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Enzymatic self-assembly/disassembly turns “ON”/“OFF” the mimetic hydrolytic activity of histidine nanofibers

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Science China che.istry 2024年第2期67卷 517-522页

作者： Xianbao Sun Manli Wang Xiaoyang Liu Wenjun Zhan Guangqiong xu Qiaochu Jiang Hai-dong xu Fuqiang Wang Gaolin Liang State Key Laboratory of Digital Medical Engineering School of Biological Science and Medical EngineeringSoutheast UniversityNanjing210096China Analysis Center Nanjing Medical UniversityNanjing210029China

Mimetic enzymes are devised as alternates or supplements of natural enzymes in broad fields but regulating their activities in a switchable manner remains ***,we proposed an enzymatic self-assembly/disassembly strategy to address this issue.A peptide molecule Nap FFEYIH(YH) was rationally designed which,after self-assembling into nanofibers,lined up the histidine moieties to form active hydrolysis centers for mimicking hydrolase *** dephosphorylation of Nap FFEYp IH(Yp H) by alkaline phosphatase to yield YH also turned “ON” the hydrolase *** turn,phosphorylation of YH by phosphokinase epidermal growth factor receptor to yield Yp H disassembled the nanofibers and thus turned the activity “OFF”.As such,the “ON”/“OFF” of the mimetic hydrolase activities could be regulated under physiological conditions through ALP/EGFR-mediated self-assembly/disassembly of histidine *** work provides a feasible strategy for the on-demand fabrication of artificial enzymes with controllable and superior activities.

关键词： disassembly hydrolytic activity mimetic enzyme phosphorylation self-assembly

Divergent defluorocarboxylation of α-CF_(3) alkenes with formate via photocatalyzed selective mono-or triple C-F bond cleavage

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Science China che.istry 2024年第1期67卷 368-373页

作者： Xing-Yu Wang Pei xu Wen-Wen Liu Hao-Qiang Jiang Song-Lei Zhu dong Guo xu Zhu Jiangsu Key Laboratory of New Drug Research and Clinical Pharmacy School of PharmacyXuzhou Medical UniversityXuzhou 22100China

Unprecedented divergent synthesis of gem-difluorovinylacetic acid and glutaric acid derivatives fromα-CF_(3)alkenes with formate as the carbonyl source was *** reaction can undergo selective mono-or triple C-F bond cleavage by simply switching the photocatalyst and hydrogen atom transfer(HAT)catalyst under visible-light-induced conditions at room *** acts as both the C1 source and the reductant through the generation of CO_(2)^(·-)species,which underwent Giese radical addition to electron-deficient alkenes to trigger the consecutive C-F bond cleavage and carboxylation process.

关键词： C-F bond activation defluorocarboxylation carbon dioxide radical anion visible light

Ultrahard X-ray multifunctional application beamline at the SSRF

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Nuclear Science and Techniques 2024年第6期35卷 14-25页

作者： Ke Yang Zhao-Hui dong Chun-Yin Zhou Zi-Long Zhao dong-xu Liang Sai-Chao Cao Ai-Guo Li Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai 201210China

The ultrahard X-ray multifunctional application beamline(BL12SW)is a phase-II beamline project at the Shanghai Syn-chrotron Radiation *** primary X-ray techniques used at the beamline are high-energy X-ray diffraction and imaging using white and monochromatic *** main scientific objectives of ultrahard X-ray beamlines are focused on two research *** is the study of the structural properties of Earth’s interior and new materials under extreme high-temperature and high-pressure conditions,and the other is the characterization of materials and processes in near-real service *** beamline utilizes a superconducting wiggler as the light source,with two diamond windows and SiC discs to filter out low-energy light(primarily below 30 keV)and a Cu filter assembly to control the thermal load entering the subsequent optical *** beamline is equipped with dual *** first was a meridional bending Laue monochromator cooled by liquid nitrogen,achieving a full-energy coverage of 30-162 *** second was a sagittal bending Laue monochromator installed in an external building,providing a focused beam in the horizontal direction with an energy range of 60-120 *** were four experimental hutche.:two large-volume press experimental hutche.(LVP1 and LVP2)and two engineering material experimental hutche.(ENG1 and ENG2).Each hutch was equipped with various near-real service conditions to satisfy different *** example,LVP1 and LVP2 were equipped with a 200-ton DDIA press and a 2000-ton dual-mode(DDIA and Kawai)press,***1 and ENG2 provide in situ tensile,creep,and fatigue tests as well as high-temperature *** June 2023,the BL12SW has been in trial *** is expected to officially open to users by early 2024.

