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A new approach for preparation of multifunctional polymers with pendant vinyl ethers was investigated. In particular, 2-(1-propenyl)oxyethyl methacrylate, a new ambifunctional monomer combining easy radical polymerization and a fast cationically cross-linkable group, was evaluated. Hence, the physical characteristics of copolymers were controlled by the selection of comonomers. Cross-linking kinetics as a function of temperature and concentration of the acid-generating species were monitored quantitatively by FT-IR spectroscopy. Through the use of DSC measurements, the onset for cationic polymerization was determined. It was demonstrated that both 9-fluorenylideneimino-p-toluenesulfonate and diphenyliodonium triflate could be used as efficient thermally initiating cross-linking agents.

Co- and terpolycarbonates containing thermosensitive cycloallylic, benzylic or tertiary diols and, in addition, labile azo functionalities were synthesized in solution from bis(imidazole-carboxylate)s under phase-transfer conditions. The azo groups were introduced by using 2,2'azobis(2-methylpropanol) (1) and azobis(1-hydroxymethyl)cyclohexane (2) as diol components. All copolymers were obtained as amorphous, soft materials with glass transition temperatures below 30°C. Partial crystallinity, however, could be obtained in terpolycarbonates, leading to improved mechanical stability of the products. The polymers were obtained with molar masses Mn in the range 6000-12 900 g/mol. Depending on the structure, the polymers decomposed between 180 and 220°C in a clean, fast, and exothermic process, liberating mostly volatile products. The thermal lability of the azo moieties 1 and 2 was similar to that of the labile carbonate units. In the presence of acids, the thermal stability was drastically reduced and the de...

Polymeric azosulfonates lose their water solubility when exposed to UV light due to decomposition of the azo function. This effect can be used in water-based photoprinting processes. Water-soluble copolymers of azosulfonate containing repeat units and methyl methacrylate have been alternatively synthesized by a polymer-analogous reaction [1,2] and by direct copolymerization [3]. Both polymer types have been evaluated for application as photoresins in offset printing processes. The polymer made by copolymerization is superior and shows excellent results for photosensitivity, resolution, film-forming properties, and development in water, as well as for thermal and moisture storage stability.

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An economical method of coating organic-polymeric carrier materials with at least one film and tempering the thus coated materials, wherein the carrier material has a thickness of at least 60 mu m and consists of a polymeric material with a glass transition temperature of at least 90 DEG C, the applied film has a thickness of a maximum of 30 mu m, the coating is performed at temperatures below the glass transition temperature and the tempering is performed at temperatures of at least 250 DEG C by means of a plasma.

A non-dye containing flexographic ink containing a polymer or copolymer of a 3,4-dialkoxythiophene in which the two alkoxy groups may be the same or different or together represent an optionally substituted oxy-alkylene-oxy bridge, a polyanion and a latex binder in a solvent or aqueous medium, characterized in that the polymer or copolymer of a 3,4-dialkoxythiophene is present in a concentration of at least 0.1% by weight in the ink and that the ink is capable of producing a colorimetrically additive transparent print; a method of preparing the flexographic ink; and a flexographic printing process therewith.

An image processing method comprises a step of converting halftoned pixels of an image to be printed represented at a first lower tonal resolution into pixels represented at a second higher tonal resolution. Image processing is used on said pixels having a higher tonal resolution to reduce image quality artifacts when said pixels are printed at said first lower tonal resolution. In a preferred embodiment, the image processing comprises error diffusion of a sigma delta modulation.

