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An Ultra-Stable 2D Linear Polymer Cathode for High-Performance Aqueous Zinc-Organic Batteries
No full textTwo-dimensional structure of cathode materials possesses fast kinetics in aqueous zinc ion batteries. However, in organic linear polymers it is rare to form two-dimensional structures due to the bond rotations of the polymerization reaction. In this work, inspired by the process of forming carbon fibers from polyacrylonitrile, a novel two-dimensional linear polymer (2DLP) of poly(2H,11H-bis[l,4]triazino[3,2-b : 3′,2′-m]triphenodithiazine-3,12-diyl-2,11-diyli-dene-11,12-bis[methyldene]) (PTL) cathode materials were prepared for aqueous zinc-ion battery cathode materials by designing ladder structure polymer molecules with highly restricted bond rotations. PTL possess fast cations diffusion (4.27×10−7 cm−1 s−1) due to its layered structure. Moreover, the PTL electrodes exhibit an ultra-long cycle stability (7000 cycles still remain 87 % capacity remains). Meanwhile, as PTL mass loading increase from 3.13 to 6.27 mg cm−2, the specific capacity kept 98 % retention after 100 cycles. Besides, the assembled Zn/PTL flexible pack battery exhibits a 6.6 mAh capacity at 0.5 A g−1. Furthermore, though a range of ex site analysis, it was supported that the charge storage mechanism of PTL is driven by the imine moiety, and accompanies by the insertion and extraction of Zn2+/H+ ions. This work attempts to provide a new sight of improve the poor ion diffusion coefficient of organic materials.link_to_subscribed_fulltex
Design of asymmetric electrolytes for aqueous zinc batteries
No full textAqueous Zn batteries are gaining increasing research attention in the energy storage area due to their intrinsic safety, potentially low cost and environmental friendliness; however, the zinc dendrite formation, zinc corrosion, passivation and the hydrogen evolution reaction induced by water at the anode side, and materials dissolution as well as intrinsic poor reaction kinetics at cathode side in aqueous systems, seriously shorten the cycling life and decrease energy density of batteries and greatly hinder their development. Recent advancements in asymmetric electrolytes with various functions are promising to overcome such challenges for zinc batteries at the same time. It has been proved that the applications of asymmetric electrolytes show significant contributions in the field of zinc-based batteries in suppressing side reactions while maintaining electrochemical performance to satisfy both anode and cathode. Therefore, this perspective summarizes recent advancements in asymmetric electrolytes’ design and applications for zinc batteries and outlines opportunities and future challenges, expecting continued research attention in this area.link_to_subscribed_fulltex
Hydrophobic-unit-regulated hydrogel electrolytes with high water content and low salt concentration for high-voltage aqueous batteries
No full textCommon aqueous electrolytes with extended electrochemical stability windows (ESWs) have a low water content; thus, water molecules are well confined. However, confinement to metal cations of these aqueous electrolytes, which leads to poor compatibility with available metal-ion charge carriers, has been overlooked. We demonstrated that hydrogel electrolytes with high water content and low salt concentration exhibit wide ESWs through effective water interactions. Moreover, these electrolytes have well-suppressed confinement to metal cations, leading to high battery performance and excellent compatibility with charge carriers. The fabricated hydrophobic-unit-regulated hydrogel electrolyte (HHE) features trace amounts of hydrophobic moieties, which disperse evenly in the HHEs. The hydrophobicity in the vicinity of hydrophilic groups enhances their hydrogen bond strength with water molecules, resulting in an ESW of 3.3 V at a water concentration of 68 wt %. The 2.3, 1.9, and 1.75 V discharge plateaus were observed in aqueous Li4Ti5O12||LiMn2O4, Zn||MnO2, and potassium-ion batteries, respectively.link_to_subscribed_fulltex
Time-evolved growth of semi-aromatic polyamide nanofilms and their structure-performance relationship: Mechanistic insights and implications for nanofiltration membrane synthesis
Get PDFThe separation performance of thin film composite nanofiltration (NF) membranes is governed by a semi-aromatic polyamide film. Compared to fully aromatic polyamide films with a well-known self-limiting behavior, the growth kinetics of semi-aromatic polyamide films and the corresponding regulation mechanisms have not been fully understood. This study systematically investigated the time-evolved growth of a piperazine (PIP)-based polyamide film at a free interface over prolonged interfacial polymerization reaction time (up to 60 min). For the first time, we revealed a two-stage growth kinetics, with the film growth rate in the later stage (7.0 nm min−1) one order of magnitude slower than the initial rate (68.2 nm min−1) as a result of reduced availability of PIP monomers. This two-stage growth mechanism led to an asymmetric film structure, with compelling characterization results (i.e., crosslinking degree, film density, and pore size) showing that the newly formed polyamide under the reduced PIP availability was much looser than the incipient film. We demonstrated that such asymmetric structure had profound impact on the separation performance of the resulting NF membrane through mechanisms such as internal concentration polarization and gutter effect. The mechanistic insights into the growth-structure-performance relationship of semi-aromatic polyamide films could guide the synthesis of high-performance NF membranes.published_or_final_versio
Origin of Eocene adakitic porphyries in the Binchuan–Weishan area, southeastern Tibetan Plateau: Constraints on the initial left-lateral strike slip of the Diancangshan–Ailaoshan tectonic zone
