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Gray Matter-Based Age Prediction Characterizes Different Regional Patterns
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作者 Nianming Zuo Tianyu Hu +3 位作者 Hao Liu Jing Sui Yong Liu Tianzi Jiang 《Neuroscience Bulletin》 SCIE CAS CSCD 2021年第1期94-98,共5页
Dear Editor,The brain experiences ongoing changes across different ages to support brain development and functional reorganization.During the span of adulthood,although the brain has matured from a neurobiological per... Dear Editor,The brain experiences ongoing changes across different ages to support brain development and functional reorganization.During the span of adulthood,although the brain has matured from a neurobiological perspective,it is still continuously shaped by external factors such as habits,the family setting,socioeconomic status,and the work environment [1].In contrast to chronological age (CA),brain(or biological) age (BA) is conceptualized as an important index for characterizing the aging process and neuropsychological state,as well as individual cognitiveperformance.Growing evidence indicates that BA can be assessed by neuroimaging techniques,including MRI [2]. 展开更多
关键词 Gray Matter-Based Age Prediction characterizes Different Regional Patterns
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Retraction Note to:Gray Matter-Based Age Prediction Characterizes Different Regional Patterns
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作者 Nianming Zuo Tianyu Hu +3 位作者 Hao Liu Jing Sui Yong Liu Tianzi Jiang 《Neuroscience Bulletin》 SCIE CAS CSCD 2023年第6期1037-1037,共1页
The authors have retracted this article.After publication we found an error in the implementation code that resulted in data leakage in the age-prediction model training process.We have redesigned the prediction model... The authors have retracted this article.After publication we found an error in the implementation code that resulted in data leakage in the age-prediction model training process.We have redesigned the prediction model and tested the mode with an extended dataset(around 2000 subjects,in contrast to the 600 subjects in this article). 展开更多
关键词 process. PREDICTION CHARACTER
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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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THE PRINCESS AND THE PEA
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作者 Ruth Devlin 《空中英语教室(初级版.大家说英语)》 2026年第1期12-16,51,56,共7页
Small things can show a person's true character Find lt What was the weather like when the girl came to the castle door?nce upon a time,there was a prince.He wanted to marry a real princess.He traveled all around ... Small things can show a person's true character Find lt What was the weather like when the girl came to the castle door?nce upon a time,there was a prince.He wanted to marry a real princess.He traveled all around the world looking for one. 展开更多
关键词 WEATHER PRINCE PRINCESS true character
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Controllable phase-reconstruction strategy for LiFePO_(4)homogeneous regeneration:Reaction mechanism,characterization and prospect
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作者 Zihao Zeng Yi Chen +4 位作者 Chao Zhu Hai Lei Wei Sun Yue Yang Peng Ge 《Journal of Energy Chemistry》 2026年第1期553-571,I0013,共20页
The growing volume of end-of-life lithium-ion batteries(LIBs)represents both an urgent environmental challenge and a critical resource opportunity,especially for cathode materials.Among commercial cathodes,LiFePO4(LFP... The growing volume of end-of-life lithium-ion batteries(LIBs)represents both an urgent environmental challenge and a critical resource opportunity,especially for cathode materials.Among commercial cathodes,LiFePO4(LFP)dominates the market due to its favorable properties;thus,a substantial amount of LFP cathode materials is expected to retire in the near future.The conventional hydrometallurgical method suffers from high costs and serious pollution.Direct regeneration technologies,especially solid-state sintering,provide a more efficient and environmentally benign alternative by repairing cathode structures through high-temperature solid-phase reactions without extra chemical reagents.Traditional solid-state sintering faces challenges in processing spent LFP from diverse sources,struggling to achieve the homogenization of physical–chemical properties and electrochemical performance.To address the limitations above,phase homogenization with a lattice reconstruction strategy has been investigated,which can enable effective lattice reconstruction and microstructural homogenization,demonstrating robust adaptability to spent samples from variable sources.This review systematically summarizes the mechanisms,detailed steps,characterization techniques,and advances in pre-oxidation optimization(including ion-doping and coated carbon layer modification),as well as future research directions for sustainable LFP recycling.Given this,this review is expected to offer theoretical guidance for achieving homogeneous regeneration of LFP cathode. 展开更多
