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Ballistic impact response of resistance-spot-welded(RSW) double-layered plates for Q&P980 steel

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Defence Technology（防务技术） 2022年第6期18卷 1052-1064页

作者： Bo-han Ma Dong-fang Ma Huan-ran Wang da-nian chen Feng-hua Zhou MOE Key Laboratory of Impact and Safety Engineering Ningbo UniversityNingbo315211China College of Science&Technology Ningbo UniversityNingbo315211China

Ballistic impact response of resistance-spot-welded(RSW)double-layered(2×1.6 mm)plates(190 mm×150 mm)for Q&P980 steel impacted by a round-nosed steel bullet(12 mm diameter and 30 mm length)was investigated by using gas gun and high-speed camera *** RSW specimens were spot welded using a 6 mm diameter electrode face producing a 7.2 mm diameter fusion zone of the spot *** ballistic curve and energy balance for the tests of the spot weld of the RSW specimens at different velocity were analyzed to characterize the ballistic behavior of the RSW specimens under bullet *** fracture mechanisms of the RSW specimens under bullet impact were *** the tests below the ballistic limit,the cracks initiated from the notch-tip and propagated along the faying surface or obliquely through the thickness depending on the impact *** the tests above the ballistic limit,the plug fracture in the front plate of the RSW specimen could be caused by the thinning-induced necking in the BM near the HAZ,while the plug fracture in the rear plate of the RSW specimens may be consist of the circumferential cracking from the rear surface and the bending fracture of the hinged part of *** effects of the electrode indentation and the weld interfaces on deformation and fracture of the RSW specimens under bullet impact were *** the tests above the ballistic limit,the circumferential fracture from the rear surface of the RSW specimens was always initiated along the interior periphery of the electrode indentation and the crack paths were along the FZ/CGHAZ or CGHAZ/FGHAZ *** the circumferential crack also formed outside the electrode indentation,the fracture on the BM/HAZ interface could be *** the front plate of the RSW specimens,the shear/bending induced cracking from the notch-tip were observed and the crack paths were along the FZ/CGHAZ or CGHAZ/FGHAZ interface.

关键词： RSW Q&P980 steel Ballistic impact Deformation Fracture

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人不是物:社会认知的稽古维新

心理学报 2025年第1期57卷 173-189页

作者：董达陈巍绍兴文理学院心理学系大脑、心智与教育研究中心浙江绍兴312000 中国人民大学哲学与认知科学交叉平台北京100080

当代社会认知的理论版图可分为经典概念工具箱与正在与之对抗的新概念工具两部分。经考证,理论论和模拟论等经典概念工具集中诞生于1980年代的美国认知科学界,可以被视为1956认知革命蔓延至社会心理学领域的产物,而新概念工具可以被视... 详细信息

当代社会认知的理论版图可分为经典概念工具箱与正在与之对抗的新概念工具两部分。经考证,理论论和模拟论等经典概念工具集中诞生于1980年代的美国认知科学界,可以被视为1956认知革命蔓延至社会心理学领域的产物,而新概念工具可以被视为与第二代认知革命相适合的替代理论。历史上,社会心理学接受了认知主义的“物”的抽象认知原理,也全盘接受了它带来的理论负荷,即对“人”的感知被还原为对“物”的感知,并且隶属于后者。然而,基于“物”的抽象认知原理始终无法与社会认知的以“人”为本的实践经验相结合,也未能实现该领域的自治。事实上,这一理论困难并非一直存在于“社会认知”的历史路径中,至少在以Heider为标志性人物的1950年代早期社会认知中便不是这样。Heider“人不是物”理论体系在个体层面上包括知觉实在论、事件归因和生命性−非生命性范畴区分三个部分,但是第三个理论部件彼时囿于作者主题侧重、证据不足、技术匮乏等多种原因未能完成。结合当代来自演化和比较的、行为和发展的以及神经通路假设的新证据,通过重新发掘并最终完整构建了“人不是物”论题,尝试为当代社会认知理论困难提供一个建设性意见。

关键词：社会认知人的感知认知革命生命性主体间性

Observation of topological charge transformations in acoustic vortex using passive periodic systems

