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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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Solidification modes and delta-ferrite of two types of 316L stainless steels:a combination of as-cast microstructure and HT-CLSM research 被引量:2
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作者 Yang Wang Chao Chen +5 位作者 Xiao-yu Yang Zheng-rui Zhang Jian Wang Zhou Li Lei Chen Wang-zhong Mu 《Journal of Iron and Steel Research International》 2025年第2期426-436,共11页
In 316L austenitic stainless steel,the presence of ferrite phase severely affects the non-magnetic properties.316L austenitic stainless steel with low-alloy type(L-316L)and high-alloy type(H-316L)has been studied.The ... In 316L austenitic stainless steel,the presence of ferrite phase severely affects the non-magnetic properties.316L austenitic stainless steel with low-alloy type(L-316L)and high-alloy type(H-316L)has been studied.The microstructure and solidification kinetics of the two as-cast grades were in situ observed by high temperature confocal laser scanning microscopy(HT-CLSM).There are significant differences in the as-cast microstructures of the two 316L stainless steel compositions.In L-316L steel,ferrite morphology appears as the short rods with a ferrite content of 6.98%,forming a dual-phase microstructure consisting of austenite and ferrite.Conversely,in H-316L steel,the ferrite appears as discontinuous network structures with a content of 4.41%,forming a microstructure composed of austenite and sigma(σ)phase.The alloying elements in H-316L steel exhibit a complex distribution,with Ni and Mo enriching at the austenite grain boundaries.HT-CLSM experiments provide the real-time observation of the solidification processes of both 316L specimens and reveal distinct solidification modes:L-316L steel solidifies in an FA mode,whereas H-316L steel solidifies in an AF mode.These differences result in ferrite and austenite predominantly serving as the nucleation and growth phases,respectively.The solidification mode observed by experiments is similar to the thermodynamic calculation results.The L-316L steel solidified in the FA mode and showed minimal element segregation,which lead to a direct transformation of ferrite to austenite phase(δ→γ)during phase transformation after solidification.Besides,the H-316L steel solidified in the AF mode and showed severe element segregation,which lead to Mo enrichment at grain boundaries and transformation of ferrite into sigma and austenite phases through the eutectoid reaction(δ→σ+γ). 展开更多
关键词 316L austenitic stainless steel As-cast microstructure High-temperature confocal laser scanning microscopy Solidification mode FERRITE Characterization
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Recent advances on the oxide film of ignition-proof magnesium alloys:A review 被引量:1
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作者 Jiaxuan Han Bo Hu +5 位作者 Zhenfei Jiang Fanjin Yao Zixin Li Dejiang Li Xiaoqin Zeng Wenjiang Ding 《Journal of Magnesium and Alloys》 2025年第1期4-29,共26页
Magnesium and its alloys offer lightweight advantage and have extensive development prospects,particularly in aerospace.However,their flammability poses a significant barrier on the development of Mg alloys.The igniti... Magnesium and its alloys offer lightweight advantage and have extensive development prospects,particularly in aerospace.However,their flammability poses a significant barrier on the development of Mg alloys.The ignition resistance of these alloys often depends on the protectiveness of the oxide film formed on the surface.This paper elucidates the formation mechanism of oxide film from thermodynamics and kinetics,classifying oxide films based on their layered structure to assess their protective properties.Furthermore,it comprehensively reviews the impact of characteristics on the protective effectiveness such as compactness,continuity,thickness,and mechanical properties.The paper also introduces various characterization methods for the microstructure and properties of oxide film.The primary objective of this paper is to enhance the comprehension of oxide film concerning the ignition resistance of Mg alloys and to furnish references for future advancements and research in Mg alloys with heightened ignition resistance. 展开更多
关键词 Magnesium alloys Ignition resistance Oxide film Layered structure Characterization methods
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Research on the application of defect engineering in the field of environmental catalysis 被引量:1
