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EMD-YOLO:基于YOLOv8n改进的轻量化作物叶部病害检测算法 被引量:1
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作者 王斌兵 张亚利 +2 位作者 郑光 时雷 尹飞 《华中农业大学学报》 北大核心 2025年第4期181-191,共11页
为准确、快速地识别作物叶部病害,降低手工诊断成本,减少叶部病害对作物生长过程与产量的危害,提出一种基于YOLOv8n新型轻量级作物叶部病害检测算法EMD-YOLO。该算法结合多尺度空洞注意力MSDA、EffectiveSE注意力机制、DySample上采样以... 为准确、快速地识别作物叶部病害,降低手工诊断成本,减少叶部病害对作物生长过程与产量的危害,提出一种基于YOLOv8n新型轻量级作物叶部病害检测算法EMD-YOLO。该算法结合多尺度空洞注意力MSDA、EffectiveSE注意力机制、DySample上采样以及Wise-IoU损失函数。其中,多尺度空洞注意力MSDA结合多尺度空间卷积与注意力机制,提高多尺度特征提取效率;EffectiveSE强化特征选择,提升模型表示性能;DySample上采样保留重要特征,提高特征图分辨率和检测性能;Wise-IoU损失函数优化交并比(IoU)计算方式,提升模型定位精度。结果显示,EMD-YOLO的精确度、mAP@0.5、模型权重分别为96.3%、92.8%、4.85 MB,较基线模型YOLOv8n的精确度和平均精度均值分别提高3.0和3.6百分点,权重降低1.4 MB。结果表明,EMD-YOLO的泛化性良好,适用于移动端农作物叶部病害检测设备。 展开更多
关键词 深度学习 作物叶部病害 YOLOv8 effectivesE注意力机制 多尺度空洞注意力MSDA 轻量化算法
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基于YOLOv8n的学生课堂行为检测算法 被引量:1
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作者 胡敏 张伟 +3 位作者 姜念祖 林帅男 耿妍 赵瑞 《白城师范学院学报》 2025年第2期42-50,128,共10页
YOLO目标检测算法在当前的学生课堂行为检测领域占据着主导地位.由于课堂环境的复杂性,现有的YOLO模型在检测被遮挡的学生动作时存在检测精度不高、漏检和误检的情况.针对这一问题,提出了FCC-YOLO目标检测框架,使用FasterNet作为主干网... YOLO目标检测算法在当前的学生课堂行为检测领域占据着主导地位.由于课堂环境的复杂性,现有的YOLO模型在检测被遮挡的学生动作时存在检测精度不高、漏检和误检的情况.针对这一问题,提出了FCC-YOLO目标检测框架,使用FasterNet作为主干网络,引入CoordAtt(Coordinate Attention)注意力模块,并将EfficientNet的SE模块替换为EffectiveSE模块,与C2f模块融合为C2f-ECAB模块,以提取丰富的特征.实验结果表明,与YOLOv8n模型相比,本研究提出的算法在平均精度均值(mAP50)上提高了2.1%,召回率提高了3.4%,漏检的情况得到很好改善. 展开更多
关键词 YOLOv8n 课堂行为检测 FasterNet CoordAtt effectivesE
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基于改进YOLOv8s的矿井下安全帽佩戴检测 被引量:4
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作者 凌港 赵杰 +1 位作者 莫定界 张冬青 《计算机系统应用》 2025年第2期19-27,共9页
矿井下光照缺失、环境复杂,安全帽目标尺寸较小,导致一般目标检测模型对安全帽的检测效果不佳.针对上述问题,提出了一种基于改进YOLOv8s的矿井下安全帽佩戴检测模型.首先,将effectiveSE模块和YOLOv8s Neck层中的C2f模块相结合,设计得到... 矿井下光照缺失、环境复杂,安全帽目标尺寸较小,导致一般目标检测模型对安全帽的检测效果不佳.针对上述问题,提出了一种基于改进YOLOv8s的矿井下安全帽佩戴检测模型.首先,将effectiveSE模块和YOLOv8s Neck层中的C2f模块相结合,设计得到新的C2f-eSE模块,提高了网络结构的特征提取能力,并用Wise-EIoU损失函数替代CIoU损失函数,提高了模型的鲁棒性;其次,在检测头中引入空间和通道重建卷积模块SCConv,并根据参数共享思想设计了新的轻量化SPS检测头,降低了模型的参数量和计算复杂度;最后在模型中增加一层P2检测层,使模型的特征提取网络融入更多的浅层信息,提高了对小尺寸目标的检测能力.实验结果表明,改进后模型的mAP50指标提升了3.2%,参数量降低了1.6%,GFLOPs降低了5.6%. 展开更多
关键词 YOLOv8s 目标检测 矿井 effectivesE 安全帽检测
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A new horizon for neuroscience:terahertz biotechnology in brain research 被引量:1
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作者 Zhengping Pu Yu Wu +2 位作者 Zhongjie Zhu Hongwei Zhao Donghong Cui 《Neural Regeneration Research》 SCIE CAS 2025年第2期309-325,共17页
Terahertz biotechnology has been increasingly applied in various biomedical fields and has especially shown great potential for application in brain sciences.In this article,we review the development of terahertz biot... Terahertz biotechnology has been increasingly applied in various biomedical fields and has especially shown great potential for application in brain sciences.In this article,we review the development of terahertz biotechnology and its applications in the field of neuropsychiatry.Available evidence indicates promising prospects for the use of terahertz spectroscopy and terahertz imaging techniques in the diagnosis of amyloid disease,cerebrovascular disease,glioma,psychiatric disease,traumatic brain injury,and myelin deficit.In vitro and animal experiments have also demonstrated the potential therapeutic value of terahertz technology in some neuropsychiatric diseases.Although the precise underlying mechanism of the interactions between terahertz electromagnetic waves and the biosystem is not yet fully understood,the research progress in this field shows great potential for biomedical noninvasive diagnostic and therapeutic applications.However,the biosafety of terahertz radiation requires further exploration regarding its two-sided efficacy in practical applications.This review demonstrates that terahertz biotechnology has the potential to be a promising method in the field of neuropsychiatry based on its unique advantages. 展开更多
关键词 biological effect brain NEURON NEUROPSYCHIATRY NEUROSCIENCE non-thermal effect terahertz imaging terahertz radiation terahertz spectroscopy terahertz technology
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Utilizing engineered extracellular vesicles as delivery vectors in the management of ischemic stroke:a special outlook on mitochondrial delivery 被引量:1
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作者 Jiali Chen Yiyang Li +7 位作者 Xingping Quan Jinfen Chen Yan Han Li Yang Manfei Zhou Greta Seng Peng Mok Ruibing Wang Yonghua Zhao 《Neural Regeneration Research》 SCIE CAS 2025年第8期2181-2198,共18页
