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Abstract Nepheline syenites from the ∼1.2 Ga Ilímaussaq Complex of southern Greenland are examined to assess the utility of anisotropy of magnetic susceptibility (AMS) fabrics as proxies for silicate petrofabrics. Mineral lamination is a relatively common structural feature in cumulate rocks, including in the Ilímaussaq intrusion, but there is little consensus on the process (or processes) responsible for its formation. The Ilímaussaq AMS data are combined with rock magnetic experiments and electron backscatter diffraction (EBSD) measurements to characterize the magnetic mineralogy and compare the magnetic fabrics obtained to the silicate petrofabric. The data show that Na-amphibole (arfvedsonite) is most likely the dominant control on the AMS fabrics in the coarse-grained nepheline syenites (referred to as kakortokites), and that the AMS fabric is inverse relative to the observed silicate fabric. The EBSD data for a kakortokite sample suggests that the petrofabric is defined by arfvedsonite and is wholly planar, with evidence of only weak cross-lineation of c axes. The fine-grained nepheline syenites (lujavrites), two of which have a well-developed lamination carried by Na-pyroxene (aegirine), appear to have composite AMS fabrics that are considered to be a consequence of a mixed aegirine (normal) and arfvedsonite (inverse) response. The combined datasets shed light on the mechanisms of fabric acquisition in both lithologies. In the kakortokites, the AMS fabrics and silicate crystallographic preferred orientations, as well as the lack of observed microstructural evidence for subsolidus intra-crystal deformation, support models invoking gravitationally controlled crystal mats in the development of the macro-rhythmic layering of these rocks. In the lujavrites, the strong planar fabrics revealed by both the AMS and EBSD datasets, with some evidence of subsolidus deformation, point to fabric formation and perhaps even aegirine crystallization at the postcumulus stage. The combination of EBSD and AMS fabric datasets is a powerful means of deciphering the processes responsible for mineral alignment in igneous cumulates. 

The title compound, systematic name tris(μ₂-perfluoro-o-phenylene)(μ₂-3-phenyl-4H-chromen-4-one)-triangulo-trimercury, [Hg₃(C₆F₄)₃(C₁₅H₁₀O₂)], crystallizes in the monoclinicP2₁/nspace group with one flavone (FLA) and one cyclic trimeric perfluoro-o-phenylenemercury (TPPM) molecule per asymmetric unit. The FLA molecule is located on one face of the TPPM acceptor and is linked in an asymmetric coordination of its carbonyl oxygen atom with two Hg centers of the TPPM macrocycle. The angular-shaped complexes pack in zigzag chains where they stackviatwo alternating TPPM–TPPM and FLA–FLA stacking patterns. The distance between the mean planes of the neighboring TPPM macrocycles in the stack is 3.445 (2) Å, and that between the benzo-γ-pyrone moieties of FLA is 3.328 (2) Å. The neighboring stacks are interdigitated through the shortened F...F, CH...F and CH...π contacts, forming a dense crystal structure. 

A new pseudopolymorph of berberine, 9,10-dimethoxy-5,6-dihydro-2 H -7λ 5 -[1,3]dioxolo[4,5- g ]isoquinolino[3,2- a ]isoquinolin-7-ylium chloride methanol monosolvate, C 20 H 18 NO 4 + ·Cl − ·CH 3 OH, was obtained during co-crystallization of berberine chloride with malonic acid from methanol. The berberine cations form dimers, which are further packed in stacks. The title structure was compared with other reported solvates of berberine chloride: its dihydrate, tetrahydrate, and ethanol solvate hemihydrate. Hirshfeld analysis was performed to show the intermolecular interactions in the crystal structure of the title compound, and its fingerprint plots were compared with those of the already studied solvates. 

