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Automatic extraction and structuration of soil–environment relationship information from soil survey reports 被引量:9
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作者 WANG De-sheng LIU Jun-zhi +3 位作者 ZHU A-xing WANG Shu ZENG Can-ying MA Tianwu 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第2期328-339,共12页
In addition to soil samples, conventional soil maps, and experienced soil surveyors, text about soils(e.g., soil survey reports) is an important potential data source for extracting soil–environment relationships. Co... In addition to soil samples, conventional soil maps, and experienced soil surveyors, text about soils(e.g., soil survey reports) is an important potential data source for extracting soil–environment relationships. Considering that the words describing soil–environment relationships are often mixed with unrelated words, the first step is to extract the needed words and organize them in a structured way. This paper applies natural language processing(NLP) techniques to automatically extract and structure information from soil survey reports regarding soil–environment relationships. The method includes two steps:(1) construction of a knowledge frame and(2) information extraction using either a rule-based method or a statistic-based method for different types of information. For uniformly written text information, the rule-based approach was used to extract information. These types of variables include slope, elevation, accumulated temperature, annual mean temperature, annual precipitation, and frost-free period. For information contained in text written in diverse styles, the statistic-based method was adopted. These types of variables include landform and parent material. The soil species of China soil survey reports were selected as the experimental dataset. Precision(P), recall(R), and F1-measure(F1) were used to evaluate the performances of the method. For the rule-based method, the P values were 1, the R values were above 92%, and the F1 values were above 96% for all the involved variables. For the method based on the conditional random fields(CRFs), the P, R and F1 values for the parent material were, respectively, 84.15, 83.13, and 83.64%; the values for landform were 88.33, 76.81, and 82.17%, respectively. To explore the impact of text types on the performance of the CRFs-based method, CRFs models were trained and validated separately by the descriptive texts of soil types and typical profiles. For parent material, the maximum F1 value for the descriptive text of soil types was 90.7%, while the maximum F1 value for the descriptive text of soil profiles was only 75%. For landform, the maximum F1 value for the descriptive text of soil types was 85.33%, which was similar to that of the descriptive text of soil profiles(i.e., 85.71%). These results suggest that NLP techniques are effective for the extraction and structuration of soil–environment relationship information from a text data source. 展开更多
关键词 soil–environment relationship TEXT natural LANGUAGE processing extraction structuration
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Accounting Regulation Research and Structuration Theory
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作者 Anthony Moung Yin Chan 《Journal of Modern Accounting and Auditing》 2015年第3期131-137,共7页
This paper considers accounting regulation research from a structuration and cultural perspective. Therefore, accounting regulation research spans over three spheres of enquiry: (1) an accounting focus of standard-... This paper considers accounting regulation research from a structuration and cultural perspective. Therefore, accounting regulation research spans over three spheres of enquiry: (1) an accounting focus of standard-setting; (2) a cultural analysis in an empirical context; and (3) the use of a research methodology drawn from Anthony Giddens' structuration theory. In such approach, accounting regulation research analyzes the accounting regulation actors drawing upon the cultures in their standard-setting actions and interactions, referring to Giddens' three structural properties of meaning, power, and morality. The integration of these three spheres of enquiry is not entirely original. A few prior studies have similar combinations: Although they stress the uses and consequences of accounting systems in producing and reproducing organizational culture and negotiating meaning at the organizational level, this paper chooses the research approach of contextual analysis of accounting systems at more macro-societal and cultural levels. This different research interest and design provides this paper with its distinguishable characteristic from the prior similar studies. 展开更多
关键词 accounting standard-setting accounting and culture structuration analysis accounting regulation
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Application of Structuration Theory and Activity Theory in Enterprise Resources Planning Systems Implementation for Universities
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作者 Clement Mayieko Nyandiere Faustin Kamuzora Ismail Ateya Lukandu 《Computer Technology and Application》 2012年第5期383-392,共10页
An integration of organization culture in the conceptualization and development of Enterprise Resource Planning Systems (ERPs) is critical for an organization to reap potential benefits of the system. In this paper,... An integration of organization culture in the conceptualization and development of Enterprise Resource Planning Systems (ERPs) is critical for an organization to reap potential benefits of the system. In this paper, the authors present an analytical approach through the Structuration Theory: How a university can assess its culture for the purposes of design and development of the ERPs. The authors extend the Structuration Theory by integrating it with the Activity Theory to provide the means of evaluating the activities that the system is to perform. The modified Orlikowski model is applied to depict the relationship between institutional properties, human agents, and technology in the university setup and how this offers a more inclusive approach to ERP systems development and implementation. 展开更多
关键词 structuration theory activity theory information systems ERPs (enterprise resource planning systems) organization culture.
