Radiation-Synthesized Metal-Organic Frameworks with Ligand-Induced Lewis Pairs for Selective CO2 Electroreduction.

The electrochemical activation of inert CO2 molecules through C─C coupling reactions under ambient conditions remains a significant challenge but holds great promise for sustainable development and the reduction of CO2 emission. Lewis pairs can capture and react with CO2, offering a novel strategy for the electrosynthesis of high-value-added C2 products. Herein, an electron-beam irradiation strategy is presented for rapidly synthesizing a metal-organic framework (MOF) with well-defined Lewis pairs (i.e., Cu- Npyridinic). The synthesized MOFs exhibit a total C2 product faradic efficiency of 70.0% at -0.88 V versus RHE. In situ attenuated total reflection Fourier transform infrared and Raman spectra reveal that the electron-deficient Lewis acidic Cu sites and electron-rich Lewis basic pyridinic N sites in the ligand facilitate the targeted chemisorption, activation, and conversion of CO2 molecules. DFT calculations further elucidate the electronic interactions of key intermediates in the CO2 reduction reaction. The work not only advances Lewis pair-site MOFs as a new platform for CO2 electrochemical conversion, but also provides pioneering insights into the underlying mechanisms of electron-beam irradiated synthesis of advanced nanomaterials.

Solvent Effects on Spin-Orbit Charge-Transfer Intersystem Crossing in Aryl-Substituted Boron-dipyrromethene Donor-Acceptor Dyads.

In heavy-atom-free organic molecules, the rate of triplet generation through charge recombination, as dictated by the El-Sayed rule, can be enhanced by 101-102 times compared with the rate of spontaneous spin flipping between π-π* orbitals. This mechanism is known as the spin-orbit charge-transfer intersystem crossing (SOCT-ISC). Within the framework of the SOCT-ISC mechanism, facilitating the generation of charge-separated (CS) states and suppressing the spin-allowed direct charge recombination to the ground state are pivotal for maximizing the efficiency of generating localized triplet states. Herein, a series of orthogonal aryl-substituted boron-dipyrromethene dyads were studied by time-resolved spectroscopy to unravel the multichannel competitive relationships in the SOCT-ISC mechanism. The energy level of the electron donor and the stabilization of the solvent effect to the charge-transfer state are reflected in the Gibbs free energy changes of the electron transfer and recombination reactions, leading to significantly different triplet quantum yields. Additionally, solvation-induced electronic coupling changes in excited states lead to the fact that the spin-allowed charge recombination rate cannot be well simply predicted by the Marcus inverted region but has to consider the specific excited-state dynamics in optimizing the proportion of triplet generation channels based on charge recombination.

Cobalt-Catalyzed Asymmetric Hydrogenation of Ketones Enabled by the Synergism of an N-H Functionality and a Redox-Active Ligand.

The transition metal-catalyzed asymmetric hydrogenation (AH) of ketones to produce enantioenriched alcohols is an important reaction in organic chemistry with applications in the pharmaceutical and agrochemical fields. Using earth-abundant, biorelevant cobalt as the central metal in the catalyst has a high potential to improve sustainability and achieve hydrogenation reactions that are scalable. However, due to the high d-electron count, designing cobalt catalysts that exhibit turnover numbers (TONs, ≥1000) and enantioselectivities (≥90%) sufficient for synthetic utility and practical scalability (≥1 kg scale) remains a challenge. In this work, an efficient catalyst design strategy utilizing an amino(imino)diphosphine Co(II) bromide precatalyst is presented to achieve this goal. The quantitative production of a wide range of secondary chiral alcohols with TONs of up to 150,000 and an enantiomeric excess (e.e.) of up to 99% at a scale of up to 1.35 kg was achieved, indicating that the proposed cobalt catalyst is highly promising for AH and scale-up reactions. A mechanistic study revealed that the synergism of an N-H functionality and a redox-active ligand endows the cobalt catalyst with a high productivity and excellent enantioselectivity.

[Cerebellar ferroptosis of hypertension mice following lead exposure].

