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Synthesis and characterization of iron clusters with an icosahedral [Fe@Fe12]16+ Core

National Science Review 2024年第4期11卷 123-129页

作者： Gan xu yun-Shu Cui xue-Lian Jiang Cong-qiao xu Jun Li xu-Dong Chen Jiangsu Collaborative Innovation Center of Biomedical Functional Materials and Jiangsu Key Laboratory of New Power Batteries School of Chemistry and Materials Science Nanjing Normal University Department of Chemistry and Guangdong Provincial Key Laboratory of Catalytic Chemistry Southern University of Science and Technology Department of Chemistry and Engineering Research Center of Advanced Rare-Earth Materials of Ministry of Education Tsinghua University State Key Laboratory of Coordination Chemistry Nanjing University

Iron-metal clusters are crucial in a variety of critical biological and material systems,including metalloenzymes,catalysts,and magnetic storage devices.However,a synthetic high-nuclear iron cluster has been absent due to the extreme difficulty in stabilizing species with direct iron-iron bonding.In this work,we have synthesized,crystallized,and characterized a（Tp*）4W4S12(Fe@Fe12) cluster(Tp*=tris（3,5-dimethyl-1-pyrazolyl）borate（1-）),which features a rare trideca-nuclear,icosahedral[Fe@Fe12] cluster core with direct multicenter iron-iron bonding between the interstitial iron（Fei） and peripheral irons（Fep）,as well as Fep…Fepferromagnetic coupling.Quantum chemistry studies reveal that the stability of the cluster arises from the 18-electron shell-closing of the [Fe@Fe12]16+core,assisted by its bonding interactions with the peripheral tridentate [（Tp*）WS3]4-ligands which possess both S→Fe donation and spin-polarized Fe-Wσ bonds.The ground-state electron spin is theoretically predicted to be S=32/2 for the cluster.The existence of low oxidation-state（OS～+1.23） iron in this compound may find interesting applications in magnetic storage,spintronics,redox chemistry,and cluster catalysis.

关键词： Fe13 cluster iron-sulfur cluster low-valence iron iron−iron bond high spin complex

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Enhancing the Interaction of Carbon Nanotubes by Metal-Organic Decomposition with Improved Mechanical Strength and Ultra-Broadband EMI Shielding Performance

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Nano-Micro Letters 2024年第7期16卷 281-294页

作者： Yu-Ying Shi Si-Yuan Liao qiao-Feng Wang Xin-yun xu Xiao-yun Wang Xin-Yin Gu You-Gen Hu Peng-Li Zhu Rong Sun Yan-Jun Wan Shenzhen Institute of Advanced Electronic Materials Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen 518055People’s Republic of China Southern University of Science and Technology Shenzhen 518055People’s Republic of China National Key Laboratory of Materials for Integrated Circuits Shanghai Institute of Microsystem and Information TechnologyChinese Academy of SciencesShanghai 200050People’s Republic of China

The remarkable properties of carbon nanotubes(CNTs)have led to promising applications in the field of electromagnetic inter-ference(EMI)shielding.However,for macroscopic CNT assemblies,such as CNT film,achieving high electrical and mechanical properties remains challenging,which heavily depends on the tube-tube interac-tions of CNTs.Herein,we develop a novel strategy based on metal-organic decomposition(MOD)to fabricate a flexible silver-carbon nanotube(Ag-CNT)film.The Ag particles are introduced in situ into the CNT film through annealing of MOD,leading to enhanced tube-tube interactions.As a result,the electrical conductivity of Ag-CNT film is up to 6.82×10^(5) S m^(-1),and the EMI shielding effectiveness of Ag-CNT film with a thickness of~7.8μm exceeds 66 dB in the ultra-broad frequency range(3-40 GHz).The tensile strength and Young’s modulus of Ag-CNT film increase from 30.09±3.14 to 76.06±6.20 MPa(~253%)and from 1.12±0.33 to 8.90±0.97 GPa(~795%),respectively.Moreover,the Ag-CNT film exhibits excellent near-field shield-ing performance,which can effectively block wireless transmission.This innovative approach provides an effective route to further apply macroscopic CNT assemblies to future portable and wearable electronic devices.

