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High-dense nanocrystalline W-based alloy prepared by hot isostatic pressing with uniform microstructure, ultrahigh hardness and good thermal stability

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Tungsten 2025年第1期7卷 120-136页

作者： Zao-Ming Wu Lin he Lin-Sen Ye Xiao-Feng Yang jia-jia Zhang Hong-Bo Lei Institute of Materials China Academy of Engineering Physics

High-density uniform microstructure nanocrystalline W-10wt.% Cr-5wt.% Y（W-10Cr-5Y） alloy with an average grain size of 85 nm and a relative density of 99.8% was successfully prepared.W-Cr-Y alloys with different amounts of second-phase particles were prepared by high-energy ball milling and hot isostatic pressing *** effects of composition design,ball milling parameters,and sintering parameters on the microstructure of W-Cr-Y alloys were studied.A feasible technology for controlling the synthesis of high-density nanocrystalline W-based alloys has been *** microstructure analysis of nanocrystalline W-10Cr-5Y alloy shows that there are two types of doping in the second phase:intergranular doping and intragranular *** "uniform distribution YOx-rich particles" effectively suppresses the grain growth of W and leads to the formation of nanocrystalline W-10Cr-5Y alloy.W-10Cr-5Y has an ultra-high hardness,with a Vickers hardness of 1312±12 kgf·***-temperature annealing treatment shows that W-10Cr-5Y has good thermal stability at 1000 and1100℃,as demonstrated by the comparison of Vickers hardness and grain size between annealed and unannealed alloys.

关键词： Hot isostatic pressing Microstructure Nanocrystalline tungsten Thermal stability Vickers hardness

Recent Strategies and Advances in Hydrogel‑Based Delivery Platforms for Bone Regeneration

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Nano-Micro Letters 2025年第3期17卷 389-439页

作者： Xiao Wang jia Zeng Donglin Gan Kun Ling Mingfang he jianshu Li Yongping Lu Scientific and Technological Innovation Center for Biomedical Materials and Clinical Research Guangyuan Key Laboratory of Multifunctional Medical HydrogelGuangyuan Central HospitalGuangyuan 628000People’s Republic of China jiangsu Collaborative Innovation Center of Biomedical Functional Materials Jiangsu Key Laboratory of Bio‑Functional MaterialsSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023People’s Republic of China College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065People’s Republic of China

Bioactive molecules have shown great promise for effectively regulating various bone formation processes,rendering them attractive therapeutics for bone ***,the widespread application of bioactive molecules is limited by their low accumulation and short half-lives in *** have emerged as ideal carriers to address these challenges,offering the potential to prolong retention times at lesion sites,extend half-lives in vivo and mitigate side effects,avoid burst release,and promote adsorption under physiological *** review systematically summarizes the recent advances in the development of bioactive molecule-loaded hydrogels for bone regeneration,encompassing applications in cranial defect repair,femoral defect repair,periodontal bone regeneration,and bone regeneration with underlying ***,this review discusses the current strategies aimed at improving the release profiles of bioactive molecules through stimuli-responsive delivery,carrier-assisted delivery,and sequential ***,this review elucidates the existing challenges and future directions of hydrogel encapsulated bioactive molecules in the field of bone regeneration.

关键词： Hydrogel Bone regeneration Bioactive molecules Drug delivery Nano-/microscale carriers

Passive activity enhances residual control ability in patients with complete spinal cord injury

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Neural Regeneration Research 2025年第8期20卷 2337-2347页

作者： Yanqing Xiao Mingming Gao Zejia he jia Zheng Hongming Bai jia-Sheng Rao Guiyun Song Wei Song Xiaoguang Li Beijing Key Laboratory for Biomaterials and Neural Regeneration Beijing Advanced Innovation Center for Biomedical EngineeringSchool of Biological Science and Medical EngineeringBeihang UniversityBeijingChina Department of Rehabilitation Evaluation China Rehabilitation Research CenterBeijingChina Cardiac Center Beijing Children’s HospitalCapital Medical UniversityBeijingChina The State Key Laboratory of Virtual Reality Technology and Systems Beihang UniversityBeijingChina Department of Rehabilitation Engineering China Rehabilitation Science InstituteBeijingChina

Patients with complete spinal cord injury retain the potential for volitional muscle activity in muscles located below the spinal injury ***,because of prolonged inactivity,initial attempts to activate these muscles may not effectively engage any of the remaining neurons in the descending pathway.A previous study unexpectedly found that a brief clinical round of passive activity significantly increased volitional muscle activation,as measured by surface *** this study,we further explored the effect of passive activity on surface electromyographic signals during volitional control tasks among individuals with complete spinal cord *** patients with chronic complete thoracic spinal cord injury were *** electromyography data from eight major leg muscles were acquired and compared before and after the passive activity *** results indicated that the passive activity led to an increased number of activated volitional muscles and an increased frequency of *** the cumulative root mean square of surface electromyography amplitude for volitional control of movement showed a slight increase after passive activity,the difference was not statistically *** findings suggest that brief passive activity may enhance the ability to initiate volitional muscle activity during surface electromyography tasks and underscore the potential of passive activity for improving residual motor control among patients with motor complete spinal cord injury.