OBJECTIVE: Exploring the changes in cerebellar ferroptosis in hypertensive mice after lead exposure. METHODS: Twenty-five healthy C57 male mice were selected to construct a hypertensive model by intraperitoneal injection of angiotensin II(Ang II) at a concentration of 0.05 mg/kg for 7 consecutive days. After a systolic blood pressure of 140 mmHg, 20 hypertensive mice were randomly divided into a hypertensive control group and a hypertensive lead exposure group. Twenty C57 mice with normal blood pressure were randomly divided into a blood pressure normal control group and a blood pressure normal lead exposure group. The mice in the normal blood pressure control group and the hypertensive control group drank water freely. Mice in the lead exposure group with normal blood pressure and the lead exposure group with hypertension drank lead acetate water containing 250 mg/L. Ang II was injected intraperitoneally every two days in the hypertensive control group and hypertensive lead exposed group mice. Each group of mice was poisoned for 12 weeks. Using open field experiments and balance beam experiments to detect motor dysfunction in mice. Using a reagent kit to detect the levels of divalent iron(Fe~(2+)), malondialdehyde(MDA), and glutathione(GSH) in the cerebellum of different groups of mice. Western blot was used to determine the protein expression of member 11 of the solute carrier family 7(SLC7A11), glutathione peroxidase 4(GPX4), nuclear receptor coactivator 4(NCOA4), microtubule associated protein 1 light chain 3B(LC3B), and ferritin heavy chain 1(FTH1) in mouse cerebellar tissue. RESULTS: The result of the open field experiment showed that the activity distance(1013.04 cm) of mice in the hypertensive lead exposure group was significantly lower than that of the hypertensive control group(1351.18 cm) and the lead exposure group with normal blood pressure(1287.35 cm). And the lead exposure group with hypertension also extended the time through the balance beam, which was 29.40 seconds(P<0.05). In addition, the Fe~(2+)content in the cerebellum of mice in the hypertensive lead exposure group was 3.33 µmol/g prot, which was 1.54 times that of the hypertensive control group and 1.14 times that of the lead exposure group with normal blood pressure. The MDA content was 4.71 nmol/mg prot, higher than that of the hypertensive control group and the lead exposure group with normal blood pressure. The GSH content was 5.36 µmol/g prot, lower than that of the hypertensive control group and the lead exposure group with normal blood pressure(P<0.05). Western blot result showed that compared with the hypertensive control group and the lead exposure group with normal blood pressure, the protein expression of SLC7A11 and GPX4 in the hypertensive lead exposure group was significantly reduced(P<0.05). In addition, compared with the control group with normal blood pressure, the expression of NCOA4 and LC3B proteins in the cerebellum of mice in the hypertension control group and lead exposure group with normal blood pressure increased, while the expression of FTH1 protein decreased(P<0.05). The expression of NCOA4 and LC3B proteins in the hypertensive lead exposure group was higher than that in the hypertensive control group and the lead exposure group with normal blood pressure, while the expression of FTH1 protein decreased(P<0.05). CONCLUSION: Lead exposure can exacerbate iron death in the cerebellar tissue of hypertensive mice, and iron autophagy may be involved in its occurrence and development.

Machine learning-guided realization of full-color high-quantum-yield carbon quantum dots.

Carbon quantum dots (CQDs) have versatile applications in luminescence, whereas identifying optimal synthesis conditions has been challenging due to numerous synthesis parameters and multiple desired outcomes, creating an enormous search space. In this study, we present a novel multi-objective optimization strategy utilizing a machine learning (ML) algorithm to intelligently guide the hydrothermal synthesis of CQDs. Our closed-loop approach learns from limited and sparse data, greatly reducing the research cycle and surpassing traditional trial-and-error methods. Moreover, it also reveals the intricate links between synthesis parameters and target properties and unifies the objective function to optimize multiple desired properties like full-color photoluminescence (PL) wavelength and high PL quantum yields (PLQY). With only 63 experiments, we achieve the synthesis of full-color fluorescent CQDs with high PLQY exceeding 60% across all colors. Our study represents a significant advancement in ML-guided CQDs synthesis, setting the stage for developing new materials with multiple desired properties.

