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Journal of Materials Science & Technology 2017年第7期33卷 744-750页

作者： b.Q.Geng Y.Q.Ma M.Wang Z.L.Ding W.H.Song b.c.zhao Key Laboratory of Materials Physics Institute of Solid State Physics Chinese Academy of Sciences Hefei 230031 China

The coFe_2alloy（cF） was prepared by reducing coFe_2O_4 in the H_2 ambient. Subsequently the cF sample was nitrided in the NH_3 atmosphere to produce the composite of coFe_2N and coFe_2. The magnetostriction, thermal expansion, resistivity and corrosion resistance of cF sample and the nitrided sample（cFN）at 1000？c were investigated. The saturation magnetostriction coefficiency λ_s and thermal expansion coefficient ？ at 300 K for the nitrided cFN were 50 ppm and 10 ppm/K, respectively, approximately equal to those for the cF sample. However, compared with cF, cFN presents a decrease in temperature coefficient R_λ（300 K） of magnetostriction by 11%. The smaller resistivity and improved corrosion resistance in the H_2SO_4 solution may expand the applications of the coFe_2 in the fields needing lower resistivity or in the acidic environment.

关键词： coFe alloy coFe_2N alloy Magnetostriction Resistivity corrosion resistance

The study of trial-mix strength calculation equation for c60 concrete under certain steam curing schedule

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The study of trial-mix strength calculation equation for C60...

A study on the influence of coarse aggregate on rheological properties of self-compacting concrete

TEIM2015第六届无机材料结构、性能及测试表征技术研讨会

作者： Y.Wang Y.c.Jiang b.c.zhao 中国建材检验认证集团股份有限公司

This article selects raw materials from different areas to design c60 concrete,based on JGJ55-2011Specification for mix proportion design of ordinary *** specimens are cured under standard curing schedule or steam curing *** compressive strengths of requirement age are *** result shows that the compressive strengths under steam curing schedule are lower than that under standard curing schedule,and the difference value is about *** the trial-mix strength calculation equation of c60 concrete under standard curing schedule,the relationship between the two kinds of curing schedules is analyzed,and then the trial-mix strength calculation equation of c60 concrete under the steam curing schedule is found.

关键词： The study of trial-mix strength calculation equation for c60 concrete under certain steam curing schedule

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A study on the influence of coarse aggregate on rheological ...

Leveraging the potential of big genomic and phenotypic data for genome-wide association mapping in wheat

TEIM2015第六届无机材料结构、性能及测试表征技术研讨会

作者： Y.c.Jiang Y.Wang b.c.zhao H.W.Yue 中国建材检验认证集团股份有限公司

This paper presences the influence of coarse aggregate-space coefficient on the rheological properties of self-compacting concrete(Scc).The results indicate that coarse aggregate-space coefficient has significant influence on slump flow and V-funnel flow time of Scc,when the maximum aggregate particle size is 16mm and the volume ratio of sand and motor is 0.43,meanwhile water binder ratio is *** higher the coarse aggregate-space coefficient,the lager the slump flow,the shorter the V-funnel flow *** range of coarse aggregate-space coefficient of Scc is suitable for 1.31～1.58 under the condition of the *** suitable range can guarantee excellent rheological properties and stability of Scc *** is little effect of coarse aggregate-space coefficient on compressive strength in this paper tests.

关键词： A study on the influence of coarse aggregate on rheological properties of self-compacting concrete

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The crop Journal 2024年第3期12卷 803-813页

作者： Moritz Lell Yusheng zhao Jochen c.Reif Leibniz Institute of Plant Genetics and crop Plant Research(IPK) Corrensstraße 3D-06466 SeelandGermany

