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High-resolution full waveform seismic imaging: Progresses, challenges, and prospects

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Science China Earth Sciences 2025年第2期68卷 315-342页

作者： Dinghui YANG Xingpeng DONG Jiandong HUANG Zhilong FANG Xueyuan HUANG Shaolin liu Mengxue liu Weijuan MENG Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China Institute of Geology China Earthquake AdministrationBeijing 100029China School of Resources and Environment University of Electronic Science and Technology of ChinaChengdu 611731China School of Mathematics and Statistics Beijing Technology and Business UniversityBeijing 100048China National Institute of Natural Hazards Ministry of Emergency Management of ChinaBeijing 100085China

Full waveform inversion(FWI) is a seismic imaging method with a unified mathematical framework based on wave equation constraints. The FWI method can be used to generate a variety of high-resolution seismic parameter models(e.g.,velocity, anisotropy, viscoelasticity, and attenuation), which can facilitate an in-depth understanding of important scientific problems such as the Earth's interior structure and material composition, earthquake preparation and occurrence, and plate motion and dynamic processes. With the development and cross-integration of disciplines such as geophysics, applied mathematics, and computer science, FWI imaging theories and methods not only play a crucial role in revealing the Earth's interior structure, dynamic evolution, and earthquake mechanisms but also show a wide range of application potential in fields such as resource exploration, medical imaging, engineering inspection, carbon dioxide geological sequestration, and earthquake disaster prediction. In this paper, we provide a comprehensive review and analysis of the development of the FWI method,addressing its current challenges, identifying key issues, future directions, and potential research areas in the theory, methodology, and application of high-resolution FWI imaging. We also offer new insights and perspectives to promote advancements of high-resolution FWI research and applications in Earth sciences and other related fields.

关键词： Full waveform inversion High-resolution imaging Interior structure of the Earth Earthquake preparation me-chanism Multidisciplinary integration

Reduction of thermal stratification due to global warming in winter and spring

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Journal of Oceanology and Limnology 2025年第1期43卷 1-15页

作者： Jie liu Jianming DENG Xiangming TANG State Key Laboratory of Lake Science and Environment Nanjing Institute of Geography and LimnologyChinese Academy of SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China School of Geography and Ocean Science Nanjing UniversityNanjing 210023China

Global warming has been reported to enhance thermal stratification and decrease the mixlayer depth(MLD)in waters due to higher surface water temperatures,especially in *** studies were conducted for individual cases or specific *** present,there is a lack of global assessments on the influence of climate warming in different seasons on thermal *** ECMWF Reanalysis v5(ERA5)dataset was used to estimate the variability of water body mixing and its drivers in different seasons and *** indicate that global warming could enhance thermal stratification and decrease the MLD globally in *** speed was the primary driver of MLD changes,followed by ***,ice melt due to global warming enhanced the mixing in icecovered waters in the Northern Hemisphere,and early ice melt led to early *** depth was the primary driver of MLD changes in the Northern Hemisphere due to delayed ice formation and earlier melting,while wind speed was the primary driver in other regions or during ice-free *** enhanced mixing due to earlier ice melt out in late winter and early spring could promote water circulation and nutrient turnover,and replenish dissolved oxygen in deep water,thereby promoting the maximum biomass of cyanobacteria and advance harmful algal blooms.

关键词： global warming mix-layer depth(MLD) thermal stratification ice depth ECMWF Reanalysis v5(ERA5)dataset

Low-cost and fluoride-free synthesis of MFI zeolite nanosheets with enhanced stability for benzene alkylation with ethanol

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Journal of Energy Chemistry 2025年第1期100卷 458-468页

作者： Peng Zhu Cun liu Yiren Yu Guoshu Gao Yumeng Zhao Xiongfu Zhang Guodong liu Guohui Yang State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of TechnologyDalian 116024 State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023LiaoningChina