关键词： EMI shielding Mechanical strength Carbon nanotubes Metal-organic decomposition Flexibility

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Millimeter-wave PA design techniques in ISSCC 2024

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Journal of Semiconductors 2024年第4期45卷 16-18页

作者： yun Wang Hongtao xu State Key Laboratory of Integrated Chips and Systems School of MicroelectronicsFudan UniversityShanghai 201203China

Millimeter-wave systems with high integration level have been rapidly developed to enable modern wireless communication,sensing,and imaging.The millimeter-wave power amplifier(PA)is one of the most challenging and critical components in a millimeter-wave transceiver,it is the last active stage in a transmitter amplifying spectrally efficient complex modulation signal for radiation with high output power.

关键词： millimeter Millimeter ISSCC

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Towards robustness and generalization of point cloud representation:A geometry coding method and a large-scale object-level dataset

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Computational Visual Media 2024年第1期10卷 27-43页

作者： Mingye xu Zhipeng Zhou Yali Wang Yu qiao Guangdong-Hong Kong-Macao Joint Laboratory of Human-Machine Intelligence-Synergy Systems Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen518000China University of Chinese Academy of Sciences Beijing065001China Shanghai AI Laboratory Shanghai200001China SIAT Branch Shenzhen Institute of Artificial Intelligence and Robotics for SocietyShenzhen518000China Alibaba DAMO Academy Hangzhou242332China

Robustness and generalization are two challenging problems for learning point cloud representation.To tackle these problems,we first design a novel geometry coding model,which can effectively use an invariant eigengraph to group points with similar geometric information,even when such points are far from each other.We also introduce a large-scale point cloud dataset,PCNet184.It consists of 184 categories and 51,915 synthetic objects,which brings new challenges for point cloud classification,and provides a new benchmark to assess point cloud cross-domain generalization.Finally,we perform extensive experiments on point cloud classification,using ModelNet40,ScanObjectNN,and our PCNet184,and segmentation,using ShapeNetPart and S3DIS.Our method achieves comparable performance to state-of-the-art methods on these datasets,for both supervised and unsupervised learning.Code and our dataset are available at https://***/Mingyexu/PCNet184.

关键词： geometry coding self-supervised learning point cloud classification segmentation 3D analysis

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Identifying the geographical origin and processing technology of Moyao(Myrrh) on the basis of near-infrared spectroscopy combined with chemometrics

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Journal of Traditional Chinese Medicine 2024年第3期44卷 505-514页

作者： xu Ningning YAN Ganming xu Fengjie DENG Linfeng qiao Xinjiang LU Changzheng CHENG Shaomin TCM Diagnosis Institute College of Traditional Chinese MedicineJiangxi University of Chinese Medicine TCM Processing Institute Pharmaceutical CollegeJiangxi University of Chinese medicine School of Electronic Information and Artificial Intelligence Shaanxi University of Science and Technology Jiangzhong Pharmaceutical Co. Ltd. Jiangxi Guhan Refined Chinese Herbal Pieces Co. Ltd.

OBJECTIVE: To evaluate the quality of Moyao(Myrrh) in the identification of the geographical origin and processing of the products. METHODS: Raw Moyao(Myrrh) and two kinds of Moyao(Myrrh) processed with vinegar from three countries were identified using near-infrared(NIR) spectroscopy combined with chemometric techniques. Principal component analysis(PCA) was used to reduce the dimensionality of the data and visualize the clustering of samples from different categories. A classical chemometric algorithm(PLS-DA) and two machine learning algorithms [K-nearest neighbor(KNN) and support vector machine] were used to conduct a classification analysis of the near-infrared spectra of the Moyao(Myrrh) samples, and their discriminative performance was evaluated. RESULTS: Based on the accuracy, precision, recall rate, and F1 value in each model, the results showed that the classical chemometric algorithm and the machine learning algorithm obtained positive results. In all of the chemometric analyses, the NIR spectrum of Moyao(Myrrh) preprocessed by standard normal variation or Multivariate scattering correction combined with KNN achieved the highest accuracy in identifying the geographical origins, and the accuracy of identifying the processing technology established by the KNN method after first-order derivative pretreatment was the best. The best accuracy of geographical origin discrimination and processing technology discrimination were 0.9853 and 0.9706 respectively. CONCLUSIONS: NIR spectroscopy combined with chemometric technology can be an important tool for tracking the origin and processing technology of Moyao(Myrrh) and can also provide a reference for evaluations of its quality and the clinical use.

