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De novo synthesis of atropisomeric benzofurans via Cu/SPDO complex catalyzed asymmetric formal [3 + 2] annulation

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Science China Chemistry 2025年第1期68卷 174-180页

作者： fan-xiao Meng Xing-Yu Wang Ka Lu Ju-Song Yang Fu-Min Zhang Ai-Jun ma Bao Du Yong-Qiang Tu State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University School of Chemistry and Chemical Engineering Shanghai Jiao Tong University School of Biotechnology and Health Sciences Wuyi University

Herein, the de novo synthesis of atropisomeric benzofurans through the Cu/spirocyclic-pyrrolidine-oxazoline(SPDO) complex catalyze asymmetric formal [3 + 2] cycloaddition between quinones and ynamides is explored, producing a range of structurally diverse axially chiral benzofurans in satisfactory yields with good to excellent enantioselectivities. Furthermore, density functional theory calculations were applied to explain the possible reaction mechanism.

关键词： benzofuran atropisomers novel de novo synthetic strategy asymmetric formal [3 + 2] cycladdition Cu/SPDO complex DFT calculations

Influence of insulin resistance on long-term outcomes in patients with coronary artery disease after sirolimus-eluting stent implantation

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Chinese Medical Journal 2010年第6期123卷 651-657页

作者： ZHAO Liang-ping LU An-kang SHEN Wei-feng LIU Hai-feng ma xiao-ye fan xiao-ming ZHANG Qi Department of Cardiology Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghai 200025China

Background Insulin resistance（IR）is significantly associated with coronary artery disease and cardiovascular events in patients with or without type 2 diabetes *** study aimed to evaluate the influence of IR on long-term outcomes of patients undergoing percutaneous coronary intervention（PCI）with sirolimus-eluting stent（SES）*** A total of 467 consecutive patients undergoing SES-based PCI were divided into lR group（n=104）and non-IR group（n=363）.The patients were followed up for one *** rate of major adverse cardiac events（maCEs） including death, non-fatal myocardial infarction and recurrent angina pectoris was compared by the log-rank test,and the independent risk factors were identified by the Cox regression *** maCEs occurred more frequently,and cumulative survival rate was lower in the IR group than in the non-IR group during the follow-up （all P〈0.05）.IR was an independent risk factor for the occurrence of cardiac death and non-fatal myocardial infarction（OR=2176,95% CI=1.35-5.47,P=0.034）.Old age,diabetes,and multi-vessel disease were determinants for recurrent angina pectoris after PCI（P〈0.05）.Subgroup analysis revealed that IR（OR=3.35,95% CI=1.07-13.59,P=0.013）and multi-vessel disease（OR=2.19,95%CI=1.01-5.14,P=0.044）were independent risk predictors for recurrent angina pectoris in patients with diabetes after *** IR is associated with reduced maCE-free survival and remains an independent predictor for recurrent angina pectoris after PCI with SES implantation.

关键词： insulin resistance coronary artery disease sirolimus-eluting stent long-term prognosis

Compressive and tensile strength of polymer-based fiber composite sand

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Journal of Central South University 2022年第2期29卷 528-545页

作者： ma Ke LIU Jin JIANG Can-hui ma xiao-fan HUANG Lan-hua HE Cheng-zong QI Chang-qing School of Earth Sciences and Engineering Hohai UniversityNanjing 210098China Fujian Yongfu Electric Power Design Co.Ltd. Fuzhou 350108China

Traditional soil additives like Portland cement and lime are prone to cause the brittle fracture behavior of soil,and possibly,environmental *** study explores the potential use of polyurethane organic polymer and sisal fiber in improving the mechanical performance of *** effects of polymer content,fiber content,and dry density on the unconfined compressive strength(UCS)and direct tensile strength(DTS)of the polymer-fiber-sand composite were *** results showed significant increase in UCS and DTS of the reinforced sand with the increase of polymer content,fiber content,and dry *** high dry density condition,a single peaked stress−strain curve is often *** polymer content is beneficial to increasing the peak stress,while higher fiber content contributes more to the post-peak *** combined use of polymers and fibers in soil reinforcement effectively prevents the propagation and development of cracks under the *** electron microscopy(SEM)test was also performed to investigate the micro-structural changes and inter-particle *** was found through SEM images that the surface coating,bonding,and filling effects conferred by polymer matrix greatly enhance the interfacial interactions,and hence provide a cohesive environment where the strength of fibers could be readily mobilized.

