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氟诺哌齐结构和性质的密度泛函理论研究
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作者 孙婷婷 王德堂 《原子与分子物理学报》 CAS 北大核心 2025年第2期41-48,共8页
氟诺哌齐是一种新型的抗阿尔茨海默病临床候选药物,目前尚处于临床试验阶段;对氟诺哌齐进行密度泛函理论研究,有助于揭示其分子的性质和功能.在B3LYP/6-311+G(d,p)基组水平上,采用密度泛函理论(DFT)的方法优化氟诺哌齐的分子结构;在相... 氟诺哌齐是一种新型的抗阿尔茨海默病临床候选药物,目前尚处于临床试验阶段;对氟诺哌齐进行密度泛函理论研究,有助于揭示其分子的性质和功能.在B3LYP/6-311+G(d,p)基组水平上,采用密度泛函理论(DFT)的方法优化氟诺哌齐的分子结构;在相同基组水平下经过谐振频率分析,证实了12种分子构象的稳定结构,并确定了优势构型为DC20-1.根据Marcus理论,对其重组能进行模拟计算,得出氟诺哌齐分子不具备运输性质.通过前线轨道(FMO)分析,发现氟诺哌齐分子具有一定的电子跃迁能力和分子内反应活性,活性反应位点为C15、O28、C23和O26.根据红外光谱、紫外-可见吸收光谱模拟计算结果,对谱图数据进行了讨论分析,研究结果可作为氟诺哌齐表征和鉴别的参考依据. 展开更多
关键词 氟诺哌齐 密度泛函(DFT) 重组能 前线轨道(FMO) 红外光谱(IR) 紫外-可见吸收光谱(UV-Vis)
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腰椎“内聚式”对称减压人工诱导突出椎间盘自然回缩的减压机制
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作者 张春霖 侯曌华 +9 位作者 严旭 姜岩 付苏 宁永明 李东哲 董超 刘小康 王永魁 曹争明 杨腾跃 《中国组织工程研究》 CAS 北大核心 2025年第9期1810-1819,共10页
背景:腰椎间盘突出症传统手术通过“环”神经广泛式切除进行减压及摘除突出腰椎间盘,存在神经损伤造成瘫痪、腰椎失稳、突出复发、椎间隙感染以及邻椎病等多种风险及并发症。目的:提出腰椎“内聚式”对称减压人工诱导突出椎间盘自然回缩... 背景:腰椎间盘突出症传统手术通过“环”神经广泛式切除进行减压及摘除突出腰椎间盘,存在神经损伤造成瘫痪、腰椎失稳、突出复发、椎间隙感染以及邻椎病等多种风险及并发症。目的:提出腰椎“内聚式”对称减压人工诱导突出椎间盘自然回缩术,观察这种新术式的人工诱导突出椎间盘自然吸收现象及早期临床疗效,并分析其减压机制。方法:纳入2021年3月至2023年5月郑州大学第一附属医院骨科收治的腰椎间盘突出患者214例,其中对照组81例行保守治疗,试验组133例接受腰椎“内聚式”对称减压人工诱导突出椎间盘自然回缩术治疗。试验组术前、术后即刻(7-14 d)及术后早期(1年以上)分别使用MRI图像测量腰椎间盘突出的体积变化,CT图像测量腰椎棘突韧带复合体后移距离以及侧隐窝宽度和高度,日本骨科学会评分评估患者神经功能恢复情况。结果与结论:(1)对照组:保守治疗81例腰椎间盘突出患者共171个突出腰椎间盘,平均随访时间(22.7±23.1)个月;171个突出腰椎间盘就诊时及末次随访MRI测量突出腰椎间盘体积分别为(551.6±257.9)mm3和(792.2±330.4)mm3,体积平均增大率为(53.2±44.4)%,差异有显著性意义(P<0.001);171个突出腰椎间盘中有4个发生了自然回缩现象,吸收比为2.3%(4/171),吸收率为(24.5±9.9)%。(2)试验组:133例腰椎间盘突出患者共285个突出腰椎间盘。①术后即刻:所有患者均完成术后即刻随访,285个突出腰椎间盘中有229个发生回缩,吸收比为80.3%(229/285),平均吸收率为(21.5±20.9)%,显著及完全吸收占6.5%;上腰椎共70个突出腰椎间盘,吸收比为85.7%(60/70),平均吸收率为(23.1±19.5)%,最大吸收率为86.6%;下腰椎共215个突出腰椎间盘,吸收比为78.6%(169/215),平均吸收率为(21.0±21.3)%,最大吸收率为83.2%;上腰椎与下腰椎显著及完全吸收分别占5.7%和6.5%,无统计学差异(P>0.05);术后即刻棘突韧带复合体后移平均距离为(5.2±2.8)mm;术前和术后即刻相比,左侧、右侧侧隐窝的宽度、高度均无统计学差异(P>0.05);术后即刻日本骨科学会评分由术前(10.1±3.4)分提升至(17.0±4.8)分,术后即刻有效率达95.6%;②术后早期:其中46例患者完成术后早期随访,共101个突出腰椎间盘,吸收比为94%(95/101),平均吸收率为(36.9±23.7)%,显著及完全吸收占30.6%,最大吸收率为100%;101个突出腰椎间盘中有3个体积未发生变化,体积不变率为2.97%(3/101);101个突出腰椎间盘有3个突出椎间盘体积增大,增大比为2.97%(3/101),增大率为(18.5±18.4)%;日本骨科学会评分由术前(9.3±5.1)分提升至(23.5±4.0)分,优良率达93.4%。(3)对照组和试验组术后早期突出腰椎间盘吸收比分别为2.3%及85.9%,差异有显著性意义(P<0.001)。(4)并发症:试验组有2例发生切口渗液,延迟愈合,经换药等保守治疗切口愈合,且该组未发生神经损伤或死亡,也未再行二次手术。(5)结果显示,腰椎“内聚式”对称减压人工诱导突出椎间盘自然回缩术是一种可避免“环”神经广泛切除且可获得满意早期临床疗效的治疗腰椎间盘突出的新方法,不破坏腰椎关节突关节,也不改变侧隐窝基本解剖结构,完整保留突出腰椎间盘并可诱导其发生显著甚至完全的人工诱导突出椎间盘自然吸收;腰椎“内聚式”对称减压人工诱导突出椎间盘自然回缩术为腰椎间盘突出症的临床治疗提供了新的依据和方法。 展开更多
关键词 腰椎间盘突出症 人工诱导突出椎间盘自然回缩 对称减压 侧隐窝 自然吸收
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Multiple Tin Compounds Modified Carbon Fibers to Construct Heterogeneous Interfaces for Corrosion Prevention and Electromagnetic Wave Absorption 被引量:1
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作者 Zhiqiang Guo Di Lan +6 位作者 Zirui Jia Zhenguo Gao Xuetao Shi Mukun He Hua Guo Guanglei Wu Pengfei Yin 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期507-527,共21页
Currently,the demand for electromagnetic wave(EMW)absorbing materials with specific functions and capable of withstanding harsh environments is becoming increasingly urgent.Multi-component interface engineering is con... Currently,the demand for electromagnetic wave(EMW)absorbing materials with specific functions and capable of withstanding harsh environments is becoming increasingly urgent.Multi-component interface engineering is considered an effective means to achieve high-efficiency EMW absorption.However,interface modulation engineering has not been fully discussed and has great potential in the field of EMW absorption.In this study,multi-component tin compound fiber composites based on carbon fiber(CF)substrate were prepared by electrospinning,hydrothermal synthesis,and high-temperature thermal reduction.By utilizing the different properties of different substances,rich heterogeneous interfaces are constructed.This