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Pursuing ultrahigh strength-ductility CoCrNi-based medium-entropy alloy by low-temperature pre-aging 被引量:2
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作者 A.X.Li K.W.Kang +5 位作者 J.S.Zhang M.K.Xu D.Huang S.K.Liu Y.T.Jiang G.Li 《Journal of Materials Science & Technology》 2025年第17期115-128,共14页
Developing high-performance alloys with gigapascal strength and excellent ductility is crucial for modern engineering applications.The concept of multi-component high/medium entropy alloys(H/MEAs)provides an innovativ... Developing high-performance alloys with gigapascal strength and excellent ductility is crucial for modern engineering applications.The concept of multi-component high/medium entropy alloys(H/MEAs)provides an innovative approach to designing such alloys.In this work,we developed the Co_(1.5)CrNi_(1.5)Al_(0.2)Ti_(0.2)MEA,which exhibits outstanding mechanical properties at room temperature through low-temperature pre-aging followed by annealing treatment.Tensile testing reveals that the MEA possesses an ultrahigh yield strength of 20±0785 MPa,an ultimate tensile strength of 2365±70 MPa,and exceptional ductility of 15.8%±1.7%.The superior tensile properties are attributed to the formation of fully recrystal-lized heterogeneous structures(HGS)composed of ultrafine grain(UFG)and fine grain(FG)regions,along with discontinuous precipitation of coherent nano-size lamellar L1_(2)precipitates.The mechanical incompatibility between the UFG region and the FG regions during deformation induces the accumulation of a large number of geometrically necessary dislocations at the interface,resulting in strain distribution and hetero-deformation-induced(HDI)stress accumulation,contributing significantly to HDI strengthening.HDI strengthening,precipitation strengthening,and grain boundary strengthening are the primary mechanisms responsible for the ultra-high yield strength of the MEA.During deformation,the dominant deformation mechanisms include dislocation slip,deformation-induced stacking faults,and Lomer-Cottrell locks,with minor deformation twinning.The synergistic interaction of these multiple deformation modes provides the MEA with excellent work hardening capability,delaying plastic instability and achieving an excellent combination of strength and ductility.This study provides an effective strategy for synergistically strengthening MEAs by combining HDI strengthening with traditional strengthening mechanisms.These findings pave the way for the development of advanced structural materials with high performance tailored for demanding applications in engineering. 展开更多
关键词 high/medium entropy alloy Recrystallized heterogeneous structure Ultra-high mechanical properties Synergistic strengthening Multiple deformation modes
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Dynamic oxidation synthesis of medium/high-entropy oxide catalysts with ultrahigh coordination disorder:Efficient ammonia borane hydrolysis
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作者 Nuo Lei Panpan Zhou +5 位作者 Junrui Zhang Fei Chu Changjun Cheng Lixin Chen Liuzhang Ouyang Xuezhang Xiao 《Journal of Energy Chemistry》 2025年第11期920-931,I0021,共13页
Ammonia borane(AB)is a promising hydrogen storage medium widely used for hydrogen generation,but its slow hydrolysis kinetics limits its applications.Medium/high-entropy materials(M/HEMs)have emerged as efficient cata... Ammonia borane(AB)is a promising hydrogen storage medium widely used for hydrogen generation,but its slow hydrolysis kinetics limits its applications.Medium/high-entropy materials(M/HEMs)have emerged as efficient catalysts due to their complementary elemental and structural properties.We developed a deposition in-situ reduction(D-ISR)approach for the rapid synthesis of single-phase medium/high-entropy oxides(M/HEOs)at room temperature,along with establishing general criteria for M/HEOs synthesis based on component properties.Deposition facilitates the incorporation of active elements(Ti/Zr/V/Cr/Nb),which significantly enhance the enthalpy-driven force of the dynamic oxidation(DO)process via an“active element coordination”strategy,thereby overcoming low-temperature solid solubility limitations.Nine-component HEOs and large-scale experiments confirm the universality and mass-production potential of the D-ISR approach.CoCuNiTi-O/AC synthesized via this strategy exhibits pronounced crystal distortion and disorder(Co–O coordination number=10.2),enhancing the Co–O coordination environment and mitigating Ostwald ripening.This leads to high activity and significantly enhanced structural stability,achieving a turnover frequency of 236.6 min^(-1)for ammonia borane hydrolysis,15 times higher than Co-O/AC and surpassing the most non-noble catalysts.These observations highlight an efficient M/HEOs synthesis methodology that advances M/HEMs applications in nanoenergy. 展开更多
关键词 medium/high-entropy oxides Dynamic oxidation Room-temperature rapid synthesis Ammonia borane hydrolysis Ostwald ripening