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 140-147页

作者： Di-Chao chen Xie Liu Changqing Xu da-Jian Wu Ying cheng Xiao-Jun Liu School of Physics and Technology Nanjing Normal University Key Laboratory of Modern Acoustics School of Physics Nanjing University

Vortex transmutation utilizes a periodic system, which not only enables the alteration of the topological charge(TC) of unstable input vortices but also facilitates their transformation into stable structures. This approach is crucial for investigating the characteristics of vortices in various wave systems. Here, we achieve acoustic vortex TC transmutation by employing a welldesigned dual-structured plate external system(DPES). The interactions between the acoustic vortex and the finite-order discrete rotational symmetry lead to the transformation of its topological charge when complete rotational symmetry is broken to Nthorder discrete symmetry. Our results experimentally demonstrate the acoustic vortex TC transmutation based on passive artificial structures, enabling numerous applications in particle manipulation and information multiplexing as well as advancing our understanding and control over free-space acoustic vortices.

关键词： acoustic vortex topological charge transformation artificial structure

3D Printing of Tough Hydrogel Scaffolds with Functional Surface Structures for Tissue Regeneration

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Nano-Micro Letters 2025年第2期17卷 18-45页

作者： Ke Yao Gaoying Hong Ximin Yuan Weicheng Kong Pengcheng Xia Yuanrong Li Yuewei chen nian Liu Jing He Jue Shi Zihe Hu Yanyan Zhou Zhijian Xie Yong He State Key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China Liangzhu Laboratory Zhejiang UniversityHangzhou 310027People’s Republic of China Key Laboratory of 3D Printing Process and Equipment of Zhejiang Province College of Mechanical EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China Stomatology Hospital School of StomatologyZhejiang University School of MedicineHangzhou 310027People’s Republic of China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001People’s Republic of China Institute of Digital Medicine Nanjing First HospitalNanjing Medical UniversityNanjing 210006People’s Republic of China

Hydrogel scaffolds have numerous potential applications in the tissue engineering ***,tough hydrogel scaffolds implanted in vivo are seldom reported because it is difficult to balance biocompatibility and high mechanical *** by Chinese ramen,we propose a universal fabricating method(printing-P,training-T,cross-linking-C,PTC&PCT)for tough hydrogel scaffolds to fill this ***,3D printing fabricates a hydrogel scaffold with desired structures(P).Then,the scaffold could have extraordinarily high mechanical properties and functional surface structure by cycle mechanical training with salting-out assistance(T).Finally,the training results are fixed by photo-cross-linking processing(C).The tough gelatin hydrogel scaffolds exhibit excellent tensile strength of 6.66 MPa(622-fold untreated)and have excellent ***,this scaffold possesses functional surface structures from nanometer to micron to millimeter,which can efficiently induce directional cell ***,this strategy can produce bionic human tissue with mechanical properties of 10 kPa-10 MPa by changing the type of salt,and many hydrogels,such as gelatin and silk,could be improved with PTC or PCT *** experiments show that this scaffold can effectively promote the new generation of muscle fibers,blood vessels,and nerves within 4 weeks,prompting the rapid regeneration of large-volume muscle loss injuries.

关键词： 3D printing Tough hydrogel scaffold Functional surface structure Tissue regeneration Biomaterials

Micro-strain regulation strategy to stabilize perovskite lattice based on the categories and impact of strain on perovskite solar cells

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Journal of Energy Chemistry 2025年第1期100卷 578-604页

作者： Caixia Li Wenwu Liu Shiji da Lingbin Kong Fen Ran State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of Technology School of Materials Science and Engineering Lanzhou University of Technology