Ischemic stroke is a secondary cause of mortality worldwide,imposing considerable medical and economic burdens on society.Extracellular vesicles,serving as natural nanocarriers for drug delivery,exhibit excellent bioc... Ischemic stroke is a secondary cause of mortality worldwide,imposing considerable medical and economic burdens on society.Extracellular vesicles,serving as natural nanocarriers for drug delivery,exhibit excellent biocompatibility in vivo and have significant advantages in the management of ischemic stroke.However,the uncertain distribution and rapid clearance of extracellular vesicles impede their delivery efficiency.By utilizing membrane decoration or by encapsulating therapeutic cargo within extracellular vesicles,their delivery efficacy may be greatly improved.Furthermore,previous studies have indicated that microvesicles,a subset of large-sized extracellular vesicles,can transport mitochondria to neighboring cells,thereby aiding in the restoration of mitochondrial function post-ischemic stroke.Small extracellular vesicles have also demonstrated the capability to transfer mitochondrial components,such as proteins or deoxyribonucleic acid,or their sub-components,for extracellular vesicle-based ischemic stroke therapy.In this review,we undertake a comparative analysis of the isolation techniques employed for extracellular vesicles and present an overview of the current dominant extracellular vesicle modification methodologies.Given the complex facets of treating ischemic stroke,we also delineate various extracellular vesicle modification approaches which are suited to different facets of the treatment process.Moreover,given the burgeoning interest in mitochondrial delivery,we delved into the feasibility and existing research findings on the transportation of mitochondrial fractions or intact mitochondria through small extracellular vesicles and microvesicles to offer a fresh perspective on ischemic stroke therapy. 展开更多
关键词 delivery engineering extracellular vesicles identification ischemic stroke isolation MITOCHONDRIA targeting strategy therapeutic effects
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Novel Methodologies for Preventing Crack Propagation in Steel Gas Pipelines Considering the Temperature Effect 被引量:2
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作者 Nurlan Zhangabay Ulzhan Ibraimova +4 位作者 Marco Bonopera Ulanbator Suleimenov Konstantin Avramov Maryna Chernobryvko Aigerim Yessengali 《Structural Durability & Health Monitoring》 EI 2025年第1期1-23,共23页
Using the software ANSYS-19.2/Explicit Dynamics,this study performedfinite-element modeling of the large-diameter steel pipeline cross-section for the Beineu-Bozoy-Shymkent gas pipeline with a non-through straight crac... Using the software ANSYS-19.2/Explicit Dynamics,this study performedfinite-element modeling of the large-diameter steel pipeline cross-section for the Beineu-Bozoy-Shymkent gas pipeline with a non-through straight crack,strengthened by steel wire wrapping.The effects of the thread tensile force of the steel winding in the form of single rings at the crack edges and the wires with different winding diameters and pitches were also studied.The results showed that the strengthening was preferably executed at a minimum value of the thread tensile force,which was 6.4%more effective than that at its maximum value.The analysis of the influence of the winding dia-meters showed that the equivalent stresses increased by 32%from the beginning of the crack growth until the wire broke.The increment in winding diameter decelerated the disclosure of the edge crack and reduced its length by 8.2%.The analysis of the influence of the winding pitch showed that decreasing the distance between the winding turns also led to a 33.6%reduction in the length of the straight crack and a 7.9%reduction in the maximum stres-ses on the strengthened pipeline cross-section.The analysis of the temperature effect on the pipeline material,within a range from-40℃to+50℃,resulted in a crack length change of up to 5.8%.As the temperature dropped,the crack length decreased.Within such a temperature range,the maximum stresses were observed along the cen-tral area of the crack,which were equal to 413 MPa at+50℃and 440 MPa at-40℃.The results also showed that the presence of the steel winding in the pipeline significantly reduced the length of crack propagation up to 8.4 times,depending on the temperature effect and design parameters of prestressing.This work integrated the existing methods for crack localization along steel gas pipelines. 展开更多