关键词 Spent LiFePO_(4) REGENERATION Phase-reconstruction Reaction mechanism CHARACTERIZATION
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A Cloud-Based Distributed System for Story Visualization Using Stable Diffusion
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作者 Chuang-Chieh Lin Yung-Shen Huang Shih-Yeh Chen 《Computers, Materials & Continua》 2026年第2期1751-1769,共19页
With the rapid development of generative artificial intelligence(GenAI),the task of story visualization,which transforms natural language narratives into coherent and consistent image sequences,has attracted growing r... With the rapid development of generative artificial intelligence(GenAI),the task of story visualization,which transforms natural language narratives into coherent and consistent image sequences,has attracted growing research attention.However,existing methods still face limitations in balancing multi-frame character consistency and generation efficiency,which restricts their feasibility for large-scale practical applications.To address this issue,this study proposes a modular cloud-based distributed system built on Stable Diffusion.By separating the character generation and story generation processes,and integratingmulti-feature control techniques,a cachingmechanism,and an asynchronous task queue architecture,the system enhances generation efficiency and scalability.The experimental design includes both automated and human evaluations of character consistency,performance testing,and multinode simulation.The results show that the proposed system outperforms the baseline model StoryGen in both CLIP-I and human evaluation metrics.In terms of performance,under the experimental environment of this study,dual-node deployment reduces average waiting time by approximately 19%,while the four-node simulation further reduces it by up to 65%.Overall,this study demonstrates the advantages of cloud-distributed GenAI in maintaining character consistency and reducing generation latency,highlighting its potential value inmulti-user collaborative story visualization applications. 展开更多
关键词 Stable diffusion story visualization generativeAI distributed computing cloud-based system character consistency
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Integrative identification of Aphelenchoides fragariae(Nematoda:Aphelenchoididae) parasitizing Fuchsia×hybrida in China
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作者 Qiuling Huang Yan Liao +6 位作者 Chunhui Huang Huan Peng Lingchiu Tsang Borong Lin Deliang Peng Jinling Liao Kan Zhuo 《Journal of Integrative Agriculture》 2026年第2期769-774,共6页
The strawberry crimp nematode(Aphelenchoides fragariae) is a serious pathogen of ornamental crops and a significant quarantine concern in approximately 50 countries and regions,including China.A nematode population be... The strawberry crimp nematode(Aphelenchoides fragariae) is a serious pathogen of ornamental crops and a significant quarantine concern in approximately 50 countries and regions,including China.A nematode population belonging to the genus Aphelenchoides was isolated from symptomatic leaves of fuchsia plants(Fuchsia×hybrida Hort.ex Sieb.& Voss.) in Chengdu,Sichuan Province,China.Morphological and morphometric characteristics were determined using light microscopy and scanning electron microscopy.Detailed examination revealed diagnostic features consistent with A.fragariae.Three ribosomal DNA(rDNA) regions,i.e.,partial small subunit(SSU) rRNA,D2-D3 expansion segments of the large subunit(LSU) rRNA,and the internal transcribed spacer(ITS),were amplified and sequenced.Bayesian phylogenetic analyses based on these sequences placed the isolate in a well-supported monophyletic clade with reference A.fragariae specimens,clearly separated from other Aphelenchoides species.Furthermore,host-suitability assays demonstrated that this nematode population not only infects and reproduces on Fuchsia×hybrida,but also on Fragaria ananassa and Pteris vittata,two known hosts of A.fragariae.Collectively,morphological,molecular,and host-range evidence confirm the identification of this nematode as A.fragariae.To our knowledge,this represents the first molecular and morphological confirmation of A.fragariae in China,and the first report of Fuchsia×hybrida as a natural host for this species. 展开更多
关键词 strawberry crimp nematode morphology molecular characterization host-suitability test fuchsia
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Effect of Tannin and Nanocellulose on Properties of Sustainable Cellulose Acetate Films
