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[en] Ethical and societal issues concerning justice, safety, risks, and benefits are well-established topics in the discourses of nanotechnology innovation and development. That nanotechnology innovation should be socially and ethically responsible is generally accepted by scientists, policymakers, regulators, and industry, and the idea of public involvement and communication is part and parcel of the conceptualization of responsible technology development. This paper systematically reviews the social science research literature accumulated between 2002 and 2018 on the communication of nanotechnology. A critical and constructivist perspective on policy problems guides the analysis. Two questions are asked of this literature: what problems are identified regarding the communication of nanotechnology to the public? How can these problems be managed and/or resolved? Three different problem themes are identified: the public, societal institutions, and nanotechnology itself. While for some identified problems, there are corresponding solutions; in other instances, there is little alignment between problems and solutions. In conclusion, the paper recommends that in communicating nanotechnology to the public: (i) the objectives of communication should be defined; (ii) previous research should be used responsibly; (iii) communication strategies should be adapted to the context; and (iv) effort should not be spent trying to develop a generic framework for communication.
[en] Due to technical constraints this article was published in volume 240:1 with erroneous article citation ID number 1 whereas this should have been 71 which is corrected as such. Springer Nature sincerely apologizes towards the author(s) for the inconvenience caused.
[en] Highlights: • The present smart pipet tip enables in situ evaluation of solution characteristics. • Firstly, the electrical charges inside the pipet tip is advantageously utilized. • Multi-parametric effect on liquid-solid triboelectricity is effectively separated. • The morphology of nanoparticles can be in situ predicted by using the smart pipet tip. Pipet tips are commonly utilized laboratory tools to transfer adjustable volume of liquid in various fields of chemistry, biology and physics. Recently, we have reported that the ordinary pipetting procedure always involves spontaneous liquid-solid contact electrification, resulting in generation of net electrical charges on the dispensed solution and the inner surface of the polymeric pipet tip. In this study, a concept of a smart pipet tip is proposed to evaluate the electrolyte concentration of the dispensed solution by use of spontaneously generated electric signals during the ordinary pipetting procedure. The smart pipet tip possessing triboelectricity and thermoelectricity detecting modules is advantageous as it performs in situ evaluation of solution characteristics without any subsidiary solution handling process. The spontaneously generated electric signals are intensively investigated with the theoretical analyses. The proof-of-concept demonstration of the present smart pipet tip is shown for in situ prediction of morphology of nanoparticles during their synthetic reaction, which critically determines their catalytic activity.
[en] Highlights: • Simulation of solar prosumers diffusion and cost recovery of distribution grids. • Quantification of the distribution effect and deviations from the cost causation principle. • Scenarios for: Net purchase and sale, net metering, flat tariff, capacity tariff. • Recommendations for energy policy design. - Abstract: Solar prosumers are about to revolutionize the power sector. Utilities are challenged in recovering the costs of distribution grids, as parts of their revenue basis decreases through self-consumption. Adjusting the grid tariff sets off a reinforcing feedback loop that increases the attractiveness of solar investments, but also leads to a distribution effect between solar prosumers and conventional consumers. The question is: How to recover distribution grid costs equitable without hampering the diffusion of solar power? Can the two criteria be fulfilled at the same time, or is do we aim for squaring a circle? To address this question, I present a System Dynamics simulation model designed to understand the interactions and assess these competing goals. The occurring distribution effect under the volumetric grid tariff with net purchase and sale appears to be rather limited. Simulation experiments reveal that grid tariff designs strongly influence investments for solar power. A capacity tariff can reduce deviations from the cost causation principle of solar prosumers and incentivizes investments in decentralized storage solutions to reduce peak demand. Nevertheless, also the capacity tariff causes a distribution effect.
[en] Highlights: • A monomeric form of hypericin in DSCG aqueous solution was confirmed. • pK constants at neutral and alkaline pH for hypericin were determined. • Three individual dissociations steps of hypericin were observed. In this work we established three from altogether six proton dissociation constants (pKa) of hydroxyl groups of hypericin in its monomeric form. The monomeric state of hypericin (5.0 × 10−6 mol·L−1) in aqueous solution was stabilised by the presence of hydrotropic drug Cromolyn disodium salt (6.0 × 10−2 mol·L−1). Data show that one acid-base transition occurs with the pKa of 7.8 and the other two are characterised by the apparent single pKa of 11.5. The spectral changes of hypericin above pH 13 indicate that the last two hydroxyls are deporotonized at this high pH values.
