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This study builds upon our experience with electrocatalyzed dearomatization of lignin in aqueous systems, which has shown to produce sodium levulinate, sodium 4-hydroxyvalerate, sodium acetate, and sodium formate as major products. Here, we extend this investigation by exploring a water/γ-valerolactone (GVL) solvent system for electrochemical depolymerization and dearomatization of lignin, using Na2CO3 as electrolyte. GVL, derived from biomass, has frequently been employed for biomass treatment, notably in the Organosolv process. Consequently, various biorefinery strategies have emerged utilizing GVL as a green platform, primarily for its potential in delignifying lignocellulosic biomass when combined with water and dilute acid. This study proposes electrochemical depolymerization of lignin in GVL as a step toward the concept of a bioelectrorefinery, aiming to convert lignin into aliphatic organic chemicals. Consistent with our prior work in aqueous systems, applying a current of −100 mA over 8 h yielded sodium levulinate, sodium 4-hydroxyvalerate, sodium acetate, and sodium formate. Confirmation was provided by liquid chromatography electrospray ionization high-resolution mass spectrometry, nuclear magnetic resonance, and infrared spectroscopy. These findings advance our understanding of GVL as a biomass-based platform, highlighting its potential not only for biomass treatment but also as a medium for converting lignin into valuable aliphatic chemicals.

Masked stereolithography printing can be used to produce functionalised magneto-responsive polymer structures. Magnetic filler additivation of the photopolymer enables the production of powerful and fast soft robotics. However, current approaches require high filler concentrations, reducing the mechanical properties and compromising the processability. In this study, FeNi nanoparticles were added to a photopolymer to take advantage of their soft magnetic response and high magnetisation. Field-assisted printing gives rise to magnetic anisotropy by arranging laser-synthesised FeNi nanoparticles into uniaxial magnetic strands of up to 500 μm length. Favoured by the small size and even distribution of the nanoparticles, only 0.02 wt% are needed to detect magnetic responsivity. Thus, the impact on the mechanical property is reduced while facilitating the control over the composite magnetic properties. The practical feasibility of the composites is demonstrated by actuating gripper and impeller structures which offer possibilities in applications like drug delivery and tissue engineering.

Additive manufacturing of plastic components in medical technology enables greater freedom of design when designing patient-specific products, in particular, in production of customised medical products, such as orthoses. In the present contribution, the advantages of a digital process chain are combined, from the 3D scan of the patient to CAD-supported modelling of the corrective form and the orthosis design until the path planning of a printable geometry. The main disadvantages of current additive printing techniques, such as the fused filament fabrication (FFF) process, are high printing times (>12 h) for larger components as well as the low degree of freedom in the 2.5D printing technique that prevent the subsequent application of geometry features to the product. The fast SEAMHex (Screw Extrusion Additive Manufacturing) printing technology with a hexapod kinematic printing bed provides a solution to the mentioned difficulties. Consequently, the high-performance printer has been prepared for the individual requirements of medical technology in terms of materials and geometries. An effective additive manufacturing process has been realised and tested in combination with a digital process chain for orthosis modelling.

Quaternary metal oxynitride-based photoanodes with a large light transmittance are promising for high solar-to-hydrogen (STH) conversion efficiency in photoelectrochemical (PEC) tandem cells. Transparent substrates to support PEC water-splitting were fabricated using atomic layer deposition (ALD) to synthesize 30 and 60 nm GaN on SiC substrates. A generalized approach was used to grow a quaternary metal oxynitride, i.e. SrTaO2N thin film on the GaN/SiC substrates. The transparency above 60% in the wide solar spectrum highlights its availability of transmitting visible light to the rear side. A photocurrent onset at ca. −0.4 V vs. reversible hydrogen electrode (RHE) was achieved by the SrTaO2N/GaN/SiC photoanodes in a 0.1 M NaOH electrolyte under simulated solar irradiation. This paves the way for the construction of hierarchically nanostructured tandem PEC cells. This work demonstrates the viability of integrating ALD in constructing substrates for semi-transparent quaternary metal oxynitride photoanodes.

