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Abstract: The incorporation of nitrogen (N) and hydrogen (H) into the diamond lattice is a fundamental aspect of diamond growth and defect chemistry. While these impurities are typically linked to parental fluids composition, the influence of encapsulated mineral phases on defect distribution remains largely unexplored. This study utilizes synchrotron radiation micro-Fourier transform infrared mapping to resolve the spatial interplay between N and H impurities and mineral inclusions (sulfide, garnet, and graphite) in four eclogitic diamonds from the Yakutian field, Siberian craton. Mapping of the characteristic infrared absorption bands reveals significant point-defect heterogeneities localized at the inclusion-diamond interfaces. A coupled increase in N- and H-related absorbance is uniquely associated with sulfide inclusions, suggesting that sulfides may act as a local source (or sink) for these species during (and following) the entrapment. In contrast, proximity to garnet and graphite only correlates with localized enrichment of H-related defects (specifically the 3107 cm−1, 1405 cm−1, and 3236 cm−1 bands). Previous studies on N and H incorporation in minerals at high pressures and temperatures support our interpretations. In particular, H- enriched zones extend tens of micrometers into the host lattice, indicating that the effective diffusivity of H is either slowed by deep trapping mechanisms (e.g., formation of stable Csingle bondN and Nsingle bondH complexes) or that the H enrichment halos record a transient re-equilibration with the diamond growth medium. In contrast, a sluggish kinetic would explain the occurrence of nitrogen halos observed adjacent to sulfide inclusions; a continuous, high-concentration chemical source is required to sustain a localized, measurable gradient against billions of years of potential relaxation. These findings provide new insights into the factors governing the spatial distribution and abundance of impurities in diamonds, with broader implications for understanding defect incorporation in both natural and synthetic systems.

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Abstract: Measuring live cells by FTIR spectroscopy is challenging due to their small size and the absorbance of water in the mid-IR region. However, measuring cells in their live state is important to observe changes in the biological processes of cells that are unaffected by fixation and drying processes. Recently, ZnS hemispheres were used to sandwich live cells in a 6 µm layer of cell medium, which simultaneously limit the absorbance of water and increase the spatial resolution by x2.25, thereby enabling high quality spectra to be acquired from living cells. So far, this method has been used as an imaging technique to showcase the distribution of biomolecules within a single cell. In this work, we present an alternative use of these ZnS hemispheres as a high throughput screening tool. We obtained high quality spectra of a single cell at a measurement rate of ∼1 min/cell. We’ve applied this technique to observe the biochemical effects of various polystyrene microplastics on two mammalian cell lines (J774A.1 and A549), however the method can easily be expanded to other cell lines, microplastics, and alternative xenobiotics.

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Abstract: The desulfurization of flue gas requires sorbents capable of selective and reversible SO2 capture. However, top-performing materials operate through either strong binding sites or the use of narrow pores, leading to difficulties in desorption and materials regeneration. Here, we report the efficient capture of trace SO2 using a robust and scalable aluminum-based metal–organic framework, MIL-120, which shows an exceptional SO2 uptake of 2.1 mmol g–1 at 2500 ppm and 298 K, coupled with optimal heats of adsorption (19–42 kJ mol–1) and fully reversible desorption at room temperature. Direct visualization of adsorbed SO2 molecules reveals host–guest and guest–guest interactions, collectively affording an SO2 packing density of 1.92 g cm–3, formally surpassing that of solid SO2 (1.62 g cm–3). Breakthrough experiments demonstrate that MIL-120 exhibits remarkable trace SO2 capture in the presence of dry or wet NO2 (another corrosive gas present in flue gas) with a record dynamic selectivity of 124, confirming the potential for MIL-120 to separate SO2/NO2 mixtures. This work sets a new benchmark for sorbent materials for reversible trace SO2 capture and separation.

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Abstract: A facile approach is demonstrated for synthesizing a mechanically tough ZIF-71 [Zn(dcIm)2; dcIm = 4,5-dichloroimidazole] monoliths with a polymer binder, employing namely poly-methyl methacrylate (PMMA) through a sol-gel process. The addition of a slight polymer binder (∼10 wt.%) to the sol-gel mixture is shown to enhance the mechanical properties such as the elastic modulus, hardness, fracture toughness, strain hardening, and creep behavior of the composite monoliths compared to the pure ZIF-71 monoliths. Nitrogen sorption measurements revealed that the composite monoliths have a high surface area (∼350 m2/g) although it was reduced from ∼600 m2/g due to pore blockage by the polymer. Composite monoliths exhibit less surface cracks and are relatively stiffer but are notably tougher than the pure ZIF-71 monoliths as the fracture toughness tripled from around 0.15 MPa m1/2 to around 0.45 MPa m1/2. Despite the incorporation of a small quantity of polymer in the monolith, this has a significant impact on increasing the mechanical stiffness, hardness and fracture resistance of the resulting monoliths. Creep response observed under a constant load revealed the presence of PMMA incorporated in the composite monolith. Nearfield infrared (IR) nanospectroscopy via nanoFTIR and pseudoheterodyne (PsHet) scattering-Scanning Nearfield Optical Microscopy (s-SNOM) IR imaging on plastically deformed and indented surfaces revealed local chemical structure-mechanical interactions. Our findings suggest that the polymer chains are trapped inside the ZIF-71 structure, thereby improving the mechanical resilience that might pave the way to future scaling up of MOF monoliths for practical applications and durable devices.

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Abstract: The empty, extensive low-density lattice topology of hemoglycin is examined to understand how in space, and possibly as early as 800 Myr into cosmic time a rod-like polymer of glycine and iron came into dominance. A central question to be answered is whether the hemoglycin rod lattice with diamond 2H symmetry represents the most efficient covering of space by a regular arrangement of identical rods. Starting from the tetrahedral symmetry of every hemoglycin lattice vertex we find that the regular truncated tetrahedron of Archimedes may be expanded until neighbouring hexagon faces are coincident, at which point space filling is 23/24 or 95.8333 per cent complete. We describe the unit cells of the diamond 2H rod lattice and its conforming near-complete space-filling structure, which has identical symmetry. Maximum space filling via a minimum of molecular material can allow hemoglycin to drive accretion in molecular clouds, contributing to the composition of dust, and providing a background for its widespread presence in meteoritic samples and in cometary material that falls to Earth. The optical properties of hemoglycin lattice entities are derived from quantum calculations of ultraviolet (UV) and visible transition energies and strengths. The hemoglycin extinction curve duplicates the nominal 218 nm UV absorption feature known as the UV bump, together with two visible absorption features present in a generic compilation of astronomical extinction data.