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Science china(Information Sciences) 2024年第7期67卷 224-239页

作者： Zhijia ZHAO Jiale WU Zhijie LIU We he c.L.Philip cheN School of Mechanical and Electrical Engineering Guangzhou University School of Intelligence Science and Technology and Key Laboratory of Intelligent Bionic Unmanned Systems of Ministry of Education University of Science and Technology Beijing School of computer Science and Engineering South China University of Technology Pazhou Lab

In this study, an adaptive neural network(NN) control is proposed for nonlinear two-degree-offreedom(2-DOF) helicopter systems considering the input constraints and global prescribed ***, radial basis function NN(RBFNN) is employed to estimate the unknown dynamics of the helicopter system. Second, a smooth nonaffine function is exploited to approximate and address nonlinear constraint functions. Subsequently, a new prescribed function is proposed, and an original constrained error is transformed into an equivalent unconstrained error using the error transformation and barrier function transformation methods. The analysis of the established Lyapunov function proves that the controlled system is globally uniformly bounded. Finally, the simulation and experimental results on a constructed Quanser's test platform verify the rationality and feasibility of the proposed control.

关键词： adaptive NN control 2-DOF helicopter global prescribed performance input constraints

Effects of lighting conditions and accommodation on the three-dimensional position of Visian implantable collamer lens

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Eye and Vision 2024年第3期10卷 31-40页

作者： Lingling Niu Zhe Zhang Huamao Miao Jing Zhao Xiaoying Wang Ji c.he Xingtao Zhou Department of Ophthalmology and Optometry Eye&ENT HospitalFudan UniversityShanghaiChina NHc Key Laboratory of Myopia(Fudan University) ShanghaiChina Key Laboratory of Myopia Chinese Academy of Medical SciencesShanghaiChina Shanghai Research center of Ophthalmology and Optometry ShanghaiChina New England college of Optometry MABostonUSA

Background To investigate the effects of lighting conditions and accommodation on the three-dimensional position of Visian implantable collamer lens(IcL V4c).Methods This observational study recruited 62 eyes of 31 myopia patients underwent IcL V4c *** segment optical coherence tomography(AS-OcT)assessed the anterior chamber depth(AcD),AcD-IcL(distance from the corneal endothelium to anterior surface of the IcL V4c),vault(distance between the posterior IcL V4c surface and anterior crystalline lens surface),and crystalline lens tilt under various lighting conditions and accommodation relative to the corneal topographic axis at one year after IcL V4c *** was defined as the scotopic condition,which was also the non-accommodative stimulus *** IcL V4c tilt was analyzed using *** significance level was set at Phe AcD-IcL values were similar under various lighting conditions(P=0.978)but decreased during accommodation(Phe vault was significantly smaller under mesopic and photopic conditions than the baseline(P=0.044 and Pctively)but remained unchanged during accommodation(P=0.058).The inferotemporal proportion of IcL V4c(88.7%,55 eyes)and crystalline lens(74.2%,46 eyes)tilts were not significantly different(P=0.063).crystalline lens under various lighting conditions and accommodation exhibited similar *** vertical tilt of IcL V4c was significantly larger under photopic conditions than the baseline(P=0.038).The horizontal and total tilts were significantly decreased during accommodation(P=0.043 and 0.013,respectively).conclusions The axial position of IcL V4c in the anterior chamber was stable under various lighting *** conditions and accommodation may influence vertical,horizontal and total tilts of IcL V4c.