关键词 Crack propagation finite-element internal pressure PRESTRESSING steel gas pipeline temperature effect
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Complexation and Fluorescence Enhancement of Bay-site Carboxyl Modified Perylene Dimide with Calcium Ion 被引量:3
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作者 GU Dandan ZHAO Haoru +4 位作者 JIANG Xiaoze QI Haohan LIAO Zuogui CHEN Jia SUN Bin 《发光学报》 北大核心 2025年第3期474-485,共12页
Bay-site carboxyl functionalized perylene diimide derivative 1,7-COOH-PDI-C_(12)(PDI-COOH)was synthesized and distinct enhanced fluorescence was observed through combining with calcium ion(Ca^(2+))in THF/H_(2)O soluti... Bay-site carboxyl functionalized perylene diimide derivative 1,7-COOH-PDI-C_(12)(PDI-COOH)was synthesized and distinct enhanced fluorescence was observed through combining with calcium ion(Ca^(2+))in THF/H_(2)O solution.The assembly and fluorescence behavior of PDI-COOH/Ca^(2+)were studied in detail by changing hydration state with different concentrations.Based on the differences in assembly morphology and stoichiometric ratios of PDICOOH/Ca^(2+),we proposed the fluorescence emission mechanism of PDI-COOH/Ca^(2+)in THF/H_(2)O and THF,respectively.This work reveals a novel strategy of aggregated state fluorescence enhancement and reminds us of the important role of water in molecular fluorescence emission and assembly. 展开更多
关键词 carboxyl functionalized fluorescence behavior perylene diimide photoinduced electron transfer effect calcium ion
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Microstructural evolution during the progressive transformation-induced plasticity effect in a Fe-0.1C-5Mnmedium manganese steel 被引量:1
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作者 Mei Zhang Wenhao Li +3 位作者 Yangfei Chen Yang Jiang Xiaofei Guo Han Dong 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第2期369-379,共11页
The microstructural evolution of a cold-rolled and intercritical annealed medium-Mn steel(Fe-0.10C-5Mn)was investigated during uniaxial tensile testing.In-situ observations under scanning electron microscopy,transmiss... The microstructural evolution of a cold-rolled and intercritical annealed medium-Mn steel(Fe-0.10C-5Mn)was investigated during uniaxial tensile testing.In-situ observations under scanning electron microscopy,transmission electron microscopy,and X-ray diffraction analysis were conducted to characterize the progressive transformation-induced plasticity process and associated fracture initiation mechanisms.These findings were discussed with the local strain measurements via digital image correlation.The results indicated that Lüders band formation in the steel was limited to 1.5%strain,which was mainly due to the early-stage martensitic phase transformation of a very small amount of the less stable large-sized retained austenite(RA),which led to localized stress concentrations and strain hardening and further retardation of yielding.The small-sized RA exhibited high stability and progressively transformed into martensite and contributed to a stably extended Portevin-Le Chatelier effect.The volume fraction of RA gradually decreased from 26.8%to 8.2%prior to fracture.In the late deformation stage,fracture initiation primarily occurred at the austenite/martensite and ferrite/martensite interfaces and the ferrite phase. 展开更多
关键词 medium-Mn steel retained austenite progressive transformation-induced plasticity effect local strain fracture initiation
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P,N co-doped hollow carbon nanospheres prepared by micellar copolymerization for increased hydrogen evolution in alkaline water 被引量:1
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作者 HAN Yi-meng XIONG Hao +2 位作者 YANG Jia-ying WANG Jian-gan XU Fei 《新型炭材料(中英文)》 北大核心 2025年第1期211-221,共11页
The design of cost-effective and efficient metal-free carbon-based catalysts for the hydrogen evolution reaction(HER)is of great significance for increasing the production of clean hydrogen by the electrolysis of alka... The design of cost-effective and efficient metal-free carbon-based catalysts for the hydrogen evolution reaction(HER)is of great significance for increasing the production of clean hydrogen by the electrolysis of alkaline water.Precise control of the electronic structure by heteroatom doping has proven to be efficient for increasing catalytic activity.Nevertheless,both the structural characteristics and the underlying mechanism are not well understood,especially for doping with two different atoms,thus limiting the use of these catalysts.We report the production of