effectively promotes charge transfer and enhances interfacial polarization and conduction loss.The prepared SnS/SnS_(2)/SnO_(2)/CF composites with abundant heterogeneous interfaces have and exhibit excellent EMW absorption properties at a loading of 50 wt%in epoxy resin.The minimum reflection loss(RL)is−46.74 dB and the maximum effective absorption bandwidth is 5.28 GHz.Moreover,SnS/SnS_(2)/SnO_(2)/CF epoxy composite coatings exhibited long-term corrosion resistance on Q235 steel surfaces.Therefore,this study provides an effective strategy for the design of high-efficiency EMW absorbing materials in complex and harsh environments. 展开更多
关键词 Electrostatic spinning Component regulation Heterogeneous interfaces Electromagnetic wave absorption Corrosion protection
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基于热处理工艺的拖拉机发动机铝合金组织性能研究
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作者 汤金金 李好娜 《农机化研究》 北大核心 2025年第1期243-247,共5页
采用不同时长的热处理工艺,对拖拉机发动机铝合金组织性能进行了对比分析。结果表明:热处理后,铝合金性能得到了较大程度的提高,若优先考虑材料性能,则应该采用180℃×4 h的单级热处理时效;若优先考虑工艺效率和成本,则可以采用150... 采用不同时长的热处理工艺,对拖拉机发动机铝合金组织性能进行了对比分析。结果表明:热处理后,铝合金性能得到了较大程度的提高,若优先考虑材料性能,则应该采用180℃×4 h的单级热处理时效;若优先考虑工艺效率和成本,则可以采用150℃×1 h+170℃×1 h的双级热处理时效。 展开更多
关键词 热处理工艺 拖拉机 发动机 铝合金 组织性能
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智能传感技术在水肥一体系统中的应用研究
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作者 祝鹏 郭艳光 《农机化研究》 北大核心 2025年第2期176-180,共5页
以进一步提升水肥一体机系统的作业效率为目标,选取智能传感的监测技术,针对整机的监测控制与信号处理展开应用设计研究。考虑水肥一体机过程作业肥液融合的均匀性及系统各模块之间的协同性功能实现,结合微分补偿的传感数据算法处理方法... 以进一步提升水肥一体机系统的作业效率为目标,选取智能传感的监测技术,针对整机的监测控制与信号处理展开应用设计研究。考虑水肥一体机过程作业肥液融合的均匀性及系统各模块之间的协同性功能实现,结合微分补偿的传感数据算法处理方法,进行智能传感的水肥一体机架构布局,并匹配可执行的软件控制程序及硬件实施结构,进行实地传感应用监测与灌施控制作业试验。结果表明:水肥一体机系统的数据监测准确率可达95.25%,系统故障率相对降低3.79%,监测数据准确及时,能够确保系统各环节指令得到有效的调整与反馈,进而保证灌施土壤的含水稳定率相对提升7.87%,对于作物的稳定生长与产量提升有重要的参考价值。 展开更多
关键词 水肥一体机 智能传感 信号处理 微分补偿 数据监测准确率
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Structure and electrochemical performance of delafossite AgFeO_(2)nanoparticles for supercapacitor electrodes
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作者 Choulong Veann Thongsuk Sichumsaeng +3 位作者 Ornuma Kalawa Narong Chanlek Pinit Kidkhunthod Santi Maensiri 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期201-213,共13页
Delafossite AgFeO_(2)nanoparticles with a mixture of 2H and 3R phases were successfully fabricated by using a simple co-precipitation method.The resulting precursor was calcined at temperatures of 100,200,300,400,and ... Delafossite AgFeO_(2)nanoparticles with a mixture of 2H and 3R phases were successfully fabricated by using a simple co-precipitation method.The resulting precursor was calcined at temperatures of 100,200,300,400,and 500℃to obtain the delafossite AgFe0_(2)phase.The morphology and microstructure of the prepared AgFeO_(2)samples were characterized by using field emission scanning electron microscopy(FESEM),transmission electron microscopy(TEM),N_(2) adsorption/desorption,X-ray absorption spectroscopy(XAS),and Xray photoelectron spectroscopy(XPS)techniques.A three-electrode system was employed to investigate the electrochemical properties of the delafossite AgFeO_(2)nanoparticles in a 3 M KOH electrolyte.The delafossite AgFeO_(2)nanoparticles calcined at 100℃(AFO100)exhibited the highest surface area of 28.02 m^(2)·g^(-1)and outstanding electrochemical performance with specific capacitances of 229.71 F·g^(-1)at a current density of 1 A·g^(-1)and 358.32 F·g^(-1)at a scan rate of 2 mV·s^(-1).This sample also demonstrated the capacitance retention of 82.99% after 1000 charge/discharge cycles,along with superior specific power and specific energy values of 797.46 W·kg^(-1)and 72.74Wh·kg^(-1),respectively.These findings indicate that delafossite AgFeO_(2)has great potential as an electrode material for supercapacitor applications. 展开更多
关键词 NANOPARTICLES DELAFOSSITE electrochemical properties X-ray absorption spectroscopy CO-PRECIPITATION SUPERCAPACITOR