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作者 Sirui Gao Shunzheng Zhao +3 位作者 Xiaolong Tang Long Sun Qiyu Li Honghong Yi 《Green Energy & Environment》 2025年第6期1187-1209,共23页
Researchers have recently developed various surface engineering approaches to modify environmental catalysts and improve their catalytic activity.Defect engineering has proved to be one of the most promising modificat... Researchers have recently developed various surface engineering approaches to modify environmental catalysts and improve their catalytic activity.Defect engineering has proved to be one of the most promising modification methods.Constructing defects on the surface of catalytic materials can effectively modulate the coordination environment of the active sites,affecting and changing the electrons,geometry,and other important properties at the catalytic active sites,thus altering the catalytic activity of the catalysts.However,the conformational relationship between defects and catalytic activity remains to be clarified.This dissertation focuses on an overview of recent advances in defect engineering in environmental catalysis.Based on defining the classification of defects in catalytic materials,defect construction methods,and characterization techniques are summarized and discussed.Focusing on an overview of the characteristics of the role of defects in electrocatalytic,photocatalytic,and thermal catalytic reactions and the mechanism of catalytic reactions.An elaborate link is given between the reaction activity and the structure of catalyst defects.Finally,the existing challenges and possible future directions for the application of defect engineering in environmental catalysis are discussed,which are expected to guide the design and development of efficient environmental catalysts and mechanism studies. 展开更多
关键词 Defect engineering Environmental catalysis Characterization techniques Active sites
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Laboratory Diagnosis and Molecular Epidemiological Characterization of the First Imported Case of Lassa Fever in China 被引量:1
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作者 Yuliang Feng Wei Li +11 位作者 Mingfeng Jiang Hongrong Zhong Wei Wu Lyubo Tian Guo Chen Zhenhua Chen Can Luo Rongmei Yuan Xingyu Zhou Jiandong Li Xiaorong Yang Ming Pan 《Biomedical and Environmental Sciences》 2025年第3期279-289,共11页
Objective This study reports the first imported case of Lassa fever(LF)in China.Laboratory detection and molecular epidemiological analysis of the Lassa virus(LASV)from this case offer valuable insights for the preven... Objective This study reports the first imported case of Lassa fever(LF)in China.Laboratory detection and molecular epidemiological analysis of the Lassa virus(LASV)from this case offer valuable insights for the prevention and control of LF.Methods Samples of cerebrospinal fluid(CSF),blood,urine,saliva,and environmental materials were collected from the patient and their close contacts for LASV nucleotide detection.Whole-genome sequencing was performed on positive samples to analyze the genetic characteristics of the virus.Results LASV was detected in the patient’s CSF,blood,and urine,while all samples from close contacts and the environment tested negative.The virus belongs to the lineage IV strain and shares the highest homology with strains from Sierra Leone.The variability in the glycoprotein complex(GPC)among different strains ranged from 3.9%to 15.1%,higher than previously reported for the seven known lineages.Amino acid mutation analysis revealed multiple mutations within the GPC immunogenic epitopes,increasing strain diversity and potentially impacting immune response.Conclusion The case was confirmed through nucleotide detection,with no evidence of secondary transmission or viral spread.The LASV strain identified belongs to lineage IV,with broader GPC variability than previously reported.Mutations in the immune-related sites of GPC may affect immune responses,necessitating heightened vigilance regarding the virus. 展开更多
关键词 Lassa fever The first imported case Laboratory diagnosis Epidemiological characterization
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Physics-integrated neural networks for improved mineral volumes and porosity estimation from geophysical well logs 被引量:1
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作者 Prasad Pothana Kegang Ling 《Energy Geoscience》 2025年第2期394-410,共17页
