzidaki, Maria D.
    Örebro universitet, Institutionen för naturvetenskap och teknik.
    Formulation and characterization of W/O nano-dispersions for bioactive delivery applications2016Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The main objective of this study was the formulation of food-grade water-in-oil (W/O) nano-dispersions based mainly on medium or long-chain triglycerides. Two types of dispersions were formulated and structurally compared, namely emulsions and microemulsions. The systems were used as matrices for encapsulating targeted bioactive molecules with specific characteristics such as antioxidants or peptides.

    The structural characterization of the formulated systems was investigated using techniques such as Electron Paramagnetic Resonance (EPR) spectroscopy, Dynamic Light Scattering (DLS), Cryogenic Transmission Electron Microscopy (Cryo-TEM) and Small Angle Xray Scattering (SAXS). The existence of swollen inverse micelles was revealed for the case of microemulsions whereas larger droplets still at the nano-scale were observed for the case of emulsions. Structural differences in the presence of the bioactive molecules or induced by the alteration of components were also observed.

    In order to study the efficacy of the formulations, the proposed loaded systems were assessed either using EPR spectroscopy or Well Diffusion Assay (WDA) depending on the bioactive molecule. It was found that the encapsulated molecules retained their claimed characteristics when encapsulated to the proposed matrices.

    Finally, some of the formulated dispersions were investigated for their behavior under gastrointestinal (GI) conditions. A two-step digestion model using recombinant Dog Gastric Lipase (rDGL) and Porcine Pancreatic Lipase (PPL) was proposed to simulate lipid hydrolysis in humans. The studies revealed significant decrease of the rDGL specific activity in the presence of the microemulsion while in the presence of lower percent of surfactants (case of emulsion) no alterations were observed.

    Fulltekst (pdf)
    Introductory chapter
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    Cover
  • 211.
    Chatzidaki, Maria D.
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik. Inst Biol Med Chem & Biotechnol, Natl Hellen Res Fdn, Athens, Greece.
    Arik, Nehir
    Inst Biol Med Chem & Biotechnol, Natl Hellen Res Fdn, Athens, Greece.
    Monteil, Julien
    Institut de Chimie & Biologie des Membranes & des Nano-objets (CBMN), Univ Bordeaux, Bordeaux, France.
    Papadimitriou, Vassiliki
    Inst Biol Med Chem & Biotechnol, Natl Hellen Res Fdn, Athens, Greece.
    Leal-Calderon, Fernando
    Institut de Chimie & Biologie des Membranes & des Nano-objets (CBMN), Univ Bordeaux, Bordeaux, France.
    Xenakis, Aristotelis
    Inst Biol Med Chem & Biotechnol, Natl Hellen Res Fdn, Athens, Greece.; Sch Sci & Technol, MTM Res Ctr, Univ Örebro, Örebro, Sweden.
    Microemulsion versus emulsion as effective carrier of hydroxytyrosol2016Inngår i: Colloids and Surfaces B: Biointerfaces, ISSN 0927-7765, E-ISSN 1873-4367, Vol. 137, nr 1, s. 146-151Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Two edible Water-in-Oil (W/O) dispersions, an emulsion that remains kinetically stable and a microemulsion which is spontaneously formed, transparent and thermodynamically stable, were developed for potential use as functional foods, due to their ability to be considered as matrices to encapsulate biologically active hydrophilic molecules. Both systems contained Medium Chain Triglycerides (MCT) as the continuous phase and were used as carriers of Hydroxytyrosol (HT), a hydrophilic antioxidant of olive oil. A low energy input fabrication process of the emulsion was implemented. The obtained emulsion contained 1.3% (w/w) of surfactants and 5% (w/w) aqueous phase. The spontaneously formed microemulsion contained 4.9% (w/w) of surfactants and 2% (w/w) aqueous phase. A comparative study in terms of structural characterization of the systems in the absence and presence of HT was carried out. Particle size distribution obtained by Dynamic Light Scattering (DLS) technique and interfacial properties of the surfactants' layer, examined by Electron Paramagnetic Resonance (EPR) spectroscopy indicated the involvement of HT in the surfactant membrane. Finally, the proposed systems were studied for the scavenging activity of the encapsulated antioxidant toward galvinoxyl stable free radical showing a high scavenging activity of HT in both systems.

  • 212.
    Chatzidaki, Maria D.
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik. National Hellenic Research Foundation Institute of Biology Medicinal Chemistry and Biotechnology.
    Eduardo, Mateos-Diaz
    CNRS, UMR7282 Enzymologie Interfaciale et Physiologie de la Lipolyse.
    Leal-Calderon, Fernando
    Polytechnic Institute of Bourdeaux, CBMN.
    Xenakis, Aristotelis
    National Hellenic Research Foundation Institute of Biology Medicinal Chemistry and Biotechnology.
    Carrière, Frédéric
    CNRS, UMR7282 Enzymology at Interfaces and Physiology of Lipolysis.
    Water-in-Oil microemulsions versus emulsions as carriers of hydroxytyrosol: an in vitro gastrointestinal lipolysis study using the pHstat techniqueManuskript (preprint) (Annet vitenskapelig)
  • 213.
    Chatzidaki, Maria D.
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik. Inst Biol Med Chem & Biotechnol, Natl Hellen Res Fdn, Athens, Greece.
    Mitsou, Evgenia
    Inst Biol Med Chem & Biotechnol, Natl Hellen Res Fdn, Athens, Greece..
    Yaghmur, Anan
    Fac Hlth & Med Sci, Dept Pharm, Univ Copenhagen, Copenhagen, Denmark..
    Xenakis, Aristotelis
    Inst Biol Med Chem & Biotechnol, Natl Hellen Res Fdn, Athens, Greece; Sch Sci & Technol, MTM Res Ctr, Univ Örebro, Örebro, Sweden.
    Papadimitriou, Vassiliki
    Inst Biol Med Chem & Biotechnol, Natl Hellen Res Fdn, Athens, Greece..
    Formulation and characterization of food-grade microemulsions as carriers of natural phenolic antioxidants2015Inngår i: Colloids and Surfaces A: Physicochemical and Engineering Aspects, ISSN 0927-7757, E-ISSN 1873-4359, Vol. 483, s. 130-136Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Food-grade W/O microemulsions based on lecithin, caprylic/capric triglycerides, isopropyl myristate, alcohols and water were formulated and structurally characterized to be used as potential carriers of natural food antioxidants. Different well-known food antioxidants including gallic acid, p-hydroxybenzoic acid, protocatechuic acid and tyrosol were successfully encapsulated in the aqueous cores of the microemulsions. A pseudo-ternary phase diagram was constructed to determine the extent of the monophasic area that corresponds to an inverted type microemulsion. Apparent hydrodynamic diameter measurements of empty and loaded microemulsions were performed using dynamic light scattering (DLS) and swollen micelles with diameters smaller than 10 nm were detected. Interfacial properties of the microemulsions were studied by electron paramagnetic resonance (EPR) spectroscopy employing the nitroxide spin probe 5-doxylstearic acid (5-DSA). A small increase in spin probe mobility upon addition of the antioxidants was observed; whereas the rigidity of the surfactants was not affected. Cryogenic transmission electron microscopy (Cryo-TEM) indicated the existence of entangled thread-like reversed micelles. Finally, the investigated phenolics were assessed and compared for their radical scavenging activity using an EPR approach based on free radicals. The encapsulated gallic acid showed the highest antioxidant activity (0.93 mM trolox equivalents) as compared to other antioxidants assessed within the frame of this study.

