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Do Planetary Transits Predict Synchronicity Experience?
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作者 Robert G. Sacco 《Journal of Behavioral and Brain Science》 CAS 2023年第3期33-44,共12页
Synchronicity involves the experience of personal meaning entangled with ambiguous coincidences in time. Ambiguity results from incomplete information about the chances of various events occurring. The problem that th... Synchronicity involves the experience of personal meaning entangled with ambiguous coincidences in time. Ambiguity results from incomplete information about the chances of various events occurring. The problem that this study addresses is the lack of empirical research on synchronicity. This study sought to address this problem by exploring the astrological hypothesis that planetary transits predict synchronicity events. Synchronicities were compared with the probability distributions of planetary transits. In comparison with the base rate prediction, planetary transits were not a significant predictor of synchronicity events. The findings of this study provide new insight into the complex, multifaceted, and ambiguous phenomenon of synchronicity. The concept of ambiguity tolerance plays a significant role in synchronicity research since ambiguity cannot be completely eliminated. 展开更多
关键词 ASTROLOGY Fibonacci Numbers Planetary transits SYNCHRONICITY
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Electrospun Nanofibrous Transition Metal-based Bifunctional Electrocatalysts Toward Overall Water Splitting
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作者 YIN Yongting LU Xiaofeng 《高等学校化学学报》 北大核心 2026年第1期87-107,共21页
Electrochemical water splitting represents a sustainable technology for hydrogen(H_(2))production.However,its large-scale implementation is hindered by the high overpotentials required for both the cathodic hydrogen e... Electrochemical water splitting represents a sustainable technology for hydrogen(H_(2))production.However,its large-scale implementation is hindered by the high overpotentials required for both the cathodic hydrogen evolution reaction(HER)and the anodic oxygen evolution reaction(OER).Transition metal-based catalysts have garnered significant research interest as promising alternatives to noble-metal catalysts,owing to their low cost,tunable composition,and noble-metal-like catalytic activity.Nevertheless,systematic reviews on their application as bifunctional catalysts for overall water splitting(OWS)are still limited.This review comprehensively outlines the principal categories of bifunctional transition metal electrocatalysts derived from electrospun nanofibers(NFs),including metals,oxides,phosphides,sulfides,and carbides.Key strategies for enhancing their catalytic performance are systematically summarized,such as heterointerface engineering,heteroatom doping,metal-nonmetal-metal bridging architectures,and single-atom site design.Finally,current challenges and future research directions are discussed,aiming to provide insightful perspectives for the rational design of high-performance electrocatalysts for OWS. 展开更多
关键词 Electrospinning Nanofibers Transition metal-based catalyst Overall water splitting Performance optimization
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Statistics and Development Analysis of Urban Rail Transit in China by the End of 2025
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作者 WANG Fuwen LIANG Shuaiwen FENG Aijun 《隧道建设(中英文)》 北大核心 2026年第2期437-444,I0005-I0012,共16页
First,statistics on the operational lines and mileage of urban rail transit in China are conducted.The results show that,as of Dec.31,2025,there were 60 cities with urban rail transit in operation nationwide,with a to... First,statistics on the operational lines and mileage of urban rail transit in China are conducted.The results show that,as of Dec.31,2025,there were 60 cities with urban rail transit in operation nationwide,with a total operational mileage of approximately 12837.8 km(excluding the electronic guideway rubber-tired system,there were 57 cities,with a total operational mileage of 12651.6 km).The metro system dominates,while low-capacity systems exhibit a multi-modal development pattern.Subsequently,the characteristics of China′s urban rail transit industry development are analyzed,indicating that:(1)It should closely align with the theme of urban intensive development,promote quality improvement and efficiency enhancement of existing lines,and focus on the supporting role of initial passenger flow for new line construction,multi-network integration,and economic and financial sustainability.(2)Significant innovative achievements have been made in safety resilience,green and low-carbon development,intelligent construction,and digital transformation.Finally,development recommendations for the"15th Five-Year Plan"period are proposed:promoting cost reduction and efficiency improvement in the rail transit industry,enhancing the operational efficiency of existing networks,continuously exploring railway services for urban commuting,strengthening external exchanges,and driving the"going global"strategy of the urban rail transit industry. 展开更多
