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Vision-based docking system for an aromatic-hydrocarbon-inspired reconfigurable robot

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Science China(Technological Sciences) 2024年第6期67卷 1798-1816页

作者： xing FangYi XU Cheng LIU JinGuo xue ZhiHui State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang110016China School of Automation and Electrical Engineering Shenyang Ligong UniversityShenyang110158China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang110169China University of Chinese Academy of Sciences Beijing100049China

Aromatic hydrocarbons generally refer to compounds containing benzene *** types of isomers can be formed by replacing hydrogen atoms on the benzene *** this paper,an aromatic-hydrocarbon-inspired modular robot(AHIMR)is *** robot can be reassembled into different configurations suitable for various task requirements.A vision-based docking system is designed for the *** system primarily consists of two stages:a remote guidance stage and a precise docking *** the remote guidance stage,an object module is identified using an illumination adaptive target recognition algorithm,and then the active module moves to the docking area through communication with *** the precise docking stage,the active module calculates the relative pose with the object module using a perspective-n-point method and dynamically adjusts its posture to *** this process,a Kalman filter is used to reduce target occlusion and jitter *** addition,the docking system feasibility is verified via several simulation *** module docking accuracy is controlled within 0.01 m,which meets the reconfiguration task requirements of the *** the AHIMR submodule docking experiment,the active module accurately moves to the expected position with a docking success rate of 95%.

关键词： modular robot reconfiguration aromatic hydrocarbon autonomous docking visual identification

Rhodium-Catalyzed N-Arylation Addition of Arylboronic Acids to Ketimines

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Chinese Journal of Chemistry 2024年第18期42卷 2243-2248页

作者： xue-Wei Qian xing-Wen Sun Department of Chemistry Fudan University220 Handan RoadShanghai 200433China

Herein,we report rhodium catalyzed N-arylation via addition of arylboronic acids to electron-deficientα-iminoesters which can be prepared in high efficiency by using easily accessible B-carbonyl *** reaction is highly regiospecific to achieve the N-aryl addition efficiently with up to 99%yield under mild *** corresponding product can be further efficiently converted into indoles andaseries of other important building blocks.

关键词： Rhodium catalyzed N-Arylation addition Amines Umpolung Indole C-C coupling

Exploring multiple phases and first-order phase transitions in Kármán Vortex Street

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Science China(Physics,Mechanics & Astronomy) 2024年第11期67卷 47-54页

作者： Xu Li xing Xiang Tingting xue Limin Wang Xiaosong Chen School of Systems Science and Institute of Nonequilibrium Systems Beijing Normal UniversityBeijing 100875China State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy ofSciencesBeijing 100190China School of Chemical Engineering University of Chinese Academy of SciencesBeijing 100049China

Kármán Vortex Street, a fascinating phenomenon of fluid dynamics, has intrigued the scientific community for a long time. Many researchers have dedicated their efforts to unraveling the essence of this intriguing flow pattern. Here, we apply the lattice Boltzmann method with curved boundary conditions to simulate flows around a circular cylinder and study the emergence of Kármán Vortex Street using the eigen microstate approach, which can identify phase transition and its order-parameter. At low Reynolds number, there is only one dominant eigen microstate W_(1) of laminar flow. At Re_(c)^(1)= 53.6, there is a phase transition with the emergence of an eigen microstate pair W^(2,3) of pressure and velocity fields. Further at Re_(c)^(2)= 56, there is another phase transition with the emergence of two eigen microstate pairs W^(4,5) and W^(6,7). Using the renormalization group theory of eigen microstate,both phase transitions are determined to be first-order. The two-dimensional energy spectrum of eigen microstate for W^(1), W^(2,3) after Re_(c)^(1), W^(4-7) after Re_(c)^(2) exhibit-5/3 power-law behavior of Kolnogorov's K41 theory. These results reveal the complexity and provide an analysis of the Kármán Vortex Street from the perspective of phase transitions.

