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Preparation of silver nanoparticles through the reduction of straw-extracted lignin and its antibacterial hydrogel

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 504-514页

作者： Lou Zhang Shuo Li Fu Tang Jingkai Zhang Yuetong Kang Hean Zhang Lidong Li state Key Laboratory for Advanced Metals and Materials School of Materials Science and EngineeringUniversity of Science and Technology BeijingBeijing 100083China

Silver nanoparticles(Ag NPs)have attracted attention in the field of biomaterials due to their excellent antibacterial ***,the reducing and stabilizing agents used for the chemical reduction of Ag NPs are usually toxic and may cause water *** this work,Ag NPs(31.2 nm in diameter)were prepared using the extract of straw,an agricultural waste,as the reducing and stabilizing *** analysis revealed that the straw extract contained lignin,the structure of which possesses phenolic hydroxyl and methoxy groups that facilitate the reduction of silver salts into Ag *** surfaces of Ag NPs were negatively charged due to the encapsulation of a thin layer of lignin molecules that prevented their *** the prepared Ag NPs were added to the precursor solution of acrylamide,free radical polymerization was triggered without the need for extra heating or light irradiation,resulting in the rapid formation of an Ag NP-polyacrylamide composite *** inhibition zone test proved that the composite hydrogel possessed excellent antibacterial ability due to the presence of Ag *** prepared hydrogel may have potential applications in the fabrication of biomedical materials,such as antibacterial dressings.

关键词： silver nanoparticles hydrogel straw extraction antibacterial

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Unveiling the promotion role of ZnO on Zn-Al spinel oxide for CO2 hydrogenation

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Journal of Energy Chemistry 2025年第1期100卷 18-25页

作者： Tongyao Wang Xinlong Yao Lixin Liang Hongyu Chen Pan Gao Guangjin Hou state Key Laboratory of Catalysis Dalian National Laboratory for Clean Energy Dalian Institute of Chemical Physics Chinese Academy of Sciences university of Chinese Academy of Sciences

The Zn-Al spinel oxide stands out as one of the most active catalysts for high-temperature methanol synthesis from CO2hydrogenation. However, the structure–activity relationship of the reaction remains poorly understood due to challenges in atomic-level structural characterizations and analysis of reaction intermediates. In this study, we prepared two Zn-Al spinel oxide catalysts via coprecipitation（ZnAl-C）and hydrothermal（ZnAl-H） methods, and conducted a comparative investigation in the CO2hydrogenation reaction. Surprisingly, under similar conditions, ZnAl-C exhibited significantly higher selectivity towards methanol and DME compared to ZnAl-H. Comprehensive characterizations using X-ray diffraction（XRD）, Raman spectroscopy and electron paramagnetic resonance（EPR） unveiled that ZnAl-C catalyst had abundant ZnO species on its surface, and the interaction between the ZnO species and its ZnAl spinel oxide matrix led to the formation of oxygen vacancies, which are crucial for CO2adsorption and activation. Additionally, state-of-the-art solid-state nuclear magnetic resonance（NMR） techniques,including ex-situ and in-situ NMR analyses, confirmed that the surface ZnO facilitates the formation of unique highly reactive interfacial formate species, which was readily hydrogenated to methanol and DME. These insights elucidate the promotion effects of ZnO on the ZnAl spinel oxide in regulating active sites and reactive intermediates for CO2-to-methanol hydrogenation reaction, which is further evidenced by the significant enhancement in methanol and DME selectivity observed upon loading ZnO onto the ZnAl-H catalyst. These molecular-level mechanism understandings reinforce the idea of optimizing the ZnO-ZnAl interface through tailored synthesis methods to achieve activity-selectivity balance.