Urban catchments are typically characterised by high spatial variability and fast runoff processes resulting in short response times. Hydrological analysis of such catchments requires high resolution precipitation and catchment information to properly represent catchment response. This study investigated the impact of rainfall input resolution on the outputs of detailed hydrodynamic models of seven urban catchments in North-West Europe. The aim was to identify critical rainfall resolutions for urban catchments to properly characterise catchment response. Nine storm events measured by a dual-polarimetric X-band weather radar, located in the Cabauw Experimental Site for Atmospheric Research (CESAR) of the Netherlands, were selected for analysis. Based on the original radar estimates, at 100 m and 1 min resolutions, 15 different combinations of coarser spatial and temporal resolutions, up to 3000 m and 10 min, were generated. These estimates were then applied to the operational semi-distributed hydrodynamic models of the urban catchments, all of which have similar size (between 3 and 8 km2), but different morphological, hydrological and hydraulic characteristics. When doing so, methodologies for standardising model outputs and making results comparable were implemented. Results were analysed in the light of storm and catchment characteristics. Three main features were observed in the results: (1) the impact of rainfall input resolution decreases rapidly as catchment drainage area increases; (2) in general, variations in temporal resolution of rainfall inputs affect hydrodynamic modelling results more strongly than variations in spatial resolution; (3) there is a strong interaction between the spatial and temporal resolution of rainfall input estimates. Based upon these results, methods to quantify the impact of rainfall input resolution as a function of catchment size and spatial–temporal characteristics of storms are proposed and discussed. publisher: Elsevier articletitle: Impact of spatial and temporal resolution of rainfall inputs on urban hydrodynamic modelling outputs: A multi-catchment investigation journaltitle: Journal of Hydrology articlelink: http://dx.doi.org/10.1016/j.jhydrol.2015.05.035 content_type: article copyright: Copyright © 2015 The Authors. Published by Elsevier B.V. ispartof: Journal of Hydrology vol:531 issue:2 pages:389-407 status: published

Zn1-xCuxAl2O4 (0or = x0.30) compounds have been synthesized by polyesterification using metallic salts and annealing at low temperatures as well as by conventional solid state. XRD-powder data refinements (Rietveld method) have demonstrated that both compound series crystallize in the spinel structure (Fd3m) and exhibit similar inversion rates. This low-temperature route lead to metastable phases with crystallite sizes around 40 nm whereas particle sizes are larger than 1 moicrom in the case of solid-state route. This preparative method largely described in the literature allows stabilizing reduced copper states thanks to the presence of reductive organic species, which are decomposed below T = 700 degrees C. The absorption spectra of the x = 0.15 composition exhibit strong differences depending on the synthesis route. These differences can be explained by the occurrence of Cu2+/Cu+ mixed valencies in compounds prepared by the low-temperature route; 33% of monovalent copper has been identified in the x = 0.15 composition prepared by low-temperature process, whereas the solid-state compound contains only divalent copper. Reductive properties of polyesterification reaction implying citric acid and low annealing temperature (T = 700 degrees C) are mainly responsible of the occurrence of the Cu2+/Cu+ mixed valencies. Actually, the annealing under air at T = 1000 degrees C of divided zinc-copper aluminates prepared at low temperatures (T = 700 degrees C) leads to the oxidation reaction Cu+ --Cu2+ + e- confirmed by the evolution of magnetic measurements, ESR spectra, and optical absorption properties. Defects such as oxygen vacancies in the anionic network leading to reduction in the cations coordination number could also explain the strong evolution of optical absorption spectra especially around lambda = 700 nm where intervalencies transfer (Cu+/Cu2+) as well as intra-atomic d-d transitions (Cu2+ in a 5-fold coordination) can occur. Finally the occurrence of monovalent and divalent copper at the surface of such divided oxides, probably in tetrahedral sites, has been demonstrated by FTIR spectroscopy using the co-adsorption of CO and NO as probe molecules.

