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High-Entropy Materials:A New Paradigm in the Design of Advanced Batteries
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作者 Yangmei Xin Minmin Zhu +1 位作者 Haizhong Zhang Xinghui Wang 《Nano-Micro Letters》 2026年第1期1-52,共52页
High-entropy materials(HEMs)have attracted considerable research attention in battery applications due to exceptional properties such as remarkable structural stability,enhanced ionic conductivity,superior mechanical ... High-entropy materials(HEMs)have attracted considerable research attention in battery applications due to exceptional properties such as remarkable structural stability,enhanced ionic conductivity,superior mechanical strength,and outstanding catalytic activity.These distinctive characteristics render HEMs highly suitable for various battery components,such as electrodes,electrolytes,and catalysts.This review systematically examines recent advances in the application of HEMs for energy storage,beginning with fundamental concepts,historical development,and key definitions.Three principal categories of HEMs,namely high-entropy alloys,high-entropy oxides,and highentropy MXenes,are analyzed with a focus on electrochemical performance metrics such as specific capacity,energy density,cycling stability,and rate capability.The underlying mechanisms by which these materials enhance battery performance are elucidated in the discussion.Furthermore,the pivotal role of machine learning in accelerating the discovery and optimization of novel high-entropy battery materials is highlighted.The review concludes by outlining future research directions and potential breakthroughs in HEM-based battery technologies. 展开更多
关键词 high entropy alloys high entropy oxides high entropy MXenes high entropy battery materials Machine learning
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Bio-based furan aramid/ceramic-coated lithium-ion battery separators with high ionic conductivity,wettability and safety via in situ lithium compensation strategy
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作者 Jitao Zhu Lei Huang +8 位作者 Lizhi Xu Yuting Chu Wenyan Zhang Deguang Liu Zhuo Ke Hai Xu Yezi You Chuang Li Yao Fu 《Journal of Energy Chemistry》 2026年第3期630-638,共9页
The structural design and performance characteristics of the diaphragm have a decisive impact on the safety and electrochemical performance of lithium-ion batteries(LIBs).However,traditional polyolefin diaphragms stil... The structural design and performance characteristics of the diaphragm have a decisive impact on the safety and electrochemical performance of lithium-ion batteries(LIBs).However,traditional polyolefin diaphragms still face challenges in simultaneously improving the ion transport efficiency and thermal stability.Here,we report an in situ dynamic lithium compensation strategy for manufacturing a biobased furan aramid/ceramic diaphragm(BAS)with higher thermal stability and ion transport efficiency.Specifically,exchangeable carboxyl groups(–COOH)are introduced into the bio-based furan aramid(BA)framework,which are in situ converted into–COOLi groups to form lithium ions(Li^(+))transport channels,achieving dynamic compensation of active Li^(+).The dual transmission system of ion exchange and physical pore channels synergistically enhances the ionic conductivity of BAS to 1.536 mS cm^(-1).The high polarity structure of the furan ring and the electrolyte have excellent compatibility,significantly reducing the solid–liquid interfacial energy,making BAS have extremely high electrolyte wettability(contact angle of 0°).The BA amide group forms a multi-scale bonding network with the nano-ceramics.The BAS prepared by the water-coating process exhibits excellent thermal stability(with a thermal shrinkage rate of less than 1%after 1 h at 150℃).The LiFePO_(4)|Li half-cell assembled with BAS shows a capacity retention rate of up to 91.7%after 280 cycles at 1C,with a Coulomb efficiency of 99%,demonstrating excellent cycling stability.This design and development based on bio-materials provides a new approach for high safety and high energy density battery systems. 展开更多
关键词 Battery separator Bio-based furan aramid high ionic conductivity high electrolyte wettability Thermal stability
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Achieving high entropy in rare earth oxides:A detailed experimental procedure
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作者 Ye Cheng Ehsan Ghasali +7 位作者 Saleem Raza Asif Hayat Ming Liu Junsheng Ye Pengfei Zhang Andrii Babenko Jie Li Yasin Orooji 《Journal of Rare Earths》 2026年第3期900-909,I0006,共11页