Genome-wide association mapping studies(GWAS)based on big Data are a potential approach to improve marker-assisted selection in plant *** number of available phenotypic and genomic data sets in which medium-sized populations of several hundred individuals have been studied is rapidly *** these data and using them in GWAS could increase both the power of QTL discovery and the accuracy of estimation of underlying genetic effects,but is hindered by data heterogeneity and lack of *** this study,we used genomic and phenotypic data sets,focusing on central European winter wheat populations evaluated for heading *** explored strategies for integrating these data and subsequently the resulting potential for *** interoperability between data sets was greatly aided by some overlapping genotypes and a linear relationship between the different phenotyping protocols,resulting in high quality integrated phenotypic *** this context,genomic prediction proved to be a suitable tool to study relevance of interactions between genotypes and experimental series,which was low in our *** to expectations,fewer associations between markers and traits were found in the larger combined data than in the individual experimental ***,the predictive power based on the marker-trait associations of the integrated data set was higher across data ***,the results show that the integration of medium-sized to big Data is an approach to increase the power to detect QTL in *** results encourage further efforts to standardize and share data in the plant breeding community.

关键词： big Data Genome-wide association study Data integration Genomic prediction Wheat

Effects of layer interactions on instantaneous stability of finite Stokes flows

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Applied Mathematics and Mechanics(English Edition) 2024年第1期45卷 69-84页

作者： chen zhao Zhenli cHEN c.T.MUTASA Dong LI School of Aeronautics Northwestern Polytechnical UniversityXi'an 710072China

The stability analysis of a finite Stokes layer is of practical importance in flow control. In the present work, the instantaneous stability of a finite Stokes layer with layer interactions is studied via a linear stability analysis of the frozen phases of the base flow. The oscillations of two plates can have different velocity amplitudes, initial phases, and frequencies. The effects of the Stokes-layer interactions on the stability when two plates oscillate synchronously are analyzed. The growth rates of two most unstable modes when δ ckness and the half height of the channel, respectively. However, their vorticities are different. The vorticity of the most unstable mode is symmetric, while the other is asymmetric. The Stokes-layer interactions have a destabilizing effect on the most unstable mode when δ bilizing effect when δ > 0.68. However, the interactions always have a stabilizing effect on the other unstable mode. It is explained that one of the two unstable modes has much higher dissipation than the other one when the Stokes-layer interactions are strong. We also find that the stability of the Stokes layer is closely related to the inflectional points of the base-flow velocity profile. The effects of inconsistent velocity-amplitude, initial phase, and frequency of the oscillations on the stability are analyzed. The energy of the most unstable eigenvector is mainly distributed near the plate of higher velocity amplitude or higher oscillation frequency. The effects of the initial phase difference are complicated because the base-flow velocity is extremely sensitive to the initial phase.

关键词： finite Stokes layer instantaneous stability Stokes-layer interaction asynchronous oscillation

Data-driven Static Equivalence with Physics-informed Koopman Operators

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cSEE Journal of Power and Energy Systems 2024年第1期10卷 432-438页

作者： Wei Lin changhong zhao Maosheng Gao c.Y.chung Department of Electrical Engineering The Hong Kong Polytechnic UniversityHong Kong SARChina Department of Information Engineering The Chinese University of Hong KongHong Kong SARChina School of Electrical Engineering Chongqing UniversityChongqing 400044China

With deployment of measurement units,fitting static equivalent models of distribution networks(DNs)by linear regression has been recognized as an effective method in power flow analysis of a transmission *** volatility of measurements caused by variable distributed renewable energy sources makes it more difficult to accurately fit such equivalent *** tackle this challenge,this letter proposes a novel data-driven method to improve equivalency accuracy of DNs with distributed energy *** letter provides a new perspective that an equivalent model can be regarded as a mapping from internal conditions and border voltages to border power *** mapping can be established through 1)Koopman operator theory,and 2)physical features of power flow equations at the root node of a *** of the proposed method is demonstrated on the IEEE 33-bus and IEEE 136-bus test systems connected to a 661-bus utility system.