  • 214.
    Chatzidaki, Maria D.
    et al.
    Örebro universitet, Institutionen för naturvetenskap och teknik. Institute of Biology Medicinal Chemistry & Biotechnology, NHRF, Athens, Greece.
    Papadimitriou, Konstantinos
    Agricultural University of Athens.
    Alexandraki, Voula
    Agricultural University of Athens.
    Tsirvouli, Eirini
    Institute of Biology Medicinal Chemistry & Biotechnology, NHRF, Athens, Greece.
    Chakim, Zena
    Institute of Biology Medicinal Chemistry & Biotechnology, NHRF, Athens, Greece.
    Ghazal, Aghiad
    University of Copenhagen, Denmark.
    Mortensen, Kell
    University of Copenhagen, Denmark.
    Yaghmur, Anan
    University of Copenhagen, Denmark.
    Salentinig, Stefan
    Swiss Federal Laboratories for Materials Science and Technology, St. Gallen, Switzerland.
    Papadimitriou, Vassiliki
    Institute of Biology Medicinal Chemistry & Biotechnology, NHRF, Athens, Greece.
    Tsakalidou, Effie
    Agricultural University of Athens.
    Xenakis, Aristotelis
    Institute of Biology Medicinal Chemistry & Biotechnology, NHRF, Athens, Greece; Örebro University, Sweden .
    Microemulsions as potential carriers of nisin: effect of composition on the structure and efficacyManuskript (preprint) (Annet vitenskapelig)
  • 215.
    Chelcea, Ioana C.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Computational methods for assessing chemical risk: focusing on toxicokinetic modelling in zebrafish (danio rerio)2023Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    New chemicals are constantly produced and large data gaps exist on hazards of currently used industrial chemicals, stressing the need for rapid, ethically sound and cost-efficient hazard assessment methods. Traditional methods for effect assessment based on animal testing, do not meet these requirements and thus the toxicology field has been moving towards the development of new approach methodologies which include in vitro approaches but also computational methods. The current work has mainly focused on computational tools but also employed in vitro and in vivo methodologies for the development and validation of the in silico approaches.

    We firstly explored chemical variation of emerging chemicals as a basis for selecting sub-groups of per- and polyfluoroalkyl substances (PFASs) and bisphenols for Papers I and II. These compounds can be used for future testing and as case study compounds for in silico tools development. The PFASs selection showed compounds with large differences in structure and highlighted the lack of knowledge for large parts of the PFASs chemical domain. This likely is the main driver of the low predictive accuracy of some current fate models and the need for expanding their applicability domains. 

    In Paper II we investigated the toxicokinetics of selected bisphenols in a commonly studied model organism, the zebrafish (Danio rerio), and developed a physiologically-based toxicokinetic model. Novel data for fish biotransformation was derived and showed lower rates than those measured in humans, providing valuable insight for both model parameterization and for chemical safety assessment using fish. The model also demonstrated the ability to predict and rank hazard of these bisphenols in terms of organ-specific bioaccumulation making it a useful tool for chemical screening and prioritization efforts. The results indicate that bisphenols AP, C and Z as well as tetrabromo bisphenol A may have larger potential for bioaccumulation than the widely used bisphenol A (BPA), indicating that these compounds do not constitute safer industrial substitutions.  

    Lastly, we present in Paper III the development of a toxicokinetic model for the zebrafish embryo life-stage. Since the zebrafish embryo test is widely applied in toxicology research, the developed model provides a tool to better understand how varying testing conditions may affect dose at target thus providing a means to compare internal effect concentrations. Additionally, we applied the model in combination with data on estrogenic activity in order to rank the relative hazard of investigated bisphenols, which showed that bisphenols AF, C, B and Z may be more hazardous than BPA.

    Overall the developed computational tools showed good predictive performance and improvements in parameterization, thus providing tools for understanding dose at target and toxicokinetic variation of emerging substances. Furthermore, the thesis presents novel data and findings for per- and polyfluoroalkyl substances and bisphenols, which are environmental pollutants of emerging concern of relevance for future hazard assessments and substitution processes.

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  • 216. Chen, Bin
    et al.
    Li, Xin
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi.
    Wu, Wenjun
    Zha, Quanzheng
    Xie, Yongshu
    A novel trigeminal zinc porphyrin and corresponding porphyrin monomers for dye-sensitized solar cells2014Inngår i: RSC Advances, E-ISSN 2046-2069, Vol. 4, nr 21, s. 10439-10449Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A novel trigeminal zinc porphyrin sensitizer (T) and two zinc porphyrin monomers (M1 and M2) were successfully designed and synthesized. The spectral, electrochemical, and photovoltaic properties of the porphyrin dyes were investigated. Compared with M1, the molecule of M2 has an additional aliphatic n-hexyloxyl chain at the meso-position of the porphyrin framework, and such a structure is favorable for the formation of a compact hydrophobic layer at the TiO2 surface and the retardation of the diffusion of I-3(-) ions into the nanoporous TiO2 electrode, resulting in more effective suppression of the charge recombination process and a higher V-oc. Meanwhile, M2 has larger IPCE values than those of M1, leading to the higher J(sc) value. Thus, the DSSC devices based on M2 demonstrated a relatively high power conversion efficiency of 5.77%, with the J(sc), V-oc and ff values of 13.93 mA cm(-2), 732 mV, and 0.566, respectively. Even though dye T has the highest molar absorption coefficients and multiple binding moieties, the corresponding power conversion efficiency is 2.30%, which is lower than those for M1 and M2. These observations may be ascribed to the low efficiency of the electron injection process caused by the isolation of the LUMOs from the anchoring carboxyl groups in addition to the lowest adsorption amount.

  • 217. Chen, Cheng
    et al.
    Yang, Xichuan
    Cheng, Ming
    Zhang, Fuguo
    Zhao, Jianghua
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Highly efficient organic dyes containing a benzopyran ring as a pi-bridge for DSSCs2013Inngår i: RSC Advances, E-ISSN 2046-2069, Vol. 3, nr 31, s. 12688-12693Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A series of novel organic dyes containing a benzopyran ring as a p-bridge have been designed and applied in dye-sensitized solar cells (DSSCs). This series of dyes show the excellent DSSCs' performance, due to their efficient light-to-photocurrent conversion in the region from 380 nm to 600 nm, with the highest IPCE values exceeding 90%. Through modification of the donor units, an efficiency as high as 7.5% has been achieved under standard light illumination (AM 1.5G, 100 mW cm(-2)) by the dye CC103.

  • 218. Chen, Guanying
    et al.
    Ohulchanskyy, Tymish Y.
    Kachynski, Aliaksandr
    Ågren, Hans
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi.
    Prasad, Paras N.
    Intense Visible and Near-Infrared Upconversion Photoluminescence in Colloidal LiYF4:Er3+ Nanocrystals under Excitation at 1490 nm2011Inngår i: ACS NANO, ISSN 1936-0851, Vol. 5, nr 6, s. 4981-4986Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We report intense upconversion photoluminescence (PL) In colloidal LiYF4:Er(3+)nanocrystals under excitation with telecom-wavelength at 1490 nm. The intensities of two- and three-photon anti-Stokes upconversion PL bands are higher than or comparable to that of the Stokes emission under excitation with low power density in the range 5-120 W/cm(2). The quantum yield of the uptonversion PL was measured to be as high as similar to 1.2 +/- 0.1%, which is almost 4 times higher than the highest upconversion PL quantum yield reported to date for lanthanide-doped nanocrystals In 100 nm sized hexagonal NaYF4:Yb(3+)20%, Er(3+)2% using excitation at similar to 980 nm. A power dependence study revealed that the intensities of all PL bands have linear dependence on the excitation power density, which was explained by saturation effects in the intermediate energy states.

