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Dynamical switchable quantum nonreciprocity induced by off-resonant chiral two-photon driving

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 31-37页

作者： Da-Wei Liu Zi-Hao Li Shi-lei chao Ying wu Liu-Gang Si School of Physics and Institute for Quantum Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China

Optical nonreciprocity,which refers to the direction-dependent emission,scattering and absorption of photons,plays a very important role in quantum engineering and quantum information ***,we propose an all-optical approach to achieve the optical dynamical switchable quantum nonreciprocity by an off-resonant chiral two-photon driving in a single microring cavity,which differs from the conventional nonreciprocal *** is shown that the optical field with time-dependent statistical properties can be generated and the nonreciprocity flips periodically,with switchable photon blockade and photon-induced tunneling *** find that the dynamical system is robust and immune to the parameter variations,which loosens the parameter range of ***,the time window for one-way quantum information is sufficiently wide and *** work opens a new idea for the current quantum nonreciprocal research,which can facilitate a memory functionality and be used for future inmemory superconducting quantum *** other nonreciprocal quantum devices,i.e.,dynamical switchable nonreciprocal squeezing and entanglement,may be inspired by our method,which is expected to have important applications in future quantum technology.

关键词： dynamical switchable nonreciprocity single-photon source chiral two-photon driving

Adverse effect of niobium and boron on hot deformation behavior of sulfur-containing steel

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Journal of Iron and Steel Research International 2024年第1期31卷 252-263页

作者： Guo-ning He Shi-qi Wan Bo Jiang chao-lei Zhang Ya-zheng Liu Chun-jing wu School of Materials Science and Engineering University of Science and Technology BeijingBeijing100083China Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing100083China

The hot deformation behaviors of sulfur-containing gear steel 20MnCr5 containing three different contents of Nb and B(0,0.021%Nb,and 0.024%Nb-0.0022%B)were *** compression and tenssion tests were carried out by Gleeble3800 at the austenite region from 850 to 1150℃and the adverse effects of Nb and B were analyzed by the fracture,microstructure and precipitate *** compression tests showed that the proportions of instable area in hot processing maps of 0.021%Nb and Nb-B steels were higher and the deformability of Nb free steel was *** tensile deformation experiments showed that the reduction areas of Nb free,0.021%Nb and Nb-B steels were 92%-99%,84%-98%and 67%-97%,*** addition of Nb or Nb and B inhibited the dynamic recrystallization during hot deformation,and consequently,more deformed grains were then formed in 0.021%Nb and Nb-B steels thus to obtain the microstructure with worse uniformity and then deteriorate the *** addition,the interaction between inclusions and microalloyed elements was also *** particles of 0.021%Nb and Nb-B steels dynamically precipitated during deformation and precipitated together with MnS thus to worsen the deformability,resulting in the decrease of reduction area.

关键词： Hot deformation Gear steel Processing map Dynamic recrystallization Microalloying

Terminal-selective C（sp3）–H borylation of unbranched alkanes enabled by intermolecular radical sampling and LMCT photocatalysis

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National Science Review 2024年第5期11卷 96-98页

作者： Zhexuan lei Jie wu Department of Chemistry National University of Singapore

The selective functionalization of C（sp3）–H bonds with subtle differences in alkanes is highly sought after due to its atom-and step-efficiency. The activation of C（sp3）–H bonds through hydrogen atom transfer （HAT） has been extensively exploited to produce a valueadded product from unfunctionalized material [1,2].

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Intelligent feedforward gust alleviation based on neural network

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Chinese Journal of Aeronautics 2024年第3期37卷 116-132页

作者： Yitao ZHOU Zhigang wu chao YANG School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China

This paper proposes a neural network-based intelligent feedforward gust alleviation framework,which includes a neural network identification model and a neural network controller.A neural network training dataset is formed by collecting flight data and the gust data encountered during the aircraft flight.A neural network identification model is first trained to accurately predict the aircraft’s ***,based on the output of the identification model and the collected flight data,the parameters of the time-delay neural network controller are obtained through a learning *** simulation results show that the designed intelligent controller has good gust alleviation effects for both continuous turbulence excitation and discrete gust *** example,when the aircraft is 40000 kg and the flight speed is 0.81Ma,the controller achieves a 67.82%reduction in wingtip acceleration and a 35.90%reduction in center of mass acceleration under continuous turbulence *** considering the measurement uncertainties,such as noise existing in the collected data,the trained controller can still achieve an acceptable gust alleviation ***,considering a flight in which the aircraft mass is constantly changing,the intelligent controller,which continuously learns from new flight data,maintains a good gust alleviation effect throughout the flight.