关键词 rail transit operational lines data statistics development analysis
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Manganese‑doped poly(1,5‑diaminonaphthalene)based high‑performance supercapacitors
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作者 XU Mengying LI Wen +5 位作者 MEI Junzhong ZHANG Cheng Palanisamy Kannan LU Lei ZHANG Lianpeng WANG Peng 《无机化学学报》 北大核心 2026年第2期387-397,共11页
Herein,manganese(Mn)‑doped poly(1,5‑diaminonaphthalene)(PN)electrode material(Mn@PN)was synthesized via chemical oxidative polymerization.The material′s distinctive vesicular architecture enables rapid ion transport ... Herein,manganese(Mn)‑doped poly(1,5‑diaminonaphthalene)(PN)electrode material(Mn@PN)was synthesized via chemical oxidative polymerization.The material′s distinctive vesicular architecture enables rapid ion transport while maintaining the structural stability of the electrode under continuous charge‑discharge cycles.Electrochemical characterization under a three‑electrode system revealed exceptional rate capability:Mn@PN delivered an ultrahigh specific capacitance of 10318 F·g^(-1) at a low current density of 3 A·g^(-1) and retained 9415 F·g^(-1)(91.2%retention compared to the value at 3 A·g^(-1))even at an ultrahigh current density of 50 A·g^(-1).Moreover,the material exhibited 97.4%capacitance retention after 9000 cycles at 30 A·g^(-1),corresponding with a low capacitance decay rate of 0.003‰per cycle,significantly outperforming conventional conductive polymers like polyaniline(PANI).An asymmetric supercapacitor assembled with Mn@PN as the positive electrode(Mn@PN||AC)achieved an energy density of 328 Wh·kg^(-1) at 15 A·g^(-1) and retained 80.7%of its initial specific capacitance after 4000 cycles at 20 A·g^(-1). 展开更多
关键词 poly(1 5‑diaminonaphthalene) transition metal long‑cycle stability SUPERCAPACITOR
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Transition metal-catalyzed C-H activation/annulation for the construction of unnatural amino acids and peptides
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作者 Xiao Tang Erik V.Van der Eycken Liangliang Song 《Chinese Chemical Letters》 2026年第2期191-205,共15页
Peptides play important roles in chemistry,medicinal chemistry and life science,due to their high efficiency and specificity,unusual biological and therapeutic properties.As naturally occurring peptides often face wit... Peptides play important roles in chemistry,medicinal chemistry and life science,due to their high efficiency and specificity,unusual biological and therapeutic properties.As naturally occurring peptides often face with their intrinsic limitations including metabolic instability and low membrane permeability,the strategies for synthesizing unnatural amino acids and peptides are explored.Among the methods for modifying amino acids and peptides,chemo-and site-selective approaches are preferred because of the ability to fine-tuning structural features.Recently,transition metal-catalyzed Csingle bondH activation has been employed for the functionalization of amino acids and peptides.Through domino Csingle bondH activation/annulation,a series of structurally complex and diverse amino acids and peptides is constructed.This review highlights recent advances in the synthesis of unnatural amino acids and peptides via transition metal-catalyzed Csingle bondH activation/annulation. 展开更多
关键词 Amino acid PEPTIDE Transition metal C-H activation ANNULATION
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Rationally designed nickel-cobalt oxide/sulfide heterostructure for high-performance oxygen evolution reaction and anion exchange membrane water electrolysis
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作者 Hyeonji Kwon Hyeongseok Seo +3 位作者 Siyeon Kang Sang Eun Shim Kyeongseok Min Sung-Hyeon Baeck 《Journal of Energy Chemistry》 2026年第1期955-966,I0021,共13页