phosphorus and nitrogen co-doped hollow carbon nanospheres(HCNs)by the copolymerization of pyrrole and aniline at a Triton X-100 micelle-interface,followed by doping with phytic acid and carbonization.The unique pore structure and defect-rich framework of the HCNs expose numerous active sites.Crucially,the combined effect of graphitic nitrogen and phosphorus-carbon bonds modulate the local electronic structure of adjacent C atoms and facilitates electron transfer.As a res-ult,the HCN carbonized at 1100°C exhibited superior HER activity and an outstanding stability(70 h at a current density of 10 mA cm^(−2))in alkaline water,because of the large number of graphitic nitrogen and phosphorus-carbon bonds. 展开更多
关键词 Alkaline hydrogen evolution ELECTROCATALYSTS Hollow carbon nanospheres Dual atoms doping Combined effect
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Variations in quantifying patient reported outcome measures to estimate treatment effect 被引量:1
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作者 Sathish Muthu Srujun Vadranapu 《World Journal of Methodology》 2025年第2期44-53,共10页
In the practice of healthcare,patient-reported outcomes(PROs)and PRO measures(PROMs)are used as an attempt to observe the changes in complex clinical situations.They guide us in making decisions based on the evidence ... In the practice of healthcare,patient-reported outcomes(PROs)and PRO measures(PROMs)are used as an attempt to observe the changes in complex clinical situations.They guide us in making decisions based on the evidence regarding patient care by recording the change in outcomes for a particular treatment to a given condition and finally to understand whether a patient will benefit from a particular treatment and to quantify the treatment effect.For any PROM to be usable in health care,we need it to be reliable,encapsulating the points of interest with the potential to detect any real change.Using structured outcome measures routinely in clinical practice helps the physician to understand the functional limitation of a patient that would otherwise not be clear in an office interview,and this allows the physician and patient to have a meaningful conver-sation as well as a customized plan for each patient.Having mentioned the rationale and the benefits of PROMs,understanding the quantification process is crucial before embarking on management decisions.A better interpretation of change needs to identify the treatment effect based on clinical relevance for a given condition.There are a multiple set of measurement indices to serve this effect and most of them are used interchangeably without clear demarcation on their differences.This article details the various quantification metrics used to evaluate the treatment effect using PROMs,their limitations and the scope of usage and implementation in clinical practice. 展开更多
关键词 Patient-reported outcome measures Treatment effect Minimal clinical important difference Patient-accepted symptom state Minimum detectable change ORTHOPEDICS
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Luteolin and glycyrrhetinic exert cooperative effect on liver cancer by selfassembling into carrier-free nanostructures 被引量:2
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作者 Lanlan Zong Yuxin Dai +6 位作者 Jiahao Xu Chaofeng Qiao Yao Qi Chengyuan Ma Hong Li Xiaobin Pang Xiaohui Pu 《Chinese Chemical Letters》 2025年第10期447-452,共6页
Liver cancer is the fourth cause of cancer-related deaths and the primary cause of death in patients with compensated cirrhosis.In recent years,the role of traditional Chinese medicine in the treatment of liver cancer... Liver cancer is the fourth cause of cancer-related deaths and the primary cause of death in patients with compensated cirrhosis.In recent years,the role of traditional Chinese medicine in the treatment of liver cancer has attracted more and more attention and recognition.Luteolin(LUT)and glycyrrhetinic(GA)are natural compounds extracted from Chinese herbal medicine.LUT exhibits various biological activity including anti-inflammatory,antibacterial,antiviral,anti-tumor,and neuroprotective effects.GA significantly inhibits the growth and metastasis of cancer cells.However,the low water solubility of both compounds hinders their clinical applications.In this study,rod-shaped nanoparticles(NPs)self-assembled from LUT and GA were designed to enhance drug solubility and tumor-targeting capability.We verified that the assembly mechanism of the NPs was π-π stacking.These NPs significantly inhibited the proliferation of liver cancer cells while had no significant effect on normal liver cells.In a mouse model of liver cancer,these NPs demonstrated superior tumor-targeting ability due to the enhanced permeability and retention effect,and the affinity of GA for liver cancer cells,resulting in better therapeutic efficacy with lower systemic toxicity.Results of network pharmacology analysis showed that LUT and GA respectively targeted estrogen receptor 1(ESR1)protein and cyclin-dependent kinase 1(CDK1)protein to corporately induce tumor cell cycle arrest,which induced the inhibition of tumor cell proliferation.In conclusion,this study provides a novel reference for the treatment of liver cancer. 展开更多
