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Crystal structure,thermal analysis,and luminescence properties of six heterocyclic lanthanide complexes
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作者 SONG Zihe ZHAO Jinjin +1 位作者 REN Ning ZHANG Jianjun 《无机化学学报》 北大核心 2026年第1期181-192,共12页
Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'... Six new lanthanide complexes:[Ln(3,4-DEOBA)3(4,4'-DM-2,2'-bipy)]2·2C_(2)H_(5)OH,[Ln=Dy(1),Eu(2),Tb(3),Sm(4),Ho(5),Gd(6);3,4-DEOBA-=3,4-diethoxybenzoate,4,4'-DM-2,2'-bipy=4,4'-dimethyl-2,2'-bipyridine]were successfully synthesized by the volatilization of the solution at room temperature.The crystal structures of six complexes were determined by single-crystal X-ray diffraction technology.The results showed that the complexes all have a binuclear structure,and the structures contain free ethanol molecules.Moreover,the coordination number of the central metal of each structural unit is eight.Adjacent structural units interact with each other through hydrogen bonds and further expand to form 1D chain-like and 2D planar structures.After conducting a systematic study on the luminescence properties of complexes 1-4,their emission and excitation spectra were obtained.Experimental results indicated that the fluorescence lifetimes of complexes 2 and 3 were 0.807 and 0.845 ms,respectively.The emission spectral data of complexes 1-4 were imported into the CIE chromaticity coordinate system,and their corre sponding luminescent regions cover the yellow light,red light,green light,and orange-red light bands,respectively.Within the temperature range of 299.15-1300 K,the thermal decomposition processes of the six complexes were comprehensively analyzed by using TG-DSC/FTIR/MS technology.The hypothesis of the gradual loss of ligand groups during the decomposition process was verified by detecting the escaped gas,3D infrared spectroscopy,and ion fragment information detected by mass spectrometry.The specific decomposition path is as follows:firstly,free ethanol molecules and neutral ligands are removed,and finally,acidic ligands are released;the final product is the corresponding metal oxide.CCDC:2430420,1;2430422,2;2430419,3;2430424,4;2430421,5;2430423,6. 展开更多
关键词 lanthanide complexes fluorescence property crystal structure thermal analysis
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Discovery of a Novel Ginseng Polysaccharide:Structure Characterization,in vitro Fermentability and Anti-oxidative Mechanism of Fermented Product via the Nrf2/HO-1 Pathway on Aβ-induced-PC 12 Cells
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作者 DONG Binbin HOU Zong +3 位作者 ZHENG Zhong XING Junpeng LIU Zhiqiang LIU Shu 《高等学校化学学报》 北大核心 2026年第1期173-189,共17页
In this study,a novel polysaccharide GPA-G 2-H was derived from ginseng.Furthermore,the coherent study of its structural characteristics,fermented characteristics in vitro,as well as antioxidant mechanism of fermented... In this study,a novel polysaccharide GPA-G 2-H was derived from ginseng.Furthermore,the coherent study of its structural characteristics,fermented characteristics in vitro,as well as antioxidant mechanism of fermented product FGPA-G 2-H on Aβ25-35-induced PC 12 cells were explored.The structure of GPA-G 2-H was determined by means of zeta potential analysis,FTIR,HPLC,XRD,GC-MS and NMR.The backbone of GPA-G 2-H was mainly composed of→4)-α-D-Glcp-(1→with branches substituted at O-3.Notably,GPA-G 2-H was degraded by intestinal microbiota in vitro with total sugar content and pH value decreasing,and short-chain fatty acids(SCFAs)increasing.Moreover,GPA-G 2-H significantly promoted the proliferation of Lactobacillus,Muribaculaceae and Weissella,thereby making positive alterations in intestinal microbiota composition.Additionally,FGPA-G 2-H activated the Nrf 2/HO-1 signaling pathway,enhanced HO-1,NQO 1,SOD and GSH-Px,while inhabited Keap 1,MDA and LDH,which alleviated Aβ-induced oxidative stress in PC 12 cells.These provide a solid theoretical basis for the further development of ginseng polysaccharides as functional food and antioxidant drugs. 展开更多
关键词 Ginseng polysaccharide structural characterization Intestinal microbiota FERMENTABILITY Oxidative stress
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Energy absorption characteristics of additively manufactured sea sponge-inspired lattice structures under low-velocity impact loading
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作者 J Jefferson Andrew Jabir Ubaid +4 位作者 Mohammed Ayaz Uddin Omar Waqas Saadi Kamran Ahmed Khan Rehan Umer Andreas Schiffer 《Defence Technology(防务技术)》 2026年第1期118-129,共12页
Low-velocity impact tests are carried out to explore the energy absorption characteristics of bio-inspired lattices,mimicking the architecture of the marine sponge organism Euplectella aspergillum.These sea sponge-ins... Low-velocity impact tests are carried out to explore the energy absorption characteristics of bio-inspired lattices,mimicking the architecture of the marine sponge organism Euplectella aspergillum.These sea sponge-inspired lattice structures feature a square-grid 2D lattice with double diagonal bracings and are additively manufactured via digital light processing(DLP).The collapse strength and energy absorption capacity of sea sponge lattice structures are evaluated under various impact conditions and are compared to those of their constituent square-grid and double diagonal lattices.This study