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

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

  • 220.
    Chen, Lu
    et al.
    Ecole Polytech Fed Lausanne EPFL, Inst Chem Sci & Engn, Lab Organometall & Med Chem, CH-1015 Lausanne, Switzerland..
    Pan, Linfeng
    Ecole Polytech Fed Lausanne EPFL, Inst Chem Sci & Engn, Lab Organometall & Med Chem, CH-1015 Lausanne, Switzerland.;Ecole Polytech Fed Lausanne, Inst Chem Sci & Engn, Lab Photomol Sci, CH-1015 Lausanne, Switzerland..
    van Muyden, Antoine P.
    Ecole Polytech Fed Lausanne EPFL, Inst Chem Sci & Engn, Lab Organometall & Med Chem, CH-1015 Lausanne, Switzerland..
    Bai, Lichen
    Ecole Polytech Fed Lausanne, Inst Chem Sci & Engn, Lab Inorgan Synth & Catalysis, CH-1015 Lausanne, Switzerland..
    Li, Jun
    Ecole Polytech Fed Lausanne, Inst Chem Sci & Engn, Lab Photon & Interfaces, CH-1015 Lausanne, Switzerland..
    Tong, Yun
    Ecole Polytech Fed Lausanne EPFL, Inst Chem Sci & Engn, Lab Organometall & Med Chem, CH-1015 Lausanne, Switzerland.;Zhejiang Sci Tech Univ, Sch Sci, Dept Chem, 928 Second Ave, Hangzhou 310018, Peoples R China..
    Fei, Zhaofu
    Ecole Polytech Fed Lausanne EPFL, Inst Chem Sci & Engn, Lab Organometall & Med Chem, CH-1015 Lausanne, Switzerland..
    Hagfeldt, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för kemi - Ångström, Fysikalisk kemi. Ecole Polytech Fed Lausanne, Inst Chem Sci & Engn, Lab Photomol Sci, CH-1015 Lausanne, Switzerland..
    Laurenczy, Gabor
    Ecole Polytech Fed Lausanne EPFL, Inst Chem Sci & Engn, Lab Organometall & Med Chem, CH-1015 Lausanne, Switzerland..
    Dyson, Paul J.
    Ecole Polytech Fed Lausanne EPFL, Inst Chem Sci & Engn, Lab Organometall & Med Chem, CH-1015 Lausanne, Switzerland..
    Anchoring single platinum atoms onto nickel nanoparticles affords highly selective catalysts for lignin conversion2021Inngår i: Cell Reports Physical Science, E-ISSN 2666-3864, Vol. 2, nr 9, artikkel-id 100567Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Due to the highly complex polyphenolic structure of lignin, depolymerization without a prior chemical treatment is challenging, and new catalysts are required. Atomically dispersed catalysts are able to maximize the atomic efficiency of noble metals, simultaneously providing an alternative strategy to tune the activity and selectivity by alloying with other abundant metal supports. Here, we report a highly active and selective catalyst comprising monodispersed (single) Pt atoms on Ni nanoparticles supported on carbon (denoted as Pt1Ni/C, where Pt-1 represents single Pt atoms), designed for the reductive depolymerization of lignin. Selectivity toward 4-n-propylsyringol and 4-n-propylguaiacol exceeds 90%. The activity and selectivity of the Pt1Ni/C catalyst in the reductive depolymerization of lignin may be attributed to synergistic effects between the Ni nanoparticles and the single Pt atoms.

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  • 221. Chen, M.
    et al.
    Xue, S.
    Liu, L.
    Li, Z.
    Wang, H.
    Tan, C.
    Yang, J.
    Hu, X.
    Jiang, X. -F
    Cheng, Y.
    Xing, X.
    He, Sailing
    KTH, Skolan för elektroteknik och datavetenskap (EECS), Elektroteknik, Elektroteknisk teori och konstruktion.
    A highly stable optical humidity sensors based on nano-composite film2019Inngår i: Sensors and actuators. B, Chemical, ISSN 0925-4005, E-ISSN 1873-3077, Vol. 287, s. 329-337Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We report a highly stable humidity sensor based on nanocomposite film obtained by depositing Au nanoparticles on the surface of 3-mercaptopropionic acid (MPA) capped CdTe quantum dots (QDs) and then modifying NaOH (CdTe@Au/NaOH). The CdTe@Au/NaOH film will form compound salts that can be dissolved or crystallized with humidity changes, resulting in a significant absorption variation of green light, which is very benefit for water vapor detection. In this study, we systematically investigated the influence on the performance of humidity sensing by varying the thickness of Au layer as well as the concentration of NaOH. Our results show that the quickest response-recovery time (˜less than 30 s) was found in the sensing film with the Au layer thickness of 20 nm and NaOH concentration of 1M, which can be ascribed to the combined effects of the better morphology and the yield of compound salts. The repeatable response and recovery measurements demonstrate that the designed sensors exhibit an ultralow humidity detection level with fast response-recovery time, high stability and reproducibility at room temperature. The simplicity, low fabrication cost, and wide working range of the humidity sensor will pave the way for its application in environments and gas detection.

  • 222.
    Chen, Xuehan
    et al.
    Nanjing Univ Sci & Technol, Peoples R China.
    Huang, Jing
    Nanjing Univ Sci & Technol, Peoples R China.
    Gao, Feng
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Elektroniska och fotoniska material. Linköpings universitet, Tekniska fakulteten.
    Xu, Bo
    Nanjing Univ Sci & Technol, Peoples R China.
    Perspective Phosphine oxide additives for perovskite diodes and solar cells2023Inngår i: Chem, ISSN 2451-9308, E-ISSN 2451-9294, Vol. 9, nr 3, s. 562-575Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    Lead halide perovskites have been considered promising semicon-ducting materials for next-generation optoelectronic devices due to their solution processability and excellent optoelectronic proper-ties. Device performance of perovskite light-emitting diodes (PeLEDs) and perovskite solar cells (PSCs) has been rapidly devel-oped during the past decade. Very recently, organic molecules containing phosphine oxide groups have emerged as promising ad-ditives and passivators to improve the device performance and sta-bility of both PeLEDs and PSCs. In this perspective, we summarize recent progress in the development of new phosphine-oxide-based additives for PeLEDs and PSCs. The passivation mechanism, molecule design principle, and structure-property relationship of phosphine oxide molecules for PeLEDs and PSCs are systematically discussed and analyzed. Finally, we provide an outlook on the mo-lecular design of novel phosphine oxide compounds for efficient and stable PeLEDs and PSCs in the future.

  • 223.
    Chen, Yingying
    et al.
    East China Univ Sci & Technol, Peoples R China; East China Univ Sci & Technol, Peoples R China.
    Tang, Yunyu
    Chinese Acad Fishery Sci, Peoples R China.
    Zou, Jiazhi
    East China Univ Sci & Technol, Peoples R China; East China Univ Sci & Technol, Peoples R China.
    Zeng, Kaiwen
    East China Univ Sci & Technol, Peoples R China; East China Univ Sci & Technol, Peoples R China.
    Baryshnikov, Glib
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Laboratoriet för organisk elektronik. Linköpings universitet, Tekniska fakulteten.
    Li, Chengjie
    East China Univ Sci & Technol, Peoples R China; East China Univ Sci & Technol, Peoples R China.
    Xie, Yongshu
    East China Univ Sci & Technol, Peoples R China; East China Univ Sci & Technol, Peoples R China.
    Fluorenyl Indoline as an Efficient Electron Donor for Concerted Companion Dyes: Enhanced Light-Harvesting and Photocurrent2021Inngår i: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 13, nr 42, s. 49828-49839Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Concerted companion dyes (CC dyes) like XW61 have been demonstrated to be an effective platform for developing efficient DSSCs. However, the moderated phenothiazine-based electron donor in XW61 results in unsatisfactory J(sc). To address this problem, a stronger fluorenyl indoline-based electron donor has been used to construct porphyrin dye XW68 and organic dyes Y1-Y2. The stronger electron-donating character of the fluorenyl indoline unit leads to an enhanced J(sc) value (20.48 mA.cm(-2)) for the individual dye XW68. On this basis, CC dyes XW69-XW70-C8 have been designed and synthesized by combining the frameworks of Y1 and Y2 with XW68. The complementary absorption characters of the porphyrin and the organic dye moieties lead to panchromatic absorption with a strong light-harvesting capability from 350 to 700 nm and the onset wavelength extended to ca. 840 nm in the IPCE curves. As a result, excellent J(sc) values have been achieved (>22 mA.cm(-2)). In addition to the advantages of high J(sc), bulky octyl groups have been introduced into the donor of XW70-C8 to reduce dye aggregation and suppress charge recombination. Finally, a highest PCE of 11.1% with a satisfactory J(sc) (22.25 mA.cm(-2)) and an enhanced V-oc (750 mV) has been achieved upon coadsorption of XW70-C8 with CDCA. In addition, the CC dye XW70-C8-based solar cells exhibit excellent long-term photostability. These results provide an effective method for rationally improving the photovoltaic behavior, especially the J(sc) of CC dyes, by introducing strong electron donor moieties with suitable substituents.

