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Rare Metals 2024年第9期43卷 4387-4400页

作者： Ao Xia Jia-Guang Zheng Qing-Bo zhang Yu-Gang Shu Cheng-Guo Yan liu-Ting zhang Zhan-Liang Tao Li-Xin Chen School of Energy and Power Jiangsu University of Science and Technology Key Laboratory of Advanced Energy Materials Chemistry(Ministry of Education) Nankai University State Key Laboratory of Silicon and Advanced Semiconductor Materials School of Materials Science and EngineeringZhejiang University

The facile construction of nanoscale NbHxsupported by Ti3C2（NbHx@Ti3C2） was achieved using facile ball milling strategy to improve the hydrogen desorption kinetics and reversibility of magnesium borohydride (Mg（BH4）2).The doping of 30 wt%NbHx@Ti3C2catalyst reduced the onset dehydrogenation temperature of Mg（BH4）2to 71.2℃.Additionally,the Mg（BH4）2+30NbHx@Ti3C2composite achieved remarkable hydrogen release of over 9.2 wt% at a temperature as low as 230℃,indicating unexpected dehydrogenation ***,the reversibility of NbHx@Ti3C2doped Mg（BH4）2was retained to more than 4.2 wt%after four cycles,which was increased by 68% compared to that of undoped Mg（BH4）*** strong catalysis of NbHx@Ti3C2catalyst could be attributed to the synergistic effect of NbHxand Ti3C2in hydrogen spillover and *** as a??hydrogen pump??for effective hydrogen spillover,while Ti3C2created numerous diffusion channels for hydrogen dissolution and provided the active catalytic site to facilitate the re/dehydrogenation of Mg（BH4）2.

关键词： Catalysts Hydrogen storage Magnesium borohydride Mxene

Signal space transform and multidimensional information joint processing for moving target

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Chinese Journal of Acoustics 2024年第1期43卷 23-48页

作者： SHI Yunjia PIAO Shengchun GUO Junyuan zhang liu Acoustic Science and Technology Laboratory Harbin Engineering UniversityHarbin 150001 Key Laboratory of Marine Information Acquisition and Security(Harbin Engineering University) Ministry of Industry and Information TechnologyHarbin 150001 College of Underwater Acoustic Engineering Harbin Engineering UniversityHarbin 150001

A signal space transform method for detection of line spectrum signals radiated by moving target is *** time-frequency analysis and beamforming processing,a three-dimensional(3D)time-frequency-azimuth signal space is obtained in the array coordinate *** certain target course angle,this 3D signal space is transformed to the time-frequency-relative bearing spectrum signal space in the target coordinate *** theoretical derivation,simulation,and experimental data processing are *** findings demonstrate that the method is capable of converting the target line spectrum signal 3D trajectory to a 2D trajectory on the corresponding slice in the transformed signal space and signal processing gain of multi-dimensional information joint processing is obtained easier than in 3D signal space.

关键词： system. moving transformed

Optimizing FeCoNiCrTi high-entropy alloy with hydrogen pumping effect to boost de/hydrogenation performance of magnesium hydride

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Rare Metals 2024年第7期43卷 3273-3285页

作者： Meng-Chen Song Fu-Ying Wu Yi-Qun Jiang Xiu-Zhen Wang Hu Zhao Li-Xin Chen liu-Ting zhang School of Energy and Power Instrumental Analysis CenterJiangsu University of Science and TechnologyZhenjiang 212003China Max Planck Institute for Iron Research 40237DuisseldorfGermany School of Mechanical and Aerospace Engineering Nanyang Technological UniversitySingapore 639798Singapore State Key Laboratory of Silicon Materials Department of Materials Science and EngineeringZhejiang UniversityHangzhou 310027China