Conversion of estriol to estrone: A bacterial strategy for the catabolism of estriol.

Natural estrogens, including estrone (E1), 17ß-estradiol (E2), and estriol (E3), are potentially carcinogenic pollutants commonly found in water and soil environments. Bacterial metabolic pathway of E2 has been studied; however, the catabolic products of E3 have not been discovered thus far. In this study, Novosphingobium sp. ES2-1 was used as the target strain to investigate its catabolic pathway of E3. The metabolites of E3 were identified by high performance liquid chromatography-high resolution mass spectrometry (HPLC-HRMS) combined with stable 13C3-labeling. Strain ES2-1 could almost completely degrade 20 mg∙L-1 of E3 within 72 h under the optimal conditions of 30°C and pH 7.0. When inoculated with strain ES2-1, E3 was initially converted to E1 and then to 4-hydroxyestrone (4-OH-E1), which was then cleaved to HIP (metabolite A6) via the 4, 5-seco pathway or cleaved to the B loop via the 9,10-seco pathway to produce metabolite with a long-chain ketone structure (metabolite B4). Although the ring-opening sequence of the above two metabolic pathways was different, the metabolism of E3 was achieved especially through continuous oxidation reactions. This study reveals that, E3 could be firstly converted to E1 and then to 4-OH-E1, and finally degraded into small molecule metabolites through two alternative pathways, thereby reducing E3 pollution in water and soil environments.

Glycolysis and beyond in glucose metabolism: exploring pulmonary fibrosis at the metabolic crossroads.

At present, pulmonary fibrosis (PF) is a prevalent and irreversible lung disease with limited treatment options, and idiopathic pulmonary fibrosis (IPF) is one of its most common forms. Recent research has highlighted PF as a metabolic-related disease, including dysregulated iron, mitochondria, lipid, and glucose homeostasis. Systematic reports on the regulatory roles of glucose metabolism in PF are rare. This study explores the intricate relationships and signaling pathways between glucose metabolic processes and PF, delving into how key factors involved in glucose metabolism regulate PF progression, and the interplay between them. Specifically, we examined various enzymes, such as hexokinase (HK), 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3), pyruvate kinase (PK), and lactate dehydrogenase (LDH), illustrating their regulatory roles in PF. It highlights the significance of lactate, alongside the role of pyruvate dehydrogenase kinase (PDK) and glucose transporters (GLUTs) in modulating pulmonary fibrosis and glucose metabolism. Additionally, critical regulatory factors such as transforming growth factor-beta (TGF-ß), interleukin-1 beta (IL-1ß), and hypoxia-inducible factor 1 subunit alpha (HIF-1α) were discussed, demonstrating their impact on both PF and glucose metabolic pathways. It underscores the pivotal role of AMP-activated protein kinase (AMPK) in this interplay, drawing connections between diabetes mellitus, insulin, insulin-like growth factors, and peroxisome proliferator-activated receptor gamma (PPARγ) with PF. This study emphasizes the role of key enzymes, regulators, and glucose transporters in fibrogenesis, suggesting the potential of targeting glucose metabolism for the clinical diagnosis and treatment of PF, and proposing new promising avenues for future research and therapeutic development.

Engineering Built-In Electric Field Microenvironment of CQDs/g-C3N4 Heterojunction for Efficient Photocatalytic CO2 Reduction.

Graphitic carbon nitride (CN), as a nonmetallic photocatalyst, has gained considerable attention for its cost-effectiveness and environmentally friendly nature in catalyzing solar-driven CO2 conversion into valuable products. However, the photocatalytic efficiency of CO2 reduction with CN remains low, accompanied by challenges in achieving desirable product selectivity. To address these limitations, a two-step hydrothermal-calcination tandem synthesis strategy is presented, introducing carbon quantum dots (CQDs) into CN and forming ultra-thin CQD/CN nanosheets. The integration of CQDs induces a distinct work function with CN, creating a robust interface electric field after the combination. This electric field facilitates the accumulation of photoelectrons in the CQDs region, providing an abundant source of reduced electrons for the photocatalytic process. Remarkably, the CQD/CN nanosheets exhibit an average CO yield of 120 µmol g-1, showcasing an outstanding CO selectivity of 92.8%. The discovery in the work not only presents an innovative pathway for the development of high-performance photocatalysts grounded in non-metallic CN materials employing CQDs but also opens new avenues for versatile application prospects in environmental protection and sustainable cleaning energy.