Abstract Spatiotemporally functionalized hydrogels have exciting applications in tissue engineering, but their preparation often relies on radical‐based strategies that can be deleterious in biological settings. Herein, the computationally guided design, synthesis, and application of a water‐soluble cyclopentadienone‐norbornadiene (CPD‐NBD) adduct is disclosed as a diene photocage for radical‐free Diels‐Alder photopatterning. We show that this scalable CPD‐NBD derivative is readily incorporated into hydrogel formulations, providing gels that can be patterned with dienophiles upon 365 nm uncaging of cyclopentadiene. Patterning is first visualized through conjugation of cyanine dyes, then biological utility is highlighted by patterning peptides to direct cellular adhesion. Finally, the ease of use and versatility of this CPD‐NBD derivative is demonstrated by direct incorporation into a commercial 3D printing resin to enable the photopatterning of structurally complex, printed hydrogels. 

The research investigates the thermal behavior of mixed systems based on natural and artificial cellulose fibers used as precursors for carbon nonwoven materials. Flax and hemp fibers were employed as natural components; they were first chemically treated to remove impurities and enriched with alpha-cellulose. The structure, chemical composition, and mechanical properties of both natural and viscose fibers were studied. It was shown that fiber properties depend on the fiber production process history; natural fibers are characterized by a high content of impurities and exhibit high strength characteristics, whereas viscose fibers have greater deformation properties. The thermal behavior of blended compositions was investigated using TGA and DSC methods across a wide range of component ratios. Carbon yield values at 1000 °C were found to be lower for blended systems containing 10–40% by weight of bast fibers, with carbon yield increasing as the quantity of natural fibers increased. Thus, the composition of the cellulose composite affects carbon yield and thermal processes in the system. Using the Kissinger method, data were obtained on the value of the activation energy of thermal decomposition for various cellulose and composite systems. It was found that natural fiber systems have three-times higher activation energy than viscose fiber systems, indicating their greater thermal stability. Blends of natural and artificial fibers combine the benefits of both precursors, enabling the deliberate regulation of thermal behavior and carbon material yield. This approach opens up prospects for the creation of functional carbon materials used in various high-tech areas, including thermal insulation. 

This work presents a general strategy for integrating photoresponsive molecules into liquid crystal elastomers (LCEs) using Diels–Alder chemistry. The method introduces various photochromes, offering a scalable route for multifunctional LCEs. 

A cobalt (II) mononuclear complex was synthesized by two-nitrobenzoic acid and pyrazine-two-carboxamide ligands in the presence of sodium bicarbonate and aqueous solution of cobalt acetate tetrahydrate. The synthesized cobalt(II) complex was characterized by single crystal X-rays diffraction. The coordination geometry of the cobalt complex was octahedral with water molecules occupying the axial sites. A lot of intermolecular interactions were in response to stabilize the supramolecular assembly which were inspected by Hirshfeld surface analysis. Enrichment ratios were calculated to find the pair of atoms having the highest propensity to form crystal packing interactions. Void analysis was conducted to forecast how the crystal would respond to applied stress. Interaction energy calculations were carried out using the B3LYP/6-31G(d,p) electron density model to identify which energy types most significantly contributed to the supramolecular assembly. Moreover, the energy data obtained from DFT calculations showed an average level of stability of the molecule. The moderate HOMO-LUMO energy gap suggested reactivity, while a high electrophilicity index indicates a strong tendency for electron-accepting reactions. 

This study focuses on the development of environmentally sustainable polypropylene (PP)-based composites with the potential for biodegradability by incorporating cellulose and the oligomeric siloxane ES-40. Targeting industrial applications such as fused deposition modeling (FDM) 3D printing, ES-40 was employed as a precursor for the in situ formation of silica particles via hydrolytic polycondensation (HPC). Two HPC approaches were investigated: a preliminary reaction in a mixture of cellulose, ethanol, and water, and a direct reaction within the molten PP matrix. The composites were thoroughly characterized using rotational rheometry, optical microscopy, differential scanning calorimetry, and dynamic mechanical analysis. Both methods resulted in composites with markedly reduced crystallinity and shrinkage compared to neat PP, with the lowest shrinkage observed in blends prepared directly in the extruder. The inclusion of cellulose not only enhances the environmental profile of these composites but also paves the way for the development of PP materials with improved biodegradability, highlighting the potential of this technique for fabricating more amorphous composites from crystalline or semi-crystalline polymers for enhancing the quality and dimensional stability of FDM-printed materials.