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Research Status of High-Entropy Alloys Based on Artificial Intelligence Technology
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作者 YU Zhiqi ZHAO Yanchun +5 位作者 XUE Baorui DANG Wenxia MA Huwen SU Yu LAN Yunbo feng li 《有色金属(中英文)》 北大核心 2025年第5期735-747,共13页
High-Entropy Alloys(HEAs)exhibit significant potential across multiple domains due to their unique properties.However,conventional research methodologies face limitations in composition design,property prediction,and ... High-Entropy Alloys(HEAs)exhibit significant potential across multiple domains due to their unique properties.However,conventional research methodologies face limitations in composition design,property prediction,and process optimization,characterized by low efficiency and high costs.The integration of Artificial Intelligence(AI)technologies has provided innovative solutions for HEAs research.This review presented a detailed overview of recent advancements in AI applications for structural modeling and mechanical property prediction of HEAs.Furthermore,it discussed the advantages of big data analytics in facilitating alloy composition design and screening,quality control,and defect prediction,as well as the construction and sharing of specialized material databases.The paper also addressed the existing challenges in current AI-driven HEAs research,including issues related to data quality,model interpretability,and cross-domain knowledge integration.Additionally,it proposed prospects for the synergistic development of AI-enhanced computational materials science and experimental validation systems. 展开更多
关键词 high-entropy alloys artificial intelligence structural modeling mechanical property big data
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Structure-activity relationship on tensile properties under DRX and slip system activity of U-CVCDEed AZ31 magnesium alloy
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作者 Qiang liu feng li +2 位作者 Fu Wei Kang Hai Bo Wang Shun Luo 《Journal of Magnesium and Alloys》 2025年第8期3906-3917,共12页
Given the limitations of traditional hot extrusion methods in improving the microstructure and mechanical properties of magnesium(Mg)alloys,this paper attempts to treat AZ31 Mg alloy billet by pre-upsetting continuous... Given the limitations of traditional hot extrusion methods in improving the microstructure and mechanical properties of magnesium(Mg)alloys,this paper attempts to treat AZ31 Mg alloy billet by pre-upsetting continuous variable cross-section direct extrusion(U-CVCDE).The effects of dynamic recrystallization behavior and slip system activity on texture evolution and mechanical properties of CVCDE Mg alloys with different pre-upsetting amounts were systematically analyzed.The results indicate that the introduction of the pre-upsetting process promotes dynamic recrystallization during the CVCDE process.The recrystallization proportion shows a trend of first rising and then decreasing with the increase of the pre-upsetting amount.Among them,the proportion of recrystallization grains in the U2-CVCDE-formed structural parts is as high as 88.3%.The average grain sizes of U1-CVCDE,U2-CVCDE,and U3-CVCDE were 6.01μm,4.90μm,and10.45μm,respectively.In addition,following U-CVCDE,the pyramidal slip of each forming component consistently maintains a high level of activation and opening and dominates,making more grains deflect in the axial extrusion direction of C to varying degrees,which is conducive to the uniform distribution of stress in more grains during plastic deformation.The synergistic effect of dynamic recrystallization behavior and the high activity of the pyramidal slip system significantly weakened the(0001)basal texture strength,and the maximum basal texture strength showed a gradually decreasing trend,among which the base surface texture strength of U3-CVCDE formed parts was only 9.9.The U-CVCDE process is employed to achieve deep modification of Mg alloy,and excellent comprehensive mechanical properties are obtained;among them,the yield and tensile strength of U2-CVCDE are as high as 243.4 MPa and 317.5 MPa,respectively,and the elongation after breaking is up to 21.3%.This study introduces a practical new idea for investigating the extrusion forming technology of high-performance Mg alloys. 展开更多
