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Access to sustainable energy is paramount in today’s world, with a significant emphasis on solar and water-based energy sources. Herein, we develop photo-responsive ionic dye-sensitized covalent organic framework membranes. These innovative membranes are designed to significantly enhance selective ion transport by exploiting the intricate interplay between photons, electrons, and ions. The nanofluidic devices engineered in our study showcase exceptional cation conductivity. Additionally, they can adeptly convert light into electrical signals due to photoexcitation-triggered ion movement. Combining the effects of salinity gradients with photo-induced ion movement, the efficiency of these devices is notably amplified. Specifically, under a salinity differential of 0.5/0.01 M NaCl and light exposure, the device reaches a peak power density of 129 W m −2 , outperforming the current market standard by approximately 26-fold. Beyond introducing the idea of photoelectric activity in ionic membranes, our research highlights a potential pathway to cater to the escalating global energy needs. Artificial ion channels with multiple functions provide exciting opportunities to emulate natural processes and enhance energy conversion. Here, the authors introduce a family of photoelectrically responsive ionic covalent organic frameworks membranes for solar energy and salinity gradient energy conversion.

Membrane reactors are known for their efficiency and superior operability compared to traditional batch processes, but their limited diversity poses challenges in meeting various reaction requirements. Herein, we leverage the molecular tunability of covalent organic frameworks (COFs) to broaden their applicability in membrane reactors. Our COF membrane demonstrates an exceptional ability to achieve complete conversion in just 0.63 s at room temperature—a benchmark in efficiency for Knoevenagel condensation. This performance significantly surpasses that of the corresponding homogeneous catalyst and COF powder by factors of 176 and 375 in turnover frequency, respectively. The enhanced concentration of reactants and the rapid removal of generated water within the membrane greatly accelerate the reaction, reducing the apparent activation energy. Consequently, this membrane reactor enables reactions that are unattainable using both COF powders and homogeneous catalysts. Considering the versatility, our findings highlight the substantial promise of COF-based membrane reactors in organic transformations. Membrane reactors are efficient alternatives to traditional bath process, yet their limited diversity challenges their applicability to various reaction requirements. Here, the authors report covalent organic framework membrane reactors applied to the Knoevenagel condensation with enhanced performance as compared to homogeneous catalysts.

Efficient energy conversion using ions as carriers necessitates membranes that sustain high permselectivity in high salinity conditions, which presents a significant challenge. This study addresses the issue by manipulating the linkages in covalent-organic-framework membranes, altering the distribution of electrostatic potentials and thereby influencing the short-range interactions between ions and membranes. We show that a charge-neutral covalent-organic-framework membrane with β-ketoenamine linkages achieves record permselectivity in high salinity environments. Additionally, the membrane retains its permselectivity under temperature gradients, providing a method for converting low-grade waste heat into electrical energy. Experiments reveal that with a 3 M KCl solution and a 50 K temperature difference, the membrane generates an output power density of 5.70 W m −2 . Furthermore, guided by a short-range ionic screening mechanism, the membrane exhibits adaptable permselectivity, allowing reversible and controllable operations by finely adjusting charge polarity and magnitude on the membrane’s channel surfaces via ion adsorption. Notably, treatment with K 3 PO 4 solutions significantly enhances permselectivity, resulting in a giant output power density of 20.22 W m −2 , a 3.6-fold increase over the untreated membrane, setting a benchmark for converting low-grade heat into electrical energy. Membranes with high permselectivity in high salinity conditions are desirable for efficient energy conversion. Here, the authors address the challenge by modifying the distribution of electrostatic potentials in the linkages of covalent organic framework membranes and apply the material to the conversion of low-grade waste heat into electrical energy.

