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- ItemElectrical and magnetic properties of NiTiO3 nanoparticles synthesized by the sol-gel synthesis method and microwave sintering(Amsterdam : Elsevier B.V., 2019) Pavithra, C.; Madhuri, W.In this paper, we focused on microwave sintered NiTiO3 nanoparticles synthesized via sol-gel method. The crystal structure was determined by the X-ray diffraction. Vibrational bands related to Ni-O and Ti-O bands were confirmed using the Fourier transform infrared spectrum. These NiTiO3 ceramics obeyed semiconductor behavior of Arrhenius type. The activation energy was found to be 0.04 μeV. The M-H curve exhibited superparamagnetic behavior at room temperature.
- ItemMicrostructure and elastic deformation behavior of β-type Ti-29Nb-13Ta-4.6Zr with promising mechanical properties for stent applications(Amsterdam : Elsevier B.V., 2019) Plaine, A.H.; Silva, M.R.D.; Bolfarini, C.In this paper, an attempt was made to combine theoretical composition design and thermo-mechanical treatments to produce a metastable β-type titanium alloy with mechanical compatibility for self-expandable stent applications. Metastable β-type Ti-29Nb-13Ta-4.6â»Zr (wt.%) thin-wires with an elastic modulus of 46â»GPa and a yield strength of 920â»MPa were successfully fabricated by cold rolling and low temperature aging. This combination of high yield strength and comparatively low elastic modulus resulted in enhanced elastic recoverable strain of 1.9%, which is much higher than that of the conventional metallic stent materials. The microstructure responsible for the much sought-after mechanical properties was observed to be mainly consisted of a homogeneous distribution of nanometer-sized α-precipitates in a β-phase matrix obtained via a spinodal decomposition of the pre-existed α″-martensite phase through α″â»→â»α″ leanâ»+â»α″ richâ»→â»αâ»+â»β. The α-precipitates increase the strength of the material by hindering the motion of dislocations (spinodal hardening) while the β-matrix with relatively low content of β-stabilizers gives rise to the observed low elastic modulus. More broadly, these findings could be extended to developing advanced metastable β-type titanium alloys for implant and other engineering applications.
- ItemHydrological impacts of moderate and high-end climate change across European river basins(Amsterdam : Elsevier B.V., 2018) Lobanova, A.; Liersch, S.; Nunes, J.P.; Didovets, I.; Stagl, J.; Huang, S.; Koch, H.; Rivas López, M.D.R.; Maule, C.F.; Hattermann, F.; Krysanova, V.Study region: To provide a picture of hydrological impact of climate change across different climatic zones in Europe, this study considers eight river basins: Tagus in Iberian Peninsula; Emån and Lule in Scandinavia; Rhine, Danube and Teteriv in Central and Eastern Europe; Tay on the island of Great Britain and Northern Dvina in North-Eastern Europe. Study focus: In this study the assessment of the impacts of moderate and high-end climate change scenarios on the hydrological patterns in European basins was conducted. To assess the projected changes, the process-based eco-hydrological model SWIM (Soil and Water Integrated Model) was set up, calibrated and validated for the basins. The SWIM was driven by the bias-corrected climate projections obtained from the coupled simulations of the Global Circulation Models and Regional Climate Models. New hydrological insights for the region: The results show robust decreasing trends in water availability in the most southern river basin (Tagus), an overall increase in discharge in the most northern river basin (Lule), increase in the winter discharge and shift in seasonality in Northern and Central European catchments. The impacts of the high-end climate change scenario RCP 8.5 continue to develop until the end of the century, while those of the moderate climate change scenario RCP 4.5 level-off after the mid-century. The results of this study also confirm trends, found previously with mostly global scale models.