关键词： Gust alleviation Intelligent control Feedforward control Neural networks Time-varying aircraft

Nonlinear aeroelastic analysis of a twin-tail boom UAV with rudder freeplay nonlinearities

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Chinese Journal of Aeronautics 2024年第9期37卷 276-296页

作者： Liuyue BAI Zhigang wu chao YANG School of Aeronautic Science and Engineering Beihang UniversityBeijing 10019lChina

The issue of nonlinear structural freeplays in aircraft has always been a significant *** study investigates the aeroelastic characteristics of a twin-tail boom Unmanned Aerial Vehicle(UAV)with simultaneous freeplay nonlinearity in its left and right rudders.A comprehen-sive Limit Cycle Oscillation(LCO)solution route is proposed for complex aircraft with multiple freeplays,which can consider both accuracy and *** the first time,this study reveals the unique LCO characteristics exhibited by twin-tail boom UAVs with rudder freeplays and pro-vides simulations and explanations of interesting phenomena observed during actual *** governing equations are established using the free-interface component mode synthesis method,and the LCOs of the system are mainly solved through the improved time-domain numerical con-tinuation method and frequency-domain numerical continuation ***,the study investigates the influence of the left and right rudder freeplay size ratio on the LCO *** results demonstrate that the twin-tail boom UAV exhibits two stable LCO types:close and dif-fering left and right rudder *** proposed method successfully describes the complete LCO behaviors of the ***,this study makes significant contributions to our understand-ing of the aeroelastic behavior of twin-tail boom UAVs with rudder freeplays.

关键词： Aeroelasticity Freeplay nonlinearity Limit cycle oscillation Numerical continuation Component mode synthesis

Active flutter suppression of nonlinear fin-actuator system via inverse system and immersion and invariance method

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Chinese Journal of Aeronautics 2024年第4期37卷 343-362页

作者： Jin LU Zhigang wu chao YANG Chinese Aeronautical Establishment Beijing 100029China School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China

Structural nonlinearities such as freeplay will affect the stability and even flight safety of the fin-actuator *** is a lack of a practical method for designing Active Flutter Suppression (AFS) control laws for nonlinear fin-actuator systems.A design method for the AFS controller of the nonlinear all-movable fin-electromechanical actuator system is established by combining the inverse system and the Immersion and Invariance (I&I) ***,the composite control law combining the inverse system principle and internal model control is used to offset the nonlinearity and dynamics of the actuator,so that its driving torque can follow the ideal ***,the ideal torque of the actuator is designed employing the I&I *** unfavorable oscillation of the fin is suppressed by making the output torque of the actuator track the ideal *** simulation results reveal that the proposed AFS method can increase the flutter speed of the nonlinear finactuator system with freeplay,and a set of controller parameters is also applicable for wider freeplay within a certain *** power required for the actuator does not exceed the power that can be provided by the commonly used aviation *** method can also resist a certain level of noise and external disturbance.

关键词： Aeroelasticity Active flutter suppression Fin-actuator system Freeplay Inverse system Immersion and invariance

Chemoselective and Living/Controlled Polymerization of Alkenyl Methacrylates by the Phosphonium Ylide/Organoaluminum Lewis Pairs

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Chinese Journal of Polymer Science 2024年第2期42卷 159-167,I0005页

作者： Zhi-Kang Chen wu-chao Zhao Yi-Ling Zhao Cong-lei Liu Liu-Yin Jiang Yue-Tao Zhang Hong-Ping Zhu State Key Laboratory of Physical Chemistry of Solid Surfaces College of Chemistry and Chemical EngineeringXiamen UniversityXiamen361005China State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun130012China

Chemoselective,living/controlled polymerizations of allyl methacrylate(AMA) and vinyl methacrylate(VMA) with/without methyl methacrylate(MMA) by using the phosphonium ylide/organoaluminum based Lewis pairs(LPs) have been *** P-ylide-2/AIMe(BHT)_(2)(Pylide-2=Ph_(3)P=CHMe and BHT=2,6-iBu_(2)-4-MeC_(6)H_(2)O) was demonstrated to be superior by which homopolymers PAMAs(M_(n)=27.6-111.5kg/mol and ■=1.14-1.25) and PVMAs(M_(n)=28.4-78.4 kg/mol and ■=1.12-1.18) and block copolymers PMMA-b-PAMA,PAMA-b-PVMA,PAMA-bPMMA,PMMA-b-PAMA-b-PMMA,PAMA-b-PMMA-b-PAMA,and PAMA-b-PVMA-b-PAMA were *** the polymerizations,all of the monomers were reacted by the conjugated ester vinyl groups leaving intactly the nonconjugated acryloxy *** pendant acryloxy groups attached to the main chain enable further to post-functionalization by the AIBN-induced radical "thiol-ene" reaction using PhCH_(2)*** thiolether side group-containing polymers PAMA-SCH_(2)Ph and PAMA-SCH_(2)Ph-b-PMMA-b-PAMA-SCH_(2)Ph were thus prepared.