关键词 LUTEOLIN Glycyrrhetinic Nanoself-assembly Synergistic effect Liver cancer
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Advancements in metal-iodine batteries: progress and perspectives 被引量:2
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作者 Zi-Zhou Shen Dian-Heng Yu +6 位作者 Hong-Ye Ding Yi Peng Yi-Hao Chen Jing-Wen Zhao Heng-Yue Xu Xiao-Tian Guo Huan Pang 《Rare Metals》 2025年第4期2143-2179,共37页
Metal-iodine batteries have attracted widespread attention due to their long cycle life,high energy density,remarkable charging capability and low self-discharge rate.Nevertheless,this development is hampered by the c... Metal-iodine batteries have attracted widespread attention due to their long cycle life,high energy density,remarkable charging capability and low self-discharge rate.Nevertheless,this development is hampered by the challenges of the iodine cathode and metal anode,including the hydrogen evolution reaction(HER),sluggish kinetics,shuttle effect of polyiodine ion at the cathode and dendrite formation,corrosion and passivation at the anode.This review summarizes recent developments in metaliodine batteries,including zinc-iodine batteries,lithiumiodine batteries,sodium-iodine batteries,etc.The challenges in the cathode,anode,electrolyte and separator of metal-iodine batteries are discussed,along with the corresponding design and synthesis strategies and specific methods to improve the electrochemical performance.Selecting appropriate cathode hosts,constructing surface protective layers,adding anode additives,making threedimensional anode designs and employing better electrolytes and functional separators to obstruct the production and shuttling of polyiodine ions are highlighted.Finally,future guidelines and directions for the development of metal-iodine batteries are proposed. 展开更多
关键词 Metal-iodine battery Shuttle effect Metal dendrite Functional modification
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Accurate prediction of magnetocaloric effect in NiMn-based Heusler alloys by prioritizing phase transitions through explainable machine learning 被引量:2
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作者 Yi-Chuan Tang Kai-Yan Cao +7 位作者 Ruo-Nan Ma Jia-Bin Wang Yin Zhang Dong-Yan Zhang Chao Zhou Fang-Hua Tian Min-Xia Fang Sen Yang 《Rare Metals》 2025年第1期639-651,共13页
With the rapid development of artificial intelligence,magnetocaloric materials as well as other materials are being developed with increased efficiency and enhanced performance.However,most studies do not take phase t... With the rapid development of artificial intelligence,magnetocaloric materials as well as other materials are being developed with increased efficiency and enhanced performance.However,most studies do not take phase transitions into account,and as a result,the predictions are usually not accurate enough.In this context,we have established an explicable relationship between alloy compositions and phase transition by feature imputation.A facile machine learning is proposed to screen candidate NiMn-based Heusler alloys with desired magnetic entropy change and magnetic transition temperature with a high accuracy R^(2)≈0.98.As expected,the measured properties of prepared NiMn-based alloys,including phase transition type,magnetic entropy changes and transition temperature,are all in good agreement with the ML predictions.As well as being the first to demonstrate an explicable relationship between alloy compositions,phase transitions and magnetocaloric properties,our proposed ML model is highly predictive and interpretable,which can provide a strong theoretical foundation for identifying high-performance magnetocaloric materials in the future. 展开更多
关键词 NiMn-based Heusler materials Phase transition-type Machine learning Magnetocaloric effect Composition design
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Interstitial-oxygen-inducedγ-phase precipitation and martensitic transformation behavior in Ni-Mn-Sn-Co alloy prepared through binder jetting and sintering 被引量:1