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作者 JoséMarcelo Faria de Queiroz Júnior Nathália Ramosde Melo +2 位作者 Ulisses Oliveira Costa Letícia Vitorazi Flavia Lega Braghiroli 《Journal of Renewable Materials》 2026年第2期144-170,共27页
The development of sustainable materials has encouraged the use of biopolymers as alternatives to synthetic polymers.Polymeric films have stood out for their high potential in environmentally sustainable applications.... The development of sustainable materials has encouraged the use of biopolymers as alternatives to synthetic polymers.Polymeric films have stood out for their high potential in environmentally sustainable applications.Conventional cellulose acetate(CA)-based films are attractive due to their biodegradability and film-forming ability.However,their functional performance often requires enhancement through the incorporation of additives.In this context,two bio-based additives were investigated:condensed tannin(0%,5%and 10%wt.),a natural polyphenol known for its antioxidant and antimicrobial properties,and nanocrystalline cellulose(CNC)(0%,0.5%and 1%wt.),which act as reinforcing agents to improve mechanical strength and barrier properties.The results showed that tannin generally enhanced mechanical strength and surface uniformity while imparting contact-based antimicrobial activity.CNC reduced water uptake and improved thermal stability,but when used alone,it tended to lower mechanical performance and increase surface roughness.The combination of CNC and tannin produced performance shifts that depended strongly on their relative concentrations,with no consistent synergistic effect across all properties.In certain balanced ratios,CNC benefited fromtannin’smatrix-stabilizing effect,leading to improved strength or reduced moisture absorption.Antimicrobial activity in acetic acid–based films was linked to residual acidity,whereas in acetonebased films,tannin alone was responsible for the antimicrobial effect by contact.These findings highlight that the physicochemical,mechanical,and functional performance of CA films(CAFs)is governed not only by additive type but also by the precise interplay between CNC and tannin,underscoring the need for formulation strategies tailored to the requirements of specific applications. 展开更多
关键词 Cellulose derivatives crystalline nanocellulose condensed tannin biobased films CHARACTERIZATION
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Quantitative calibration method for the evolution of mechanical properties of gas-containing coal under mining-induced stress and microscopic failure evaluation
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作者 Zeqi Wang Liang Yuan +2 位作者 Bin Hu Bo Li Laisheng Huang 《International Journal of Mining Science and Technology》 2026年第3期475-497,共23页
Current quantitative characterization methods for the mechanical response and damage evolution of coal seams at different burial depths under mining-induced stress remains insufficient.To address this,this study estab... Current quantitative characterization methods for the mechanical response and damage evolution of coal seams at different burial depths under mining-induced stress remains insufficient.To address this,this study establishes a quantitative characterization model for the evolution of mechanical properties in gas-bearing coal masses at varying burial depths.It innovatively introduces a dual damage quantification technique and develops a coupled damage evolution model that comprehensively considers energy evolution,effective mining-induced stress,permeability,and a damage sensitivity coefficient,followed by extensive analysis.Key findings include:coal damage exhibits heterogeneous evolutionary characteristics under mining-induced stress;based on the theory of irreversible deformation,the proposed damage characterization equation can effectively determine the critical damage threshold of coal;the three-parameter EXP function model is more suitable for characterizing the time-dependent damage process of coal under mining-induced stress;a new characterization method for the coal brittleness evaluation index is proposed,revealing an 800 m burial depth boundary for the coal brittleness index;at the microscopic level,achieving quantitative characterization of the correlation between peak stress and the average reduction in functional groups during mining-induced failure of coal at different burial depths.Finally,the mapping relationship between laboratory experimental parameters and field monitoring indicators for early warning of coal mine dynamic disasters is established. 展开更多
关键词 Mining-induced stress Coupled damage Quantitative characterization Energy evolution
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Coupled Effects of Single-Vacancy Defect Positions on the Mechanical Properties and Electronic Structure of Aluminum Crystals