Zeolite nanosheets with a short b-axis thickness are highly desirable in lots of catalytic reactions due to their reduced diffusion resistance. Nevertheless, conventional synthesis methods usually require expensive structure-directing agents(SDAs), pricey raw materials, and eco-unfriendly fluorine-containing additives. Here, we contributed a cost-effective and fluoride-free synthesis method for synthesizing high-quality MFI zeolite nanosheets through a Silicalite-1(Sil-1) seed suspension and urea cooperative strategy, only with inexpensive colloidal silica as the Si source. Our approach was effective for synthesizing both Sil-1 and aluminum-containing ZSM-5 nanosheets. By optimizing key synthesis parameters,including seed aging time, seed quantity, and urea concentration, we achieved precise control over the crystal face aspect ratio and b-axis thickness. We also revealed a non-classical oriented nanosheet growth mechanism, where Sil-1 seeds induced the formation of quasi-ordered precursor particles, and the(010)crystal planes of these particles facilitated urea adsorption, thereby promoting c-axis-oriented *** obtained ZSM-5 nanosheets exhibited exceptional catalytic performance in the benzene alkylation with ethanol, maintaining stability for over 500 h, which is 5 times longer than traditional ZSM-5 catalysts. Furthermore, large-scale production of ZSM-5 nanosheets was successfully carried out in a 3 L highpressure autoclave, yielding samples consistent with those from laboratory-scale synthesis. This work marks a significant step forward in the sustainable and efficient production of MFI nanosheets using inexpensive and environmentally friendly raw materials, offering the broad applicability in catalysis.

关键词： MFI zeolite ZSM-5 Nanosheets Scale-up synthesis Aromatic alkylation

Linear polyurethanes with excellent comprehensive properties from poly(ethylene carbonate)diol

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Chinese Chemical Letters 2025年第1期36卷 318-321页

作者： Xinyu liu Jialin Yang Zonglin He Jiaoyan Ai Lina Song Baohua liu School of Materials and Energy Guangdong University of TechnologyGuangzhou 510006China

The synthesis of polyurethanes(PUs)from the reaction of low molecular weight poly(ethylene carbonate)diol(PECD)is rarely *** work reports a novel PU with excellent mechanical properties from the solution polymerization of 4,4-diphenylmethane diisocyanate(MDI)with PECD that was derived from the copolymerization of carbon dioxide(CO_(2))and ethylene oxide(EO).The tensile strength,the elongation at break and 300%constant tensile strength of the PECD-PU were up to 66±2 MPa,880%±50%and 13 MPa,respectively,higher than the control PUs from the reaction of MDI with commercial polyethers or *** PECD-PU with high CO_(2) carbonate content exhibited good solvent resistance and chemical *** importance,the mechanical properties and chemical resistance of PECD-PU were significantly enhanced with the increasing content of CO_(2),i.e.,the carbonate unit in *** work provides comprehensive properties of PECD-derived PUs,indicating that PECD is a competitive precursor for the preparation of PU and has broad application prospects.

关键词： Carbon dioxide Poly(ethylene carbonate)diol Polyurethane Ethylene oxide Copolymerization

Removal of arsenic from water by silver nanoparticles and Fe-Ce mixed oxide supported on polymeric anion exchanger

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Journal of Environmental Sciences 2025年第5期151卷 540-549页

作者： Li Li Su-juan Yu Rong-gang Zheng Qing-cun Li Rui liu Jing-fu liu State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China Hubei Key Laboratory of Environmental and Health Effects of Persistent Toxic Substances Institute of Environment and HealthJianghan UniversityWuhan 430056China University of Chinese Academy of Sciences Beijing 100049China Department of Ecology and Resources Engineering He Tao CollegeInner Mongolia 015000China