关键词： Reaction intermediates

Effect of pouring time on microstructure and mechanical properties of centrifugal cast Ti-46Al alloy tubes

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China Foundry 2025年

作者： Gang Huang Qian Dang Cong-cong Su Jing Zhao Chi Zhang Guo-huai Liu Zhao-dong Wang The state Key Laboratory of Rolling and Automation Northeastern University School of Materials Science and Engineering Shenyang University of Technology

The grain size of TiAl alloy castings prepared by traditional casting process is coarse, thus showing poor mechanical properties. In this study, a new type of high performance Ti-46Al alloy tube prepared by vacuum centrifugal casting technology was introduced. This research comprehensively examined the influence of pouring time on the microstructure and mechanical performance of the castings, employing both experimental approaches and ProCast simulation methodologies. The findings indicate that prolonging the pouring time facilitates a microstructural evolution from coarse columnar grains to refined equiaxed grains. Under the condition of pouring temperature of 1,600 °C, rotation speed of 800 r·min-1and pouring time of 6 s, the tensile strength of Ti-46Al alloy at room temperature reaches 650 MPa, and the tensile strength at 800 °C reaches 705 MPa, which is significantly higher than that of traditional as-cast Ti-Al alloy.

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Exploration of Gas‑Dependent Self‑Adaptive Reconstruction Behavior of Cu_(2)O for Electrochemical CO_(2)Conversion to Multi‑Carbon Products

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Nano-Micro Letters 2025年第3期17卷 280-296页

作者： Chaoran Zhang Yichuan Gu Qu Jiang Ziyang Sheng Ruohan Feng Sihong Wang Haoyue Zhang Qianqing Xu Zijian Yuan Fang Song state Key Laboratory of Metal Matrix Composites School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China

Structural reconstruction of electrocatalysts plays a pivotal role in catalytic performances for CO_(2)reduction reaction(CO_(2)RR),whereas the behavior is by far superficially ***,we report that CO_(2)accessibility results in a universal self-adaptive structural reconstruction from Cu_(2)O to Cu@CuxO composites,ending with feeding gas-dependent microstructures and catalytic *** CO_(2)-rich atmosphere favors reconstruction for CO_(2)RR,whereas the CO_(2)-deficient one prefers that for hydrogen evolution *** the assistance of spectroscopic analysis and theoretical calculations,we uncover a CO_(2)-induced passivation behavior by identifying a reductionresistant but catalytic active Cu(I)-rich amorphous layer stabilized by*CO ***,we find extra CO production is indispensable for the robust production of *** inverse correlation between durability and FECO/FEC2H4 is disclosed,suggesting that the selfstabilization process involving the absorption of*CO intermediates on Cu(I)sites is essential for durable *** by this insight,we design hollow Cu_(2)O nanospheres for durable and selective CO_(2)RR electrolysis in producing *** work recognizes the previously overlooked passivation reconstruction and self-stabilizing behavior and highlights the critical role of the local atmosphere in modulating reconstruction and catalytic processes.

关键词： CO_(2)reduction reaction Electrocatalysts Cu_(2)O Reconstruction Self-adaptive electrocatalysis

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SEFormer:A Lightweight CNN-Transformer Based on Separable Multiscale Depthwise Convolution and Efficient Self-Attention for Rotating Machinery Fault Diagnosis

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Computers, Materials & Continua 2025年第1期82卷 1417-1437页

作者： Hongxing Wang Xilai Ju Hua Zhu Huafeng Li state Key Laboratory of Mechanics and Control for Aerospace Structures Nanjing University of Aeronautics and AstronauticsNanjing210016China School of Computer Science and Engineering Nanyang Technological UniversitySingapore639798Singapore

Traditional data-driven fault diagnosis methods depend on expert experience to manually extract effective fault features of signals,which has certain ***,deep learning techniques have gained prominence as a central focus of research in the field of fault diagnosis by strong fault feature extraction ability and end-to-end fault diagnosis ***,utilizing the respective advantages of convolution neural network(CNN)and Transformer in local and global feature extraction,research on cooperating the two have demonstrated promise in the field of fault ***,the cross-channel convolution mechanism in CNN and the self-attention calculations in Transformer contribute to excessive complexity in the cooperative *** complexity results in high computational costs and limited industrial *** tackle the above challenges,this paper proposes a lightweight CNN-Transformer named as SEFormer for rotating machinery fault ***,a separable multiscale depthwise convolution block is designed to extract and integrate multiscale feature information from different channel dimensions of vibration ***,an efficient self-attention block is developed to capture critical fine-grained features of the signal from a global ***,experimental results on the planetary gearbox dataset and themotor roller bearing dataset prove that the proposed framework can balance the advantages of robustness,generalization and lightweight compared to recent state-of-the-art fault diagnosis models based on CNN and *** study presents a feasible strategy for developing a lightweight rotating machinery fault diagnosis framework aimed at economical deployment.