Accurate estimation of mineralogy from geophysical well logs is crucial for characterizing geological formations,particularly in hydrocarbon exploration,CO_(2) sequestration,and geothermal energy development.Current t... Accurate estimation of mineralogy from geophysical well logs is crucial for characterizing geological formations,particularly in hydrocarbon exploration,CO_(2) sequestration,and geothermal energy development.Current techniques,such as multimineral petrophysical analysis,offer details into mineralogical distribution.However,it is inherently time-intensive and demands substantial geological expertise for accurate model evaluation.Furthermore,traditional machine learning techniques often struggle to predict mineralogy accurately and sometimes produce estimations that violate fundamental physical principles.To address this,we present a new approach using Physics-Integrated Neural Networks(PINNs),that combines data-driven learning with domain-specific physical constraints,embedding petrophysical relationships directly into the neural network architecture.This approach enforces that predictions adhere to physical laws.The methodology is applied to the Broom Creek Deep Saline aquifer,a CO_(2) sequestration site in the Williston Basin,to predict the volumes of key mineral constituents—quartz,dolomite,feldspar,anhydrite,illite—along with porosity.Compared to traditional artificial neural networks (ANN),the PINN approach demonstrates higher accuracy and better generalizability,significantly enhancing predictive performance on unseen well datasets.The average mean error across the three blind wells is 0.123 for ANN and 0.042 for PINN,highlighting the superior accuracy of the PINN approach.This method reduces uncertainties in reservoir characterization by improving the reliability of mineralogy and porosity predictions,providing a more robust tool for decision-making in various subsurface geoscience applications. 展开更多
关键词 Physics integrated neural networks PETROPHYSICS Well logs Oil and gas Reservoir characterization MINERALOGY Machine learning
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Recent advances of metal vacancies in energy and environmental catalysis:Synthesis,characterization,and roles
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作者 Long Sun Shunzheng Zhao +4 位作者 Sirui Gao Ronghui Zhu Yiran Tan Xiaolong Tang Honghong Yi 《Green Energy & Environment》 SCIE EI CAS 2025年第1期84-108,共25页
With the ongoing depletion of fossil fuels,energy and environmental issues have become increasingly critical,necessitating the search for effective solutions.Catalysis,being one of the hallmarks of modern industry,off... With the ongoing depletion of fossil fuels,energy and environmental issues have become increasingly critical,necessitating the search for effective solutions.Catalysis,being one of the hallmarks of modern industry,offers a promising avenue for researchers.However,the question of how to significantly enhance the performance of catalysts has gradually drawn the attention of scholars.Defect engineering,a commonly employed and effective approach to improve catalyst activity,has become a significant research focus in the catalysis field in recent years.Nonmetal vacancies have received extensive attention due to their simple form.Consequently,exploration of metal vacancies has remained stagnant for a considerable period,resulting in a scarcity of comprehensive reviews on this topic.Therefore,based on the latest research findings,this paper summarizes and consolidates the construction strategies for metal vacancies,characterization techniques,and their roles in typical energy and environmental catalytic reactions.Additionally,it outlines potential challenges in the future,aiming to provide valuable references for researchers interested in investigating metal vacancies. 展开更多
关键词 Metal vacancies CATALYSIS Construction strategies Characterization techniques ROLES
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Hydrothermal temperature-dependent compositions and copper complexing behaviors of hydrochar-derived dissolved organic matter: Insights from FT-ICR MS and multi-spectroscopic analysis 被引量:1
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作者 Bingfa Chen Xincai Gu +6 位作者 Muhua Feng Yanfang Feng Bingyu Wang Bensheng You Jingcheng Zheng Hong Liu Shiqun Han 《Journal of Environmental Sciences》 2025年第6期685-700,共16页