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As-cast Ti_(x)(AlVCr)_(100−x)light-weight medium entropy alloys with high strength and uniform compressive plasticity
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作者 Ming-jie KAI Yu-jie MA +7 位作者 Xiao-tian WANG Liang CHENG Jian-bo HU Yao-yao HU Tai-ran XU Gui-jiang LI Xiang-kang MENG Zhen-hua CAO 《Transactions of Nonferrous Metals Society of China》 2025年第1期194-206,共13页
The effect of Ti content on the microstructure and mechanical properties of as-cast light-weight Ti_(x)(AlVCr)_(100−x)medium entropy alloys was studied by compressive tests,X-ray diffraction,scanning electron microsco... The effect of Ti content on the microstructure and mechanical properties of as-cast light-weight Ti_(x)(AlVCr)_(100−x)medium entropy alloys was studied by compressive tests,X-ray diffraction,scanning electron microscopy and transmission electron microscopy.The results suggest that yield strength increases and then decreases with the increment of Ti content.The Ti_(60)(AlVCr)_(40)alloy has the best combination of high strength of 1204 MPa and uniform plastic strain of 70%,possessing a high specific yield strength of 255 MPa·cm^(3)/g.The enhancement of strength is mainly attributed to the synergic effects of solid-solution and coherent nano-precipitation strengthening,while dislocation motion such as dislocation pinning,entanglement and dislocation cells significantly increases the strain-hardening capacity. 展开更多
关键词 TiAlVCr medium entropy alloy solid solution strengthening b2 precipitate strain hardening behavior
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Low-Temperature Rapid Drying of Viscous Sludge Via Non-Phase Change Based on Particle High-Speed Self-Rotation and Medium Dispersion in Cyclone
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作者 Junjie Liu Qiqi Li +9 位作者 Yanan Liang Jianping Li Yi Liu Qiong Li Tingting Cheng Aosong Wei Shenggui Ma Xia Jiang Hualin Wang Pengbo Fu 《Engineering》 2025年第7期96-105,共10页
Drying operations are of grave importance to realize the reduction and utilization of sewage sludge resources,but the conventional thermal evaporation drying(TED)technology presents challenges due to the need for a la... Drying operations are of grave importance to realize the reduction and utilization of sewage sludge resources,but the conventional thermal evaporation drying(TED)technology presents challenges due to the need for a large amount of thermal energy to conquer the phase-change latent heat of moisture.Herein,we report a non-phase change technology based on particle high-speed self-rotation in a cyclone for fast,low-temperature drying of viscous sludge with high-moisture contents.Dispersed phase medium(DPM)is introduced into the cyclone self-rotation drying(CSRD)reactor to enhance the dispersion of the viscous sludge.The effects of carrier gas temperature,feeding rate,size,and proportion of DPM particles in the drying process are systematically examined.Under optimal operating conditions,the weighted content of moisture in the viscous sludge could be reduced from 80%to 15.01%in less than 5 s,achieving a high drying efficiency of 95.79%.Theoretical calculations also reveal that 89.26%of the moisture is removed through non-phase change pathway,contributing to a 522-fold increase in the drying rate of CSRD compared to TED technology.This investigation presents a sustainable effective approach for high moisture viscous sludge treatment with low energy consumption and carbon emissions. 展开更多
关键词 Sludge drying CYCLONE Particle high-speed self-rotation Viscous sludge Dispersed phase medium(DPM) Non-phase change
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Kinetic and thermodynamic calculations of reaction involving high aluminum low manganese steels and medium SiO_(2)medium Al_(2)O_(3)mold fluxes with different initial aluminum contents
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作者 Rong-zhen Mo Ying Ren Li-feng Zhang 《Journal of Iron and Steel Research International》 2025年第9期2808-2819,共12页
Steel–flux reactions involving the high aluminum(0.75–3.85 wt.%Al)low manganese(2.2 wt.%Mn)steel and the 18 wt.%SiO_(2)–18 wt.%Al2O3 mold flux were investigated.The results indicated that the reaction rate increase... Steel–flux reactions involving the high aluminum(0.75–3.85 wt.%Al)low manganese(2.2 wt.%Mn)steel and the 18 wt.%SiO_(2)–18 wt.%Al2O3 mold flux were investigated.The results indicated that the reaction rate increased when the initial aluminum content increased from 0.76 to 3.85 wt.%.Utilizing the two-film theory,a steel–flux reaction kinetic model controlled by mass transfer was established,which considered the influence of the initial composition on the density of liquid steel and flux.The mass transfer of aluminum in the steel phase was the reaction rate-determining step.It was confirmed that the mass transfer coefficient of Al was 1.87×10^(−4).The predicted results of the kinetic model were consistent and reliable with the experimental results.Thermodynamic equilibrium calculation was performed using FactSage 8.2,which was compared with the steel and flux final composition after 30 min.The content of initial aluminum in the liquid steel played a critical role in the SiO_(2)equilibrium content of the mold flux.In addition,the steel–flux reaction between[Al]and(SiO_(2))occurred with the initial SiO_(2)content in the mold flux lower than 3 wt.%. 展开更多