The present work is the fourth (and final) contribution to an inter-laboratory collaboration that was planned at the 3rd International Summit on Organic Photovoltaic Stability (ISOS-3). The collaboration involved six laboratories capable of producing seven distinct sets of OPV devices that were degraded under well-defined conditions in accordance with the ISOS-3 protocols. The degradation experiments lasted up to 1830 hours and involved more than 300 cells on more than 100 devices. The devices were analyzed and characterized at different points of their lifetimes by a large number of non-destructive and destructive techniques in order to identify specific degradation mechanisms responsible for the deterioration of the photovoltaic response. Work presented herein involves time-of-flight secondary ion mass spectrometry (TOF-SIMS) in order to study chemical degradation in-plane as well as in-depth in the organic solar cells. Various degradation mechanisms were investigated and correlated with cell performance. For example, photo-oxidation of the active material was quantitatively studied as a function of cell performance. The large variety of cell architectures used (some with and some without encapsulation) enabled valuable comparisons and important conclusions to be drawn on degradation behaviour. This comprehensive investigation of OPV stability has significantly advanced the understanding of degradation behaviour in OPV devices, which is an important step towards large scale application of organic solar cells. © 2012 the Owner Societies., This work has been supported by the Danish Strategic Research Council (2104-07-0022), EUDP (j.no. 64009-0050, 64009-0051) and the Danish National Research Foundation. Partial financial support was also received from the European Commission as part of the Framework 7 ICT 2009 collaborative project HIFLEX (grant no. 248678), partial financial support from the EUIndian framework of the ‘‘Largecells’’ project that received funding from the European Commission’s Seventh Framework Programme (FP7/2007–2013. grant no. 261936), partial financial support was also received from the European Commission as part of the Framework 7 ICT 2009 collaborative project ROTROT (grant no. 288565) and from PVERA-NET (project acronym POLYSTAR). are due to CONACYT (México) for the PhD scholarship awarded to G. T.-E; to the Spanish Ministry of Science and Innovation, MICINN-FEDER project ENE2008-04373; to the Consolider NANOSELECT project CSD2007-00041; to the Xarxa de Referència en Materials Avançats per a l’Energia, XaRMAE of the Catalonia Government (Spain). RR and HH are grateful for financial support from the Thuringian Ministry of Culture and the German Federal Ministry of Education and Research in the frameworks of FIPV II and PPP (contract number 13N9843), respectively. DMT acknowledges generous support from the Inger and Jens Bruun Foundation through The American-Scandinavian Foundation.

This work is part of the inter-laboratory collaboration to study the stability of seven distinct sets of state-of-the-art organic photovoltaic (OPV) devices prepared by leading research laboratories. All devices have been shipped to and degraded at RISO-DTU up to 1830 hours in accordance with established ISOS-3 protocols under defined illumination conditions. In this work, we apply the Incident Photon-to-Electron Conversion Efficiency (IPCE) and the in situ IPCE techniques to determine the relation between solar cell performance and solar cell stability. Different ageing conditions were considered: accelerated full sun simulation, low level indoor fluorescent lighting and dark storage. The devices were also monitored under conditions of ambient and inert (N 2) atmospheres, which allows for the identification of the solar cell materials more susceptible to degradation by ambient air (oxygen and moisture). The different OPVs configurations permitted the study of the intrinsic stability of the devices depending on: two different ITO-replacement alternatives, two different hole extraction layers (PEDOT:PSS and MoO 3), and two different P3HT-based polymers. The response of un-encapsulated devices to ambient atmosphere offered insight into the importance of moisture in solar cell performance. Our results demonstrate that the IPCE and the in situ IPCE techniques are valuable analytical methods to understand device degradation and solar cell lifetime. © 2012 the Owner Societies., This work has been supported by the Danish Strategic Research Council (2104-07-0022), EUDP (j.no. 64009-0050), and the Danish National Research Foundation. Partial financial support was also received from the European Commission as part of the Framework 7 ICT 2009 collaborative project HIFLEX (grant no. 248678), partial financial support from the EUIndian framework of the ‘‘Largecells’’ project that received funding from the European Commission’s Seventh Framework Programme (FP7/2007–2013. grant no. 261936), partial financial support was also received from the European Commission as part of the Framework 7 ICT 2009 collaborative project ROTROT (grant no. 288565) and from PVERA-NET (project acronym POLYSTAR). To CONACYT (México) for the Ph.D. scholarship awarded to G. T.-E, to the Spanish Ministry of Science and Innovation, MICINN-FEDER project ENE2008-04373, to the Consolider NANOSELECT project CSD2007-00041, to the Xarxa de Referència en Materials Avançats per a l’Energia, XaRMAE of the Catalonia Government (Spain). RR and HH are grateful for financial support from the Thuringian Ministry of Culture and the German Federal Ministry of Education and Research in the frameworks of FIPV II and PPP (contract number 13N9843), respectively. DMT acknowledges generous support from the Inger and Jens Bruun Foundation through The American–Scandinavian Foundation.