demonstrates that sea sponge lattices can achieve an 11-fold increase in energy absorption compared to the square-grid lattice,due to the stabilizing effect of the double diagonal bracings prompting the structure to collapse layer-bylayer under impact.By adjusting the thickness ratio in the sea sponge lattice,up to 76.7%increment in energy absorption is attained.It is also shown that sea-sponge lattices outperform well-established energy-absorbing materials of equal weight,such as hexagonal honeycombs,confirming their significant potential for impact mitigation.Additionally,this research highlights the enhancements in energy absorption achieved by adding a small amount(0.015 phr)of Multi-Walled Carbon Nanotubes(MWCNTs)to the photocurable resin,thus unlocking new possibilities for the design of innovative lightweight structures with multifunctional attributes. 展开更多
关键词 Sea sponge-inspired lattice structures Additive manufacturing Energy absorption Low-velocity impact Lattice structure NANOCOMPOSITE
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Mechanism of enhancing NH_(3)-SCR performance of Mn-Ce/AC catalyst by the structure regulation of activated carbon with calcite in coal
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作者 NIU Jian LI Yuhang +4 位作者 BAI Baofeng WEN Chaolu LI Linbo ZHANG Huirong GUO Shaoqing 《燃料化学学报(中英文)》 北大核心 2026年第1期69-79,共11页
To elucidate the effect of calcite-regulated activated carbon(AC)structure on low-temperature denitrification performance of SCR catalysts,this work prepared a series of Mn-Ce/De-AC-xCaCO_(3)(x is the calcite content ... To elucidate the effect of calcite-regulated activated carbon(AC)structure on low-temperature denitrification performance of SCR catalysts,this work prepared a series of Mn-Ce/De-AC-xCaCO_(3)(x is the calcite content in coal)catalysts were prepared by the incipient wetness impregnation method,followed by acid washing to remove calcium-containing minerals.Comprehensive characterization and low-temperature denitrification tests revealed that calcite-induced structural modulation of coal-derived AC significantly enhances catalytic activity.Specifically,NO conversion increased from 88.3%of Mn-Ce/De-AC to 91.7%of Mn-Ce/De-AC-1CaCO_(3)(210℃).The improved SCR denitrification activity results from the enhancement of physicochemical properties including higher Mn^(4+)content and Ce^(4+)/Ce^(3+)ratio,an abundance of chemisorbed oxygen and acidic sites,which could strengthen the SCR reaction pathways(richer NH_(3)activated species and bidentate nitrate active species).Therefore,NO removal is enhanced. 展开更多
关键词 CALCITE activated carbon structure Mn-Ce/AC catalyst NH_(3)-SCR performance
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Development of the vertebral column and fin support structures in Encrasicholina punctifer larvae and juveniles
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作者 PASSMORE Roland Madziva WANG Xiaodong +1 位作者 DU Zhipeng ZHONG Junsheng 《水产学报》 北大核心 2026年第2期145-158,共14页
Anchovies are key forage species in coastal and pelagic food webs,playing crucial ecological and commercial roles in marine ecosystems.Encrasicholina punctifer is a commercially and ecologically important species,yet ... Anchovies are key forage species in coastal and pelagic food webs,playing crucial ecological and commercial roles in marine ecosystems.Encrasicholina punctifer is a commercially and ecologically important species,yet little is known about its osteological development characteristics.Understanding these ontogenetic patterns is essential for explaining phylogenetic relationships within Clupeiformes,informing larval identification in ichthyoplankton surveys,and enhancing aquaculture practices.This study describes the ontogenetic characteristics of the appendicular and median skeletons and fin supports in E.punctifer larvae and juveniles,providing quantitative ontogenetic timelines to address gaps in engraulid developmental biology and contribute to teleost ontogeny research.Larval and juvenile specimens of E.punctifer;size range:3.00-34.56 mm standard length(SL)and notochord length(NL)collected from the Philippine Sea were processed using the standard Alizarin red and Alcian blue clearing-and-staining technique to differentiate ossified and cartilaginous elements.Specimens were examined under a stereo microscope and imaged with an HTC1600ISP digital camera for detailed morphological analysis of skeletal structures.Caudal complex development was evident by 5.55 mm NL,with the initial appearance of cartilaginous hypurals 1–2 and parhypural,followed by Hy3–5 at 6.08 mm NL.Cartilaginous Hy6 was visible by 9.58 mm SL in postflexion larvae.Six hypural bones were present from the postflexion to juvenile stage.Principal fin rays formed via intramembranous ossification at 6.32 mm NL,and segmentation was evident by 10.24 mm SL.Neural arch 1 appeared at 7.38 mm NL,preceding full haemal arch development.Uroneurals 1–2 and ural centra ossified by 9.58 mm SL,with Hy5 detached from U1 at 10.24 mm SL.Preural centra ossified before the arches.Epurals 1 and 2 were evident by 10.24 mm SL.Dorsal fin proximal radials developed anteriorly and distal radials posteriorly.Pectoral fin development initiated with an ossified cleithrum and the coracoscapular cartilage at 5.25 mm NL.By 10.24 mm SL,cartilaginous neural and haemal arches and spines were distinct.Uroneural 1 initially develops as cartilage.The formation of a pleurostyle aligns with clupeoid fish skeletal ontogeny.Dorsal and anal fin development follows a distinctive pattern,with variability in fin support development.Our results reveal accelerated caudal complex formation in E.punctifer and contribute new knowledge on the osteological characteristics of the genus Encrasicholina,and aid in understanding larval and juvenile ontogeny of marine teleosts. 展开更多