关键词： sand soil reinforcement sisal fiber polyurethane organic polymer compressive strength tensile strength

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Unmasking Social Robots’Camouflage:A GNN-Random Forest Framework for Enhanced Detection

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Computers, materials & Continua 2025年第1期82卷 467-483页

作者： Weijian fan Chunhua Wang xiao Han Chichen Lin School of Data Science and Intelligent Media Communication University of ChinaBeijing100024China School of Computer and Cyber Sciences Communication University of ChinaBeijing100024China Institute of Communication Studies Communication University of ChinaBeijing100024China State Key Laboratory of Media Convergence and Communication Communication University of ChinaBeijing100024China

The proliferation of robot accounts on social media platforms has posed a significant negative impact,necessitating robust measures to counter network anomalies and safeguard content *** robot detection has emerged as a pivotal yet intricate task,aimed at mitigating the dissemination of misleading *** graphbased approaches have attained remarkable performance in this realm,they grapple with a fundamental limitation:the homogeneity assumption in graph convolution allows social robots to stealthily evade detection by mingling with genuine human *** unravel this challenge and thwart the camouflage tactics,this work proposed an innovative social robot detection framework based on enhanced HOmogeneity and Random Forest(HORFBot).At the core of HORFBot lies a homogeneous graph enhancement strategy,intricately woven with edge-removal techniques,tometiculously dissect the graph intomultiple revealing ***,leveraging the power of contrastive learning,the proposed methodology meticulously trains multiple graph convolutional networks,each honed to discern nuances within these tailored *** culminating stage involves the fusion of these feature-rich base classifiers,harmoniously aggregating their insights to produce a comprehensive detection *** experiments on three social robot detection datasets have shown that this method effectively improves the accuracy of social robot detection and outperforms comparative methods.

关键词： Social robot detection graph neural networks random forest homophily heterophily

Experimental Study on Geometry Characteristics of Turbulent Premixed Flames for Natural Gas/Air Mixtures

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Journal of Thermal Science 2025年第1期34卷 268-282页

作者： ZHENG Weilin WANG Qijiao xiao Huahua CHEN xiaoxiao XIE fan ZENG Wen Liaoning Key Lab of Advanced Test Technology for Aerospace Propulsion System Shenyang Aerospace University State Key Laboratory of Fire Science University of science and Technology of China AVIC Shenyang Aircraft Design and Research Institute

In this study,focusing on the geometry characteristics of spherical expanding flame,the turbulent premixed flames of natural gas/air mixtures were investigated in a fan-stirred turbulent *** effects of initial temperature（T=300-400 K）,initial pressure（P=0.1-0.3 MPa）,turbulence intensity（u'=1.0-2.7 m/s）,oxygen volumetric percentage(φ（O2）=15%-21%) and carbon dioxide volumetric percentage(φ（CO2）=0-20%)were delved *** flame profile under the Cartesian coordinate system was derived from the schlieren images taken by the high-speed ***,from both macroscopic and microscopic perspectives,the influence of experimental conditions on the flame geometry characteristics was explored through flame front extraction,wavelet decomposition and network *** results demonstrate that for significant flame wrinkling,changes in species concentrations and turbulence intensity have more pronounced effects on the flame wrinkling *** wrinkling of the flame front maintains a certain degree of similarity,as evidenced by the locally concentrated distribution of the angles of the maximum fluctuation *** disturbance energy under large-scale（D6-D8） disturbances exhibits relatively high values with a similar trend,exerting a significant impact on the geometry characteristics of the flame *** peaks of correlation degree are scattered either with the decomposition scale or the development of flame radius,indicating no linear correlation between different detail ***,the probability distribution of node degrees in key wrinkled regions exhibits different trends with that of large-scale wrinkling and disturbance energy,especially with changes in initial *** occurs because the number of key wrinkles varies based on the perturbation's strength or the region's ***,an increase in the fluctuation frequency of the flame's local radius may not necessarily lead to an increase in the number of key folded regions.

关键词： fan-stirred turbulent combustor geometry characteristics large-scale wrinkling network topology wavelet decomposition

Water-induced changes in strength characteristics of polyurethane polymer and polypropylene fiber reinforced sand

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Journal of Central South University 2021年第6期28卷 1829-1842页

作者： WANG Ying LIU Jin SHAO Yong ma xiao-fan QI Chang-qing CHEN Zhi-hao School of Earth Sciences and Engineering Hohai UniversityNanjing 210098China Jiangsu Taihu Lake Control Engineering Construction Administration Department of Water Resources of Jiangsu ProvinceWuxi 214000China

As a new kind of air-hardening soil reinforcement material,polymer is being widely applied in river-bank slope reinforcement and ecological slope protection ***,more attention should be paid to study the characteristics of reinforced soil after *** this study,water-induced changes in strength characteristics of sand reinforced with polymer and fibers were *** factors,including polymer content(1%,2%,3%and 4%by weight of dry sand),immersion time(6,12,24 and 48 h),dry density(1.40,1.45,1.50,1.55 and 1.60 g/cm^(3),)and fiber content(0.2%,0.4%,0.6%and 0.8%by weight of dry sand)which may influence the strength characteristics of reinforced sand after immersion were *** microstructure of reinforced sand was analyzed with nuclear magnetic resonance(NMR)and scanning electron microscope(SEM).Experimental results indicate that the compressive strength increases with the increase of polymer content and decreases with the increase of immersion time;the softening coefficients decrease with the increase of the polymer content and immersion time and increase with an increment in density and fiber *** plays an active role in reducing water-induced loss of strength at 0.6%content.