Photovoltaic metal halide perovskite solar cells(PSCs) convert light to electricity more efficiently than crystalline silicon cells, and the cost of materials used to make them is lower than that of silicon *** efficiency is not a core issue affecting the application of perovskite solar cells in special *** present, stability is the major technical encounters that hinders its further commercial development. Microstrain in PSCs is currently a significant factor responsible for the device's instability. Strain-induced ion migration is widely believed to accelerate perovskite degradation even when external stimuli are ***, it is imperative to study strain to enhance the stability of PSCs. This paper reviews recent developments to understand strain's origin and effect mechanisms on performance of PSCs, including ion migration,failure behavior, defect formation, and its effect on photoelectric properties, stability, and ***, several well-known strain management strategies are systematically introduced based on the strain effect mechanism and strain engineering on the film, providing more clues for further preparation with increased stability. The manipulation of external physical strain applied from films to entire devices has been extensively studied. Furthermore, recommendations for future research directions and chemical approaches have been provided. It is emphasized that strain engineering plays a crucial role in improving the efficiency and longevity of PSCs. Tensile strain causes rapid degradation, while moderate compressive strain and external strain control could improve properties and stability. Efforts should focus on controlling compressive strain to mitigate residual tensile strain and introducing it in a controlled manner. Future research endeavors may focus on exploring these pathways to improve the efficiency and lifespan of PSCs.

关键词： Halide perovskite solar cells Strain origins Strain effects Strain management

Synergistic effect of bonding heterogeneity and phonon localization in introducing excellent thermoelectric properties in layered heteroanionic NdZnSbO material

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Journal of Energy Chemistry 2025年第1期100卷 259-272页

作者： da Wan Shuwei Tang Shulin Bai Xiaodong Li Peng Ai Wanrong Guo Tuo Zheng College of Materials Science and Engineering Liaoning Technical University Faculty of Chemistry Northeast Normal University

Layered rare-earth metal oxides, harnessing the dual properties of oxides and two-dimensional layered materials, exhibit remarkable thermal stability and quantum confinement effects. Therefore, this work adopts the first-principles calculation combined with the Boltzmann transport theory to predict the thermoelectric properties of NdZnSbO compound. The coexistence of weak interlayer van der Waals interactions, robust intralayer ionic bonding, and partial covalent bonding leads to remarkable bonding heterogeneity, which engenders pronounced phonon scattering and imposes constraints on thermal transport along the out-of-plane direction. The weakened chemical bonds induced by the antibonding states, together with the rattling-like behavior of the Zn atom, culminate in the profound anharmonicity in the layered NdZnSbO compound. The weakening bond and heavy element contribute to the softness of phonon modes, which significantly diminishes the phonon group velocity. The redistribution-dominated four-phonon scattering process spans a large optical gap, which effectively reduces the lattice thermal conductivity. The NdZnSbO compound exhibits direct semiconductor characteristic with a bandgap of 0.73 e V by adopting the Heyd-Scuseria-Ernzerhof(HSE06) functional in combination with spin–orbit coupling(SOC) effect. The multi-valley feature of NdZnSbO compound augur favorably for band degeneracy, thus amplifying the power factor. Consequently, an optimal figure-of-merit(ZT) of 3.40 at 900 K is achieved for the n-type NdZnSbO compound. The present study delves deeply insights into the origins for the low thermal conductivity of NdZnSbO compound and proposes an optimization scheme to enhance overall thermoelectric performance.

关键词： Bond strength (chemical)

骨质疏松性骨折人群跌倒风险、骨密度、肌力和体脂的相关性

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中华骨质疏松和骨矿盐疾病杂志 2017年第1期10卷 53-57页

作者：朱秀芬彭志坚 Brian Lin 马大年陈新杨海明林华南京大学医学院附属鼓楼医院骨病中心南京210008 昆山市中医院医务处昆山215300 Department of Neuroscience Johns Hopkins University3400N Baltimore 江苏省盱眙县人民医院骨科盱眙211700

目的探讨骨质疏松性骨折人群的骨密度与跌倒风险、体质量指数(body mass index,BMI)、肌力、体脂含量的相关性。方法通过对4 632例社区45岁以上绝经后女性的问卷调研及骨密度筛查,筛查出既往有脆性骨折史的骨质疏松性骨折人群。测定骨... 详细信息

