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α-Alkylidene cyclic carbonates (αCCs) are gaining interest as building blocks in organic and polymer chemistry. To date, their synthesis via the coupling of CO2 to propargylic alcohols has been restricted to batch processes, with extensive efforts devoted to improving catalytic systems. Herein, utilizing a refined, homogeneous silver–carbene–organobase catalytic system, we optimized batch conditions to achieve, for the first time, complete conversion of tertiary propargylic alcohols within minutes instead of hours. Building on this, we introduce a continuous flow methodology to produce a library of αCCs, achieving the highest space–time yields reported, with quantitative conversions in less than 20 minutes and outputs up to 111 grams per day. This approach reduces CO2 usage to 1 or 2 equivalents, improves parameter control, and is expected to facilitate scalability. In addition, "plug-and-play" lab-scale continuous flow modules enable seamless integration of subsequent αCC transformations without intermediate purification, as illustrated by the aminolysis of αCCs into oxazolidones with good conversion (91%). Furthermore, supporting the silver–carbene catalyst on a polymer matrix eliminates silver contamination and even suppresses the need for a base co-catalyst. This work advances the scalable synthesis of αCCs via continuous flow, marking a significant step toward greener, CO2-based cyclic carbonates and derivatives. [ABSTRACT FROM AUTHOR]

Spearing mantis shrimps are aggressive crustaceans using specialized appendages with sharp spikes to capture fishes with fast movement. Each spike is a biological tool that has to combine high toughness, as required by the initial impact with the victim, with high stiffness and strength, to ensure sufficient penetration while avoid breaking.We performed a multimodal analysis to uncover the design strategies of this harpoon based on chitin. We found that the spike is a slightly hooked hollow beam with the outer surface decorated by serrations and grooves to enhance cutting and interlocking. The cuticle of the spike resembles a multilayer composite: An outer heavily mineralized, stiff, and hard region (with average indentation modulus and hardness of 68 and 3 GPa), providing high resistance to contact stresses, is combined with a less mineralized region, which occupies a large fraction of the cuticle (up to 50%) and features parallel fibers oriented longitudinally, enhancing stiffness and strength. A central finding of our work is the presence of a tiny interphase (less than 10 μm in width) based on helical fibers and showing a spatial modulation in mechanical properties, which has the critical task to integrate the stiff but brittle outer layer with the more compliant highly anisotropic parallel-fiber region.We highlighted the remarkable ability of this helicoidal region to stop nanoindentation-induced cracks.Using three-dimensional multimaterial printing to prototype spike-inspired composites, we showed how the observed construction principles can not only hamper damage propagation between highly dissimilar layers (resulting in composites with the helical interphase absorbing 50% more energy than without it) but can also enhance resistance to puncture (25% [ABSTRACT FROM AUTHOR]

In pharmaceutical applications, the porous particles of organic compounds can improve the efficiency of drug delivery, for example into the pulmonary system. We report on the successful preparation of macroporous spherical granules of mannitol using a spray-drying process using polystyrene (PS) beads of ~340 nm diameter as a sacrificial templating agent. An FDA-approved solvent (ethyl acetate) was used to dissolve the PS beads. A combination of infrared spectroscopy and thermogravimetry analysis proved the efficiency of the etching process, provided that enough PS beads were exposed at the granule surface and formed an interconnected network. Using a lab-scale spray dryer and a constant concentration of PS beads, we observed similar granule sizes (~1–3 microns) and different porosity distributions for the mannitol/PS mass ratio ranging from 10:1 to 1:2. When transferred to a pilot-scale spray dryer, the 1:1 mannitol/PS composition resulted in different distributions of granule size and porosity depending on the atomization configuration (two-fluid or rotary nozzle). In all cases, the presence of PS beads in the spray-drying feedstock was found to favor the formation of the α mannitol polymorph and to lead to a small decrease in the mannitol decomposition temperature when heating in an inert atmosphere. [ABSTRACT FROM AUTHOR]