Abstract Gallium nitride (GaN) is a key material when it comes to light-emitting diodes (LEDs) and has pushed the LED revolution in lighting and displays. The concept of down-conversion of a GaN-based blue LED offers the possibility to provide efficient generation of monochromatic, high-color purity light resulting in a highly efficient warm-white all-nitride phosphor-converted light emitting diode (pc-LED). Although the down conversion of blue light from InGaN LEDs has become a dominant technique for producing white light, there are still some technical challenges, e.g. the immiscibility of GaN and InN and the lattice mismatch between the substrate and InGaN, that have to be overcome. Here we demonstrate the doping of bulk GaN with europium, terbium and the combination of both resulting in intriguing luminescence properties, pushing the role of GaN:Eu,Tb as a chief component in future light emitting diodes. This colour tuning proves that one luminescence host can provide three colours (red, green and orange) and that even the so called “yellow gap” could be closed with a III-nitride. By using one material for all colours, it will be possible to overcome the technical challenges in building up LED devices, which will open up new capabilities for modern highly efficient phosphors.

Research towards the production of renewable chemicals for fuel and energy industries has found lignin valorization as key. With a high carbon content and aromaticity, a fine-tuning of the depolymerization process is required to convert lignin into valuable chemicals. In context, model compounds have been used to understand the electrocatalyzed depolymerization for mimicking the typical linkages of lignin. In this investigation, 2-phenoxyacetophenone, a model compound for lignin β-O-4 linkage, was electro-catalytically hydrogenated (ECH) in distinct three-electrode setups: an open and a membrane cell. A deep eutectic solvent based on ethylene-glycol and choline chloride was used to pursue sustainable routes to dissolve lignin. Copper was used as electrocatalyst due to the economic feasibility and low activity towards hydrogen evolution reaction (HER), a side reaction of ECH. By varying the cell type, we demonstrate a simple ECH route for the generation of different monomers and oligomers from lignin. Gas chromatography of the products revealed a higher content of carbonyl groups in those using the membrane cell, whereas the open cell produced mostly hydroxyl-end chemicals. Aiming at high value-added products, our results disclose the cell type influence on electrochemical reductive depolymerization of lignin. This approach encompasses cheap transition metal electrodes and sustainable solvents.

ABSTRACTPhotoluminescent carbon nanoparticles (CNPs), such as carbon dots (CDs), have attracted much attention owing to a unique set of properties, like high and tunable fluorescence. In this way, the use of carbon-rich lignin has been demonstrated to be a sustainable approach to producing a broad range of photoluminescent CNPs. However, the valorization of this complex polyphenol is limited when it comes to green and efficient ways of conversion. In addition, the existing solvothermal approaches using lignin often result in CDs with low photoluminescence, while flammable and/or toxic solvents are employed. Here, we depolymerized technical lignins, i.e. kraft and soda, through electroreductive cleavage in two different sustainable media: deep eutectic solvent and levulinic acid. After depolymerization, lignin-derived monomers were generated, with a predominance of aryl ether and phenolic groups, which were further combined with 1,2-Phenylenediamine to produce N-doped CNPs in a solvent-free approach. Photoluminescent CNPs with varied sizes were generated (5–50 nm), which presented a wide photoluminescence emission, from blue to red, depending on solvent polarity. These results demonstrate a feasible and sustainable route for the solvent-free synthesis of photoluminescent CNPs using lignin-derived monomers as carbon source, which may find applications in a wide range of fields.