To realize the practical application of anion exchange membrane water electrolysis(AEMWE),it is essential to develop highly active,durable,and cost-effective electrocatalyst for oxygen evolution reaction(OER).Herein,w... To realize the practical application of anion exchange membrane water electrolysis(AEMWE),it is essential to develop highly active,durable,and cost-effective electrocatalyst for oxygen evolution reaction(OER).Herein,we report a hollow-structured Ni_(x)Co_(1−x)O/Ni_(3)S_(2)/Co_(9)S_(8)heterostructure synthesized via sequential template-assisted growth,thermal oxidation,and controlled sulfidation process.The abundant bimetallic heterointerfaces not only provide additional active sites but also promote electronic modulation via charge redistribution.Additionally,the porous and hollow architecture enhances active surface area and mass transfer ability,thereby increasing the number of accessible active sites for alkaline OER.As a result,the prepared electrocatalyst achieves low overpotential of 310 mV at 10 mA cm^(−2)and small Tafel slope of 55.94 mV dec^(−1),demonstrating the exceptional electrocatalytic performance for alkaline OER.When integrated as the anode in an AEMWE cell,it delivers outstanding performance with only 1.657 V at 1.0 A cm^(−2)and reaches high current density of 5.0 A cm^(−2)at 1.989 V,surpassing those of commercial RuO_(2).The cell also shows excellent long-term durability over 100 h with minimal degradation.This study highlights the strong potential of rationally engineered oxide/sulfide heterostructures for next-generation alkaline water electrolysis. 展开更多
关键词 AEMWE Oxygen evolution reaction Transition metal HETEROINTERFACE Hollow structure
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Advances in radical Smiles rearrangement
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作者 Nianhua Luo Jiayi Jiang +5 位作者 Muhammad Suleman Zhaowen Liu Shuping Huang Wei Xiao Jie Wu Jiapian Huang 《Chinese Chemical Letters》 2026年第2期159-176,共18页
The Smiles rearrangement is an exceptionally versatile method in organic synthesis,providing a broad canvas for designing cascade reactions that construct new Csp^(2)-Y(Y=C,O,N,S,CO,etc.)bonds.Among the various types ... The Smiles rearrangement is an exceptionally versatile method in organic synthesis,providing a broad canvas for designing cascade reactions that construct new Csp^(2)-Y(Y=C,O,N,S,CO,etc.)bonds.Among the various types of Smiles rearrangement,the radical-type variant has emerged as a more powerful,mild,efficient,and modern synthetic technique compared to its traditional ionic counterpart.This approach excels in generating new(hetero)aromatic migration products,enabling significant advancements in recent years.This tutorial review focuses on the recent progress,since 2016,in the development and application of radical Smiles rearrangement in organic chemistry.Special attention is paid to novel transformations achieved through photochemical,electrochemical,and transition metal catalysis methods. 展开更多
关键词 Radical Smiles rearrangement Radical chemistry PHOTOCATALYSIS ELECTROCATALYSIS Transition metal-catalyzed
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Synthesis of transition metal nitride nanomaterials for electrocatalytic applications
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作者 Shuai Zhang Yiming Wang +2 位作者 Jiezhou Wang Xixi Wang Yiyao Ge 《Science China Materials》 2026年第3期1291-1316,共26页
Transition metal nitrides(TMNs)have been considered as promising alternative catalysts to noble metals in various electrocatalytic applications due to their noble metal-like electronic structures,high conductivity,low... Transition metal nitrides(TMNs)have been considered as promising alternative catalysts to noble metals in various electrocatalytic applications due to their noble metal-like electronic structures,high conductivity,low cost,as well as strong chemical stability,which could resist corrosion and oxidation in harsh operation conditions.Therefore,the rational design and controlled synthesis of TMNs with distinct structures play a vital role in developing highly efficient electrocatalysts toward electrochemical applications.This review provides a comprehensive summary of representative synthetic strategies for TMNs,such as direct nitridation,solidstate reaction,sol-gel assisted reaction,and wet-chemical reaction,presents the distinct structural characterizations,and demonstrates their advances in the electrochemical applications.Finally,we propose the remaining challenges and the future research directions on the exploration of TMNs with well-defined structures for electrocatalytic applications,which could shed light on the future development of high-performance electrocatalysts. 展开更多
