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Atomically Dispersed Ruthenium Catalysts with Open Hollow Structure for Lithium-Oxygen Batteries

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Nano-Micro Letters 2024年第2期16卷 154-164页

作者： Xin chen yu Zhang Chang chen Huinan Li yuran Lin Ke yu Caiyun Nan chen chen Beijing Advanced innovation Center for Materials Genome Engineering Institute of Solid State ChemistryUniversity of Science and Technology BeijingBeijing 100083People’s Republic of China Engineering Research Center of Advanced Rare Earth Materials Department of ChemistryTsinghua UniversityBeijing 100084People’s Republic of China Beijing Key Laboratory of Energy Conversion and Storage Materials institution College of ChemistryBeijing Normal UniversityBeijing 100875People’s Republic of China

Lithium–oxygen battery with ultrahigh theoretical energy density is considered a highly competitive next-generation energy storage device,but its practical app.ication is severely hindered by issues such as difficult decomposition of discharge products at ***,we have developed N-doped carbon anchored atomically dispersed Ru sites cathode catalyst with open hollow structure(h-RuNC)for Lithium–oxygen *** one hand,the abundance of atomically dispersed Ru sites can effectively catalyze the formation and decomposition of discharge products,thereby greatly enhancing the redox *** the other hand,the open hollow structure not only enhances the mass activity of atomically dispersed Ru sites but also improves the diffusion efficiency of catalytic ***,the excellent activity from atomically dispersed Ru sites and the enhanced diffusion from open hollow structure respectively improve the redox kinetics and cycling stability,ultimately achieving a high-performance lithium–oxygen battery.

关键词： Atomically dispersed Open hollow structure Discharge product Lithium Oxygen battery

State-of-the-art on the anchorage performance of rock bolts subjected to shear load

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international Journal of Coal Science & Technology 2024年第1期11卷 1-30页

作者： yu chen Haodong Xiao School of Civil Engineering Sun Yat-sen UniversityZhuhai519082China

Rock bolts are extensively utilized in underground engineering as a means of offering support and stability to rock masses in tunnels,mines,and other underground *** environments of high ground stress,faults or weak zones can frequently arise in rock formations,presenting a significant challenge for engineering and potentially leading to underground engineering *** bolts serve as a crucial structural element for the transmission of tensile stress and are capable of withstanding shear loads to prevent sliding of weak zones within rock ***,a complete understanding of the behavior of rock bolts subjected to shear loads is *** paper presents a state-of-the-art review of the research progress of rock bolts subjected to shear load in three categories:experiment,numerical simulation,and analytical *** review focuses on the research studies and developments in this area since the 1970s,providing a comprehensive overview of numerous factors that influence the anchorage performance of rock *** factors include the diameter and angle of the rock bolt installation,rock strength,grouting material,bolt material,borehole diameter,rock bolt preload,normal stress,joint surface roughness and joint expansion *** paper reviews the improvement of mechanical parameter setting in numerical simulation of rock bolt ***,it delves into the op.imization of the analytical model concerning rock bolt shear theory,approached from the perspectives of both Elastic foundation beam theory coupled with Elastoplasticity theory and Structural mechanic *** significance of this review lies in its ability to provide insights into the mechanical behavior of rock *** paper also highlights the limitations of current research and guidelines for further research of rock bolts.

关键词： Rock bolt Shear load Shear test Numerical simulation Analytical model

Mott insulator-density ordered superfluid transition and‘shamrock transition’in a frustrated triangle lattice

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Communications in Theoretical physics 2024年第3期76卷 157-164页

作者： Ce Wang yu chen School of physics Science and Engineering Tongji UniversityShanghai200092China institute for Advanced Study Tsinghua UniversityBeijing100084China Graduate School of China Academy of Engineering physics Beijing100193China

Density order is usually a consequence of the competition between long-range and short-range *** we report a density ordered superfluid emergent from a homogeneous Mott insulator due to the competition between frustrations and local *** transition is found in a Bose–Hubbard model on a frustrated triangle lattice with an extra p.iring ***,we find a quantum phase transition between two different density ordered superfluids,which is beyond the Landau–Ginzburg(LG)paradigm.A U(1)symmetry is emergent at the critical p.int,while the symmetry in each density ordered superfluid is Z_(2)×Z_(3).We call the transition a‘shamrock transition’,due to its degenerate ground state in the parameter space being a shamrock-like curve rather than a circle in an LG-type *** low energy theories are established for the two transitions mentioned above and we find their resemblance and differences with clock models.