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Cyclic Pulsating Pressure Enhanced Segregating Structuration of Ultra-High Molecular Weight Polyethylene/Graphene Composites as High-performance Light-Weight EMI Shields 被引量:1
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作者 Yun-Zhi Huang Xiao-Xiao Liu +3 位作者 Lan-Wei Li Guang-Ming Huang Zhao-Xia Huang Jin-Ping Qu 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2024年第7期958-967,I0008,共11页
Currently,the enhancement in electromagnetic interference(EMI)performance of polymeric composite generally relies on either improving electrical conductivity(σ)for stronger electromagnetic(EM)reflections or tailoring... Currently,the enhancement in electromagnetic interference(EMI)performance of polymeric composite generally relies on either improving electrical conductivity(σ)for stronger electromagnetic(EM)reflections or tailoring structure for higher EM resonances.Herein,we proposed a novel technique called cyclic pulsating pressure enhanced segregating structuration(CPP-SS),which can reinforce these two factors simultaneously.The structural information was supplied by optical microscopy(OM)and scanning electron microscopy(SEM),both of which confirmed the formation and evolution of segregate structured ultra-high molecular weight polyethylene(UHMWPE)/graphene composites.Then,the result showed that CPP-SS can significantly improve theσof samples.Ultimately,advanced specific EMI shielding efficiency of 31.1 d B/mm was achieved for UHMWPE/graphene composite at 1-mm thickness and a low graphene loading of 5 wt%.Meanwhile,it also confirmed that the intrinsic disadvantage of poor mechanical properties of conventional segregated structure composites can be surpassed.This work is believed to provide a fundamental understanding of the structural and performance evolutions of segregated structured composites prepared under CPPSS,and to bring us a simple and efficient approach for fabricating high-performance,strong and light-weight polymeric EMI shields. 展开更多
关键词 Cyclic pulsating pressure Segregated structure Ultra-high molecular weight polyethylene GRAPHENE Electromagnetic interface
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Diversity and Genetic Structuration of Populations of <i>Plutella xylostella</i>(Lepidoptera, Plutellidae), Cabbage Farming Destroyer in Senegal
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作者 Toffène Diome Mamecor Faye +2 位作者 Marième Seck Cheikh Tidiane Niass Mbacké Sembène 《Advances in Entomology》 2022年第1期1-13,共13页
<div style="text-align:justify;"> <i>Plutella xylostella</i>, pointed out as the most dangerous destroyer of cabbage<span "=""> (<i></i><i><i>Br... <div style="text-align:justify;"> <i>Plutella xylostella</i>, pointed out as the most dangerous destroyer of cabbage<span "=""> (<i></i><i><i>Brassica olerarea</i></i></span>), is a cosmopolitan species. In fact, owing to its large capacity of adaptation, <i></i><i><i>P. xylestella</i></i> colonizes any kind of area. This insect can bring about up to 90% of losses on cabbage farming. To control the insect, Senegalese farmers, very often, resort to high dose of chemical pesticides which are repetitively sprayed. The use of these chemical products gives rise to different varieties of resistant insects, which results in the emergence of different haplotypes between populations. It is in such a context that this study has been undertaken. Our objective is then to contribute to the knowledge of the genetic diversity of <i></i><i><i>P. xylostella</i></i> populations in Senegal. To hit the target, PCR- Sequencing method has been applied on samples from the five following localities: Diofior, Malika, Mboro, Santh Ndong, and Sebikotane. <i></i><i><i>P. xylostella</i></i> from Mboro is genetically different from the other populations. This fact could be due to a different way of using pesticides in this area vis-à-vis of the other localities. On the other hand, between populations of <i></i><i><i>P. xylostella</i></i> from Diofior, Malika, Santh Ndong, and Sebikotane, there is no significant genetic difference. In other respects, phylogenetic trees reveal the existence of two clades: one with individuals from Mboro and the other one with individuals from the other four localities. <i></i><i><i>P. xylostella</i></i> from Mboro distinguishes itself from other populations and then, can be regarded as a sub-population. Thus, the phylogenetic trees reveal the existence of two groups of <i></i><i><i>P. xylostella</i></i> in Senegal. </div> 展开更多
