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    Dissemination of PV-Battery systems in the German residential sector up to 2050: Technological diffusion from multidisciplinary perspectives

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    A decarbonization of the European energy system implies great changes in the residential sector. Recently, the sector does not show the necessary dynamics. Apparently decarbonizing the sector requires a new momentum. Using PV-Battery systems as key technology for the residential sector for becoming more environmentally sustainable as an example, we take a closer look at the complexity of technology diffusions in the residential sector. By employing a socio-techno-economic (SoTeEc) framework approach we consider that diffusion processes are impacted by a broad range of measurable and non-measurable factors. Our framework combines a techno-economic with a socio-economic analysis. With the techno-economic analysis we assess the drivers of technology diffusion of PV-Battery systems in private households whereas the socio-economic analysis focuses on the role of a) the household sector in the overall social-economic system and b) actor specific factors like attitudes. The link of the two approaches enables us to identify which techno-economic scenarios are feasible from socio-economic point of view and vice versa. Hence, we can identify scenarios which fulfill simultaneously requirements from techno-economic and socio-economic point of views. Such scenarios can serve as a starting point for policy recommendations

    Zinc loading in urea-formaldehyde nanocomposites increases nitrogen and zinc micronutrient fertilization efficiencies in poor sand substrate

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    Agricultural output needs significant increases to feed the growing population. Fertilizers are essential for plant production systems, with nitrogen (N) being the most limiting nutrient for plant growth. It is commonly supplied to crops as urea. Still, due to volatilization, up to 50 % of the total N application is lost. Slow or controlled release fertilizers are being developed to reduce these losses. The co-application of zinc (Zn) as a micronutrient can increase N absorption. Thus, we hypothesize that the controlled delivery of both nutrients (N and Zn) in an integrated system can improve uptake efficiency. Here we demonstrate an optimized fertilizer nanocomposite based on urea:urea-formaldehyde matrix loaded with ZnSO4 or ZnO. This nanocomposite effectively stimulates maize development, with consequent adequate N uptake, in an extreme condition – a very nutrient-poor sand substrate. Our results indicate that the Zn co-application is beneficial for plant development. However, there were advantages for ZnO due to its high Zn content. We discuss that the dispersion favors the Zn delivery as the nanoparticulated oxide in the matrix. Concerning maize development, we found that root morphology is altered in the presence of the fertilizer nanocomposite. Increased root length and surface area may improve soil nutrient uptake, potentially accompanied by increased root exudation of essential compounds for N release from the composite structure

    Resolving ambiguities in core size determination of magnetic nanoparticles from magnetic frequency mixing data

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    Frequency mixing magnetic detection (FMMD) has been widely utilized as a measurement technique in magnetic immunoassays. It can also be used for the characterization and distinction (also known as “colourization”) of different types of magnetic nanoparticles (MNPs) based on their core sizes. In a previous work, it was shown that the large particles contribute most of the FMMD signal. This leads to ambiguities in core size determination from fitting since the contribution of the small-sized particles is almost undetectable among the strong responses from the large ones. In this work, we report on how this ambiguity can be overcome by modelling the signal intensity using the Langevin model in thermodynamic equilibrium including a lognormal core size distribution fL(dc,d0,σ) fitted to experimentally measured FMMD data of immobilized MNPs. For each given median diameter d0, an ambiguous amount of best-fitting pairs of parameters distribution width σ and number of particles Np with R² > 0.99 are extracted. By determining the samples’ total iron mass, mFe, with inductively coupled plasma optical emission spectrometry (ICP-OES), we are then able to identify the one specific best-fitting pair (σ, Np) one uniquely. With this additional externally measured parameter, we resolved the ambiguity in core size distribution and determined the parameters (d0, σ, Np) directly from FMMD measurements, allowing precise MNPs sample characterization

    Interface-Assisted Room-Temperature Magnetoresistance in Cu-Phenalenyl-Based Magnetic Tunnel Junctions

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    Delocalized carbon-based radical species with unpaired spin, such as the phenalenyl (PLY) radical, have opened avenues for developing multifunctional organic spintronic devices. Using direct laser writing and in situ deposition, we successfully fabricated Cu-PLY- and Zn-PLY-based organic magnetic tunnel junctions (OMTJs) with improved morphology and a reduced junction area of 3 × 8 μm2. The nonlinear and weakly temperature-dependent current–voltage (I–V) characteristics in combination with the low organic barrier height suggest tunneling as the dominant transport mechanism in the structurally and dimensionally optimized OMTJs. Cu-PLY-based OMTJs show significant magnetoresistance up to 14% at room temperature due to the formation of hybrid states at the metal–molecule interfaces called “spinterface”, which reveals the importance of spin-dependent interfacial modification in OMTJs’ design. Additionally, at high bias, in the absence of a magnetic field, OMTJ shows stable voltage-driven resistive switching. Cu-PLY having spin 1/2 with net magnetic moment demonstrates magnetic hardening between the surface molecule at the Co interface and gives rise to stable MR, which suggests its use as a feasible and scalable platform for building molecular-scale quantum memristors and processors

    Direct Visualization of Distorted Twin Boundaries in Ce-Doped GdFeO3

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    Utilizing advanced transmission electron microscopy (TEM), the structure at the (110)-type twin boundary (TB) of Ce-doped GdFeO3 (C-GFO) has been investigated with picometer precision. Such a TB is promising to generate local ferroelectricity within a paraelectric system, while precise knowledge about its structure is still largely missing. In this work, a direct measurement of the cation off-centering with respect to the neighboring oxygen is enabled by integrated differential phase contrast (iDPC) imaging, and up to 30 pm Gd off-centering is highly localized at the TB. Further electron energy loss spectroscopy (EELS) analysis demonstrates a slight accumulation of oxygen vacancies at the TB, a self-balanced behavior of Ce at the Gd sites, and a mixed occupation of Fe2+ and Fe3+ at the Fe sites. Our results provide an informative picture with atomic details at the TB of C-GFO, which is indispensable to further push the potential of grain boundary engineering

    Breakdown of Archard law due to transition of wear mechanism from plasticity to fracture

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    Widely used to quantify material wear, the Archard wear law was derived from the asperity flattening model. However, the flattening model is so idealized that it cannot properly represent the real situation with general interlocked asperities, where asperity plowing dominates the wear instead of shearing flattened asperity. Using molecular dynamics simulations, we discussed if Archard law can hold during plowing wear of interlocked interface. Our results indicated Archard law breaks down when fracture dominates the wear. Furthermore, increasing interfacial adhesion or decreasing material ductility changes the dominant wear factor from plasticity to fracture. Finally, we proposed a criterion to determine when Archard wear law will break down and discussed the proposed criterion for real materials

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