关键词： Shanghai Synchrotron Radiation Facility Ultrahard X-ray High energy diffraction High energy imaging Engineering materials Earth science

Efficient concentration of trace analyte with ordered hotspot construction for a robust and sensitive SERS platform

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International Journal of Extreme Manufacturing 2024年第3期6卷 532-542页

作者： Youdi Hu Yanlei Hu Zhenyu Wang Jiale Yong Wei Xiong dong Wu Shixiang xu Shenzhen Key Laboratory of Micro-Nano Photonic Information Technology College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhenGuangdong 518060People’s Republic of China CAS Key Laboratory of Mechanical Behavior and Design of Materials Key Laboratory of Precision Scientific Instrumentation of Anhui Higher Education InstitutesDepartment of Precision Machinery and Precision InstrumentationUniversity of Science and Technology of ChinaHefeiAnhui 230027People’s Republic of China Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhanHubeiPeople’s Republic of China

Surface-enhanced Raman scattering(SERS)platform,which enables trace analyte detection,has important application *** structuring/modifying the surface of the SERSsubstrate,analyte in highly diluted solutions can be concentrated into localized active areas for highly sensitive ***,subject to the difficulty of the fabrication process,itremains challenging to balance hot-spot construction and the concentration capacity of analyte ***,preparing SERS substrates with densely ordered hot spots andefficient concentration capacity is of great significance for highly sensitive ***,we propose an Ag and fluoroalkyl-modified hierarchical armour substrate(Ag/F-HA),which has a double-layer stacking design to combine analyte concentration with hotspot *** microarmour structure is fabricated by femtosecond-laser processing to serve as asuperhydrophobic and low-adhesive surface to concentrate analyte,while the anodic aluminium oxide(AAO)template creates a nanopillar array serving as dense and ordered hot *** the synergistic action of hot spots and analyte concentration,Ag/F-HA achieves a detectionlimit down to 10^(-7)M doxorubicin(DOX)molecules with a RSD of 7.69%.Additionally,Ag/F-HA exhibits excellent robustness to resist external disturbances such as liquid splash or *** on our strategy,SERS substrates with directional analyte concentrations are further explored by patterning microcone arrays with *** work opens a way to the realistic implementation of SERS in diverse scenarios.

关键词： surface-enhanced Raman scattering anodic aluminium oxide femtosecond laser processing concentration of trace analytes mechanical robustness

Photo-induced tunable luminescence from an aggregated amphiphilic ethylene-pyrene derivative in aqueous media

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Chinese che.ical Letters 2024年第6期35卷 303-306页

作者： Junying Zhang Ruoche. Li Haihua Wang Wenbing Kang Xing-dong xu National Engineering Research Center for Colloidal Materials Key Laboratory of Special Functional Aggregated Materials of Ministry of EducationShandong Key Laboratory of Advanced Silicone Materials and TechnologySchool of Chemistry and Chemical EngineeringShandong UniversityJi’nan 250100China

An amphiphilic derivative with a large Stokes shift by introducing flexible hydrophilic long chains into a rigid ethylene-pyrene compound have been successfully *** alkylated compound exhibited a notable change in charge distribution,facilitating cation-π *** the process of amphiphilic self-assembly,the formation of highly ordered aggregates enabled effective photo-dimerization under 449 nm LED ***,this photo-responsive technology not only exhibited advanced multi-color emission effects,including white light emission but also exhibited environmentally friendly behavior in the aqueous phase.