关键词 Brassica oleracea Genetic Diversity Genetic Structure
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New Expansion Dynamics Applied to the Planar Structures of Satellite Galaxies and Space Structuration
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作者 Jacques Fleuret 《Journal of Modern Physics》 2016年第16期2357-2365,共10页
Recent observations of Dwarf Satellite Galaxies (DSG) show that they have a clear tendency to stay in particular planes. Explanations with standard physics remain controversial. Recently, I proposed a new explanation ... Recent observations of Dwarf Satellite Galaxies (DSG) show that they have a clear tendency to stay in particular planes. Explanations with standard physics remain controversial. Recently, I proposed a new explanation of the galactic flat rotation curves, introducing a new cosmic acceleration due to expansion. In this paper, I apply this new acceleration to the dynamics of DSG’s (without dark matter). I show that this new acceleration implies planar structures for the DSG trajectories. More generally, it is shown that this acceleration produces a space structuration around any massive center. It remains a candidate to explain several cosmic observations without dark matter. 展开更多
关键词 Dwarf Satellite Galaxies Dark Matter Expansion Flat Rotation Curves GALAXIES Structure GRAVITATION SYMMETRY
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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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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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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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Hydrothermal conversion from hydrogarnet to hydroandradite based on alumina recovery from red mud
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作者 Hong-fei WU Xiao-lin PAN +3 位作者 Ji-long LIU Feng QIU Tun HE Hai-yan YU 《Transactions of Nonferrous Metals Society of China》 2026年第1期309-322,共14页
To synergistically recover alumina and alkali from red mud(RM),the structural stability and conversion mechanism of hydroandradite(HA)from hydrogarnet(HG)were investigated via the First-principles,XRF,XRD,PSD and SEM ... To synergistically recover alumina and alkali from red mud(RM),the structural stability and conversion mechanism of hydroandradite(HA)from hydrogarnet(HG)were investigated via the First-principles,XRF,XRD,PSD and SEM methods,and a novel hydrothermal process based on the conversion principle was finally proposed.The crystal structure simulation shows that the HA with varied silicon saturation coefficients is more stable than HG,and the HA with a high iron substitution coefficient is more difficult to be converted from HG.The(110)plane of Fe_(2)O_(3) is easier to combine with HG to form HA,and the binding energy is 81.93 kJ/mol.The effects of raw material ratio,solution concentration and hydrothermal parameters on the conversion from HG to HA were revealed,and the optimal conditions for the alumina recovery were obtained.The recovery efficiencies of alumina and Na_(2)O from the RM are 63.06%and 97.34%,respectively,and the Na_(2)O content in the treated RM is only 0.13%. 展开更多
关键词 HYDROGARNET hydroandradite structural stability hydrothermal conversion red mud
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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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Cement-Based Thermoelectric Materials, Devices and Applications
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作者 Wanqiang Li Chunyu Du +1 位作者 Lirong Liang Guangming Chen 《Nano-Micro Letters》 2026年第1期750-781,共32页
