Heterocyclic-linked covalent organic frameworks (COFs) integrate organic units into extended structures, offering enhanced π-conjugation, stability, light absorption, and charge separation. Leveraging these properties, this perspective explores COF design for photocatalytic uranium extraction, highlighting the design strategy, photocatalytic performance, and future challenges. It guides the development of photocatalytic uranium extraction, promoting both environmental remediation and the security of nuclear fuel supply.
Scar formation results from nonregenerative healing after tissue injury. Complications may occur if the scar grows beyond a certain threshold. Superficial X-ray radiotherapy offers significant advantages as an adjuvant method for surgical treatment of scars. Following the widespread application of the superficial X-ray radiotherapy system SRT-100, accurate dose measurements are key to the implementation of superficial X-ray radiotherapy. In this study, the absorbed dose measured in superficial X-ray radiotherapy was traced to the primary standard based on air kerma. According to this principle, based on the technical parameters of the SRT-100 system, this study establishes the corresponding reference radiation qualities by relying on an industrial X-ray tube and uses a free-air ionization chamber to obtain the corresponding correction factors through experiments and simulations to realize absolute air kerma measurements and uncertainty evaluations. In this context, air kerma calibration and associated uncertainty evaluations were performed for the parallel-plate transfer ionization chambers PTW23342 and PTW23344. The results show that the mean energies of the fluence spectra simulated at the X-ray tube voltages of 50, 70, and 100 kV were 26.2, 34.1, and 44.7 keV, respectively. The measured results of the first half-value layer at the three tube voltages were 0.538, 1.146, and 2.190 mmAl. The air kerma of three radiation qualities were 1.487, 1.436, and 1.268 mGy/s. The expanded measurement uncertainty of air kerma by the free-air ionization chamber was 0.94 k = 2 ), and the expanded uncertainties of the calibration factor in the two transfer ionization chambers were 1.00 k=2 ) and 0.96 k=2 ).
The sustainable development of nuclear energy requires efficient and reusable materials for uranium extraction from seawater, where uranyl species exist at ultra-trace levels within complex coordination environments. To overcome the limitations of empirical, trial-and-error design, this study establishes U-Predict v1.0, a structure-performance database for uranium adsorbents, and introduces an interpretable machine learning framework for adsorption performance prediction and mechanistic analysis. Trained on over 220 samples and 54 structural descriptors, the Light Gradient Boosting Machine (LightGBM) model with engineered features and optimized hyperparameters achieved a training R2 of 0.9887 and a test R2 of 0.7501, indicating robust predictive performance under heterogeneous and literature-derived conditions. SHapley Additive exPlanations (SHAP) interpretation revealed that structural and environmental variables, particularly functional group chemistry, solution pH, and surface area, jointly govern uranium the maximum adsorption capacity (qmax) through nonlinear interactions, emphasizing the dual control of material composition and adsorption environment. Experimental validation using a representative high-performance covalent organic frameworks-based adsorbent confirmed the model’s predictive reliability, with the measured qmax of 342.2 mg g−1 showing reasonable agreement with the predicted value (449.3 mg g−1; 23.8
BACKGROUND:Iodide (I-) serves as a key indicator for monitoring 131I contamination in marine environments. However, rapid on-site detection remains challenging due to the short half-life of radionuclides and the complex nature of seawater. Traditional nanocatalysts exhibit limited catalytic activity under near-neutral conditions and poor selectivity in high-salinity environments. There is therefore an urgent need to develop a robust, instrument-free analytical platform that can meet on-site environmental monitoring requirements by combining high sensitivity with operational simplicity. RESULTS:In this study, Mn-modified MOF-808 (Mn/MOF-808) nanozymes were synthesised using a sustainable aqueous post-synthetic approach. The incorporation of Mn centers significantly altered the electronic structure of the MOF nodes, resulting in exceptional peroxidase-like activity across a wide pH range (3.5-8.0). We found that I- acts as a potent synergistic amplifier, greatly accelerating the catalytic oxidation of chromogenic substrates. The sensing system achieved an ultra-low limit of detection (LOD) of 0.63 nM for I-. To enable point-of-care testing (POCT), we developed a smartphone-integrated platform using a customised WeChat mini-program for digital image colorimetry. The test results showed no significant deviation from those obtained using the standard ICP-MS method. SIGNIFICANCE:This work presents a cost-effective ($0.104/test), rapid, and user-friendly approach for I- monitoring. The Mn/MOF-808 platform demonstrates superior anti-interference capability in various environmental water samples and simulated seawater (recoveries: 96.5%-103.2%). By bridging advanced nanozyme engineering with mobile digitization, this research offers a practical and scalable solution for real-time environmental monitoring and emergency diagnostics of radioactive contaminants, aligning with the principles of green analytical chemistry.
Facing global energy shortages and environmental pollution, photovoltaic-thermal (PV/T) systems demonstrate significant potential in building energy supply. However, standalone PV/T systems still face significant challenges in practical building applications: energy supply instability constrained by meteorological conditions, and temporal mismatch between energy production and end-use demand. To address these issues, this study proposes a multi-component integrated energy system combining photovoltaic-thermal collectors, water-source heat pumps, and underground thermal storage tanks, achieving combined electricity and heat supply in a 36-squaremeter laboratory. Four operational strategies were designed, with system performance analyzed via TRNSYS numerical modeling and validated through field experiments. Based on actual building loads and local meteorological data, a year-round comparative analysis of operational strategies demonstrated the energy-saving advantages of direct solar fresh air preheating over the conventional "collection-storage-supply" pathway. Results indicate stable system operation, maintaining indoor temperatures within the 19-21 degrees C range. The optimal strategy (daytime solar tile preheating of fresh air) achieved a system coefficient of performance (COP) of 3.10 with only 6.46% municipal electricity supplementation, significantly reducing building energy consumption. Through energy level matching (direct solar utilization for low-grade fresh air heating) and cross-seasonal thermal storage (achieved via underground tanks), the underground tank stores surplus solar energy during non-heating seasons for stable supply. Direct fresh air preheating avoids multi-stage energy losses, significantly enhancing energy utilization efficiency. This study provides a feasible low-carbon energy solution for buildings in cold regions, demonstrating promising engineering application prospects for reducing reliance on traditional energy sources for building heating.