关键词： frustrated magnets superfluid mott insulator density wave ordered phase clock model

Cooperative game penetration guidance for multiple hypersonic vehicles under safety critical framework

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Chinese Journal of Aeronautics 2024年第1期37卷 247-255页

作者： Jieqing chen Ruisheng SUN yu LU School of Energy and power Engineering Nanjing University of Science and TechnologyNanjing 210094China

The rapid development of the anti-missile weapon technology brings new challenges to the cooperative penetration strategy solution and the guidance law design for Hypersonic Vehicles(HVs).This paper studies the coordinated game penetration guidance problem for multiple hypersonic vehicles faced with space threat areas.A scheme for seeking cooperative game penetration guidance strategy under safety critical control framework is *** this scheme,a multiHV cooperative game model is proposed in a minimum op.imization form which can simp.ify the solving process and accelerate the computing ***,a second-order control barrier function is developed to transform the imp.icit nonlinear constraints of the proposed model into linear *** order to obtain better performance of guidance strategy,a composite guidance law under the safety critical control framework is presented to allocate guidance strategies approp.iately in the whole *** is shown that the proposed scheme can guarantee successful penetration while avoiding threat ***,a comparative simulation with a two-on-three game is conducted to verify the effectiveness of the proposed method.

关键词： Hypersonic vehicles Safety critical control penetration game Space constraints Cooperative guidance

Design and Gait planning of a Worm-inspired Metameric Robot for pipe Crawling

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Journal of Bionic Engineering 2024年第3期21卷 1265-1277页

作者： yu Liu Qingbiao Shi Zhen chen pen-Tung Sah institute of Micro-Nano Science and Technology Xiamen UniversityXiamen361102China

The earthworm has been attracted much attention in the research and development of biomimetic robots due to their unique locomotion mechanism,compact structure,and small motion *** paper presents a new design and prototype of a worm-inspired metameric robot with a movement pattern similar to that of *** robot consists of multiple telescopic modules connected in series through joint *** telescopic module mimics the contraction and elongation motion modes of the earthworm segments.A kinematic and dynamic analysis is conducted on the telescopic module,and an input torque calculation method is provided to ensure sufficient friction between the robot and the pipe *** gait modes of the prototype robot for straight and turning locomotion are introduced,and these modes are extended to robots constructed by different numbers of telescopic *** addition,a method is proposed to increase the friction between the robot and the pipe wall in the aforementioned gait modes without changing the robot structure,thereby improving the robot’s motion ability in *** theoretical model of gait modes has also been validated through gait *** findings of this paper would provide a useful basis for the design,modeling,and control of future worm inspired robots.

关键词： Bio-inspired robot Spatial linkage mechanism Kinematics model peristaltic locomotion

Generic Existence of infinitely Many Non-contractible Closed Geodesics on Compact Space Forms

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Acta Mathematica Sinica,English Series 2024年第7期40卷 1674-1684页

作者： Hui Liu yu chen Wang School of Mathematics and Statistics Wuhan UniversityWuhan430072P.R.China School of Mathematics Tianjin Normal UniversityTianjin300384P.R.China

Let M=S^(n)/Γand h be a nontrivial element of finite order p.inπ_(1)(Μ),where the integers n,p≥2,Γis a finite abelian group which acts freely and isometrically on the n-sphere and therefore M is diffeomorp.ic to a compact space *** this paper,we prove that there are infinitely many non-contractible closed geodesics of class[h]on the compact space form with C^(r)-generic Finsler metrics,where 4≤r≤∞.The conclusion also holds for Cr-generic Riemannian metrics for 2≤r≤∞.The proof is based on the resonance identity of non-contractible closed geodesics on compact space forms.