Introduction: Our society faces new challenges nowadays. The widespread usage of mobile communications and its availability attracts more and more users to the worldwide network. The current generation is unable to isolate themselves from their internet connected gadgets. Clearly, the world is becoming more and more digital and dependent on information and communication technology (ICT). On the one hand, it gives the opportunity to communicate and removes all borders between cities and even continents. On the other hand, youth over-dependence on technology could lead to impaired consciousness, change in mental processes, and the problems of the Googlization of our society. The formation of young people’s social capital in the modern society is influenced by information and communication technology and new communication possibilities. Notably, the transformation of communication processes was caused not only by the common availability of communication means and constantly growing network coverage areas, but also by the availability of social networks as the main means of communication among youngsters. Due to the COVID-19 pandemic and self-isolation, communication between young people has become even more dependent on ICT. The means and ways of the formation of human and social capital have also changed. Aim: The main aim of the research is the evaluation of the influence of information and communication technology on the formation of social capital of young people, as well as the study of the amount of time spent on ICT usage for studying versus communication during the COVID-19 pandemic. Materials and methods: This research was conducted among young people ages 18-38 and involved more than 500 participants (46% of whom were men and 54% women), who work or study in small or medium-sized cities, as well as in rural areas in the south east of the Moscow Region (Russia). The survey was conducted in the beginning of 2021 (after Russia lifted its lockdown restrictions). Participants were as follows: 21% were secondary school students, 35% were higher education students, 26% were college students, and 18% were working youth. The methods used were custom survey, data processing algorithm, and a part of the longitudinal analysis toolbox known as, “The influence of information and communication technology on youth’s health”. Results: To compare the research results (based on the custom longitudinal analysis toolbox, which has been used for 10 years in this region), the data for 2020 (before the COVID-19 pandemic) and 2015 were used. The results showed that information and communication technology have become the main means of communication in the modern society during the pandemic, its use pervades all areas, from distant learning to working from home. Also, while modern technology provided more ways of communication even before the pandemic, it also became the main means of communication, especially during the period of hard lockdowns, thereby, helping to preserve and develop social capital. The pandemic also showed the difference in the access to and the usage of ICT by individuals and households. Particularly, people in areas with poor network coverage have a lower possibility of using internet-connected mobile devices. In addition, the percentage of people using information and communication technology for studying has grown up to 76% during the pandemic. Almost half of the survey participants started communicating with friends using information and communication technology more often during their self-isolation. While 13% of all participants think it is easier to use ICT to communicate, 90% of all respondents use social media for communication. Conclusions: The pandemic triggered the development and wider usage of information and communication technology, which influence the formation of social capital greatly. The digitalization processes that took place before COVID-19 have strengthened information processes. Opportunities for the formation of social capital of young people have changed as they adapted to the pandemic restrictions (and distancing) that was imposed on the society. The consequences of such changes require a special attention and further research. This research represents a kind of iteration on this complex topic, and it should be analyzed further.

Greenland's bed topography is a primary control on ice flow, grounding line migration, calving dynamics, and subglacial drainage. Moreover, fjord bathymetry regulates the penetration of warm Atlantic water (AW) that rapidly melts and undercuts Greenland's marine-terminating glaciers. Here we present a new compilation of Greenland bed topography that assimilates seafloor bathymetry and ice thickness data through a mass conservation approach. A new 150 m horizontal resolution bed topography/bathymetric map of Greenland is constructed with seamless transitions at the ice/ocean interface, yielding major improvements over previous data sets, particularly in the marine-terminating sectors of northwest and southeast Greenland. Our map reveals that the total sea level potential of the Greenland ice sheet is 7.42 ± 0.05 m, which is 7 cm greater than previous estimates. Furthermore, it explains recent calving front response of numerous outlet glaciers and reveals new pathways by which AW can access glaciers with marine-based basins, thereby highlighting sectors of Greenland that are most vulnerable to future oceanic forcing.

BackgroundThe constant growth of interest in hybrid coronary artery revascularization (HCR) is apparent. Yet, few studies report outcomes of the one-stage HCR. Consequently, the status of such procedures is not adequately supported in clinical guidelines. The aim of this study was to report the safety, feasibility, and long term-outcomes of the one-stage HCR.Methods and resultsPatients were enrolled in the prospective one-stage hybrid coronary revascularization program (HYBRID-COR). They underwent a one-stage hybrid revascularization procedure while on double antiplatelet therapy (DAPT) with Ticagrelor: endoscopic atraumatic coronary artery bypass grafting (EACAB) for revascularization of the left anterior descending (LAD) artery and percutaneous intervention in non-LAD arteries with contemporary drug-eluting stents. The composite primary endpoint included MACCE (major adverse cardiac and cerebrovascular events: death, myocardial infarction, stroke, and repeated revascularization) in long-term observation. The study cohort consisted of 30 patients (68% male) with stable coronary artery disease (26.7%) and unstable angina (73.3%). Procedural success was 100%. No death, myocardial infarction (MI), or stroke were observed in the perioperative period. One patient (3.3%) required chest revision and blood transfusion due to surgical bleeding. Kidney injury was noted in two patients (6.6%). In a long-term follow-up (median; IQR: 4.25; 2.62–4.69 years), two patients (6.6%) underwent repeated revascularization and one patient (3.3%) died due to MI. The overall primary endpoint rate was 9.9%.ConclusionOne-stage hybrid revascularization, on DAPT, is a feasible, safe, and efficient way of achieving complete revascularization in selected patients. The complication rate is low and acceptable. Further randomized trials are required.

