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关键词： Bifunctional catalyst   Core–shell structure   Hydroformylation   Magnetic nanoparticles   One-step alcohol synthesis  

摘要： The purpose of the olefin hydroformylation-hydrogenation tandem reaction for alcohol synthesis is to design a highly efficient and stable heterogeneous catalyst. In this study, a novel heterogeneous magnetic nanoparticle-supported rhodium-cobalt bimetallic core–shell catalyst was prepared, which exhibits excellent synergistic catalytic performance and enables a one-step alcohol synthesis process. The magnetic support Fe₃O₄ allows for rapid separation of the catalyst from reaction products under an external magnetic field. The 7.5Co0.5Rh/Fe₃O₄@SiO₂ magnetic core–shell catalyst was successfully prepared by loading active metals via a one-pot impregnation method and performing silica coating using the Stöber method. It shows outstanding olefin conversion (99.71%) and alcohol selectivity (91.17%). The effect of preparation conditions, process conditions, and the universality of substrates were investigated in detail. The catalyst was reused 5 times, and the performance differences between the core–shell catalyst and the traditional impregnated catalyst with the same support, as well as the differences in metal leaching during the reaction, were compared. In addition, the catalyst could participate in the reaction directly without prior reduction, avoiding the additional costs associated with subsequent reduction steps.

关键词： large for gestational age   pregestational type1 diabetes mellitus   glycaemic control  

摘要： Objectives: Large for gestational age (LGA) is defined as a birth weight equal to or higher than the 90th centile for a certain gestational age. Despite the efforts to optimize therapeutic goals to stabilize diabetes, there is still a high rate of LGA in type 1 diabetes mellitus (T1DM) mothers. The aim of this paper is a literature review of the data on predictors of LGA incidence in pregnancies complicated by type 1 diabetes mellitus. Results: Potential LGA predictors in pregestational diabetes include glucose concentration during pregnancy, maternal age, diabetes duration, increased body weight both at the beginning of gestation and at the time of delivery, as well as the weight gain in pregnancy. LGA risk is also associated with the use of an insulin pump (CSII), especially without the support of a continuous glucose monitoring system (CGMS). Significant glycaemic control parameters among others include average fasting glycaemia in the 3rd trimester, HbA1c in the 1st and 3rd trimesters, and among CGMS parameters - shorter TIR (time in range), shorterTBR (time below range) in the 2nd and 3rd trimesters, longerTAR (time above range) > 140 and average glycaemia in each trimester of gestation. Conclusions: There is still a need for identification of new predictors and theraputic goals in pregnancy inT1DM women to reduce the prevalence of LGA newborns.

关键词： Low-density lipoprotein cholesterol   Lipid management   Health checkup   Cardiovascular risk   Lifestyle factors  

摘要： Aims: Despite strong recommendations for medical consultation, the treatment status and low-density lipoprotein cholesterol (LDL-C) levels at 1-year follow-up of individuals with referral-level LDL-C identified in health checkups remain unclear. We evaluated the treatment status and 1-year LDL-C control among individuals identified in health checkups as requiring early medical consultation due to LDL-C levels of >_ 180 mg/dL. Methods: We conducted a nationwide cohort study including health checkup data for individuals aged 20-74 years. We identified 102,049 individuals (median age: 48 years;male: 66.8%) with uncontrolled LDL-C (>_ 180 mg/dL) at baseline, who had no prior lipid-lowering therapy. Poisson regression with robust error variance was used to assess factors associated with uncontrolled LDL-C at 1 year. Results: Among individuals with LDL-C >_ 180 mg/dL at baseline, 56,147 (55.0%) visited a medical institution within 3 months of the checkup, and 13,124 (12.9%) were prescribed lipid-lowering medications at 1 year. At 1 year follow-up, 49,260 (48.3%) still had LDL-C >_ 180 mg/dL. Factors associated with persistent LDL-C >_ 180 mg/dL at 1 year included obesity (RR: 1.07, [95% CI: 1.06-1.09]), 10 mg/dL increase in LDL-C at baseline (1.11 [1.10-1.11]), smoking (1.05 [1.04-1.07]), alcohol consumption (0.95 [0.94-0.97]), poor sleep quality (1.02 [1.01-1.03]), and skipping breakfast >_ 3 times per week (1.07 [1.05-1.08]). Conclusions: Despite being classified as requiring early medical intervention, only half of individuals with LDL-C >_ 180 mg/dL visited a physician within 3 months, and nearly half continued to have uncontrolled LDL-C at 1 year. Strategies to facilitate timely medical visits and appropriate lipid management in health checkupidentified cases are warranted.