  • 224. Chenery, S.
    et al.
    Williams, C. T.
    Elliott, T. A.
    Forey, P. L.
    Werdelin, Lars
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    Determination of rare earth elements in biological and mineral apatite by EPMA and LAMP-ICP-MS1996Inngår i: Microchimica Acta, ISSN 0026-3672, E-ISSN 1436-5073, Vol. 13, nr suppl., s. 259-269Artikkel i tidsskrift (Fagfellevurdert)
  • 225.
    Cheng, Jie
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Yt- och korrosionsvetenskap. Tsinghua University, China.
    Pan, Jinshan
    KTH, Skolan för kemivetenskap (CHE), Kemi, Yt- och korrosionsvetenskap.
    Lu, X.
    Micro-galvanic corrosion of cu-ru couple in potassium periodate (KIO4) solution2015Inngår i: European Corrosion Congress, EUROCORR 2015, Austrian Society for Metallurgy and Materials (ASMET) , 2015, Vol. 3, s. 1829-1829Konferansepaper (Fagfellevurdert)
  • 226. Cheng, Ming
    et al.
    Yang, Xichuan
    Chen, Cheng
    Zhao, Jianghua
    Tan, Qin
    Sun, Licheng
    KTH, Skolan för kemivetenskap (CHE), Kemi, Organisk kemi. KTH, Skolan för kemivetenskap (CHE), Centra, Molekylär elektronik, CMD.
    Effect of the acceptor on the performance of dye-sensitized solar cells2013Inngår i: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 15, nr 40, s. 17452-17459Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Three new phenothiazine dyes were designed and synthesized, utilizing different acceptor groups. Upon application to TiO2-based solar cells, the effects of different acceptors on the photophysical and electrochemical properties of the dyes and the solar cell performance are detailed. The introduction of a pyridinium unit or 5-carboxy-1-hexyl-2,3,3-trimethyl-indolium unit into the molecular frame as the acceptor instead of cyano acrylic acid can effectively cause a red shift in the absorption spectra. Applied to DSSCs, the devices sensitized by CM502 with the pyridinium unit as the acceptor show the highest efficiency of 7.3%. The devices fabricated with dye CM501 with cyano acrylic acid as the acceptor exhibited the highest V-oc while for the devices sensitized by the dye CM503 with 5-carboxy-1-hexyl2,3,3- trimethyl-3H-indolium unit as the acceptor, the Voc value was the lowest, at 494 mV. The addition of TBP in the electrolyte can improve the performance of DSSCs fabricated using CM501 and CM502, with the Voc value greatly improved but the J(sc) value slightly decreased. However, with the addition of TBP in the electrolyte, the efficiency of the cells sensitized by CM503 dropped significantly (from 4.9% to 1.0% when 0.1 M TBP was added).

  • 227. Chico, B.
    et al.
    Fuente, D. D. L.
    Jiménez, J. A.
    Chang, Tingru
    KTH, Skolan för kemivetenskap (CHE), Kemi, Yt- och korrosionsvetenskap.
    Odnevall Wallinder, Inger
    KTH, Skolan för kemivetenskap (CHE), Kemi, Yt- och korrosionsvetenskap.
    Leygraf, Christopher
    KTH, Skolan för kemivetenskap (CHE), Kemi, Yt- och korrosionsvetenskap.
    Morcillo, M.
    Analysis of historic copper patinas 2: Characterization of 400 year old patina from Royal Summer Palace in Prague2017Inngår i: EUROCORR 2017 - The Annual Congress of the European Federation of Corrosion, 20th International Corrosion Congress and Process Safety Congress 2017, Asociace koroznich inzenyru z.s.- AKI - Czech Association of Corrosion Engineers , 2017Konferansepaper (Fagfellevurdert)
    Abstract [en]

    This paper presents an in-depth characterisation study of the patina formed on a copper tile taken from the roof of Queen Anne's Summer Palace in Prague after close to 400 years of exposure to the action of the atmosphere. A wide variety of techniques have been performed, including metallographic and chemical analysis (electrogravimetry, AAS, XRF) of the copper matrix, and spectroscopic and microscopic investigations (GIXRD, TEM/EDS and SEM/EDS) to determine the composition and structure of the patina. The major conclusions of the study are: (a) the base copper contains abundant inclusions mainly of rosiaite (PbSb2O6); (b) the patina is formed by an inner sublayer of cuprite (Cu2O) and an outer sublayer of brochantite [Cu4SO4(OH)6] and antlerite [Cu3SO4(OH)4] and traces of azurite [Cu3(CO3)2(OH)2]; and (c) the brochantite/antlerite crystals are randomly doped with Fe and C.

  • 228.
    Chinnasamy, Thiruppathiraja
    et al.
    KTH, Skolan för bioteknologi (BIO), Proteomik och nanobioteknologi. KTH, Centra, Science for Life Laboratory, SciLifeLab.
    Segerink, Loes I.
    Nystrand, Mats
    Gantelius, Jesper
    KTH, Skolan för bioteknologi (BIO), Proteomik och nanobioteknologi. KTH, Centra, Science for Life Laboratory, SciLifeLab.
    Andersson Svahn, Helene
    KTH, Skolan för bioteknologi (BIO), Proteomik och nanobioteknologi. KTH, Centra, Science for Life Laboratory, SciLifeLab.
    Point-of-Care Vertical Flow Allergen Microarray Assay: Proof of Concept2014Inngår i: Clinical Chemistry, ISSN 0009-9147, E-ISSN 1530-8561, Vol. 60, nr 9, s. 1209-1216Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    BACKGROUND: Sophisticated equipment, lengthy protocols, and skilled operators are required to perform protein microarray-based affinity assays. Consequently, novel tools are needed to bring biomarkers and biomarker panels into clinical use in different settings. Here, we describe a novel paper-based vertical flow microarray (VFM) system with a multiplexing capacity of at least 1480 microspot binding sites, colorimetric readout, high sensitivity, and assay time of < 10 min before imaging and data analysis. METHOD: Affinity binders were deposited on nitrocellulose membranes by conventional microarray printing. Buffers and reagents were applied vertically by use of a flow controlled syringe pump. As a clinical model system, we analyzed 31 precharacterized human serum samples using the array system with 10 allergen components to detect specific IgE reactivities. We detected bound analytes using gold nanoparticle conjugates with assay time of <= 10 min. Microarray images were captured by a consumer-grade flatbed scanner. RESULTS: A sensitivity of 1 ng/mL was demonstrated with the VFM assay with colorimetric readout. The reproducibility (CV) of the system was < 14%. The observed concordance with a clinical assay, Immuno-CAP, was R-2 = 0.89 (n = 31). CONCLUSIONS: In this proof-of-concept study, we demonstrated that the VFM assay, which combines features from protein microarrays and paper-based colorimetric systems, could offer an interesting alternative for future highly multiplexed affinity point-of-care testing.