关键词： Implantable collamer lens Anterior segment optical coherence tomography Myopia Tilt

Distinct Electrical and Mechanical Responses of a cu-10Fe composite Prepared by Hot-Pressed Sintering and Post Treatment

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 255-265页

作者： X.Y.Yue S.Y.Peng X.Zhang c.N.he Y.Z.Tian Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) School of Materials Science and EngineeringNortheastern UniversityShenyang110819China School of Materials Science and Engineering and Tianjin Key Laboratory of composite and Functional Materials Tianjin UniversityTianjin300350China Research centre for Metallic Wires Northeastern UniversityShenyang110819China

A cu-10wt%Fe composite was prepared through hot-pressed sintering,and the material was subsequently solution *** hot-pressed sintered and solution treated materials were rolled and *** precipitation behavior and performance changes were systematically studied by using scanning electron microscopy and transmission electron *** contrast to the hot-pressed sintered specimen,the solution treatment significantly affects the thermal stability and properties of the cu-10wt%Fe *** cu-10wt%Fe composite was prepared after solid solution,cold rolling and aging at 773 K for 1 h,and it obtained excellent tensile strength of 494 MPa,uniform elongation of 16.3%,electrical conductivity of 51.1%IAcS and softening temperature of 838 *** for the distinct difference in thermal stability and properties between hot-pressed sintered and solution treated specimens were *** findings provide a theoretical basis for designing high-performance cu-based in-situ composites by post treatment.

关键词： cu-Fe composite Hot-pressed sintering Thermal stability Strength Electrical conductivity

chien-physics-informed neural networks for solving singularly perturbed boundary-layer problems

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Applied Mathematics and Mechanics(English Edition) 2024年第9期45卷 1467-1480页

作者： Long WANG Lei ZHANG Guowei he The State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China School of Engineering Sciences University of Chinese Academy of SciencesBeijing 100049China

A physics-informed neural network(PINN)is a powerful tool for solving differential equations in solid and fluid ***,it suffers from singularly perturbed boundary-layer problems in which there exist sharp changes caused by a small perturbation parameter multiplying the highest-order *** this paper,we introduce chien's composite expansion method into PINNs,and propose a novel architecture for the PINNs,namely,the chien-PINN(c-PINN)*** novel PINN method is validated by singularly perturbed differential equations,and successfully solves the wellknown thin plate bending *** particular,no cumbersome matching conditions are needed for the c-PINN method,compared with the previous studies based on matched asymptotic expansions.

关键词： physics-informed neural network(PINN) singular perturbation boundarylayer problem composite asymptotic expansion

cooperative composites anchored with single atom Pb and carbon confined PbO nanoparticles for superior lead-carbon batteries

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Journal of Energy chemistry 2024年第10期97卷 486-497页

作者： Puqiang he Yi Yang Hui Huang Jing Huang Hongbiao Wang Yapeng he Zhongcheng Guo Faculty of Metallurgical and Energy Engineering Kunming University of Science and Technology Metallurgical Electrode Material Engineering Technology Research center of Yunnan Province Kunming hendera Technology co.LTD.

The mitigation of sulphation and parasitic hydrogen evolution is considered as prominent research emphasis for the development of lead-carbon batteries（LcBs） in large-scale energy storage ***,cooperative Pb-c composites consisting of single atom Pb and carbon-encapsulated PbO nanoparticles were prepared by freeze-drying technique and pyrolytic reduction to address above *** innovative use of Pb2+to cross-link sodium alginate enabled a uniform distribution of Pb in the composites,generating Pb-c-PbO three-phase *** analysis and theoretical calculations revealed the synergistic interactions between single-atom Pb and PbO nanoparticles in suppressing parasitic hydrogen evolution and promoting the adsorption of Pb *** presence of monatomic Pb and PbO enhanced the affinity of the composites for the negative active materials and facilitated the transformation of the active materials from bulk into spherical shapes to enhance the specific surface area,thereby counteracting *** the coordinated integration of various functionalities offered by Pb@c-x,the cycle life of the battery at HRPSoc reaches 7025 cycles,which is two times for LcB with pure carbon ***,the discharge capacity increased from 3.52 to 3.79 *** study provides substantial insights into the construction of Pb-c composites for LcBs to inhibit negative sulphation and hydrogen evolution.