By encapsulating nanoscale particles of goethite(α-FeO(OH)),hydrous ceric oxide(CeO_(2)·H_(2)O,HCO)and silver nanoparticles(AgNPs)in the pores of polystyrene anion exchanger D201,a novel nanocomposite FeO(OH)-HCO-Ag-D201 was prepared for the effective removal of arsenic from *** isotherm study shows that FeO(OH)-HCO-Ag-D201 has excellent adsorption performance for As(III)and As(V),with an increased adsorption capacity of As(III)to 40.12 mg/g compared to that of 22.03 mg/g by the composite adsorbent without AgNPs(FeO(OH)-HCO-D201).The adsorption kinetics data showed that the sorption rate of FeO(OH)-HCO-Ag-D201 for As(III)is less than that for As(V),and the adsorption of As(III)and As(V)were consistent with the pseudo-second-order model and the pseudofirst-order model,*** or basic conditions are favored for the adsorption of As(III/V)by FeO(OH)-*** with nitrate/chloride/bicarbonate,sulfate/silicate/phosphate showed more remarkable inhibition of arsenic removal by FeO(OH)-HCO-Ag-D201,whereas natural organic matter showed no interference to the arsenic *** As(V)adsorption involved different interactions such as electrostatic attraction and surface complexation,while the adsorption of As(III)involved the part oxidization of As(III)to As(V)and the simultaneous adsorption of As(III)and As(V).In addition to the Ce(IV)in CeO_(2)·H_(2)O acted as an oxidant,the synergistic effect ofα-FeO(OH)and AgNPs also contributed to the oxidization of As(III)to As(V).Moreover,the reusable property suggested that this FeO(OH)-HCO-Ag-D201 nanocomposite has great potential for arsenic-contaminated water purification.

关键词： FeO(OH)-HCO-Ag-D201 Arsenic removal Synergistic effect Oxidation Electrostatic attraction Surface complexation

Mesh-supported V2O5-WO3/TiO2 nanosheet array catalysts for efficient removal of NOx

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Tungsten 2025年第1期7卷 100-111页

作者： Zhi-Qi Zhang liu Yang Wen Luo Vladimir An Jing Li Bao-Dan liu School of Materials Science and Engineering Northeastern University Foshan Graduate School of Innovation Northeastern University Kizhner Research Center School of Advanced Manufacturing Technologies Tomsk Polytechnic University

The design and synthesis of vanadium-based denitration catalysts with low-temperature activity pose significant challenges in the field of toxic gas *** this study,we have developed a novel approach to fabricate highly efficient V2O5-WO3/TiO2monolithic mesh catalysts for NOxreduction at low ***,TiO2nanosheets with strong adhesion and large surface area were grown on Ti mesh using plasma electrolytic oxidation technology and hydrothermal ***,super-small traces of WO3and V2O5active nano-species were subsequently deposited on TiO2nanosheets using the deposition-precipitation *** to traditional ceramic-based V2O5-WO3/TiO2catalysts,our V2O5-WO3/TiO2monolithic mesh catalyst exhibits superior mechanical performance,excellent thermal conductivity,lower pressure drop,higher utilization of active components,and stronger synergistic ***,the V2O5-WO3/TiO2monolithic mesh catalysts exhibited excellent low-temperature catalytic activity with 98% of NOxconversion at 220℃,and remarkable long-term SO2tolerance and water resistance in the selective catalytic reduction（SCR） of NOxwith *** SCR reaction of tiny V2O5and WO3active species supported on TiO2nanosheets directly demonstrated to follow the Eley-Rideal mechanism by in situ infrared spectra.

关键词： Low temperature activity Monolithic mesh catalysts NH3-SCR SO2 tolerance V2O5-WO3/TiO2

Tuning the ion-dipole interactions between fluoro and carbonyl(EC)by electrolyte design for stable lithium metal batteries

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Chinese Chemical Letters 2025年第1期36卷 579-584页

作者： Guihuang Fang Ying liu Yangyang Feng Ying Pan Hongwei Yang Yongchuan liu Maoxiang Wu Faculty of Metallurgy and Energy Engineering Kunming University of Science and TechnologyKunming 650093China Key Laboratory of Optoelectronic Materials Chemistry and Physics Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

Ethylene carbonate(EC)is the conventional and promising solvent to achieve high energy lithium metal ***,the innate low energy level of lowest unoccupied molecular orbital(LUMO)in EC makes it incompatible with lithium metal,causing uncontrolled lithium growth and low Coulombic efficiency(CE).Herein,we introduced bis(2,2,2-trifluoroethyl)carbonate(TFEC),a carbonate with a strong electron-withdrawing effect(-CF_(3)),which enhances the stability of EC at electrode interface by reducing ion-dipole interactions between Li^(+)and *** the interaction between Li and EC weakens,TFEC and more PF_(6)^(-)anions coordinate with Li^(+),promoting the formation of contact ion pairs(CIPs)and aggregates(AGGs),thereby increasing the inorganic composition within the solid electrolyte ***,the distinct solvated sheath structure favors the decomposition of fluorinated solvents and PF_(6)^(-)anions,forming inorganic-rich electrode-electrolyte interfaces(SEI and CEI),thereby ensuring high stability for both the Li anode and high-voltage ***,when applied in the full-cell Li||LiMn_(0.8)Fe_(0.2)PO_(4),it displays consistent cycling performance,exhibiting minimal capacity decay with a retention rate of 62.5%after800 cycles,substantially surpassing that of cells using base electrolytes(29.8%).