关键词 Pre-upsetting treatment CVCDE RECRYSTALLIZATION Slip system TEXTURE Mechanical property
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Present Situation Analysis and High-quality Development Countermeasures of Wadi Sheep Industry in Lubei Region
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作者 Shijin GUO Bing ZHANG +13 位作者 ling MO Xiaoliang WANG Jianjun WANG Lu GUO Jian ZHAO Xin li Weiqin MENG Pengfei MAO Shuguang li Shiyun TANG Shijun FU feng li Wenjian MA Jinliang WANG 《Agricultural Biotechnology》 2025年第1期13-18,共6页
This paper systematically analyzed the development status of sheep industry in Lubei region,and comprehensively expounded the scale and distribution of key industries,breed resources and genetic characteristics,feedin... This paper systematically analyzed the development status of sheep industry in Lubei region,and comprehensively expounded the scale and distribution of key industries,breed resources and genetic characteristics,feeding management status,disease prevention and control and veterinary services,and sheep product processing and sales.The research shows that the sheep industry in Lubei region has formed a certain scale,but there are some problems such as intensified resource and environmental constraints,unreasonable industrial structure,insufficient scientific and technological innovation capacity and market competitiveness to be improved.In view of these problems,this paper put forward some countermeasures and suggestions to promote the high-quality development of the industry,including establishing forage and feed system,promoting the adjustment and optimization of industrial structure,strengthening scientific and technological innovation and talent cultivation and introduction,and enhancing brand influence and market competitiveness,providing useful reference for the sustainable development of sheep industry in Lubei region. 展开更多
关键词 Wadi Sheep Industrial status quo High quality Development countermeasures PROSPECT
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Integrative transcriptomic and proteomic analysis reveals that SERPING1 inhibits neuronal proliferation via the CaMKII-CREB-BDNF pathway in schizophrenia
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作者 feng li Xing Ren +3 位作者 Jia-Xiu liu Tian-Dao Wang Bi Wang Xiao-Bin Wei 《World Journal of Psychiatry》 2025年第2期193-208,共16页
BACKGROUND Schizophrenia(SZ),a chronic and widespread brain disorder,presents with complex etiology and pathogenesis that remain inadequately understood.Despite the absence of a universally recognized endophenotype,pe... BACKGROUND Schizophrenia(SZ),a chronic and widespread brain disorder,presents with complex etiology and pathogenesis that remain inadequately understood.Despite the absence of a universally recognized endophenotype,peripheral blood mononuclear cells(PBMCs)serve as a robust model for investigating intracellular alterations linked to SZ.AIM To preliminarily investigate potential pathogenic mechanisms and identify novel biomarkers for SZ.METHODS PBMCs from SZ patients were subjected to integrative transcriptomic and proteomic analyses to uncover differentially expressed genes(DEGs)and differentially expressed proteins while mapping putative disease-associated signaling pathways.Key findings were validated using western blot(WB)and real-time fluorescence quantitative PCR(RT-qPCR).RNAi-lentivirus was employed to transfect rat hippocampal CA1 neurons in vitro,with subsequent verification of target gene expression via RT-qPCR.The levels of neuronal conduction proteins,including calmodulin-dependent protein kinase II(caMKII),CREB,and BDNF,were assessed through WB.Apoptosis was quantified by flow cytometry,while cell proliferation and viability were evaluated using the Cell Counting Kit-8 assay.RESULTS The integration of transcriptomic and proteomic analyses identified 6079 co-expressed genes,among which 25 DEGs were significantly altered between the SZ group and healthy controls.Notably,haptoglobin(HP),lactotransferrin(LTF),and SERPING1 exhibited marked upregulation.KEGG pathway enrichment analysis implicated neuroactive ligand-receptor interaction pathways in disease pathogenesis.Clinical sample validation demonstrated elevated protein and mRNA levels of HP,LTF,and SERPING1 in the SZ group compared to controls.WB analysis of all clinical samples further corroborated the significant upregulation of SERPING1.In hippocampal CA1 neurons transfected with lentivirus,reduced SERPING1 expression was accompanied by increased levels of CaMKII,CREB,and BDNF,enhanced cell viability,and reduced apoptosis.CONCLUSION SERPING1 may suppress neural cell proliferation in SZ patients via modulation of the CaMKII-CREB-BDNF signaling pathway. 展开更多