  • 229. Choong, Ferdinand X.
    et al.
    Back, Marcus
    Steiner, Svava E.
    Melican, Keira
    Nilsson, K. Peter R.
    Edlund, Ulrica
    KTH, Skolan för kemivetenskap (CHE), Fiber- och polymerteknologi.
    Richter-Dahlfors, Agneta
    Nondestructive, real-time determination and visualization of cellulose, hemicellulose and lignin by luminescent oligothiophenes2016Inngår i: Scientific Reports, E-ISSN 2045-2322, Vol. 6, artikkel-id 35578Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Enabling technologies for efficient use of the bio-based feedstock are crucial to the replacement of oil-based products. We investigated the feasibility of luminescent conjugated oligothiophenes (LCOs) for non-destructive, rapid detection and quality assessment of lignocellulosic components in complex biomass matrices. A cationic pentameric oligothiophene denoted p-HTEA (pentamer hydrogen thiophene ethyl amine) showed unique binding affinities to cellulose, lignin, hemicelluloses, and cellulose nanofibrils in crystal, liquid and paper form. We exploited this finding using spectrofluorometric methods and fluorescence confocal laser scanning microscopy, for sensitive, simultaneous determination of the structural and compositional complexities of native lignocellulosic biomass. With exceptional photostability, p-HTEA is also demonstrated as a dynamic sensor for real-time monitoring of enzymatic cellulose degradation in cellulolysis. These results demonstrate the use of p-HTEA as a non-destructive tool for the determination of cellulose, hemicellulose and lignin in complex biomass matrices, thereby aiding in the optimization of biomass-converting technologies.

  • 230.
    Choong, Ferdinand X.
    et al.
    Karolinska Inst, Sweden.
    Lantz, Linda
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Kemi. Linköpings universitet, Tekniska fakulteten.
    Shirani, Hamid
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Kemi. Linköpings universitet, Tekniska fakulteten.
    Schulz, Anette
    Karolinska Inst, Sweden.
    Nilsson, Peter
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Kemi. Linköpings universitet, Tekniska fakulteten.
    Edlund, Ulrica
    KTH Royal Inst Technol, Sweden.
    Richter-Dahlfors, Agneta
    Karolinska Inst, Sweden.
    Stereochemical identification of glucans by a donor-acceptor-donor conjugated pentamer enables multi-carbohydrate anatomical mapping in plant tissues2019Inngår i: Cellulose, ISSN 0969-0239, E-ISSN 1572-882X, Vol. 26, nr 7, s. 4253-4264Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Optotracing is a novel method for analytical imaging of carbohydrates in plant and microbial tissues. This optical method applies structure-responsive oligothiophenes as molecular fluorophores emitting unique optical signatures when bound to polysaccharides. Herein, we apply Carbotrace680, a short length anionic oligothiophene with a central heterocyclic benzodithiazole (BTD) motif, to probe for different glucans. The donor-acceptor-donor type electronic structure of Carbotrace680 provides improved spectral properties compared to oligothiophenes due to the possibility of intramolecular charge-transfer transition to the BTD motif. This enables differentiation of glucans based on the glycosidic linkage stereochemistry. Thus -configured starch is readily differentiated from -configured cellulose. The versatility of optotracing is demonstrated by dynamic monitoring of thermo-induced starch remodelling, shown in parallel by spectrophotometry and microscopy of starch granules. Imaging of Carbotrace680 bound to multiple glucans in plant tissues provided direct identification of their physical locations, revealing the spatial relationship between structural (cellulose) and storage (starch) glucans at sub-cellular scale. Our work forms the basis for the development of superior optotracers for sensitive detection of polysaccharides. Our non-destructive method for anatomical mapping of glucans in biomass will serve as an enabling technology for developments towards efficient use of plant-derived materials and biomass. [GRAPHICS] .

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  • 231.
    Chubarova, Elena V.
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik, Biomedicinsk fysik och röntgenfysik. Jacobs Univ, Sch Sci & Engn, Germany.
    Dickman, M. H.
    Keita, B.
    Nadjo, L.
    Miserque, F.
    Mifsud, M.
    Arends, I. W. C. E.
    Kortz, U.
    Self-assembly of a heteropolyoxopalladate nanocube: [PdII 13AsV 8O34(OH)6] 8-2008Inngår i: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 47, nr 49, s. 9542-9546Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    (Chemical Equation Presented) Not like the others: A molecular palladium oxide cluster was formed by self-assembly of palladium(II) and arsenic(V) using mild reaction conditions. The resulting heteropolypalladate [Pd II 13AsV 8O34(OH) 6]8- has a distorted cubic shape and edge lengths of about 1 nm. The thirteen PdII ions retain four-coordinate square-planar geometry, in marked contrast to all other known discrete polyoxometalates.

  • 232.
    Chudasama, Nishith A.
    et al.
    Charotar Univ Sci & Technol, PD Patel Inst Appl Sci, Changa 388421, India.;CSIR Cent Salt & Marine Chem Res Inst, Nat Prod & Green Chem Div, GB Marg, Bhavnagar 364002, Gujarat, India..
    Polisetti, Veerababu
    CSIR Cent Salt & Marine Chem Res Inst, Membrane Sci & Separat Technol Div, GB Marg, Bhavnagar 364002, Gujarat, India..
    Maity, Tapan Kumar
    CSIR Cent Salt & Marine Chem Res Inst, Nat Prod & Green Chem Div, GB Marg, Bhavnagar 364002, Gujarat, India.;Acad Sci & Innovat Res AcSIR, Ghaziabad 201002, India..
    Reddy, A. V. R.
    CSIR Cent Salt & Marine Chem Res Inst, Membrane Sci & Separat Technol Div, GB Marg, Bhavnagar 364002, Gujarat, India..
    Prasad, Kamalesh
    CSIR Cent Salt & Marine Chem Res Inst, Nat Prod & Green Chem Div, GB Marg, Bhavnagar 364002, Gujarat, India.;Acad Sci & Innovat Res AcSIR, Ghaziabad 201002, India..
    Preparation of seaweed polysaccharide based hydrophobic composite membranes for the separation of oil/water emulsion and protein2022Inngår i: International Journal of Biological Macromolecules, ISSN 0141-8130, E-ISSN 1879-0003, Vol. 199, s. 36-41Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Agarose is a seaweed-based polysaccharide and is widely used for the separation of nucleic acids in molecular biology. Cross-linked agarose beads are also used as solid-phase matrices in size exclusion chromatography for the separation of proteins. To find the application of agarose for the separation of oil/water emulsion and protein, herein hydrophobic derivative of the seaweed biopolymer [M-W (1.27 +/- 0.17) x 10(-5) g/mol; sulphate content (0.29 +/- 0.09) %, gel strength (2242 +/- 21) g/cm(2)] is prepared by reacting the biopolymer with stearic acid and was used to prepare a composite membrane on polyester fabric. The oil and BSA rejection performance of the composite membrane was greater than 98%. The rejection rate increased with the increase in polymer content in the respective membranes for both oil/water and protein separation. The composite membrane showed a stable oil/water emulsion and protein separation performance over a period of six hours. Due to the biodegradable nature of the major components of the membrane, it has the potential for industrial applications.