This study explored the impact of sintering time and temperature on the synthesis and formation of high-entropy rare earth oxides(HEOs).By systematically varying the sintering conditions,a series of Lu_(2)Yb_(2)Tm_(2)... This study explored the impact of sintering time and temperature on the synthesis and formation of high-entropy rare earth oxides(HEOs).By systematically varying the sintering conditions,a series of Lu_(2)Yb_(2)Tm_(2)Er_(2)O_(12) samples was synthesized and their structural and chemical properties were analyzed using scanning electron microscopy(SEM)with energy-dispersive X-ray spectroscopy(EDS)elemental mapping,X-ray diffraction(XRD),high-resolution transmission electron microscopy(HRTEM),and X-ray photoelectron spectroscopy(XPS).According to XRD patterns,a single-phase cubic C-type structure is easier to form at higher sintering temperatures(1400-1500℃),with sharper peaks signifying better crystallinity.With longer sintering times improving grain development and homogeneity,SEM research reveals a change in morphology from spherical grains at lower temperatures(1100-1200℃)to blocky grains at higher temperatures(1300-1500℃).HRTEM pictures verified the nanoparticles'strong crystallinity,and at higher temperatures,the lattice fringes widen and become more distinct,indicating better atomic ordering and diffusion.Stable and uniform high-entropy oxide production is indicated by the XPS spectra,which shows uniform elemental distribution and consistent chemical states of the constituent elements with very slight variations in the oxygen peaks.The findings highlight how important the sintering temperature is for reaching the intended high-entropy phase,with higher temperatures promoting improved atomic diffusion and compositional homogeneity.The results open the door for the use of high-entropy rare earth oxides in sophisticated functional materials by offering insightful information on how to best synthesize them. 展开更多
关键词 high entropy oxides Rare earths Sintering parameters high energy milling
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Femtosecond laser-induced sub-50-nm period nanogratings with ultrahigh uniformity on graphite under water immersion
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作者 Qingyu Li Feng Zhou Min Huang 《International Journal of Extreme Manufacturing》 2026年第1期573-600,共28页
Laser-induced periodic surface structures(LIPSS)have gained increasing attention in the field of micro/nano fabrication,although achieving sub-100-nm period LIPSS with high uniformity remains a significant challenge.I... Laser-induced periodic surface structures(LIPSS)have gained increasing attention in the field of micro/nano fabrication,although achieving sub-100-nm period LIPSS with high uniformity remains a significant challenge.In this work,towards deep-subwavelength LIPSS on highly oriented pyrolytic graphite(HOPG),we demonstrate that ultra-uniform nanogratings of sub-50-nm periods and near-10-nm groove widths can be stably prepared via 800-nm femtosecond laser scanning irradiation with a high-NA objective lens under water immersion.The resulting nanogratings of strong polarization dependence,exhibiting exceptional surface flatness,period stability,and structural integrity,tend to appear at near-damage-threshold fluence regime with an appropriate effective pulse number.It turns out that the water immersion condition can significantly reduce the thermal effects of femtosecond laser ablation on HOPG,and thus via a mild,incubation-like scanning ablation process occurring in the nanogrooves with a continuous or jumping manner,this deep-subwavelength grating can achieve robust elongation growth,ensuring its long-range uniformity as well as minimal deposited debris and structural defects.Interestingly,the different incubation extension mechanisms for the mutually perpendicular and parallel settings between scanning direction and laser polarization bring not only distinct effective-pulse-number windows and somewhat different grating qualities,but also different extension stabilities in nanograting stitching via overlapping scanning lines and thus the optimal scanning strategy of parallel setting for large-area processing.In short,this study presents a convenient laser-processing approach for high precision fabrication of sub-50-nm gratings on HOPG,which would provide new insights into micro/nano-fabrication for optoelectronic metasurfaces and physics of the interaction between ultrafast laser and graphite. 展开更多
关键词 deep-subwavelength grating femtosecond laser processing water immersion ultrahigh uniformity highly oriented pyrolytic graphite
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3D printed high-temperature ceramic conformal array antenna:Design,analysis,manufacturing,and testing
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作者 Peng Li Ruibo Li +5 位作者 Zijiao Fan Jiujiu Han Guangda Ding Qunbiao Wang Wanye Xu Paolo Rocca 《Defence Technology(防务技术)》 2026年第1期340-353,共14页
In this study,the design,analysis,manufacturing,and testing of a 3D-printed conformal microstrip array antenna for high-temperature environments is presented.3D printing technology is used to fabricate a curved cerami... In this study,the design,analysis,manufacturing,and testing of a 3D-printed conformal microstrip array antenna for high-temperature environments is presented.3D printing technology is used to fabricate a curved ceramic substrate,and laser sintering and microdroplet spraying processes are used to add the conductive metal on the curved substrate.The problems of gain loss,bandwidth reduction,and frequency shift caused by high temperatures are addressed by using a proper antenna design,with parasitic patches,slots,and metal resonant cavities.The antenna prototype is characterized by the curved substrates and the conductive metals for the power dividers,the patch,and the ground plane;its performance is examined up to a temperature of 600℃in a muffle furnace and compared with the results from the numerical analysis.The results show that the antenna can effectively function at 600℃and even higher temperatures. 展开更多