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作者 Shijiang Zhong Mingfang Qian +5 位作者 Xinxin Shen Shuhe Gong Liangbo Sun Ping Shen Xuexi Zhang Lin Geng 《Journal of Materials Science & Technology》 2025年第11期272-277,共6页
1.Introduction.Ni-Mn-X(X=Ga,In,Sn,or Sb)Heusler alloys have versatile properties[1-4],such as shape memory effect[1],superelastic-ity[5],magnetocaloric effect[3],elastocaloric effect[6],and even multicaloric effect[7]... 1.Introduction.Ni-Mn-X(X=Ga,In,Sn,or Sb)Heusler alloys have versatile properties[1-4],such as shape memory effect[1],superelastic-ity[5],magnetocaloric effect[3],elastocaloric effect[6],and even multicaloric effect[7],that indicate their potential for use in actu-ators,sensors,micropumps,energy harvesters,and solid-state re-frigeration[8-10].Among the alloys,Ni-Mn-Sn-based alloys are environment-friendly and cost-effective[6,7,11],and hence,they have received widespread attention. 展开更多
关键词 phase precipitation martensitic transformation SINTERING Ni Mn Sn Co alloy shape memory effect superelastic ity magnetocaloric effect elastocaloric effect interstitial oxygen binder jetting multicaloric effect
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Assessment of seismic intensity and seismic performance of buildings in the M7.9 Myanmar earthquake 被引量:3
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作者 Sun Baitao Yan Jiaqi +2 位作者 Yang Yongqiang Chen Xiangzhao Sun Menghan 《Earthquake Engineering and Engineering Vibration》 2025年第3期641-652,共12页
Dispatched by the Chinese government,a multidisciplinary team of 30 researchers collaborated with a team from Myanmar to conduct a 14-day on-site investigation.The work encompassed seismic intensity assessments,field ... Dispatched by the Chinese government,a multidisciplinary team of 30 researchers collaborated with a team from Myanmar to conduct a 14-day on-site investigation.The work encompassed seismic intensity assessments,field surveys,and loss evaluations.The paper focuses on the intensity distribution and structural damage characteristics of the 2025 M7.9 Myanmar earthquake,yielding the following key findings.(1)The seismogenic fault rupture propagated in a nearly N-S direction,with a surface rupture length of approximately 450 km.The seismic impact zone exhibited an elongated N-S distribution and a shorter E-W span,distributed like a belt around the seismogenic fault.(2)Within the seismic impact zones,existing buildings comprised five primary structural types,with timber(bamboo)structures constituting the largest proportion(≈80%in rural areas,≈50%in urban areas).The relatively low disaster losses and casualties were primarily attributable to the good seismic performance and low damage ratio of timber(bamboo)structures across varying intensity zones.(3)An anomalous zone of intensityⅨwas located at the boundary between intensityⅥandⅦregions in Nay Pyi Taw.Here,ridge topography combined with soft soil layers significantly amplified ground motion,exacerbating structural damage.(4)Directional effects of ground motion were observed,with the structural damage phenomena and peak ground acceleration(PGA)values in the N-S direction exceeding those in the E-W direction.This validates that the maximum PGA distribution of strike-slip fault earthquakes aligns with the fault strike.The research is expected to provide technical support for post-disaster reconstruction planning,site selection,and disaster mitigation strategies in Myanmar. 展开更多
关键词 M7.9 Myanmar earthquake seismic intensity timber(bamboo)structure directional effects of ground motion strike-slip fault
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Progress in Flexoelectric Effect Research and Related Applications 被引量:1
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作者 Pengwen Guo Mengmeng Jia +3 位作者 Di Guo Tianling Ren Zhong Lin Wang Junyi Zhai 《SmartSys》 2025年第1期39-46,共8页
The flexoelectric effect refers to the electromechanical coupling between electric polarization and mechanical strain gradient.It universally exists in a variety of materials in any space group,such as liquid crystals... The flexoelectric effect refers to the electromechanical coupling between electric polarization and mechanical strain gradient.It universally exists in a variety of materials in any space group,such as liquid crystals,dielectrics,biological materials,and semiconductors.Because of its unique size effect,nanoscale flexoelectricity has shown novel phenomena and promising applications in electronics,optronics,mechatronics,and photovoltaics.In this review,we provide a succinct report on the discovery and development of the flexoelectric effect,focusing on flexoelectric materials and related applications.Finally,we discuss recent flexoelectric research progress and still‐unsolved problems. 展开更多