  • 233.
    Cirera, Borja
    et al.
    IMDEA Nanosci, Spain.
    Trukhina, Olga
    University of Autonoma Madrid, Spain.
    Björk, Jonas
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Teoretisk Fysik. Linköpings universitet, Tekniska fakulteten.
    Bottari, Giovanni
    IMDEA Nanosci, Spain; University of Autonoma Madrid, Spain; University of Autonoma Madrid, Spain.
    Rodriguez-Fernandez, Jonathan
    University of Autonoma Madrid, Spain.
    Martin-Jimenez, Alberto
    IMDEA Nanosci, Spain.
    Islyaikin, Mikhail K.
    Ivanovo State University of Chemistry and Technology, Russia.
    Otero, Roberto
    IMDEA Nanosci, Spain; University of Autonoma Madrid, Spain.
    Gallego, Jose M.
    CSIC, Spain.
    Miranda, Rodolfo
    IMDEA Nanosci, Spain; University of Autonoma Madrid, Spain.
    Torres, Tomas
    IMDEA Nanosci, Spain; University of Autonoma Madrid, Spain; University of Autonoma Madrid, Spain.
    Ecija, David
    IMDEA Nanosci, Spain.
    Long-Range Orientational Self-Assembly, Spatially Controlled Deprotonation, and Off-Centered Metalation of an Expanded Porphyrin2017Inngår i: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 139, nr 40, s. 14129-14136Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Expanded porphyrins are large-cavity macro cycles with enormous potential in coordination chemistry, anion sensing, photodynamic therapy, and optoelectronics. In the last two decades, the surface science community has assessed the physicochemical properties of tetrapyrrolic-like macrocydes. However, to date, the sublimation, self-assembly and atomistic insights of expanded porphyrins on surfaces have remained elusive. Here, we show the self-assembly on Au(111) of an expanded aza-porphyrin, namely, an "expanded hemi-spatially-controlled porphyrazine", through a unique growth mechanism based on deprotonation long-range orientational self-assembly. Furthermore, a spatially controlled "writing" protocol on such self-assembled architecture is presented based on the STM tip-induced deprotonation of the inner protons of individual macrocydes. Finally, the capability of these surface-confined macrocydes to host lanthanide elements is assessed, introducing a novel off-centered coordination motif. The presented findings represent a milestone in the fields of porphyrinoid chemistry and surface science, revealing a great potential for novel surface patterning, opening new avenues for molecular level information storage, and boosting the emerging field of surface-confined coordination chemistry involving f-block elements.

  • 234.
    Claesson, Per
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Yt- och korrosionsvetenskap.
    Dédinaité, Andra
    KTH, Skolan för kemivetenskap (CHE), Kemi, Yt- och korrosionsvetenskap.
    Meszaros, R.
    Varga, Imre
    Association between Polyelectrolytes and Oppositely Charged Surfactants in Bulk and at Solid/Liquid Interfaces2007Inngår i: Colloid Stability and Application in Pharmacy: Volume 3, Weinheim: Wiley-VCH Verlagsgesellschaft, 2007, s. 337-395Kapittel i bok, del av antologi (Annet vitenskapelig)
    Abstract [en]

    Mixtures of polyelectrolytes and oppositely charged surfactants find applications in many processes and products that are used in our daily life. Such systems also show many interesting features from a scientific point of view. Due to the combined technological relevance and scientific challenge, considerable research efforts have been made in this area in recent years. This has resulted in new theoretical approaches, the development of simulation methods and new experimental techniques and, of course, a large body of new findings. Together, these efforts have increased the understanding significantly, especially during the last 5 years. This chapter reviews some aspects of this topic, focusing on bulk association and association at solid/liquid interfaces. The review is focused on developments during the 21st century, even though in some cases a historical perspective is also offered.

  • 235.
    Claesson, Per
    et al.
    KTH, Tidigare Institutioner (före 2005), Kemi.
    Poptochev, Evgeni
    KTH, Tidigare Institutioner (före 2005), Kemi.
    Blomberg, Eva
    KTH, Tidigare Institutioner (före 2005), Kemi.
    Surface Forces and Emulsion Stability2004Inngår i: Food Emulsions / [ed] Sjöblom, J., Friberg, S. and Larsson, K., New York: Marcel Dekker, 2004, 4, s. 257-297Kapittel i bok, del av antologi (Annet vitenskapelig)
  • 236.
    Claesson, Per
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Yt- och korrosionsvetenskap.
    Stubenrausch, C
    Krustev, R
    Johansson, I
    Thin Film and Foam Properties of Sugar-Based Surfactants2009Inngår i: Sugar-Based Surfactants: Fundamentals and Applications / [ed] Ruiz, Cristóbal Carnero, Boca Raton: Taylor & Francis Group, 2009, s. 105-152Kapittel i bok, del av antologi (Annet vitenskapelig)
  • 237.
    Claesson, Per
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Yt- och korrosionsvetenskap.
    van der Wal, Andreas
    KTH, Skolan för kemivetenskap (CHE), Kemi, Yt- och korrosionsvetenskap.
    Fogden, Andrew
    KTH, Skolan för kemivetenskap (CHE), Kemi, Yt- och korrosionsvetenskap.
    New Techniques for Optimization of Particulate Cleaning2007Inngår i: Handbook for Cleaning/Decontamination of Surfaces Vol 2 / [ed] I. Johansson, and P. Somasundaran, Amsterdam: Elsevier, 2007, s. 885-927Kapittel i bok, del av antologi (Annet vitenskapelig)
  • 238.
    Corkery, Robert W.
    Procter and Gamble, Ross, Ohio, USA.
    A variation on Luzzati's soap phases: Room temperature thermotropic liquid crystals2004Inngår i: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 6, nr 7, s. 1534-1546Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Remarkable room-temp. liq. crystallinity is obsd. for a wide range of metal soaps. Incorporation of satd., mid-chain mono-Me branched C17 fatty acid (mid-chain branched fatty acid) into metal soaps lowers the liq. cryst. transition to below room temp. Soaps of Na, Mg, Al, Ca, Cu, Zn, Sr, Ag, Cd, La, Ce, Tb and Lu were synthesized and characterized via XRD, FTIR, DSC, optical microscopy, d. detns. and other phys. methods. The main room temp. mesophase identified in the soaps here is a liq. cryst. hexagonal columnar phase, 1st described by Luzzati et al. A comparative anal. of the branched soaps with their satd., linear analogs is given. Implications for room temp. columnar soap structure is discussed in terms of the various phys. parameters found for these soaps.

  • 239.
    Corkery, Robert W.
    YKI, Institute for Surface Chemistry, Stockholm, Sweden.
    Aspects of the differential geometry and topology of bicontinuous liquid-crystalline phases2005Inngår i: Surfactant Sci. Ser., ISSN 0081-9603, Vol. 127, nr Bicontinuous Liquid Crystals, s. 99-127Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A review. This chapter provides a semiformal, though largely qual., look at the mathematics of triply periodic minimal surfaces (TPMS) in relation to bicontinuous and polycontinuous liq. crystals. It is motivated largely by research of Stephen Hyde and others at the Applied Mathematics Department, Australian National University, Canberra, Australia and by the discovery of these TPMS liq. crystal partitions by Kare Larsson and the late Krister Fontell at Lund University. The article is meant to complement the existing, more rigorous papers and provide an introduction to the more fundamental topics of differential geometry and topol. of TPMS. Bicontinuous liq. crystals contain 2 mutually interpenetrating labyrinths sepd. by a hyperbolic partition that is often best described as a triply periodic minimal surface (TPMS). Properties of these surfaces can be broken down into local and global types. Local properties pertain to small, isolated surface patches and include intrinsic measures such as the metric, surface areas, and angles and the Gaussian curvature. The global properties require a look at the surface as a whole, embedded in 3D space. The global measures include parameters such as the Cartesian coordinates, topol., curvature distributions, and overall symmetries. These local and global properties are connected through the Gauss-Bonnet theorem that relates the topol. to the Gaussian curvature. For the simplest TPMS, such as the P, D, and G surfaces, the local Gaussian curvature detd. from small patches of the surface can give information regarding the stability of bicontinuous liq. crystals. For some simpler TPMS, the small surface patches are polygonal (e.g., triangles), according to the various symmetries of the surface. These small 2D surface patches can be built up into the entire 3D surface using various 3D construction algorithms based on symmetries, the same way 3D crystals can be built up from unique atoms. Alternatively these patches can be usefully represented in 2 dimensions by various mappings to the sphere, hyperbolic plane, and complex plane; then built up in those spaces using analogous symmetry operations; and then embedded in 3D space by folding and "gluing" the edges of the 2D representations. The 2D forms of these surfaces offer simple ways of constructing known and novel surfaces, algorithmically, and also explicitly through the Weierstrass parametrization, which gives the exact and explicit (x,y,z) coordinates of the actual minimal surface (not approximates) via the complex plane representation. Armed with this explicit information, modeling the stabilities, phase changes, and other phys. processes involving these minimal surfaces is rigorously quantifiable from a geometric perspective. A novel, topol.-preserving phase transformation between the P, D, and G cubic phases arises directly from the anal. of rhombohedral and tetrahedral distortions of the P, D, and G surfaces using this method. Networks decorating TPMS are of interest for generating and analyzing crystal networks. The simplest networks overlay the polygonally decorated surfaces built up of the fundamental patches. Families of networks can be generated for individual TPMS using supergroup-subgroup symmetry relationships between the decorating tesselation and the underlying symmetry elements of the TPMS itself. Of direct relevance to liq. cryst. mesophases is the set of polycontinuous networks that can be generated on various TPMS. These are generated by commensurately decorating 2D surface representations of TPMS with tree networks. With some well-chosen constraints, folding and gluing operations can result in surfaces decorated by entangled thickets of unconnected networks. In turn, these embedded networks can be used to form tri-, quadra-, octa- and other polycontinuous morphologies, with their resp. mutually interpenetrating labyrinths sepd. by a single triply periodic minimal surface.

