On the mechanical interactions between TiO2 nanoparticles

In this work the mechanical interaction mechanisms between TiO2 nanoparticles at ambient conditions are investigated by using molecular dynamics (MD) and discrete element method (DEM) simulations in comparison to experimental findings. It is shown that the particle interaction forces are crucially determined by the nature of the surface adsorbed water layer of the particles. This dependence controls the characteristic trends of the interparticle forces at the nanoscale with humidity, surface roughness and hydrophilicity. From these insights, comprehensive equations are derived for the calculation of interparticle forces under ambient conditions at the nanoscale. The implementation of these equations into particle contact models enables the fast and accurate simulation of the mechanical behaviour of large nanoparticle assemblies and thus represents a link between the chemical properties of the particle surfaces and the macroscopic mechanical properties of entire nanoparticle films

On the mechanical interactions between TiO2 nanoparticles

In this work the mechanical interaction mechanisms between TiO2 nanoparticles at ambient conditions are investigated by using molecular dynamics (MD) and discrete element method (DEM) simulations in comparison to experimental findings. It is shown that the particle interaction forces are crucially determined by the nature of the surface adsorbed water layer of the particles. This dependence controls the characteristic trends of the interparticle forces at the nanoscale with humidity, surface roughness and hydrophilicity. From these insights, comprehensive equations are derived for the calculation of interparticle forces under ambient conditions at the nanoscale. The implementation of these equations into particle contact models enables the fast and accurate simulation of the mechanical behaviour of large nanoparticle assemblies and thus represents a link between the chemical properties of the particle surfaces and the macroscopic mechanical properties of entire nanoparticle films

Modulation of γ-Secretase Activity by a Carborane-Based Flurbiprofen Analogue

All over the world, societies are facing rapidly aging populations combined with a growing number of patients suffering from Alzheimer’s disease (AD). One focus in pharmaceutical research to address this issue is on the reduction of the longer amyloid-β (Aβ) fragments in the brain by modulation of γ-secretase, a membrane-bound protease. R-Flurbiprofen (tarenflurbil) was studied in this regard but failed to show significant improvement in AD patients in a phase 3 clinical trial. This was mainly attributed to its low ability to cross the blood–brain barrier (BBB). Here, we present the synthesis and in vitro evaluation of a racemic meta-carborane analogue of flurbiprofen. By introducing the carborane moiety, the hydrophobicity could be shifted into a more favourable range for the penetration of the blood–brain barrier, evident by a logD7.4 value of 2.0. Furthermore, our analogue retained γ-secretase modulator activity in comparison to racemic flurbiprofen in a cell-based assay. These findings demonstrate the potential of carboranes as phenyl mimetics also in AD research

An Architectural Blueprint For Digital Energy Platforms In Industrial Energy Flexibility Applications

This paper examines the integration of industrial demand-side management into existing digital energy platforms, considering the global push towards renewable energy sources and climate change mitigation. Despite the proliferation of digital energy platforms, there is a notable lack of energy flexibility measures within these systems, which are essential for industrial demand-side management. Through a comprehensive analysis, this paper presents an Architectural Blueprint designed to enable platform providers to assess and integrate essential functionalities for energy flexibility. The research follows a systematic approach, starting with an outline of the necessary architectural components and their relevance. Subsequently, a gap analysis is conducted to pinpoint the discrepancies between the existing functionalities of digital energy platforms and the capabilities necessary for the efficient integration of energy flexibility. The study concludes with strategic recommendations for enhancing platform capabilities. The paper contributes a new and meaningful architecture blueprint to digital energy platforms by enabling platform providers to align their systems with the needs of energy-flexible manufacturing

Carboranyl Derivatives of Rofecoxib with Cytostatic Activity against Human Melanoma and Colon Cancer Cells.