关键词 TRANSCRIPTOMICS Proteomics SCHIZOPHRENIA SERPING1 Pathogenesis
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Crystal growth kinetics of single-crystal Ni-rich layered cathodes for high-energy lithium-ion batteries
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作者 feng li Yu-hang TIAN +5 位作者 Lu-xia GE Sheng-long FAN Mao-sheng GONG Ke FAN Pei-yu HOU Xian-qi WEI 《Transactions of Nonferrous Metals Society of China》 2025年第6期1975-1986,共12页
The effects of synthesis conditions,especially the heating rate,on the reaction kinetics of Ni-rich cathodes were systematically studied.The growth rate of Ni-rich oxide increases continuously as the heating rate incr... The effects of synthesis conditions,especially the heating rate,on the reaction kinetics of Ni-rich cathodes were systematically studied.The growth rate of Ni-rich oxide increases continuously as the heating rate increases.Ab initio molecular dynamics simulations demonstrate that a high heating rate induces anabatic oscillations,indicating a decrease in thermodynamic stability and a tendency for the crystal surface to undergo reconstruction.The presence of an intermediate phase at the grain boundary amplifies atomic migration-induced interface fusion and consequently augments crystal growth kinetics.However,the excessively high heating rate aggravates the Li+/Ni2+mixing in the Ni-rich cathode.The single-crystal Ni-rich cathode exhibits enhanced structural/thermal stability but a decreased specific capacity and rate performance compared with its polycrystalline counterpart. 展开更多
关键词 lithium-ion battery Ni-rich cathode single crystal growth kinetics heating rate
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Unusual tensile strengths and strain-hardening behaviors and their structural correlation of Mg-RE solid solution
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作者 Wenbo Luo Rongsheng Bai +7 位作者 Zhilei Yu Xiuzhu Han Tong Guo Zhiyong Xue Chen Wen Mingyue Zheng feng li Zhihao lin 《Journal of Magnesium and Alloys》 2025年第8期4032-4044,共13页
This study systematically investigates the unusual tensile mechanical behavior of Mg-RE solid solution(SS)alloys,exhibiting anomalous tensile strengths(ATS)and an enhanced strain-hardening rate at high temperature.Bot... This study systematically investigates the unusual tensile mechanical behavior of Mg-RE solid solution(SS)alloys,exhibiting anomalous tensile strengths(ATS)and an enhanced strain-hardening rate at high temperature.Both the peak ultimate tensile strength(UTS)and tensile yield strength(TYS)values occur at 150-200℃,which are 12-50%higher compared to those at room temperature(RT).Meanwhile,the strain-hardening rate increases with the temperature rising from RT to 200℃ during the plastic deformation process.The results reveal that the formation of stacking faults(SFs)and the locking of dislocations,particularly immobile (c) partial dislocations,enhance resistance to plastic deformation,leading to higher strengths at high temperature.Furthermore,the interactivity between SFs and (c+a) dislocations intensify with rising of temperature.The presence of RE atoms in the SS plays a critical role in this unique mechanical behavior,as they preferentially occupy non-basal planes rather than basal planes,thereby reducing the stacking fault(SF)formation energy.This study provides new insights into the high-temperature strengthening mechanisms of Mg-RE based alloys,offering potential guidance for the design of advanced lightweight materials with superior mechanical properties. 展开更多
关键词 Anomalous tensile strength Mg-RE alloy Solid solution HEAT-RESISTANCE Molecular dynamics
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Engineering the diphasic Li-rich Mn-based composite with alleviated Jahn-Teller effect for high-energy Li-ion batteries