  • 240.
    Corkery, Robert W.
    Applied Mathematics Research School of Physical Sciences and Engineering Australian National University, Canberra, Australia.
    Metal organic framework (MOF) liquid crystals: 1D, 2D and 3D ionic coordination polymer structures in the thermotropic mesophases of metal soaps, including alkaline earth, transition metal and lanthanide soaps2008Inngår i: Current Opinion in Colloid & Interface Science, ISSN 1359-0294, E-ISSN 1879-0399, Vol. 13, nr 4, s. 288-302Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    aken together, the body of existing literature on metal soap crystal structures and mesophases supports the view that much is to be gained by treating the soaps as metal organic frameworks (MOF's) when relating their structure and liquid crystallinity. We argue that metal soaps mesophases often consist of disordered metal organic (carboxylate) frameworks (MOF's). Metal atoms are linked by bridging carboxylates, and the metal-oxygen networks form semi-flexible rods, chains and sheets of M-O polyhedra within their co-bonded, mesotructured, self-assemblies of lipidic chains. The packing of the molten hydrocarbon chains allows otherwise unconnected MOF networks to coexist as spatially isolated units in the same unit cell. For instance the lamellar phases are true 2D MOF's or layers of 1-D MOF's. The phase transitions can then be regarded as coupled disordering/re-ordering transitions involving rotational and conformational disordering of the hydrocarbon chains balanced with disordering of MOF symmetries, MOF topological transformations, depolymerizations and dimensionality reductions ultimately leading to anisotropic melts. By way of demonstration, thermotropic phase transitions of homologous series of lanthanide soaps are systematically studied using a variety of experimental methods, and the data are used in a topological model for testing the consistency with the MOF concept of metal soap crystal structures and thermotropic: mesophases. Finally, an interpenetrating bicontinuous MOF comprised of SrO6 polyhedral rods is presented as an atomically resolved model for the network topology of the cubic mesophase of strontium soaps. Metal soaps are therefore shown to afford a bridge between liquid crystals and metal organic framework (MOF) materials. 

  • 241.
    Corkery, Robert W.
    et al.
    YKI, Institute for Surface Chemistry, Stockholm, Sweden.
    Blute, Irena A.
    YKI, Institute for Surface Chemistry, Stockholm, Sweden.
    Friberg, Stig E.
    School of Chemistry and Chemical Engineering, Yangzhou University.
    Guo, Rong
    School of Chemistry and Chemical Engineering, Yangzhou University.
    Emulsion Inversion in the PIT Range: Quantitative Phase Variations in a Two-Phase Emulsion2010Inngår i: Journal of Chemical and Engineering Data, ISSN 0021-9568, E-ISSN 1520-5134, Vol. 55, nr 10, s. 4471-4475Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The phase-inversion temperature (PIT) phenomenon is for the first time given l quantitative treatment for systems having a sufficiently small surfactant content to be limited to two phases at the PIT. The results show that the early opinion of a phase transfer of the surfactant as the major event in the transversal of the temperature range is not entirely correct; the major phenomenon is instead an expulsion of water from the low-temperature aqueous micellar solution. In addition, the results unexpectedly give an indication of the existence of three phases at temperatures beneath the PIT, in spite of the the fact that system consists of only two phases at the actual PIT.

  • 242.
    Corkery, Robert W.
    et al.
    Frito Lay North America INC.
    Feiler, Adam
    Grover, Julie Anne
    Dimelow, Chris
    George, Eapen
    Anti-caking agent for flavored products2010Patent (Annet (populærvitenskap, debatt, mm))
    Abstract [en]

    The present invention generally relates to the use of porous particles to control the release of a liquid, such as the release of a flavor in a food product. Liquid components, such as flavorants, are loaded into porous particles to form a composition. The pore diameter, pore tortuosity and loading parameters determine the characteristics of the composition and the release profile of the liquid.

  • 243.
    Corkery, Robert W.
    et al.
    Naturalnano INC.
    Fleischer, Cathy
    Naturalnano INC.
    Polymeric coatings including nanoparticle filler2007Patent (Annet (populærvitenskap, debatt, mm))
    Abstract [en]

    Disclosed is a polymeric composite coating including a nanoparticle filler, where the filler may be suitable to alter one or more characteristics of the coating. More particularly, one embodiment of the present invention provides a halloysite nanoparticle filler which has the general configuration of a cylinder or a rolled scroll-like shape, and a polymer protective coating contg. the halloysite nanoparticle or equiv. nanotubular filler. [on SciFinder(R)]

  • 244.
    Corkery, Robert W.
    et al.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Yt- och korrosionsvetenskap. KTH, Skolan för kemivetenskap (CHE), Kemi, Fysikalisk kemi.
    Fleischer, Cathy
    Daly, Robert C.
    Polymeric composition, adhesive including nanoparticle filler and composite production.2006Patent (Annet (populærvitenskap, debatt, mm))
    Abstract [en]

    Nanoparticle fillers, including a novel halloysite nanoparticle filler, are generally cylindrical or tubular nanoparticles (e.g. rolled scroll-like shape). The filler is effectively employed in a polymer nanoparticle adhesive composite, contg. the halloysite nanoparticle or other equiv. naturally occurring nanotubular filler, in which the advantages of the nanoparticle filler are provided (e.g., reinforcement, flame retardant, etc.) while maintaining or improving mech. performance of the adhesive composite (e.g., adhesive strength and tack). [on SciFinder(R)]

  • 245.
    Corkery, Robert W
    et al.
    Physical Chemistry 1, Center for Chemistry and Chemical Engineering, Lund University.
    Fogden, Andrew
    Physical Chemistry 1, Center for Chemistry and Chemical Engineering, Lund University.
    On the formation and structure of nanometric polyhedral foams: toward the dry limit2008Inngår i: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 24, nr 18, s. 10443-10452Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    High surface area, high porosity, nanometric polygonal silica foams with hierarchically connected and uniformly sized pore systems are reported here. We observe a remarkable increase in foam cell sizes from mesoscopic to macroscopic dimensions upon swelling the self-assembled template with oil. The resultant structures resemble classical macroscopic soap foams and display, among other features, Plateau borders and volume fractions approaching the dry limit of 100%. In well-developed foams of this kind, dimensionally isometric polyhedral cells are connected by relatively short, flat cylindrical mesopores through polyhedral faces and micropores through the walls. For one sample, with approximately 75 nm diameter primary foam cells, we infer three separate sets of cell-connecting mesopores puncturing tetragonal, pentagonal, and hexagonal faces of the component polyhedra. A multiple step model of foam formation is discussed where an organic silica precursor progressively hydrolyzes and condenses as a growing flexible shell from the core-corona interface of oil-swollen triblock copolymer micelles or microemulsion droplets, inducing a clouding phenomena in the otherwise stabilizing poly(ethylene oxide) chains, leading to aggregation, deformation, and jamming to high volume fractions.

