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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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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

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Recent advances in exploring new blood-based biomarkers for the early diagnosis of gastric cancer

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Science China Chemistry 2025年第1期68卷 35-45页

作者： Xinyu Peng Qian Ma da Han School of Life Science Shanghai University Institute of Molecular Medicine Shanghai Key Laboratory for Nucleic Acid Chemistry and Nanomedicine State Key Laboratory of Oncogenes and Related Genes Renji Hospital School of Medicine Shanghai Jiao Tong University Department of Research and Development Intellinosis Biotechnologies Co.Ltd.

Gastric cancer(GC) is a prevalent and lethal malignancy worldwide, and the 5-year survival rate is less than 30%. The absence of distinctive symptoms often leads to late-stage diagnosis, contributing to a grim prognosis. Early detection is pivotal for improving the survival rates and outcomes of GC patients. Traditional diagnostic methods, including gastroscopy and histopathological examination, are restricted in the early diagnosis of GC. Conventional protein biomarkers, such as carcinoembryonic antigen(CEA), carbohydrate antigen 19-9(CA19-9), and carbohydrate antigen 72-4(CA72-4), exhibit insufficient sensitivity and specificity for GC screening, which diminishes their clinical value. Recently, novel circulating biomarkers, such as circulating tumor cells(CTCs), circulating tumor cell DNA(ct DNA), and circulating free RNA(cf RNA), have emerged as promising candidates in the burgeoning field of liquid biopsy due to their superior sensitivity and specificity. This review focuses on the latest research on blood-based biomarkers for GC diagnosis and examines the clinical potentials and challenges associated with these emerging biomarkers.

关键词： gastric cancer early diagnosis blood

Facile synthesis of the dodecahydridododecaborate (B12H122-) from borane Lewis base adducts

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Science China Chemistry 2025年

作者： Yi Jing Xin-Ran Liu Xing-Hua Wang Hui Han Sha-Sha Liang Xi-Meng chen Dong-Hui Wei Lai-Sheng Wang Xue-nian chen College of Chemistry Zhengzhou University School of Chemistry and Chemical Engineering Henan Key Laboratory of Boron Chemistry and Advanced MaterialsHenan Normal University Department of Chemistry Brown University

Polyhedral boranes are a class of well-known boron molecular clusters widely used in energy,chemistry,medicine,and materials science because of their unique physical and chemical *** efforts have been made in the past decades to find more effective synthetic methods for this important class of boron ***,existing synthetic methods suffer from low efficiency and low ***,we report a facile one-pot synthesis of[（CH3）3S]2B12H12with moderate yields at mild *** mechanisms for the multi-step chemoselective synthesis of B12H122-without other by-products are elucidated based on theoretical results and our previous *** Lewis base used in B–H bond condensation reaction,which acts as a hydrogen or to balance the newly generated polyhedral borane charges,is proposed and studied in *** current study has led to a more effective and selective synthetic method for B12H122-and has also implicated the syntheses of other new polyhedral boranes.

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Enhancing forecasting of current-carrying performance through spatial frequency analysis of interface morphology

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Science China Technological Sciences 2025年

作者： nian YIN Zishuai WU Zhangli HOU Yiwei ZHANG Zhinan ZHANG State Key Laboratory of Mechanical System and Vibration Shanghai Jiao Tong University School of Mechanical Engineering Shanghai Jiao Tong University

Electrical contact interfaces, integral to devices such as connectors, switches, and conductive slip rings, play a crucial role in determining current-carrying capabilities. This study adopts spatial frequency analysis to assess the currentcarrying performance of interfaces based on their morphological characteristics. Initially, rough surfaces with various parameters, including the cutoff frequency(N), the spectral index(β), and the gain factor(A), were generated using spatial frequency methods, followed by current-carrying simulations. The findings reveal that the characteristic parameters derived from spatial frequency methods exhibit a significantly stronger correlation with current-carrying performance than traditional roughness metrics. To enhance the practical applicability of this research, a physical-informed machine learning approach for rough surface features extraction was developed, demonstrating high predictive parameter identification accuracy for the three parameters. Overall, this paper introduces a tribo-informatics approach for analyzing and extracting rough surface features that considers the curvature characteristics of contact points. This approach holds significant potential for evaluating the processing state of current-carrying interfaces, selecting high-quality surfaces, and forecasting current-carrying performances.