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Defects‑Rich Heterostructures Trigger Strong Polarization Coupling in Sulfides/Carbon Composites with Robust Electromagnetic Wave Absorption
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作者 Jiaolong Liu Siyu Zhang +14 位作者 Dan Qu Xuejiao Zhou Moxuan Yin Chenxuan Wang Xuelin Zhang Sichen Li Peijun Zhang Yuqi Zhou Kai Tao Mengyang Li Bing Wei Hongjing Wu Mengyang Li Bing Wei Hongjing Wu 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期528-547,共20页
Defects-rich heterointerfaces integrated with adjustable crystalline phases and atom vacancies,as well as veiled dielectric-responsive character,are instrumental in electromagnetic dissipation.Conventional methods,how... Defects-rich heterointerfaces integrated with adjustable crystalline phases and atom vacancies,as well as veiled dielectric-responsive character,are instrumental in electromagnetic dissipation.Conventional methods,however,constrain their delicate constructions.Herein,an innovative alternative is proposed:carrageenan-assistant cations-regulated(CACR)strategy,which induces a series of sulfides nanoparticles rooted in situ on the surface of carbon matrix.This unique configuration originates from strategic vacancy formation energy of sulfides and strong sulfides-carbon support interaction,benefiting the delicate construction of defects-rich heterostructures in M_(x)S_(y)/carbon composites(M-CAs).Impressively,these generated sulfur vacancies are firstly found to strengthen electron accumulation/consumption ability at heterointerfaces and,simultaneously,induct local asymmetry of electronic structure to evoke large dipole moment,ultimately leading to polarization coupling,i.e.,defect-type interfacial polarization.Such“Janus effect”(Janus effect means versatility,as in the Greek two-headed Janus)of interfacial sulfur vacancies is intuitively confirmed by both theoretical and experimental investigations for the first time.Consequently,the sulfur vacancies-rich heterostructured Co/Ni-CAs displays broad absorption bandwidth of 6.76 GHz at only 1.8 mm,compared to sulfur vacancies-free CAs without any dielectric response.Harnessing defects-rich heterostructures,this one-pot CACR strategy may steer the design and development of advanced nanomaterials,boosting functionality across diverse application domains beyond electromagnetic response. 展开更多
关键词 Defects-rich heterointerfaces Sulfides Polarization coupling Electromagnetic wave absorption
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Dendritic spine degeneration:a primary mechanism in the aging process
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作者 Gonzalo Flores Leonardo Aguilar-Hernández +3 位作者 Fernado García-Dolores Humberto Nicolini Andrea Judith Vázquez-Hernández Hiram Tendilla-Beltrán 《Neural Regeneration Research》 SCIE CAS 2025年第6期1696-1698,共3页
Recent reports suggest that aging is not solely a physiological process in living beings;instead, it should be considered a pathological process or disease(Amorim et al., 2022). Consequently, this process involves a w... Recent reports suggest that aging is not solely a physiological process in living beings;instead, it should be considered a pathological process or disease(Amorim et al., 2022). Consequently, this process involves a wide range of factors, spanning from genetic to environmental factors, and even includes the gut microbiome(GM)(Mayer et al., 2022). All these processes coincide at some point in the inflammatory process, oxidative stress, and apoptosis, at different degrees in various organs and systems that constitute a living organism(Mayer et al., 2022;AguilarHernández et al., 2023). 展开更多
关键词 AGING PROCESS STRESS
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Central role of altered phosphodiesterase 2-dependent signaling in the pathophysiology of cognition-based brain disorders
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作者 Asma Boulksibat Alessandra Tempio Barbara Bardoni 《Neural Regeneration Research》 SCIE CAS 2025年第8期2302-2303,共2页