Raman spectroscopy is a commonly applied technique for identifying the molecular nature of the constituents of solid samples. However, the quantification of the intensity associated with a particular molecular solute in solid dispersions requires analytical strategies to integrate the possible microheterogeneity in terms of composition. Many quantitative applications of solid dispersions rely on large spectral datasets. However, analytical procedures with limited data acquisition must be developed in preparation for future robotic planetary exploration missions or for field applications on earth, both of which involve miniaturised instrumentation. Based on statistical models, we evaluate the minimum number of spectra required to deliver robust data for quantitative measurements associated with differing concentrations of β‐carotene or L‐cysteine dispersed in gypsum. In this respect, reference materials were prepared, and we investigated an analytical methodology based on a large, automated multipoint scanning approach enabling the representative interrogation of the samples. We demonstrate from a comprehensive and reproducible model that the intensity associated with different organic contents within a mineral matrix can be estimated from a reduced number of spectra. Calibration curves were established for our reference dispersions of L‐cysteine in gypsum in the range 1–10 wt%, using both confocal benchtop and nonconfocal miniaturised portable instruments. We propose a reference system and a Raman analytical strategy, that is, adaptable for planetary exploration constraints, and which allows quantitative comparison of performance of instrumentation in terms of signal detection. [ABSTRACT FROM AUTHOR]

In this work, NaFePOF-carbon composite powders were prepared by spray-drying a solution of inorganic precursors with 10 and 20 wt% added carbon black (CB) or carbon nanotubes (CNTs). In order to compare the effect of CB and CNT when added to the precursor solutions, the structural, electrochemical, and morphological properties of the synthesized NaFePOF-xCB and NaFePOF-xCNT samples were systematically investigated. In both cases, X-ray diffraction shows that calcination at 600 °C in argon leads to the formation of NaFePOF as the major inorganic phase. Fe Mössbauer spectroscopy was used as complementary technique to probe the oxidation states, local environment, and identify the composition of the iron-containing phases. The electrochemical performance is markedly better in the case of NaFePOF-CNT (20 wt%), with specific capacities of about 100 mAh/g (NaFePOF-CNT) at C/4 rate vs. 50 mAh/g for NaFePOF-CB (20 wt%). SEM characterization of NaFePOF-CB particles revealed different particle morphologies for the NaFePOF-CNT and NaFePOF-CB powders. The carbon-poor surface observed for NaFePOF-CB could be due to a slow diffusion of carbon in the droplets during drying. On the contrary, NaFePOF-CNT shows a better CNT dispersion inside and at the surface of the NFPF particles that improves the electrochemical performance. [ABSTRACT FROM AUTHOR]

Rechargeable aqueous zinc-ion battery (ZIB) is regarded as a strategic technology for energy storage and conversion in high-power, high-safety applications. Nonetheless, the primary challenge lies in the development of high-performance cathode materials. In this work, we report for the first time a self-standing V 2 O 5 /polydopamine/CNT (V 2 O 5 /PDA/CNT) electrode that shows outstanding electrochemical performance as cathode material for zinc-ion batteries. A polydopamine coating was applied to the surface of V 2 O 5 particles through a facile self-polymerization process of dopamine. The PDA coating was confirmed and studied by TEM, TGA, FTIR-ATR, and XPS (O 1s & V 2p, C 1s and N 1s). Polydopamine thin layer leads to the partial reduction of V5+ to V4+. Combining V 2 O 5 /PDA with CNT allowed us to obtain a self-standing, binder-free cathode material with a high capacity of ∼ 530 mAh g−1 at 0.1 A g−1. The developed electrode demonstrates excellent rate capability. Indeed, even with a 25-fold increase in current density (from 0.2 A g−1 to 5 A g−1), V 2 O 5 /PDA/CNT-b retains 94 % of its capacity. In addition, the new electrode exhibits long-term cycle stability enduring up to 1000 cycles at high current density with excellentcapacity retention. The combination of PDA coating with the incorporation of carbon nanotube appears to be an excellent strategy for enhancing the electrochemical performance and stability of V 2 O 5 for ZIBs. • V 2 O 5 /polydopamine/CNT electrode is prepared by self-polymerization. • Polydopamine surface protective layer enhances the performance of V 2 O 5 material. • V 2 O 5 /polydopamine/CNT electrode exhibits excellent electrochemical performance. [ABSTRACT FROM AUTHOR]