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作者 feng li Jia-Cheng li +4 位作者 Mao-Sheng Gong Ze-Zhou lin Xuan-Ming Chang Mo-Han Dong Pei-Yu Hou 《Rare Metals》 2025年第5期2945-2957,共13页
The unique oxygen stacking sequence of O2-type structures restricts the irreversible transition metal movement into Li vacancies for the delithiated Li-rich layered oxides(LLOs)and maintains outstanding voltage stabil... The unique oxygen stacking sequence of O2-type structures restricts the irreversible transition metal movement into Li vacancies for the delithiated Li-rich layered oxides(LLOs)and maintains outstanding voltage stability.However,the ion-exchange synthesis promotes the Mn-ion valence reduction and aggravates the Jahn-Teller(J-T)distortion alongside disproportionation.Since the main oxidation state of the Mn ions is+4 in the traditional O3-type LLOs,synergistic effects of the O2-type and O3-type structures are expected in the O2/O3 diphasic Li-rich material.Herein,O2/O3 biphasic intergrowth LLOs were rationally designed,and the synergic optimization of the biphasic structure was planned to retard the J-T effect.The O2/O3 intergrowth nature was confirmed,and the percentages of the O2 and O3 phases were 56%and 44%,respectively.Density functional theory calculations demonstrated that the Mn^(2+)(EC)sheath had a remarkably lower energy barrier than the Li^(+)(EC)sheath.This finding suggests that Mn^(2+)ions that are dissolved into the electrolyte accelerate the electrolyte oxidization,so the deposition of the cathode electrolyte interface for pristine O2-LLOs causes a high electrochemical impedance.The designed O2/O3 biphasic LLOs boost the capacity stability and suppress the voltage drop upon repeated Li^(+)de-intercalation.The phase regulation strategy offers great potential for developing low-cost LLOs with enhanced structural stability for advanced Li-ion batteries. 展开更多
关键词 Li-ion battery Li-rich cathode Biphasic composite Jahn-Teller effect Structural stability
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Dual-ligand engineering over Au-based catalyst for efficient acetylene hydrochlorination
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作者 Yongsheng Xu lisha Yao +7 位作者 Jian li Yanzhao Dong Dongyang Xie Miaomiao Zhang feng li Yunsheng Dai Jinli Zhang Haiyang Zhang 《Chinese Chemical Letters》 2025年第3期422-426,共5页
Introducing ligand into the surface of gold(Au)-based catalyst has been recognized as an efficient strategy to enhance the performance of catalyst in acetylene hydrochlorination reaction.However,due to the multifactor... Introducing ligand into the surface of gold(Au)-based catalyst has been recognized as an efficient strategy to enhance the performance of catalyst in acetylene hydrochlorination reaction.However,due to the multifactorial deactivation,the usage of single type of ligand has limitations on the performance improvement.In this work,two types of ligands including a molecular 2-methylimidazole and an ionic cetrimonium are selected to protect Au^(n+)species.After kinetics analysis,advanced characterization,and density functional theory simulation,we demonstrate the optimal interaction model between two ligands and Au species:Two 2-methylimidazole molecules are coordinated with high-valent Au species while cetrimonium is interacted via electrostatic interaction.Except the synergistic effect in the decrease of Au species reduction and agglomeration,the existence of molecular ligand greatly increases the adsorption of hydrogen chloride while the ionic ligand significantly inhibits the deposition of coke.Due to the positive effect of dual-ligands,we achieved 97.1%of acetylene conversion and 0.29 h^(−1) of deactivation rate under high gas hourly space velocity of acetylene.This work establishes a foundation to explore the property-activity relationships in Au-based catalyst via ligand engineering. 展开更多
关键词 Acetylene hydrochlorination Gold-based catalyst Dual-ligand engineering Catalytic performance enhancement
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Review of China's policy and management system for the paid use of sea area Feng 被引量:1