Isomerization Engineering of Oxygen-Enriched Carbon Quantum Dots for Efficient Electrochemical Hydrogen Peroxide Production.

Hydrogen peroxide (H2O2) has emerged as a kind of multi-functional green oxidants with extensive industrial utility. Oxidized carbon materials exhibit promises as electrocatalysts in the two-electron (2e-) oxygen reduction reaction (ORR) for H2O2 production. However, the precise identification and fabrication of active sites that selectively yield H2O2 present a serious challenge. Herein, a structural engineering strategy is employed to synthesize oxygen-doped carbon quantum dots (o-CQD) for the 2e- ORR. The surface electronic structure of the o-CQDs is systematically modulated by varying isomerization precursors, thereby demonstrating excellent electrocatalyst performance. Notably, o-CQD-3 emerges as the most promising candidate, showcasing a remarkable H2O2 selectivity of 96.2% (n = 2.07) at 0.68 V versus RHE, coupled with a low Tafel diagram of 66.95 mV dec-1. In the flow cell configuration, o-CQD-3 achieves a H2O2 productivity of 338.7 mmol gcatalyst -1 h-1, maintaining consistent production stability over an impressive 120-hour duration. Utilizing in situ technology and density functional theory calculations, it is unveil that edge sites of o-CQD-3 are facilely functionalized by C-O-C groups under alkaline ORR conditions. This isomerization engineering approach advances the forefront of sustainable catalysis and provides a profound insight into the carbon-based catalyst design for environmental-friendly chemical synthesis processes.

Amine-Functionalized Metal-Free Nanocarbon to Boost Selective CO2 Electroreduction to CO in a Flow Cell.

Highly efficient electrochemical CO2-to-CO conversion is a promising approach for achieving carbon neutrality. While nonmetallic carbon electrocatalysts have shown potential for CO2-to-CO utilization in H-type cells, achieving efficient conversion in flow cells at an industrial scale remains challenging. In this study, we present a cost-effective synthesis strategy for preparing ultrathin 2D carbon nanosheet catalysts through simple amine functionalization. The optimized catalyst, NCNs-2.5, demonstrates exceptional CO selectivity with a maximum Faradaic efficiency of 98% and achieves a high current density of 55 mA cm-2 in a flow cell. Furthermore, the catalyst exhibits excellent long-term stability, operating continuously for 50 h while maintaining a CO selectivity above 90%. The superior catalytic activity of NCNs-2.5 is attributed to the presence of amine-N active sites within the carbon lattice structure. This work establishes a foundation for the rational design of cost-effective nonmetallic carbon catalysts as sustainable alternatives to metals in energy conversion systems.

Naphthalene-based donor-acceptor covalent organic frameworks as an electron distribution regulator for boosting photocatalysis.

By incorporating the electron-rich naphthalene and electron-deficient triazine as an electron donor and an electron acceptor, a new donor-acceptor covalent organic framework as an electron distribution regulator was obtained for boosting photocatalytically oxidative coupling of benzylamines and selective oxidation of thioethers under the irradiation of green light (520 nm).

Synergistic Effects of Amine Functional Groups and Enriched-Atomic-Iron Sites in Carbon Dots for Industrial-Current-Density CO2 Electroreduction.