关键词： Data-driven distribution network Koopman operator theory static equivalent model

Adaptive neural network control of a 2-DOF helicopter system considering input constraints and global prescribed performance

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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

Generalized time-dependent generator coordinate method for induced fission dynamics

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Frontiers of physics 2024年第4期19卷 1-12页

作者： b.Li D.Vretenar T.Nikšić J.zhao P.W.zhao J.Meng State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China Physics Department Faculty of ScienceUniversity of Zagreb10000 ZagrebCroatia center for circuits and Systems Peng Cheng LaboratoryShenzhen 518055China

The generalized time-dependent generator coordinate method(TD-GcM)is extended to include pairing *** correlated GcM nuclear wave function is expressed in terms of time-dependent generator states and weight *** particle–hole channel of the effective interaction is determined by a Hamiltonian derived from an energy density functional,while pairing is treated dynamically in the standard bcS approximation with time-dependent pairing tensor and single-particle occupation *** the inclusion of pairing correlations,various time-dependent phenomena in open-shell nuclei can be described more *** model is applied to the description of saddle-to-scission dynamics of induced *** generalized TD-GcM charge yields and total kinetic energy distribution for the fission of 240Pu,are compared to those obtained using the standard time-dependent density functional theory(TD-DFT)approach,and with available data.

关键词： nuclear density functional theory generator coordinate method fission dynamics

Spatial distributions of soil nutrients affected by land use,topography and their interactions,in the Loess Plateau of china

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International Soil and Water conservation Research 2024年第1期12卷 227-239页

作者： Wenxin Zhou changjia Li Wenwu zhao Lindsay c.Stringer bojie Fu State Key Laboratory of Earth Surface Processes and Resource Ecology Faculty of Geographical ScienceBeijing Normal UniversityBeijingChina Institute of Land Surface System and Sustainable Development Faculty of Geographical ScienceBeijing Normal UniversityBeijingChina Department of Environment and Geography University of YorkYorkUK York Environmental Sustainability Institute University of YorkYorkUK

Soil nutrient availability and their spatial distributions are strongly related to land use and landscape *** study aims to address the knowledge gap regarding the interaction between these factors and the underlying *** selected five land uses(grassland with Artemisia gmelinii,woodland with Robinia pseudoacacia,shrubland with caragana korshinskii and Hippophae rhamnoides,and apple orchard with Malus pumila)and nine slope positions across hillslopes in the Loess Plateau,china,to investigate their combined effects on the contents and stocks of soil organic carbon(SOc),total nitrogen(TN)and total phosphorus(TP).Parametric and non-parametric statistical tests were conducted to determine the significant differences in the means or the medians of the soil nutrient *** showed that the SOc and TN contents of shrubland with caragana korshinskii were statistically significantly greater than those of the grassland(pc and TN contents generally decreased from the upper slope to the middle slope,and to the foot slope for the grassland,woodland and shrublands,and on the contrary,an increasing trend from the upper slope,to the middle slope,and to the foot slope was identified for the apple *** study highlights that land use,slope position and their interaction have significant effects on the spatial distributions of soil *** provides essential empirical evidence for the identification of the optimal vegetation type and slope positions in land management and vegetation restoration activities.

关键词： Soil organic carbon Total nitrogen Total phosphorus Slope position Vegetation restoration

black hole shadows in Einstein-bel-Robinson gravity

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chinese Physics c 2024年第5期48卷 272-283页

作者： b.Hamil b.c.Lütfüoğlu Laboratoire de Physique Mathématique et Subatomique Facultédes Sciences ExactesUniversitéConstantine 1ConstantineAlgeria Department of Physics University of Hradec KrálovéRokitanského 6250003 Hradec KrálovéCzechia

Gravity models given by higher-order scalar curvature corrections are believed to bear important consequences. Einstein-bel-Robinson (EbR) gravity with quartic curvature modification motivated Sajadi et al. to explore static spherically symmetric black hole solutions using perturbative methods. In this study, inspired by their work, we investigate AdS black hole shadows in EbR gravity and demonstrate how the gravity parameter alters the energy emission rate. Finally, we address the same problem in the presence of plasma, because the black holes are thought to be surrounded by a medium that changes the geodesic of photons.

关键词： black hole shadows Einstein-bel-Robinson gravity plasma