关键词 Encrasicholina punctifer skeletal structures ONTOGENY larvae and juveniles staining and clearing of cartilage and bone
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Synthesis and crystal structures of Co(Ⅱ)/Cu(Ⅱ)coordination polymers based on solvent and ligand concentration regulation strategy
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作者 SUN Yinxia LIU Liping +7 位作者 BAI Xue SUN Yu SUN Wanhong DENG Zhepeng CHEN Jianghai WANG Jianjun XU Li ZHANG Shuzhen 《无机化学学报》 北大核心 2026年第2期340-354,共15页
Four distinct coordination polymers(CPs)were successfully synthesized by altering solvent types and adjusting ligand concentrations,and their crystal structures were investigated.[Co(L)(FDCA)(H_(2)O)_(2)]·0.5H_(2... Four distinct coordination polymers(CPs)were successfully synthesized by altering solvent types and adjusting ligand concentrations,and their crystal structures were investigated.[Co(L)(FDCA)(H_(2)O)_(2)]·0.5H_(2)O(1)was synthesized as a 2D structure using Coas the metal source,methanol‑water(4∶6,V/V)as the solvent,and specific concentrations of 2,5‑furandicarboxylic acid(H_(2)FDCA)and 1,3,5‑triimidazole benzene(L).Adjusting to pure water and lowering the concentration of L yielded the 1D chain structure of[Co(HL)2(H_(2)O)_(2)](FDCA)_(2)·6H_(2)O(2).Using Cu(Ⅱ)as the metal source,methanol/water(9∶1,V/V)as the solvent,and specific concentrations of L and H2FDCA,the 1D chain structure of[Cu(L)(FDCA)(H_(2)O)]·2H_(2)O(3)was synthesized.Upon increasing the concentrations of L and H2FDCA,and switching the solvent to pure water,the 1D chain structure of[Cu(HL)_(2)(H_(2)O)_(2)](FDCA)_(2)·6H_(2)O(4)was obtained.This shows that changing the solvent and ligand concentrations can affect the structural changes of CPs.In addition,the solid‑state photoluminescence of CPs 1‑4 at room temperature was studied,and their morphological changes were observed via scanning electron microscopy.Density functional theory calculations revealed that the negative charge concentrates on the O and N atoms of the ligand,facilitating ligand‑metal ion coordination.CCDC:2403934,1;2403935,2;2403936,3;2403938,4. 展开更多
关键词 Co(Ⅱ)/Cu(Ⅱ)coordination polymer crystal structure solvent system ligand concentration regulation strategy
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Determining the Effect of Grain Size on the Microstructure and Oxidation of Nuclear Graphite
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作者 Xu Qiao Xinlei Cao +6 位作者 Yuying Zhang Wei Chen Chunzhen Yang Zhengcao Li Xing Zhou Ke Shen Zhou Zhou 《Carbon Energy》 2026年第1期138-152,共15页
Fine-grained nuclear graphite is a key material in high-temperature gas-cooled reactors(HTGRs).During air ingress accidents,core graphite components undergo severe oxidation,threatening structural integrity.Therefore,... Fine-grained nuclear graphite is a key material in high-temperature gas-cooled reactors(HTGRs).During air ingress accidents,core graphite components undergo severe oxidation,threatening structural integrity.Therefore,understanding the oxidation behavior of nuclear graphite is essential for reactor safety.The influence of oxidation involves multiple factors,including temperature,sample size,oxidant,impurities,filler type and size,etc.The size of the filler particles plays a crucial role in this study.Five ultrafine-and superfine-grained nuclear graphite samples(5.9-34.4μm)are manufactured using identical raw materials and manufacturing processes.Isothermal oxidation tests conducted at 650℃-750℃ are used to study the oxidation behavior.Additionally,comprehensive characterization is performed to analyze the crystal structure,surface morphology,and nanoscale to microscale pore structure of the samples.Results indicate that oxidation behavior cannot be predicted solely based on filler grain size.Reactive site concentration,characterized by active surface area,dominates the chemical reaction kinetics,whereas pore tortuosity,quantified by the structural parameterΨ,plays a key role in regulating oxidant diffusion.These findings clarify the dual role of microstructure in oxidation mechanisms and establish a theoretical and experimental basis for the design of high-performance nuclear graphite capable of long-term service in high-temperature gas-cooled reactors. 展开更多
关键词 DIFFUSION nuclear graphite OXIDATION pore structure reaction rate
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Dynamic characteristics and vibration isolation performance of an integrated kangaroo bio-inspired vibration suppression structure
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作者 Shihua Zhou Zichun Zhou +3 位作者 Xinhai Yu Chenhui Zhou Pengyang Wang Zhaohui Ren 《Acta Mechanica Sinica》 2026年第1期276-291,共16页