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作者 Binchang Ma Xinhai Yu Gang Huang 《Computers, Materials & Continua》 2026年第1期332-352,共21页
Vacancy defects,as fundamental disruptions in metallic lattices,play an important role in shaping the mechanical and electronic properties of aluminum crystals.However,the influence of vacancy position under coupled t... Vacancy defects,as fundamental disruptions in metallic lattices,play an important role in shaping the mechanical and electronic properties of aluminum crystals.However,the influence of vacancy position under coupled thermomechanical fields remains insufficiently understood.In this study,transmission and scanning electron microscopy were employed to observe dislocation structures and grain boundary heterogeneities in processed aluminum alloys,suggesting stress concentrations and microstructural inhomogeneities associated with vacancy accumulation.To complement these observations,first-principles calculations and molecular dynamics simulations were conducted for seven single-vacancy configurations in face-centered cubic aluminum.The stress response,total energy,density of states(DOS),and differential charge density were examined under varying compressive strain(ε=0–0.1)and temperature(0–600 K).The results indicate that face-centered vacancies tend to reduce mechanical strength and perturb electronic states near the Fermi level,whereas corner and edge vacancies appear to have weaker effects.Elevated temperatures may partially restore electronic uniformity through thermal excitation.Overall,these findings suggest that vacancy position exerts a critical but position-dependent influence on coupled structure-property relationships,offering theoretical insights and preliminary experimental support for defect-engineered aluminum alloy design. 展开更多
关键词 Aluminum crystal vacancy defect microstructural characterization stress response electronic structure thermomechanical coupling
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Research on characterization methods for track irregularities
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作者 Lifeng Xin Lei Xu +3 位作者 Jiaxin Zhang Menglin Pei Jianfeng Mao Dangxiong Wang 《Railway Engineering Science》 2026年第1期25-39,共15页
The characterization of track irregularities is crucial in railway dynamics,as track irregularities are the primary source of internal excitation in railway systems.In this paper,three mathematical models are proposed... The characterization of track irregularities is crucial in railway dynamics,as track irregularities are the primary source of internal excitation in railway systems.In this paper,three mathematical models are proposed to characterize the track irregularities under different circumstances.The first model is a novel explicit track spectrum function,which performs better in reflecting the inherent periodic components of track irregularities than the existing track spectra.On this foundation,the second model,a parameterized track spectrum random model,is proposed to represent the vast measured track irregularities from the probabilistic perspective.Finally,the third model,an imprecise track spectrum interval model based on a neighborhood uniform sampling Bootstrap method,is presented to identify the confidential interval of the track spectra when the track irregularity data are limited.Three examples are illustrated to demonstrate the feasibility of the three track irregularity models in characterizing the track irregularities in different conditions.This research can help capture the railway deformation status and optimize track maintenance strategies. 展开更多
关键词 RAILWAY Track irregularity Power spectral density CHARACTERIZATION Random model Imprecise track spectrum
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A comprehensive review on oxygen vacancies modified catalysts:Synthesis,characterization,and crucial role in catalytic ozonation
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作者 Fengchen Wang Yujia Xiang +9 位作者 Yuqi Zhang Xin Zhou Jing Zhang Chuanshu He Heng Zhang Zhaokun Xiong Peng Zhou Hongyu Zhou Yang Liu Bo Lai 《Chinese Chemical Letters》 2026年第2期253-262,共10页