- ItemNickel-Catalyzed Carbonylative Synthesis of Functionalized Alkyl Iodides(Amsterdam : Elsevier B.V., 2018) Peng, J.-B.; Wu, F.-P.; Xu, C.; Qi, X.; Ying, J.; Wu, X.-F.Chemistry; Catalysis; Organic Synthesis © 2018 The Author(s)Functionalized alkyl iodides are important compounds in organic chemistry and biology. In this communication, we developed an interesting nickel-catalyzed carbonylative synthesis of functionalized alkyl iodides from aryl iodides and ethers. With Mo(CO)6 as the solid CO source, both cyclic and acyclic ethers were activated, which is also a challenging topic in organic synthesis. Functionalized alkyl iodides were prepared in moderate to excellent yields with outstanding functional group tolerance. Besides the high value of the obtained products, all the atoms from the starting materials were incorporated in the final products and the reaction had high atom efficiency as well.
- ItemPresentation of uncertainties on web platforms for climate change information(Amsterdam : Elsevier B.V., 2011) Reusser, D.E.; Wrobel, M.; Nocke, T.; Sterzel, T.; Förster, H.; Kropp, J.P.Adaptation to climate change is gaining attention and is very challenging because it requires action at a local scale in response to global problems. At the same time, spatial and temporal uncertainty about climate impacts and effects of adaptation projects is large. Data on climate impacts and adaptation is collected and presented in web-based platforms such as ci:grasp, which is unique in its structuredness and by explicitly linking adaptation projects to the addressed climate impacts. The challenge to find an adequate and readable representation of uncertainty in this context is large and research is just in the initial phase to provide solutions to the problem. Our goal is to present the structure required to address spatial and temporal uncertainty within ci:grasp. We compare existing concepts and representations for uncertainty communication with current practices on web-based platforms. From our review we derive an uncertainty framework for climate information going beyond what is currently present in the web. We make use of a multi-step approach in communicating the uncertainty and a typology of uncertainty distinguishing between epistemic, natural stochastic, and human reflexive uncertainty. While our suggestions are a step forward, much remains to be done.
- ItemTowards Oxide Electronics: a Roadmap(Amsterdam : Elsevier B.V., 2019) Coll, M.; Fontcuberta, J.; Althammer, M.; Bibes, M.; Boschker, H.; Calleja, A.; Cheng, G.; Cuoco, M.; Dittmann, R.; Dkhil, B.; El Baggari, I.; Fanciulli, M.; Fina, I.; Fortunato, E.; Frontera, C.; Fujita, S.; Garcia, V.; Goennenwein, S.T.B.; Granqvist, C.-G.; Grollier, J.; Gross, R.; Hagfeldt, A.; Herranz, G.; Hono, K.; Houwman, E.; Huijben, M.; Kalaboukhov, A.; Keeble, D.J.; Koster, G.; Kourkoutis, L.F.; Levy, J.; Lira-Cantu, M.; MacManus-Driscoll, J.L.; Mannhart, J.; Martins, R.; Menzel, S.; Mikolajick, T.; Napari, M.; Nguyen, M.D.; Niklasson, G.; Paillard, C.; Panigrahi, S.; Rijnders, G.; Sánchez, F.; Sanchis, P.; Sanna, S.; Schlom, D.G.; Schroeder, U.; Shen, K.M.; Siemon, A.; Spreitzer, M.; Sukegawa, H.; Tamayo, R.; van den Brink, J.; Pryds, N.; Granozio, F.M.[No abstract available]
- ItemScreening of microbial communities associated with endive lettuce during postharvest processing on industrial scale(Amsterdam : Elsevier B.V., 2018) Fröhling, A.; Rademacher, A.; Rumpold, B.; Klocke, M.; Schlüter, O.In this study, the composition of the microbial community on endive lettuce (Cichorium endivia) was evaluated during different postharvest processing steps. Microbial community structure was characterized by culture-dependent and culture-independent methods. Endive lettuce was sampled exemplarily at four different stages of processing (raw material, cut endive lettuce, washed endive lettuce, and spin-dried (ready to pack) endive lettuce) and analysed by plate count analysis using non-selective and selective agar