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关键词： Metal-organic framework   Christian-Albrechts-University-1 (CAU-1)   polymethyl methacrylate (PMMA)   Hydrogen-selective separation   Thin-film nanocomposite  

摘要： The amine-functionalized Christian-Albrechts-University-1 (CAU-1) metal–organic framework (MOF) possesses intrinsic structural features ideally suited for hydrogen (H₂) separation, with pore apertures closely matching the molecular size of hydrogen, thereby enabling selective hydrogen transport via molecular sieving. The physico-chemical and structural tailoring of CAU-1 holds immense potential for gas separation thin-film nanocomposite (TFN) membranes yet it remains largely unexplored. This work presents the first systematic investigation of CAU-1 incorporation confined within a thin PMMA selective layer supported on a polysulfone (PSF) substrate, elucidating its influence on the interfacial structure, gas transport pathways, and hydrogen separation performance of polymethyl methacrylate (PMMA)/CAU-1 TFN membranes. Morphological analyses revealed the successful formation of thin, dense, and defect-free TFN exhibiting excellent polymer-filler compatibility with no observable interfacial voids, while thermogravimetric analysis demonstrated excellent thermal stability up to 360 °C. The optimized PMMA/CAU0.5 membrane achieved an H₂ permeability of 294.43 Barrer, with ideal selectivities of 4.91, 6.30 and 5.03 against carbon dioxide (CO₂), nitrogen (N₂), and methane (CH₄), respectively, representing respective improvements of 11%, 42%, and 51% over pristine PMMA. Under mixed-gas conditions, the H₂/CO₂ separation factor surpassed the Robeson upper limit indicating the effective H₂-selective transport properties. These findings highlight the pivotal role of CAU-1 in creating microporous, H₂-selective transport pathways, demonstrating the potential of PMMA/CAU-1 TFN membranes for enhanced hydrogen purification.

关键词： DJ-1 protein   Qinchuan beef   PI3K/Akt signaling pathway   Mitochondrial apoptosis   Compound-23  

摘要： This study explores the role of the nucleic acid deglycase DJ-1 protein in regulating mitochondrial apoptosis during post-slaughter storage of Qinchuan beef via the phosphatidylinositol-3-kinase (PI3K)/protein kinase B (Akt) signaling pathway. The study evaluates the expression of key proteins in the PI3K/Akt pathway, apoptotic proteins, DJ-1 protein, as well as markers of oxidative stress, mitochondrial damage, and apoptosis. Our results indicate that prolonged post-slaughter storage suppressed the DJ-1-mediated PI3K/Akt signaling pathway, which regulates the expression of downstream proteins. This cascade leads to mitochondrial damage and ultimately induces apoptosis. In contrast, treatment with the DJ-1 stabilizer compound-23 modulates mitochondrial function through the PI3K/Akt pathway. This intervention reduces reactive oxygen species levels, inhibits the opening of the mitochondrial permeability transition pore, attenuates the loss of mitochondrial membrane potential, lowers caspase-3 activity, and decreases the B-cell lymphoma 2 (Bcl-2)-associated X protein (Bax)/Bcl-2 ratio, thereby effectively suppressing mitochondrial apoptosis. These findings establish a solid foundation for understanding the role of the DJ-1 protein and PI3K/Akt signaling pathway in post-slaughter myocytes.

关键词： primary   11A07   11A41   11A63   11K36   11L07   11L20   secondary   11B50   11L03   11N13   Exponential sums   Prime numbers   Uniform distribution modulo 1   Sum of digits function  

摘要： We study sets $\mathcal{N}$ of the prime numbers defined by combinations of arithmetic constraints. For a fixed real number α, we investigate the uniform distribution modulo one of the sequence ${(\alpha p)}_{p\in \mathcal{N}}$.

关键词： 17B10   17B65   17B68   N=1 Heisenberg-Virasoro superalgebra   Non-weight module   Irreducible quotient module  

摘要： We first define a class of non-weight modules over the N=1 Heisenberg-Virasoro superalgebra $\mathfrak{g}$, which are reducible modules. Then we give all submodules of such modules, and present the corresponding irreducible quotient modules which were exactly studied in [7]. Also, we prove that those modules constitute a complete classification of $U(\mathfrak{h})$-free modules of rank 2 over $\mathfrak{g}$, where $\mathfrak{h}=\mathbb{C}{L}_0\oplus \mathbb{C}{H}_0$ is a degree-0 subalgebra of $\mathfrak{g}$. As an application, we obtain a class of weight $\mathfrak{g}$-modules from those non-weight $\mathfrak{g}$-modules by the weighting functor. Furthermore, we study the non-weight modules over the four subalgebras of $\mathfrak{g}$: (i) the Heisenberg-Vir