关键词： Kármán Vortex Street first-order phase transition eigen microstate approach renormalization group theory of eigen microstate

Increasing operational stability of journal bearing in hydraulic suspension micro-pump by herringbone grooved structure

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Science China(Technological Sciences) 2024年第3期67卷 853-862页

作者： HONG Tao xing GuanYing ZUO HuaiYu xue Song LUO XiaoBing State Key Laboratory of Coal Combustion School of Energy and Power EngineeringHuazhong University of Science and TechnologyWuhan 430074China

The operational stability of radial journal bearings is the bottleneck that limits the reliability of hydraulic suspension micropump. Due to self-excited vibrations, the whirl amplitude of the plain journal bearing(PJB) is large at high rotational speeds,which will accelerate wear failure. It has been proven that employing herringbone grooved journal bearing(HGJB) is an effective method to reduce the whirl amplitude and improve operational stability. However, enhancing the stability of journal bearings in micro-pumps by herringbone grooved structures has rarely been studied, and its effect needs to be verified. We validated the mechanism of the stability improvement with the CFD method and compared the dynamic characteristics of HGJB and PJB by rotor dynamics evaluation and experiment. The experimental results show that under the same conditions the whirl amplitude of the HGJB decreases by 29.61% in the x direction and by 24.09% in the y direction compared with that of the PJB. This study reveals the effect of the herringbone grooved structure on the operational stability of bearings and may provide guidance for the reliability improvement of hydraulic suspension micro-pump.

关键词： journal bearing herringbone groove hydrodynamic effect micro-pump

Verification of quantum networks using the GHZ paradox

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Communications in Theoretical Physics 2024年第10期76卷 57-63页

作者： Huan Ye xue Yang Ming-xing Luo School of Information Science and Technology Southwest Jiaotong University School of Computer Science and Cyber Security Chengdu University of Technology

The Greenberger–Horne–Zeilinger(GHZ) paradox shows that it is possible to create a multipartite state involving three or more particles in which the measurement outcomes of the particles are correlated in a way that cannot be explained by classical physics. We extend it to witness quantum networks. We first extend the GHZ paradox to simultaneously verify the GHZ state and Einstein–Podolsky–Rosen states on triangle networks. We then extend the GHZ paradox to witness the entanglement of chain networks consisting of multiple GHZ states. All the present results are robust against the noise.

关键词： GHZ paradox quantum entanglement quantum network

Comparative transcriptomic analysis of ovary and testis reveals sex-related genes in roughskin sculpin Trachidermus fasciatus

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Journal of Oceanology and Limnology 2024年第5期42卷 1673-1682页

作者： Dongxiu xue Sudong XIA Tengfei xing Yuqian GAO Jinxian LIU CAS Key Laboratory of Marine Ecology and Environmental Sciences Institute of OceanologyChinese Academy of SciencesQingdao 266071China Laboratory for Marine Ecology and Environmental Science Qingdao Marine Science and Technology CenterQingdao 266200China Tianjin Key Lab of Aqua-Ecology and Aquaculture Department of Fishery ScienceTianjin 300380China

The mechanisms underlying sex determination and differentiation have long intrigued researchers in the fields of development and evolutionary *** roughskin sculpin(Trachidermus fasciatus Heckel),displaying sexual dimorphism,provides an ideal model for studying the ***,both genetic and genomic information concerning sex determination and differentiation,such as gonadal transcriptome data in roughskin sculpin,are ***,we present the first gonadal transcriptomes of roughskin sculpin and identify sex-related *** identified 8531 differentially expressed genes(DEGs),among them 4065 were upregulated in the ovary and 4466 upregulated in the *** sex-related gene ontology(GO)terms were enriched in ovary-biased genes,including“binding of sperm to zona pellucida”,“egg coat formation”,“positive regulation of acrosome reaction”,“cell division”,and“cell cycle”,while the GO terms such as“spermatogenesis”,“sperm axoneme assembly”,“cilium assembly”,“cilium movement”,and“cilium movement involved in cell motility”were enriched in testis-biased ***,six KEGG pathways were significantly enriched in the ovary,whereas only one was enriched in the *** these DEGs,40 sex-related genes were identified,which including 26 testis-biased genes(such as Dmrtb 1,Gsdf,Sox 9 b,Wnt 4 b,Tcp 11 l 2,and Efhb),and 14 ovary-biased genes(such as Cyp 19 a 1 a,Foxh 1,Foxr 1,Gdf 3,Hsd 17 b 12,and Igf 2 bp 3).This gonadal transcript dataset would broaden our understanding of sex determination and differentiation mechanisms in roughskin sculpin,expand the genomic database,support future studies on sex-related gene functions,and facilitate molecular biology research into roughskin sculpin.