关键词 ELECTROCATALYSTS transition metal nitrides controlled synthesis NANOMATERIALS
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Effect of Nano-CaCO_(3)@SiO_(2)on Viscoelasticity of Asphalt
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作者 DAI Yu LIU Peng +1 位作者 HU Chuanlin ZHOU Qunce 《Journal of Wuhan University of Technology(Materials Science)》 2026年第1期116-120,共5页
Dynamic thermal mechanical analysis was used to evaluate the viscoelasticity of asphalt.The parameters included the energy storage modulus(E),the loss modulus(E'),and the loss tangent(tanδ).The impact of three ki... Dynamic thermal mechanical analysis was used to evaluate the viscoelasticity of asphalt.The parameters included the energy storage modulus(E),the loss modulus(E'),and the loss tangent(tanδ).The impact of three kinds of particles containing CaCO_(3)with different size and structure on the mechanical properties was also measured.The addition of limestone increases the glass transition temperature,while nanoCaCO_(3)@SiO_(2)decreases the glass transition temperature.Nano-CaCO_(3)has a negligible effect on the glass transition temperature.The particle size of the limestone is 0.075 mm,which is a material at the micrometer level.During the heating process,it hinders the molecular movement and makes the material harder.Thus the glass transition temperature is relatively high. 展开更多
关键词 ASPHALT low-temperature performance glass transition nano-CaCO_(3)
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Advances in organoelectrochemical copper-catalyzed reactions
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作者 Pan Zhou Ting Zou +2 位作者 Hong-Jian Song Yu-Xiu Liu Qing-Min Wang 《Chinese Chemical Letters》 2026年第1期25-38,共14页
The combination of electrochemistry and metal catalysts has been a popular research topic in the field of organic synthesis due to the abundance and controllable valence states of transition metals,where electron tran... The combination of electrochemistry and metal catalysts has been a popular research topic in the field of organic synthesis due to the abundance and controllable valence states of transition metals,where electron transfer at the electrode produces catalysts with more valence states.Among these transition metal catalysts,electrochemical conversions catalyzed by inexpensive copper metals have received considerable attention.This article systematically investigated this field and reviewed the electrochemical copper catalytic methods applied in organic synthesis from the different activation modes of substrates,which can be broadly classified into the functionalization of C=C bonds,C-H bond activation,C-C and C-X bond activation,and so on. 展开更多
关键词 ELECTROCHEMISTRY Transition metal catalysis Copper catalysis Copper electrocatalysis
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W/V Dual-Atom Doping MoS_(2)-Mediated Phase Transition for Efficient Polysulfide Adsorption/Conversion Kinetics in Lithium-Sulfur Battery
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作者 Zhe Cui Ping Feng +2 位作者 Gang Zhong Qingdong Ou Mingkai Liu 《Nano-Micro Letters》 2026年第4期700-717,共18页
The dissolvable polysulfides and sluggish Li_2S conversion kinetics are acknowledged as two significant challenges in the application lithium-sulfur(Li-S)batteries.Herein,we introduce a dual-doping strategy to modulat... The dissolvable polysulfides and sluggish Li_2S conversion kinetics are acknowledged as two significant challenges in the application lithium-sulfur(Li-S)batteries.Herein,we introduce a dual-doping strategy to modulate the electronic structure of MoS_(2),thereby obtaining a multifunctional catalyst that serves as an efficient sulfur host.The W/V dual single-atomdoped MoS_(2)grown on carbon nanofibers(CMWVS)demonstrates a strong adsorption ability for lithium polysulfides,suppressing the shuttle effects.Additionally,the doping process also results in the phase transition from 2H-MoS_(2)to 1T-MoS_(2)and generates sufficient edge sulfur atoms,promoting the charge/electron transfer and enriching the reaction sites.All these merits contribute to the superior conversion reaction kinetics,leading to the outstanding Li-S battery performance.When fabricated as cathodes by compositing with sulfur,the CMWVS/S cathode delivers a high capacity of 1481.7 mAh g^(-1)at 0.1 C(1 C=1672 mAh g^(-1))and maintains 816.3 m Ah g^(-1)after 1000 cycles at 1.0 C,indicating outstanding cycling stability.Even under a high sulfur loading of 7.9 mg cm^(-2)and lean electrolyte conditions(E/S ratio of 9.0μL mg^(-1)),the cathode achieves a high areal capacity of 8.2 m Ah cm^(-2),showing great promise for practical Li-S battery applications.This work broadens the scope of doping strategies in transition-metal dichalcogenides by tailoring their electronic structures,providing insightful direction for the rational development of high-efficiency electrocatalysts for advanced Li-S battery applications. 展开更多