关键词： polymer fiber reinforced sand immersion compressive strength softening coefficient

维普期刊数据库

COMPrompter: reconceptualized segment anything model with multiprompt network for camouflaged object detection

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Science China(Information Sciences) 2025年第1期68卷 189-203页

作者： xiaoqin ZHANG Zhenni YU Li ZHAO Deng-Ping fan Guobao xiao Zhejiang Province Key Laboratory of Intelligent Informatics for Safety and Emergency Wenzhou University Nankai International Advanced Research Institute (SHENZHEN FUTIAN) College of Computer Science Nankai University School of Computer Science and Technology Tongji University

We rethink the segment anything model(SAM) and propose a novel multiprompt network called COMPrompter for camouflaged object detection(COD). SAM has zero-shot generalization ability beyond other models and can provide an ideal framework for COD. Our network aims to enhance the single prompt strategy in SAM to a multiprompt strategy. To achieve this, we propose an edge gradient extraction module, which generates a mask containing gradient information regarding the boundaries of camouflaged objects. This gradient mask is then used as a novel boundary prompt, enhancing the segmentation process. Thereafter, we design a box-boundary mutual guidance module, which fosters more precise and comprehensive feature extraction via mutual guidance between a boundary prompt and a box prompt. This collaboration enhances the model's ability to accurately detect camouflaged objects. Moreover, we employ the discrete wavelet transform to extract high-frequency features from image embeddings. The high-frequency features serve as a supplementary component to the multiprompt ***, our COMPrompter guides the network to achieve enhanced segmentation results, thereby advancing the development of SAM in terms of COD. Experimental results across COD benchmarks demonstrate that COMPrompter achieves a cutting-edge performance, surpassing the current leading model by an average positive metric of 2.2% in COD10K. In the specific application of COD, the experimental results in polyp segmentation show that our model is superior to top-tier methods as well. The code will be made available at https://***/guobaoxiao/COMPrompter.

关键词： segment anything model camouflaged object detection boundary prompt

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Bandgap characteristics analysis and graded design of a novel metamaterial for flexural wave suppression

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Applied mathematics and Mechanics(English Edition) 2025年第1期46卷 1-24页

作者： fan YANG Zhaoyang ma Xingming GUO Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai Institute of Applied Mathematics and Mechanics School of Mechanics and Engineering ScienceShanghai University Shanghai Institute of Aircraft Mechanics and Control

A novel elastic metamaterial is proposed with the aim of achieving lowfrequency broad bandgaps and bandgap regulation. The band structure of the proposed metamaterial is calculated based on the Floquet-Bloch theorem, and the boundary modes of each bandgap are analyzed to understand the effects of each component of the unit cell on the bandgap formation. It is found that the metamaterials with a low elastic modulus of ligaments can generate flexural wave bandgaps below 300 Hz. Multi-frequency vibrations can be suppressed through the selective manipulation of bandgaps. The dual-graded design of metamaterials that can significantly improve the bandgap width is proposed based on parametric studies. A new way that can regulate the bandgap is revealed by studying the graded elastic modulus in the substrate. The results demonstrate that the nonlinear gradient of the elastic modulus in the substrate offers better bandgap performance. Based on these analyses, the proposed elastic metamaterials can pave the way for multi-frequency vibration control, low-frequency bandgap broadening, and bandgap tuning.

关键词： Vibration analysis

Physics based circuit compatible model for hybrid antiferroelectric random access memory

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Science China(Information Sciences) 2025年第1期68卷 396-397页

作者： Qiuxia WU Yue PENG Wenwu xiao Wenxuan ma Shuo ZHANG Litao SUN Chunfu ZHANG xiaohua ma Yue HAO School of Microelectronics Xidian University Xi'an Uni IC Semiconductors

Since the discovery of HfO2-based ferroelectric （FE） materials in 2011,considerable advancements have been made in material preparation,mechanism research,and device realization [1].Consequently,these materials are now regarded as leading candidates for embedded non-volatile memory（eNVM）.Beyond eNVM applications,recent studies have demonstrated that memory devices with antiferroelectric（AFE） films can achieve high response speeds,low latency,and reduced power consumption while maintaining excellent endurance characteristics [2,3].Additionally,the typical double hysteresis loops and multiple non-overlapping polarization current peaks of AFE films offer a novel approach to designing multistate ***,in order to further promote the application of high storage density AFE,an AFRAM electronic design automation （EDA） model must be developed,and it has yet to be proposed.

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