关键词 high aluminum steel Thermodynamic equilibrium Steel-flux reaction Kinetic model Mold flux
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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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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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A sustainable and high value-added strategy under lignite and waste silicon powder to construct SiC nanowires for electromagnetic wave absorption
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作者 Wenhao Wang Xiaolin Lan +6 位作者 Haoquan Hao Jingxiang Liu Yong Shuai Qinghe Jing Shouqing Yan Jie Guo Zhijiang Wang 《International Journal of Minerals,Metallurgy and Materials》 2026年第1期347-356,共10页
The electromagnetic wave absorption of silicon carbide nanowires is improved by their uniform and diverse cross-structures.This study introduces a sustainable and high value-added method for synthesizing silicon carbi... The electromagnetic wave absorption of silicon carbide nanowires is improved by their uniform and diverse cross-structures.This study introduces a sustainable and high value-added method for synthesizing silicon carbide nanowires using lignite and waste silicon powder as raw materials through carbothermal reduction.The staggered structure of nanowires promotes the creation of interfacial polarization,impedance matching,and multiple loss mechanisms,leading to enhanced electromagnetic absorption performance.The silicon carbide nanowires demonstrate outstanding electromagnetic absorption capabilities with the minimum reflection loss of-48.09 d B at10.08 GHz and an effective absorption bandwidth(the reflection loss less than-10 d B)ranging from 8.54 to 16.68 GHz with a thickness of 2.17 mm.This research presents an innovative approach for utilizing solid waste in an environmentally friendly manner to produce broadband silicon carbide composite absorbers. 展开更多
关键词 LIGNITE waste silicon powder SiC nanowires electromagnetic wave absorption high value-added
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Lifestyle behaviors,serum metabolites and high myopia:Mendelian randomization and mediation analysis
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作者 Nian-En Liu Xiao-Tong Xu Xiao-Bing Yu 《International Journal of Ophthalmology(English edition)》 2026年第1期140-148,共9页
AIM:To explore the causal relationship between several possible behavioral factors and high myopia(HM)using multivariable Mendelian randomization(MVMR)approach and to find the mediators among them with mediation analy... AIM:To explore the causal relationship between several possible behavioral factors and high myopia(HM)using multivariable Mendelian randomization(MVMR)approach and to find the mediators among them with mediation analysis.METHODS:The causal effects of several behavioral factors,including screen time,education time,time spent outdoors,and physical activity,on the risk of HM using univariable Mendelian randomization(MR)and MVMR analyses were first assessed.Genome-wide association study summary statistics of serum metabolites were also used in mediation analysis to determine the extent to which serum metabolites mediate the effects of behavioral factors on HM.RESULTS:MR analyses indicated that both increased time spent outdoors and a higher frequency of moderate physical activity significantly reduced the risk of HM.Further MVMR analysis confirmed that moderate physical activity independently contributed to a lower risk of HM.Additionally,MR analyses identified 13 serum metabolites significantly associated with HM,of which 12 were lipids and one was an amino acid derivative.Mediation analysis revealed that six lipid metabolites mediated the protective effects of moderate physical activity on HM,with the highest mediation proportion observed for 1-(1-enyl-palmitoyl)-GPC(p-16:0;30.83%).CONCLUSION:This study suggests that in addition to outdoor time,moderate physical activity habits may have an independent protective effect against HM and pointed to lipid metabolites as priority targets for the prevention due to low physical activity.These results emphasize the importance of physical activity and metabolic health in HM and underscore the need for further study of these complex associations. 展开更多
关键词 high myopia physical activity serum metabolites multivariable Mendelian randomization mediation analysis
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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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Steering China’s High-Quality Growth
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作者 《China Today》 2026年第1期16-19,共4页
Chinese President Xi Jinping has guided China through a year of resilient growth via forward-looking reforms and innovation-driven transformation that is shaping the nation’s economic trajectory for 2026 and beyond.