Inspired that kangaroo can buffer the impact and absorb vibration from the ground and keep the whole-body stable,an integrated kangaroo bio-inspired vibration suppression(IKBVS)structure considering vibration isolatio... Inspired that kangaroo can buffer the impact and absorb vibration from the ground and keep the whole-body stable,an integrated kangaroo bio-inspired vibration suppression(IKBVS)structure considering vibration isolation-absorption simultaneously is proposed for low/wide band frequency vibration control.Based on skeleton mass,articulation friction,and the synergistic action among skeleton,articulation,and muscle/tendon,a vibration suppression model with more biological basic characteristics is derived.The validity of model and method is confirmed,and the static and dynamic analysis of the IKBVS system is carried out to investigate the vibration suppression performance.The quasi-zero stiffness region can be achieved with a smaller initial installation angle,medium rod length,smaller foot stiffness,and slightly lighter isolated mass in a wide displacement interval.The coupling mechanism of vibration isolation-absorption is revealed by parameter analysis.The results indicate that the IKBVS structure has favorite dynamic properties due to adjustable nonlinearity,namely,lower and adjustable resonance and anti-resonance frequency/peak and different levels of vibration suppression effect in high-frequency range are achieved readily.This research provides new insight into application of bio-inspired vibration suppression structures in various engineering systems for better vibration control. 展开更多
关键词 IKBVS structure Vibration isolation-absorption Vibration transmission Quasi-zero stiffness
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Rationally designed nickel-cobalt oxide/sulfide heterostructure for high-performance oxygen evolution reaction and anion exchange membrane water electrolysis
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作者 Hyeonji Kwon Hyeongseok Seo +3 位作者 Siyeon Kang Sang Eun Shim Kyeongseok Min Sung-Hyeon Baeck 《Journal of Energy Chemistry》 2026年第1期955-966,I0021,共13页
To realize the practical application of anion exchange membrane water electrolysis(AEMWE),it is essential to develop highly active,durable,and cost-effective electrocatalyst for oxygen evolution reaction(OER).Herein,w... To realize the practical application of anion exchange membrane water electrolysis(AEMWE),it is essential to develop highly active,durable,and cost-effective electrocatalyst for oxygen evolution reaction(OER).Herein,we report a hollow-structured Ni_(x)Co_(1−x)O/Ni_(3)S_(2)/Co_(9)S_(8)heterostructure synthesized via sequential template-assisted growth,thermal oxidation,and controlled sulfidation process.The abundant bimetallic heterointerfaces not only provide additional active sites but also promote electronic modulation via charge redistribution.Additionally,the porous and hollow architecture enhances active surface area and mass transfer ability,thereby increasing the number of accessible active sites for alkaline OER.As a result,the prepared electrocatalyst achieves low overpotential of 310 mV at 10 mA cm^(−2)and small Tafel slope of 55.94 mV dec^(−1),demonstrating the exceptional electrocatalytic performance for alkaline OER.When integrated as the anode in an AEMWE cell,it delivers outstanding performance with only 1.657 V at 1.0 A cm^(−2)and reaches high current density of 5.0 A cm^(−2)at 1.989 V,surpassing those of commercial RuO_(2).The cell also shows excellent long-term durability over 100 h with minimal degradation.This study highlights the strong potential of rationally engineered oxide/sulfide heterostructures for next-generation alkaline water electrolysis. 展开更多
关键词 AEMWE Oxygen evolution reaction Transition metal HETEROINTERFACE Hollow structure
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Inverse design framework of hybrid honeycomb structure with high impact resistance based on active learning
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作者 Xingyu Shen Ke Yan +5 位作者 Difeng Zhu Hao Wu Shijun Luo Shaobo Qi Mengqi Yuan Xinming Qian 《Defence Technology(防务技术)》 2026年第1期407-421,共15页
In this study,an inverse design framework was established to find lightweight honeycomb structures(HCSs)with high impact resistance.The hybrid HCS,composed of re-entrant(RE)and elliptical annular re-entrant(EARE)honey... In this study,an inverse design framework was established to find lightweight honeycomb structures(HCSs)with high impact resistance.The hybrid HCS,composed of re-entrant(RE)and elliptical annular re-entrant(EARE)honeycomb cells,was created by constructing arrangement matrices to achieve structural lightweight.The machine learning(ML)framework consisted of a neural network(NN)forward regression model for predicting impact resistance and a multi-objective optimization algorithm for generating high-performance designs.The surrogate of the local design space was initially realized by establishing the NN in the small sample dataset,and the active learning strategy was used to continuously extended the local optimal design until the model converged in the global space.The results indicated that the active learning strategy significantly improved the inference capability of the NN model in unknown design domains.By guiding the iteration direction of the optimization algorithm,lightweight designs with high impact resistance were identified.The energy absorption capacity of the optimal design reached 94.98%of the EARE honeycomb,while the initial peak stress and mass decreased by 28.85%and 19.91%,respectively.Furthermore,Shapley Additive Explanations(SHAP)for global explanation of the NN indicated a strong correlation between the arrangement mode of HCS and its impact resistance.By reducing the stiffness of the cells at the top boundary of the structure,the initial impact damage sustained by the structure can be significantly improved.Overall,this study proposed a general lightweight design method for array structures under impact loads,which is beneficial for the widespread application of honeycomb-based protective structures. 展开更多