关键词 lithium-sulfur batteries ELECTROCATALYST Phase transition Dual single atoms Molybdenum disulfide
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Design of electrocaloric materials based on E–T phase diagrams
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作者 Fei Han Rongju Zhong +2 位作者 Jikun Yang Chuanbao Liu Yang Bai 《Chinese Physics B》 2026年第2期71-83,共13页
As electronic technology continues to evolve towards miniaturization and integration,the demand for micro-refrigeration technology in microelectronic systems is increasing.Ferroelectric(FE)refrigeration technology bas... As electronic technology continues to evolve towards miniaturization and integration,the demand for micro-refrigeration technology in microelectronic systems is increasing.Ferroelectric(FE)refrigeration technology based on the electrocaloric effect(ECE)has emerged as a highly promising candidate in this field,due to its advantages of high energy efficiency,simple structure,easy miniaturization,low cost,and environmental friendliness.The EC performance of FE materials essentially depends on the phase transition features under the coupled electric and thermal fields,making the E–T phase diagram a core tool for decoding the underlying mechanism of ECE.This paper reviews the development of EC materials,focusing on the comprehensive study of E–T phase diagrams.By correlating the microscopic phase structure of FE materials with the macroscopic physical properties,it clarifies the manipulation mechanism for enhanced ECE performance,providing theoretical support for the targeted design of high-performance EC materials.In the future,the introduction of data-driven methods is expected to enable the high-throughput construction of FE phase diagrams,thereby accelerating the optimization of high-performance EC materials and promoting the practical application of FE refrigeration technology. 展开更多
关键词 ferroelectric material electrocaloric effect phase diagram phase transition sold-state refrigeration
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Volume change and creep behaviors related to stress-phase transition path in methane hydrate-bearing silty sand
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作者 Jiazuo Zhou Qi Fan +1 位作者 Zhenyu Zhu Changfu Wei 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1526-1540,共15页
The volume change behavior of natural gas hydrate-bearing sediment is essential as it influences settlement,strength,and stiffness,which directly affect the stability of hydrate reservoirs during hydrate extraction or... The volume change behavior of natural gas hydrate-bearing sediment is essential as it influences settlement,strength,and stiffness,which directly affect the stability of hydrate reservoirs during hydrate extraction or in response to environmental changes.The volume change is influenced not only by stress but also by the formation and dissociation of hydrates.This study adopted a customized apparatus for one-dimensional compression tests,allowing independent control of gas pressure and effective stress.Tests were conducted on samples with different hydrate saturations along various temperature-gas pressure-effective stress paths,yielding some conclusions related to compressibility and creep.An unusual phenomenon was observed under low-stress conditions:hydrate formation led to shrinkage rather than expansion.Three potential mechanisms behind this occurrence were discussed.As hydrate saturation increases,the yield stress rises while the compression and swelling indexes remain minimally affected.After hydrate dissociation,the compression curve of hydrate-bearing sediment drops to that of hydrate-free sediment.Once hydrate is formed,the compression curve of hydrate-free sediment gradually approaches that of hydrate-bearing sediment during the subsequent loading.Under low-stress conditions,the creep of both hydrate-free and hydrate-bearing sediments is very weak.However,when stress increases,significantly beyond the yield stress,the creep of both sediments increases significantly,with hydrate-bearing sediment exhibiting much greater creep than hydrate-free sediment. 展开更多
关键词 Hydrate-bearing sediment Phase transition Volume change Creep behavior
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From perinodular to nodular tissues:aberrant accumulation of ornithine accelerates pulmonary fibrosis in silicosis