The investigation of degradation of seven distinct sets (with a number of individual cells of n ≥ 12) of state of the art organic photovoltaic devices prepared by leading research laboratories with a combination of imaging methods is reported. All devices have been shipped to and degraded at Risø DTU up to 1830 hours in accordance with established ISOS-3 protocols under defined illumination conditions. Imaging of device function at different stages of degradation was performed by laser-beam induced current (LBIC) scanning; luminescence imaging, specifically photoluminescence (PLI) and electroluminescence (ELI); as well as by lock-in thermography (LIT). Each of the imaging techniques exhibits its specific advantages with respect to sensing certain degradation features, which will be compared and discussed here in detail. As a consequence, a combination of several imaging techniques yields very conclusive information about the degradation processes controlling device function. The large variety of device architectures in turn enables valuable progress in the proper interpretation of imaging results - hence revealing the benefits of this large scale cooperation in making a step forward in the understanding of organic solar cell aging and its interpretation by state-of-the-art imaging methods. This journal is © 2012 The Royal Society of Chemistry., RR, MS, MB and HH are grateful for financial support from the Thuringian Ministry of Culture and the German Federal Ministry of Education and Research in the frameworks of FIPV II and PPP (contract number 13N9843), respectively. This work has been supported by the Danish Strategic Research Council (2104-07-0022), EUDP (j.no. 64009-0050) and the Danish National Research Foundation. Partial financial support was also received from the European Commission as part of the Framework 7 ICT 2009 collaborative project HIFLEX (grant no. 248678), partial financial support from the EUIndian framework of the ‘‘Largecells’’ project that received funding from the European Commission’s Seventh Framework Programme (FP7/2007–2013. grant no. 261936), partial financial support was also received from the European Commission as part of the Framework 7 ICT 2009 collaborative project ROTROT (grant no. 288565) and from PVERA-NET (project acronym POLYSTAR). To the Spanish Ministry of Science and Innovation, MICINN-FEDER project ENE2008-04373, to the Consolider NANOSELECT project CSD2007-00041, to the Xarxa de Refer encia en Materials Avanc¸ats per a l’Energia, XaRMAE of the Catalonia Government (Spain). To CONACYT (M exico) for the PhD scholarship awarded to GT-E. DMT acknowledges support from the Inger and Jens Bruun Foundation through The American–Scandinavian Foundation.

Seven distinct sets (n ≥ 12) of state of the art organic photovoltaic devices were prepared by leading research laboratories in a collaboration planned at the Third International Summit on Organic Photovoltaic Stability (ISOS-3). All devices were shipped to RISØ DTU and characterized simultaneously up to 1830 h in accordance with established ISOS-3 protocols under three distinct illumination conditions: accelerated full sun simulation; low level indoor fluorescent lighting; and dark storage with daily measurement under full sun simulation. Three nominally identical devices were used in each experiment both to provide an assessment of the homogeneity of the samples and to distribute samples for a variety of post soaking analytical measurements at six distinct laboratories enabling comparison at various stages in the degradation of the devices. Over 100 devices with more than 300 cells were used in the study. We present here design and fabrication details for the seven device sets, benefits and challenges associated with the unprecedented size of the collaboration, characterization protocols, and results both on individual device stability and uniformity of device sets, in the three illumination conditions. © 2012 The Royal Society of Chemistry., This work has been supported by the Danish Strategic Research Council (2104-07-0022), EUDP (j.no. 64009-0050) and the Danish National Research Foundation. Partial financial support was also received from the European Commission as part of the Framework 7 ICT 2009 collaborative project HIFLEX (grant no. 248678), partial financial support from the EUIndian framework of the ‘‘Largecells’’ project that received funding from the European Commission’s Seventh Framework Programme (FP7/2007–2013. grant no. 261936), partial financial support was also received from the European Commission as part of the Framework 7 ICT 2009 collaborative project ROTROT (grant no. 288565) and from PVERA-NET (project acronym POLYSTAR).