关键词 Re-entrant honeycomb Hybrid structures Inverse design Impact resistance LIGHTWEIGHT
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Multivariate Data Anomaly Detection Based on Graph Structure Learning
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作者 Haoxiang Wen Zhaoyang Wang +2 位作者 Zhonglin Ye Haixing Zhao Maosong Sun 《Computer Modeling in Engineering & Sciences》 2026年第1期1174-1206,共33页
Multivariate anomaly detection plays a critical role in maintaining the stable operation of information systems.However,in existing research,multivariate data are often influenced by various factors during the data co... Multivariate anomaly detection plays a critical role in maintaining the stable operation of information systems.However,in existing research,multivariate data are often influenced by various factors during the data collection process,resulting in temporal misalignment or displacement.Due to these factors,the node representations carry substantial noise,which reduces the adaptability of the multivariate coupled network structure and subsequently degrades anomaly detection performance.Accordingly,this study proposes a novel multivariate anomaly detection model grounded in graph structure learning.Firstly,a recommendation strategy is employed to identify strongly coupled variable pairs,which are then used to construct a recommendation-driven multivariate coupling network.Secondly,a multi-channel graph encoding layer is used to dynamically optimize the structural properties of the multivariate coupling network,while a multi-head attention mechanism enhances the spatial characteristics of the multivariate data.Finally,unsupervised anomaly detection is conducted using a dynamic threshold selection algorithm.Experimental results demonstrate that effectively integrating the structural and spatial features of multivariate data significantly mitigates anomalies caused by temporal dependency misalignment. 展开更多
关键词 Multivariate data anomaly detection graph structure learning coupled network
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Effects of SiO_(2)/Al_(2)O_(3)Ratios on Microstructure,Properties and Elastic Modulus of SiO_(2)-Al_(2)O_(3)-CaO-MgO Alkali-Free Glass
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作者 DONG Peng TENG Zhou +3 位作者 XIE Jun ZHANG Jihong XIONG Dehua CHEN Dequan 《Journal of Wuhan University of Technology(Materials Science)》 2026年第1期45-53,共9页
Alkali-free SiO_(2)-Al_(2)O_(3)-CaO-MgO with different SiO_(2)/Al_(2)O_(3)mass ratios was prepared by conventional melt quenching method.The glass network structure,thermodynamic properties and elastic modulus changes... Alkali-free SiO_(2)-Al_(2)O_(3)-CaO-MgO with different SiO_(2)/Al_(2)O_(3)mass ratios was prepared by conventional melt quenching method.The glass network structure,thermodynamic properties and elastic modulus changes with SiO_(2)and Al_(2)O_(3)ratios were investigated using various techniques.It is found that when SiO_(2)is replaced by Al_(2)O_(3),the Q^(4) to Q^(3) transition of silicon-oxygen network decreases while the aluminum-oxygen network increases,which result in the transformation of Si-O-Si bonds to Si-O-Al bonds and an increase in glass network connectivity even though the intermolecular bond strength decreases.The glass transition temperature(T_(g))increases continuously,while the thermal expansion coefficient increases and high-temperature viscosity first decreases and then increases.Meanwhile,the elastic modulus values increase from 93 to 102 GPa.This indicates that the elastic modulus is mainly affected by packing factor and dissociation energy,and elements with higher packing factors and dissociation energies supplant those with lower values,resulting in increased rigidity within the glass. 展开更多
关键词 alkali free glass glass network structure VISCOSITY elastic modulus
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Additive Manufacturing of Functionally Graded Lattice Structures for Personalized Below-Knee Prosthetic Dampers
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作者 Guy O'Keefe Naser A.Alsaleh +3 位作者 Mahmoud A.El-Sayed A.Jiménez Sabbah Ataya Khamis Essa 《Chinese Journal of Polymer Science》 2026年第1期173-188,I0014,共17页
Functionally graded cellular structures(FGCSs)have a multitude of applications to a wide range of industries.Utilising the ever-progressing technology of additive manufacturing(AM),FGCSs can be applied to control mate... Functionally graded cellular structures(FGCSs)have a multitude of applications to a wide range of industries.Utilising the ever-progressing technology of additive manufacturing(AM),FGCSs can be applied to control material grading and achieve the desired mechanical properties.The current study explores the design and optimisation of FGCSs for AM,with a focus on improving the compression and impact performance of below knee(BK)prosthetic limbs made of thermoplastic polyurethane(TPU).A multiscale research methodology integrating topology optimization(TO),finite element analysis(FEA),and design of experiments(Do E)was adopted