plates with subsequent identification of bacteria colonies by matrix-assisted laser desorption/ionization time-of light mass spectrometry (MALDI-TOF MS). Additionally, terminal-restriction fragment length polymorphism (TRFLP) analysis and 16S rRNA gene nucleotide sequence analysis were conducted. The results revealed structural differences in the lettuce microbiomes during the different processing steps. The most predominant bacteria on endive lettuce were detected by almost all methods. Bacterial species belonging to the families Pseudomonadaceae, Enterobacteriaceae, Xanthomonadaceae, and Moraxellaceae were detected in most of the examined samples including some unexpected potentially human pathogenic bacteria, especially those with the potential to build resistance to antibiotics (e.g., Stenotrophomonas maltophilia (0.9 % in cut sample, 0.4 % in spin-dried sample), Acinetobacter sp. (0.6 % in raw material, 0.9 % in cut sample, 0.9 % in washed sample, 0.4 % in spin-dried sample), Morganella morganii (0.2 % in cut sample, 3 % in washed sample)) revealing the potential health risk for consumers. However, more seldom occurring bacterial species were detected in varying range by the different methods. In conclusion, the applied methods allow the determination of the microbiome's structure and its dynamic changes during postharvest processing in detail. Such a combined approach enables the implementation of tailored control strategies including hygienic design, innovative decontamination techniques, and appropriate storage conditions for improved product safety.
- ItemNatural variability or anthropogenically-induced variation? Insights from 15 years of multidisciplinary observations at the arctic marine LTER site HAUSGARTEN(Amsterdam : Elsevier B.V., 2016) Soltwedel, T.; Bauerfeind, E.; Bergmann, M.; Bracher, A.; Budaeva, N.; Busch, K.; Cherkasheva, A.; Fahl, K.; Grzelak, K.; Hasemann, C.; Jacob, M.; Kraft, A.; Lalande, C.; Metfies, K.; Nöthig, E.-M.; Meyer, K.; Quéric, N.-V.; Schewe, I.; Włodarska-Kowalczuk, M.; Klages, M.Time-series studies of arctic marine ecosystems are rare. This is not surprising since polar regions are largely only accessible by means of expensive modern infrastructure and instrumentation. In 1999, the Alfred Wegener Institute, Helmholtz-Centre for Polar and Marine Research (AWI) established the LTER (Long-Term Ecological Research) observatory HAUSGARTEN crossing the Fram Strait at about 79°N. Multidisciplinary investigations covering all parts of the open-ocean ecosystem are carried out at a total of 21 permanent sampling sites in water depths ranging between 250 and 5500 m. From the outset, repeated sampling in the water column and at the deep seafloor during regular expeditions in summer months was complemented by continuous year-round sampling and sensing using autonomous instruments in anchored devices (i.e., moorings and free-falling systems). The central HAUSGARTEN station at 2500 m water depth in the eastern Fram Strait serves as an experimental area for unique biological in situ experiments at the seafloor, simulating various scenarios in changing environmental settings. Long-term ecological research at the HAUSGARTEN observatory revealed a number of interesting temporal trends in numerous biological variables from the pelagic system to the deep seafloor. Contrary to common intuition, the entire ecosystem responded exceptionally fast to environmental changes in the upper water column. Major variations were associated with a Warm-Water-Anomaly evident in surface waters in eastern parts of the Fram Strait between 2005 and 2008. However, even after 15 years of intense time-series work at HAUSGARTEN, we cannot yet predict with complete certainty whether these trends indicate lasting alterations due to anthropologically-induced global environmental changes of the system, or whether they reflect natural variability on multiyear time-scales, for example, in relation to decadal oscillatory atmospheric processes.