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作者 Ling Wang Shuxian Wang +4 位作者 Hongxin Li Shuting Wei Yiwei Shi Xuemei Qin Zhenyu Li 《Journal of Environmental Sciences》 2026年第1期424-436,共13页
Silicosis is one of the most serious and prevalent occupational diseases globally,characterized by typical silicotic nodules and fibrosis.Recent studies suggest that the perinodular zone of the lung shares certain cha... Silicosis is one of the most serious and prevalent occupational diseases globally,characterized by typical silicotic nodules and fibrosis.Recent studies suggest that the perinodular zone of the lung shares certain characteristics with the nodules themselves.In this study,a silicotic rat model was established via a single intratracheal in-stillation of a 50 mg/mL silica suspension.Pulmonary anatomical and pathological examinations revealed that silica deposition induced severe alterations in both the nodular and perinodular tissues.Subsequently,pseudo-targeted metabolomics analysis revealed that abnormally elevated ornithine levels were closely associated with the progression of silicosis,from normal to perinodular and finally to nodular tissues.Immunofluorescent stain-ing demonstrated that,in addition to M2 macrophages,silica exposure increased the protein levels of ARG1 in epithelial cells,a finding further confirmed by in vitro experiments using A549 and BEAS-2B cells.Moreover,accumulated ornithine induced epithelial-mesenchymal transition in vitro,increased extracellular matrix expres-sion in NIH 3T3 fibroblasts,and enhanced TGF-β1 levels in RAW264.7 cells.Co-exposure to ornithine and silica significantly induced the aberrant expression of fibrosis-associated proteins compared to silica exposure alone,characterized by increased levels of FN and𝛼-SMA,as well as decreased E-cad expression.These findings sug-gest that silica exposure up-regulates ARG1 in various cells,leading to ornithine accumulation,which in turn accelerates the progression of fibrosis. 展开更多
关键词 SILICOSIS Pseudotargeted metabolomics ORNITHINE Nodular and perinodular tissues Epithelial-mesenchymal transition
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Nanoreactor-Structured Defective MoS_(2):Suppressing Intercalation-Induced Phase Transitions and Enhancing Reversibility for Potassium-Ion Batteries
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作者 Chunrong Ma Cyrus Koroni +3 位作者 Jiacheng Hu Ji Qian Guangshuai Han Hui Xiong 《Nano-Micro Letters》 2026年第4期771-786,共16页
Conversion-type electrode materials hold significant promise for potassium-ion batteries(PIBs)due to their high theoretical capacities,yet their practical deployment is hindered by sluggish kinetics and irreversible s... Conversion-type electrode materials hold significant promise for potassium-ion batteries(PIBs)due to their high theoretical capacities,yet their practical deployment is hindered by sluggish kinetics and irreversible structural degradation.To overcome these limitations,we propose a rationally engineered nanoreactor architecture that stabilizes defect-rich MoS_(2)via interlayer incorporation of a carbon monolayer,followed by encapsulation within a nitrogen-doped carbon shell,forming a MoSSe@NC heterostructure.This tailored structure synergistically accelerates both K^(+)diffusion kinetics and electron transfer,enabling unprecedented rate performance(107 mAh g^(-1)at 10 Ag^(-1))and ultralong cyclability(86.5%capacity retention after 1200 cycles at 3 A g^(-1)).Mechanistic insights reveal a distinctive“adsorption-conversion”pathway,where sulfur vacancies on exposed S-Mo-S basal planes act as preferential K^(+)adsorption sites,effectively suppressing parasitic phase transitions during intercalation.In situ X-ray diffraction and transmission electron microscopy corroborate the structural reversibility of the conversion reaction,with the carbon matrix dynamically accommodating strain while preserving electrode integrity.This work not only advances the understanding of defect-driven interfacial chemistry in conversion-type materials but also provides a versatile strategy for designing high-performance anodes in next-generation PIBs through heterostructure engineering. 展开更多
关键词 Potassium ion batteries Phase transitions Structure reversibility Intercalated heterostructure Defect engineering
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Tracking a High-Tech Transition--How technology is powering Guangdong’s manufacturing transformation
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作者 HU FAN 《ChinAfrica》 2026年第1期30-32,共3页