Among various advanced oxidation processes(AOPs),heterogeneous catalytic ozonation has garnered extensive attention in wastewater treatment owing to its broad pH range applicability and the elimination of the need for... Among various advanced oxidation processes(AOPs),heterogeneous catalytic ozonation has garnered extensive attention in wastewater treatment owing to its broad pH range applicability and the elimination of the need for additional energy input.Enhancing catalyst activity by introducing oxygen vacancies has been used extensively in heterogeneous catalytic ozonation.This paper reviews prevalent methods for the construction and characterization of oxygen vacancies.Based on a thorough examination of existing research,the role of oxygen vacancies is categorized according to their primary mechanisms of action in heterogeneous catalytic ozonation.For example,modulation of the catalyst electronic structure to enhance electron transfer;participation in the reaction as an active site to generate radicals and non-radicals;and exposure of more metal sites to enhance the reaction.Lastly,the paper delineates the limitations and future research directions concerning the role of oxygen vacancies in catalytic ozonation.This review addresses the gap in existing literature concerning the role of oxygen vacancies in catalytic ozone systems,establishes a comprehensive theoretical framework to aid in the design of efficient ozone catalysts,and delves into the functionality of oxygen vacancies in heterogeneous catalytic ozone reactions. 展开更多
关键词 Catalytic ozonation Bulk defects Surface defects Oxygen vacancies Degradation mechanism Synthesis and characterization
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Corrosion fatigue mechanisms and control technologies in aviation aluminum alloys:A critical review
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作者 Yuqiang CHEN Zimin HE +5 位作者 Heng LI Dingding LU Yufeng SONG Lihua ZHAN Suping PAN Wenhui LIU 《Chinese Journal of Aeronautics》 2026年第2期531-563,共33页
Aviation aluminum alloys,primarily from the Al-Cu,Al-Zn-Mg-(Cu),and Al-Li series,have been widely applied over six decades,greatly advancing the aviation industry.However,their Corrosion Fatigue(CF)properties impede f... Aviation aluminum alloys,primarily from the Al-Cu,Al-Zn-Mg-(Cu),and Al-Li series,have been widely applied over six decades,greatly advancing the aviation industry.However,their Corrosion Fatigue(CF)properties impede further advancements,prompting extensive research into their CF behaviors and underlying mechanisms.This review comprehensively evaluates previous studies on their development history,CF mechanisms,and key influencing factors.First,the historical evolution of aerospace aluminum alloys is summarized.Then,the currently recognized four crack initiation mechanisms and three crack propagation mechanisms are concluded,and the effects of external and internal factors on CF performance are discussed.The paper also reviews three methods and CF life prediction models for characterizing the CF behavior of aerospace aluminum alloys.Most existing studies on the CF behavior of aluminum alloys are based on the single corrosive environment,neglecting the fact that aircrafts experience multiple corrosive environments during service.However,the most critical scientific challenge is how to enhance their CF properties under increasingly demanding service conditions.For the purpose,this paper introduces advanced forming techniques based on the microstructural control,such as Equal Channel Angular Pressing(ECAP)and High-Pressure Torsion(HPT),aimed at laying the theoretical foundation for improving CF properties through microstructural regulation. 展开更多
关键词 Aviation aluminum alloys CF characterization Corrosion fatigue Forming technologies Influencing factors Life prediction models
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Operando characterization of the internal multi-fields of industrial-scale fuel cells and mechanistic insight
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作者 Weichen Ji Xin Cai +3 位作者 Yunyang Ma Xin Liu Andreas Friedrich Rui Lin 《Journal of Energy Chemistry》 2026年第3期667-675,共9页
Despite significant progress in fuel cell technology,its large-scale industrial application is still challenged by the frequently encountered performance failure during long-term operation.Clarifying the failure mecha... Despite significant progress in fuel cell technology,its large-scale industrial application is still challenged by the frequently encountered performance failure during long-term operation.Clarifying the failure mechanism is the key to extending the lifecycle and enhancing stability.Herein,we have developed a time and space resolved multi-field characterization,including electrochemical impedance spectroscopy,to unveil its underlying mechanism.With this operando and non-destructive characterization,the dynamic evolution of the internal mass transport,heat,and electricity field distribution is fully depicted within an industrial-scale fuel cell in operation.Thus,it is revealed that hydrogen starvation occurs in the outlet region due to the excessive hydrogen consumption during the loading-down process.This can induce local low current density and carbon corrosion,which may subsequently cause severe damage to the structure of the catalyst layer and membrane,ultimately leading to performance failure.With this understanding,we further identify a descriptor for early diagnosis to prevent any potential degradation.The methodology is of significance,which can bring fuel cell technology a step further towards industrial applications. 展开更多
