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Synergistically enhanced ORR and HER performance on Co-N-C coupled in-situ generated PtCo intermetallic

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Journal of Energy Chemistry 2025年第1期100卷 721-729页

作者： Guanyu Luo Min Song Lulu An xiao huang Qian Zhang Chenhao Zhang Tao Shen Shuang Wang Deli Wang Key Laboratory of Material Chemistry for Energy Conversion and Storage (Huazhong University of Science and Technology) Ministry of Education School of Chemistry and Chemical Engineering Huazhong University of Science and Technology

Integrating multi-scale sites in a composite catalyst is vital to realize efficient ***,a synergistic composite catalyst consisting of Co atomic sites and in-situ generated PtCo intermetallic compounds （IMCs）(o-PtCo@CoNC) is proposed through Co pre-anchoring and subsequent impregnation-reduction *** loading of Co atoms provides a chance for in-situ generating PtCo ordered intermetallic *** remaining Co single atoms and PtCo IMCs construct synergistic electrocatalytic *** from the ordered structure,synergistic effect of Pt Co IMCs and Co single atoms,o-PtCo@CoNC exhibits excellent electrocatalytic performance for oxygen reduction reaction （ORR） and hydrogen evolution reaction （HER） with mass activity of 1.21 A mgPt-1（at 0.9 V） and5.70 A mgPt-1（at an overpotential of 100 mV）,***,o-PtCo@CoNC delivers negligible loss of half-wave potential and overpotential during long-term stability test in acid solutions,with 13 mV decay after 50,000 potential cycles for ORR and a 2.7 mV decay after 20,000 potential cycles for *** integration strategy of single-atomic sites coupled IMCs paves the way for enhancing the activity and durability of Pt-based electrocatalysts.

关键词： Synergistic effect Intermetallics Single atomic sites Oxygen reduction reaction Hydrogen evolution reaction

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弹射座椅冲击过程数值模拟方法

机械设计 2007年第3期24卷 54-57页

作者：韩冰吴立言黄孝武刘更西北工业大学机电学院陕西西安710072 江汉航空救生装备工业公司湖北襄樊441000

以某型弹射座椅为研究对象,建立有限元模型进行座椅结构的冲击动力学仿真。分析了座椅结构在冲击载荷作用下的响应规律,指出了可能导致座椅弹射失败的薄弱环节。仿真过程中总结了结构冲击的一般规律,并分析了阻尼在类似的冲击过程中对... 详细信息

以某型弹射座椅为研究对象,建立有限元模型进行座椅结构的冲击动力学仿真。分析了座椅结构在冲击载荷作用下的响应规律,指出了可能导致座椅弹射失败的薄弱环节。仿真过程中总结了结构冲击的一般规律,并分析了阻尼在类似的冲击过程中对响应结果的影响。为以后复杂结构的冲击动力学研究提供了参考依据。

关键词：弹射座椅有限元冲击动力学阻尼

Vertical gradients of neutral winds observed by ICON and estimated by the Horizontal Wind Model during the geomagnetic storm on August 26−28,2021

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Earth and Planetary Physics 2025年第1期9卷 69-80页

作者： JiaWei wu Chao Xiong YuYang huang YunLiang Zhou Department of Space Physics School of Electronic InformationHubei Luojia LaboratoryWuhan UniversityWuhan 430072China

The Michelson Interferometer for Global High-resolution Thermospheric Imaging(MIGHTI)onboard the Ionospheric Connection Explorer(ICON)satellite offers the opportunity to investigate the altitude profile of thermospheric *** this study,we used the red-line measurements of MIGHTI to compare with the results estimated by Horizontal Wind Model 14(HWM14).The data selected included both the geomagnetic quiet period(December 2019 to August 2022)and the geomagnetic storm on August 26-28,*** the geomagnetic quiet period,the estimations of neutral winds from HWM14 showed relatively good agreement with the observations from *** to the ICON observations,near the equator,zonal winds reverse from westward to eastward at around 06:00 local time(LT)at higher altitudes,and the stronger westward winds appear at later LTs at lower *** around 16:00 LT,eastward winds at 300 km reverse to westward,and vertical gradients of zonal winds similar to those at sunrise hours can be *** the middle latitudes,zonal winds reverse about 2-4 h *** winds vary more significantly than zonal winds with seasonal and latitudinal *** to the ICON observations,in the northern low latitudes,vertical reversals of meridional winds are found at 08:00-13:00 LT from 300 to 160 km and at around 18:00 LT from 300 to 200 km during the June *** reversals of meridional winds are found at 04:00-07:00 LT from 300 to 160 km and at 22:00-02:00 LT from 270 to 200 km during the December *** the southern low latitudes,meridional wind reversals occur at 08:00-11:00 LT from 200 to 160 km and at 21:00-02:00 LT from 300 to 200 km during the June *** the December solstice,reversals of the meridional wind appear at 20:00-01:00 LT below 200 km and at 06:00-11:00 LT from 300 to 160 *** the northern middle latitudes,the northward winds are dominant at 08:00-14:00 LT at 230 km during the June *** winds persist until