The moment a media delegation from the Republic of the Congo arrived at the Othello Kitchenware Museum on 18 November 2025,they were greeted with a vivid show of Guangdong’s industrial strength.Standing before them w... The moment a media delegation from the Republic of the Congo arrived at the Othello Kitchenware Museum on 18 November 2025,they were greeted with a vivid show of Guangdong’s industrial strength.Standing before them was not a typical exhibition hall,but a building shaped like a gleaming stainless-steel cooking pot. 展开更多
关键词 othello kitchenware museum TECHNOLOGY industrial strength high tech transition guangdong manufacturing transformation
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Experimental investigation on trigger dynamics of molten droplet under external disturbance pressure during fuel-coolant interaction
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作者 He-Lin Chen Cheng Peng +2 位作者 Xian-Pin Meng Jian Deng Jiang Wu 《Nuclear Science and Techniques》 2026年第3期189-207,共19页
Fuel-coolant interaction(FCI)remains one of the most complex challenges in severe accident research,with the triggering process being a key aspect that may govern subsequent fine fragmentation and potential steam expl... Fuel-coolant interaction(FCI)remains one of the most complex challenges in severe accident research,with the triggering process being a key aspect that may govern subsequent fine fragmentation and potential steam explosions.In this study,the evolution characteristics of droplet-water interactions under external disturbance conditions were investigated using a self-designed FCI experimental setup.The experimental observations revealed that cavity formation reduced the drag force on the droplet,thereby increasing its peak velocity.However,the external disturbance pressure can disrupt the cavity,leading to a reduction in the droplet peak velocity.Furthermore,it was found that an increase in external disturbance pressure tended to increase the peak value of the droplet expansion rate,thereby promoting the fine-fragmentation process.This effect holds regardless of the initial droplet temperature,coolant temperature,or even when using droplet materials such as lead,which is generally considered unfavorable for steam explosions.Comparative analyses indicated that a higher external disturbance pressure may shorten the triggering time of the droplet surface and enhance the trigger intensity.These findings provide important phenomenological insights for further investigation of the triggering mechanisms in the initial stage of fuel-coolant interactions. 展开更多
关键词 External disturbance pressure Molten droplet Transit velocity Expansion rate Fuel-coolant interaction
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Strain energy enhanced room-temperature magnetocaloric effect in Mn_(5)Ge_(3)
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作者 Xiaohe Liu Ping Song +5 位作者 Sen Yao Yuhao Lei Ling Yang Shenxiang Du Yiran Deng Defeng Guo 《Chinese Physics B》 2026年第2期595-602,共8页
Large magnetic entropy change(△S_(M))can realize a prominent heat transformation under the magnetic field and directly strengthen the efficacy of the magnetocaloric effect,which provides a pioneering environmentally ... Large magnetic entropy change(△S_(M))can realize a prominent heat transformation under the magnetic field and directly strengthen the efficacy of the magnetocaloric effect,which provides a pioneering environmentally friendly solidstate strategy to improve refrigeration capacities and efficiencies.The second-order magnetic transition(SOMT)materials have broader△S_(M) peaks without thermal hysteresis,making them highly attractive in magnetic refrigeration,especially in the room temperature range.Here,we report a significant enhancement of△S_(M) at room temperature in single-crystal Mn_(5)Ge_(3).In this SOMT system,we realize a 60%improvement of-△S_(M)^(max) from 3.5 J/kg·K to 5.6 J/kg·K at T=300 K.This considerable enhancement of△S_(M) is achieved by intentionally introducing strain energy through high-pressure constrained deformation.Both experimental results and Monte Carlo simulations demonstrate that the enhancement of△S_(M) originates from the microscopic strain and lattice deformation induced by strain energy after deformation.This strain energy will reconstruct the energy landscape of this ferromagnetic system and enhance magnetization,resulting in a giant intensity of magnetocaloric responses.Our findings provide an approach to increase magnetic entropy change and may give fresh ideas for exploring advanced magnetocaloric materials. 展开更多