关键词： complete spinal cord injury cycle training epidural electrical stimulation motor training passive activity physiological state spinal cord circuit surface electromyography volitional control task

2010-2019年中国艾滋病流行时空分布特征

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中华疾病控制杂志 2022年第5期26卷 541-546页

作者：何佳晋袁璐吴超浙江大学公共卫生学院杭州310058 潍坊医学院公共卫生学院潍坊261053 浙江大学公共管理学院杭州310058

目的分析2010-2019年中国AIDS发病数据的时空分布特征。方法AIDS发病数据来源于中国卫生年鉴和公共卫生科学数据中心,人口学数据来源于国家统计局。使用线性趋势χ^(2)检验和分级地图分析AIDS流行趋势,运用GeoDa 1.18软件进行全局和局... 详细信息

目的分析2010-2019年中国AIDS发病数据的时空分布特征。方法AIDS发病数据来源于中国卫生年鉴和公共卫生科学数据中心,人口学数据来源于国家统计局。使用线性趋势χ^(2)检验和分级地图分析AIDS流行趋势,运用GeoDa 1.18软件进行全局和局部空间自相关分析,运用SaTScan 9.7软件进行时空扫描分析。结果中国AIDS发病率线性趋势χ^(2)检验值为30.432(P<0.001);分级地图显示中国发病率地理分布差异较大,表现出“南重北轻、西高东低”的空间格局。全局空间自相关分析得到Moran’s I值从2010年的0.196上升至2019年的0.383,表明存在空间正自相关性,且相关程度不断增强。局部空间自相关分析结果表明,广西壮族自治区和云南省一直为高-高聚集模式,2012年贵州省由低-高聚集转变成高-高聚集,2014年河南省由高-低聚集转变为低-低聚集,2016-2019年高-高聚集模式新增湖南省、四川省和重庆市。时空扫描分析共探测出3个聚集区域,在时间和空间上具有一定的聚集性。结论中国AIDS疫情在空间上具有地域差异性,空间聚集性逐年增强,且西南地区高-高聚齐区域不断扩大,根据时空特征分析制定针对性防控策略,可达到区域协作和合理分配资源的作用。

关键词：艾滋病发病率空间自相关时空分析

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一种改进的速度加姿态匹配快速传递对准算法

中国惯性技术学报 2017年第1期25卷 17-21页

作者：夏家和张金亮雷宏杰西安飞行自动控制研究所西安710065

给出了一种针对工程应用的改进快速传递对准算法。推导了速度及主子惯导z轴安装误差角量测构造方法,给出了基于速度加z轴安装误差角量测的降阶快速传递对准滤波器模型。通过仿真测试了降阶滤波模型的对准性能。最后利用协方差分析方法... 详细信息

给出了一种针对工程应用的改进快速传递对准算法。推导了速度及主子惯导z轴安装误差角量测构造方法,给出了基于速度加z轴安装误差角量测的降阶快速传递对准滤波器模型。通过仿真测试了降阶滤波模型的对准性能。最后利用协方差分析方法针对性分析了航向误差对主要未建模误差的敏感程度,结果显示:摇翼机动条件下30 s时航向误差收敛到0.1°内,航向误差主要受主惯导航向误差及z轴挠曲变形的影响,对主惯导数据时间延迟不敏感。该方法兼具传统速度加姿态匹配算法的优点,又避开了其在摇翼机动时对时间延迟、挠曲变形敏感的缺点。

关键词：捷联惯导传递对准安装失准角协方差分析

Multiple Tin Compounds Modified Carbon Fibers to Construct heterogeneous Interfaces for Corrosion Prevention and Electromagnetic Wave Absorption

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Nano-Micro Letters 2025年第1期17卷 507-527页

作者： Zhiqiang Guo Di Lan Zirui jia Zhenguo Gao Xuetao Shi Mukun he Hua Guo Guanglei Wu Pengfei Yin College of Science Sichuan Agricultural UniversityYa’an 625014People’s Republic of China School of Materials Science and Engineering Hubei University of Automotive TechnologyShiyan 442002People’s Republic of China Institute of Materials for Energy and Environment State Key Laboratory of Bio‑Fibers and Eco‑TextilesCollege of Materials Science and EngineeringQingdao UniversityQingdao 266071People’s Republic of China Shaanxi Key Laboratory of Macromolecular Science and Technology School of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’anShaanxi 710072People’s Republic of China