关键词： Coalbedgas   Separation   1,3-Diox   Hydrate particles   Methane recovery  

摘要： Recovering CH₄ from low-concentration coalbed gas (LCBG) is of critical importance for addressing energy shortages and reducing greenhouse gas emissions. However, the formation of hydrates in solution is frequently limited by mass transfer constraints, resulting in reduced separation efficiency. This study proposes an advanced LCBG separation method that employs loose 1,3-dioxlane (1,3-Diox) hydrate particles as the medium. It comprehensively examines the effects of various kinetic hydrate promoters, operating temperature, initial pressure, and 1,3-Diox hydrate particle size on separation performance. The results show that hydrate particles formed from a solution containing 5.56 mol% 1,3-Diox and 5000 ppm L-tryptophan (L-Trp) achieve optimal separation performance for LCBG. Under conditions of 3.0 MPa and 269.65 K, the CH₄ concentration in the residual gas phase decreased from 30.09 mol% to 15.20 mol%, achieving a CH₄ recovery rate of 78.70% and a separation factor of 3.84. Raman spectroscopy analysis confirms that CH₄ molecules effectively occupy the unsaturated small cages within 1,3-Diox primary hydrate particles after separation, while N₂ molecules compete with CH₄ for occupancy in the small cages. Moreover, the findings indicate that the CH₄ recovery rate initially increases and then decreases with decreasing temperature. While increasing the initial pressure accelerates the reaction rate, it slightly diminishes the CH₄ recovery rate. Additionally, smaller 1,3-Diox hydrate particle sizes enhance both the reaction rate and the CH₄ recovery rate. This study offers significant theoretical insights and practical guidance for the application of hydrate separation technology in recovering CH₄ from coalbed gas.

关键词： HEFA-SAF   Jet A-1   NexGen burner   Gaseous emissions   Emission index   Equivalence ratio   GC-MS fuel composition  

摘要： In recent years, the civil aviation industry has encountered growing pressure from the public and regulators to curb air pollutants and climate emissions. Sustainable aviation fuels (SAFs) produced through the Hydroprocessed Esters and Fatty Acids (HEFA) method have been approved as blends with conventional Jet A-1 under ASTM D7566. However, comparative burner-scale evidence linking composition, gaseous emissions, and emission indices (EI) across lean to rich combustion remains limited, particularly for HEFA-rich blends and SO2 behaviour. This study employs the FAA-certified Next Generation (NexGen) burner-for the first time applied to HEFA-SAF and HEFA-rich blends to measure O2, CO2, CO, NOx and SO2 for Jet A-1 (B0 HEFA-SAF (B100) and their blends (B50J50, B70J30, B90J10) across twelve equivalence ratios (phi = 0.50-1.44 compute fuelnormalised EI-CO, EI-CO2, EI-NOx and EI-SO2, none of which have been reported from this platform for SAF or blends and pair emissions with GC-MS end-member fingerprints. NexGen burner provides a realistic fire conditions, like those encountered in real-life accidents, particularly in areas near aircraft engines. HEFA blending improved key properties (lower density and viscosity, lower freezing point, higher flash point and gravimetric energy density). B100 showed the highest residual O2 and the lowest CO, NOx and SO2;EI-CO peaked at 0.811 g/kg fuel (B0) but plunged to 0.010 g/kg fuel for B100, while EI-NOx decreased from 0.198 g/kg fuel (B0) to 0.014 g/kg fuel for B100. HEFA-rich blends EI-CO decreased and their EI-CO2 increased. However, EI-NOx increased non-linearly with HEFA fraction under lean-to-stoichiometric conditions (phi = 0.50-1.0). Attributed to the higher gravimetric energy density of HEFA-rich blends increasing local flame temperature and amplifying the thermal Zeldovich NOx pathway;an equivalence-ratio-dependent trade-off that reverses at rich conditions where B100 retains its 80.1% NOx advantage over B0. Non-monotonic EI

关键词： Three-way catalysts   LaNi1-xCoxO3 perovskite   Automotive exhaust gas   CO oxidation   C3H6 oxidation  