The copper complexing of dissolved organic matter released from hydrochar(HDOM)affects the former’s environmental behavior.In this study,how hydrothermal temperatures(180,220 and 260℃)influence the molecular-level c... The copper complexing of dissolved organic matter released from hydrochar(HDOM)affects the former’s environmental behavior.In this study,how hydrothermal temperatures(180,220 and 260℃)influence the molecular-level constitutions and Cu(II)binding features of HDOM were elucidated via fourier transform ion cyclotron resonance mass spectrometry and multi-spectroscopic analysis.The findings demonstrated that the almost HDOM molecules had the traits of lower polarity and higher hydrophobicity.As the hydrothermal temperature increased,the molecules with particularly high relative strength gradually disappeared,average molecular weight,percentages of CHON and aliphatic compounds of HDOM reduced while the percentages of CHO and aromatic compounds increased.In general,the fluorescence quenching of Cu(II)weakened as hydrothermal temperature rose and the Cu(II)binding stability constants of fluorophores in HDOM were 4.50–5.31.In addition,the Cu(II) binding order of fluorophores in HDOM showed temperature heterogeneities, andpolysaccharides or aromatic rings of non-fluorescent substances had the fastest responsesto Cu(II) binding. Generally, fluorescent components tend to bind Cu(II) at relatively traceconcentrations (0–40 μmol/L), whereas non-fluorescent substances tend to the bind Cu(II)at relatively higher concentrations (50–100 μmol/L). This study contributed to the predictionof the potential environmental behaviors and risks of Cu(II) at the molecular level afterhydrochar application. 展开更多
关键词 Hydrochar Dissolved organic matter Molecular characterizations Cu(II)binding Two-dimensional correlation analysis(2D-COS)
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Morphological Mechanism and Experimental Verification of Self-healing of Basalt-fiber Modified Water-soaked Asphalt
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作者 XIAO Minmin DONG Jinyong +2 位作者 LI Chunyan GUO Xu REN Jianguo 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2025年第1期171-186,共16页
This study investigates the mechanism of action of representative molecules of basalt fibers on the healing of water-soaked asphalt.Thermodynamic parameters,morphological characteristics,interfacial healing energy,and... This study investigates the mechanism of action of representative molecules of basalt fibers on the healing of water-soaked asphalt.Thermodynamic parameters,morphological characteristics,interfacial healing energy,and interfacial healing strength were analyzed using molecular dynamics and macroscopic tests under different time,temperature,and water conditions to evaluate the specific states and critical conditions involved in self-healing.The results indicate that basalt-fiber molecules can induce rearrangement and a combination of water-soaked asphalt at the healing interface.Hydroxyl groups with different bonding states increase the interfacial adsorption capacity of water-soaked asphalt.The interaction between basalt fiber molecules and water molecules leads to a"hoop"phenomenon,while aromatics-2 molecules exhibit a"ring band aggregation"phenomenon.The former reduces the miscibility of water and asphalt molecules,while the latter causes slow diffusion of the components.Furthermore,a micro-macro dual-scale comparison of interfacial healing strength was conducted at temperatures of 297.15 and 312.15 K to identify the strength transition point and critical temperature of 299.4 K during the self-healing process of basalt-fiber modified water-soaked asphalt. 展开更多
关键词 water-soaked asphalt basalt-fibers self-healing properties moisture status molecular characterization
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Prediction of joint roughness coefficient via hybrid machine learning model combined with principal components analysis 被引量:1
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作者 Shijie Xie Hang Lin +2 位作者 Tianxing Ma Kang Peng Zhen Sun 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第4期2291-2306,共16页
Joint roughness coefficient(JRC)is the most commonly used parameter for quantifying surface roughness of rock discontinuities in practice.The system composed of multiple roughness statistical parameters to measure JRC... Joint roughness coefficient(JRC)is the most commonly used parameter for quantifying surface roughness of rock discontinuities in practice.The system composed of multiple roughness statistical parameters to measure JRC is a nonlinear system with a lot of overlapping information.In this paper,a dataset of eight roughness statistical parameters covering 112 digital joints is established.Then,the principal component analysis method is introduced to extract the significant information,which solves the information overlap problem of roughness characterization.Based on the two principal components of extracted features,the white shark optimizer algorithm was introduced to optimize the extreme gradient boosting model,and a new machine learning(ML)prediction model was established.The prediction accuracy of the new model and the other 17 models was measured using statistical metrics.The results show that the prediction result of the new model is more consistent with the real JRC value,with higher recognition accuracy and generalization ability. 展开更多