关键词： Trachidermus fasciatus transcriptome ovary testis sex-related gene

Fabrication of corrosion inhibiting microcapsules functional coating and their high-efficiency corrosion resistance

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Rare Metals 2024年第2期43卷 842-848页

作者： Hao-Ran Yun Lu Lu xue-Long Hao xing-Xiang Zhang School of Material Science and Engineering Tiangong UniversityTianjin300387China National Center of Analysis and Testing for Nonferrous Metals and Electronic Materials General Research Institute for Nonferrous MetalsBeijing100088China Guobiao(Beijing)Testing&Certification Co. Ltd.Beijing101407China

Benzotriazole(BTA)was loaded into calcium carbonate microsphere shell by self-assembly method and a new type of high-efficiency corrosion inhibiting microcapsules(CIMs)were fabricated,which were added and dispersed into epoxy resin coating to obtain a new corrosion resistance functional *** corrosion inhibition effect of benzotriazole on aluminum alloy matrix was verified by polarization curve *** effectiveness of the CIMs and their loading capacity on inhibitor were evaluated by scanning electron microscope,laser confocal Raman spectroscopy together with thermogravimetric analysis.

关键词： corrosion coating resistance

Experimental study on temperature fluctuations on plate surface induced by coaxial-jet flow

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Nuclear Science and Techniques 2024年第5期35卷 139-153页

作者： xue-Yao Xiong Zun-Quan Liu Guo-Yan Zhou xing Luo Shan-Tung Tu Key Laboratory of Pressure Systems and Safety(MOE) East China University of Science and TechnologyShanghai 200237China Institute of Thermodynamics Gottfried Wilhelm Leibniz University Hannover30823 GarbsenGermany

In nuclear reactors,temperature fluctuations of fluids may cause fatigue damage to adjacent structures;this is referred to as thermal *** on thermal striping in the upper plenum has mainly focused on fluid *** experimental studies have been reported on solid structures in a fluid field with a coaxial *** study entailed an experimental study of the temperature fluctuations in the fluid and on a plate surface caused by a coaxial *** temperature fluctuations of the fluid and plate surfaces located at different heights were *** cause of the temperature fluctuation was analyzed using a transient temperature *** results show that the mixing of the hot and cold fluids gradually becomes uniform in the positive axial *** average surface temperatures tended to be *** the jet reaches the plate surface,the swing of the jet center,contraction and expansion of the cold jet,and changes in the jet shape result in temperature *** intensity of the temperature fluctuation was affected by the *** attention should be paid when the plate is located at a lower height,and between the hot and cold-fluid nozzles.

关键词： Temperature fluctuation Thermal striping Coaxial jet Thermal mixing The upper plenum of nuclear reactor

New approach to measuring topological phase transitions utilizing Floquet technology

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Chinese Physics B 2024年第9期33卷 282-288页

作者： xue-Ying Yang Wei Wu Ping-xing Chen College of Sciences National University of Defense TechnologyChangsha 410073China

The Floquet technique provides a novel anomalous topological phase for non-equilibrium phase *** on the high symmetry of the quantum anomalous Hall model,the findings suggest a one-to-one correspondence between the average spin texture and the Floquet quasi-energy spectrum.A new approach is proposed to directly measure the quasienergy spectrum,replacing previous measurements of the average spin ***,we proposed a reliable experimental scheme based on ion trap *** scheme markedly reduces the measurement workload,improves the measurement fidelity,and is applicable to multiple platforms such as cold atoms and nuclear magnetic resonance.

关键词： topological phase transition Floquet technique ion trap