to optimise lattice structures in terms of stiffness and lightweight properties.Two-unit cell designs were considered in the study:Schwarz P gyroid and body-centered cubic(BCC).Response surface methodology(RSM)was implemented to analyse the effect of minimum and maximum cell wall thickness,cell size,and unit cell type on the mechanical performance of TPU FGCS structures.The results indicated that a Schwarz P FGCS structure with cell size,minimum and maximum cell wall thickness of 6,0.9 and 2.8 mm,respectively,could be optimal for a compromise between performance and weight.In this optimized case,stiffness and volume fraction values of 684 N/mm and 0.64 were obtained,respectively.The study also presents a proof-of-concept design for a BK prosthetic damper,highlighting the potential of FGCSs to enhance patient comfort,reduce manufacturing costs,and enable personalised designs through 3D scanning and AM.The obtained results could be a step forward towards the incorporation of AM technologies in prosthetics,offering a pathway to lightweight,cost-effective,and functionally tailored solutions. 展开更多
关键词 Additive manufacturing Functionally graded cellular structures Topology optimization PROSTHETICS
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Deterioration and Pore Structure Evolution of GO Modified Polymer Cement Mortar under Salt-freeze-thaw Coupling Effects
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作者 ZHAO Xinyuan WEI Zhiqiang +3 位作者 QIAO Hongxia LI Shaofei CAO Hui XI Lingling 《Journal of Wuhan University of Technology(Materials Science)》 2026年第1期234-246,共13页
To investigate the pore structure of graphene oxide modified polymer cement mortar(GOPM)under salt-freeze-thaw(SFT)coupling effects and its impact on deterioration,this study modifies polymer cement mortar(EMCM)with g... To investigate the pore structure of graphene oxide modified polymer cement mortar(GOPM)under salt-freeze-thaw(SFT)coupling effects and its impact on deterioration,this study modifies polymer cement mortar(EMCM)with graphene oxide(GO).The micro-pore structure of GOPM is characterized using LF-NMR and SEM.Fractal theory is applied to calculate the fractal dimension of pore volume,and the deterioration patterns are analyzed based on the evolution characteristics of capillary pores.The experimental results indicate that,after 25 salt-freeze-thaw cycles(SFTc),SO2-4 ions penetrate the matrix,generating corrosion products that fill existing pores and enhance the compactness of the specimen.As the number of cycles increases,the ongoing formation and expansion of corrosion products within the matrix,combined with persistent freezing forces,and result in the degradation of the pore structure.Therefore,the mass loss rate(MLR)of the specimens shows a trend of first decreasing and then increasing,while the relative dynamic elastic modulus(RDEM)initially increases and then decreases.Compared to the PC group specimens,the G3PM group specimens show a 28.71% reduction in MLR and a 31.42% increase in RDEM after 150 SFTc.The fractal dimensions of the transition pores,capillary pores,and macropores in the G3PM specimens first increase and then decrease as the number of SFTc increases.Among them,the capillary pores show the highest correlation with MLR and RDEM,with correlation coefficients of 0.97438 and 0.98555,respectively. 展开更多
关键词 graphene oxide polymer cement mortar pore structure fractal dimension
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Deflagration fracturing modification of nanoporous structure in the shale reservoirs of the Longmaxi Formation,Southern Sichuan,China
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作者 Yuhang Zhang Shangbin Chen +4 位作者 Yixuan Peng Wei Lin Xinyu Yang Ni Pan Yang Wang Wei Ju 《Natural Gas Industry B》 2026年第1期30-43,共14页
Methane in-situ deflagration fracturing in shale is a revolutionary anhydrous technology.This paper selects shale samples from the Longmaxi Formation in Southern Sichuan to conduct deflagration fracturing tests with p... Methane in-situ deflagration fracturing in shale is a revolutionary anhydrous technology.This paper selects shale samples from the Longmaxi Formation in Southern Sichuan to conduct deflagration fracturing tests with pressures ranging from 25 MPa to 91 MPa.Pore structure changes were experimentally measured to explore the modification differences of nanoscale pore characteristics under varying deflagration pressures.The results show that within the deflagration pressure range examined in this study,(1)Deflagration fracturing can alter the pore volume and specific surface area but does not affect the distribution characteristics of the pore size's peak position.The maximum increments of total pore volume occur at a pressure of 45 MPa.(2)When the deflagration pressure is less than 45 MPa,porosity gradually increases with rising deflagration pressure.When it is greater than 45 MPa,the porosity does not change significantly.With increasing deflagration pressure,it gradually increases:from nanopores,such as mesopores and macropores,to large pores and microcracks.(3)At the low deflagration pressure stage,under the influence of high temperature,slippage pores gradually increase,which is conducive to gas desorption and diffusion migration.As pressure increases,the impact of the explosion shock wave gradually increases,the volume of seepage pores increases significantly,and seepage dominates the migration mode. 展开更多