关键词 Rock discontinuities Joint roughness coefficient(JRC) Roughness characterization Principal components analysis(PCA) Machine learning
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Advancements and Challenges in Organic–Inorganic Composite Solid Electrolytes for All‑Solid‑State Lithium Batteries
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作者 Xueyan Zhang Shichao Cheng +4 位作者 Chuankai Fu Geping Yin Liguang Wang Yongmin Wu Hua Huo 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期46-97,共52页
To address the limitations of contemporary lithium-ion batteries,particularly their low energy density and safety concerns,all-solid-state lithium batteries equipped with solid-state electrolytes have been identified ... To address the limitations of contemporary lithium-ion batteries,particularly their low energy density and safety concerns,all-solid-state lithium batteries equipped with solid-state electrolytes have been identified as an up-and-coming alternative.Among the various SEs,organic–inorganic composite solid electrolytes(OICSEs)that combine the advantages of both polymer and inorganic materials demonstrate promising potential for large-scale applications.However,OICSEs still face many challenges in practical applications,such as low ionic conductivity and poor interfacial stability,which severely limit their applications.This review provides a comprehensive overview of recent research advancements in OICSEs.Specifically,the influence of inorganic fillers on the main functional parameters of OICSEs,including ionic conductivity,Li+transfer number,mechanical strength,electrochemical stability,electronic conductivity,and thermal stability are systematically discussed.The lithium-ion conduction mechanism of OICSE is thoroughly analyzed and concluded from the microscopic perspective.Besides,the classic inorganic filler types,including both inert and active fillers,are categorized with special emphasis on the relationship between inorganic filler structure design and the electrochemical performance of OICSEs.Finally,the advanced characterization techniques relevant to OICSEs are summarized,and the challenges and perspectives on the future development of OICSEs are also highlighted for constructing superior ASSLBs. 展开更多
关键词 Composite solid electrolytes Inorganic filler Interfacial stability Li-ion conduction mechanism Characterization techniques
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SiO_(2)'-CaO/(CaO+K_(2)O)(S'CK)Diagram as a Petrochemical Tool for Deciphering the Tectono-Magmatic Characterization of Granitoid Suites 被引量:1
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作者 SUN Mingming WANG Yang 《Acta Geologica Sinica(English Edition)》 2025年第2期598-610,共13页
The SiO_(2)'-CaO/(CaO+K_(2)O)(S'CK)diagram is an empirically derived major element-based equivalent to the modal IUGS alkali feldspar-quartz-plagioclase classification scheme for granitoids.It employs the cont... The SiO_(2)'-CaO/(CaO+K_(2)O)(S'CK)diagram is an empirically derived major element-based equivalent to the modal IUGS alkali feldspar-quartz-plagioclase classification scheme for granitoids.It employs the content of SiO_(2)and CaO/(CaO+K_(2)O)ratio to approximate the IUGS classification diagram and a normative-based Q'-ANOR plot.Four trends have been superimposed onto the SiO_(2)'-CaO/(CaO+K_(2)O)diagram based on published datasets from the Peninsular Ranges(calcic:C),Tuolumne(calc-alkalic:CA),Sherman(alkali-calcic:AC),and Bjerkreim-Sokndal(alkalic:A)batholiths,which were employed to constrain the positions of the C-CA,CA-AC and AC-A suite boundaries on the SiO_(2)versus(Na_(2)O+K_(2)O-CaO)(or modified alkali-lime index,MALI)granitic classification diagram.A merit of the SiO_(2)'-CaO/(CaO+K_(2)O)plot is identifying rock types comprising a suite and their relative abundances.The distinguished projections of five typical granitoid assemblages,which are summarized by Bonin et al.(2020),demonstrate the ability of SiO_(2)'-CaO/(CaO+K_(2)O)diagram to decipher their petrogenesis.The SiO_(2)'-CaO/(CaO+K_(2)O)plots for the plutonic suites of'known'tectonic settings can reveal their evolution paths and the lithological statistics.Accordingly,it is suggested that the SiO_(2)'-CaO/(CaO+K_(2)O)plot can distinguish the tectonic environments of plutonic suits by comparing the plutonic suites or batholiths of'unknown'tectonic context to the published datasets from granitoid suites formed within'known'tectonic settings.The modified SiO_(2)'-CaO/(CaO+K_(2)O)diagram links the bulk chemical composition of granitoid suites to the likely source,magmatic evolution,and tectonic setting;thus,it may be a useful tectono-magmatic classification scheme for granitoid suites. 展开更多