The achievement of frictionless systems, known as superlubricity, has become of great importance concerning energy saving and emission reduction. In parallel, the drive toward sustainability and environmental aspects has led to intense advances in the research and development of biobased materials. From the standpoint of Green Chemistry principles, this review presents a critical overview of the latest findings and future perspectives on the application of biobased materials aiming at superlubricant pursuits. The progress in the use of biomacromolecules, such as chitosan, cellulose, and lignin, as additives to lubricants or coating materials, are addressed, as well as the advances on sustainable coatings based on diamond-like carbon (DLC). Deeper investigations on the development of non-hazardous processes dedicated to the tribological properties of DLC, such as electrochemical synthesis using environment-friendly solvents to generate molecular precursors, widen the perspectives to achieve sustainable materials. Besides, the exploration of the tribochemical interactions between the DLC surface and lubricants containing biobased materials arises as a promising strategy to achieve green superlubricity as a viable and scalable process, through different pathways: by hydrogen bonds between lubricant and additives, via surface passivation of the functional groups present in these biomacromolecules or by biomimicking natural joints.

Replacing crude oil as the primary industrial source of carbon‐based chemicals has become crucial for both environmental and resource sustainability reasons. In this scenario, wood arises as an excellent candidate, whilst depolymerization approaches have emerged as promising strategies to unlock the lignin potential as a resource in the production of high‐value organic chemicals. However, many drawbacks, such as toxic solvents, expensive catalysts, high energy inputs, and poor product selectivity have represented major challenges to this task. Herein, we present an unprecedented approach using electrocatalysis for the simultaneous depolymerization and dearomatization of lignin in aqueous medium under ambient conditions. By employing water/sodium carbonate as a solvent system, we demonstrated a pathway for selectively depolymerizing lignin under reductive electrochemical conditions using carbon as an electrocatalyst. After reductive electrocatalysis, the presence of aromatic compounds was no longer detected via nuclear magnetic resonance (NMR) spectroscopy. Further characterization by NMR, FTIR spectroscopy, and mass spectrometry revealed the major presences of sodium levulinate, sodium 4‐hydroxyvalerate, sodium formate, and sodium acetate as products. By achieving a complete dearomatization, valuable aliphatic intermediates with enhanced reactivity were selectively obtained, opening new avenues for further synthesis of many different organic chemicals, and contributing to a more sustainable and circular economy. [ABSTRACT FROM AUTHOR]

Additive manufacturing of plastic components in medical technology enables greater freedom of design when designing patient-specific products, in particular, in production of customised medical products, such as orthoses. In the present contribution, the advantages of a digital process chain are combined, from the 3D scan of the patient to CAD-supported modelling of the corrective form and the orthosis design until the path planning of a printable geometry. The main disadvantages of current additive printing techniques, such as the fused filament fabrication (FFF) process, are high printing times (>12 h) for larger components as well as the low degree of freedom in the 2.5D printing technique that prevent the subsequent application of geometry features to the product. The fast SEAMHex (Screw Extrusion Additive Manufacturing) printing technology with a hexapod kinematic printing bed provides a solution to the mentioned difficulties. Consequently, the high-performance printer has been prepared for the individual requirements of medical technology in terms of materials and geometries. An effective additive manufacturing process has been realised and tested in combination with a digital process chain for orthosis modelling. [ABSTRACT FROM AUTHOR]

The development of sustainable valorization methods for lignin is a challenging task because the vast majority of the reported studies involve either harsh conditions or expensive transition metal catalysts. Inspired by the sunlight degradation of lignin compounds, known as lignin yellowing, the use of a commercially available cheap organic photoinitiator, namely, phenacyl bromide (PAB) is reported here, for the efficient cleavage of lignin model compound 2‐phenoxyacetophenone (2‐PAP) and for the depolymerization of soda pulped lignin (SL) under UV‐A irradiation and ambient conditions. Real‐time NMR investigations of the photoreaction between 2‐PAP and PAB shed light on the possible reaction mechanisms involving different radical species, HBr, and molecular oxygen. Interestingly, combined spectral, chromatographic, powder X‐ray diffraction, and thermal studies of the photoreaction between PAB and SL indicate the formation of guaiacyl alcohol as the main product. The unprecedented performance of PAB is attributed to the excess generation of phenacyl radicals, the generation of photolabile brominated species, and HBr playing key roles in the cleavage of β‐O‐4 linkages. This work represents a new edge for sustainable lignin valorization under mild reaction conditions and offers the opportunity for large‐scale production of valuable aromatics using technical lignins as feedstock. [ABSTRACT FROM AUTHOR]