关键词 Ceramic antenna Conformal array high-temperature environment 3D printing high gain and wide band
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Study on the damage mechanism of high chromia refractory in the slag tapping hole of commercial entrained-flow gasifier
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作者 PENG Baozi LIU Zhen +4 位作者 BAI Jin LI Huaizhu SUN Kaidi AN Haiquan LI Jun 《燃料化学学报(中英文)》 北大核心 2026年第3期170-179,共10页
The service life of refractory brick in the slag tapping hole of gasifiers is a significant concern for long-term and stable operation.This study examined the damage mechanism of high chromia refractory of four commer... The service life of refractory brick in the slag tapping hole of gasifiers is a significant concern for long-term and stable operation.This study examined the damage mechanism of high chromia refractory of four commercial coal-water slurry gasifiers with their corresponding gasification coal samples and the corroded refractory bricks in the slag tapping hole of the gasifier.The slag characteristic,including crystallization and viscosity-temperature of four gasification coal samples were analyzed.The results revealed that the low viscosity slag could lead to more severe damage to refractory bricks.Given the risk of slag crystallization,it is recommended to establish a safe slag tapping temperature range should be set as tICT(initial crystallization temperature)−t_(2.5) when tICT is higher than t_(25).Upon examining interior morphology of these corroded refractory bricks,some cracks were observed within them.The chemical composition of molten slag was analyzed using SEM-EDS.However,XRD results found no spinel containing zirconium in these cracks.This suggests that the emergence of these cracks are mainly attributed to the molten slag penetration and the subsequent reaction with the refractory material.The difference in thermal expansion between the newly formed substances and refractory material is critical in forming these cracks.Furthermore,SEM-EDS analysis was also conducted on the slag-aggregate and the slag-matrix interface.The results reveal that the reduction in Cr_(2)O_(3) content is the earliest characteristic of damage in high chromia refractories.A proposed damage mechanism of refractory brick suggests that the matrix and aggregate of high chromia refractory are initially compromised because of the reduced Cr_(2)O_(3) content.Subsequently,the molten slag penetrates the interior of the refractory brick,forming new substances,leading to damage caused by the difference in thermal expansion between the new substances and the refractory brick.Understanding and preventing the reduction of Cr_(2)O_(3) content is vital to prolonging the service life of refractory brick in the slag tapping hole of the gasifier based on this damage mechanism. 展开更多
关键词 GASIFICATION high chromia refractory SLAG damage mechanism corrosion
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Research Status and Prospects of Platinum Group Metal Coatings with High-Temperature Oxidation Resistance
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作者 Ding Chenxi Liu Zhongyu +3 位作者 Fang Zhen Wang Haoxu Lv Biao Hu Zhenfeng 《稀有金属材料与工程》 北大核心 2026年第2期333-344,共12页
Platinum group metals have high melting points,strong corrosion resistance,stable chemical properties,and low oxygen permeability in high-temperature oxygen-containing environments.As thermal protective coating materi... Platinum group metals have high melting points,strong corrosion resistance,stable chemical properties,and low oxygen permeability in high-temperature oxygen-containing environments.As thermal protective coating materials,they have gained essential applications in the aerospace field and have excellent prospects for application in frontier military fields,such as protecting hot-end components of hypersonic aircraft.This research reviewed the latest research progress of platinum group metal coatings with hightemperature oxidation resistance,including coating preparation techniques,oxidation failure,and alloying modification.The leading preparation techniques of current platinum group metal coatings were discussed,as well as the advantages and disadvantages of various existing preparation techniques.Besides,the intrinsic properties,failure forms,and failure mechanisms of coatings of single platinum group metal in high-temperature oxygen-containing environments were analyzed.On this basis,the necessity,main methods,and main achievements of alloying modification of platinum group metals were summarized.Finally,the future development of platinum group coatings with high-temperature oxidation resistance was discussed and prospected. 展开更多
关键词 platinum group metal coatings preparation technique high temperature oxidation resistance alloying modification
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GcH1 contributes to high-altitude adaptation in Tibetans by regulating blood nitric oxide
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作者 Yongbo Guo Wangshan Zheng +6 位作者 Tian Yue Baimakangzhuo Xuebin Qi Kai Liu Liya Li Yaoxi He Bing Su 《Journal of Genetics and Genomics》 2026年第1期97-109,共13页