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作者 feng li Zenglei Xi Xiangbo liang 《Chinese Journal of Population,Resources and Environment》 2019年第1期58-66,共9页
As a carrier to develop various marine resources, sea area is regulated as a kind of important resources through legislation by many coastal countries with a management system for the paid use of sea area. Since the e... As a carrier to develop various marine resources, sea area is regulated as a kind of important resources through legislation by many coastal countries with a management system for the paid use of sea area. Since the early 1990s, China has begun to implement the paid use and formed an institutional system comprised of three levels after developing it for more than two decades. From 2002 to 2015, the Chinese Government transferred the use right of sea area of 33,910 km2 by paid use and levied a total of 75.89 billion CNY (11.328 billion US dollars) of sea area use payment. Apart from this, the Government has gained rich experience in operating and managing the compensable use of sea area. After retrospectively analyzing the development history of paid use of China’s sea area, the research presents an institutional structure and the implementation of the management system for the paid use of sea area and the main problems therein. On this basis, management policies and feasible policy suggestions are proposed. Research results from this study can provide available references for other developing countries and emerging economies to apply and improve native management system for the paid use of sea area. 展开更多
关键词 PAID USE SEA area POLICY management system China
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大黄素调节TLR4/MyD88/NF-κB信号通路对慢性肾功能衰竭大鼠肠道菌群结构的影响 被引量:2
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作者 胡溪 冯立 +6 位作者 高智 冯雪 彭斌 朱双益 熊玮 王建华 翟晓玲 《中国医院药学杂志》 北大核心 2025年第17期1959-1964,1993,共7页
目的:探究大黄素调节TLR4/MyD88/NF-κB信号通路对慢性肾功能衰竭(chronic renal failure,CRF)大鼠肠道菌群结构的影响。方法:用腺嘌呤灌胃构建CRF大鼠模型,将造模成功的大鼠分为模型组、大黄素低剂量组、大黄素高剂量组、大黄素高剂量+... 目的:探究大黄素调节TLR4/MyD88/NF-κB信号通路对慢性肾功能衰竭(chronic renal failure,CRF)大鼠肠道菌群结构的影响。方法:用腺嘌呤灌胃构建CRF大鼠模型,将造模成功的大鼠分为模型组、大黄素低剂量组、大黄素高剂量组、大黄素高剂量+LPS(TLR4激活剂)组,另设对照组。检测血清中尿素氮(BUN)、肌酐(Scr)、精氨酸加压素(AVP)含量、Scr清除率;ELISA检测血清TNF-α、IL-6和IL-1β水平;HE染色观察大鼠肾脏病理变化;鉴别培养基检测大鼠肠道菌群变化;RTqPCR检测肾脏组织TLR4 mRNA、MyD88 mRNA、NF-κB mRNA的表达;Western blot检测大鼠肾脏组织Bax、Bcl-2、TLR4、MyD88、p-NF-κB/NF-κB蛋白表达。结果:对照组大鼠肾组织结构正常;与对照组相比,模型组大鼠肾小球萎缩硬化,肾组织细胞排列紊乱,肾间质显著增宽并伴有大量炎症细胞浸润,上皮细胞变性坏死,大鼠血清BUN、Scr、AVP水平,TNF-α、IL-6和IL-1β水平,肠球菌、肠杆菌水平,肾脏组织TLR4 mRNA、MyD88 mRNA、NF-κB mRNA表达水平,Bax、TLR4、MyD88、pNF-κB/NF-κB蛋白表达水平升高,Scr清除率、双歧杆菌、乳酸杆菌、Bcl-2蛋白表达水平降低(P<0.05);大黄素低、高剂量组相比于模型组,大鼠肾组织结构形态显著改善,血清BUN、Scr、AVP水平,TNF-α、IL-6和IL-1β水平,肠球菌、肠杆菌水平,肾脏组织TLR4 mRNA、MyD88 mRNA、NF-κB mRNA表达水平,Bax、TLR4、MyD88、p-NF-κB/NF-κB蛋白表达水平降低,Scr清除率、双歧杆菌、乳酸杆菌和Bcl-2蛋白表达水平升高(P<0.05);LPS可减轻大黄素对CRF大鼠的改善作用(P<0.05)。结论:大黄素可促进CRF大鼠肠道有益菌群增长,抑制有害菌,降低炎症和减轻肾脏损伤,可能是通过抑制TLR4/MyD88/NF-κB信号通路实现的。 展开更多
关键词 大黄素 TLR4/MyD88/NF-κB信号通路 慢性肾功能衰竭 肠道菌群
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Regeneration of photovoltaic industry silicon waste toward high-performance lithium-ion battery anode 被引量:3
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作者 Kai Wang Xiao-Bin Zhong +12 位作者 Yue-Xian Song Yao-Hui Zhang Yan-Gang Zhang Xiao-Gang You Pu-Guang Ji Kurbanov Mirtemir Shodievich Umedjon Khalilov Gong-Kai Wang Xin Zhang Xing-liang Yao feng li Jun-Fei liang Hua Wang 《Rare Metals》 SCIE EI CAS CSCD 2024年第10期4948-4960,共13页
The diamond-wire sawing silicon waste(DWSSW)from the photovoltaic industry has been widely considered as a low-cost raw material for lithium-ion battery silicon-based electrode,but the effect mechanism of impurities p... The diamond-wire sawing silicon waste(DWSSW)from the photovoltaic industry has been widely considered as a low-cost raw material for lithium-ion battery silicon-based electrode,but the effect mechanism of impurities presents in DWSSW on lithium storage performance is still not well understood;meanwhile,it is urgent to develop a strategy for changing DWSSW particles into high-performance electrode materials.In this work,the occurrence state of impurities presents in DWSSW was carefully analyzed using in situ Ar ion etching technology Then,the novel Si@C@SiO_(x)@PAl-NDC composite was designed through in situ encapsulation strategy.The obtained Si@C@SiO_(x)@PAl-NDC electrode