关键词 Operando characterization Internal multi-fields Industrial-scale fuel cell Local Electrochemical impedance spectroscopy Stability mechanism
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In‑Operando X‑Ray Imaging for Sobering Examination of Aqueous Zinc Metal Batteries
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作者 Yuhang Dai Hongzhen He +4 位作者 Mengzheng Ouyang Jianuo Chen Jie Lin Haobo Dong Guanjie He 《Nano-Micro Letters》 2026年第3期330-337,共8页
Aqueous zinc metal batteries(AZMBs)face significant challenges in achieving reversibility and cycling stability,primarily due to hydrogen evolution reactions(HER)and zinc dendrite growth.In this study,by employing car... Aqueous zinc metal batteries(AZMBs)face significant challenges in achieving reversibility and cycling stability,primarily due to hydrogen evolution reactions(HER)and zinc dendrite growth.In this study,by employing carefully designed cells that approximate the structural characteristics of practical batteries,we revisit this widely held view through in-operando X-ray radiography to examine zinc dendrite formation and HER under nearpractical operating conditions.While conventional understanding emphasizes the severity of these processes,our findings suggest that zinc dendrites and HER are noticeably less pronounced in dense,real-operation configurations compared to modified cells,possibly due to a more uniform electric field and the suppression of triple-phase boundaries.This study indicates that other components,such as degradation at the cathode current collector interface and configuration mismatches within the full cell,may also represent important barriers to the practical application of AZMBs,particularly during the early stages of electrodeposition. 展开更多
关键词 Aqueous Zn metal batteries X-ray imaging In situ characterization Degradation mechanism
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High-frequency emphasized neural network reconstruction method for in situ synchrotron radiation ultrafast computed tomography characterization
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作者 Jing-Wei Li Yu Xiao +3 位作者 Yong-Cun Li Xiao-Fang Hu Guo-Hao Du Feng Xu 《Nuclear Science and Techniques》 2026年第3期5-17,共13页
There is a contradiction between the evolution rate of materials and the time resolution of SR-CT characterization in the in situ synchrotron radiation computed tomography(SR-CT)characterization of ultrafast evolution... There is a contradiction between the evolution rate of materials and the time resolution of SR-CT characterization in the in situ synchrotron radiation computed tomography(SR-CT)characterization of ultrafast evolution process.The sampling strategy of the ultra-sparse angle is an effective method for improving time resolution.Accurate reconstruction under sparse sampling conditions has always been a bottleneck problem.In recent years,convolutional neural networks have shown outstanding advantages in sparse-angle CT reconstruction given the development of deep learning.However,existing ideas did not consider the expression of high-frequency details in neural networks,limiting their application in accurate SR-CT characterization.A novel high-frequency information-constrained deep learning network(HFIC-Net)is proposed in response to this problem.Additional high-frequency information constraints are added to improve the accuracy of the reconstruction results.Further,a series of numerical reconstruction experiments are conducted to verify this new method,and the results indicate that the reconstruction results of HFIC-Net method effectively improve reconstruction quality.This new method uses only eight-angle projections to achieve the reconstruction effect of the filtered backprojection method(FBP)method in 360 projections.The results of the HFIC-Net method demonstrate clear boundaries and accurate detailed structures,correcting the misinformation caused by using other methods.For quantitative evaluation,the SSIM used to evaluate image structure similarity is increased from 0.1951,0.9212,and 0.9308 for FBP,FBP-Conv,and DDC-Net,respectively,to 0.9620 for HFIC-Net.Finally,the results of actual SR-CT experimental data indicate that the new method can suppress artifacts and achieve accurate reconstruction,and it is suitable for the in situ SR-CT accurate characterization of ultxafast evolution process. 展开更多
关键词 Accurate SR-CT characterization CT reconstruction Sparse-angle CT reconstruction problem High-frequency information constrained Deep learning
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Insights into the geranylgeranyl pyrophosphate synthase(GGPPS)gene family in Osmanthus fragrans and the role of OfGGPPS13 in the formation of floral color and aroma
