Metallocene/carbon hybrids prepared by a solution process for supercapacitor applications

Efficient and scalable solution-based processes are not generally available to integrate well-studied pseudocapacitive materials (i.e., metal oxides and conducting polymers) with other components such as porous carbon, mainly because these classes of pseudocapacitive systems have poor solubilities in solvents and exhibit no specific interactions with the other component. Here we report, for the first time, the integration of a metallocene polymer, polyvinylferrocene (PVF), with carbon nanotubes (CNTs) via a simple solution process for supercapacitor applications. The solution processability of the PVF/CNT hybrid is due to the high solubilities of PVF in organic solvents and the unique ability of the metallocene/carbon system to form stable dispersions through the π–π stacking interactions between the two components. The nanostructure and electrochemical properties of the hybrid can be manipulated systematically by adjusting the composition of the dispersion. The hybrid with the optimized composition exhibits unusually high capacitance (1452 F g[superscript −1]) and energy density (79.5 W h kg[superscript −1]) obtained in a standard two-electrode configuration, outperforming previously reported pseudocapacitive materials.United States. Dept. of EnergyMIT Energy Initiative (Seed Fund Grant

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

Correction to: Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

The original version of this article unfortunately contained a mistake

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

Interfacial Engineering of a Carbon Nitride-Graphene Oxide-Molecular Ni Catalyst Hybrid for Enhanced Photocatalytic Activity

Abstract can be found here: https://doi.org/10.1021/acscatal.8b0196

Optimal Driving Profiles in Railway Systems based on Data Envelopment Analysis

The present study focuses on the development of a dynamically re-configurable Information Communication Technology (ICT) infrastructure to support the sustainable development of railway network. Once data have been collected, the extracted knowledge is used to develop a set of applications that can improve the energy efficient operation of railway systems. A typical example includes the identification of the optimal driving profiles in terms of energy consumption. In the present study, this is achieved through the adoption of an optimization framework based on Data Envelopment Analysis (DEA). The performance of the proposed scheme is evaluated based on actual data collected at an operation tramway system. Preliminary results illustrate that when the proposed method is applied, a 10% reduction in the overall power consumption can be achieved

FexNi9-xS8 (x = 3-6) as potential photocatalysts for solar-driven hydrogen production?

The efficient reduction of protons by non-noble metals under mild conditions is a challenge for our modern society. Nature utilises hydrogenases, enzymatic machineries that comprise iron- and nickel- containing active sites, to perform the conversion of protons to hydrogen. We herein report a straightforward synthetic pathway towards well-defined particles of the bio-inspired material FexNi9-xS8, a structural and functional analogue of hydrogenase metal sulfur clusters. Moreover, the potential of pentlandites to serve as photocatalysts for solar-driven H2-production is assessed for the first time. The FexNi9-xS8 materials are visible light responsive (band gaps between 2.02 and 2.49 eV, depending on the pentlandite's Fe : Ni content) and display a conduction band energy close to the thermodynamic potential for proton reduction. Despite the limited driving force, a modest activity for photocatalytic H2 has been observed. Our observations show the potential for the future development of pentlandites as photocatalysts. This work provides a basis to explore powerful synergies between biomimetic chemistry and material design to unlock novel applications in solar energy conversion.The authors acknowledge financial support of the Fonds of the Chemical Industry (Liebig grant to U.-P. A.), the Deutsche Forschungsgemeinschaft (Emmy Noether grant to U.-P. A., Cluster of Excellence RESOLV (EXC2033), AP242/2-1; AP242/6-1; MA 5392/7-1), the Fraunhofer Internal Programs under Grant No. Attract 097-602175 as well as the Christian Doppler Association (Austrian Federal Ministry for Digital and Economic Affairs, the National Foundation for Research, Technology and Development) and OMV

Study of the Jupiter system with the Line Emission Mapper probe: Exploring Fundamental Atomic and Plasma Physics in a Natural Laboratory

International audienceThe Jupiter system produces a cornucopia of X-ray emissions, providing a diverse range of invaluable local analogues for bodies and plasmas across the cosmos. These include thermal and non-thermal bremsstrahlung from the aurorae and magnetosphere, charge exchange emissions from the aurorae, Inverse Compton scattering from the radiation belts, X-ray fluorescence (ion-induced and thick-target bremsstrahlung) from the moons and rings, and elastic scattering of solar photons by hydrogen in the atmosphere. Here, we explore how the Line Emission Mapper (LEM) will revolutionise our understanding of these emissions in the 0.2-2.0 keV energy range. In particular, the 1 eV spectral energy resolution provided by the instrument will enable unprecedented access to the charge exchange emissions from Jupiter and the solar emission lines scattered from the jovian atmosphere. We will showcase how LEM's exploration of this natural laboratory will offer access to fundamental atomic physics (e.g. constraining cross-sections for a range of ion species). For the first time, LEM will unambiguously distinguish between the emissions from Iogenic plasma and those from solar wind ions, revealing under what circumstances such systems are open to the solar wind. The extent of this has been debated for decades and has fundamental implications for the nature of rapidly rotating magnetospheres more generally. Through line broadening and Doppler shifts, LEM will also measure the thermal and collisional velocities of the ions at the point of impact with the atmosphere. This will provide valuable new measurements to inform studies of energy transfer in the system and the processes governing Jupiter's aurorae. Alongside planetary science, solar system objects offer the unique opportunity in High Energy Astrophysics of enabling direct comparison between the remotely detected X-ray emissions and in-situ measurements of the precise plasma conditions and processes that generate them. Future missions, such as ESA's JUICE and NASA's Europa Clipper, will make detailed observations across the wider Jupiter system. Using a catalogue of in situ and remote sensing instruments, this next generation fleet of spacecraft will conduct measurements that will offer irreplaceable ground-truths for comparison with LEM's observations of X-ray emissions