关键词： horizontal neutral winds vertical gradients Ionospheric Connection Explorer satellite Horizontal Wind Model 14 geomagnetic storm

经济不确定性与公司投资——基于中国上市公司数据实证分析

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海南大学学报（人文社会科学版） 2020年第5期38卷 34-44页

作者：黄孝武任亚奇余杰中南财经政法大学金融学院产业升级与区域金融湖北省协同创新中心湖北武汉430073 南京大学商学院江苏南京210093

经济不确定性是影响企业投资的重要因素。通过大维宏观经济数据和动态因子模型可以计算出宏观经济不确定性,并利用Fama-French三因子模型可将宏观经济不确定性指标转化为公司经济不确定性。利用1998—2016年59个中国宏观经济变量数据和... 详细信息

经济不确定性是影响企业投资的重要因素。通过大维宏观经济数据和动态因子模型可以计算出宏观经济不确定性,并利用Fama-French三因子模型可将宏观经济不确定性指标转化为公司经济不确定性。利用1998—2016年59个中国宏观经济变量数据和中国上市公司数据,对经济不确定性与公司投资之间关系的实证结果表明,随着公司经济不确定性的增加,公司的投资会显著降低,而且对非国有公司、市场化程度高地区的公司更是如此。相关稳健性检验也证实了这一结论的可靠性。进一步研究表明,由于金融摩擦导致的融资约束在其中发挥了中介效应。这些结论为理解公司投资策略提供了一个视角,也为理解经济不确定性对公司投资的影响提供了经验证据。

关键词：经济不确定性公司经济不确定性动态因子模型公司投资融资约束

Enhancement of motor functional recovery in thoracic spinal cord injury: voluntary wheel running versus forced treadmill exercise

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Neural Regeneration Research 2025年第3期20卷 836-844页

作者： Do-Hun Lee Dan Cao Younghye Moon Chen Chen Nai-Kui Liu xiao-Ming Xu Wei wu Spinal Cord and Brain Injury Research Group Stark Neurosciences Research InstituteIndiana University School of MedicineIndianapolisINUSA Department of Neurological Surgery Indiana University School of MedicineIndianapolisINUSA Department of Neuroscience Baylor College of MedicineHoustonTXUSA

Spinal cord injury necessitates effective rehabilitation strategies, with exercise therapies showing promise in promoting recovery. This study investigated the impact of rehabilitation exercise on functional recovery and morphological changes following thoracic contusive spinal cord injury. After a 7-day recovery period after spinal cord injury, mice were assigned to either a trained group(10 weeks of voluntary running wheel or forced treadmill exercise) or an untrained group. Bi-weekly assessments revealed that the exercise-trained group, particularly the voluntary wheel exercise subgroup, displayed significantly improved locomotor recovery, more plasticity of dopaminergic and serotonin modulation compared with the untrained group. Additionally, exercise interventions led to gait pattern restoration and enhanced transcranial magnetic motor-evoked potentials. Despite consistent injury areas across groups, exercise training promoted terminal innervation of descending axons. In summary, voluntary wheel exercise shows promise for enhancing outcomes after thoracic contusive spinal cord injury, emphasizing the role of exercise modality in promoting recovery and morphological changes in spinal cord injuries. Our findings will influence future strategies for rehabilitation exercises, restoring functional movement after spinal cord injury.

关键词： behavioral assessment motor function neural plasticity running wheel exercise spinal cord injury treadmill exercise voluntary exercise

miRNA-21-5p is an important contributor to the promotion of injured peripheral nerve regeneration using hypoxia-pretreated bone marrow-derived neural crest cells

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Neural Regeneration Research 2025年第1期20卷 277-290页

作者： Meng Cong Jing-Jing Hu Yan Yu xiao-Li Li xiao-Ting Sun Li-Ting Wang Xia wu Ling-Jie Zhu xiao-Jia Yang Qian-Ru He Fei Ding Hai-Yan Shi School of Medicine Nantong UniversityNantongJiangsu ProvinceChina Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education and Coinnovation Center of Neuroregeneration Nantong UniversityNantongJiangsu ProvinceChina Department of Physiology Jiangsu Health Vocational CollegeNanjingJiangsu ProvinceChina Department of Pathology Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina

Our previous study found that rat bone marrow–derived neural crest cells(acting as Schwann cell progenitors)have the potential to promote long-distance nerve ***-based therapy can enhance peripheral nerve repair and regeneration through paracrine bioactive factors and intercellular ***,the complex contributions of various types of soluble cytokines and extracellular vesicle cargos to the secretome remain *** investigate the role of the secretome and extracellular vesicles in repairing damaged peripheral nerves,we collected conditioned culture medium from hypoxia-pretreated neural crest cells,and found that it significantly promoted the repair of sensory neurons damaged by oxygen-glucose *** mRNA expression of trophic factors was highly expressed in hypoxia-pretreated neural crest *** performed RNA sequencing and bioinformatics analysis and found that miR-21-5p was enriched in hypoxia-pretreated extracellular vesicles of neural crest ***,to further clarify the role of hypoxia-pretreated neural crest cell extracellular vesicles rich in miR-21-5p in axonal growth and regeneration of sensory neurons,we used a microfluidic axonal dissociation model of sensory neurons in vitro,and found that hypoxia-pretreated neural crest cell extracellular vesicles promoted axonal growth and regeneration of sensory neurons,which was greatly dependent on loaded ***,we constructed a miR-21-5p-loaded neural conduit to repair the sciatic nerve defect in rats and found that the motor and sensory functions of injured rat hind limb,as well as muscle tissue morphology of the hind limbs,were obviously *** findings suggest that hypoxia-pretreated neural crest extracellular vesicles are natural nanoparticles rich in ***-21-5p is one of the main contributors to promoting nerve regeneration by the neural crest cell *** helps to explain the mechanism of action of the secretome and e

关键词： axotomy cell-free therapy conditioned medium extracellular vesicles hypoxic preconditioning microRNA oxygen-glucose deprivation peripheral nerve injury Schwann cell precursors

第三方农产品质量检测和追溯认证外包服务模式研究

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广东农业科学 2012年第19期39卷 192-195页

作者：刘晓君黄小武凡小燕吴智冬广州神农信息技术服务有限公司广东广州510635

在我国以批发市场为节点的集散式农产品生产与流通模式下,农产品质量监管存在诸多困境。为此,提出了建立基于产业利益链和市场化运作机制的第三方农产品质量检测和追溯认证外包服务的创新模式,旨在对农产品产业链全过程的质量安全控制... 详细信息

在我国以批发市场为节点的集散式农产品生产与流通模式下,农产品质量监管存在诸多困境。为此,提出了建立基于产业利益链和市场化运作机制的第三方农产品质量检测和追溯认证外包服务的创新模式,旨在对农产品产业链全过程的质量安全控制和提高各环节监管能力。实践证明,该模式具有推广意义。

关键词：农产品质量检测农产品安全质量追溯认证第三方服务

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一种改进的乳酸脱氢酶同工酶染色法

生物化学与生物物理进展 2000年第4期27卷 438-439页

作者：赵赣张守全黄肖武詹福建何安行华南农业大学生物技术学院广州510642 华南农业大学动物科学系广州510642

以N 甲基吩嗪甲基硫酸盐 (PMS)为介体 ,使乳酸脱氢酶 (LDH)同工酶催化反应产生的NADH将铁氰化钾还原为亚铁氰化钾 ,利用亚铁氰化钾与三氯化铁反应生成普鲁士蓝的性质 ,实现对乳酸脱氢酶同工酶进行染色的目的 .

关键词：乳酸脱氢酶同工酶铁氰化钾三氯化铁染色法

Flexible Strain Sensors with Ultra‑High Sensitivity and Wide Range Enabled by Crack‑Modulated Electrical Pathways

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Nano-Micro Letters 2025年第3期17卷 246-264页

作者： Yunzhao Bai Yunlei Zhou Xuanyu wu Mengfei Yin Liting Yin Shiyuan Qu Fan Zhang Kan Li YongAn huang State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074People’s Republic of China Flexible Electronics Research Center Huazhong University of Science and TechnologyWuhan 430074People’s Republic of China Hangzhou Institute of Technology Xidian UniversityHangzhou 311200People’s Republic of China School of Mechano‑Electronic Engineering Xidian UniversityXi’an 710071People’s Republic of China Department of Aerospace and Mechanical Engineering University of Southern CaliforniaLos AngelesCA 90089USA

This study presents a breakthrough in flexible strain sensor technology with the development of an ultrahigh sensitivity and wide-range sensor,addressing the critical challenge of reconciling sensitivity with measurement *** by the structure of bamboo slips,we introduce a novel approach that utilises liquid metal to modulate the electrical pathways within a cracked platinum fabric *** resulting sensor demonstrates a gauge factor greater than 108 and a strain measurement capability exceeding 100%.The integration of patterned liquid metal enables customisable tuning of the sensor’s response,while the porous fabric structure ensures superior comfort and air permeability for the *** design not only optimises the sensor’s performance but also enhances the electrical stability that is essential for practical *** systematic investigation,we reveal the intrinsic mechanisms governing the sensor’s response,offering valuable insights for the design of wearable strain *** sensor’s exceptional performance across a spectrum of applications,from micro-strain to large-strain detection,highlights its potential for a wide range of real-world uses,demonstrating a significant advancement in the field of flexible electronics.

关键词： Flexible strain sensor Fabric Crack Response regulation Epidermal device