The exploration of efficient,long-lived and cost-effective transition metal catalysts is highly desirable for the practical hydrogen storage of magnesium hydride(MgH_(2)) in sustainable energy ***,FeCoNiCrTi high-entropy alloy(HEA) nanosheets were prepared via a facile wet chemical ball milling strategy and they were introduced into MgH_(2) to boost the hydrogen storage *** refined HEA exhibited superior catalytic activity on MgH_(2).In contrast to additive-free MgH_(2),the initial desorption temperature of the constructed MgH_(2)-HEA composite was reduced from 330.0 to 198.5℃ and a remarkable 51% reduction in the dehydrogenation activation energy was ***,the MgH_(2)-HEA composite only required one-twentieth time of that consumed by pure MgH_(2) to absorb 5.0 wt% of H_(2) at 225℃.The synergy between the "hydrogen pumping" effect of Mg_2Ni/Mg_2NiH_4 and Mg_2Co/Mg_2CoH_5 couples,as well as the good dispersion of Fe,Cr and Ti on the surface of MgH_(2) contributed to the enhanced de/hydrogenation performance of the MgH_(2)-HEA *** study furnishes important steering for the design and fabrication of multiple transition metal catalysts and may push the commercial application of magnesium-based hydrides one step forward.

关键词： Hydrogen storage Magnesium hydride High-entropy alloys Catalysis

Influence of temperature, stress, and grain size on behavior of nano-polycrystalline niobium

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Chinese Physics B 2024年第7期33卷 467-474页

作者：晏玉平张柳亭张丽攀芦刚涂志新 School of Acronautical Manufacturing Engineering Nanchang Hangkong UniversityNanchang 330063China

Atomic simulations are executed to investigate the creep responses of nano-polycrystalline(NC) niobium established by using the Voronoi algorithm. The effects of varying temperature, applied stress, and grain size(GS) on creep properties and mechanisms are investigated. Notably, the occurrence of tertiary creep is exclusively observed under conditions where the applied stress exceeds 4.5 GPa and the temperature is higher than 1100 K. This phenomenon can be attributed to the significant acceleration of grain boundary and lattice diffusion, driven by the elevated temperature and stress levels. It is found that the strain rate increases with both temperature and stress increasing. However, an interesting trend is observed in which the strain rate decreases as the grain size increases. The stress and temperature are crucial parameters governing the creep behavior. As these factors intensify, the creep mechanism undergoes a sequential transformation: initially from lattice diffusion under low stress and temperature conditions to a mixed mode combining grain boundaries(GBs) and lattice diffusion at moderate stress and mid temperature levels, and ultimately leading to the failure of power-law controlled creep behavior, inclusive of grain boundary recrystallization under high stress and temperature conditions. This comprehensive analysis provides in more detail an understanding of the intricate creep behavior of nano-polycrystalline niobium and its dependence on various physical parameters.

关键词： creep behavior molecular dynamics simulation activation energy stress exponent nano-polycrystalline niobium

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基于等面积圆环和伴星夹角的星图识别算法

吉林大学学报（工学版） 2024年第3期54卷 821-827页

作者：张刘何金航刘赫章家保吕雪莹吉林大学仪器科学与电气工程学院长春130012

针对于传统径向和环向特征星图识别算法在构建径向特征过程中伴星分布不均匀以及采用环向特征匹配过程中特征值不稳定的问题,提出了一种等面积圆环划分和伴星矢量夹角相结合的星图识别算法。通过选取动态半径使得径向特征下的圆环面积相... 详细信息

针对于传统径向和环向特征星图识别算法在构建径向特征过程中伴星分布不均匀以及采用环向特征匹配过程中特征值不稳定的问题,提出了一种等面积圆环划分和伴星矢量夹角相结合的星图识别算法。通过选取动态半径使得径向特征下的圆环面积相等,保证伴星落在每个圆环的概率相等,有效提高了径向匹配过程的识别率。对于径向匹配后冗余的导航星,采用伴星组成的矢量夹角特征进行筛选,选定匹配特征值最高的为最终识别结果。仿真模拟结果表明:当添加位置噪声为1像素时,星图识别成功率达到95%;当伪星数目为2颗时,识别率达到98%。相较于传统径向和环向识别算法,本文方法在识别率和识别速度上具有明显优势。

关键词：星图识别径向特征环向特征匹配度

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清洁取暖政策试点的空气质量改善效应评估——基于三批试点地级市的准自然实验