关键词： Hydrogen evolution Lead carbon composites Lead-carbon battery Negative sulphation Single-atom

Geoengineering: proactive measures to tackle climate change

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National Science Review 2024年第4期11卷 299-304页

作者：朱禾 the editorial office of NSR in Beijing

As of 20 August, 2023, extensive parts of northern china including the capital city of Beijing had experienced arguably the hottest summer in recent years, recording consecutive days of high temperatures at or near 40°c. Against this backdrop, National Science Review (NSR) organized a web forum on a climate-related topic that needs more exposure to chinese public and researchers alike:geoengineering.

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Selective N-Methylation of N-Methylaniline with cO_(2) and H_(2) over cu/In_(2)O_(3) catalyst

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chinese Journal of chemistry 2024年第3期42卷 276-282页

作者： Huan Zheng Bo Qian Lin he State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhouGansu730000 China University of chinese Academy of Sciences Beijing100049 China

N-Methylation of amines with cO_(2) and H2 is a potential approach for cO_(2) utilization because N-methylated amines can be used as solvents and organic intermediates. In_(2)O_(3)-supported cu (cu/In_(2)O_(3)) acts as an effective heterogeneous catalyst for N-methylation reaction of N-methylaniline (MA) with cO_(2) and H_(2),showing higher N,N-dimethylaniline (DMA) selectivity than other supported cu catalysts. On one hand,the dispersion of cu can be improved by the defective In_(2)O_(3) support. On the other hand,In_(2)O_(3) support is active in the dissociative adsorption of cO_(2) through c—O bond breaking. In addition,the H_(2) dissociation ability of In_(2)O_(3) can also be enhanced by cu. The combination of cu and In_(2)O_(3) is effective in the activation of cO_(2),the adsorption of intermediate N-methylformanilide (MFA),the hydrogenation of MFA to DMA and the prohibition of c—N bond cleavage side reactions,thereby enhancing the reaction rate of MA conversion and the selectivity to DMA.

关键词： N-Methylation cO_(2) cu/In_(2)O_(3) Supported catalysts heterogeneous catalysis

Regulating Melting Process in the Energy Storage of Solid-Liquid PcM based on Double MRT-LBM Simulation

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Journal of Thermal Science 2024年第5期33卷 1688-1700页

作者： cheN Weiqi SONG Zhichao QUAN Dongliang he Yurong School of Energy Science&Engineering Harbin Institute of TechnologyHarbin 150001China heilongjiang Key Laboratory of New Energy Storage Materials and Processes Harbin 150001China Zhengzhou Research Institute of Harbin Institute of Technology Zhengzhou 450000China Innovation&Research Institute of Hiwing Technology Academy Beijing 100074China

The melting process of solid-liquid phase change materials(PcM)has a significant impact on their energy storage *** more effectively apply solid-liquid PcM for energy storage,it is crucial to study the regulation of melting process of solid-liquid PcM,which is numerically investigated based on double multiple relaxation time lattice Boltzmann method(MRT-LBM)in this *** this work we pay more attention to the effects of different Stefan numbers(Ste)and Rayleigh numbers(Ra)on the melting *** results indicate that the PcM melting is greatly influenced by the Ste number and Ra number,which can be divided into the heat conduction dominant stage and the convection dominant stage,according to the onset time of convection Fo_(c).In order to describe the contribution of the heat conduction dominant stage to the whole melting process quantitatively,we firstly propose the ratio of the heat conduction dominant stage R_(pc),which can be defined as the ratio of Fo_(c)to the complete melting time Fo_(M).R_(pc)gradually decreases as the Ra number increases,and when the Ste number rises:R_(pc)=90.0%when Ste=1.0 and Ra=1×10^(5),R_(pc)=39.6%when Ste=0.1 and Ra=1×10^(5),and R_(pc)=14.0%when Ste=1.0 and Ra=1×10~7.A regime map about the effects of different Ste numbers and Ra numbers on R_(pc)has been further *** discovered findings would be helpful in regulating melting process in the energy storage of solid-liquid PcM.