关键词 Methane in-situ deflagration fracturing Shale gas Nanopore structure Gas migration
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Achieving Ah-Level Zn-MnO_(2)Pouch Cells via Interfacial Solvation Structure Engineering
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作者 Jing Wei Lichao Tan +11 位作者 Qianyi Ma Xintao Long Shibin Li Yu Shi Rui Gao Zijing Xu Dan Luo Jie Zhang Dagang Li Xin Wang Aiping Yu Zhongwei Chen 《Nano-Micro Letters》 2026年第4期526-539,共14页
Aqueous zinc-ion batteries(AZIBs)offer a safe,cost-effective,and high-capacity energy storage solution,yet their performance is hindered by interfacial challenges at the Zn anode,including hydrogen evolution,corrosion... Aqueous zinc-ion batteries(AZIBs)offer a safe,cost-effective,and high-capacity energy storage solution,yet their performance is hindered by interfacial challenges at the Zn anode,including hydrogen evolution,corrosion,and dendritic Zn growth.While most studies focus on regulating Zn~(2+)solvation structures in bulk electrolytes,the evolution of interfacial solvation—where Zn~(2+)undergoes desolvation and deposition—remains insufficiently explored.Here,we introduce sulfated nanocellulose(SNC),an anion-rich biopolymer,to tailor the interfacial solvation structure without altering the bulk electrolyte composition.Using in situ attenuated total reflection Fourier transform infrared spectroscopy and fluorescence interface-extended X-ray absorption fine structure,we reveal that SNC facilitates the formation of a low-coordinated Zn~(2+)solvation shell at the interface by weakening H_(2)O coordination.This transformation is driven by electrostatic interactions between Zn~(2+)and anchored sulfate groups,thereby reducing water activity,improving interfacial stability during charge/discharge,and suppressing parasitic reactions.Consequently,a high average coulombic efficiency of 99.6%over 500 cycles in Zn|Ti asymmetric cells and 1.5 Ah pouch cells(13.4 mg cm^(-2)loading,remained stable over 250 cycles)were achieved in SNC-induced AZIBs.This work underscores the importance of interfacial solvation structure engineering—beyond traditional bulk electrolyte design—in enabling practical,high-performance AZIBs. 展开更多
关键词 Aqueous zinc-ion batteries In situ spectroscopy Interfacial solvation structure NANOCELLULOSE
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Electric-Field-Driven Generative Nanoimprinting for Tilted Metasurface Nanostructures
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作者 Yu Fan Chunhui Wang +6 位作者 Hongmiao Tian Xiaoming Chen Ben QLi Zhaomin Wang Xiangming Li Xiaoliang Chen Jinyou Shao 《Nano-Micro Letters》 2026年第1期290-305,共16页
Tilted metasurface nanostructures,with excellent physical properties and enormous application potential,pose an urgent need for manufacturing methods.Here,electric-field-driven generative-nanoimprinting technique is p... Tilted metasurface nanostructures,with excellent physical properties and enormous application potential,pose an urgent need for manufacturing methods.Here,electric-field-driven generative-nanoimprinting technique is proposed.The electric field applied between the template and the substrate drives the contact,tilting,filling,and holding processes.By accurately controlling the introduced included angle between the flexible template and the substrate,tilted nanostructures with a controllable angle are imprinted onto the substrate,although they are vertical on the template.By flexibly adjusting the electric field intensity and the included angle,large-area uniform-tilted,gradient-tilted,and high-angle-tilted nanostructures are fabricated.In contrast to traditional replication,the morphology of the nanoimprinting structure is extended to customized control.This work provides a cost-effective,efficient,and versatile technology for the fabrication of various large-area tilted metasurface structures.As an illustration,a tilted nanograting with a high coupling efficiency is fabricated and integrated into augmented reality displays,demonstrating superior imaging quality. 展开更多
关键词 Generative nanoimprinting Electric field assistance Tilted metasurface structures Large-area fabrication
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The nature of the Kumkol Basin,northern margin of Qinghai-Xizang Plateau constraints from seismic velocity structure
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作者 Yuan Gao Lun Li +3 位作者 Zhanwu Lu Xiaoyu Guo Linfeng Zhao Shixian Dong 《Earthquake Science》 2026年第1期65-85,共21页
The Kumkol Basin,situated in the northern margin of the Qinghai-Xizang Plateau,provides a unique window into understanding the dynamic mechanisms driving the plateau’s northern expansion.However,its formation and tec... The Kumkol Basin,situated in the northern margin of the Qinghai-Xizang Plateau,provides a unique window into understanding the dynamic mechanisms driving the plateau’s northern expansion.However,its formation and tectonic evolution remain poorly understood due to limited geophysical data in this region.In this study,we computed cross-correlations for the TT components of station-pairs with high signal-to-noise ratios to extract Love wave waveforms and further performed Lovewave ambient noise tomography to image the upper crustal shear-wave velocity structure of the Kumkol basin down to 10 km depth.Our seismic velocity model reveals that the Kumkol Basin has a sedimentary thickness exceeding 8 km,with its center