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关键词： Cation vacancies   Electrochemical reaction   Metal ion doping   Positron annihilation   VO2(B)  

摘要： Iron-doped VO₂ nanorods (V_1-xFe_xO₂) containing oxygen and cation vacancies were successfully fabricated via a simple one-step hydrothermal technique. XRD characterization shows that the lattice contraction arises from metal cation doping. When evaluate as an electrode material, these iron-doped VO₂ nanorods exhibit improved energy storage performance compared with pure VO₂. Specifically, the specific capacitance of the V_1-xFe_xO₂ (x = 0.005) sample is 47.2 mAh/g at 0.1 A/g, and the V_1-xFe_xO₂ (x = 0.005) also delivers the highest specific capacity, maintaining 81.85% of its capacitance retention after 1000 cycles at 1.0 A/g. The mechanism underlying the enhancement of electrochemical performance was investigated using XPS spectra and positron lifetime annihilation spectroscopy (PLAS). The results suggest that Fe³⁺ doping increases the concentrations of both oxygen and cation vacancies, which contributes to the improvement of electrochemical performance. This work shows that the doping of iron ions with smaller radius and lower valence state can introduce oxygen vacancies as well as cation vacancies, thus significantly improve the electrochemical performance of VO₂. The study demonstrates that cation doping represents a viable strategy for optimizing the electrochemical performance of electrode materials.

关键词： Fluorides   LiYF4 ceramics   Microwave dielectric properties  

摘要： Non-stoichiometric Li_(1+x)YF_(4+x) (x = 0.00, 0.03, 0.05, 0.07) ceramics were synthesized via the solid-state reaction route to explore their structural evolution, densification behavior, and microwave/millimeter-wave dielectric performance. By compensating LiF volatilization during sintering, the formation of the Y₆O₅F₈ secondary phase was effectively suppressed. X-ray diffraction and Rietveld refinement confirmed the tetragonal scheelite-type LiYF₄ phase (space group I41/a), with the minimum secondary-phase content (0.58%) achieved at x = 0.03. The ceramics exhibited excellent densification, attaining a maximum relative density of 97% at a low sintering temperature of 700 °C—substantially reduced compared with unary fluoride YF₃. The optimized composition (x = 0.03) demonstrated superior dielectric properties: ε_r = 9.4, Qf = 16,234 GHz at ∼22 GHz, and τ_f = –54.2 ppm/°C. Infrared reflectance spectra revealed an intrinsic high Qf value of 126,390 GHz, indicating great potential of improvement of Qf value via further suppressing the extrinsic dielectric losses. These findings establish Li_(1+x)YF_(4+x) ceramics as promising low-ε_r, low-loss candidates for high-frequency microwave and millimeter-wave communication components.

关键词： Collision-induced absorption   Carbon dioxide   H2   Atmospheric composition   Binary absorption coefficients  

摘要： The collision-induced absorption (CIA) of a H2-CO2 mixture has been studied in the [3907, 4770] cm-1 spectral range for temperatures ranging from 241 to 498 K. The experiments were based on the use of a new high-resolution Fourier spectrometer coupled with an atmospheric simulation chamber. Binary absorption coefficients (BACs) were measured for the first time in the [4033, 4730] cm-1 spectral range at temperatures other than room temperature and are provided in tabular form. At room temperature, the results are compared with existing experimental data and theoretical coefficients, while for the other temperatures, only theoretical values are available. For all considered temperatures, we computed the theoretical integrated band intensity for the experimental BACs and the semi-empirical models. The calculations have been made over the reduced [4033, 4730] cm-1 spectral range, and the entire band, in order to explore the bias induced by using a restricted spectral region. Furthermore, the H2-CO2 BACs were compared with the previously measured H2-H2 and H2-He data. We observed an overall higher absorption of the H2-CO2 BACs, with scaling factors ranging from six to sixteen with respect to the H2-H2 BACs, and from nine to twenty-seven for the H2-He case, depending on the spectral region. Finally, we used an empirical approach, to parametrize the BACs using an exponential profile as a function of temperature, using a series of wavenumber-dependent coefficients, an. These coefficients allow to interpolate the BACs in the temperature range covered by the measurements.