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Halogen composition and heterogeneity in the continental lithospheric mantle

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Science China Earth Sciences 2025年第1期68卷 310-314页

作者： Chunfei chen State Key Laboratory of Geological Processes and Mineral Resources School of Earth Sciences China University of Geosciences

1. Introduction Halogens, including fluorine(F), chlorine(Cl), bromine(Br), and iodine(I), are highly mobile and water-soluble elements that can become significantly enriched in melts and fluids. In fluids and melts, halogens react with nearly all metals and readily form complexes with metal cations, significantly influencing the distribution of metal elements between different phases. Therefore, halogens play a crucial role in the migration, enrichment, and mineralization of key metals in the lithosphere(Weis et al., 2012; Liu et al., 2024).

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Cyano migration-mediated radical-polar crossover cyclopropanation

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Science China Chemistry 2025年第1期68卷 241-248页

作者： Ziqiang Wang Yasu chen Jie Li chen Zhu Key Laboratory of Organic Synthesis of Jiangsu Province College of Chemistry Chemical Engineering and Materials ScienceSoochow University Frontiers Science Center for Transformative Molecules Zhangjiang Institute for Advanced Study and Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs Shanghai Jiao Tong University

We report a novel cyano migration-mediated radical-polar crossover process, whereby both the sulfonylcyanation of aliphatic alkenes and the formation of cyclopropanes are concurrently achieved. This transformation yields a diverse array of multisubstituted cyclopropanes under mild photocatalytic conditions. Mechanistic studies elucidate that the reaction proceeds via intramolecular nucleophilic substitution, leading to the formation of the cyclopropane derivatives.

关键词： cyclopropanation cyano migration radical-polar crossover radical reactions

Oxygen vacancies enriched Ir/WOx catalysts for the directly chem-catalytic conversion of cellulose to ethanol

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Tungsten 2025年第1期7卷 88-99页

作者： Yu-Jing Weng Zhao-Ying Ding Ying-Chao Li Yuan-Feng Wu Yuan-Yang Xu Rui chen Xiao-Lei Zhao Hai-Yong Wang da-Lei Zhang Yu-Long Zhang Henan Key Laboratory of Coal Green Conversion and International Joint Laboratory of Coal Clean Utilization College of Chemistry and Chemical Engineering Henan Polytechnic University Key Laboratory of Renewable Energy Guangzhou Institute of Energy Conversion Chinese Academy of Sciences Liaoning Institute of Energy Technology

Tungsten and its oxides are highly versatile catalysts with unique properties that hold great promise for a wide array of applications,including biological pathways and chemical *** chemo-catalysis of cellulose to ethanol presents a promising avenue for ethanol synthesis with the potential for enhanced efficiency compared to conventional methods,offering a sustainable and carbon-neutral alternative to existing petrochemical and biological ***,Ir/WOxcatalysts enriched with oxygen vacancies were meticulously prepared and demonstrated remarkable catalytic performance in converting cellulose to ethanol directly in the presence of tungstic *** catalyst achieved a high ethanol yield of 66.5%under optimal reaction conditions,approaching the theoretical yield limit of traditional ethanol *** results revealed the presence of oxygen defects,Bronsted/Lewis acidity,and Ir nanoclusters on the catalyst surface,working synergistically to facilitate the cascade catalysis of cellulose hydrolysis,sugar retro-aldol condensation reaction,and C2 intermediate hydrodeoxygenation to *** situ Fourier transform infrared spectrometer analysis confirmed the catalyst's ability to enhance the adsorption and activation of ethylene glycol for ethanol *** manipulating subtle structural features,this study offers a fresh perspective on tungsten group catalyst design and underscores the importance of synergistic effects among catalytic sites for the efficient production of ethanol from cellulose.

关键词： Cellulosic ethanol Chem-catalysis Hydrogenolysis Retro-aldol condensation Tungsten