关键词： Supramolecular che.istry Amphiphilic assembly Stimuli-responsive materials Tunable luminescence Pyrene derivative

Classification and rating of disintegrated dolomite strata for slope stability analysis

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第7期16卷 2552-2562页

作者： Wenlian Liu Xinyue Gong Jiaxing dong Hanhua xu Peixuan Dai Shengwei Zhang Kunming Prospecting Design Institute of China Nonferrous Metals Industry Co. Ltd.Kunming650051China Key Laboratory of Geotechnical Engineering and Geological Disasters of Yunnan Province Kunming650051China Faculty of Electric Power Engineering Kunming University of Science and TechnologyKunming650500China

Although disintegrated dolomite,widely distributed across the globe,has conventionally been a focus of research in underground engineering,the issue of slope stability issues in disintegrated dolomite strata is gaining increasing *** is primarily due to their unique properties,including low strength and loose *** methods for evaluating slope stability,such as basic quality(BQ)and slope stability probability classification(SSPC),do not adequately account for the poor integrity and structural fragmentation characteristic of disintegrated *** address this challenge,an analysis of the applicability of the limit equilibrium method(LEM),BQ,and SSPC methods was conducted on eight disintegrated dolomite slopes located in Baoshan,Southwest ***,conflicting results were ***,this paper introduces a novel method,SMRDDS,to provide rapid and accurate assessment of disintegrated dolomite slope *** method incorporates parameters such as disintegrated grade,joint state,groundwater conditions,and excavation *** findings reveal that six slopes exhibit stability,while two are considered partially ***,the proposed method demonstrates a closer match with the actual conditions and is more time-efficient compared with the BQ and SSPC ***,due to the limited research on disintegrated dolomite slopes,the results of the SMRDDS method tend to be conservative as a safety *** conclusion,the SMRDDS method can quickly evaluate the current situation of disintegrated dolomite slopes in the *** contributes significantly to disaster risk reduction for disintegrated dolomite slopes.

关键词： Disintegrated dolomite slope Basic quality(BQ) Slope stability probability classification (SSPC) Rock mass quality classification Limit equilibrium method(LEM)

Intelligent representation method of image flatness for cold rolled strip

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Journal of Iron and Steel Research International 2024年第5期31卷 1177-1195页

作者： Yang-huan xu dong-che.g Wang Hong-min Liu Bo-wei Duan National Engineering Research Center for Equipment and Technology of Cold Strip Rolling Yanshan UniversityQinhuangdao066004HebeiChina National Key Laboratory of Metal Forming Technology and Heavy Equipment China National Heavy Machinery Research Institute Co.Ltd.Xi’an710018ShaanxiChina State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao066004HebeiChina

Real flatness images are the bases for flatness detection based on machine vision of cold rolled *** characteristics of a real flatness image are analyzed,and a lightweight strip location detection(SLD)model with deep semantic segmentation networks is *** interference areas in the real flatness image can be eliminated by the SLD model,and valid information can be *** this basis,the concept of image flatness is proposed for the first *** image flatness representation(IFAR)model is established on the basis of an autoencoder with a new *** optimal structure of the bottleneck layer is 16×16×4,and the IFAR model exhibits a good representation ***,interpretability analysis of the representation factors is carried out,and the difference and physical meaning of the representation factors for image flatness with different categories are *** flatness with new defect morphologies(bilateral quarter waves and large middle waves)that are not present in the original dataset are generated by modifying the representation factors of the no wave ***,the SLD and IFAR models are used to detect and represent all the real flatness images on the test *** average processing time for a single image is 11.42 ms,which is suitable for industrial *** research results provide effective methods and ideas for intelligent flatness detection technology based on machine vision.