关键词 forward looking reforms high quality growth STEERING resilient growth innovation driven transformation
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Nanosized Anatase TiO_(2) with Exposed(001)Facet for High-Capacity Mg^(2+)Ion Storage in Magnesium Ion Batteries
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作者 Rong Li Liuyan Xia +6 位作者 Jili Yue Junhan Wu Xuxi Teng Jun Chen Guangsheng Huang Jingfeng Wang Fusheng Pan 《Nano-Micro Letters》 2026年第1期438-457,共20页
Micro-sized anatase TiO_(2) displays inferior capacity as cathode material for magnesium ion batteries because of the higher diffusion energy barrier of Mg^(2+)in anatase TiO_(2) lattice.Herein,we report that nanosize... Micro-sized anatase TiO_(2) displays inferior capacity as cathode material for magnesium ion batteries because of the higher diffusion energy barrier of Mg^(2+)in anatase TiO_(2) lattice.Herein,we report that nanosized anatase TiO_(2) exposed(001)facet doubles the capacity compared to the micro-sized sample ascribed to the interfacial Mg^(2+)ion storage.First-principles calculations reveal that the diffusion energy barrier of Mg^(2+)on the(001)facet is significantly lower than those in the bulk phase and on(100)facet,and the adsorption energy of Mg^(2+)on the(001)facet is also considerably lower than that on(100)facet,which guarantees superior interfacial Mg^(2+)storage of(001)facet.Moreover,anatase TiO_(2) exposed(001)facet displays a significantly higher capacity of 312.9 mAh g^(−1) in Mg-Li dual-salt electrolyte compared to 234.3 mAh g^(−1) in Li salt electrolyte.The adsorption energies of Mg^(2+)on(001)facet are much lower than the adsorption energies of Li+on(001)facet,implying that the Mg^(2+)ion interfacial storage is more favorable.These results highlight that controlling the crystal facet of the nanocrystals effectively enhances the interfacial storage of multivalent ions.This work offers valuable guidance for the rational design of high-capacity storage systems. 展开更多
关键词 Magnesium ion batteries high capacity Nanosized anatase TiO_(2) Crystal facet Interfacial ion storage
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China’s Economy Builds Momentum for High-Quality Growth
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作者 Zhang Hui 《China Today》 2026年第1期2-2,共1页
As the global economy navigates through a complex landscape of uncertainty and shifting dynamics,the Chinese economy stands out for its remarkable resilience,inherent vitality,and steadfast commitment to a transformat... As the global economy navigates through a complex landscape of uncertainty and shifting dynamics,the Chinese economy stands out for its remarkable resilience,inherent vitality,and steadfast commitment to a transformative,high-quality development path.The latest economic indicators,strategic policy guidance from the Central Economic Work Conference,and a surge in international confidence collectively present a picture of an economy not merely recovering,but actively building its new growth engines.China is transitioning towards a more sustainable and innovation-driven model,with new quality productive forces playing an increasingly prominent role. 展开更多
关键词 economic resilience sustainable growth innovation driven model international confidence economic indicatorsstrategic policy guidance high quality development
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Formability and strengthening mechanism of AA6061 tubular components under solid granule medium internal high pressure forming 被引量:6
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作者 毕江 赵长财 +2 位作者 杜冰 国庆波 董国疆 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2018年第2期226-234,共9页
A new technological process of tube forming was developed, namely solution treatment → granule medium internal high pressure forming → artificial aging. During this process, the mechanical properties of AA6061 tube ... A new technological process of tube forming was developed, namely solution treatment → granule medium internal high pressure forming → artificial aging. During this process, the mechanical properties of AA6061 tube can be adjusted by heat treatment to satisfy the process requirements and the processing method can also be realized by granule medium internal high pressure forming technology with the features of convenient implementation, low requirement to equipment and flexible design in product. Results show that, at a solution temperature of 560 ℃ and time of 120 min, the elongation of AA6061 increases by 313%, but the strength and the hardness dramatically decrease. At an aging temperature of 180 ℃ and time of 360 min, the strength and hardness of AA6061 alloy are recovered to the values of the as-received alloy. The maximum expansion ratio(MER) of AA6061 tube increases by 25.5% and the material properties of formed tube reach the performances of raw material. 展开更多