关键词： CNN-Transformer separable multiscale depthwise convolution efficient self-attention fault diagnosis

Merging polymers of intrinsic microporosity and porous carbon-based zinc oxide composites in novel mixed matrix membranes for efficient gas separation

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Green Energy & Environment 2025年第1期10卷 203-213页

作者： Muning Chen Jiemei Zhou Jing Ma Weigang Zheng Guanying Dong Xin Li Zhihong Tian Yatao Zhang Jing Wang Yong Wang School of Chemical Engineering Zhengzhou UniversityZhengzhou450001HenanChina state Key Laboratory of Materials-Oriented Chemical Engineering and College of Chemical Engineering Nanjing Tech UniversityNanjing211816JiangsuChina Singapore Membrane Technology Centre Nanyang Environment and Water Research InstituteNanyang Technological UniversitySingapore637141Singapore Engineering Research Center for Nanomaterials Henan UniversityKaifeng475004HenanChina state Key Laboratory of Coking Coal Resources Green Exploitation Zhengzhou UniversityZhengzhou 450001China School of Energy and Environment Southeast UniversityNanjing210096JiangsuChina

Mixed matrix membranes(MMMs)have demonstrated significant promise in energy-intensive gas separations by amalgamating the unique properties of fillers with the facile processability of ***,achieving a simultaneous enhancement of permeability and selectivity remains a formidable challenge,due to the difficulty of achieving an optimal match between polymers and *** this study,we incorporate a porous carbon-based zinc oxide composite(C@ZnO)into high-permeability polymers of intrinsic microporosity(PIMs)to fabricate *** dipole–dipole interaction between C@ZnO and PIMs ensures their exceptional compatibility,mitigating the formation of non-selective voids in the resulting ***,C@ZnO with abundant interconnected pores can provide additional low-resistance pathways for gas transport in *** a result,the CO_(2) permeability of the optimized C@ZnO/PIM-1 MMMs is elevated to 13,215 barrer,while the CO_(2)/N_(2) and CO_(2)/CH4 selectivity reached 21.5 and 14.4,respectively,substantially surpassing the 2008 Robeson upper ***,molecular simulation results further corroborate that the augmented membrane gas selectivity is attributed to the superior CO_(2) affinity of C@*** summary,we believe that this work not only expands the application of MMMs for gas separation but also heralds a paradigm shift in the application of porous carbon materials.

关键词： Mixed matrix membranes Polymers of intrinsic microporosity CO_(2)separation Porous carbon materials

Impregnating photo-stable gold precursor onto uncalcined TS-1 to boost catalytic hydro-oxidation of propane

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Science China Chemistry 2025年

作者： Zhihua Zhang Erchuan Yang Fan Liu Kesheng Xu Yuxia Zhong Jinwei Sun Shudong Shi Xuezhi Duan Xinggui Zhou state Key Laboratory of Chemical Engineering East China University of Science and Technology

Immobilizing highly dispersed Au nanoparticles onto titanium silicalite-1 (TS-1) by a simple impregnation method under light is still a challenging *** this work,a high photostable Au precursor protected by thiol ligands was firstly synthesized,and the as-prepared Au precursor displayed excellent stability under light for over 30 days,while the Au precursor without thiol ligands formed precipitates after just 2 h under ***,the Au precursor protected by thiol ligands was immobilized on the external surface of uncalcined TS-1 (i.e.,TS-1-B) by the incipient wetness impregnation method (IWI method) to prepare Au/TS-1-B *** activity of as-prepared Au/TS-1-B catalyst in the hydro-oxidation of propane to acetone was 1.4 times higher than that of the catalyst prepared by the deposition-precipitation urea method (DPU method).The structures of the Au/TS-1-B catalysts prepared by different methods were analyzed by multiple *** to the Au/TS-1-B catalyst prepared by the DPU method,the Au/TS-1-B catalyst synthesized by the IWI method exhibited a narrower size distribution of Au nanoparticles and had more small Au particles (<2 nm),which is the main reason for its superior ***,the effects of gold loadings,reaction temperature and Si/Ti molar ratio on the catalytic performance of the Au/TS-1-B catalyst prepared by the IWI method were also *** addition,the Au/TS-1-B catalyst prepared by the IWI method also exhibited excellent stability for over 140 h.