关键词： Cold rolled strip Image flatness Location detection Representation learning Bottleneck layer

A Self-sensing TSA-actuated Anthropomorphic Robot Hand

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Journal of Bionic Engineering 2024年第3期21卷 1174-1190页

作者： Chanchan xu Shuai dong Yifan Ma Jingwei Zhan Yuche.g Wang Xiaojie Wang Institute of Intelligent Machines Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei230031China CAS Key Laboratory of Mechanical Behavior and Design of Materials Department of Precision Machinery and Precision InstrumentationUniversity of Science and Technology of ChinaHefei230026China Institutes of Physical Science and Information Technology Anhui UniversityHefei230601China

This paper introduces a self-sensing anthropomorphic robot hand driven by Twisted String Actuators(TSAs).The use of TSAs provides several advantages such as muscle-like structures,high transmission ratios,large output forces,high efficiency,compactness,inherent compliance,and the ability to transmit power over ***,conventional sensors used in TSA-actuated robotic hands increase stiffness,mass,volume,and complexity,making feedback control *** address this issue,a novel self-sensing approach is proposed using strain-sensing string based on Conductive Polymer Composite(CPC).By measuring the resistance changes in the strain-sensing string,the bending angle of the robot hand's fingers can be estimated,enabling closed-loop control without external *** developed self-sensing anthropomorphic robot hand comprises a 3D-printed structure with five fingers,a palm,five self-sensing TSAs,and a 3D-printed *** studies validate the self-sensing properties of the TSA and the anthropomorphic robot ***,a real-time Virtual Reality(VR)monitoring system is implemented for visualizing and monitoring the robot hand's movements using its self-sensing *** research contributes valuable insights and advancements to the field of intelligent prosthetics and robotic end grippers.

关键词： Anthropomorphic robot hand Twisted string actuator Self-sensing Conductive polymer composite Virtual reality monitoring

Improving fatigue properties of normal direction ultrasonic vibration assisted face grinding Inconel 718 by regulating machined surface integrity

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International Journal of Extreme Manufacturing 2024年第3期6卷 458-475页

作者： Nianwei xu Renke Kang Bi Zhang Yuan Zhang che.xu Wang Yan Bao Zhigang dong State Key Laboratory of High-Performance Precision Manufacturing Dalian University of TechnologyDalian 116024People’s Republic of China Department of Mechanical and Energy Engineering Southern University of Science and TechnologyShenzhen 518055People’s Republic of China

Fatigue properties are crucial for critical aero-engine components in extreme serviceenvironments,which are significantly affected by surface integrity(SI)indexes(especially surface topography,residual stressσ_(res),and microhardness)after machining ***-direction ultrasonic vibration-assisted face grinding(ND-UVAFG)has advantages in improving the machinability of Inconel 718,but there is a competitive relationship between higher compressiveσ_(res)and higher surface roughness R_(a)in affecting fatigue *** lack of a quantitative relationship between multiple SI indexes and fatigue strength makes theindeterminacy of a regulatory strategy for improving fatigue *** this work,a model of fatigue strength(σ_f)_(sur)considering multiple SI indexes was ***,high-cycle fatigue tests were carried out on Inconel 718 samples with different SI characteristics,and the influence of ND-UVAFG process parameters on SI was *** on SI indexes data,the(σ_f)_(sur)distribution in the grinding surface layer for ND-UVAFG Inconel 718 samples was determined using the developed model,and then the fatigue crack initiation(FCI)sites were *** predicted FCI sites corresponded well with the experimental results,therebyverifying this model.A strategy for improving the fatigue life was proposed in this work,which was to transfer the fatigue source from the machined surface to the bulk material by controlling the SI ***,a critical condition of SI indexes that FCI sites appeared on the surface or in bulk material was given by fitting the predicted *** to the critical condition,an SI field where FCI sites appeared in the bulk material could be *** this field,thefatigue life of Inconel 718 samples could be improved by approximately 140%.

关键词： surface integrity fatigue strength Inconel 718 ultrasonic assisted grinding