关键词 electric polarization flexoelectric effect flexotronics size effect strain gradient
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Failure mechanisms of electronic detonators subjected to high impact loading in rock drilling and blasting 被引量:2
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作者 Zhendong Leng Yong Fan +2 位作者 Wenbo Lu Qidong Gao Guangdong Yang 《International Journal of Coal Science & Technology》 2025年第1期214-227,共14页
In rock drilling and blasting,the misfire of electronic detonators will not only affect the rock fragmentation result but also bring serious potential safety hazards to engineering construction.An accurate and compreh... In rock drilling and blasting,the misfire of electronic detonators will not only affect the rock fragmentation result but also bring serious potential safety hazards to engineering construction.An accurate and comprehensive understanding of the failure mechanisms of electronic detonators subjected to impact loading is of great significance to the reliability design and field safety use of electronic detonators.The spatial distribution characteristics and failure modes of misfired electronic detonators under different application scenarios are statistically analysed.The results show that under high impact loads,electronic detonators will experience failure phenomena such as rupture of the fuse head,fracture of the bridge wire,falling off of the solder joint,chip module damage and insufficient initiation energy after deformation.The lack of impact resistance is the primary cause of misfire of electronic detonators.Combined with the underwater impact resistance test and the impact load test in the adjacent blasthole on site,the formulas of the impact failure probability of the electronic detonator under different stress‒strength distribution curves are deduced.The test and evaluation method of the impact resistance of electronic detonators based on stress‒strength interference theory is proposed.Furthermore,the impact failure model of electronic detonators considering the strength degradation effect under repeated random loads is established.On this basis,the failure mechanism of electronic detonators under different application environments,such as open-pit blasting and underground blasting,is revealed,which provides scientific theory and methods for the reliability analysis,design and type selection of electronic detonators in rock drilling and blasting. 展开更多
关键词 Rock blasting Electronic detonator Impact loading Stress‒strength interference theory Strength degradation effect
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危险化学品运输车辆停车场火灾爆炸事故分析 被引量:2
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作者 杨鹏 刁旭 +1 位作者 高康 窦站 《化工安全与环境》 2025年第2期18-23,29,共7页
基于某化工园区危险化学品停车场运输车辆火灾爆炸事故,利用事故树和事件树分析法对该类事故发生的原因和预防措施等进行分析;然后利用Effects软件构建汽油罐车、液化石油气罐车、液化天然气罐车发生泄漏扩散和火灾爆炸的事故场景,分别... 基于某化工园区危险化学品停车场运输车辆火灾爆炸事故,利用事故树和事件树分析法对该类事故发生的原因和预防措施等进行分析;然后利用Effects软件构建汽油罐车、液化石油气罐车、液化天然气罐车发生泄漏扩散和火灾爆炸的事故场景,分别研究各罐车内物料发生泄漏、蒸发、扩散、燃烧爆炸的过程,并将模拟计算结果进行对比分析。主要得出:(1)汽油、液化石油气、液化天然气燃烧后产生的最大热辐射分别为38.2 kW/m2、204.9 kW/m2、130 kW/m2,根据热辐射的判断准则给出了人员长时间能够承受的安全距离,分别为42 m、662 m、585 m;(2)液化石油气、液化天然气爆炸产生的冲击波超压最大值分别为0.28MPa、0.39MPa,根据超压准则给出了人员免受伤害的安全距离,分别为50 m、208 m。 展开更多
关键词 危险化学品 运输车辆停车场 火灾爆炸 事故分析 后果模拟 Effects软件
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Exploration of the copper–niobium composite superconducting cavities for pursuing extremely high operational stability at IMP 被引量:1
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作者 Shi-Chun Huang Yuan He +16 位作者 Long Peng Chun-Long Li Sheng-Xue Zhang Meng-Xin Xu Zi-Qin Yang Hao Guo Lu-Bei Liu Ping-Ran Xiong An-Dong Wu Qing-Wei Chu Xiao-Fei Niu Teng Tan Zhi-Jun Wang Jun-Hui Zhang Sheng-Hu Zhang Hong-Wei Zhao Wen-Long Zhan 《Nuclear Science and Techniques》 2025年第5期19-29,共11页