关键词： Myopia   Scleral remodeling   Hypoxia   Glycolysis   Lactate   Autophagy  

摘要：

• •
  Hypoxia drives HIF-1α-dependent glycolytic rewiring in scleral fibroblasts.
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  CQ flux assays support enhanced autophagic flux under hypoxia and lactate.
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  PH controls separate lactate-associated effects from extracellular acidification.
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  GNE-140 add-back supports a downstream LDH/lactate branch in remodeling.
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  Subconjunctival 2DG lowers scleral lactate and attenuates FDM progression.

关键词： Almost affinely disjoint subspace   Asymptotically optimal families   Block matrices   Determinant   Partial spread  

摘要： Let ${\mathbb{F}}_q$ denote the finite field of size q and ${\mathbb{F}}_q^n$ denote the standard vector space over ${\mathbb{F}}_q$. A collection of k-dimensional subspaces of ${\mathbb{F}}_q^n$ with pairwise trivial intersection is called a partial k-spread. A partial k-spread is called an almost affinely disjoint (AAD) subspace family if each affine coset of a member of this family intersects at most L subspaces in the family. In particular, if $n=2k+1$, the family is called L-nice.

关键词： Rare-earth orthochromite   Perovskite A-site substitution   Vibrational property   Magnetic property   Optical bandgap  

摘要： The (Nd_1-xSm_x)CrO₃ (0 ≤ x ≤ 1) solid solution was synthesized by conventional solid-state reactions. X-ray powder diffraction data Rietveld refinements confirm that each compound could be described in the orthorhombic space group Pnma. Successive replacement of Nd³⁺ by smaller Sm³⁺ cations induces an anisotropic lattice response, characterized by contraction of the b- and c-lattice parameters with a slight expansion in the a-direction, resulting in an overall linear decrease of the unit cell volume. Structure analysis reveals that lattice accommodation occurs predominantly through octahedral tilting and oxygen displacement rather than a significant compression of the Cr–O bond. This effect is evidenced by the nearly invariant CrO₆ octahedral volume and quadratic elongation across the solid solution. The CrO₆ octahedra exhibit higher tilting for the Sm-rich compositions, highlighting how the perovskite-type A-site substitution reduces the tolerance factor. Temperature-dependent magnetization reveals long-range antiferromagnetic ordering of the Cr³⁺ sublattice. The magnetic response of the intermediate compositions (0 < x < 1) exhibits two distinct anomalies near the closely spaced Néel temperatures of the endmembers. The negative Curie-Weiss temperatures obtained from the paramagnetic regime further support the dominant antiferromagnetic interactions. The absolute values of the Curie–Weiss temperatures increase with increasing Sm content, consistent with systematic changes in the Cr–O–Cr superexchange pathway caused by enhanced octahedral tilting. The spin reorientation transition observed for the Nd-rich compositions is gradually suppressed with increasing Sm substitution. In the same way, Raman as well as FTIR spectroscopic data demonstrate systematic hardening of the optical

关键词： Anticancer   Docking   EGFR   Oxadiazole   Thiadiazine   Triazole  

摘要： A novel series of heterocyclic compounds was developed, synthesized, and assessed for their in vitro anticancer efficacy and EGFR inhibitory activities. The cytotoxicity of the synthesized compounds was evaluated against A-549 and NCI-H460 lung cancer cell lines, as well as normal HEK-293 cells, using erlotinib and doxorubicin as reference standards. Multiple compounds had considerable anticancer efficacy, with 8f and 8g identified as the most effective possibilities, with IC₅₀ values ranging from 2.53 to 6.51 μM, surpassing erlotinib. These compounds exhibited significant EGFR inhibition, with 8f (IC₅₀ = 0.26 μM) and 8g (IC₅₀ = 0.36 μM) surpassing the standard drug. Molecular docking analyses of the EGFR kinase domain demonstrated advantageous binding affinities and significant interactions with the hinge region residue MET769, corroborated by many hydrogen bonds and substantial π-interactions. A strong association between docking scores and biological activity was noted, validating EGFR as a potential molecular target. The findings designate 8f and 8g as prospective lead compounds for further development as EGFR-targeted anticancer therapies.