The second messengers 3',5'-cyclic adenosine monophosphate(cAMP)and 3',5'-cyclic guanosine monophosphate(cGMP)modulate molecular pathways that are involved in a large variety of cellular processes.In t... The second messengers 3',5'-cyclic adenosine monophosphate(cAMP)and 3',5'-cyclic guanosine monophosphate(cGMP)modulate molecular pathways that are involved in a large variety of cellular processes.In the brain,these processes include neurogenesis,neuronal differentiation,activation and function of microglia,and synaptic plasticity,finally resulting in memory formation. 展开更多
关键词 formation processes finally
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Tailoring Light–Matter Interactions in Overcoupled Resonator for Biomolecule Recognition and Detection
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作者 Dongxiao Li Hong Zhou +2 位作者 Zhihao Ren Cheng Xu Chengkuo Lee 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期262-280,共19页
Plasmonic nanoantennas provide unique opportunities for precise control of light–matter coupling in surface-enhanced infrared absorption(SEIRA)spectroscopy,but most of the resonant systems realized so far suffer from... Plasmonic nanoantennas provide unique opportunities for precise control of light–matter coupling in surface-enhanced infrared absorption(SEIRA)spectroscopy,but most of the resonant systems realized so far suffer from the obstacles of low sensitivity,narrow bandwidth,and asymmetric Fano resonance perturbations.Here,we demonstrated an overcoupled resonator with a high plasmon-molecule coupling coefficient(μ)(OC-Hμresonator)by precisely controlling the radiation loss channel,the resonator-oscillator coupling channel,and the frequency detuning channel.We observed a strong dependence of the sensing performance on the coupling state,and demonstrated that OC-Hμresonator has excellent sensing properties of ultra-sensitive(7.25%nm^(−1)),ultra-broadband(3–10μm),and immune asymmetric Fano lineshapes.These characteristics represent a breakthrough in SEIRA technology and lay the foundation for specific recognition of biomolecules,trace detection,and protein secondary structure analysis using a single array(array size is 100×100μm^(2)).In addition,with the assistance of machine learning,mixture classification,concentration prediction and spectral reconstruction were achieved with the highest accuracy of 100%.Finally,we demonstrated the potential of OC-Hμresonator for SARS-CoV-2 detection.These findings will promote the wider application of SEIRA technology,while providing new ideas for other enhanced spectroscopy technologies,quantum photonics and studying light–matter interactions. 展开更多
关键词 Plasmonic nanoantennas Light-matter interaction Surface-enhanced infrared absorption Overcoupled BIOSENSING
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双偶氮苯-二苯并[b,i]噻蒽-[2,3-b]苯-5,7,12,14-四酮衍生物分子的二阶非线性光学性质 被引量:1
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作者 张宇红 李博 +4 位作者 陈自然 李渊 徐友辉 张莉萍 何旭东 《原子与分子物理学报》 CAS 北大核心 2025年第2期15-23,共9页
使用密度泛函理论(DFT)M06-2X方法、采用6-311+g(d,p)基组,分别对26个双偶氮-二苯并[b,i]噻蒽-[2,3-b]苯-5,7,12,14-四酮衍生物分子进行结构优化与频率计算;使用含时密度泛函理论(TD-DFT)TD-M06-2X方法计算了a1~d6分子的前线分子轨道与... 使用密度泛函理论(DFT)M06-2X方法、采用6-311+g(d,p)基组,分别对26个双偶氮-二苯并[b,i]噻蒽-[2,3-b]苯-5,7,12,14-四酮衍生物分子进行结构优化与频率计算;使用含时密度泛函理论(TD-DFT)TD-M06-2X方法计算了a1~d6分子的前线分子轨道与电子吸收光谱,采用有效场FF方法研究了二阶非线性光学性质(NLO).研究结果表明,26个噻蒽四酮类衍生物分子的能隙在1.33—2.02 eV范围,归属于有机半导体;最低能量吸收峰波长在601.8~609.5nm范围;在增大分子的二阶非线性光学系数β_(μ)(或β_(0))值方面,含相同偶氮苯基团或含不同偶氮苯基团分别引入到二苯并[b,i]噻蒽-[2,3-b]苯-5,7,12,14-四酮分子两侧的2,10位优于2,9位,在2,10位分别端接含推、拉基团的偶氮苯优于含相同给电子基团的偶氮苯.在偶氮苯苯环对位分别端接强吸电子基(-NO_(2))与强供电子基(如-N(CH_(3))_(2)、-N(Ph)_(3)、-N-苯基咔唑等)可增强体系的二阶非线性光学性能,获得性能良好的非线性光学材料. 展开更多
关键词 双偶氮 二苯并[b i]噻蒽-[2 3-b]苯-5 7 12 14-四酮 密度泛函理论 电子吸收光谱 二阶非线性光学性质
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Low‑Temperature Oxidation Induced Phase Evolution with Gradient Magnetic Heterointerfaces for Superior Electromagnetic Wave Absorption