No full textThe India–Eurasia collision during Cenozoic era has led to large-scale uplift and lithospheric extrusion of the central Tibetan Plateau. As a vital boundary for accommodating the compressive stress in the interior of the plateau, the Diancangshan–Ailaoshan tectonic zone (DATZ) in Yunnan Province has witnessed to this evolutionary history and documented the tectonic processes. As the indication of the collisional process at depth, the Cenozoic potassic magmatic rocks that developed along the DATZ are the critical lithological probe for elucidating the deep dynamic mechanisms underlying the India–Eurasia collision and their connection with the plateau's lithospheric extrusion. In this paper, we present new zircon U-Pb, Hf and O isotopic data, along with whole-rock major and trace elemental compositions, and whole-rock Sr-Nd isotopic data of Eocene porphyries located at the junction of the Diancangshan and Ailaoshan metamorphic massifs in Yunnan Province. Zircon U-Pb dating results indicate that they were emplaced at 37–35 Ma. Geochemically, all the studied porphyries exhibit an affinity to potassic adakitic rocks with the enrichment in K2O (K2O = 3.88–5.69 wt%), high Sr contents (mostly >400 ppm), elevated Sr/Y ratios (30–106), and low Y and Yb contents, indicating an origin from the partial melting of the thickened mafic continental lower crust which is garnet-bearing amphibolite. However, the disparity in zircon Hf and O isotopic compositions between the Binchuan–Midu and Weishan granitic porphyries reflects their different sources. They are the Neoproterozoic and Late Paleozoic mafic lower crust that formed during the Neoproterozoic and Paleo-Tethyan subduction, respectively. By integrating regional data, including structural feature, metamorphism, sedimentation and magmatism patterns, we propose that the generation of the late Eocene (37–35 Ma) potassic rocks along the Jinshajiang–Ailaoshan tectonic zone in Yunnan Province was a consequence of the southeastward extrusion of the central Tibetan Plateau lithosphere, coupled with the left-lateral shearing of the DATZ and the rotating of the Lanping–Simao and Yangtze blocks.</p
Semantic segmentation of building façade materials and colors for urban conservation
Get PDFBuilding façade materials are fundamental to understanding cultural heritage and preserving the historic urban environment. While traditional material analysis requires extensive manual effort, this study introduces an automated methodology of material identification and feature extraction. We construct the Building Façade Material Segmentation (BFMS) database, which surpasses previous datasets in its alignment with architectural standards and the diversity of material categories included. Based on the database, we develop a transformer-based semantic segmentation model that achieves an overall accuracy of 76.5%. Furthermore, the algorithm to extract detailed textures and colors for each material is formulated with K-means clustering and grid statistics. Applied in the Taiping Alley, a historic area in Jingdezhen, the methodology demonstrates robustness and efficiency, yielding valuable guidance for architectural landscape assessment and urban renewal planning. The study promotes the application of cutting-edge deep learning algorithms in urban conservation and contributes to the broader understanding of urban material characteristics.published_or_final_versio
Condylar High-dimensional Image Feature Analysis for Skeletal Class Ⅲ Malocclusion
No full textObjectives: This study aimed to detect the high-dimensional image features of mandibular condyles specific to patients with skeletal Class Ⅲ malocclusion.Methods: Lateral cephalograms (LC) and craniofacial cone beam computed tomography (CBCT) images of 51 adult patients were collected. The patients were then diagnosed with skeletal Class Ⅰ, Ⅱ, or Ⅲ malocclusion according to the measurement on LCs. In CBCT images, the condyles were segmented using 3D Slicer. Among 102 condyles, 81 of them were randomly selected as the training set for the deep learning (DL) model and the remaining for the test set. The ViT3D model for the skeletal Class Ⅲ malocclusion identification task was developed. Additionally, following image segmentation, radiomic features were then extracted and selected. Those features with intraclass correlation (ICC) over 0.9 were included in the repeated measure analysis to compare the feature difference among groups at the significance level of 0.05.Results: According to the cephalometric analysis, 18, 15 and 18 patients were diagnosed with skeletal Class Ⅰ, Ⅱ, and Ⅲ, with the ANB angle of 2.43±1.24, 7.87±1.91 and -2.21±1.52, respectively (PConclusions: In the DL model using CBCT images, the mandibular condyle may serve as a potential diagnostic target for identifying skeletal Class Ⅲ malocclusion. Further, variations in quantitative high-dimensional image features on condyles exist among different malocclusions, aiding in refining diagnostic models and enhancing our understanding of mandibular growth mechanisms.</p
The effectiveness and mechanism of parent management training and mindful parenting program
No full textParent Management Training (PMT) is a traditional parenting intervention that aims to equip parents with effective parenting strategies. This approach has demonstrated effectiveness in improving parent-child relationships, reducing parental stress and child behavioral problems. In recent decades, there has been a growing interest in applying mindfulness in parent support. Mindful Parenting (MP) programs have shown positive effects on parental stress, parent–child relationships and parent’s emotional competence. Given the emergence of MP in the field of parenting, there is a need to compare the effectiveness of this new intervention with that of PMT. It is also important to investigate the mechanisms of change in these two interventions. To address these needs, the current study had two objectives: 1) to examine the effectiveness of PMT and MP as preventive intervention using a randomized controlled trial, 2) to investigate the mechanisms of change in PMT and MP program with the intention to reveal how these interventions work.