located near the Arka Mountain on the southern side.This suggests that the basin was likely formed as a foreland basin in response to the uplift of the Qiman Tagh Mountain to the north.Additionally,integrated with seismic reflection data,our seismic velocity model images a detachment fault at the basin basement depth.We inferred that the Kumkol Anticlinorium at the basin’s center have been produced by multiple thrust faults converging into this detachment fault at 8–10 km depth following the Early to Middle Miocene uplift of the Qiman Tagh Mountain.This structural configuration indicates pulsed basinward deformation since the late Miocene,likely reflecting a tectonic regime shift from extrusion to distributed shortening in the northern Qinghai-Xizang Plateau.Our findings provide a high-resolution velocity model of the Kumkol Basin,offering critical insights into its structural evolution and supporting future resource exploration in this underexplored region. 展开更多
关键词 Kumkol Basin Qinghai-Xizang Plateau Love wave ambient noise tomography shear-wave structure
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High-resolution 3D shallow crustal structure of Urumqi foreland thrust tectonic belt,northern Tianshan,based on ambient noise tomography
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作者 Xiang Huang Zhengyang Qiang +1 位作者 Weitao Wang Yuan Yao 《Earthquake Science》 2026年第1期86-96,共11页
The Urumqi foreland thrust tectonic belt exhibits complex geological structures and strong seismicity.Imaging its shallow crustal structure is of great significance for understanding its tectonic mechanism and seismog... The Urumqi foreland thrust tectonic belt exhibits complex geological structures and strong seismicity.Imaging its shallow crustal structure is of great significance for understanding its tectonic mechanism and seismogenic environment.We obtained a high-resolution S-wave velocity model of the shallow crust at depths of 0–8 km using ambient noise tomography applied to data from a dense seismic array.Sediments are generally thinner in the southeast and thicker in the northwest,with a maximum thickness of more than 8 km.Variations in the velocity structure near the Xishan,Wanyaogou,and Yamalike faults indicate that their formation was related to differences in the physical properties on either side of the fault.In addition,the faults exhibit thrusting of the low-velocity sides towards the high-velocity sides.In the study area,earthquakes rarely occur at depths of less than 3 km and are mostly concentrated in the high-velocity zone in the southern part.Below 3 km depth,more earthquakes were observed,mainly distributed near faults or in relatively high-velocity areas in the southern part.This suggests that high-velocity structures are more prone to stress accumulation,resulting in earthquakes.At 6–8 km depth,the densely distributed earthquakes in the northwestern part of the Bogda mountains are well-aligned with the northwest-oriented low-velocity zone observed in this study,suggesting that this weak zone likely controls seismicity in this area. 展开更多
关键词 ambient noise tomography shallow crustal structure thrust fault SEISMICITY Urumqi depression
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Nanoreactor-Structured Defective MoS_(2):Suppressing Intercalation-Induced Phase Transitions and Enhancing Reversibility for Potassium-Ion Batteries
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作者 Chunrong Ma Cyrus Koroni +3 位作者 Jiacheng Hu Ji Qian Guangshuai Han Hui Xiong 《Nano-Micro Letters》 2026年第4期771-786,共16页
Conversion-type electrode materials hold significant promise for potassium-ion batteries(PIBs)due to their high theoretical capacities,yet their practical deployment is hindered by sluggish kinetics and irreversible s... Conversion-type electrode materials hold significant promise for potassium-ion batteries(PIBs)due to their high theoretical capacities,yet their practical deployment is hindered by sluggish kinetics and irreversible structural degradation.To overcome these limitations,we propose a rationally engineered nanoreactor architecture that stabilizes defect-rich MoS_(2)via interlayer incorporation of a carbon monolayer,followed by encapsulation within a nitrogen-doped carbon shell,forming a MoSSe@NC heterostructure.This tailored structure synergistically accelerates both K^(+)diffusion kinetics and electron transfer,enabling unprecedented rate performance(107 mAh g^(-1)at 10 Ag^(-1))and ultralong cyclability(86.5%capacity retention after 1200 cycles at 3 A g^(-1)).Mechanistic insights reveal a distinctive“adsorption-conversion”pathway,where sulfur vacancies on exposed S-Mo-S basal planes act as preferential K^(+)adsorption sites,effectively suppressing parasitic phase transitions during intercalation.In situ X-ray diffraction and transmission electron microscopy corroborate the structural reversibility of the conversion reaction,with the carbon matrix dynamically accommodating strain while preserving electrode integrity.This work not only advances the understanding of defect-driven interfacial chemistry in conversion-type materials but also provides a versatile strategy for designing high-performance anodes in next-generation PIBs through heterostructure engineering. 展开更多
关键词 Potassium ion batteries Phase transitions structure reversibility Intercalated heterostructure Defect engineering
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