Selective extraction of KCl from complex salt lake brines remains a challenging task due to the presence of competing ions and the high energy requirements of conventional separation methods. To overcome these limitations, we have developed a biomimetic separation system that integrates three-dimensional (3D) covalent organic framework (COF) membranes with redox-mediated energy harvesting. These COF membranes are designed with sub-nanometer cavity channels decorated with oxygen-containing groups, which enable fine-tuning of electrostatic potential. This design allows for the simultaneous separation of anions and cations through valence-dependent short-range interactions. By coupling the COF membranes with Ag/AgCl redox pairs, the system converts the salinity gradient across the membrane into an internal electric field, facilitating autonomous ion transport without the need for external energy input. The system achieves over fivefold higher flux rates for K + and Cl⁻ (2.6 and 3.2 mol m –2 h –1 , respectively) and demonstrates outstanding separation performance with Cl – /SO 4 2–  = 332, K + /Mg 2+ = 60, K + /Na + = 7, and K + /Li + = 11, substantially exceeding the passive diffusion ratios of 253, 27, 3, and 5, respectively. This work presents a sustainable, scalable approach for extracting valuable resources from complex brines, combining innovative biomimetic membrane design with redox-assisted process engineering, offering a promising solution to the energy and selectivity challenges in industrial ion separation. Natural salt lake brines contain various ions, making the selective extraction of KCl challenging. Here, the authors combine 3D covalent organic framework membranes with redox-mediated salinity gradient harvesting to enable the low-energy separation of anions and cations.

Background Lymphovascular invasion (LVI) predicts a poor outcome of breast cancer (BC), but LVI can only be postoperatively diagnosed by histopathology. We aimed to determine whether quantitative parameters of dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) can preoperatively predict LVI and clinical outcome of BC patients. Methods A total of 189 consecutive BC patients who underwent multiparametric MRI scans were retrospectively evaluated. Quantitative ( K trans , V e , K ep ) and semiquantitative DCE-MRI parameters (W − in , W − out , TTP), and clinicopathological features were compared between LVI-positive and LVI-negative groups. All variables were calculated by using univariate logistic regression analysis to determine the predictors for LVI. Multivariate logistic regression was used to build a combined-predicted model for LVI-positive status. Receiver operating characteristic (ROC) curves evaluated the diagnostic efficiency of the model and Kaplan-Meier curves showed the relationships with the clinical outcomes. Multivariate analyses with a Cox proportional hazard model were used to analyze the hazard ratio (HR) for recurrence-free survival (RFS) and overall survival (OS). Results LVI-positive patients had a higher K ep value than LVI-negative patients (0.92 ± 0.30 vs. 0.81 ± 0.23, P  = 0.012). N2 stage [odds ratio (OR) = 3.75, P  = 0.018], N3 stage (OR = 4.28, P  = 0.044), and K ep value (OR = 5.52, P  = 0.016) were associated with LVI positivity. The combined-predicted LVI model that incorporated the N stage and K ep yielded an accuracy of 0.735 and a specificity of 0.801. The median RFS was significantly different between the LVI-positive and LVI-negative groups (31.5 vs. 34.0 months, P  = 0.010) and between the combined-predicted LVI-positive and LVI-negative groups (31.8 vs. 32.0 months, P  = 0.007). The median OS was not significantly different between the LVI-positive and LVI-negative groups (41.5 vs. 44.0 months, P  = 0.270) and between the combined-predicted LVI-positive and LVI-negative groups (42.8 vs. 43.5 months, P  = 0.970). LVI status (HR = 2.40), N2 (HR = 3.35), and the combined-predicted LVI model (HR = 1.61) were independently associated with disease recurrence. Conclusion The quantitative parameter of K ep could predict LVI. LVI status, N stage, and the combined-predicted LVI model were predictors of a poor RFS but not OS.

Amyloid-β (Aβ) deposits and some proteins play essential roles in the pathogenesis of Alzheimer's disease (AD). Amide proton transfer (APT) imaging, as an imaging modality to detect tissue protein, has shown promising features for the diagnosis of AD disease. In this study, we chose 10 AD model rats as the experimental group and 10 sham-operated rats as the control group. All the rats underwent a Y-maze test before APT image acquisition, using saturation with frequency alternating RF irradiation (APT ) method on a 7.0 T animal MRI scanner. Compared with the control group, APT (3.5 ppm) values of brain were significantly reduced in AD models ( < 0.002). The APT imaging is more significant than APT imaging ( < 0.0001). AD model mice showed spatial learning and memory loss in the Y-maze experiment. In addition, there was significant neuronal loss in the hippocampal CA1 region and cortex compared with sham-operated rats. In conclusion, we demonstrated that APT imaging could potentially provide molecular biomarkers for the non-invasive diagnosis of AD. APT MRI could be used as an effective tool to improve the accuracy of diagnosis of AD compared with conventional APT imaging.