关键词： Moyao () geographical origin near-infrared spectroscopy processing technology

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Screening and identification of functional bacterial attachment genes in aerobic granular sludge

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Journal of Environmental Sciences 2024年第7期141卷 205-214页

作者： Kai qiao Tingting Zhao LeiWang Wei Zhang WeiMeng Fan Liu xu Gao Jianrong Zhu School of Environment Beijing Normal UniversityBeijing 100875China State Key Laboratory of Water Simulation Beijing 100875China R&D Centre of Aerobic Granule Technology Beijing 100875China

The screening and identification of attachment genes is important to exploring the formation mechanism of biofilms at the gene level.It is helpful to the development of key culture technologies for aerobic granular sludge(AGS).In this study,genome-wide sequencing and gene editing were employed for the first time to investigate the effects and functions of attachment genes in AGS.With the help of whole-genome analysis,ten attachment genes were screened from thirteen genes,and the efficiency of gene screening was greatly improved.Then,two attachment genes were selected as examples to further confirm the gene functions by constructing gene-knockout recombinant mutants of Stenotrophomonas maltophilia;when the two attachment genes were knocked out,the attachment potential was reduced by 50.67%and 43.93%,respectively.The results provide a new theoretical principle and efficient method for the development of AGS from the perspective of attachment genes.

关键词： Attachment gene Genome-wide sequence Gene-knockout Attachment potential Aerobic granular sludge biofilm

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Mechanical Performance of Bio-inspired Bidirectional Corrugated Sandwich Pressure Shell Under External Hydrostatic Pressure

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China Ocean Engineering 2024年第2期38卷 297-312页

作者： ZHANG Yi CHEN Yue yun Lai LIANG xu Ocean College Zhejiang UniversityZhoushan 316000China Hainan Institute Zhejiang UniversitySanya 572000China

This paper aims to enhance the compression capacity of underwater cylindrical shells by adopting the corrugated sandwich structure of cuttlebone.The cuttlebone suffers uniaxial external compression,while underwater cylindrical shells are in a biaxial compressive stress state.To suit the biaxial compressive stress state,a novel bidirectional corrugated sandwich structure is proposed to improve the bearing capacity of cylindrical shells.The static and buckling analysis for the sandwich shell and the unstiffened cylindrical shell with the same volume-weight ratio are studied by numerical simulation.It is indicated that the proposed sandwich shell can effectively reduce the ratio between circumferential and axial stress from 2 to 1.25 and improve the critical buckling load by about 1.63 times.Numerical simulation shows that optimizing and adjusting the structural parameters could significantly improve the advantage of the sandwich shell.Then,the hydrostatic pressure tests for shell models fabricated by 3D printing are carried out.According to the experimental results,the overall failure position of the sandwich shell is at the center part of the sandwich shell.It has been found the average critical load of the proposed sandwich shell models exceeds two times that of the unstiffened shell models.Hence,the proposed bio-inspired bidirectional corrugated sandwich structure can significantly enhance the pressure resistance capability of cylindrical shells.

关键词： bio-inspiration bidirectional corrugation sandwich shell external pressure buckling

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The Application of Artificial Intelligence in Alzheimer’s Research

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Tsinghua Science and Technology 2024年第1期29卷 13-33页

作者： Qing Zhao Hanrui xu Jianqiang Li Faheem Akhtar Rajput Liyan qiao Faculty of Information Technology Beijing University of TechnologyBeijing 100124China School of Medicine Tsinghua UniversityBeijing 100084China Department of Computer Science Sukkur IBA UniversitySukkur 65200Pakistan Department of Neurology Tsinghua University Yuquan HospitalBeijing 100040China