关键词 AA6061 alloy internal high pressure forming heat treatment strengthening mechanism
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INTERFERENTIAL MODULATION-RESOLVED IMAGING OF AN ABSORBING OBJECT HIDDEN IN HIGHLY SCATTERING MEDIUM
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作者 刘迎 张西芹 +1 位作者 桑梅 马世宁 《Transactions of Tianjin University》 EI CAS 1999年第1期65-67,共3页
In this paper an absorbing object hidden in a highly scattering medium is shown to be visibleunder the illumination of a cw coherent light by using interferometry,and a new filtering algorithm thethreshold density fil... In this paper an absorbing object hidden in a highly scattering medium is shown to be visibleunder the illumination of a cw coherent light by using interferometry,and a new filtering algorithm thethreshold density filter is used to extract interference pattern from the speckle noise background fast andefficiently. The submillimeter spatial resolution is achieved. 展开更多
关键词 high scattering inteferential imaging modulatlon-resolved
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Characteristic dislocation slip behavior in polycrystalline HfNbTiZr refractory medium entropy alloy
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作者 Qian He Shuhei Yoshida +2 位作者 Shinji Okajo Masaki Tanaka Nobuhiro Tsuji 《Journal of Materials Science & Technology》 2025年第7期29-39,共11页
The present work reports characteristics of dislocation slip behavior in an equi-atomic HfNbTiZr refractory medium entropy alloy(RMEA)and its systematic comparison with pure niobium(Nb).Fully-recrystallized specimens ... The present work reports characteristics of dislocation slip behavior in an equi-atomic HfNbTiZr refractory medium entropy alloy(RMEA)and its systematic comparison with pure niobium(Nb).Fully-recrystallized specimens were fabricated by cold rolling and subsequent annealing,and uniaxial tensile deformation was applied at room temperature.Slip trace morphologies on the surfaces of the tensile-deformed ma-terials were quantitatively characterized,and the so-calledψand x relationships of the observed slip traces were evaluated by a newly developed method for polycrystalline specimens.Wavy slip traces were observed in most grains in the pure Nb.They consisted of low-indexed slip planes,such as{110},and{112},and high-indexed(or undetermined)slip planes.Some straight slip traces persisting on the low-indexed slip planes were also found in the pure Nb.In contrast,straight slip traces were dominant in the RMEA.The straight slip traces in the RMEA were not parallel to particular slip planes but mostly distributed along the maximum shear stress plane(MSSP),indicating that frequent cross slip in very short intervals occurred.Large deviations of slip planes from the MSSP in a few grains of the RMEA were attributed to the slip transfer from neighboring grains as a characteristic of polycrystalline materi-als.Frequent cross slip in short intervals,attributed to homogeneous slip resistance distribution for screw dislocations in the RMEA originating from the chemical heterogeneity on an atomic scale,was proposed as a novel mechanism responsible for the unique slip behavior and macroscopic deformation behavior. 展开更多
关键词 Dislocation slip Cross slip Slip trace Polycrystalline materials Refractory high/medium entropy alloys
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Heat treatment and granule medium internal highpressure forming of AA6061 tube 被引量:3
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作者 BI Jiang ZHAO Chang-cai +3 位作者 BI Meng-meng DU Bing CHEN Xiao-hua DONG Guo-jiang 《Journal of Central South University》 SCIE EI CAS CSCD 2017年第5期1040-1049,共10页
The new forming process of AA6061 alloy tube, including solution treatment, granule medium internal high-pressure forming and aging treatment, was developed. The AA6061 alloy tube via heat treatment satisfied the form... The new forming process of AA6061 alloy tube, including solution treatment, granule medium internal high-pressure forming and aging treatment, was developed. The AA6061 alloy tube via heat treatment satisfied the forming requirement, and the granule medium internal high pressure forming method for AA6061 alloy tube was also realized by using convenient implementation with low requirement of equipment and flexible design of product. At a solution temperature of 560℃ and time of 120 min, the elongation of the AA6061 extruded tube increases by 300% and the strength and the hardness