Cement stands as a dominant contributor to global energy consumption and carbon emissions in the construction industry.With the upgrading of infrastructure and the improvement of building standards,traditional cement ... Cement stands as a dominant contributor to global energy consumption and carbon emissions in the construction industry.With the upgrading of infrastructure and the improvement of building standards,traditional cement fails to reconcile ecological responsibility with advanced functional performance.By incorporating tailored fillers into cement matrices,the resulting composites achieve enhanced thermoelectric(TE)conversion capabilities.These materials can harness solar radiation from building envelopes and recover waste heat from indoor thermal gradients,facilitating bidirectional energy conversion.This review offers a comprehensive and timely overview of cementbased thermoelectric materials(CTEMs),integrating material design,device fabrication,and diverse applications into a holistic perspective.It summarizes recent advancements in TE performance enhancement,encompassing fillers optimization and matrices innovation.Additionally,the review consolidates fabrication strategies and performance evaluations of cement-based thermoelectric devices(CTEDs),providing detailed discussions on their roles in monitoring and protection,energy harvesting,and smart building.We also address sustainability,durability,and lifecycle considerations of CTEMs,which are essential for real-world deployment.Finally,we outline future research directions in materials design,device engineering,and scalable manufacturing to foster the practical application of CTEMs in sustainable and intelligent infrastructure. 展开更多
关键词 Functional cement Thermoelectric materials Device structure Smart building
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Superelastic and Washable Micro/Nanofibrous Sponges Based on Biomimetic Helical Fibers for Efficient Thermal Insulation
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作者 Fengjin Yang Zhifei Wang +7 位作者 Wei Zhang Sai Wang Yi‑Tao Liu Fei Wang Roman ASurmenev Jianyong Yu Shichao Zhang Bin Ding 《Nano-Micro Letters》 2026年第2期170-182,共13页
Extreme cold weather seriously harms human thermoregulatory system,necessitating high-performance insulating garments to maintain body temperature.However,as the core insulating layer,advanced fibrous materials always... Extreme cold weather seriously harms human thermoregulatory system,necessitating high-performance insulating garments to maintain body temperature.However,as the core insulating layer,advanced fibrous materials always struggle to balance mechanical properties and thermal insulation,resulting in their inability to meet the demands for both washing resistance and personal protection.Herein,inspired by the natural spring-like structures of cucumber tendrils,a superelastic and washable micro/nanofibrous sponge(MNFS)based on biomimetic helical fibers is directly prepared utilizing multiple-jet electrospinning technology for high-performance thermal insulation.By regulating the conductivity of polyvinylidene fluoride solution,multiple-jet ejection and multiple-stage whipping of jets are achieved,and further control of phase separation rates enables the rapid solidification of jets to form spring-like helical fibers,which are directly entangled to assemble MNFS.The resulting MNFS exhibits superelasticity that can withstand large tensile strain(200%),1000 cyclic tensile or compression deformations,and retain good resilience even in liquid nitrogen(-196℃).Furthermore,the MNFS shows efficient thermal insulation with low thermal conductivity(24.85 mW m^(-1)K^(-1)),close to the value of dry air,and remains structural stability even after cyclic washing.This work offers new possibilities for advanced fibrous sponges in transportation,environmental,and energy applications. 展开更多
关键词 ELECTROSPINNING Micro/nanofibrous sponge Hierarchical structure SUPERELASTICITY Thermal insulation
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Te-Modulated Fe Single Atom with Synergistic Bidirectional Catalysis for High-Rate and Long-Cycling Lithium-Sulfur Battery
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作者 Jian Guo Lu Chen +4 位作者 Lijun Wang Kangfei Liu Ting He Jia Yu Hongbin Zhao 《Nano-Micro Letters》 2026年第1期827-842,共16页