Alzheimer's disease(AD)is an irreversible and neurodegenerative disease that slowly impairs memory and neurocognitive function,but the etiology of AD is still unclear.With the explosive growth of electronic health data,the application of artificial inteligence(Al)in the healthcare setting provides excellent potential for exploring etiology and personalized treatment approaches,and improving the disease's diagnostic and prognostic outcome.This paper first briefly introduces Al technologies and applications in medicine,and then presents a comprehensive review of Al in AD.In simple,it includes etiology discovery based on genetic data,computer-aided diagnosis(CAD),computer-aided prognosis(CAP)of AD using multi-modality data(genetic,neuroimaging and linguistic data),and pharmacological or non-pharmacological approaches for treating AD.Later,some popular publicly available AD datasets are introduced,which are important for advancing Al technologies in AD analysis.Finally,core research challenges and future research directions are discussed.

关键词： Alzheimer's disease artificial intelligence etiology discovery computer-aided diagnosis computer-aided prognosis treatment

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New insights into the effects of APP gene dose on synapse in Down syndrome

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Neural Regeneration Research 2024年第5期19卷 961-962页

作者： xu-qiao Chen Xinxin Zuo Department of Neurosciences University of California San DiegoLa JollaCAUSA

Synaptic dysfunction:Alzheimer’s disease(AD)is a prevalent form of dementia,affecting over 35 million people worldwide(Tzioras et al.,2023).A synapse serves as the connection point between neurons,facilitating the transmission of information from one neuron to another.Dynamic alterations in synapses,known as synaptic plasticity,play a pivotal role in cognitive processes such as learning and memory.Synaptic loss has been identified as a key contributor to cognitive decline in AD patients.Studies have shown that the soluble forms of amyloid-beta(Aβ)and tau proteins are toxic to synapses,leading to cognitive impairment in animal models(Spires-Jones and Hyman,2014).Additionally,the formation of oligomers of tau and Aβcan spread pathology through synaptic connections in the brain,emphasizing the vital role of synapses in disease progression.

关键词： alterations Aβ tau

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Gut-targeted therapies for type 2 diabetes mellitus: A review

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World Journal of Clinical Cases 2024年第1期12卷 1-8页

作者： Tian-Cheng xu yun Liu Zhi Yu Bin xu Key Laboratory of Acupuncture and Medicine Research of Ministry of Education Nanjing University of Chinese MedicineNanjing 210023Jiangsu ProvinceChina

Type 2 diabetes mellitus(T2DM)is a chronic metabolic disorder characterized by hyperglycemia and insulin resistance.The global prevalence of T2DM has reached epidemic proportions,affecting approximately 463 million adults worldwide in 2019.Current treatments for T2DM include lifestyle modifications,oral antidiabetic agents,and insulin therapy.However,these therapies may carry side effects and fail to achieve optimal glycemic control in some patients.Therefore,there is a growing interest in the role of gut microbiota and more gut-targeted therapies in the management of T2DM.The gut microbiota,which refers to the community of microorganisms that inhabit the human gut,has been shown to play a crucial role in the regulation of glucose metabolism and insulin sensitivity.Alterations in gut microbiota composition and diversity have been observed in T2DM patients,with a reduction in beneficial bacteria and an increase in pathogenic bacteria.This dysbiosis may contribute to the pathogenesis of the disease by promoting inflammation and impairing gut barrier function.Several gut-targeted therapies have been developed to modulate the gut microbiota and improve glycemic control in T2DM.One potential approach is the use of probio-tics,which are live microorganisms that confer health benefits to the host when administered in adequate amounts.Several randomized controlled trials have demonstrated that certain probiotics,such as Lactobacillus and Bifidobacterium species,can improve glycemic control and insulin sensitivity in T2DM patients.Mechanisms may include the production of short-chain fatty acids,the improvement of gut barrier function,and the reduction of inflammation.Another gut-targeted therapy is fecal microbiota transplantation(FMT),which involves the transfer of fecal material from a healthy donor to a recipient.FMT has been used successfully in the treatment of Clostridioides difficile infection and is now being investigated as a potential therapy for T2DM.A recent randomized controlled trial showed that FMT from lea

关键词： Type 2 diabetes mellitus Gastroenterology Bacteria Implanted device

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