关键词： Noise   SQUIDs   Time division multiplexing   1/f noise   Frequency modulation   Multiplexing   Noise reduction   NASA   Low frequency noise   Frequency division multiplexing   Imaging array   multiplexed readout   superconducting device   transition-edge sensor   X-ray spectroscopy  

摘要： We present a novel noise modulation technique using superconducting quantum interference device (SQUID) gain switching for time division multiplexing (TDM) readout systems that reduces 1/f noise by a factor of 3.5 while preserving the architectural simplicity that makes TDM a widely used technique for transition edge sensor (TES) arrays. In contrast to frequency division multiplexing or microwave multiplexing, where signal modulation inherently provides immunity to low-frequency noise, conventional TDM systems can be susceptible to 1/f noise from downstream electronics as the TES signals remain in the low-frequency band. In our approach, the operating point of the SQUID amplifier alternates between positive and negative gain slopes at the frame frequency, combined with synchronized digital inversion of the error signals prior to flux-locked loop integration. This modulation scheme shifts the readout noise, including the 1/f components of low noise amplifiers, analog-to-digital converters and room temperature electronics, into the frame frequency range where it can be separated from the DC-TES signal by decimation filtering. Laboratory validation using an 8 column x32 row TDM platform designed for Athena X-IFU applications shows a reduction in 1/f noise from 73 pA/root Hz@1 Hz (9.3 mu Phi(0)/root Hz) to 21 pA/root Hz@1 Hz (2.7 mu Phi(0)/root Hz) in channels with no TES connected, with the additional benefits of a 14-fold reduction in SQUID bias sensitivity through dynamic resistance matching and a 6.5-fold reduction in temperature-induced baseline drift. The technique avoids the disadvantage of doubling white noise, which occurs with conventional noise subtraction methods, and at the same time achieves a comparable suppression of 1/f noise. Implementation requires only minor firmware modifications to existing TDM systems, making it easily implementable for far-infrared bolometric and X-ray spectroscopy applications.

关键词： PET upcycling   Piezo-photocatalytic reforming   Defect engineering   Sustainable chemistry   Reaction pathway  

摘要： Piezo-photocatalytic upcycling of plastic waste into added-value hydrocarbon fuel leverages mechanical and solar energy to reintegrate end-of-life plastics into the carbon cycle. This work reports a process that converts PET-derived ethylene glycol (EG) into syngas under ambient conditions using defect-engineered Ba_xSr_1−xTiO_3−y (BSTO) catalysts. A three-stage process produces graded oxygen-vacancy and Ti^3 + surface concentrations. Combination with optimized band structure yields catalysts of strong piezo-photo responses. Photoelectrochemical measurements confirm accelerated light-induced charge separation and transfer, while Kelvin probe force microscopy and DFT simulations corroborate defect-amplified piezoelectric polarization. Using this catalyst, EG solutions derived from PET microplastics and textile fibers demonstrate selective syngas compositions, confirming applicability to real-world PET waste. Mechanistic studies show that piezo-photo-reforming of EG achieves respective H₂ and CO evolution rates of 1062 and 646 μmol/g/h, > 90% syngas selectivity, and an H₂/CO ratio (∼1.6), representing nearly a 20-fold increase in gas yield over photocatalysis alone. Control experiments demonstrate that catalyst composition and activation govern both catalytic activity and syngas ratio tunability. In situ ATR-FTIR identifies surface formate as a key intermediate, while ¹H NMR detects glycolic acid/glycolate in the liquid phase. DFT calculations indicate that lattice-oxygen-assisted C–C bond cleavage is significantly promoted within the reaction pathways.