关键词 classification of granitoid major-element chemistry SiO_(2)'–CaO/(CaO+K_(2)O)diagram tectono-magmatic character
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“Zero‑Strain” NiNb_(2)O_(6) Fibers for All‑Climate Lithium Storage
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作者 Yan Zhao Qiang Yuan +5 位作者 Liting Yang Guisheng Liang Yifeng Cheng Limin Wu Chunfu Lin Renchao Che 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期348-360,共13页
Niobates are promising all-climate Li^(+)-storage anode material due to their fast charge transport,large specific capacities,and resistance to electrolyte reaction.However,their moderate unit-cellvolume expansion(gen... Niobates are promising all-climate Li^(+)-storage anode material due to their fast charge transport,large specific capacities,and resistance to electrolyte reaction.However,their moderate unit-cellvolume expansion(generally 5%–10%)during Li^(+)storage causes unsatisfactory long-term cyclability.Here,“zero-strain”NiNb_(2)O_(6) fibers are explored as a new anode material with comprehensively good electrochemical properties.During Li^(+)storage,the expansion of electrochemical inactive NiO_(6) octahedra almost fully offsets the shrinkage of active NbO_(6) octahedra through reversible O movement.Such superior volume-accommodation capability of the NiO_(6) layers guarantees the“zero-strain”behavior of NiNb_(2)O_(6) in a broad temperature range(0.53%//0.51%//0.74%at 25//−10//60℃),leading to the excellent cyclability of the NiNb_(2)O_(6) fibers(92.8%//99.2%//91.1%capacity retention after 1000//2000//1000 cycles at 10C and 25//−10//60℃).This NiNb_(2)O_(6) material further exhibits a large reversible capacity(300//184//318 mAh g−1 at 0.1C and 25//−10//60℃)and outstanding rate performance(10 to 0.5C capacity percentage of 64.3%//50.0%//65.4%at 25//−10//60℃).Therefore,the NiNb_(2)O_(6) fibers are especially suitable for large-capacity,fast-charging,long-life,and all-climate lithium-ion batteries. 展开更多
关键词 NiNb_(2)O_(6)porous fiber “Zero-strain”mechanism Electrochemical property Harsh-temperature operation Operando characterization
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A dataset for the structure and electrochemical performance of hard carbon as anodes for sodium-ion batteries
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作者 HOU Wei-yan YI Zong-lin +7 位作者 JIA Wan-ru YU Hong-tao DAI Li-qin YANG Jun-jie CHEN Jing-peng XIE Li-jing SU Fang-yuan CHEN Cheng-meng 《新型炭材料(中英文)》 北大核心 2025年第5期1193-1200,共8页
This data set collects,compares and contrasts the capacities and structures of a series of hard carbon materials,and then searches for correlations between structure and electrochemical performance.The capacity data o... This data set collects,compares and contrasts the capacities and structures of a series of hard carbon materials,and then searches for correlations between structure and electrochemical performance.The capacity data of the hard carbons were obtained by charge/discharge tests and the materials were characterized by XRD,gas adsorption,true density tests and SAXS.In particular,the fitting of SAXS gave a series of structural parameters which showed good characterization.The related test details are given with the structural data of the hard carbons and the electrochemical performance of the sodium-ion batteries. 展开更多
关键词 Hard carbon Sodium-ion battery SAXS Structural characterization DATASET
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Synthesis and crystal structure characterization of yttrium imido complex:The reactivity of 2-substituted-1-amino-o-carborane with yttrium dialkyl complex
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作者 GUO Liping 《无机化学学报》 北大核心 2025年第7期1409-1415,共7页