One hundred and eighty-nine parents of primary school children were randomly assigned to either the PMT, MP, or waitlist-control group. Data were collected at baseline, post-intervention, and two-month follow-up. With reference to Objective 1, findings indicated that both PMT and MP program were effective in improving parenting practice, parent’s mental health and parent-child relationships, and reducing child behavioral problems. The results also highlighted the unique strengths of each intervention. While PMT induced broader and more lasting change in parenting practice, and stronger effect in parent’s sense of competence, MP program produced more lasting positive impact to parent’s emotional competence, and had delayed effect on parent’s perception on child behavioral problems. It also changed parental attitudes and brought benefits beyond the parent-child context. These findings support the application of PMT and MP program as preventive interventions, each with their unique relative strengths.
To address Objective 2, a longitudinal mediation analysis using structural equation modelling was run with parent-child relationships and child behavioral problems as outcome variables whereas parenting knowledge and emotional competence as the first layer of mediators and parenting practice as the second layer of mediator. Unique mechanisms were identified in the two interventions. Parenting knowledge was found to be a mediator of PMT’s but not MP’s effect on positive parenting practice. However, parent’s emotional competence was found to mediate the effect of both PMT and MP on parenting practice. Findings also revealed the similarities in the mechanism of change in PMT and MP programs on parent-child relationships and child behavioral problems. In both programs, positive parenting practice was found to be the sole mediator of the effect of interventions on parent-child relationships, and negative parenting practice was found to be the sole mediator of the effect on child-behavioral problems, respectively. No moderating effect was found for either household income or parent's emotional competence.
The study advanced our understanding of the effectiveness and mechanism of change in parenting interventions. Implications, limitations and future research direction were discussed.published_or_final_versionPsychologyDoctoralDoctor of Philosoph
Flood Mapping and Assessment of Crop Damage Based on Multi-Source Remote Sensing: A Case Study of the “7.27” Rainstorm in Hebei Province, China
No full textFlooding is among the world’s most destructive natural disasters. From 27 July to 1 August 2023, Zhuozhou City and surrounding areas in Hebei Province experienced extreme rainfall, severely impacting local food security. To swiftly map the spatial and temporal distribution of the floodwaters and assess the damage to major crops, this study proposes a water body identification method with a dual polarization band combination for synthetic-aperture radar (SAR) data to solve the differences in water body feature recognition in SAR due to different polarization modes. Based on the SAR water body extent, the flood inundation extent was mapped with GF-6 optical data. In addition, Landsat-8 data were used to generate information on significant crops in the study area, while Sentinel-2 data and the Google Earth Engine (GEE) platform were used to classify the extent of crop damage. The results indicate that the flood inundated 700.51 km2, 14.10% of the study area. Approximately 40,700 hectares (ha) or 8.46% of the main crops were affected, including 33,700 ha of maize, 4300 ha of vegetables, and 2800 ha of beans. Moderate crop damage was the most widespread, affecting 37.62% of the crops, while very extreme damage was the least, affecting 5.10%. Zhuozhou City experienced the most significant impact, with 13,700 ha of crop damage, accounting for 33.70% of the total. This study provides a computational framework for rapid flood monitoring using multi-source remote sensing data, which also serves as a reference for post-disaster recovery, agricultural production, and crop risk assessment.</p
LLM agent framework for intelligent change analysis in urban environment using remote sensing imagery
No full textExisting change detection methods often lack the versatility to handle diverse real-world queries and the intelligence for comprehensive analysis. This paper presents a general agent framework, integrating Large Language Models (LLM) with vision foundation models to form ChangeGPT. A hierarchical structure is employed to mitigate hallucination. The agent was evaluated on a curated dataset of 140 questions categorized by real-world scenarios, encompassing various question types (e.g., Size, Class, Number) and complexities. The evaluation assessed the agent's tool selection ability (Precision/Recall) and overall query accuracy (Match). ChangeGPT, especially with a GPT-4-turbo backend, demonstrated superior performance, achieving a 90.71 % Match rate. Its strength lies particularly in handling change-related queries requiring multi-step reasoning and robust tool selection. Practical effectiveness was further validated through a real-world urban change monitoring case study in Qianhai Bay, Shenzhen. By providing intelligence, adaptability, and multi-type change analysis, ChangeGPT offers a powerful solution for decision-making in remote sensing applications.</p