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作者 Zizhuang He Lingzi Shi +6 位作者 Ran Sun Lianfei Ding Mukun He Jiaming Li Hua Guo Tiande Gao Panbo Liu 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期191-204,共14页
Gradient magnetic heterointerfaces have injected infinite vitality in optimizing impedance matching,adjusting dielectric/magnetic resonance and promoting electromagnetic(EM)wave absorption,but still exist a significan... Gradient magnetic heterointerfaces have injected infinite vitality in optimizing impedance matching,adjusting dielectric/magnetic resonance and promoting electromagnetic(EM)wave absorption,but still exist a significant challenging in regulating local phase evolution.Herein,accordion-shaped Co/Co_(3)O_(4)@N-doped carbon nanosheets(Co/Co_(3)O_(4)@NC)with gradient magnetic heterointerfaces have been fabricated via the cooperative high-temperature carbonization and lowtemperature oxidation process.The results indicate that the surface epitaxial growth of crystal Co_(3)O_(4) domains on local Co nanoparticles realizes the adjustment of magnetic-heteroatomic components,which are beneficial for optimizing impedance matching and interfacial polarization.Moreover,gradient magnetic heterointerfaces simultaneously realize magnetic coupling,and long-range magnetic diffraction.Specifically,the synthesized Co/Co_(3)O_(4)@NC absorbents display the strong electromagnetic wave attenuation capability of−53.5 dB at a thickness of 3.0 mm with an effective absorption bandwidth of 5.36 GHz,both are superior to those of single magnetic domains embedded in carbon matrix.This design concept provides us an inspiration in optimizing interfacial polarization,regulating magnetic coupling and promoting electromagnetic wave absorption. 展开更多
关键词 Magnetic heterointerfaces Phase evolution Interfacial polarization Magnetic coupling Electromagnetic wave absorption
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Advances in Graphene‑Based Electrode for Triboelectric Nanogenerator
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作者 Bin Xie Yuanhui Guo +7 位作者 Yun Chen Hao Zhang Jiawei Xiao Maoxiang Hou Huilong Liu Li Ma Xin Chen Chingping Wong 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期378-403,共26页
With the continuous development of wearable electronics,wireless sensor networks and other micro-electronic devices,there is an increasingly urgent need for miniature,flexible and efficient nanopower generation techno... With the continuous development of wearable electronics,wireless sensor networks and other micro-electronic devices,there is an increasingly urgent need for miniature,flexible and efficient nanopower generation technology.Triboelectric nanogenerator(TENG)technology can convert small mechanical energy into electricity,which is expected to address this problem.As the core component of TENG,the choice of electrode materials significantly affects its performance.Traditional metal electrode materials often suffer from problems such as durability,which limits the further application of TENG.Graphene,as a novel electrode material,shows excellent prospects for application in TENG owing to its unique structure and excellent electrical properties.This review systematically summarizes the recent research progress and application prospects of TENGs based on graphene electrodes.Various precision processing methods of graphene electrodes are introduced,and the applications of graphene electrode-based TENGs in various scenarios as well as the enhancement of graphene electrodes for TENG performance are discussed.In addition,the future development of graphene electrode-based TENGs is also prospectively discussed,aiming to promote the continuous advancement of graphene electrode-based TENGs. 展开更多
关键词 Triboelectric nanogenerator Precision processing Graphene electrode Self-powered sensor
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Study on the hydrogen absorption properties of a YGdTbDyHo rare-earth high-entropy alloy