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作者 Hanruo Qiu Qingyin Tian +4 位作者 Guimin Zeng Chenchen Xie Xiulian Yang Lianggui Wang Yuanzheng Yue 《Journal of Integrative Agriculture》 2026年第1期138-149,共12页
Osmanthus fragrans is most famous for its strong aroma,and different varieties have different degrees of fragrance and color.Fragrance and color are important factors affecting the ornamental quality of O.fragrans.Ter... Osmanthus fragrans is most famous for its strong aroma,and different varieties have different degrees of fragrance and color.Fragrance and color are important factors affecting the ornamental quality of O.fragrans.Terpenoids are important secondary metabolites in plants,with β-carotene(C40)being the major pigment substance and linalool(C10)being the key aromatic component in O.fragrans.The geranylgeranyl pyrophosphate synthase genes(GGPPSs)play important roles in secondary metabolism in plants.However,the functions of the GGPPS family in floral color and fragrance formation has rarely been reported in O.fragrans.In this study,24 Of GGPPS genes were identified and classified into two subfamilies.The Of GGPPSs showed tissue-specific expression and Of GGPPS13 had highest expression in flowers.The Of GGPPS13 protein was localized to chloroplasts.The transcriptome data of Of GGPPS13 was verified by q RT-PCR and the expression level in‘Wanyingui'with strong aroma was higher than that in‘Zhuangyuanhong'with deep color at different flower development stages.Transient overexpression of Of GGPPS13 in O.fragrans petals showed that Of GGPPS13 increased the β-carotene content,the main color substance of O.fragrans,but decreased the linalool content,the main volatile organic compound(VOC)in the floral aroma of O.fragrans.Of GGPPS13 was indicated as the critical gene related to terpenoid synthesis in the floral aroma and color formation in O.fragrans.Our findings provide gene resources on the GGPPS gene family for further revealing the molecular regulation mechanism of the floral color and aroma formation in O.fragrans. 展开更多
关键词 GGPPS gene family Osmanthus fragrans oral color and aroma formation functional characterization
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Hypervelocity impact response and protection for the track steels of rocket sled system via light-gas gun experiments
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作者 Siwei Zhao Yi Zeng +5 位作者 Xuewen Zhou Weixing Zhao Botao Xie Jianbin Jing Yan Chen Yilun Liu 《Defence Technology(防务技术)》 2026年第2期282-293,共12页
Hypervelocity rocket sled systems are critical for testing advanced military technologies,yet track damage at speeds exceeding Mach 5 remains a significant challenge for system reliability and performance.In this stud... Hypervelocity rocket sled systems are critical for testing advanced military technologies,yet track damage at speeds exceeding Mach 5 remains a significant challenge for system reliability and performance.In this study,we investigated the hypervelocity impact response and protection for highstrength U71 Mn or bainitic steel used in rocket sled tracks.Flyer plate impact experiments using a two-stage light-gas gun were conducted to study the hypervelocity collision response,followed by the microstructural characterization via optical microscope,scanning electron microscopy equipped with electron backscatter diffraction to reveal underlying damage mechanisms.Then,the calibrated thermalmechanical coupled finite element simulations using the Johnson-Cook constitutive model and MieGrüneisen equation of state were carried out.Results indicated that bainitic steel exhibits superior impact resistance with predominantly smooth scratch-dominated damage due to its higher ductility.In contrast,U71 Mn suffered significant material spallation and crack propagation arising from brittle fracture mechanisms.Zinc-rich epoxy primer coatings effectively mitigated stress concentration and temperature rise in the substrate at impacting velocities below 2.4 km/s,so as to suppress the microstructural damage such as adiabatic shear bands and dynamic recrystallization.However,coating protection diminished at ultra-high-speed impacts due to the coating failure.Dimensional analysis established quantitative relationships of the gouge damage size to projectile mass,impact velocity,and material yield strength.This study provides in-depth insights into damage mechanisms in hypervelocity rail systems,demonstrating that bainitic steel combined with protective coatings can significantly enhance impact resistance and system reliability,offering valuable guidance for the design and optimization of hypervelocity testing platforms. 展开更多
关键词 Hypervelocity rocket sled Gouge of the track steels Two-stage light-gas gun Microstructural characterization Coating protection