Owing to the involvement of cyclooxygenase-2 (COX-2) in carcinogenesis, COX-2-selective inhibitors are increasingly studied for their potential cytotoxic properties. Moreover, the incorporation of carboranes in structures of established anti-inflammatory drugs can improve the potency and metabolic stability of the inhibitors. Herein, we report the synthesis of carborane-containing derivatives of rofecoxib that display remarkable cytotoxic or cytostatic activity in the micromolar range with excellent selectivity for melanoma and colon cancer cell lines over normal cells. Furthermore, it was shown that the carborane-modified derivatives of rofecoxib showed different modes of action that were dependent on the cell type

An in-flight plasma diagnostic package for spacecraft with electric propulsion

The plasma diagnostics presented in this article target the plasma surrounding a spacecraft that is created by the electric thruster and its surface modifying effects. The diagnostic package includes a retarding potential analyzer, a plane Langmuir probe, and an erosion sensor. The paper describes the instrument as well as suitable test environments for mimicking the effects expected in space and shows test results. The system is to fly for the first time on the Heinrich Hertz satellite, which is scheduled to be launched in 2023. The spacecraft will be equipped with a pair of Highly Efficient Multistage Plasma Thrusters (HEMPT) and a pair of Hall thrusters for redundancy

Evaluation of stratospheric age of air from CF4_{4}, C2_{2}F6_{6}, C3_{3}F8_{8}, CHF3_{3}, HFC-125, HFC-227ea and SF6_{6}; Implications for the calculations of halocarbon lifetimes, fractional release factors and ozone depletion potentials

In a changing climate, potential stratospheric circulation changes require long-term monitoring. Stratospheric trace gas measurements are often used as a proxy for stratospheric circulation changes via the “mean age of air” values derived from them. In this study, we investigated five potential age of air tracers – the perfluorocarbons CF4, C2F6 and C3F8 and the hydrofluorocarbons CHF3 (HFC-23) and HFC-125 – and compare them to the traditional tracer SF6 and a (relatively) shorter-lived species, HFC-227ea. A detailed uncertainty analysis was performed on mean ages derived from these “new” tracers to allow us to confidently compare their efficacy as age tracers to the existing tracer, SF6. Our results showed that uncertainties associated with the mean age derived from these new age tracers are similar to those derived from SF6, suggesting that these alternative compounds are suitable in this respect for use as age tracers. Independent verification of the suitability of these age tracers is provided by a comparison between samples analysed at the University of East Anglia and the Scripps Institution of Oceanography. All five tracers give younger mean ages than SF6, a discrepancy that increases with increasing mean age. Our findings qualitatively support recent work that suggests that the stratospheric lifetime of SF6 is significantly less than the previous estimate of 3200 years. The impact of these younger mean ages on three policy-relevant parameters – stratospheric lifetimes, fractional release factors (FRFs) and ozone depletion potentials – is investigated in combination with a recently improved methodology to calculate FRFs. Updates to previous estimations for these parameters are provided

Evaluation of stratospheric age of air from CF4, C2F6, C3F8, CHF3, HFC-125, HFC-227ea and SF6; implications for the calculations of halocarbon lifetimes, fractional release factors and ozone depletion potentials

In a changing climate, potential stratospheric circulation changes require long-term monitoring. Stratospheric trace gas measurements are often used as a proxy for stratospheric circulation changes via the <q>mean age of air</q> values derived from them. In this study, we investigated five potential age of air tracers – the perfluorocarbons CF₄, C₂F₆ and C₃F₈ and the hydrofluorocarbons CHF₃ (HFC-23) and HFC-125 – and compare them to the traditional tracer SF₆ and a (relatively) shorter-lived species, HFC-227ea. A detailed uncertainty analysis was performed on mean ages derived from these <q>new</q> tracers to allow us to confidently compare their efficacy as age tracers to the existing tracer, SF₆. Our results showed that uncertainties associated with the mean age derived from these new age tracers are similar to those derived from SF₆, suggesting that these alternative compounds are suitable in this respect for use as age tracers. Independent verification of the suitability of these age tracers is provided by a comparison between samples analysed at the University of East Anglia and the Scripps Institution of Oceanography. All five tracers give younger mean ages than SF₆, a discrepancy that increases with increasing mean age. Our findings qualitatively support recent work that suggests that the stratospheric lifetime of SF₆ is significantly less than the previous estimate of 3200 years. The impact of these younger mean ages on three policy-relevant parameters – stratospheric lifetimes, fractional release factors (FRFs) and ozone depletion potentials – is investigated in combination with a recently improved methodology to calculate FRFs. Updates to previous estimations for these parameters are provided