关键词 magnetocaloric effect magnetic entropy change second-order magnetic transition strain energy DEFORMATION
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Detonation characteristics of the solid-liquid mixed fuel cloud of Al/B/MgH_(2)/DEE/IPN
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作者 Zhangjun Wu Xianzhao Song +4 位作者 Shuxin Deng Bingbing Yu Yongxu Wang Rhoda Afriyie Mensah Suning Mei 《Defence Technology(防务技术)》 2026年第1期377-388,共12页
To elucidate the dispersion and explosion characteristics of multi-metal powder and liquid composite fuel formulations,high-energy metal powders(aluminum(Al),boron(B),and magnesium hydride(MgH_(2)))are incorporated in... To elucidate the dispersion and explosion characteristics of multi-metal powder and liquid composite fuel formulations,high-energy metal powders(aluminum(Al),boron(B),and magnesium hydride(MgH_(2)))are incorporated into a liquid fuel primarily composed of diethyl ether(DEE)and isopropyl nitrate(IPN).The explosion characteristics of different solid-liquid fuel-air-explosive(FAE)under unconfined conditions are investigated using a high-speed camera,infrared thermal imaging,and a pressure measurement system.Results demonstrate that high-energy metal powders significantly enhance detonation energy dissipation,with aluminum exhibiting the most pronounced effect.Fuel 5#(45.4 wt%DEE,9.2 wt%IPN,29.5 wt%Al,9.1 wt%B,6.8 wt%MgH_(2))exhibits superior explosion performance,achieving higher values of overpressure,impulse,and thermal radiation damage during the detonation stage compared to other fuels.However,Fuel 5#also displays faster decay rates,attributed to accelerated heat release rates induced by B and MgH_(2)powders.This study reveals that different metal powders in solid-liquid FAE exhibit distinct enhancements in explosion performance,providing critical insights for optimizing composite fuel design. 展开更多
关键词 Detonable aerosol OVERPRESSURE Shock wave Deflagration to detonation transition Temperature field
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Tetrahedral framework nucleic acid loaded celastrol ameliorates skin fibrosis by epithelial-mesenchymal transition prevention
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作者 Junxin Cheng Zhongyi Fang +2 位作者 Runqiao Yang Yunfeng Lin Sirong Shi 《Science China Materials》 2026年第3期1786-1796,共11页
Progressive skin fibrosis ultimately results in irreversible contractures,causing both joint dysfunction and cosmetic deformity.The key pathological features of skin fibrosis include persistent inflammation and abnorm... Progressive skin fibrosis ultimately results in irreversible contractures,causing both joint dysfunction and cosmetic deformity.The key pathological features of skin fibrosis include persistent inflammation and abnormal accumulation of the extracellular matrix(ECM),with epithelialmesenchymal transition(EMT)playing a critical role in disease progression.However,current therapeutic strategies for cutaneous fibrosis are largely palliative and often require repeated interventions,with limited efficacy.Celastrol(Cel)exerts anti-inflammatory and anti-fibrotic effects in skin tissue,but its clinical application is limited by poor bioavailability and a narrow therapeutic window.Tetrahedral framework nucleic acid(tFNA),a novel nanocarrier system,exhibits multiple advantages,including enhanced cellular uptake,improved cell viability,and intrinsic anti-fibrotic and anti-inflammatory properties.Therefore,this study applied tFNA-Cel complex(TCC)as an advanced nanotherapeutic agent,designed to exert a synergistic anti-fibrotic effect.In this study,an in vitro model of skin fibrosis was established using human keratinocyte(HaCaT)cells treated with 5 ng mL^(-1) transforming growth factor beta(TGF-β)for 24 h.The results showed that TCC significantly inhibited EMT progression by reducingα-smooth muscle actin(α-SMA)levels and increasing E-cadherin level.Compared to tFNA or Cel alone,TCC exhibited superior anti-fibrotic effects in the fibrosis model,as evidenced by modulation of SMAD family member 2(SMAD2)signaling and collagen I expression.Furthermore,the TCC group showed lower levels of nuclear factorκB p65(NF-κB p65),BCL-2-associated X protein(Bax),and reactive oxygen species(ROS)compared to the Cel or tFNA groups.These findings highlight TCC as a promising treatment for skin fibrosis,with its synergistic anti-fibrotic effects providing new therapeutic avenues. 展开更多
关键词 tetrahedral framework nucleic acids CELASTROL skin fibrosis nanodrug delivery system epithelial-mesenchymal transition
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