Nitric oxide(NO)is a key vasodilator that regulates vascular pressure and blood flow.Tibetans have developed a"blunted"mechanism for regulating NO levels at high altitude,with GTP cyclohydrolase 1(GCH1)ident... Nitric oxide(NO)is a key vasodilator that regulates vascular pressure and blood flow.Tibetans have developed a"blunted"mechanism for regulating NO levels at high altitude,with GTP cyclohydrolase 1(GCH1)identified as a key candidate gene.Here,we present comprehensive genetic and functional analyses of GCH1,which exhibits strong Darwinian positive selection in Tibetans.We show that Tibetan-enriched GCH1 variants down-regulate its expression in the blood of Tibetans.Based on this observation,we generate the heterozygous Gch1 knockout(Gch1^(+/-))mouse model to simulate its downregulation in Tibetans.We find that under prolonged hypoxia,the Gch1^(+/-)mice have relatively higher blood NO and blood oxygen saturation levels compared with the wild-type(WT)controls,providing better oxygen supplies to the cardiovascular and pulmonary systems.Markedly,hypoxia-induced cardiac hypertrophy and pulmonary remodeling are significantly attenuated in the Gch1^(^(+/-))mice compared with the WT controls,likely due to the adaptive changes in molecular regulations related to metabolism,inflammation,circadian rhythm,extracellular matrix,and oxidative stress.This study sheds light on the role of GCH1 in regulating blood NO,contributing to the physiological adaptation of the cardiovascular and pulmonary systems in Tibetans at high altitude. 展开更多
关键词 GCH1 Nitric oxide Tibetans high altitude HYPOXIA ADAPTATION
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Design and optimization of a high-efficiency current-biased reverse load modulated power amplifier with impedance and performance constraints
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作者 Zhongpeng NI Heng ZHANG +4 位作者 Jing XIA Wence ZHANG Wa KONG Chao YU Xiaowei ZHU 《ENGINEERING Information Technology & Electronic Engineering》 2026年第1期71-79,共9页
We propose an optimization method based on evolutionary computation for the design of broadband high-efficiency current-biased reverse load-modulation power amplifiers(CB-RLM PAs).First,given the reverse load-modulati... We propose an optimization method based on evolutionary computation for the design of broadband high-efficiency current-biased reverse load-modulation power amplifiers(CB-RLM PAs).First,given the reverse load-modulation characteristics of CB-RLM PAs,a comprehensive objective function is proposed that combines multi-state impedance trajectory constraints with in-band performance deviations.For the saturation and 6 dB power back-off(PBO)states,approximately optimal impedance regions on the Smith chart are derived using impedance constraint circles based on load-pull simulations.These regions are used together with in-band performance deviations(e.g.,saturated efficiency,6 dB PBO efficiency,and saturated output power)for matching network optimization and design.Second,a multi-objective evolutionary algorithm based on decomposition with adaptive weights,neighborhood,and global replacement is integrated with harmonic balance simulations to optimize design parameters and evaluate performance.Finally,to validate the proposed method,a broadband CB-RLM PA operating from 0.6 to 1.8 GHz is designed and fabricated.Measurement results show that the efficiencies at saturation,6 dB PBO,and 8 dB PBO all exceed 43.6%,with saturated output power being maintained at 40.9–41.5 dBm,which confirms the feasibility and effectiveness of the proposed broadband high-efficiency CB-RLM PA optimization and design approach. 展开更多
关键词 Current-biased reverse load-modulation Broadband high efficiency Power amplifier Optimization
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Strong yet Flexible TiC-SiC Fibrous Membrane with Long-Time Ultrahigh Temperature Resistance for Sensing in Extreme Environment
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作者 Tianyue Yang Yan Shen +5 位作者 Yangzhong Zhao Zhongqian Zhao Xue Zhou Qianji Chen Xujing Wang Yanzi Gou 《Nano-Micro Letters》 2026年第6期16-29,共14页
The demand for sensors capable of operating in extreme environment of the fields,such as aerospace vehicles,aeroengines and fire protection,is rapidly increasing.However,developing flexible ceramic fibrous pressure se... The demand for sensors capable of operating in extreme environment of the fields,such as aerospace vehicles,aeroengines and fire protection,is rapidly increasing.However,developing flexible ceramic fibrous pressure sensors that combine high temperature stability with robust mechanical properties remains a significant challenge.Herein,through precise multi-scale process control,high-strength(2.1 MPa)TiC-SiC flexible fibrous membrane is successfully fabricated.The membrane exhibits exceptional thermal resistance(2000℃)and long–term thermal stability(1800℃ for 5 h)in the inert atmosphere.Meanwhile,the TiC-SiC fibrous membrane shows excellent oxidation resistance and still achieves strength of 1.8 MPa after being oxidized at 1200℃ for 1 h in air.Remarkably,TiC-SiC fibrous membrane withstands a load of approximately 1400 times its own weight and the ablation of butane flame(~1300℃)for at least 1 h without breaking.Notably,after heat treatment at 1800℃ for 5 h in an argon atmosphere,the TiC-SiC fibrous membrane even sustains pressure–sensing performance for up to 300 cycles.The membrane exhibits stable resistivity up to 900℃ and shows sensing stability under butane flame.The results of this work provide an effective and feasible solution to fill the research gap of flexible fibrous sensors for extreme environments. 展开更多