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中国环境科学 2024年第1期44卷 581-592页

作者：王玉刘文璋中国人民大学公共管理学院北京100872 中国兵器工业集团人才研究中心北京100070

为评估清洁取暖试点政策的空气质量改善效果,基于2014~2019年321个地级行政单位6年的平衡面板数据,采用多期双重差分(DID)方法对清洁取暖试点政策效果进行定量评估.研究发现,清洁取暖试点政策显著降低了城市空气污染水平,改善了空气质量... 详细信息

为评估清洁取暖试点政策的空气质量改善效果,基于2014~2019年321个地级行政单位6年的平衡面板数据,采用多期双重差分(DID)方法对清洁取暖试点政策效果进行定量评估.研究发现,清洁取暖试点政策显著降低了城市空气污染水平,改善了空气质量,平均而言,试点城市的空气质量指数(AQI)比非试点城市显著低4.12;AQI,PM_(2.5),PM_(10)和SO_(2)分别下降了约5.49%,11.47%,12.65%和35.66%.这一结论在进行了一系列稳健性检验后依然成立.清洁取暖试点政策改善城市环境质量的内在机制在于,试点政策改变了城市居民采暖能源结构,减少了硫化物和颗粒物的排放.因此“十四五”期间应进一步扩大清洁取暖政策范围,增加财政投入,提高财政支出效率,降低清洁能源成本,推广清洁能源全覆盖.

关键词：清洁取暖空气质量政策评估能源结构 PM_(2.5) 多期双重差分(DID)

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基于仿生控冰材料的生物安全冷冻保存策略

石油化工 2024年第8期53卷 1205-1217页

作者：王凌琪刘樟王健君中国科学院理化技术研究所中国科学院大学

冷冻保存技术是维持细胞、组织和器官活性的重要手段，实现安全有效的冷冻保存会为生物科学和临床医学研究带来历史性的变革。传统的小分子冷冻保护剂（如二甲基亚砜（DMSO））在冷冻保存过程中发挥着重要作用，但它在分子、亚细胞、细... 详细信息

冷冻保存技术是维持细胞、组织和器官活性的重要手段，实现安全有效的冷冻保存会为生物科学和临床医学研究带来历史性的变革。传统的小分子冷冻保护剂（如二甲基亚砜（DMSO））在冷冻保存过程中发挥着重要作用，但它在分子、亚细胞、细胞以及组织器官和个体层面的结构破坏作用和生物毒性，使其在冷冻保存中的应用受到很大的局限。探讨并总结了DMSO的毒性以及当前研究者在冷冻保存领域中努力探索的新型控冰材料，特别是受自然界极端环境中耐寒生物的启发而创制的一系列具有良好生物相容性的仿生控冰材料，概述了控冰材料的发展历程，分析了仿生控冰材料等新型控冰材料在生物样本冷冻保存中的优势、挑战，并展望了未来的发展趋势。

关键词：冷冻保存二甲基亚砜生物相容性冰结合蛋白仿生控冰材料冷冻保护剂

Overall clinical course of indeterminate dendritic cell tumor patients without skin lesions:A rare case report

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World Journal of Clinical Cases 2024年第19期12卷 4022-4028页

作者： Hao Liang Yun-Fei Zhao liu-Ping zhang Ya-Kun Wu Department of Hepatobiliary Surgery Suining Central HospitalSuining 629000Sichuan ProvinceChina Department of Pathology Suining Central HospitalSuining 629000Sichuan ProvinceChina Department of Gastrointestinal Surgery Suining Central HospitalSuining 629000Sichuan ProvinceChina

BACKGROUND Indeterminate dendritic cell tumor(IDCT)is a rare tumor of immune cells,and IDCT patients without skin lesions are rarely ***,the clinical course in this type of patient is unclear,and further research on the underlying pathological mechanisms and appropriate treatments is *** SUMMARY This study describes a female IDCT patient with bile duct *** strong mimicry of IDCT lesions confused doctors,and consequently,this patient,who had no skin lesions,was first diagnosed with ***,she presented with persistent abdominal distension without *** mesenteric lymph nodes along with massive ascites were observed in the subsequent imaging ***,no tumor cells or pathogens were found in the three subsequent ascites *** took 2 years to reach the correct diagnosis,which was eventually obtained by performing surgery for biopsy of the patient’s abdominal lymph ***,by then,she was already in a cachexic ***,she received a cycle of cyclophosphamide therapy and was advised to visit a hospital specializing in rare *** For IDCT patients without skin lesions,early biopsy is the key to obtaining a correct ***,the collective management of IDCT patients is *** histological and molecular biology studies based on human specimens are critical for understanding the pathological mechanism of dendritic cell tumors in the future.