- ItemWeb-based access, aggregation, and visualization of future climate projections with emphasis on agricultural assessments(Amsterdam : Elsevier B.V., 2018) Villoria, N.B.; Elliott, J.; Müller, C.; Shin, J.; Zhao, L.; Song, C.Access to climate and spatial datasets by non-specialists is restricted by technical barriers involving hardware, software and data formats. We discuss an open-source online tool that facilitates downloading the climate data from the global circulation models used by the Inter-Sectoral Impacts Model Intercomparison Project. The tool also offers temporal and spatial aggregation capabilities for incorporating future climate scenarios in applications where spatial aggregation is important. We hope that streamlined access to these data facilitates analysis of climate related issues while considering the uncertainties derived from future climate projections and temporal aggregation choices.
- ItemProjections of temperature-related excess mortality under climate change scenarios(Amsterdam : Elsevier B.V., 2017) Gasparrini, A.; Guo, Y.; Sera, F.; Vicedo-Cabrera, A.M.; Huber, V.; Tong, S.; de Sousa Zanotti Stagliorio Coelho, M.; Nascimento Saldiva, P.H.; Lavigne, E.; Matus Correa, P.; Valdes Ortega, N.; Kan, H.; Osorio, S.; Kyselý, J.; Urban, A.; Jaakkola, J.J.K.; Ryti, N.R.I.; Pascal, M.; Goodman, P.G.; Zeka, A.; Michelozzi, P.; Scortichini, M.; Hashizume, M.; Honda, Y.; Hurtado-Diaz, M.; Cesar Cruz, J.; Seposo, X.; Kim, H.; Tobias, A.; Iñiguez, C.; Forsberg, B.; Åström, D.O.; Ragettli, M.S.; Guo, Y.L.; Wu, C.-F.; Zanobetti, A.; Schwartz, J.; Bell, M.L.; Dang, T.N.; Van, D.D.; Heaviside, C.; Vardoulakis, S.; Hajat, S.; Haines, A.; Armstrong, B.Background: Climate change can directly affect human health by varying exposure to non-optimal outdoor temperature. However, evidence on this direct impact at a global scale is limited, mainly due to issues in modelling and projecting complex and highly heterogeneous epidemiological relationships across different populations and climates. Methods: We collected observed daily time series of mean temperature and mortality counts for all causes or non-external causes only, in periods ranging from Jan 1, 1984, to Dec 31, 2015, from various locations across the globe through the Multi-Country Multi-City Collaborative Research Network. We estimated temperature–mortality relationships through a two-stage time series design. We generated current and future daily mean temperature series under four scenarios of climate change, determined by varying trajectories of greenhouse gas emissions, using five general circulation models. We projected excess mortality for cold and heat and their net change in 1990–2099 under each scenario of climate change, assuming no adaptation or population changes. Findings: Our dataset comprised 451 locations in 23 countries across nine regions of the world, including 85 879 895 deaths. Results indicate, on average, a net increase in temperature-related excess mortality under high-emission scenarios, although with important geographical differences. In temperate areas such as northern Europe, east Asia, and Australia, the less intense warming and large decrease in cold-related excess would induce a null or marginally negative net effect, with the net change in 2090–99 compared with 2010–19 ranging from −1·2% (empirical 95% CI −3·6 to 1·4) in Australia to −0·1% (−2·1 to 1·6) in east Asia under the highest emission scenario, although the decreasing trends would reverse during the course of the century. Conversely, warmer regions, such as the central and southern parts of America or Europe, and especially southeast Asia, would experience a sharp surge in heat-related impacts and extremely large net increases, with the net change at the end of the century ranging from 3·0% (−3·0 to 9·3) in Central America to 12·7% (−4·7 to 28·1) in southeast Asia under the highest emission scenario. Most of the health effects directly due to temperature increase could be avoided under scenarios involving mitigation strategies to limit emissions and further warming of the planet. Interpretation: This study shows the negative health impacts of climate change that, under high-emission scenarios, would disproportionately affect warmer and poorer regions of the world. Comparison with lower emission scenarios emphasises the importance of mitigation policies for limiting global warming and reducing the associated health risks. Funding: UK Medical Research Council.