Single-atom catalysts(SACs)have garnered significant attention in lithium-sulfur(Li-S)batteries for their potential to mitigate the severe polysulfide shuttle effect and sluggish redox kinetics.However,the development... Single-atom catalysts(SACs)have garnered significant attention in lithium-sulfur(Li-S)batteries for their potential to mitigate the severe polysulfide shuttle effect and sluggish redox kinetics.However,the development of highly efficient SACs and a comprehensive understanding of their structure-activity relationships remain enormously challenging.Herein,a novel kind of Fe-based SAC featuring an asymmetric FeN_(5)-TeN_(4) coordination structure was precisely designed by introducing Te atom adjacent to the Fe active center to enhance the catalytic activity.Theoretical calculations reveal that the neighboring Te atom modulates the local coordination environment of the central Fe site,elevating the d-band center closer to the Fermi level and strengthening the d-p orbital hybridization between the catalyst and sulfur species,thereby immobilizing polysulfides and improving the bidirectional catalysis of Li-S redox.Consequently,the Fe-Te atom pair catalyst endows Li-S batteries with exceptional rate performance,achieving a high specific capacity of 735 mAh g^(−1) at 5 C,and remarkable cycling stability with a low decay rate of 0.038%per cycle over 1000 cycles at 1 C.This work provides fundamental insights into the electronic structure modulation of SACs and establishes a clear correlation between precisely engineered atomic configurations and their enhanced catalytic performance in Li-S electrochemistry. 展开更多
关键词 Single-atom catalyst Coordination environment Electronic structure Bidirectional catalysis Li-S batteries
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Ponzi Scheme Detection for Smart Contracts Based on Oversampling
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作者 Yafei Liu Yuling Chen +2 位作者 Xuewei Wang Yuxiang Yang Chaoyue Tan 《Computers, Materials & Continua》 2026年第1期1065-1085,共21页
As blockchain technology rapidly evolves,smart contracts have seen widespread adoption in financial transactions and beyond.However,the growing prevalence of malicious Ponzi scheme contracts presents serious security ... As blockchain technology rapidly evolves,smart contracts have seen widespread adoption in financial transactions and beyond.However,the growing prevalence of malicious Ponzi scheme contracts presents serious security threats to blockchain ecosystems.Although numerous detection techniques have been proposed,existing methods suffer from significant limitations,such as class imbalance and insufficient modeling of transaction-related semantic features.To address these challenges,this paper proposes an oversampling-based detection framework for Ponzi smart contracts.We enhance the Adaptive Synthetic Sampling(ADASYN)algorithm by incorporating sample proximity to decision boundaries and ensuring realistic sample distributions.This enhancement facilitates the generation of high-quality minority class samples and effectively mitigates class imbalance.In addition,we design a Contract Transaction Graph(CTG)construction algorithm to preserve key transactional semantics through feature extraction from contract code.A graph neural network(GNN)is then applied for classification.This study employs a publicly available dataset from the XBlock platform,consisting of 318 verified Ponzi contracts and 6498 benign contracts.Sourced from real Ethereum deployments,the dataset reflects diverse application scenarios and captures the varied characteristics of Ponzi schemes.Experimental results demonstrate that our approach achieves an accuracy of 96%,a recall of 92%,and an F1-score of 94%in detecting Ponzi contracts,outperforming state-of-the-art methods. 展开更多
关键词 Blockchain smart contracts Ponzi schemes class imbalance graph structure construction
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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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GEMIN5 and neurodevelopmental diseases: From functional insights to disease perception
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作者 Encarnacion Martinez-Salas Rosario Francisco-Velilla 《Neural Regeneration Research》 2026年第1期187-194,共8页