目的探讨骨质疏松性骨折人群的骨密度与跌倒风险、体质量指数(body mass index,BMI)、肌力、体脂含量的相关性。方法通过对4 632例社区45岁以上绝经后女性的问卷调研及骨密度筛查,筛查出既往有脆性骨折史的骨质疏松性骨折人群。测定骨质疏松性骨折人群的骨密度、身高、体质量、跌倒风险、肌力和腹部脂肪含量。采用Spearman检验分析跌倒指数、体脂含量、年龄、身高、体质量、BMI与骨密度(bone mass density,BMD)之间的相关性。BMD校正年龄、身高、体质量、BMI、体脂含量,采用ANCOVA分析跌倒指数对BMD的影响;校正年龄、身高、体质量、BMI、跌倒指数,分析体脂含量对BMD的影响。结果对筛查出的839例骨质疏松性骨折患者的BMD、BMI、跌倒风险、腹部体脂含量、肌力等相关性分析结果显示,骨质疏松性骨折人群BMI、跌倒指数、肌力与BMD均显著相关(BMI r=0.161,跌倒指数r=0.238,肌力r=0.198,P均0.05)。结论跌倒风险和低BMD为骨折的主要危险因素。本研究显示体脂含量与BMD呈显著相关性。

关键词：骨质疏松性骨折骨密度肌力跌倒风险体脂含量

Role of the Greenland Sea ice anomaly in the late-spring drought over Northwest China

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Atmospheric and Oceanic Science Letters 2025年第1期18卷 1-5页

作者： Yang Liu Huopo chen Nansen-Zhu International Research Centre Institute of Atmospheric Physics Chinese Academy of SciencesBeijingChina Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Nanjing University for Information Science and TechnologyNanjingChina

Drought across Northwest China in late spring has exerted a vital effect on the local climate and agricultural production,and has been alleviated during the past *** study explored the influence of the preceding Arctic sea ice on the May drought in Northwest China caused by the precipitation *** analysis indicated that when the Greenland Sea ice concentration is abnormally high during February to April,the dry conditions in Northwest China tend to be *** increase of sea ice in the Greenland Sea can excite a meridional circulation,which causes sea surface temperature(SST)anomalies in the North Atlantic via the sea-air interaction,manifested as significant warm SST anomalies over the south of Greenland and the subtropical North Atlantic,but negative SST anomalies over the west of the *** abnormal SST pattern maintains to May and triggers a zonal wave train from the North Atlantic through Scandinavia and Central Asia to Northwest China,leading to abnormal cyclones in Northwest ***,Northwest China experiences a more humid climate than usual.

关键词： Arctic sea ice Greenland Sea North Atlantic SST Drought Northwest China

Cell polarization in ischemic stroke: molecular mechanisms and advances

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Neural Regeneration Research 2025年第3期20卷 632-645页

作者： Yuanwei Li Xiaoxiao Xu Xuan Wu Jiarui Li Shiling chen danyang chen Gaigai Li Zhouping Tang Department of Neurology Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanHubei ProvinceChina

Ischemic stroke is a cerebrovascular disease associated with high mortality and disability rates. Since the inflammation and immune response play a central role in driving ischemic damage, it becomes essential to modulate excessive inflammatory reactions to promote cell survival and facilitate tissue repair around the injury site. Various cell types are involved in the inflammatory response, including microglia, astrocytes, and neutrophils, each exhibiting distinct phenotypic profiles upon stimulation. They display either proinflammatory or anti-inflammatory states, a phenomenon known as ‘cell polarization.’ There are two cell polarization therapy strategies. The first involves inducing cells into a neuroprotective phenotype in vitro, then reintroducing them autologously. The second approach utilizes small molecular substances to directly affect cells in vivo. In this review, we elucidate the polarization dynamics of the three reactive cell populations(microglia, astrocytes, and neutrophils) in the context of ischemic stroke, and provide a comprehensive summary of the molecular mechanisms involved in their phenotypic switching. By unraveling the complexity of cell polarization, we hope to offer insights for future research on neuroinflammation and novel therapeutic strategies for ischemic stroke.

关键词： astrocyte polarization immune regulation inflammation ischemic injury microglia polarization neutrophil polarization signaling pathways stroke