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Lignocellulose fiber obtained from high-altitude plant species Daphne bholua and Daphne papyracea, locally named Lokta bushes, is used in Asian regions to fabricate high-quality handmade paper sheets, packaging materials, composites, and paper bills. A systematic study on the material properties of the fiber to explain the performance of Lokta fiber–based materials has not been reported yet. In this study, the physio-chemical properties of untreated and 1%, 3%, 6%, and 9% NaOH (w/v)-treated Lokta fiber were systematically investigated at ambient temperature. The retting efficiency and cellulose content increased with alkali concentration followed by a decrease in lignin, hemicellulose, and extractives. This observation was consistent with the reduction of lignin and hemicellulose characteristics peaks in the FTIR, a reduction of effective fiber bundle width, and an increase in fiber density. High-resolution scanning electron microscope (SEM) images showed that alkali treatment results in significant loss of cementing materials and separation of fiber bundles. Alkali retting also increased the crystallinity index, tensile strength, and thermal stability. The degradation temperature for untreated, 6% NaOH treated, and 9% NaOH treated samples was found to be 325 °C, 343 °C, and 347 °C; respectively. The findings of this study will be important to optimize the end properties of the Lokta fiber–based paper and composite materials. 

Glucose biosensors are widely used for clinical, industrial, and environmental applications. Nonenzymatic electrochemical glucose biosensors based on metal oxides with a perovskite structure have exhibited high sensitivity, excellent stability, and cost efficiency. In this work, porous La–Sr–Co–Ni–O (LSCNO) nanofibers, with an ABO 3 -type perovskite structure, were prepared through optimizing the A-site and B-site elements by electrospinning, followed with calcination at 700 °C for 5 h. Characterized by scanning and transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy, fabricated nanofibers were confirmed to be porous and nanosized polycrystalline grains with high crystallinity. A novel La 0.75 Sr 0.25 Co 0.5 Ni 0.5 O 3 -based nonenzymatic electrochemical biosensor was developed, which is sensitive to glucose because of an electrochemically catalytic mechanism, a mediated electron transfer involving Ni( ii )/Ni( iii ) or Co( ii )/Co( iii ), accompanying with gluconic acid complexation. The glucose biosensor presented a linear response in the range of 0.1–1.0 mM with a calibration sensitivity of 924 ± 28 μA mM −1 , a proportion of the variance of 0.9926, and a lower limit of detection of 0.083 mM, respectively, demonstrating an outstanding analytical performance. The biosensor showed no response to the most widely used anionic surfactant, sodium dodecyl sulfate, and low sensitivity to other biomolecules, such as fructose, lactose, galactose, mannose, dopamine, and ascorbic acid. A urine sample was tested by this novel nonenzymatic electrochemical biosensor by standard addition method, suggesting a potential application for clinical test. 

Abstract Compared to halides Cs₂HfX₆(X = Cl, Br, I) with a vacancy‐ordered cubic double perovskite structure, the halide Cs₂HfF₆(CHF), with a hexagonal Bravais lattice, possesses a higher mass density and chemical stability for radiation detection. Luminescence properties and energy transfer mechanisms of rare‐earths‐doped CHF materials are studied here. The structure of CHF is identified as a new type of vacancy‐ordered hexagonal perovskite, with the same type of building blocks of the double perovskite but stacked with single layers. Density‐functional theory calculations reveal a large bandgap of CHF. A broad emission is observed from the pristine CHF host, which is suggested to be associated with self‐trapped excitons (STEs). A series of rare‐earths‐doped materials are designed utilizing the STE emissions, and efficient energy transfers from STEs and Tb³⁺to Eu³⁺are achieved for tunable emissions. The codoped material shows stable emission under X‐ray irradiation, with 10.2% reduction from its initial emission intensity, associated with possible structural evolution by radiation‐induced deformation of the soft host. The radiation responses of singly and codoped materials are evaluated, and the codoped material is found to be more sensitive to the radiation energy than the singly doped or pristine CHF for radiation detection.