关键词： S−C coupling   Glycosyl 1-thioacetate   Aryl-iodide   Pd-catalyst recycling   Thioglucoside analogues of gliflozins  

摘要： In this study, we developed a green method for direct S−C cross-coupling between glycosyl 1-thioacetates and aryl iodides under mild conditions, affording S−C cross-coupling products in excellent yields. The cross-coupling reactions typically proceeded at 50 °C in DMF for 2–6 h, catalyzed by 2–8 mol% of PdG₃-XantPhos with K₂CO₃ as a base. We further demonstrated that the expensive Pd-catalyst and unreacted raw materials could be conveniently recycled through simple extraction and crystallization operations. The method was subsequently applied to the efficient synthesis of thioglucoside analogues of gliflozins, which are promising SGLT2 inhibitors with potential applications as antidiabetic drugs.

关键词： 1-methylnaphthalene (1-MN)   Hydrocracking   BTX   Composite catalysts   Graded catalysts  

摘要： Hydrocracking of polycyclic aromatic hydrocarbons (PAHs) to produce benzene, toluene, and xylene (BTX) represents an effective route for upgrading light cycle oil (LCO). However, this process tends to generate large amounts of alkylbenzenes with long or multiple side chains, making it difficult for a single catalyst to achieve a high BTX selectivity. Herein, composite zeolite catalysts and graded catalyst systems were designed and prepared for the hydrocracking of 1-methylnaphthalene (1-MN) to BTX at a temperature of 420 °C and a pressure of 6 MPa. The NiW/BY-20 catalyst (Beta-USY zeolite composite) promotes the ring-opening cracking of monocyclic aromatics and the side-chain cleavage of alkylbenzenes, increasing the BTX selectivity and yield to 37.4% and 36.4%, respectively. The NiW/BZ-20 catalyst (Beta-ZSM-5 zeolite composite), with its strong acidity and high dealkylation capability, further improves the BTX selectivity and yield to 38.1% and 37.3%, respectively. These results indicate that composite zeolite catalysts can synergistically integrate the catalytic properties of zeolites with distinct topologies, enabling a relay catalysis pathway. Further investigations reveal that the graded catalyst system optimizes the reaction process; the B-Y catalyst (NiW/Beta in the upper bed, NiW/USY in the lower bed) increases the BTX selectivity and yield to 38.5% and 38.3%, respectively. The optimized B-Y-Z three-bed graded catalyst (upper: NiW/Beta, middle: NiW/USY, and lower: NiW/ZSM-5) exhibits excellent compatibility with the reaction pathway for 1-MN hydrocracking to BTX. It enhances the tandem catalytic effect while maintaining high hydrocracking activity, achieving BTX selectivity and yield of 41.3% and 40.2%, respectively, with alkylbenzene selectivity reduced by 3.3%. This work demonstrates that the synergistic design of composite zeolites and graded catalysts can effectively boost the efficient and targeted conversion of PAHs to BTX, providing valuable insights

关键词： Alzheimer’s disease   apoptosis   mitochondria   neuroinflammation   oxidative stress   Parkinson’s disease   voltage-dependent anion channel 1  

摘要： Voltage-dependent anion channel 1 is an integral outer membrane protein of the mitochondria that governs apoptosis,enables metabolite exchange,and influences mitochondrial activity.In neurodegenerative diseases,such as amyotrophic lateral sclerosis,Parkinson's disease,Huntington's disease,and Alzheimer's disease,oxidative stress,neuroinflammation,and mitochondrial dysfunction are frequent features.Voltage-dependent anion channel 1 is a key regulator of these processes.This review described the structure,membrane topology,and physiological function of voltage-dependent anion channel 1 in neurons and glial cells.We emphasize how it affects mitophagy,oxidative damage,and changes in mitochondrial permeability.Special attention is focused on how voltagedependent anion channel 1 interacts with pathogenic proteins that damage mitochondrial integrity and cause neurotoxicity,including mutant huntingtin,phosphorylated tau,α-synuclein,amyloid-beta,and TAR DNA-binding protein 43.Furthermore,the paper examines the function of voltage-dependent anion channel 1 in astrocytic dysfunction and microglial activation,highlighting its impact on neuroinflammation.In a nutshell,we assess treatment strategies that target voltage-dependent anion channel 1,such as VBIT-4,a selective inhibitor of voltagedependent anion channel 1 oligomerization,and newer methods,including structure-based drug design and CRISPR/Cas9 regulation.Improved knowledge of the hinter voltage-dependent anion channel 1 of the molecular mechanism may allow for new therapeutic approaches in neurodegenerative diseases.