2-substituted-1-amino-o-carboranes 2-R-1-NH_(2)-o-C_(2)B_(10)H_(10)(R=CH_(3),1a;R=Ph,1b)were synthesized and the reactions of these compounds with the yttrium dialkyl complex[Y(L)(CH_(2)SiMe3)_(2)](L=[2-(2,5-Me_(2)C_(... 2-substituted-1-amino-o-carboranes 2-R-1-NH_(2)-o-C_(2)B_(10)H_(10)(R=CH_(3),1a;R=Ph,1b)were synthesized and the reactions of these compounds with the yttrium dialkyl complex[Y(L)(CH_(2)SiMe3)_(2)](L=[2-(2,5-Me_(2)C_(4)H_(2)N)C_(6)H4NC(Ph)=NDipp]-,Dipp=2,6-iPr_(2)C_(6)H_(3))were investigated.The 1H NMR spectroscopy indicate that the reaction of ytrrium dialkyl complex with one equivalent of 2-R-1-NH_(2)-o-C_(2)B_(10)H_(10) produce the mixture of ytrrium alkyl-amido complex[Y(L)(2-R-1-NH-o-C_(2)B_(10)H_(10))(CH_(2)SiMe3)](R=CH_(3),2a;R=Ph,2b)and bis(amido)complex[Y(L)(2-R-1-NH-o-C_(2)B_(10)H_(10))_(2)](R=CH_(3),3a;R=Ph,3b).The yttrium bridging imido complex[Y(L)(2-CH_(3)-1-N-o-C_(2)B_(10)H_(10))]_(2)(4a)was obtained by heating the mixture at 55℃for 12 h.Complex 3a was isolated and characterized by treating the yttrium dialkyl complex with two equivalents of 1a.The structures of complexes 3a and 4a were verified by single-crystal Xray diffraction.CCDC:2424136,3a;2424137,4a. 展开更多
关键词 yttrium imide O-CARBORANE synthesis structure characterization
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In situ synthesis,crystal structure,and magnetic characterization of a trinuclear copper complex based on a multi-substituted imidazo[1,5-a]pyrazine scaffold
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作者 WANG Zhaodong 《无机化学学报》 北大核心 2025年第3期597-604,共8页
A trinuclear copper complex [Cu_(3)(L2)_(2)(SO_(4))_(2)(H_(2)O)_(7)]·8H_(2)O(1)(HL2=1-hydroxy-3-(pyrazin-2-yl)-N-(pyrazin-2-ylmethyl)imidazo[1,5-a]pyrazine-8-carboxamide) with a multi-substituted imidazo[1,5-a]py... A trinuclear copper complex [Cu_(3)(L2)_(2)(SO_(4))_(2)(H_(2)O)_(7)]·8H_(2)O(1)(HL2=1-hydroxy-3-(pyrazin-2-yl)-N-(pyrazin-2-ylmethyl)imidazo[1,5-a]pyrazine-8-carboxamide) with a multi-substituted imidazo[1,5-a]pyrazine scaffold was serendipitously prepared from the reaction of the pro-ligand of H_(2)L1(N,N'-bis(pyrazin-2-ylmethyl)pyrazine-2,3-dicarboxamide) with CuSO_(4)·5H_(2O) in aqueous solution at room temperature.Complex 1 was characterized by IR,single-crystal X-ray analysis,and magnetic susceptibility measurements.Single-crystal X-ray analysis reveals that the complex consists of three Cu(Ⅱ) ions,two in situ transformed L2~-ligands,two coordinated sulfates,seven coordinated water molecules,and eight uncoordinated water molecules.Magnetic susceptibility measurement indicates that there are obvious ferromagnetic coupling interactions between the adjacent Cu(Ⅱ) ions in 1.CCDC:1852713. 展开更多
关键词 amide ligand copper complex single crystal structure C-N coupling magnetic characterization
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Heterologous Expression,Purification and Enzymatic Characterization of Xylitol Dehydrogenase from the Thermophilic Fungus Talaromyces emersonii
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作者 MENG Er QU Cong +8 位作者 YI Ke LI Hui-Min DUAN Xin-Yi ZHANG Zhe-Yuan HE Shao-Long LUO Yu-Tao WU Lei ZHANG Dong-Yi LIU Chang-Jun 《中国生物化学与分子生物学报》 北大核心 2025年第7期1007-1018,共12页
The xylitol dehydrogenase(XDH)is a crucial enzyme involved in the xylose utilization in pentose⁃catabolizing yeasts and fungi.In addition to producing xylulose,XDH can also be employed to develop a biosensor for monit... The xylitol dehydrogenase(XDH)is a crucial enzyme involved in the xylose utilization in pentose⁃catabolizing yeasts and fungi.In addition to producing xylulose,XDH can also be employed to develop a biosensor for monitoring xylitol concentration.In this study,the gene encoding the thermophilic fungus Talaromyces emersonii XDH(TeXDH)was heterologously expressed in Escherichia coli BL21(DE3)at 16℃in the soluble form.Recombinant TeXDH with high purity was purified by using a Ni⁃NTA affinity column.Size⁃exclusion chromatography and SDS⁃PAGE analysis demonstrated that the puri⁃fied recombinant TeXDH exists as a native trimer with a molecular mass of approximately 116 kD,and is composed of three identical subunits,each with a molecular weight of around 39 kD.The TeXDH strictly preferred NAD^(+)as a coenzyme to NADP^(+).The optimal temperature and pH of the TeXDH were 40℃and 10.0,respectively.After EDTA treatment,the enzyme activity of TeXDH decreased to 43.26%of the initial enzyme activity,while the divalent metal ions Mg^(2+)or Ca^(2+)could recover the enzyme activity of TeXDH,reaching 103.32%and 110.69%of the initial enzyme activity,respectively,making them the optimal divalent metal ion cofactors for TeXDH enzyme.However,the divalent metal ions of Mn^(2+),Ni^(2+),Cu^(2+),Zn^(2+),Co^(2+),and Cd^(2+)significantly inhibited the activity of TeXDH.ICP⁃MS and molecular doc⁃king studies revealed that 1 mol/L of TeXDH bound 2 mol/L Zn^(2+)ions and 1 mol/L Mg^(2+)ion.Further⁃more,TeXDH exhibited a high specificity for xylitol,laying the foundation for the development of future xylitol biosensors. 展开更多