[en] Statistical processing of the data for multicomponent aqueous systems with a molecular character of the solutions confirms the planarity of the compositions of saturated solutions, expressed in wt % on the lines of monovariant equilibria and in nonvariant points for systems with all types of solutions (ionic, ionic–molecular, and molecular), proving the colligative property of solutions saturated by two or more solid phases.
[en] Superconducting technology applications in electric machines have long been pursued due to their significant advantages of higher efficiency and power density over conventional technology. However, in spite of many successful technology demonstrations, commercial adoption has been slow, presumably because the threshold for value versus cost and technology risk has not yet been crossed. One likely path for disruptive superconducting technology in commercial products could be in applications where its advantages become key enablers for systems which are not practical with conventional technology. To help systems engineers assess the viability of such future solutions, we present a technology roadmap for superconducting machines. The timeline considered was ten years to attain a Technology Readiness Level of 6+, with systems demonstrated in a relevant environment. Future projections, by definition, are based on the judgment of specialists, and can be subjective. Attempts have been made to obtain input from a broad set of organizations for an inclusive opinion. This document was generated through a series of teleconferences and in-person meetings, including meetings at the 2015 IEEE PES General meeting in Denver, CO, the 2015 ECCE in Montreal, Canada, and a final workshop in April 2016 at the University of Illinois, Urbana-Champaign that brought together a broad group of technical experts spanning the industry, government and academia. (topical review)
[en] The effect of solution treatment on compression mechanical and corrosion resistance properties of Mg–6Zn–0.5Nd–xCa alloys has been investigated in the current study. The results show that with solution treatment, the corrosion rate of Mg–6Zn–0.5Nd–xCa alloy was reduced to 1.51 mm yr−1. The corrosion mechanism of Mg–6Zn–0.5Nd–xCa alloys tend to be uniform corrosion because of the secondary phase particle is diffused into matrix. The fracture strength of Mg–6Zn–0.5Nd–0.3Ca alloy has been dramatically increased by about 68%. With Ca content increasing, grains are refined and the compression mechanical properties of cast alloys are gradually increased to some extent. The Mg–6Zn–0.5Nd–0.5Ca alloy shows great corrosion resistance than other studied alloys. (paper)
[en] This study focused on the adsorption characteristics of jackfruit seed as an adsorbent for the removal of malachite green (MG) dye from aqueous solution via batch adsorption experiment. The performance of the adsorbent was investigated through several parameters, namely contact time, pH, dye concentration, ionic strength and temperature. Adsorption of MG by jackfruit seed required 2 h to reach equilibrium and was found to be sensitive to the pH medium, but relatively unaffected by ionic strength. The Langmuir, Freundlich and Sips isotherm models were used to describe the adsorption process, while the Lagergren first-order, pseudo-second-order and Weber–Morris intraparticle diffusion models were used to predict the adsorption mechanism. The Freundlich model was found to best fit the experimental data, and the maximum monolayer capacity (from Langmuir model) was determined as 66 mg g−1. The kinetics mechanism followed pseudo-second-order model and intraparticle diffusion was found not to be the rate-determining step. In addition, machine learning models such as artificial neural network and random forest were used as predictive models for the adsorption process where high R values of 0.966 and 0.981, respectively, and low RMSE of 0.048 and 0.038 were obtained. This study concludes that jackfruit seed has the potential to be used as a low-cost adsorbent for the removal of toxic MG dye.
[en] The charge and potential distributions in an electric double layer result from various chemical and physical interactions between an interface and the adjacent electrolyte solution. The charge typically originates from a chemical equilibrium between the reactive surface and certain potential determining ions in the solution (i.e., surface charge regulation). This surface chemistry however, is strongly dependent on the wide variety of interactions between all species in the solution, as well as with the interface. These interactions could be Coulombic and non-Coulombic, and are system-specific. The focus of this study is on the ion valency and its effect on the Coulombic interactions, their interplay with the molecular excluded volume, and attraction in the fluid phase, as well as with the electric double layer interface. (paper)