关键词： latent thermal energy storage solid-liquid phase change double MRT-LBM dominant melting mechanism

Enhancing lithium-sulfur battery performance with In_(2)O_(3)-In_(2)S_(3)@NSc heterostructures:Synergistic effects of double barrier and catalytic transformation

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Journal of Materials Science & Technology 2024年第2期169卷 105-114页

作者： Deqing he chunyu Zhu Yutao Huo Zhonghao Rao School of Energy and Environmental Engineering Hebei University of TechnologyTianjin 300401China hebei Key Laboratory of Thermal Science and Energy clean Utilization Hebei University of TechnologyTianjin 300401China School of Low-carbon Energy and Power Engineering China University of Mining and TechnologyXuzhou 221116China

The sluggish redox reaction kinetics of lithium polysulfides(LiPSs)are considered the main obstacle to the commercial application of lithium-sulfur(Li-S)*** accelerate the conversion by catalysis and inhibit the shuttling of soluble LiPSs in Li-S batteries,a solution is proposed in this *** solution involves fabrication of N,S co-doped carbon coated In_(2)O_(3)/In_(2)S_(3)heterostructure(In_(2)O_(3)-In_(2)S_(3)@NSc)as a multifunctional host material for the *** In_(2)O_(3)-In_(2)S_(3)@NSc composite can reduce the Gibbs free energy for the conversion reactions of LiPSs,which results in superior *** synergy between different components in In_(2)O_(3)-In_(2)S_(3)@NSc and the unique 3D structure facilitate ion and electron transport in Li-S *** In_(2)O_(3)-In_(2)S_(3)@NSc/Li 2 S 6 cathode exhibits excellent rate capacity,with a capacity of 599 mAh g−1 at 5.5 c,and good cycle stability,with a capacity of 436 mAh g^(−1)after 1000 cycles at 1 ***,this study proposes a promising solution to improve the energy storage properties of Li-S batteries,which could potentially facilitate the commercialization of Li-S batteries.

关键词： Li-S battery Multifunctional host material Synergy heterostructures Energy storage properties

A signaling cascade mediating fruit trait development via phosphorylation-modulated nuclear accumulation of JAZ repressor

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Journal of Integrative Plant Biology 2024年第6期66卷 1106-1125页

作者： Wei Wang Jinyao Ouyang Yating Li changsheng Zhai Bing he Huahan Si Kunsong chen Jocelyn K.c.Rose Wensuo Jia college of Horticulture China Agricultural UniversityBeijing 100193China college of Agriculture and Biotechnology Zhejiang UniversityZijingang CampusHangzhou 310058China Plant Biology Section School of Integrative Plant ScienceCornell UniversityIthaca14853NYUSA Institute of Horticulture crops Xinjiang Academy of Agricultural SciencesUrumqi 830000China

It is generally accepted that jasmonate-ZIM domain(JAZ)repressors act to mediate jasmonate(JA)signaling via cORONATINE-INSENSITIVE1(cOI1)-mediated ***,we report a cryptic signaling cascade where a JAZ repressor,FvJAZ12,mediates multiple signaling inputs via phosphorylation-modulated subcellular translocation rather than the cOI1-mediated degradation mechanism in strawberry(Fragaria vesca).FvJAZ12 acts to regulate flavor metabolism and defense response,and was found to be the target of Fv MPK6,a mitogen-activated protein kinase that is capable of responding to multiple signal ***6 phosphorylates FvJAZ12 at the amino acid residues S179 and T183 adjacent to the PY residues,thereby attenuating its nuclear accumulation and relieving its repression for FvMYc2,which acts to control the expression of lipoxygenase 3(FvLOX3),an important gene involved in JA biosynthesis and a diverse array of cellular *** data reveal a previously unreported mechanism for JA signaling and decipher a signaling cascade that links multiple signaling inputs with fruit trait development.

关键词： defense response JAZ repressor phosphorylation strawberry subcellular translocation