关键词： Lithium-ion batteries LiMn_(0.8)Fe_(0.2)PO_(4) High-voltage Solvation structure Ethylene carbonate Bis(2,2,2-trifluoroethyl)carbonate

Down-regulation of SEIPIN transcription attenuated the triacylglycerol accumulation in Nannochloropsis oceanica

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Journal of Oceanology and Limnology 2025年第1期43卷 187-195页

作者： Lixian liu Li GUO Hang liu Xiaohui PAN Yanan ZONG Leili FENG Guanpin YANG College of Marine Life Sciences Ocean University of ChinaQingdao 266003China Institutes of Evolution and Marine Biodiversity Ocean University of ChinaQingdao 266003China Key Laboratory of Marine Genetics and Breeding of Ministry of Education Ocean University of ChinaQingdao 266003China MoE Laboratory of Evolution and Marine Biodiversity Ocean University of ChinaQingdao 266003China

Abnormal content of protein SEIPIN causes Berardinelli-Seip congenital lipodystrophy type 2(BSCL2)in *** studies have shown that Arabidopsis thaliana has evolved three SEIPIN homologs,determining the fusion and size of lipid *** oceanica is a model oleaginous microalga with the accumulation potential of fatty *** believe that the SEIPIN homolog if any in *** should function as it does in humans,plant among *** this study,we identified a homologous gene of SEIPIN in ***,constructed a bacterial plasmid containing the elements controlling the transcription of its complete antisense RNA,and integrated the linearized plasmid into the *** *** obtained a transformant in which the abundance of SEIPIN transcript is significantly *** cytometry analysis showed that the triacylglycerol(TAG)content of the transformant is significantly lower than that of the wild type(WT).Transcriptomic analysis showed that the down-regulation of SEIPIN transcript abundance could affect the protein functioning in endoplasmic reticulum(ER),implying that SEIPIN gene can function in *** in a similar way to that in ***.

关键词： Nannochloropsis oceanica antisense RNA SEIPIN neutral lipid

DIGNN-A:Real-Time Network Intrusion Detection with Integrated Neural Networks Based on Dynamic Graph

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Computers, Materials & Continua 2025年第1期82卷 817-842页

作者： Jizhao liu Minghao Guo College of Computer Zhongyuan University of TechnologyZhengzhou450007China

The increasing popularity of the Internet and the widespread use of information technology have led to a rise in the number and sophistication of network attacks and security *** detection systems are crucial to network security,playing a pivotal role in safeguarding networks from potential ***,in the context of an evolving landscape of sophisticated and elusive attacks,existing intrusion detection methodologies often overlook critical aspects such as changes in network topology over time and interactions between *** address these issues,this paper proposes a real-time network intrusion detection method based on graph neural *** proposedmethod leverages the advantages of graph neural networks and employs a straightforward graph construction method to represent network traffic as dynamic graph-structured ***,a graph convolution operation with a multi-head attention mechanism is utilized to enhance the model’s ability to capture the intricate relationships within the graph structure ***,it uses an integrated graph neural network to address dynamic graphs’structural and topological changes at different time points and the challenges of edge embedding in intrusion detection *** edge classification problem is effectively transformed into node classification by employing a line graph data representation,which facilitates fine-grained intrusion detection tasks on dynamic graph node feature *** efficacy of the proposed method is evaluated using two commonly used intrusion detection datasets,UNSW-NB15 and NF-ToN-IoT-v2,and results are compared with previous studies in this *** experimental results demonstrate that our proposed method achieves 99.3%and 99.96%accuracy on the two datasets,respectively,and outperforms the benchmark model in several evaluation metrics.

关键词： Intrusion detection graph neural networks attention mechanisms line graphs dynamic graph neural networks