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Rapid and scalable preparation of highly quaternized polymer networks to achieve efficient simultaneous adsorption of iodide and pertechnetate

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Science China Chemistry 2025年第1期68卷 337-349页

作者： Meiyun Xu Song Gu Fulong Chen Zhe Zhao Peng Liu Daoben Hua state Key Laboratory of Radiation Medicine and Protection School of Radiological and Interdisciplinary Sciences (RAD-X) Collaborative Innovation Center of Radiological Medicine of Jiangsu Higher Education Institutions Soochow University

The efficient separation of fission products,such as TcO4-and I-,holds strategic significance for the management of radioactive wastes and environmental *** this study,we propose an ultrafast strategy for scalable preparation of a highly quaternized organic network to facilitate efficient and synchronous separation of iodide and *** network can be prepared within a few minutes at room temperature,using polyethylenimine and 1,2,4,5-tetrakis（bromomethyl）benzene as building *** chlorine replacement,the network,abundantly decorated with quaternary ammonium groups （Cl@QPN）,exhibits an ultrahigh positive charge density of 7.6 mmol/*** enables the rapid and efficient enrichment of target anions through strong electrostatic Coulomb *** a result,Cl@QPN exhibits significantly higher adsorption rate constants of 0.830 g/（mg min） for ReO4-（a nonradioactive surrogate of TcO4-） and 0.677 g/（mg min） for I-compared to other ***,it possesses high adsorption capacities,reaching 1,681 mg/g for ReO4-and 917.4 mg/g for I-.Cl@QPN also demonstrates good selectivity towards target ions and shows efficient adsorption for99TcO4-.Additionally,Cl@QPN exhibits high dynamic processing capacities,handling up to 3,100 and 7,400 kg of simulated streams per kilogram of material for I-and ReO4-,respectively.

关键词： quaternized polymer networks adsorption pertechnetate iodide liquid radioactive streams

Research progress of catalysts for direct coal liquefaction

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Journal of Energy Chemistry 2025年第1期100卷 481-497页

作者： Wei Song Penggao Liu Xinyue Chen Ting Wang Chunrong He Rui Hao Kaiyu Liu state Key Laboratory of Chemistry and Utilization of Carbon Based Energy Resources College of Chemistry Xinjiang University College of Chemistry and Chemical Engineering Henan Polytechnic University Hunan Provincial Key Laboratory of Chemical Power Sources College of Chemistry and Chemical Engineering Central South University

Coal direct liquefaction technology is a crucial contemporary coal chemical technology for efficient and clean use of coal resources. The development of direct coal liquefaction technology and the promotion of alternative energy sources are important measures to guarantee energy security and economic security. However, several challenges need to be addressed, including low conversion rate, inadequate oil yield, significant coking, demanding reaction conditions, and high energy consumption. Extensive research has been conducted on these issues, but further exploration is required in certain aspects such as pyrolysis of macromolecules during the liquefaction process, hydrogen activation, catalysts' performance and stability, solvent hydrogenation, as well as interactions between free radicals to understand their mechanisms better. This paper presents a comprehensive analysis of the design strategy for efficient catalysts in coal liquefaction, encompassing the mechanism of coal liquefaction, catalyst construction,and enhancement of catalytic conversion efficiency. It serves as a comprehensive guide for further research endeavors. Firstly, it systematically summarizes the conversion mechanism of direct coal liquefaction, provides detailed descriptions of various catalyst design strategies, and especially outlines the catalytic mechanism. Furthermore, it addresses the challenges and prospects associated with constructing efficient catalysts for direct coal liquefaction based on an understanding of their action mechanisms.

关键词： Direct coal liquefaction Catalysts Mechanism of action Solvent hydrogenation