shows a high first capacity of 2343.4 mAh·g^(-1)with an initial Coulombic efficiency(ICE)of 84.4%under current density of 1.0 A·g^(-1),and can deliver an impressive capacity of 984.9 mAh·g^(-1)after 200 cycles.Combined numerical simulation modeling calculations,the increase in proportion of Si^(4+)/Si^(0)and Si^(3+)/Si^(0)valence states in SiO_(x)layer leads to a decrease in von Mises stress,which ultimately improves the cycling structural stability.Meanwhile,the porous 2D-3D aluminum/nitrogen(Al/N)co-doped carbon layer and nanowires on SiO_(x)layer can provide abundant active sites for lithium storage due to its developed hierarchical pores structure,which facilitates ion transport What is more,the performance of Si@C@SiO_(x)@PAl-NDC//LiFePO_(4)full cell shows its great potential in practical application. 展开更多
关键词 Sawing silicon waste In situ encapsulation Aluminum/nitrogen co-doped Porous carbon nanowires Lithium-ion batteries
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Regulating interfacial chemistry and kinetic behaviors of F/Mo co-doping Ni-rich layered oxide cathode for long-cycling lithium-ion batteries over-20°C-60°C 被引量:1
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作者 Siqi Guan lin Tao +9 位作者 Pei Tang Ruopian Fang Huize Wu Nan Piao Huicong Yang Guangjian Hu Xin Geng lixiang li Baigang An feng li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第7期449-457,共9页
Ni-rich layered oxide cathodes have shown promise for high-energy lithium-ion batteries(LIBs)but are usually limited to mild environments because of their rapid performance degradation under extreme temperature condit... Ni-rich layered oxide cathodes have shown promise for high-energy lithium-ion batteries(LIBs)but are usually limited to mild environments because of their rapid performance degradation under extreme temperature conditions(below0°C and above 50 °C).Here,we report the design of F/Mo co-doped LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(FMNCM)cathode for high-performance LIBs from-20 to 60°C.F^(-) doping with high electronegativity into the cathode surface is found to enhance the stability of surface lattice structure and protect the interface from side reactions with the electrolyte by generating a LiF-rich surface layer.Concurrently,the Mo^(6+) doping suppresses phase transition,which blocks Li^(+)/Ni^(2+) mixing,and stabilizes lithium-ion diffusion pathway.Remarkably,the FMNCM cathode demonstrates excellent cycling stability at a high cutoff voltage of 4.4 V,even at 60°C,maintaining 90.6%capacity retention at 3 C after 150 cycles.Additionally,at temperatures as low as-20°C,it retains 77.1%of its room temperature capacity,achieving an impressive 97.5%capacity retention after 500 cycles.Such stable operation under wide temperatures has been further validated in practical Ah-level pouch-cells.This study sheds light on both fundamental mechanisms and practical implications for the design of advanced cathode materials for wide-temperature LIBs,presenting a promising path towards high-energy and long-cycling LIBs with temperatureadaptability. 展开更多
关键词 Anion-cation co-doping Wide temperature operation Ni-richlayered cathode Phase transition Surface/interface
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Weak Fault Feature Extraction of the Rotating Machinery Using Flexible Analytic Wavelet Transform and Nonlinear Quantum Permutation Entropy 被引量:1
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作者 lili Bai Wenhui li +3 位作者 He Ren feng li TaoYan lirong Chen 《Computers, Materials & Continua》 SCIE EI 2024年第6期4513-4531,共19页
Addressing the challenges posed by the nonlinear and non-stationary vibrations in rotating machinery,where weak fault characteristic signals hinder accurate fault state representation,we propose a novel feature extrac... Addressing the challenges posed by the nonlinear and non-stationary vibrations in rotating machinery,where weak fault characteristic signals hinder accurate fault state representation,we propose a novel feature extraction method that combines the Flexible Analytic Wavelet Transform(FAWT)with Nonlinear Quantum Permutation Entropy.FAWT,leveraging fractional orders and arbitrary scaling and translation factors,exhibits superior translational invariance and