关键词： Compact space forms non-contractible closed geodesics generic Finsler metrics resonance identity

progress on Bionic Textured Cutting Tools:A Review and prospects

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Journal of Bionic Engineering 2024年第1期21卷 19-55页

作者： Hong Wei Guangjun chen Zhuang chen Zhiwei yu Jiashuai Huang Tianjin Key Laboratory of High Speed Cutting and precision processing Tianjin 300222China School of Mechanical Engineering Tianjin University of Technology and EducationTianjin 300222China

Cutting tools are known as the“productivity”of the manufacturing industry,which affects the production efficiency and quality of the workpiece,and has become the focus of research and attention in academia and ***,traditional cutting tools often suffer from adhesion or wear during the cutting process,which considerably reduces the cutting efficiency and service life of the tools,and makes it difficult to meet current production *** solve the above problems,scholars have introduced bionics into the tool’s design,applying the microscopic structure of the biological surface to the tool surface to alleviate the tool’s *** paper mainly summarizes the research progress of bionic textured cutting ***,categorize whether the bionic texture design is inspired by a single organism or multiple ***,it is discussed that the non-smooth surface of the biological surface has five characteristics:hydrop.ilic lubricity,wear resistance,drag reduction and hydrophobicity,anti-adhesion,and arrangement,and the non-smooth structure of these different characteristics are app.ied to the surface of the tool is designed with bionic ***,the cutting performance of bionic textured cutting tools is *** anti-friction and wear-resisting mechanism of bionic textured cutting tools is ***,some pending problems and perspectives have been proposed to provide new inspirations for the design of bionic textured cutting tools.

关键词： Bionic textured cutting tools Biological microstructure characteristics Cutting performance Anti-friction and wear-resisting mechanism

Cronkhite-Canada syndrome with esophagus involvement and sixyear follow-up:A case report

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World Journal of Gastroenterology 2024年第8期30卷 984-990页

作者： yu-chen Tang Department of Endocrinology The First Affiliated Hospital of Ningbo UniversityNingbo 315000Zhejiang ProvinceChina

BACKGROUND Cronkhite-Canada syndrome(CCS)is a rare,noninherited disease characterized by gastrointestinal polyposis with diarrhea and ectodermal *** polyps are distributed through the whole digestive tract,and they are common in the stomach and colon but very uncommon in the *** SUMMARY Here,we present a case of a 63-year-old man with skin hyperpigmentation accompanied by diarrhea,alopecia,and loss of his *** data indicated anemia,hypoalbuminemia,hypocalcemia,hypokalemia,and positive fecal occult *** showed numerous polyps scattered throughout the digestive tract,including the *** was treated with nutritional support and glucocorticoids with remission of his *** Comprehensive treatment led by hormonal therapy can result in partial or full remission of clinical *** should be individualized for each patient according to their therapy *** endoscopy is necessary for assessing mucosal disease activity and detecting malignant transformation.

关键词： Cronkhite-Canada syndrome Gastrointestinal polyposis Hormonal therapy prognosis Case report

Human pangenome:far-reaching imp.ications in precision medicine

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Frontiers of Medicine 2024年第2期18卷 403-409页

作者： Yingyan yu Hongzhuan chen Department of General Surgery of Ruijin Hospital Shanghai Institute of Digestive Surgeryand Shanghai Key Laboratory for Gastric NeoplasmsShanghai Jiao Tong University School of MedicineShanghai200025China Shuguang Lab for Future Health Shanghai Frontier Science Center of TCM Chemical BiologyShanghai University of Traditional Chinese MedicineShanghai201203China

*** May 11,2023,the internationally renowned journal Nature announced that a first draft of the human pangenome reference has been constructed[1].This research was carried out by the Human pangenome Reference Consortium(HpRC).One month later,on June 14,2023,a pangenome reference of 36 Chinese populations was published on journal Nature[2],which was performed by Chinese pangenome Consortium(CpC).As the scientists p.inted out that since the Human Genome project(HGp)published the human reference genome,it provided a reference bluep.int for genomic ***,the limitations of the human reference genome have gradually emerged,and it is difficult to reflect the genome diversity of the"human"species.

关键词： Human journal limitations