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A perspective review of applications of the computed tomography(CT)scan imaging technique for microscopic reservoir rock characterization
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作者 Achinta Bera Bharadwaj Shukla Dhruvikkumar Jogani 《Deep Underground Science and Engineering》 2026年第1期4-27,共24页
In hospitals,a medical computed tomography(CT)scan is used to detect damage to infected areas of the human body.Using this technology,scientists and engineers have found a way to detect the internal pore connections a... In hospitals,a medical computed tomography(CT)scan is used to detect damage to infected areas of the human body.Using this technology,scientists and engineers have found a way to detect the internal pore connections and characterize rock samples of oil and gas reservoirs in the petroleum industry.Nowadays,the micro-CT scan technique is gaining considerable interest in reservoir rock characterization and in situ monitoring of fluid flow through porous media during different flooding experiments.Along with this digital rock physics(DRP)idea,images have been used to accurately describe and model for simulations of rock samples.In this review,the application of micro-CT and medical-CT scanning in the oil and gas industry has been thoroughly discussed.Recent improvements in DRP and modern imaging techniques in the oil and gas industry have been modeled using both experimental and simulation work.The combination of a DRP study and a CT scan has also been discussed as a unique idea for the current scenario of research work in this field.The available literature shows that the modern imaging technique and the DRP concept can enable an understanding of the pore network model.It has also been observed that the visualization of fluid flow behavior through porous media is now possible during fluid movement through the core samples.This review contributes to the new research area and aids those in this field in quickly gaining an understanding of applied image techniques in the oil and gas industry. 展开更多
关键词 computed tomography scanning technology digital rock physics multiphase flow oil and gas industry porous media reservoir characterization
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The Newly Discovered Pathway for Oxygen Evolution Reaction: In-Situ/Operando Characterization Techniques for Catalyst Development
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作者 Rabia Khalid Muhammad Tahir +2 位作者 Muhammad Umar Pin Fang Yujing Li 《Carbon Energy》 2026年第3期12-40,共29页
Water electrolysis is pivotal for converting renewable energy into clean hydrogen fuel,addressing global energy demand sustainably.However,the development of highly efficient and cost-effective catalysts for the oxyge... Water electrolysis is pivotal for converting renewable energy into clean hydrogen fuel,addressing global energy demand sustainably.However,the development of highly efficient and cost-effective catalysts for the oxygen evolution reaction(OER)remains a significant challenge,particularly at the industrial scale.This report explores a newly discovered pathway,the oxide path mechanism(OPM) for OER-mechanism involving the oxide formation and evolution during the reaction,emphasizing its potential to overcome existing limitations.OPM enables direct O-O coupling without oxygen vacancies,offering superior stability.We detail both classical and innovative in-situ characterization techniques that are central to unraveling the OER mechanism.The advanced in-situ electrochemical techniques,such as inductively coupled plasma mass spectroscopy,X-ray photoelectron spectroscopy,and Mössbauer spectroscopy,coupled with in-situ structural analyses,provide crucial insights into the catalyst surface,the electrode-electrolyte interface and the kinetics of OER.This review provides a systematic analysis integrating classical electrochemical methods with advanced in-situ/operando techniques,specifically focusing on understanding OPM.While numerous studies have examined individual characterization methods,this study systematically integrates traditional electrochemical approaches with in-situ and operando techniques,offering critical insights into their complementary roles in elucidating reaction pathways.The integration of these methodologies provides unprecedented understanding of catalyst behavior under operational conditions,guiding the rational design of next-generation OER catalysts.Furthermore,we discuss essential standardized test toolkits and protocols,such as those for rotating disk electrode and membrane electrode assembly,which are vital for ensuring reproducibility and scalability in OER catalyst research. 展开更多
关键词 in-situ characterization techniques mechanistic understanding OER catalyst operando spectroscopy oxygen evolution reaction(OER) renewable energy water splitting
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