dramatically decrease too. Therefore, the AA6061 alloy tube meets the requirement of internal high-pressure forming because of the improvement of formability. The experiments shows that the strength and hardness of AA6061 alloy workpiece recover to that of the as-received alloy at an aging temperature of 180℃ and time of 360 min, and the strength of AA6061 alloy workpiece is equal to the base alloy. The typical parts of convex ring tube, stepped shaft tube and hexagonal tube were successfully produced in lab by using the present forming method. The forming tests show that the maximum expansion ratio(MER) of the AA6061 extruded tube increases by 25.5% and the material properties of formed AA6061 alloy tube reached the performance of as-received alloy. 展开更多
关键词 aluminum alloy TUBE solution TREATMENT aging TREATMENT GRANULE medium INTERNAL high pressure FORMING
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Triple Medium Physical Model of Post Fracturing High-Rank Coal Reservoir in Southern Qinshui Basin 被引量:4
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作者 Shiqi Liu Shuxun Sang +4 位作者 Qipeng Zhu Jiefang Zhang Hefeng Gao Huihu Liu Lixing Lin 《Journal of Earth Science》 SCIE CAS CSCD 2015年第3期407-415,共9页
In this paper, influences on the reservoir permeability, the reservoir architecture and the fluid flow pattern caused by hydraulic fracturing are analyzed. Based on the structure and production fluid flow model of pos... In this paper, influences on the reservoir permeability, the reservoir architecture and the fluid flow pattern caused by hydraulic fracturing are analyzed. Based on the structure and production fluid flow model of post fracturing high-rank coal reservoir, Warren-Root Model is improved. A new physical model that is more suitable for post fracturing high-rank coal reservoir is established. The results show that the width, the flow conductivity and the permeability of hydraulic fractures are much larger than natural fractures in coal bed reservoir. Hydraulic fracture changes the flow pattern of gas and flow channel to wellbore, thus should be treated as an independent medium. Warrant-Root Model has some limitations and can’t give a comprehensive interpretation of seepage mechanism in post fracturing high-rank coal reservoir. Modified Warrant-Root Model simplifies coal bed reservoir to an ideal system with hydraulic fracture, orthogonal macroscopic fracture and cuboid matrix. Hydraulic fracture is double wing, vertical and symmetric to wellbore. Coal bed reservoir is divided into cuboids by hydraulic fracture and further by macroscopic fractures. Flow behaviors in coal bed reservoir are simplified to three step flows of gas and two step flows of water. The swap mode of methane between coal matrix and macroscopic fractures is pseudo steady fluid channeling. The flow behaviors of methane to wellbore no longer follow Darcy’s Law and are mainly affected by inertia force. The flow pattern of water follows Darcy’s Law. The new physical model is more suitable for post fracturing high-rank coal reservoir. 展开更多
关键词 triple medium physical model high-rank coal reservoir hydraulic fracture SEEPAGE southern Qinshui Basin
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Effects of Combined Instantaneous High-Pressure and MediumTemperature on the Retention of Total Vitamin Cin Wax Gourd Juices 被引量:2
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作者 LIUJin-jie WANGWu +2 位作者 ZHANGLi HEJing-min CHENCong-gui 《Agricultural Sciences in China》 CAS CSCD 2003年第8期919-923,共5页
Based on the instantaneous high-pressure(IHP)produced by high-pressure single pole-cylinder pump, the effects of combining this pressure with medium temperature on the retention of total vitamin C(Vc)in wax gourd juic... Based on the instantaneous high-pressure(IHP)produced by high-pressure single pole-cylinder pump, the effects of combining this pressure with medium temperature on the retention of total vitamin C(Vc)in wax gourd juices were investigated under 20 - 80 MPa, 35 - 58℃, pH 3. 0 - 6. 0 and processing time 0-8 min. Results showed that the loss of Vc increased with elevated processing temperatures(50 MPa, 4 min). When the temperature of raw juices was 35℃, the retention of total Vc was higher under 40 - 60 MPa than that under the pressure < 40 MPa or > 60 MPa, and it was up to 94%(4 min). The retention of total Vc decreases slowly within 6 min, but rapidly after 6 min. The pH can also influence the retention of total Vc, and this retention can come to a highest point at pH 6.0. 展开更多
关键词 Instantaneous high-pressure medium temperature Combined process Vitamin C RETENTION
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