Currently,the demand for electromagnetic wave(EMW)absorbing materials with specific functions and capable of withstanding harsh environments is becoming increasingly ***-component interface engineering is considered an effective means to achieve high-efficiency EMW ***,interface modulation engineering has not been fully discussed and has great potential in the field of EMW *** this study,multi-component tin compound fiber composites based on carbon fiber(CF)substrate were prepared by electrospinning,hydrothermal synthesis,and high-temperature thermal *** utilizing the different properties of different substances,rich heterogeneous interfaces are *** effectively promotes charge transfer and enhances interfacial polarization and conduction *** 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 *** minimum reflection loss(RL)is−46.74 dB and the maximum effective absorption bandwidth is 5.28 ***,SnS/SnS_(2)/SnO_(2)/CF epoxy composite coatings exhibited long-term corrosion resistance on Q235 steel ***,this study provides an effective strategy for the design of high-efficiency EMW absorbing materials in complex and harsh environments.

关键词： Electrostatic spinning Component regulation heterogeneous interfaces Electromagnetic wave absorption Corrosion protection

鲁棒均值-CVaR投资组合模型及实证:基于安全准则的视角

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运筹与管理 2016年第6期25卷 128-132,138页

作者：刘家和金秀苑莹郑红东北大学工商管理学院辽宁沈阳110819

考虑证券市场的不确定性,将资产的收益率看成区间随机变量。利用鲁棒优化方法,构建鲁棒均值-CVaR投资组合模型。采用对偶理论,将鲁棒均值-CVaR投资组合模型转换为线性规划问题,降低了模型的求解难度,有助于计算大规模的资产组合。进一步... 详细信息

考虑证券市场的不确定性,将资产的收益率看成区间随机变量。利用鲁棒优化方法,构建鲁棒均值-CVaR投资组合模型。采用对偶理论,将鲁棒均值-CVaR投资组合模型转换为线性规划问题,降低了模型的求解难度,有助于计算大规模的资产组合。进一步地,考虑投资者的安全性需求,在模型中引入最大违反概率,控制模型的保守程度,并直观反映投资者的安全性要求。采用实证的方法,研究模型的有效性。结果表明:鲁棒均值-CVaR投资组合模型具有较好的稳健性,且满足投资者的安全性要求,在实际的投资决策中具有可行性。

关键词：金融工程投资组合模型鲁棒优化安全准则

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地应力测试数据高可靠性处理系统研究

煤炭科学技术 2015年第1期43卷 41-44页

作者：贾金河邢长海天地科技股份有限公司开采设计事业部北京100013 内蒙古伊泰煤炭股份有限公司内蒙古鄂尔多斯017000

为了提高空心包体地应力数据处理的效率、可靠性和实用性,从软件可视化、数据可靠性校验和应力表示形式3方面进行了研究。基于Windows平台开发了空心包体地应力数据处理软件,提出利用测试数据的冗余进行数据可靠性校验的方法,提供了3种... 详细信息

为了提高空心包体地应力数据处理的效率、可靠性和实用性,从软件可视化、数据可靠性校验和应力表示形式3方面进行了研究。基于Windows平台开发了空心包体地应力数据处理软件,提出利用测试数据的冗余进行数据可靠性校验的方法,提供了3种形式的全应力状态表示方法。软件包含输入输出模块、数据检索模块、数据处理模块;用实例展示了简洁、友好的可视化输入输出界面;用计算实例证明软件能够快速、有效地剔除不合理数据;提供了水平最大应力形式表示的全应力状态,适合采矿工程的需要。基于Windows平台的空心包体地应力可视化数据处理软件使用简便、效率高,能快速剔除非正常测试数据,避免错误的计算结果,提高地应力测试结果的可靠性。

关键词：空心包体应力计数据处理软件开发地应力

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一种铝型材的无铬电化学抛光工艺

轻合金加工技术 2010年第11期38卷 35-38页

作者：王小兵罗士烓何家金广东新合铝业有限公司广东佛山528226 广东坚美铝型材厂有限公司广东佛山528231

扼要介绍了铝型材的一种无铬电化学抛光生产工艺技术与设备。讨论了抛光液各组分对抛光质量的影响,提出了三步电压控制的电解抛光工艺技术与参数。实践证明,采用这种电解抛光工艺获得的产品质量优于传统含铬电化学抛光工艺获得的,具有... 详细信息

扼要介绍了铝型材的一种无铬电化学抛光生产工艺技术与设备。讨论了抛光液各组分对抛光质量的影响,提出了三步电压控制的电解抛光工艺技术与参数。实践证明,采用这种电解抛光工艺获得的产品质量优于传统含铬电化学抛光工艺获得的,具有较高的应用推广价值。

关键词：铝型材无铬电化学抛光三步电压控制工艺技术