关键词： Phosphonium ylide Alkenyl methacrylate Chemoselectivity Living/controlled polymerization Post-functionalization

Rapid Antidepressant-Like Potential of Chaihu Shugan San Depends on Suppressing Glutamate Neurotransmission and Activating Synaptic Proteins in Hippocampus of Female Mice

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Chinese Journal of Integrative Medicine 2024年第8期30卷 692-700页

作者： LU chao GAO Zi-wei XING Shan WANG Hui-hui HUANG Yun-ke ZHOU Hang wu lei Department of Chinese Medicine Preparations Affiliated Hospital of Nanjing University of Chinese MedicineJiangsu Province Hospital of Chinese MedicineNanjing210029China College of Chinese Medicine Nanjing University of Chinese MedicineNanjing210046China Department of Chinese Medicine Women’s HospitalSchool of MedicineZhejiang UniversityHangzhou310000China

Objective To explore the rapid antidepressant potential and the underlying mechanism of Chaihu Shugan San(CSS)in female *** Liquid chromatography mass spectrometry(LC-MS)/MS was used to determine the content of main components in CSS to determine its *** C57BL/6J mice were randomly divided into 4 groups,including control(saline),vehicle(saline),CSS(4 g/kg)and ketamine(30 mg/kg)*** were subjected to irregular stress stimulation for 4 weeks to establish the chronic mild stress(CMS)model,then received a single administration of *** hours later,the behavioral tests were performed,including open field test,tail suspension test(TST),forced swimming test(FST),novelty suppression feeding test(NSF),and sucrose preference test(SPT).Western blot analysis was used to detect the expression levels of N-methyl-D-aspartate receptor(NMDA)subtypes[N-methyl-D-aspartate receptor 1(NR1),NR2A,NR2B],synaptic proteins[synapsin1 and post synaptic density protein 95(PSD95)],and brain-derived neurotrophic factor(BDNF).Moreover,the rapid antidepressant effect of CSS was tested by pharmacological technologies and optogenetic interventions that activated glutamate receptors,*** Compared with the vehicle group,a single administration of CSS(4 g/kg)reversed all behavioral defects in TST,FST,SPT and NSF caused by CMS(P<0.05 or P<0.01).CSS also significantly decreased the expressions of NMDA subtypes(NR1,NR2A,NR2B)at 2 h in hippocampus of mice(all P<0.01).In addition,similar to ketamine,CSS increased levels of synaptic proteins and BDNF(P<0.05 or P<0.01).Furthermore,the rapid antidepressant effects of CSS were blocked by transient activation of NMDA receptors in the hippocampus(all P<0.01).Conclusion Rapid antidepressant effects of CSS by improving behavioral deficits in female CMS mice depended on rapid suppression of NMDA receptors and activation of synaptic proteins.

关键词： Chaihu Shugan San female rapid antidepressant potential N-methyl-D-aspartate receptor synapticprotein optogenetic Chinesemedicine

Martensitic transformation pathways and crystallographic orientation relationships in steel

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Journal of Materials Science & Technology 2024年第7期174卷 74-84页

作者： Tian-Wei Liu Xiao-lei wu State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100049China

Martensite is one of the most important structures determining the ability to tailor the performance of steel and several other engineering *** previous studies,the face-centered cubic(FCC)to hexag-onal close-packed(HCP)(or body-centered cubic(BCC))martensitic transformation and the FCC to body-centered tetragonal(BCT)(or BCC)martensitic transformation during deformation and quenching were widely investigated;these transformations usually improve the plasticity and strength of steel,*** this work,detailed transmission electron microscopy(TEM)observations and electron diffraction pattern analyses of the BCT and BCC twins are performed along the[110],[131],and[¯153]zone *** transformation of BCT twins into BCC twins along the[131]zone axis is also analyzed through in situ heating during the TEM *** high-resolution TEM observations of mutually perpendicular BCT variants are consistent with the atomic arrangement obtained for the quenching pathway during the martensitic *** addition,different orientation relationships between austenite and marten-site are explained in terms of the atomic migration occurring during the deformation pathway and the quenching pathway of the martensitic transformation.

关键词： Body-centered tetragonal twin Martensitic transformation Steel Transmission electron microscopy Orientation relationship