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作者 Tongyue Li Ziliang Xie +5 位作者 Wenjiao Zhou Huan Tong Dawen Yang Anjia Zhang Yuan Wu Xiping Song 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期127-135,共9页
This study investigated the microstructure and hydrogen absorption properties of a rare-earth high-entropy alloy(HEA),YGdTbDyHo.Results indicated that the YGdTbDyHo alloy had a microstructure of equiaxed grains,with t... This study investigated the microstructure and hydrogen absorption properties of a rare-earth high-entropy alloy(HEA),YGdTbDyHo.Results indicated that the YGdTbDyHo alloy had a microstructure of equiaxed grains,with the alloy elements distributed homogeneously.Upon hydrogen absorption,the phase structure of the HEA changed from a solid solution with an hexagonal-close-packed(HCP)structure to a high-entropy hydride with an faced-centered-cubic(FCC)structure without any secondary phase precipitated.The alloy demonstrated a maximum hydrogen storage capacity of 2.33 H/M(hydrogen atom/metal atom)at 723 K,with an enthalpy change(ΔH)of-141.09 kJ·mol^(-1)and an entropy change(ΔS)of-119.14 J·mol^(-1)·K^(-1).The kinetic mechanism of hydrogen absorption was hydride nucleation and growth,with an apparent activation energy(E_(a))of 20.90 kJ·mol^(-1).Without any activation,the YGdTbDyHo alloy could absorb hydrogen quickly(180 s at 923 K)with nearly no incubation period observed.The reason for the obtained value of 2.33 H/M was that the hydrogen atoms occupied both tetrahedral and octahedral interstices.These results demonstrate the potential application of HEAs as a high-capacity hydrogen storage material with a large H/M ratio,which can be used in the deuterium storage field. 展开更多
关键词 RARE-EARTH high-entropy alloy hydrogen absorption capacity pressure–composition–temperature curves KINETICS
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Structural and microwave absorption properties of CoFe_(2)O_(4)/residual carbon composites
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作者 Yuanchun Zhang Shengtao Gao +3 位作者 Xingzhao Zhang Dacheng Ma Chuanlei Zhu Jun He 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期221-232,共12页
Electromagnetic interference,which necessitates the rapid advancement of substances with exceptional capabilities for bsorbing electromagnetic waves,is of urgent concern in contemporary society.In this work,CoFe_(2)O_... Electromagnetic interference,which necessitates the rapid advancement of substances with exceptional capabilities for bsorbing electromagnetic waves,is of urgent concern in contemporary society.In this work,CoFe_(2)O_(4)/residual carbon from coal gasification fine slag(CFO/RC)composites were created using a novel hydrothermal method.Various mechanisms for microwave absorption,including conductive loss,natural resonance,interfacial dipole polarization,and magnetic flux loss,are involved in these composites.Consequently,compared with pure residual carbon materials,this composite offers superior capabilities in microwave absorption.At 7.76GHz,the CFO/RC-2 composite achieves an impressive minimum reflection loss(RL_(min))of-43.99 dB with a thickness of 2.44 mm.Moreover,CFO/RC-3 demonstrates an effective absorption bandwidth(EAB)of up to 4.16 GHz,accompanied by a thickness of 1.18mm.This study revealed the remarkable capability of the composite to diminish electromagnetic waves,providing a new generation method for microwave absorbing materials of superior quality. 展开更多
关键词 coal gasification slag residual carbon hydrothermal method microwave absorption CoFe_(2)O_(4)
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Designing Electronic Structures of Multiscale Helical Converters for Tailored Ultrabroad Electromagnetic Absorption
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作者 Zhaobo Feng Chongbo Liu +7 位作者 Xin Li Guangsheng Luo Naixin Zhai Ruizhe Hu Jing Lin Jinbin Peng Yuhui Peng Renchao Che 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期439-455,共17页