关键词 TiC-SiC Fibrous membrane FLEXIBILITY high temperature stability Pressure sensing
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Broadband polarization-based method for color high-resolution imaging through complex scattering media
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作者 Sen Wang Tianyu Wang +7 位作者 Piao He Yan Hui Xue Dong Jinpeng Liu Jingjing Ge Fei Liu Meng Xiang Xiaopeng Shao 《Advanced Photonics Nexus》 2026年第1期236-247,共12页
In complex media scattering,multiple scattering severely degrades the optical wavefront and results in blurred images,while the spectral distortion caused by the scattering effect leads to severe color distortion.Achi... In complex media scattering,multiple scattering severely degrades the optical wavefront and results in blurred images,while the spectral distortion caused by the scattering effect leads to severe color distortion.Achieving color high-resolution imaging through scattering media remains a significant challenge.Here,we propose a broadband,polarization-based method for color high-resolution imaging through scattering media.This approach enables high-resolution reconstruction by effectively separating the speckle illumination pattern from the mixed-scattering field information,leveraging polarization common-mode characteristics.Concurrently,it incorporates chromatic balance compensation to correct spectral aliasing in the scattered light field,enabling color high-resolution imaging through complex scattering media.To further optimize color distortion caused by scattering,a compensation strategy combining color constancy and white balance theory is adopted.Experimental results demonstrate that the proposed method significantly enhances both spatial resolution and color fidelity across various scattering conditions and target materials,showcasing strong adaptability and robustness.This approach provides an effective solution for achieving high-resolution color optical imaging in complex scattering environments. 展开更多
关键词 scattering medium color imaging POLARIZATION high resolution
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Thermo-mechanical damage behavior of the interface between hybrid alkali-resistant glass fiber-reinforced concrete and rock under high and variable temperature conditions
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作者 Cong Zhang Zhen Xu +4 位作者 Shanyong Wang Chong Shi Hui Wang Yonggang Zhang Guoqing Chen 《International Journal of Mining Science and Technology》 2026年第2期399-421,共23页
Thermal-mechanical damage and deformation at the interface between shotcrete linings and the surrounding rock of tunnels under high-temperature and variable-temperature conditions are critical to the safe construction... Thermal-mechanical damage and deformation at the interface between shotcrete linings and the surrounding rock of tunnels under high-temperature and variable-temperature conditions are critical to the safe construction and operation of tunnel engineering.This study investigated the thermo-mechanical damage behavior of the composite interface between alkali-resistant glass fiber-reinforced concrete(ARGFRC)and granite,focusing on a plateau railway tunnel.Laboratory triaxial tests,laser scanning,XRD analysis,numerical simulations,and theoretical analyses were employed to investigate how different initial curing temperatures and joint roughness coefficient(JRC)influence interfacial damage behavior.The results indicate that an increase in interface roughness exacerbates the structural damage at the interface.At a JRC of 19.9 and a temperature of 70℃,crack initiation in granite was notably restrained when the confining pressure rose from 7 MPa to 10 MPa.Roughness-induced stress distribution at the interface was notably altered,although this effect became less pronounced under high confining pressure conditions.Additionally,during high-temperature curing,thermal stress concentration at the tips of micro-convex protrusions on the granite surface induced microcracks in the adjacent ARGFRC matrix,followed by deformation.These findings provide practical guidelines for designing concrete support systems to ensure tunnel structural safety in high-altitude regions with harsh thermal environments. 展开更多
关键词 high and variable temperature ARGFRC-granite INTERFACE Thermo-mechanical coupling Damage evolution
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Prioritized Na^(+)Adsorption-Driven Cationic Electrostatic Repulsion Enables Highly Reversible Zinc Anodes at Low Temperatures
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作者 Guanchong Mao Pan Xu +4 位作者 Xin Liu Xingyu Zhao Zexiang Shen Dongliang Chao Minghua Chen 《Nano-Micro Letters》 2026年第2期306-319,共14页