adjustable fundamental oscillatory characteristics.This flexibility enables FAWT to provide well-suited wavelet shapes,effectively matching subtle fault components and avoiding performance degradation associated with fixed frequency partitioning and low-oscillation bases in detecting weak faults.In our approach,gearbox vibration signals undergo FAWT to obtain sub-bands.Quantum theory is then introduced into permutation entropy to propose Nonlinear Quantum Permutation Entropy,a feature that more accurately characterizes the operational state of vibration simulation signals.The nonlinear quantum permutation entropy extracted from sub-bands is utilized to characterize the operating state of rotating machinery.A comprehensive analysis of vibration signals from rolling bearings and gearboxes validates the feasibility of the proposed method.Comparative assessments with parameters derived from traditional permutation entropy,sample entropy,wavelet transform(WT),and empirical mode decomposition(EMD)underscore the superior effectiveness of this approach in fault detection and classification for rotating machinery. 展开更多
关键词 Rotating machinery quantum theory nonlinear quantum permutation entropy Flexible Analytic Wavelet Transform(FAWT) feature extraction
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A Lightweight UAV Visual Obstacle Avoidance Algorithm Based on Improved YOLOv8 被引量:1
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作者 Zongdong Du Xuefeng feng +2 位作者 feng li Qinglong Xian Zhenhong Jia 《Computers, Materials & Continua》 SCIE EI 2024年第11期2607-2627,共21页
The importance of unmanned aerial vehicle(UAV)obstacle avoidance algorithms lies in their ability to ensure flight safety and collision avoidance,thereby protecting people and property.We propose UAD-YOLOv8,a lightwei... The importance of unmanned aerial vehicle(UAV)obstacle avoidance algorithms lies in their ability to ensure flight safety and collision avoidance,thereby protecting people and property.We propose UAD-YOLOv8,a lightweight YOLOv8-based obstacle detection algorithm optimized for UAV obstacle avoidance.The algorithm enhances the detection capability for small and irregular obstacles by removing the P5 feature layer and introducing deformable convolution v2(DCNv2)to optimize the cross stage partial bottleneck with 2 convolutions and fusion(C2f)module.Additionally,it reduces the model’s parameter count and computational load by constructing the unite ghost and depth-wise separable convolution(UGDConv)series of lightweight convolutions and a lightweight detection head.Based on this,we designed a visual obstacle avoidance algorithm that can improve the obstacle avoidance performance of UAVs in different environments.In particular,we propose an adaptive distance detection algorithm based on obstacle attributes to solve the ranging problem for multiple types and irregular obstacles to further enhance the UAV’s obstacle avoidance capability.To verify the effectiveness of the algorithm,the UAV obstacle detection(UAD)dataset was created.The experimental results show that UAD-YOLOv8 improves mAP50 by 3.4%and reduces GFLOPs by 34.5%compared to YOLOv8n while reducing the number of parameters by 77.4%and the model size by 73%.These improvements significantly enhance the UAV’s obstacle avoidance performance in complex environments,demonstrating its wide range of applications. 展开更多
关键词 Unmanned aerial vehicle obstacle detection obstacle avoidance algorithm
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高校专利技术转移时空特征研究——以江苏省国家知识产权试点示范高校为例 被引量:2
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作者 封丽 黄潇霏 +1 位作者 石亮 郭泊池 《中国发明与专利》 2025年第3期55-64,共10页
[目的/意义]旨在分析江苏省国家知识产权试点示范高校专利技术转移的时空特征,挖掘其内在的动态变化规律,阐述高校优势学科群对战略性新兴产业的辐射影响,揭示不同区域内高校专利技术转移的扩散效应以及区域创新体系中的作用。[方法/过... [目的/意义]旨在分析江苏省国家知识产权试点示范高校专利技术转移的时空特征,挖掘其内在的动态变化规律,阐述高校优势学科群对战略性新兴产业的辐射影响,揭示不同区域内高校专利技术转移的扩散效应以及区域创新体系中的作用。[方法/过程]基于2014—2023年江苏省国家知识产权试点示范高校专利转让数据,综合采用社会网络分析、专利计量分析等方法,对国家知识产权试点示范高校专利技术转移的整体情况进行分析。[结果/结论 ]针对技术转移现状,提出了完善专利转移评价激励机制、优化专利管理与运营模式、探索优势学科产业辐射路径、改革技术转移人才培养机制的相关建议,为高校专利技术转移提供借鉴。 展开更多
关键词 国家知识产权试点示范高校 专利技术转移 专利转让 时空特征
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基于“肠-肾轴”理论探究益肾排毒方加三七对肾衰竭血清瘦素、血脂、氧化应激及内皮功能的影响
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作者 胡溪 高智 +2 位作者 冯立 熊玮 冯雪 《中华中医药学刊》 北大核心 2025年第5期243-246,共4页