摘要： LaNi_1-xCo_xO₃ (x = 0, 0.3, 0.5) perovskite-type oxides were synthesized and evaluated as three-way catalysts (TWCs) for the simultaneous removal of CO, C₃H₆, and NO from automotive exhaust. TPR results revealed a progressive decrease in reduction temperatures upon cobalt incorporation, attributed to enhanced hydrogen spillover and improved oxygen mobility. FESEM and BET analyses showed pseudo-spherical morphologies with increased macroporosity but reduced surface areas and particle aggregation upon cobalt doping. XPS demonstrated enrichment of chemisorbed oxygen (O_ad) and higher Ni³⁺/Ni²⁺ ratios with increasing cobalt content, correlating with enhanced redox properties. Optical characterization revealed band-gap narrowing from 2.40 eV (LaNiO₃) to 2.31 eV (LaNi_0.5Co_0.5O₃), favoring electron transfer. Catalytic activity tests demonstrated significant improvements in CO and C₃H₆ oxidation after cobalt substitution, with T₅₀ for CO oxidation decreasing from 185 °C (LaNiO₃) to 164.6 °C (LaNi_0.5Co_0.5O₃), and T₉₀ from 228.1 °C (LaNiO₃) to 207.5 °C (LaNi_0.5Co_0.5O₃). Similarly, T₅₀ for C₃H₆ conversion reached 266.8 °C and T₉₀ at 312.1 °C for LaNi_0.5Co_0.5O₃, compared to 307.1 °C and 335.0 °C for pristine LaNiO₃. Although NO conversion peaked at ∼90% around 275 °C for LaNiO₃, it decreased upon Co substitution due to equilibrium constraints. These findings demonstrate that cobalt incorporation enhances reducibility, lattice oxygen mobility, and surface oxygen reactivity, thereby promoting CO and hydrocarbon oxidation under TWC conditions.

关键词： Julolidine-1-one   N-substituted Tetrahydroquinoline   Organic fluorophores   UV–Vis   Fluorescence spectroscopy   TD-DFT  

摘要：

• •
  New julolidine-1-one derivatives were synthesized and spectroscopically characterized.
• •
  Experimental UV–Vis/fluorescence data correlated with TD-DFT calculationsreveal clear structure–photophysical relationships.
• •
  Fluorescence properties reveal sensitivity to structural modifications influencing intramolecular charge transfer.

关键词： Glycerol   1,3-propanediol   Pt-WOx interaction   Oxygen vacancy   TetrahedralW5  

摘要： Pt/WO_x/Al₂O₃ catalysts with tunable oxygen-vacancy concentrations were prepared by sequential impregnation using Al₂O₃ supports calcined at different temperatures. Glycerol hydrogenolysis to 1,3-propanediol showed a volcano-type dependence on support calcination temperature, and Pt/WO_x/Al₂O₃-600 gave the highest 1,3-PDO yield, nearly twice that of the untreated catalyst. The superior performance of Pt/WO_x/Al₂O₃-600 is primarily attributed to the formation of abundant oxygen vacancies on the Al₂O₃ support at the optimal calcination temperature. Quantitative correlation analysis indicates that oxygen vacancies are far more closely associated with tungsten dispersion, serving as the primary anchoring sites, whereas Al³⁺_penta likely plays a secondary of stabilizing role. At excessively high calcination temperatures, sintering decreases the vacancy concentration and damages the interfacial structure, leading to lower activity. These results demonstrate that support defect engineering is an effective strategy for regulating metal-support interactions and constructing efficient bifunctional catalysts for selective C-O bond cleavage.

摘要： In recent years, the civil aviation industry has encountered growing pressure from the public and regulators to curb air pollutants and climate emissions. Sustainable aviation fuels (SAFs) produced through the Hydroprocessed Esters and Fatty Acids (HEFA) method have been approved as blends with conventional Jet A-1 under ASTM D7566. However, comparative burner-scale evidence linking composition, gaseous emissions, and emission indices (EI) across lean to rich combustion remains limited, particularly for HEFA-rich blends and SO₂ behaviour. This study employs the FAA-certified Next Generation (NexGen) burner-for the first time applied to HEFA-SAF and HEFA-rich blends to measure O₂, CO₂, CO, NOx and SO₂ for Jet A-1 (B0), HEFA-SAF (B100) and their blends (B50J50, B70J30, B90J10) across twelve equivalence ratios (ϕ = 0.50–1.44), compute fuel-normalised EI-CO, EI-CO₂, EI-NOx and EI-SO₂, none of which have been reported from this platform for SAF or blends and pair emissions with GC–MS end-member fingerprints. NexGen burner provides a realistic fire conditions, like those encountered in real-life accidents, particularly in areas near aircraft engines. HEFA blending improved key properties (lower density and viscosity, lower freezing point, higher flash point and gravimetric energy density). B100 showed the highest residual O₂ and the lowest CO, NOx and SO₂; EI-CO peaked at 0.811 g/kg fuel (B0) but plunged to 0.010 g/kg fuel for B100, while EI-NOx decreased from 0.198