International audience; Conventional lithographic printing processes using porous alumina for offset applications generally use “wet” routes. Recently “dry” processes have been developed which are based on a heat-induced hydrophilic/oleophilic conversion of one or more layers of the coating so that a stronger affinity to-wards ink or water fountain is created at the exposed areas with respect to the surface of the unex-posed coating. Treatments involving rf plasma-enhanced fluorination (PEF) constitute exceptional tools for modifying the surface properties of materials. Many advantages of these techniques can be indeed outlined, when compared to more conventional methods: room-temperature reactions, chemical modi-fications limited to surface only without changing the bulk properties, possible non-equilibrium reac-tions. The influence of PEF treatments on porous alumina layer used in printing plates has been tested with various fluorinated gases (CF4, C3F8 and C4F8) and characterized by XPS. The hydrophobic prop-erties of the fluorinated layer have been deduced from contact angle measurements. Using C4F8 rf-PEF treatment, the outmost surface of the hydrophilic alumina substrate used for lithographic printing is hydrophobized, or in other words, the hydrophilic substrate is converted into a support with hydro-phobic properties. Once being hydrophobized, the surface layer may be rendered hydrophilic using a heat pulse, thus giving rise to switchable hydrophobic-hydrophilic properties of the material.

Zn1-xCuxAl2O4 (0or= xor= 1) compositions have been synthesized by solid-state route, and a color scale going from white (x = 0) to brownish-red (x = 1) with intermediate colors as pale green for x = 0.10 and pale brown for x = 0.30 can be observed. XRD-data refinements on the whole solid solution have allowed defining two critical areas where structural features such as cell parameter and inversion rate as well as cation-oxygen bond distances in 8a and 16d sites of the spinel network exhibit clear unique variations. By observing the direct environment of tetrahedral and octahedral sites potentially occupied by Cu2+ Jahn-Teller cations, the two critical compositions have been estimated to x1 =1/6 and x2 = 4/7. Actually from the x1 and x2 copper contents, the probability of getting Cu2+-Cu2+ pairs involving tetrahedral-octahedral or two octahedral sites respectively is high. Then, the stabilization of Cu2+ JT ions in distorted octahedral site, identified by ESR, is in competition with the occurrence of Cu2+ in tetrahedral sites, and both electronic and steric effects of Cu2+ JT cations lead to the explanation of the evolution of the inversion rate in this series. The study of the optical absorption properties clearly shows that the position and the intensity of the various absorption bands are influenced by the distribution of Cu2+ ions in tetrahedral and octahedral sites, the creation of Cu2+-Cu2+ pairs around the x1 and x2 critical compositions, and the increasing of Cu-O bond covalency. Such an evolution of structural features correlated with electronic properties where various critical compositions have been identified can be generalized to other spinel oxides, considering local distortion around Jahn-Teller ions.

The luminescence of Eu 2+ has been investigated in two families of BaF 2 -rich fluorohalides, Ba 12 Cl 5(1− x ) Br 5 x F 19 ( x ≤0.8) and Ba 7 Cl 2(1− x ) Br 2 x F 12 ( x ≤0.5). In the two kinds of host lattices, under UV excitation Eu 2+ shows an intense blue 5d→4f band emission at 300 K. At low temperature, in addition to the latter, 4f→4f lines are present in the near UV. The efficiency of the photostimulated luminescence (PSL) after X-ray irradiation has been measured and compared with that of BaXF:Eu (X=Cl, Br). High conversion efficiencies have been obtained with compositions Ba 12 Cl 5(1− x ) Br 5 x F 19 for stimulation at 532 nm. The presence of bromine is beneficial. For all compositions a high stimulation energy (SE) is needed to excite Eu 2+ ions through colour centres.