Metal phthalocyanine molecules with Me-N4 centers have shown promise in electrocatalytic CO2 reduction (eCO2R) for CO generation. However, iron phthalocyanine (FePc) is an exception, exhibiting negligible eCO2R activity due to a higher CO2 to *COOH conversion barrier and stronger *CO binding energy. Here, amine functional groups onto atomic-Fe-rich carbon dots (Af-Fe-CDs) are introduced via a one-step solvothermal molecule fusion approach. Af-Fe-CDs feature well-defined Fe-N4 active sites and an impressive Fe loading (up to 8.5 wt%). The synergistic effect between Fe-N4 active centers and electron-donating amine functional groups in Af-Fe-CDs yielded outstanding CO2-to-CO conversion performance. At industrial-relevant current densities exceeding 400 mA cm-2 in a flow cell, Af-Fe-CDs achieved >92% selectivity, surpassing state-of-the-art CO2-to-CO electrocatalysts. The in situ electrochemical FTIR characterization combined with theoretical calculations elucidated that Fe-N4 integration with amine functional groups in Af-Fe-CDs significantly reduced energy barriers for *COOH intermediate formation and *CO desorption, enhancing eCO2R efficiency. The proposed synergistic effect offers a promising avenue for high-efficiency catalysts with elevated atomic-metal loadings.

Risk prediction and treatment assessment in glioma patients using SEER database: a prospective observational study.

OBJECTIVES: To use a nomogram to predict the risk of mortality and estimate the impact of current treatment on the prognosis of glioma patients. METHODS: A total of 3798 cases were obtained from the Surveillance Epidemiology and End Results database according to the selection criteria. A nomogram was built on the independent clinical factors screened by the variance inflation factor, univariate analyses and a multivariate Cox regression model. Then, categorising the overall population into high-risk, medium-risk and low-risk groups using nomogram-derived risk scores, to study the impact of treatment on different subgroups' survival outcomes. Furthermore, based on the postmatch cohorts, the influences of treatment on survival outcomes were assessed by the log-rank test. RESULT: Age, race, stage of disease, histological type, histological grade, surgery, radiotherapy and chemotherapy were identified as the independent prognostic factors. A nomogram with good discrimination and consistency was built. Generally, the patients who underwent surgery, radiotherapy and chemotherapy were more likely to achieve better prognosis than those who did not, except for those who received radiotherapy in the low-risk cohort and those who underwent surgery in the high-risk cohort. Furthermore, the isocitrate dehydrogenase 1/2 (IDH1/2) wild-type patients with surgery, radiotherapy or chemotherapy tended to have higher survival probabilities, while some inconsistent results were observed in the IDH mutant-type cohort. CONCLUSION: Surgery, radiotherapy and chemotherapy improved the prognosis, while appropriate selection of topical treatment for the low-risk or high-risk patients deserves further consideration. IDH status gene might be a reliable indicator of therapeutic effectiveness.

Multimodal evaluation of the bloodstream alteration before and after combined revascularization for Moyamoya disease.

Objective: This study aimed to explore the hemodynamic changes before and after anastomosis in patients with Moyamoya disease (MMD) using multiple models. Methods: We prospectively enrolled 42 MMD patients who underwent combined revascularization. Intraoperative FLOW800 was performed before and after anastomosis, and parameters was collected, including maximum intensity, delay time, rise time, slope, blood flow index, and microvascular transit time (MVTT). Additionally, preoperative and postoperative hemodynamic parameters were measured using color Doppler ultrasonography (CDUS), including peak systolic velocity, end-diastolic velocity, resistance index (RI), pulsatility index (PI), and flow volume. Subsequently, the correlation between FLOW800 and CDUS parameters was explored. Results: A total of 42 participants took part with an average age of 46.5 years, consisting of 19 men and 23 women. The analysis of FLOW800 indicated that both the delay time and rise time experienced a substantial decrease in both the recipient artery and vein. Additionally, the MVTT was found to be significantly reduced after the surgery (5.7 ± 2.2 s vs. 4.9 ± 1.6, p = 0.021). However, no statistically significant differences were observed among the other parameters. Similarly, all postoperative parameters in CDUS hemodynamics exhibited significant alterations in comparison to the preoperative values. The correlation analysis between FLOW800 and CDUS parameters indicated a significant association between MVTT and RI and PI, no significant relationships were found among the other parameters in the two groups. Conclusion: The hemodynamic outcomes of the donor and recipient arteries demonstrated significant changes following bypass surgery. The parameter of time appears to be more precise and sensitive in assessing hemodynamics using FLOW800. Multiple evaluations of hemodynamics could offer substantial evidence for perioperative management.