目的基于“肠-肾轴”理论探究益肾排毒方加三七对肾衰竭血清瘦素、血脂、氧化应激及内皮功能的影响。方法选择肾衰竭患者共计60例作为研究对象。对照组30例予以注射用左卡尼汀联合复方α-酮酸片,试验组30例在对照组基础上联用益肾排毒... 目的基于“肠-肾轴”理论探究益肾排毒方加三七对肾衰竭血清瘦素、血脂、氧化应激及内皮功能的影响。方法选择肾衰竭患者共计60例作为研究对象。对照组30例予以注射用左卡尼汀联合复方α-酮酸片,试验组30例在对照组基础上联用益肾排毒方加三七。对比两组临床疗效、血糖、血脂、瘦素、血管内皮功能、氧化应激指标、炎症指标及安全性。结果与对照组相比,试验组总有效率较高(P<0.05)。治疗后,两组血清空腹血糖(fasting plasma glucose,FPG)、总胆固醇(total Cholesterol,TC)、三酰甘油(triglyceride,TG)、瘦素、可溶性细胞间黏附分子-1(soluble intercellular adhesion molecule-1,sICAM-1)、内皮素-1(endothelin,ET-1)、丙二醛(malondialdehyde,MDA)、C反应蛋白(C-reactive,CRP)、肿瘤坏死因子-α(tumor necrosis factor alpha,TNF-α)、白细胞介素-6(interleukin-6,IL-6)水平均较治疗前降低,超氧化物歧化酶(superoxide dismutase,SOD)水平较治疗前升高(P<0.05),试验组血清FPG、TC、TG、瘦素、血清sICAM-1、ET-1、MDA、CRP、TNF-α、IL-6水平低于对照组(P<0.05),SOD水平高于对照组(P<0.05)。两组药物不良反应发生率比较差异无统计学意义(P>0.05)。结论益肾排毒方加三七应用于肾衰竭能够发挥较好疗效,其治疗效果提升可能与改善内皮、氧化应激功能具有密切相关性。 展开更多
关键词 “肠-肾轴”理论 益肾排毒方 肾衰竭 血清瘦素 氧化应激 内皮功能
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Advances in the Nurse-Led Diabetes Management Model
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作者 feng li Yonghong Jiang +1 位作者 lixia Peng liling Wang 《Open Journal of Nursing》 2025年第1期9-20,共12页
Diabetes mellitus is an important chronic disease that affects the health of the population worldwide, causing a serious impact on patients’ quality of life and increasing the burden on the healthcare system. With th... Diabetes mellitus is an important chronic disease that affects the health of the population worldwide, causing a serious impact on patients’ quality of life and increasing the burden on the healthcare system. With the increasing number of diabetic patients, the traditional healthcare model is under tremendous pressure. In recent years, the nurse-led diabetes management model, as an innovative approach to nursing intervention, has gradually become an important part of comprehensive diabetes management. This article reviews the conceptual model, specific types of nurse-led diabetes management models, barriers faced by nurses during implementation, and corresponding strategies, with a view to providing a reference for the management of diabetic patients and the development of diabetes specialty nurses. 展开更多
关键词 Diabetes Mellitus Management Model NURSE-LED Specialized Care
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变径圆管内离散气泡运动行为及变形特性
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作者 李枫 明亮 +3 位作者 邢雷 蒋明虎 赵立新 关帅 《过程工程学报》 北大核心 2025年第4期341-353,共13页
离散气泡在变径圆管内的变形动力学行为是指导气液两相介质输运及分离的重要理论。针对变径圆管结构,开展不同雷诺数及气泡粒径条件下的变径场域内离散气泡的运动行为研究。分析不同入口雷诺数下变径圆管内的流型流态、速度场以及气泡... 离散气泡在变径圆管内的变形动力学行为是指导气液两相介质输运及分离的重要理论。针对变径圆管结构,开展不同雷诺数及气泡粒径条件下的变径场域内离散气泡的运动行为研究。分析不同入口雷诺数下变径圆管内的流型流态、速度场以及气泡变形特性,探索变径圆管内流场特性与离散气泡间的相互作用规律。结果表明,气泡使其周围的流体速度变化,造成速度梯度增加,致使其周围流场的湍动能上升;此外,随着入口雷诺数增大,气泡在流场内的破碎位置越趋向于突扩截面处,当入口雷诺数Re=5.16×10^(3)时,气泡的破碎距离最短为16.09 mm;当雷诺数不变,气泡半径从2.5 mm增大至4.5 mm时,气泡的无量纲最大变形量由0.26增加至0.67,数值模拟结果与实验结果呈现出较好的一致性。 展开更多
关键词 变径圆管 气泡 流场特性 变形特性 运动行为
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“夸父一号”(ASO-S)卫星早期成果概述
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作者 甘为群 苏杨 +5 位作者 封莉 黄宇 黎辉 苏江涛 李瑛 刘锁 《科技导报》 北大核心 2025年第16期43-61,共19页
“夸父一号”卫星(ASO-S)是中国首颗综合性太阳探测专用卫星,在轨测试和试运行近1年,2023年9月底正式进入科学运行阶段。以“夸父一号”卫星的3台载荷数据利用为主线,重点介绍了卫星科学运行不到一年半时间(截至2025年2月)所取得的初步... “夸父一号”卫星(ASO-S)是中国首颗综合性太阳探测专用卫星,在轨测试和试运行近1年,2023年9月底正式进入科学运行阶段。以“夸父一号”卫星的3台载荷数据利用为主线,重点介绍了卫星科学运行不到一年半时间(截至2025年2月)所取得的初步观测研究成果:β型黑子衰减的磁对消作用、耀斑硬X射线准周期震荡的综合诊断、双视角硬X射线成像联合分析、360 nm白光耀斑的观测特性、Lyα卡林顿图等。未来,使用ASO-S观测数据,结合国内外其他先进太阳观测卫星数据,可联合开展多波段乃至立体观测研究,有望在“一磁两暴”的本质及关联性方面取得重要进展。 展开更多
关键词 夸父一号 太阳空间探测 太阳耀斑 日冕物质抛射 太阳磁场
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空间天气探源计划(探冕计划)
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作者 田晖 白先勇 +4 位作者 封莉 熊明 陈亚杰 侯振永 王亚敏 《空间科学学报》 北大核心 2025年第4期881-898,共18页
空间天气探源计划(探冕计划)将在同一颗卫星平台上实现对太阳和晚型恒星的同步观测,以揭示太阳系内外空间天气的源头——日冕和星冕的物理性质及爆发规律.卫星拟工作在约720 km高度的太阳同步轨道,同时对日冕和星冕开展长期、连续的观测... 空间天气探源计划(探冕计划)将在同一颗卫星平台上实现对太阳和晚型恒星的同步观测,以揭示太阳系内外空间天气的源头——日冕和星冕的物理性质及爆发规律.卫星拟工作在约720 km高度的太阳同步轨道,同时对日冕和星冕开展长期、连续的观测.通过搭载日面极紫外光谱仪、极紫外光谱日冕仪、恒星极紫外光谱仪、恒星极紫外测光望远镜等载荷,该计划将在三个方面取得重要突破:第一,通过首次开展全日面视场的日冕光谱观测,刻画日冕外流和爆发的源区特性,推动太阳系空间天气的精准预报;第二,通过填补当前太阳系外极紫外探测的空白,探明星冕爆发规律,从而开拓太阳系外空间天气的新疆域;第三,通过对太阳和其他恒星同步开展点源极紫外探测,并结合模型,建立空间天气影响行星宜居性的新认知. 展开更多
关键词 极紫外辐射 日冕 星冕 空间天气 行星宜居性
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