Theoretically,copper–niobium(Cu-Nb)composite superconducting cavities have excellent potential for high thermal and mechanical stability.They can appropriately exploit the high-gradient surface processing recipes dev... Theoretically,copper–niobium(Cu-Nb)composite superconducting cavities have excellent potential for high thermal and mechanical stability.They can appropriately exploit the high-gradient surface processing recipes developed for the bulk niobium(Nb)cavity and the thick copper(Cu)layer’s high thermal conductivity and rigidity,thereby enhancing the operational stability of the bulk Nb cavities.This study conducted a global review of the technical approaches employed for fabricating Cu-Nb composite superconducting cavities.We explored Cu-Nb composite superconducting cavities based on two technologies at the Institute of Modern Physics,Chinese Academy of Sciences(IMP,CAS),including their manufacturing processes,radio-frequency(RF)characteristics,and mechanical performance.These cavities exhibit robust mechanical stability.First,the investigation of several 1.3 GHz single-cell elliptical cavities using the Cu-Nb composite sheets indicated that the wavy structure at the Cu-Nb interface influenced the reliable welding of the Cu-Nb composite parts.We observed the generation and trapping of magnetic flux density during the T_c crossing of Nb in cooldown process.The cooling rates during the T_c crossing of Nb exerted a substantial impact on the performance of the cavities.Furthermore,we measured and analyzed the surface resistance R_(s)attributed to the trapped magnetic flux induced by the Seebeck effect after quenching events.Second,for the first time,a low-beta bulk Nb cavity was plated with Cu on its outer surface using electroplating technology.We achieved a high peak electric field E_(pk)of~88.8 MV/m at 2 K and the unloaded quality factor Q_(0)at the E_(pk)of 88.8 MV/m exceeded 1×10^(10).This demonstrated that the electroplating Cu on the bulk Nb cavity is a practical method of developing the Cu-Nb composite superconducting cavity with superior thermal stability.The results presented here provide valuable insights for applying Cu-Nb composite superconducting cavities in superconducting accelerators with stringent operational stability requirements. 展开更多
关键词 Superconducting radio-frequency cavities Cu-Nb composite Mechanical and thermal stability Thermoelectrical effect Magnetic flux trapping effect
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Independent and interactive effects of N and P additions on foliar P fractions in evergreen forests of southern China 被引量:1
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作者 Qingquan Meng Zhijuan Shi +3 位作者 Zhengbing Yan Hans Lambers Yan Luo Wenxuan Han 《Forest Ecosystems》 2025年第1期66-73,共8页
Fertilization or atmospheric deposition of nitrogen(N)and phosphorus(P)to terrestrial ecosystems can alter soil N(P)availability and the nature of nutrient limitation for plant growth.Changing the allocation of leaf P... Fertilization or atmospheric deposition of nitrogen(N)and phosphorus(P)to terrestrial ecosystems can alter soil N(P)availability and the nature of nutrient limitation for plant growth.Changing the allocation of leaf P fractions is potentially an adaptive strategy for plants to cope with soil N(P)availability and nutrient-limiting conditions.However,the impact of the interactions between imbalanced anthropogenic N and P inputs on the concentrations and allocation proportions of leaf P fractions in forest woody plants remains elusive.We conducted a metaanalysis of data about the concentrations and allocation proportions of leaf P fractions,specifically associated with individual and combined additions of N and P in evergreen forests,the dominant vegetation type in southern China where the primary productivity is usually considered limited by P.This assessment allowed us to quantitatively evaluate the effects of N and P additions alone and interactively on leaf P allocation and use strategies.Nitrogen addition(exacerbating P limitation)reduced the concentrations of leaf total P and different leaf P fractions.Nitrogen addition reduced the allocation to leaf metabolic P but increased the allocation to other fractions,while P addition showed opposite trends.The simultaneous additions of N and P showed an antagonistic(mutual suppression)effect on the concentrations of leaf P fractions,but an additive(summary)effect on the allocation proportions of leaf P fractions.These results highlight the importance of strategies of leaf P fraction allocation in forest plants under changes in environmental nutrient availability.Importantly,our study identified critical interactions associated with combined N and P inputs that affect leaf P fractions,thus aiding in predicting plant acclimation strategies in the context of intensifying and imbalanced anthropogenic nutrient inputs. 展开更多
关键词 Anthropogenic nutrient inputs Individual and combined effects Interactive effects Leaf phosphorus fractions Nitrogen and phosphorus additions Nutrient-utilization strategies Woody plants
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