  • 246.
    Corkery, Robert W.
    et al.
    YKI, Institute for Surface Chemistry, Stockholm, Sweden.
    Rousseau, Derick
    chool of Nutrition, Ryerson University, Toronto, Ontario, Canada.
    Smith, Paul
    YKI, Institute for Surface Chemistry, Stockholm, Sweden.
    Pink, David A.
    Department of Physics, St. Francis Xavier University, Antigonish, Nova Scotia, Canada.
    Hanna, Charles B.
    Canada, and Department of Physics, Boise State University, Boise, Idaho, USA.
    A case for discotic liquid crystals in molten triglycerides2007Inngår i: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 23, nr 13, s. 7241-7246Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    To date, essentially only two structural models have been proposed and debated in detail for explaining the liquid state order of triglycerides, and both invoke a form of thermotropic liquid crystalline order in triglyceride melts. These are the paralamellar model of Larsson et al. (J. Am. Oil Chem. Soc. 1992, 69, 835) and the nematic model of Cebula et al. (J. Am. Oil Chem Soc. 1992, 69, 130). An alternative discotic model is proposed here that adequately accounts for the broad small-angle X-ray diffraction peak often observed in the liquid state of fats and oils. In this alternative model, triglyceride molecules exist in the liquid state with fully splayed chains, approximating "Y"-shapes (Y-conformers). These are loosely bound within discs that stack into flexible, relatively short cylindrical rods of colloidal dimension, which in turn assemble into rod-packings with short-range order akin to disordered versions of thermotropic discotic liquid crystalline phases in other lipidic systems.

  • 247. Cronholm, Pontus
    et al.
    Karlsson, Hanna L.
    Hedberg, Jonas
    KTH, Skolan för kemivetenskap (CHE), Kemi, Yt- och korrosionsvetenskap.
    Lowe, Troy A.
    KTH, Skolan för kemivetenskap (CHE), Kemi, Yt- och korrosionsvetenskap.
    Winnberg, Lina
    Elihn, Karine
    Odnevall Wallinder, Inger
    KTH, Skolan för kemivetenskap (CHE), Kemi, Yt- och korrosionsvetenskap.
    Möller, Lennart
    Intracellular Uptake and Toxicity of Ag and CuO Nanoparticles: A Comparison Between Nanoparticles and their Corresponding Metal Ions2013Inngår i: Small, ISSN 1613-6810, E-ISSN 1613-6829, Vol. 9, nr 7, s. 970-982Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An increased understanding of nanoparticle toxicity and its impact on human health is essential to enable a safe use of nanoparticles in our society. The aim of this study is to investigate the role of a Trojan horse type mechanism for the toxicity of Ag-nano and CuO-nano particles and their corresponding metal ionic species (using CuCl2 and AgNO3), i.e., the importance of the solid particle to mediate cellular uptake and subsequent release of toxic species inside the cell. The human lung cell lines A549 and BEAS-2B are used and cell death/membrane integrity and DNA damage are investigated by means of trypan blue staining and the comet assay, respectively. Chemical analysis of the cellular dose of copper and silver is performed using atomic absorption spectroscopy. Furthermore, transmission electron microscopy, laser scanning confocal microscopy, and confocal Raman microscopy are employed to study cellular uptake and particle-cell interactions. The results confirm a high uptake of CuO-nano and Ag-nano compared to no, or low, uptake of the soluble salts. CuO-nano induces both cell death and DNA damage whereas CuCl2 induces no toxicity. The opposite is observed for silver, where Ag-nano does not cause any toxicity, whereas AgNO3 induces a high level of cell death. In conclusion: CuO-nano toxicity is predominantly mediated by intracellular uptake and subsequent release of copper ions, whereas no toxicity is observed for Ag-nano due to low release of silver ions within short time periods.

  • 248.
    Crouzier, Thomas
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Glykovetenskap. Cirqle Biomedical Contraception ApS, Copenhagen, Denmark; AIMES—Center for the Advancement of Integrated Medical and Engineering Sciences, Karolinska Institutet and KTH Royal Institute of Technology, Stockholm, Sweden; Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden.
    A defensive blanket against viral infection of the lungs2023Inngår i: Nature Materials, ISSN 1476-1122, E-ISSN 1476-4660, Vol. 22, nr 7, s. 803-804Artikkel i tidsskrift (Fagfellevurdert)
  • 249.
    Cullari, Lucas Luciano
    et al.
    Department of Chemical Engineering, Ben-Gurion University of the Negev, Beer-Sheva 8410501, Israel.
    Yosefi, Gal
    Department of Chemical Engineering, Ben-Gurion University of the Negev, Beer-Sheva 8410501, Israel.
    Nativ-Roth, Einat
    The Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beer-Sheva 8410501, Israel.
    Furo, Istvan
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi.
    Regev, Oren
    Department of Chemical Engineering, Ben-Gurion University of the Negev, Beer-Sheva 8410501, Israel; The Ilse Katz Institute for Nanoscale Science and Technology, Ben-Gurion University of the Negev, Beer-Sheva 8410501, Israel.
    Decoupling rheology from particle concentration by charge modulation: Aqueous graphene-clay dispersions2024Inngår i: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 655, s. 863-875Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Hypothesis: Aqueous graphene dispersions are usually obtainable by treating the surface of graphene chemically or physically. In these dispersions, the rheological properties (e.g., viscosity) are governed by a direct coupling to the graphene concentration, which limits their applicability. An alternative approach for dispersing graphene is trapping them in a viscoelastic-network formed by a co-dispersed charged fibrous-clay, Sepiolite. Contrary to surface treatment, the rheological properties of these dispersions are set by the clay particles. The rheology of charged-colloidal dispersions is governed by various parameters, including interparticle interactions. Hence, the rheology of the dispersion could be modulated by changing the clay surface charge without compromising the dispersed graphene concentration. Experimental: The surface charge of Sepiolite was modulated either by charge-screening (by NaCl added to the solution) or by surface-charging (by attachment of highly charged ions, e.g., HexaMetaPhosphate, HMP−) and the effect on rheology and graphene concentration was assessed. In particular, loading the dispersion with HMP− yielded low viscosity, storage, and loss moduli (two orders of magnitude lower than the corresponding HMP−-free dispersion) while the graphene concentration was maintained. We demonstrate that by this charge-modulation approach, reaching the rheological requirements of different applications without compromising on graphene concentration is plausible.

  • 250. Céolin, D.
    et al.
    Rueff, J. -P
    Zimin, Andrei
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi. Siberian Federal University, Russian Federation.
    Morin, P.
    Kimberg, Victor
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi. Siberian Federal University, Russian Federation.
    Polyutov, S.
    Ågren, Hans
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi. Siberian Federal University, Russian Federation.
    Gelmukhanov, Faris
    KTH, Skolan för bioteknologi (BIO), Teoretisk kemi och biologi. Siberian Federal University, Russian Federation.
    Far-Zone Resonant Energy Transfer in X-ray Photoemission as a Structure Determination Tool2017Inngår i: Journal of Physical Chemistry Letters, ISSN 1948-7185, E-ISSN 1948-7185, Vol. 8, nr 12, s. 2730-2734Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Near-zone Förster resonant energy transfer is the main effect responsible for excitation energy flow in the optical region and is frequently used to obtain structural information. In the hard X-ray region, the Förster law is inadequate because the wavelength is generally shorter than the distance between donors and acceptors; hence, far-zone resonant energy transfer (FZRET) becomes dominant. We demonstrate the characteristics of X-ray FZRET and its fundamental differences with the ordinary near-zone resonant energy-transfer process in the optical region by recording and analyzing two qualitatively different systems: high-density CuO polycrystalline powder and SF6 diluted gas. We suggest a method to estimate geometrical structure using X-ray FZRET employing as a ruler the distance-dependent shift of the acceptor core ionization potential induced by the Coulomb field of the core-ionized donor.

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