Aqueous zinc metal batteries(AZMBs)are promising candidates for renewable energy storage,yet their practical deployment in subzero environments remains challenging due to electrolyte freezing and dendritic growth.Alth... Aqueous zinc metal batteries(AZMBs)are promising candidates for renewable energy storage,yet their practical deployment in subzero environments remains challenging due to electrolyte freezing and dendritic growth.Although organic additives can enhance the antifreeze properties of electrolytes,their weak polarity diminishes ionic conductivity,and their flammability poses safety concerns,undermining the inherent advantages of aqueous systems.Herein,we present a cost-effective and highly stable Na_(2)SO_(4)additive introduced into a Zn(ClO_(4))2-based electrolyte to create an organic-free antifreeze electrolyte.Through Raman spectroscopy,in situ optical microscopy,densityfunctional theory computations,and molecular dynamics simulations,we demonstrate that Na+ions improve low-temperature electrolyte performance and mitigate dendrite formation by regulating uniform Zn^(2+)deposition through preferential adsorption and electrostatic interactions.As a result,the Zn||Zn cells using this electrolyte achieve a remarkable cycling life of 360 h at-40℃ with 61% depth of discharge,and the Zn||PANI cells retained an ultrahigh capacity retention of 91%even after 8000 charge/discharge cycles at-40℃.This work proposes a cost-effective and practical approach for enhancing the long-term operational stability of AZMBs in low-temperature environments. 展开更多
关键词 Low-temperature resistant Organic-free additive Aqueous batteries high stability
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Mechanical property variation mechanisms of granite subjected to real-time high temperatures and subsequent cooling treatment
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作者 Rui Pang Dehao Meng +6 位作者 Thomas Frühwirt Hao Liu Yanan Zhao Qingyou Zhu Wengang Dang Mohamed Ismael Fei Wang 《Deep Underground Science and Engineering》 2026年第1期277-295,共19页
During geothermal resource exploitation,the potential deterioration of mechanical properties in high-temperature granite subjected to cooling poses a significant safety concern.To address this,the present study invest... During geothermal resource exploitation,the potential deterioration of mechanical properties in high-temperature granite subjected to cooling poses a significant safety concern.To address this,the present study investigates the coupled thermo-mechanical behavior of granite during heating and cooling through a combination of laboratory tests and finite difference method analysis.Initial investigations involve X-ray diffraction,thermal expansion test,thermogravimetric analysis,and uniaxial compression test.Results show the significant variations of granite properties under different thermal conditions,attributed to temperature gradients,water evaporation,and mineral phase transitions.Subsequently,a model considering temperature-dependent parameters and real-time cooling rates was employed to simulate linear heating and nonlinear cooling processes.Simulation results indicate that the thermal cracking predominantly occurs during the heating stage,with tensile failure as the primary mode.Additionally,a faster real-time cooling rate at higher temperatures intensifies the thermal cracking behavior in granite.This study effectively elucidates the thermomechanical coupling behavior of granite during heating and cooling processes,providing insights into the mechanisms of mechanical property changes with rising or decreasing temperatures. 展开更多
关键词 GRANITE nonlinear cooling real-time high temperature thermal cracking thermo-mechanical coupling
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Micromechanic view on influence of thermal treatment and real-time high temperature on the uniaxial compressive properties of granite
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作者 CAI Qi-jin MENG Fan-zhen +5 位作者 WEN Yuan-tao YUE Zhu-feng ZHANG Jun-nan LIU Peng-yuan XU Zheng-yang CHEN Jing 《Journal of Central South University》 2026年第1期422-441,共20页
The effect of real-time high temperature and thermal treatment on the mechanical characteristics and crack evolution of granite with different grain sizes(i.e.,0.5 mm,0.7 mm and 1.0 mm)is investigated by numerical sim... The effect of real-time high temperature and thermal treatment on the mechanical characteristics and crack evolution of granite with different grain sizes(i.e.,0.5 mm,0.7 mm and 1.0 mm)is investigated by numerical simulation employing a grain-based model,and the impact of initial cracks on thermal-induced strengthening is also examined by integrating random cracks within the model before tests.The results revealed that thermal stress,induced by the mismatch in thermal expansion coefficient between various minerals,is the primary distinction between rock specimens in real-time high temperature and thermal treatment.With increasing temperature,the thermal stress gradually accumulates in quartz minerals under real-time high temperature but releases after thermal treatment.The high local contact force significantly affects the peak stress and crack evolution.Uniaxial compression simulation results demonstrate that progressive accumulation of thermal stress induces degradation in macroscopic peak strength and increase of microcrack density.The grain size controls the ratio of intergranular contacts to intragranular contacts,and leads to an increase in strong contact number in the intragrain and a decrease in strong contact number in the intergrain.The strengthening of uniaxial compression strength in the experiment can be well simulated by controlling the number of pre-existing initial cracks in the numerical model.Our conclusions are beneficial to a better understanding of the underlying mechanisms of thermal damage and thermal strengthening of granite for deep geological engineering. 展开更多