GEMIN5 is a predominantly cytoplasmic multifunctional protein, known to be involved in recognizing snRNAs through its WD40 repeats domain placed at the N-terminus. A dimerization domain in the middle region acts as a ... GEMIN5 is a predominantly cytoplasmic multifunctional protein, known to be involved in recognizing snRNAs through its WD40 repeats domain placed at the N-terminus. A dimerization domain in the middle region acts as a hub for protein–protein interaction, while a non-canonical RNA-binding site is placed towards the C-terminus. The singular organization of structural domains present in GEMIN5 enables this protein to perform multiple functions through its ability to interact with distinct partners, both RNAs and proteins. This protein exerts a different role in translation regulation depending on its physiological state, such that while GEMIN5 down-regulates global RNA translation, the C-terminal half of the protein promotes translation of its mRNA. Additionally, GEMIN5 is responsible for the preferential partitioning of mRNAs into polysomes. Besides selective translation, GEMIN5 forms part of distinct ribonucleoprotein complexes, reflecting the dynamic organization of macromolecular complexes in response to internal and external signals. In accordance with its contribution to fundamental cellular processes, recent reports described clinical loss of function mutants suggesting that GEMIN5 deficiency is detrimental to cell growth and survival. Remarkably, patients carrying GEMIN5 biallelic variants suffer from neurodevelopmental delay, hypotonia, and cerebellar ataxia. Molecular analyses of individual variants, which are defective in protein dimerization, display decreased levels of ribosome association, reinforcing the involvement of the protein in translation regulation. Importantly, the number of clinical variants and the phenotypic spectrum associated with GEMIN5 disorders is increasing as the knowledge of the protein functions and the pathways linked to its activity augments. Here we discuss relevant advances concerning the functional and structural features of GEMIN5 and its separate domains in RNA-binding, protein interactome, and translation regulation, and how these data can help to understand the involvement of protein malfunction in clinical variants found in patients developing neurodevelopmental disorders. 展开更多
关键词 Gemin5 variants modular organization neurodevelopmental diseases RNA-binding proteins selective translation structural domains
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Cobalt‑Based Electrocatalysts for Sustainable Nitrate Conversion:Structural Design and Mechanistic Advancements
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作者 GuoLiang Chang Xueqiu Chen +2 位作者 Jing‑Jing Lv Zhijie Kong Zheng‑Jun Wang 《Nano-Micro Letters》 2026年第3期37-84,共48页
Electrocatalytic nitrate-to-ammonia conversion offers dual environmental and sustainable synthesis benefits,but achieving high efficiency with low-cost catalysts remains a major challenge.This review focuses on cobalt... Electrocatalytic nitrate-to-ammonia conversion offers dual environmental and sustainable synthesis benefits,but achieving high efficiency with low-cost catalysts remains a major challenge.This review focuses on cobalt-based electrocatalysts,emphasizing their structural engineering for enhanced the performance of electrocatalytic nitrate reduction reaction(NO3RR)through dimensional control,compositional tuning,and coordination microenvironment modulation.Notably,by critically analyzing metallic cobalt,cobalt alloys,cobalt compounds,cobalt single atom and molecular catalyst configurations,we firstly establish correlations between atomic-scale structural features and catalytic performance in a coordination environment perspective for NO3RR,including the dynamic reconstruction during operation and its impact on active site.Synergizing experimental breakthroughs with computational modeling,we decode mechanisms underlying competitive hydrogen evolution suppression,intermediate adsorption-energy optimization,and durability enhancement in complex aqueous environments.The development of cobalt-based catalysts was summarized and prospected,and the emerging opportunities of machine learning in accelerating the research and development of high-performance catalysts and the configuration of series reactors for scalable nitrate-to-ammonia systems were also introduced.Bridging surface science and applications,it outlines a framework for designing multifunctional electrocatalysts to restore nitrogen cycle balance sustainably. 展开更多
关键词 Electrocatalytic nitrate reduction reaction Cobalt-based Electrocatalysts Electronic structure Coordination environment
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