Atomic-scale doping strategies and structure design play pivotal roles in tailoring the electronic structure and physicochemical property of electromagnetic wave absorption(EMWA)materials.However,the relationship betw... Atomic-scale doping strategies and structure design play pivotal roles in tailoring the electronic structure and physicochemical property of electromagnetic wave absorption(EMWA)materials.However,the relationship between configuration and electromagnetic(EM)loss mechanism has remained elusive.Herein,drawing inspiration from the DNA transcription process,we report the successful synthesis of novel in situ Mn/N co-doped helical carbon nanotubes with ultrabroad EMWA capability.Theoretical calculation and EM simulation confirm that the orbital coupling and spin polarization of the Mn–N4–C configuration,along with cross polarization generated by the helical structure,endow the helical converters with enhanced EM loss.As a result,HMC-8 demonstrates outstanding EMWA performance,achieving a minimum reflection loss of−63.13 dB at an ultralow thickness of 1.29 mm.Through precise tuning of the graphite domain size,HMC-7 achieves an effective absorption bandwidth(EAB)of 6.08 GHz at 2.02 mm thickness.Furthermore,constructing macroscale gradient metamaterials enables an ultrabroadband EAB of 12.16 GHz at a thickness of only 5.00 mm,with the maximum radar cross section reduction value reaching 36.4 dB m2.This innovative approach not only advances the understanding of metal–nonmetal co-doping but also realizes broadband EMWA,thus contributing to the development of EMWA mechanisms and applications. 展开更多
关键词 Metal-nonmetal co-doping 3d-2p orbital coupling Spin polarization Helical structure Broadband EM wave absorption
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Preparation of Co/S co-doped carbon catalysts for excellent methylene blue degradation
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作者 Haixu Li Haobo He +7 位作者 Tiannan Jiang Yunfei Du Zhichen Wu Liang Xu Xinjie Wang Xiaoguang Liu Wanhua Yu Wendong Xue 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期169-181,共13页
S and Co co-doped carbon catalysts were prepared via pyrolysis of MOF-71 and thiourea mixtures at 800℃at a mass ratio of MOF-71 to thiourea of 1:0.1 to effectively activate peroxymonosulfate(PMS)for methylene blue(MB... S and Co co-doped carbon catalysts were prepared via pyrolysis of MOF-71 and thiourea mixtures at 800℃at a mass ratio of MOF-71 to thiourea of 1:0.1 to effectively activate peroxymonosulfate(PMS)for methylene blue(MB)degradation.The effects of two different mixing routes were identified on the MB degradation performance.Particularly,the catalyst obtained by the alcohol solvent evaporation(MOF-AEP)mixing route could degrade 95.60%MB(50 mg/L)within 4 min(degradation rate:K=0.78 min^(-1)),which was faster than that derived from the direct grinding method(MOF-DGP,80.97%,K=0.39 min^(-1)).X-ray photoelectron spectroscopy revealed that the Co-S content of MOF-AEP(43.39at%)was less than that of MOF-DGP(54.73at%),and the proportion of C-S-C in MOF-AEP(13.56at%)was higher than that of MOF-DGP(10.67at%).Density functional theory calculations revealed that the adsorption energy of Co for PMS was -2.94 eV when sulfur was doped as C-S-C on the carbon skeleton,which was higher than that when sulfur was doped next to cobalt in the form of Co-S bond(-2.86 eV).Thus,the C-S-C sites might provide more contributions to activate PMS compared with Co-S.Furthermore,the degradation parameters,including pH and MOF-AEP dosage,were investigated.Finally,radical quenching experiments and electron paramagnetic resonance(EPR)measurements revealed that ^(1)O_(2)might be the primary catalytic species,whereas·O~(2-)might be the secondary one in degrading MB. 展开更多
关键词 advanced oxidation process alcohol solvent evaporation hydrogen bond S and Co co-doped carbon catalysts wastewater remediation