Graphene Quantum Dot-Mediated Atom-Layer Semiconductor Electrocatalyst for Hydrogen Evolution.

The hydrogen evolution reaction performance of semiconducting 2H-phase molybdenum disulfide (2H-MoS2) presents a significant hurdle in realizing its full potential applications. Here, we utilize theoretical calculations to predict possible functionalized graphene quantum dots (GQDs), which can enhance HER activity of bulk MoS2. Subsequently, we design a functionalized GQD-induced in-situ bottom-up strategy to fabricate near atom-layer 2H-MoS2 nanosheets mediated with GQDs (ALQD) by modulating the concentration of electron withdrawing/donating functional groups. Experimental results reveal that the introduction of a series of functionalized GQDs during the synthesis of ALQD plays a crucial role. Notably, the higher the concentration and strength of electron-withdrawing functional groups on GQDs, the thinner and more active the resulting ALQD are. Remarkably, the synthesized near atom-layer ALQD-SO3 demonstrate significantly improved HER performance. Our GQD-induced strategy provides a simple and efficient approach for expanding the catalytic application of MoS2. Furthermore, it holds substantial potential for developing nanosheets in other transition-metal dichalcogenide materials.

Intrinsic Photostability in Dithiolonaphthalimide Achieved by Disulfide Bond-Induced Excited-State Quenching.

Disulfide bridges common in proteins show excellent photostability achieved by ultrafast internal conversion and maintain the stability of the tertiary structure. When disulfide bonds exist in aromatic compounds, the rigid chemical structure may affect the cleavage and reforming dynamics of disulfide bonds. In this work, a model compound with a disulfide five-membered-ring structure, 4,5-dithiolo-N-(2,6-dimethylphenyl)-1,8-naphthalimide (DTDPNI), is selected to elaborate the effect of disulfide modification on the excited-state deactivation mechanism. Quantum chemical calculations show that the S-S stretching leads to a dramatic decrease in the energy gap between the S1 and S0 states, similar to the situation in 1,2-dithiane. Due to the efficient nonradiative process, the excited-state lifetime of DTDPNI resolved by ultrafast spectroscopy is determined to be ∼20 ps. It is found that the excellent photostability is achieved by ultrafast excited-state quenching induced by the S-S stretching, rather than the cleavage of the disulfide bond; even the disulfide bridge is in a very rigid aromatic molecular system.

Interfacial engineering of a vertically stacked graphene/h-BN heterostructure as an efficient electrocatalyst for hydrogen peroxide synthesis.

Recently, it was reported that an in-plane graphene (G)/hexagonal boron nitride (h-BN) (G/h-BN) heterostructure provided the catalytic activity for H2O2 synthesis by the 2 e- oxygen reduction reaction (ORR). However, there are few reports on the vertically stacked G/h-BN heterostructure, which refers to the stacking of graphene domains on the surface of h-BN. Herein, a simulated chemical vapor deposition method is proposed for fabricating a heterostructure of abundant vertically stacked G/h-BN by in situ growing graphene quantum dots (GQDs) on porous h-BN sheets. The performance of our vertically stacked heterostructure catalyst is superior to that of reported carbon-based electrocatalysts under an alkaline environment, with an H2O2 selectivity of 90-99% in a wide potential range (0.35 V-0.7 V vs. RHE), over 90% faradaic efficiency, and high mass activity of 1167 mmol gcatalyst-1 h-1. The experimental results and density functional theory (DFT) simulation verified that the vertically stacked heterostructure exhibits an excellent catalytic performance for the 2 e- ORR, and the edge B atoms in the B-centered AB stacking model are the most active catalytic sites. This research adequately demonstrates the promising catalytic activity of the vertically stacked G/h-BN heterostructure and provides a facile route for fabricating other vertically stacked heterostructures.