关键词 high temperature thermal damage numerical simulation grain-based model thermal strengthening
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Spikelet Filling Characteristics in Early-Season Rice Experiencing High Temperatures during Ripening
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作者 Jiazhou Li Mingyu Zhang +5 位作者 Xing Li Fangbo Cao Jiana Chen Weiqin Wang Huabin Zheng Min Huang 《Phyton-International Journal of Experimental Botany》 2026年第1期251-264,共14页
Spikelet filling characteristics in early-season rice in southern China may be distinctive due to its exposure to high temperatures during the ripening period.However,limited information is currently available on thes... Spikelet filling characteristics in early-season rice in southern China may be distinctive due to its exposure to high temperatures during the ripening period.However,limited information is currently available on these characteristics.This study aimed to characterize spikelet filling in early-season rice and identify the key factors contributing to its improvement.Field experiments were conducted over two years(2021 and 2022)to mainly investigate the proportions of fully-filled,partially-filled,and empty spikelets,along with the biomass-fertilized spikelet ratio and harvest index,in 11 early-season rice varieties.The results revealed significant varietal variation in spikelet filling,with the proportion of fully-filled spikelets ranging from 60.6%to 81.1%in 2021 and from 66.3%to 79.2%in 2022.Among the 11 varieties,Liangyou 42,Lingliangyou 942,and Liangyou 287 exhibited relatively superior performance in spikelet filling.Linear regression revealed that,although a significant negative relationship existed between the proportion of fully-filled spikelets and both partially-filled and empty spikelets,the relationship with partially-filled spikelets was stronger.Additionally,the proportion of fully-filled spikelets showed a significant positive relationship with the harvest index but not with the biomass-fertilized spikelet ratio.These findings indicate that increasing the harvest index and reducing the occurrence of partially-filled grains are essential strategies for improving spikelet filling in early-season rice. 展开更多
关键词 high temperature RICE spikelet filling
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Synthesis of Polydicyclopentadiene Thermosets with High Stretchability and Self-healing Properties via Ring-opening Metathesis Polymerization
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作者 Wu Li Cheng-Yang Ban +4 位作者 Yu-Hao Xiong Da-Wei Zhang You-Gui Li Meng-He Xu Gui-Fu Si 《Chinese Journal of Polymer Science》 2026年第4期1083-1089,I0015,共8页
Thermosetting polymers exhibit outstanding mechanical properties,thermal stability,and chemical resistance due to their permanently cross-linked network structures.However,the irreversible nature of covalent cross-lin... Thermosetting polymers exhibit outstanding mechanical properties,thermal stability,and chemical resistance due to their permanently cross-linked network structures.However,the irreversible nature of covalent cross-linking renders these materials non-reprocessable and non-recyclable,posing significant environmental challenges.Although healable polymers based on dynamic covalent bonds and supramolecular interactions have emerged as promising alternatives,a broadly applicable strategy utilizing metal-ligand coordination in thermoset systems remains underexplored.In this work,we present a robust and healable thermoset system fabricated via ring-opening metathesis polymerization(ROMP)of commercially available chelating norbornene comonomers.Cross-linking is accomplished through O-donor coordination to Lewis acidic metal centers,yielding polydicyclopentadiene(PDCPD)-based networks that demonstrate high mechanical strength(up to 60.8 MPa)and effective self-healing performance.This methodology offers a simple and scalable approach to developing high-performance,sustainable thermosetting materials. 展开更多
关键词 Polydicyclopentadien Ring-opening metathesis polymerization high Stretchability Self-healing properties
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Cognitive behavioral therapy enhances psychological and physiological outcomes in high-altitude respiratory patients
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作者 De-Feng Meng Dong-You Zhang +3 位作者 Fan Yang Peng-Li Meng Ting-Ting Wen Yu-Zhao Wang 《World Journal of Psychiatry》 2026年第1期212-220,共9页