关键词： Indeterminate dendritic cell tumor Clinical development Surgical biopsy Collective management Dendritic cell Case report

The cardiovascular system at high altitude:A bibliometric and visualization analysis

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World Journal of Cardiology 2024年第4期16卷 199-214页

作者： Mao-Lin Zhao Zhong-Jie Lu Li Yang Sheng Ding Feng Gao Yuan-zhang liu Xue-Lin Yang Xia Li Si-Yi He Department of Cardiovascular Surgery The General Hospital of Western Theater CommandCollege of MedicineSouthwest Jiaotong UniversityChengdu 610083Sichuan ProvinceChina Department of Cardiovascular Surgery The General Hospital of Western Theater CommandChengdu 610083Sichuan ProvinceChina

BACKGROUND When exposed to high-altitude environments,the cardiovascular system undergoes various changes,the performance and mechanisms of which remain *** To summarize the latest research advancements and hot research points in the cardiovascular system at high altitude by conducting a bibliometric and visualization *** The literature was systematically retrieved and filtered using the Web of Science Core Collection of Science Citation Index Expanded.A visualization analysis of the identified publications was conducted employing CiteSpace and *** A total of 1674 publications were included in the study,with an observed annual increase in the number of publications spanning from 1990 to *** United States of America emerged as the predominant contributor,while Universidad Peruana Cayetano Heredia stood out as the institution with the highest publication ***,Jean-Paul Richalet demonstrated the highest productivity among researchers focusing on the cardiovascular system at high ***,Peter Bärtsch emerged as the author with the highest number of cited *** analysis identified hypoxia,exercise,acclimatization,acute and chronic mountain sickness,pulmonary hypertension,metabolism,and echocardiography as the primary research hot research points and emerging directions in the study of the cardiovascular system at high *** Over the past 32 years,research on the cardiovascular system in high-altitude regions has been steadily *** research in this field may focus on areas such as hypoxia adaptation,metabolism,and cardiopulmonary *** interdisciplinary and multi-team collaborations will facilitate further exploration of the pathophysiological mechanisms underlying cardiovascular changes in high-altitude environments and provide a theoretical basis for standardized disease diagnosis and treatment.

关键词： Cardiovascular system High altitude Hypoxia Bibliometric analysis Visualization

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中华鲟物种保护的若干问题探讨

水生生物学报 2024年第9期48卷 1603-1609页

作者：刘焕章中国科学院水生生物研究所武汉430072

中华鲟是国家一级保护动物,长江中的旗舰物种。IUCN在2009年就将其评估为极度濒危。2013年首次发现中华鲟没有野外繁殖。此后,虽然在2014和2016年有再次野外繁殖,但是自2017年以来,已经连续7年没有发现中华鲟野外繁殖,中华鲟已经面临野... 详细信息

中华鲟是国家一级保护动物,长江中的旗舰物种。IUCN在2009年就将其评估为极度濒危。2013年首次发现中华鲟没有野外繁殖。此后,虽然在2014和2016年有再次野外繁殖,但是自2017年以来,已经连续7年没有发现中华鲟野外繁殖,中华鲟已经面临野外灭绝的风险。应该采取什么样的措施进行中华鲟的保护,是当前各方面都非常关心的议题。有学者提出了要在葛洲坝和三峡水利枢纽修建鱼道,以及在三峡库区以上江段放流中华鲟的建议。这些建议是否合适?如何才能切实有效地保护中华鲟物种?其中的科学问题迫切需要厘清。作者的研究团队长期进行中华鲟的保护生物学研究,本文拟对我们团队的研究结果作一介绍,同时对大家关心的中华鲟保护工作中的一些问题进行讨论,期望能为中华鲟的保护工作提供参考。

关键词：中华鲟放流三峡水利枢纽物种保护鱼道极度濒危保护生物学研究三峡库区