Biosynthesized gold nanoparticles that activate Toll-like receptors and elicit localized light-converting hyperthermia for pleiotropic tumor immunoregulation.

Manipulating the tumor immune contexture towards a more active state can result in better therapeutic outcomes. Here we describe an easily accessible bacterial biomineralization-generated immunomodulator, which we name Ausome (Au + [exo]some). Ausome comprises a gold nanoparticle core covered by bacterial components; the former affords an inducible hyperthermia effect, while the latter mobilizes diverse immune responses. Multiple pattern recognition receptors actively participate in Ausome-initiated immune responses, which lead to the release of a broad spectrum of pro-inflammatory cytokines and the activation of effector immune cells. Upon laser irradiation, tumor-accumulated Ausome elicits a hyperthermic response, which improves tissue blood perfusion and contributes to enhanced infiltration of immunostimulatory modules, including cytokines and effector lymphocytes. This immune-modulating strategy mediated by Ausome ultimately brings about a comprehensive immune reaction and selectively amplifies the effects of local antitumor immunity, enhancing the efficacy of well-established chemo- or immuno-therapies in preclinical cancer models in female mice.

Recommendation of SLM Process Parameters Based on Analytic Hierarchy Process and Weighted Particle Swarm Optimization for High-Temperature Alloys.

Selective laser melting (SLM) of high-temperature alloys involves intricate interdependencies among key process parameters, such as laser power and scanning speed, affecting properties such as density and tensile strength. However, relying solely on experiential knowledge for process parameter design often hampers the precise attainment of target requirements. To address this challenge, we propose an innovative approach that integrates the analytic hierarchy process (AHP) and weighted particle swarm optimization (WPSO) to recommend SLM process parameters for high-temperature alloy fabrication. Our proposed AHP-WPSO model consists of three main steps. First, a comprehensive historical database is established, capturing the process parameters and performance metrics of high-temperature alloy SLM parts. Utilizing an AHP framework, we compute the performance similarity between target and historical cases, applying rational thresholds to identify analogous cases. When suitable analogs are elusive, the model seamlessly transitions to the second step. Here, the WPSO model optimizes and recommends process parameters according to target specifications. Lastly, our experimental validation of the GH4169 high-temperature alloy through SLM experiments corroborates the effectiveness of our AHP-WPSO model in making process parameter recommendations. The outcomes underscore the model's high accuracy, attaining a recommendation precision of 99.81% and 96.32% when historical analogs are present and absent, respectively. This innovative approach offers a robust and reliable solution to the challenges posed in SLM process parameter optimization for high-temperature alloy applications.

Functional Group Modulation in Carbon Quantum Dots for Accelerating Photocatalytic CO2 Reduction.

This study investigates the mechanism behind the enhanced photocatalytic performance of carbon quantum dot (CQD)-induced photocatalysts. Red luminescent CQDs (R-CQDs) were synthesized using a microwave ultrafast synthesis strategy, exhibiting similar optical and structural properties but varying in surface functional group sites. Model photocatalysts were synthesized by combining R-CQDs with graphitic carbon nitride (CN) using a facile coupling technique, and the effects of different functionalized R-CQDs on CO2 reduction were investigated. This coupling technique narrowed the band gap of R1-CQDs/CN, made the conduction band potentials more negative, and made photogenerated electrons and holes less likely to recombine. These improvements greatly enhanced the deoxygenation ability of the photoinduced carriers, increased light absorption of solar energy, and raised the carrier concentration, resulting in excellent stability and remarkable CO production. R1-CQDs/CN demonstrated the highest photocatalytic activity, with CO production up to 77 µmol g-1 within 4 h, which is approximately 5.26 times higher than that of pure CN. Our results suggest that the superior photocatalytic performance of R1-CQDs/CN arises from its strong internal electric field and high Lewis acidity and alkalinity, attributed to the abundant pyrrolic-N and oxygen-containing surface groups, respectively. These findings offer a promising strategy for producing efficient and sustainable CQD-based photocatalysts to address global energy and environmental problems.