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Harnessing artificial intelligence for identifying conflicts of interest in research
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作者 Abdulqadir J Nashwan 《World Journal of Methodology》 2025年第1期6-8,共3页
This editorial explores the transformative potential of artificial intelligence(AI)in identifying conflicts of interest(COIs)within academic and scientific research.By harnessing advanced data analysis,pattern recogni... This editorial explores the transformative potential of artificial intelligence(AI)in identifying conflicts of interest(COIs)within academic and scientific research.By harnessing advanced data analysis,pattern recognition,and natural language processing techniques,AI offers innovative solutions for enhancing transparency and integrity in research.This editorial discusses how AI can automatically detect COIs,integrate data from various sources,and streamline reporting processes,thereby maintaining the credibility of scientific findings. 展开更多
关键词 Artificial intelligence Conflicts of interest TRANSPARENCY Research integrity Natural language processing
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Life-Cycle Bearing Capacity for Pre-Stressed T-beams Based on Full-Scale Destructive Test
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作者 Yushan Ye Tao Gao +4 位作者 Liankun Wang Junjie Ma Yingchun Cai Heng Liu Xiaoge Liu 《Structural Durability & Health Monitoring》 EI 2025年第1期145-166,共22页
To investigate the evolution of load-bearing characteristics of pre-stressed beams throughout their service life and to provide a basis for accurately assessing the actual working state of damaged pre-stressed concret... To investigate the evolution of load-bearing characteristics of pre-stressed beams throughout their service life and to provide a basis for accurately assessing the actual working state of damaged pre-stressed concrete T-beams,destructive tests were conducted on full-scale pre-stressed concrete beams.Based on the measurement and ana-lysis of beam deflection,strain,and crack development under various loading levels during the research tests,combined with the verification coefficient indicators specified in the codes,the verification coefficients of bridges at different stages of damage can be examined.The results indicate that the T-beams experience complete,incom-plete linear,and non-linear stages during the destructive test process.In the complete linear elastic stage,both the deflection and bottom strain verification coefficients comply with the specifications,indicating a good structural load-bearing capacity no longer adheres to the code’s requirements.In the non-linear stage,both coefficients exhi-bit a sharp increase,resulting in a further decrease in the structure’s load-bearing capacity.According to the pro-visions of the current code,the beam can be in the incomplete linear stage when both values fall within the code’s specified range.The strain verification coefficient sourced from the compression zone at the bottom of theflange is not recommended for assessing the bridge’s load-bearing capacity. 展开更多
关键词 Pre-stressed T-beams whole process destructive test bearing capacity verification coefficient
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基于图像处理技术的棚室番茄果实识别
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作者 陈翠琴 孟清 《农机化研究》 北大核心 2025年第1期189-193,共5页
我国番茄的产量居世界前列,种植的主要方式为棚室种植,大多采用人工采摘,成本高、效率低,不利于种植产业的发展。为此,提出了一种基于A-ENet模型的图像处理技术,用于棚室番茄果实的识别。A-ENet模型在EfficientNet运行时引入注意力机制... 我国番茄的产量居世界前列,种植的主要方式为棚室种植,大多采用人工采摘,成本高、效率低,不利于种植产业的发展。为此,提出了一种基于A-ENet模型的图像处理技术,用于棚室番茄果实的识别。A-ENet模型在EfficientNet运行时引入注意力机制,用于优化深度网络运算结果。EfficientNet通过调整、完善网络的宽度、深度等网络参数提升网络的识别准确率,同时在网络提取输入信号特征时引入注意力机制用于捕捉输入信号特征的权重信息,主动忽略环境因素对目标信号的干扰。A-ENet模型能够解决由于识别目标之间的细微差异产生的识别错误的问题,且能够减少随机环境因素对识别过程的干扰,提高识别成功率,对棚室番茄果实识别问题起到积极的影响作用。实验结果表明:所提出的基于图像处理技术的A-ENet模型能够构建出效率更高、鲁棒性更强的目标识别系统。 展开更多
关键词 番茄果实 EfficientNet 注意力机制 图像处理技术 深度网络
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