BACKGROUND Due to the dry and cold climate,the obvious temperature difference between day and night,and the low oxygen content of the air in the plateau area,people are prone to upper respiratory tract diseases,and of... BACKGROUND Due to the dry and cold climate,the obvious temperature difference between day and night,and the low oxygen content of the air in the plateau area,people are prone to upper respiratory tract diseases,and often the condition is prolonged,and the patients are prone to anxiety and uneasiness,which may be related to the harshness of the plateau environment,somatic discomfort due to the lack of oxygen,anxiety about the disease,and other factors.AIM To investigate the effects of cognitive behavioral therapy(CBT)on anxiety,sleep disorders,and hypoxia tolerance in patients with high-altitude respiratory diseases.METHODS A total of 2337 patients with high-altitude-related respiratory diseases treated at our hospital between November 2023 and January 2024 were selected as the study subjects.The subjects’pre-high-altitude residential altitude was approximately 1700 meters.They were divided into two groups.Both groups were given symptomatic treatment,and the control group implemented conventional nursing intervention,while the research group simultaneously conducted CBT intervention;assessed the degree of health knowledge of the two groups,and applied the Hamilton Anxiety Scale and the Pittsburgh Sleep Quality Index to assess the anxiety and sleep quality of the patients before and after the intervention,respectively.It also observed the length and efficiency of sleep,and detected the level of serum hypoxia inducible factor-1α,erythropoietin(EPO)and clinical intervention before and after intervention.EPO levels,and investigated satisfaction with the clinical intervention.RESULTS The rate of excellent health knowledge in the intervention group was 93.64%,which was higher than that in the control group(74.23%;P<0.05).Before the intervention,there was no significant difference in Hamilton Anxiety Scale and Pittsburgh Sleep Quality Index scores between the two groups(P>0.05),and after the intervention,the scores of the study group were significantly lower than those of the control group(P<0.05).There was no significant difference in sleep duration and sleep efficiency between the groups before the intervention(P>0.05),and after the intervention,the scores of the study group were significantly larger than those of the control group(P<0.05).There was no significant difference in serum hypoxia inducible factor-1αand EPO between the two groups before intervention(P>0.05),and both research groups were significantly lower than the control group after intervention(P<0.05).According to the questionnaire survey,the intervention satisfaction of the study group was 95.53%,which was higher than that of the control group(80.14%;P<0.05).CONCLUSION The CBT intervention in the treatment of patients with high-altitude-related respiratory diseases helps improve patients'health knowledge,relieve anxiety,improve sleep quality and hypoxia tolerance,and improve nursing satisfaction. 展开更多
关键词 Cognitive behavioral therapy high altitude respiratory disease ANXIETY Sleep quality Hypoxia tolerance
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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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Localized electronic interactions in phosphate cathode:Breaking the V^(4+)/V^(5+)high-voltage barrier for high-energy and long-life sodium-ion batteries
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作者 Jia Kang Siqi Wang +10 位作者 Ling Zhu Duanfeng Xiong Feiyang Teng Xiangsi wu Qiuling Zou Ao Jiang Leyi Zhang Yonggang Huang Renheng Wang Xianming Wu Xianwen Wu 《Journal of Energy Chemistry》 2026年第2期984-994,I0020,共12页
Achieving multi-electron reaction at high operation voltage is the key to increase the energy density of Na_(3)V_(2)(PO_(4))_(3)(NVP)cathode.However,the motivated V^(4+)/V^(5+)redox usually shows inferior reversibilit... Achieving multi-electron reaction at high operation voltage is the key to increase the energy density of Na_(3)V_(2)(PO_(4))_(3)(NVP)cathode.However,the motivated V^(4+)/V^(5+)redox usually shows inferior reversibility and causes serious volume changes.Herein,this article proposes a local electronic interaction mechanism which achieves highly reversible multi-electron reaction of NVP.Particularly,Al-Sn co-doped and carbon coated NVP(Na_(3)Al_(0.1)Sn_(0.1)V_(1.8)(PO_(4))_(3)@C,abbreviated as NASVP@C-2)was prepared by sol-gel method.The doped-Al can activate the redox of V^(4+)/V^(5+)and generate the"pinning effect"to stabilize the crystal structure,and the Sn acts as localized electronic reservoir for charge compensation of V redox.The localized electronic interaction mechanism between Sn and V is revealed by multi ex-situ characterizations.Kinetics tests and density functional theory(DFT)calculations suggest that the Al-Sn co-doping enhances the electronic conductivity and reduces the Na^(+)diffusion barrier in NVP.An extremely low volumetric variation(1.07%)is detected in NASVP@C-2 during cycling.As a result,the highly reversible multielectron(2.53)reaction is achieved in NASVP@C-2,which releases a high capacity of 147.6 mAh g^(-1) at1 C and exhibits exceptional cycle stability and rate capability.This work provides a new strategy to design high energy density and durable NASICON cathode. 展开更多
关键词 Sodium-ion batteries NASICON cathodes Charge compensation Multi-electron reactions high energy density
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