关键词： 1   4-Butanediol oxidation reaction   Electrocatalysis   Lattice distortion   Paired-electrosynthesis   PBS upcycling  

摘要： The widespread use of polybutylene succinate (PBS) plastic poses a high pollution risk due to its protracted degradation under natural environments, while the electrocatalytic PBS waste upcycling offers a promising approach. This study develops a self-supported Mn-doped nickel-based layered double hydroxide (NiMn-LDH) catalyst with nanoribbon arrays for the electrocatalytic oxidation of PBS-derived 1,4-butanediol (BDO) to succinic acid (SA). Structural characterization and theoretical calculations reveal that the Mn doping induces lattice distortion and e_g* band broadening of the active NiOOH phase, elevating the d-band center to enhance intermediate adsorption and electron transfer, while the enriched oxygen vacancies promote OH⁻ enrichment. These results synergistically improve the intrinsic electrocatalytic activity of NiMn-LDH/NF toward the anodic BDO oxidation reaction (BOR). By virtue of these structural merits, this catalyst displays an extraordinary electrocatalytic performance for BOR, yielding 95.1% SA at 1.5 V vs. RHE with 93.7% Faradaic efficiency. Furthermore, a membrane-free paired-electrosynthesis system coupling anodic BOR with cathodic maleic acid hydrogenation reaction (MHR) enables energy-saving co-production of SA at both electrodes with 156.7% apparent Faradaic efficiency, yielding 36.02 g of high-purity SA. This work elucidates the critical role of lattice distortion modulation of electrocatalysts in enhancing catalytic activity and offers insights for designing sustainable electrocatalytic upcycling systems.

关键词： Dirac equation   Dirac semimetals   Finite-differences   Numerical scheme   Runge-Kutta methods   Symplectic integrator   Tilted Dirac cones  

摘要： Owing to their increased electron mobility compared to conventional semiconductors, three-dimensional (3D) Dirac semimetals are considered to be promising candidates for integration into next-generation electronic devices. In these materials, the low-energy dynamics of the charge carriers are governed by an effective tilted Dirac equation, in which a mass term appears when strain is applied to the crystal lattice. In this work, we present a novel finite-difference scheme capable of numerically solving the 3D tilted Dirac equation in the time domain. The method employs fourth-order accurate finite differences to discretize the spatial derivatives and a symplectic partitioned Runge-Kutta (PRK) integrator to propagate the Dirac spinor in time. To this end, a careful separation of the complex-valued spinor into two real-valued parts is performed to ensure compatibility with the PRK technique. Moreover, to account for the additional term in the Hamiltonian arising from the tilt of the Dirac cones, fourth-order accurate averaging operators are incorporated into the spatial discretization, without compromising the key properties of the scheme. The resulting numerical method is explicit and is shown to conserve the norm, energy, and momentum of the system. Its stability condition is derived, and the numerical dispersion is thoroughly investigated. Illustrative numerical experiments are performed, demonstrating the excellent properties of the proposed method and its applicability to a more realistic scenario in which retroreflection is predicted to occur in the Dirac semimetal Cd₃As₂, as a result of its tilted dispersion relation.

关键词： 5 G dielectric resonator antenna   High-entropy design   Microwave dielectric ceramics   Olivine structure   Ultra-low dielectric loss  

摘要： Next-generation wireless communication demands microwave dielectric ceramics that effectively achieve ultra-low loss, a stable resonant frequency, and a low permittivity. Here we demonstrate an entropy-engineering strategy that selectively disorders the [A(2)O₆] octahedral site while preserving the rigid [GaO₄] tetrahedral backbone in gallium-based olivine A₂GaO₄. A series of CaY_1–x(Nd_0.25Sm_0.25Eu_0.25Yb_0.25)_xGaO₄ ceramics was synthesized by solid-state reaction at 1260–1420 °C. Systematic increases in configurational entropy (ΔS_config) and ionic-size disorder (δ_R) drive a reversible Pnma → Pmnb symmetry switch, suppress phase separation, and expand the lattice. At x = 0.8, the high-entropy single-phase olivine exhibits ε_r = 9.2 ± 0.2, Q×f = 151,025 ± 400 GHz, and τ_f = -39.8 ± 2.0 ppm/°C, while Vickers hardness rises to 5.79 ± 0.2 GPa. Ultra-low loss is synergistically influenced by ΔS_config, δ_R, and packing fraction. A C-band dielectric resonator antenna fabricated from the x = 0.8 composition achieves 92.63 % radiation efficiency and 6.39 dBi gain, validating the entropy-design paradigm for high-frequency applications.