关键词 xylitol dehydrogenase(XDH) Talaromyces emersonii heterologous expression enzymatic characterization
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Solutions to SU(n+1)Toda systems with cone singularities via toric curves on compact Riemann surfaces
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作者 Jingyu Mu Yiqian Shi and Bin Xu 《中国科学技术大学学报》 北大核心 2025年第5期2-13,1,I0001,共14页
On a compact Riemann surface with finite punctures P_(1),…P_(k),we define toric curves as multivalued,totallyunramified holomorphic maps to P^(n)with monodromy in a maximal torus of PSU(n+1).Toric solutions to SU(n+1... On a compact Riemann surface with finite punctures P_(1),…P_(k),we define toric curves as multivalued,totallyunramified holomorphic maps to P^(n)with monodromy in a maximal torus of PSU(n+1).Toric solutions to SU(n+1)Todasystems on X\{P_(1);…;P_(k)}are recognized by the associated toric curves in.We introduce character n-ensembles as-tuples of meromorphic one-forms with simple poles and purely imaginary periods,generating toric curves on minus finitelymany points.On X,we establish a correspondence between character-ensembles and toric solutions to the SU(n+1)system with finitely many cone singularities.Our approach not only broadens seminal solutions with two conesingularities on the Riemann sphere,as classified by Jost-Wang(Int.Math.Res.Not.,2002,(6):277-290)andLin-Wei-Ye(Invent.Math.,2012,190(1):169-207),but also advances beyond the limits of Lin-Yang-Zhong’s existencetheorems(J.Differential Geom.,2020,114(2):337-391)by introducing a new solution class. 展开更多
关键词 SU(n+1)Toda system regular singularity unitary curve toric solution character ensemble
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High-pressure research on optoelectronic materials:Insights from in situ characterization methods
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作者 Songhao Guo Yiqiang Zhan Xujie Lü 《Matter and Radiation at Extremes》 2025年第3期10-23,共14页
High-pressure research has emerged as a pivotal approach for advancing our understanding and development of optoelectronic materials,which are vital for a wide range of applications,including photovoltaics,light-emitt... High-pressure research has emerged as a pivotal approach for advancing our understanding and development of optoelectronic materials,which are vital for a wide range of applications,including photovoltaics,light-emitting devices,and photodetectors.This review highlights various in situ characterization methods employed in high-pressure research to investigate the optical,electronic,and structural properties of optoelectronic materials.We explore the advances that have been made in techniques such as X-ray diffraction,absorption spectroscopy,nonlinear optics,photoluminescence spectroscopy,Raman spectroscopy,and photoresponse measurement,emphasizing how these methods have enhanced the elucidation of structural transitions,bandgap modulation,performance optimization,and carrier dynamics engineering.These insights underscore the pivotal role of high-pressure techniques in optimizing and tailoring optoelectronic materials for future applications. 展开更多
关键词 optoelectronic materialswe x ray diffraction nonlinear optics situ characterization methods situ characterization optoelectronic materialswhich absorption spectroscopy optoelectronic materials
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Erratum to:Hydrochemical characterization of surface waters in Northen Tehran:Integrating cluster-based techniques with Self-Organizing Maps
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作者 Maryam SALIMI Hamid Reza NASSERY +2 位作者 Meysam VADIATI Prosun BHATTACHARYA Akram RAHBAR 《Journal of Mountain Science》 2025年第9期3527-3527,共1页
The title of the online version of the original article was revised.The title of the original article has been revised to:Hydrochemical characterization of surface waters in Northern Tehran:Integrating cluster-based t... The title of the online version of the original article was revised.The title of the original article has been revised to:Hydrochemical characterization of surface waters in Northern Tehran:Integrating cluster-based techniques with Self-Organizing Maps. 展开更多
关键词 northern tehran cluster based techniques characterization surface waters hydrochemical characterization surface waters self organizing maps
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