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Science China(Technological Sciences) 2024年第3期67卷 696-708页

作者： GUO MingHui rong YouMin huang Yu feng XiaoLin HU HaiDong WU CongYi ZHANG GuoJun State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and Technology Wuhan 430074China School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China Faculty of Engineering and Life Sciences Universiti Selangor Bestari JayaSelangor 45600Malaysia

Oil film vortex severely reduces the stability of hydrostatic bearings. A solid-liquid interface with drag and slip properties can weaken the oil film vortex of the bearing. Here, a combined picosecond laser ablation and chemical modification method is proposed to prepare surfaces with microbulge array structure on 6061 aluminum alloy substrates. Because of the low surface energy of the perfluorododecyltriethoxysilane modification and the bulge geometry of the microbulge array structure, the surface shows excellent superhydrophobicity. The optimum contact angle in air for water is 164°, and that for oil is 139°. Two surfaces with “lotus-leaf effect” and “rose-petal effect” were obtained by controlling the processing parameters. The drag reduction properties of superhydrophobic surfaces were systematically investigated with slip lengths of 22.26 and 36.25 μm for deionized water and VG5 lubricant, respectively. In addition, the superhydrophobic surface exhibits excellent mechanical durability and thermal stability. The proposed method provides a new idea for vortex suppression in hydrostatic bearings and improves the stability of bearings in high-speed operation.

关键词： superhydrophobicity surface ultrafast laser drag reduction solid-liquid interface microbulge array structure

Coupled conditional nonlinear optimal perturbations and their application to ENSO ensemble forecasts

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Science China Earth Sciences 2024年第3期67卷 826-842页

作者： Wansuo DUAN Lei HU rong feng LASG Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China

Limitations are existed in current ensemble forecasting initial perturbation methods for describing the interactions among various spheres of the Earth system. In this study, a new method is proposed, namely, the coupled conditional nonlinear optimal perturbation(C-CNOP) method, which incorporates multisphere interactions much appropriately. The El Nino-Southern Oscillation(ENSO) is a typical ocean-atmosphere “coupling”(or “interaction”) phenomenon. The C-CNOP method is applied to ensemble forecasting of ENSO. It is demonstrated that the C-CNOP method can generate coupled initial perturbations(CPs) that appropriately consider initial ocean-atmosphere coupling uncertainty for ENSO ensemble forecasts. Results reveal that the CPs effectively improve the ability of ENSO ensemble-mean forecasts in both temporal variability of Nio3.4 sea surface temperature anomalies(SSTAs) and spatial variability of ENSO mature-phase SSTAs. Notably, despite the weakest ocean-atmosphere coupling strength in the tropical Pacific occurring during the boreal spring and summer, CPs still capture the uncertainties of this weak coupling when ENSO predictions are initialized at these seasons. This performance of CPs significantly suppresses the rapid increase of ENSO prediction errors due to the high ocean-atmosphere coupling instability during these seasons, and thus effectively extends the lead time of skillful ENSO forecasting. Hence, the C-CNOP method is a suitable initial perturbation approach for ENSO ensemble forecast that can describe initial ocean-atmosphere coupling uncertainty. It is expected that the CCNOP method plays a significant role in predictions of other high-impact climate phenomena, and even future Earth system predictions.

关键词： Ensemble forecast Multisphere interaction Initial perturbations ENSO

Ethylene promotes seed iron storage during Arabidopsis seed maturation via ERF95 transcription factor

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Journal of Integrative Plant Biology 2020年第8期62卷 1193-1212页

作者： Ying Sun Jia Qi Li Jing Ying Yan Jun Jie Yuan Gui Xin Li Yun rong Wu Ji Ming Xu rong feng huang Nicholas P.Harberd Zhong Jie Ding Shao Jian Zheng State Key Laboratory of Plant Physiology and Biochemistry College of Life SciencesZhejiang UniversityHangzhou 310058China Agricultural Experimental Station Zhejiang UniversityHangzhou 310058China College of Agronomy and Biotechnology Zhejiang UniversityHangzhou 310058China Biotechnology Research Institute Chinese Academy of Agricultural SciencesBeijing 100081China Department of Plant Science University of OxfordOxford OX13RBUnited Kingdom

Because Iron(Fe)is an essential element,Fe storage in plant seeds is necessary for seedling establishment following ***,the mechanisms controlling seed Fe storage during seed development remain largely *** we reveal that an ERF95 transcription factor regulates Arabidopsis seed Fe *** show that expression of ERF95 increases during seed maturation,and that lack of ERF95 reduces seed Fe accumulation,consequently increasing sensitivity to Fe deficiency during seedling ***,overexpression of ERF95 has the opposite *** show that lack of ERF95 decreases abundance of FER1 messenger RNA in developing seed,which encodes Fe-sequestering ***,a fer1-1 loss-of-function mutation confers reduced seed Fe accumulation,and suppresses ERF95-promoted seed Fe *** addition,ERF95 binds to specific FER1 promoter GCC-boxes and transactivates FER1 *** show that ERF95 expression in maturing seed is dependent on EIN3,the master transcriptional regulator of ethylene *** lack of EIN3 reduces seed Fe content,overexpression of ERF95 rescues Fe accumulation in the seed of ein3 loss-of-function ***,we show that ethylene production increases during seed *** conclude that ethylene promotes seed Fe accumulation during seed maturation via an EIN3-ERF95-FER1-dependent signaling pathway.

关键词： expression. ERF Arabidopsis

Self-Triggered Set Stabilization of Boolean Control Networks and Its Applications

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IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1631-1642页

作者： rong Zhao Jun-e feng Dawei Zhang the School of Mathematics Shandong UniversityShandong UniversityJinan 250100China

Set stabilization is one of the essential problems in engineering systems, and self-triggered control(STC) can save the storage space for interactive information, and can be successfully applied in networked control systems with limited communication resources. In this study, the set stabilization problem and STC design of Boolean control networks are investigated via the semi-tensor product technique. On the one hand, the largest control invariant subset is calculated in terms of the strongly connected components of the state transition graph, by which a graph-theoretical condition for set stabilization is derived. On the other hand, a characteristic function is exploited to determine the triggering mechanism and feasible controls. Based on this, the minimum-time and minimum-triggering open-loop, state-feedback and output-feedback STCs for set stabilization are designed,respectively. As classic applications of self-triggered set stabilization, self-triggered synchronization, self-triggered output tracking and self-triggered output regulation are discussed as well. Additionally, several practical examples are given to illustrate the effectiveness of theoretical results.

关键词： Boolean control networks(BCNs) output regulation self-triggered control semi-tensor product of matrices set stabilization synchronization

Response to climate changes in radial growth of Picea crassifolia in the Qilian mountains of northwestern China

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Forestry Studies in China 2013年第4期15卷 310-319页

作者： Jin-Mei XU Fu-Cheng BAO Jian-Xiong LV rong-feng huang You-Ke ZHAO Evans ROBERT Key Laboratory of Wood Science and Technology of State Forestry Administration Research Institute of Wood Industry Chinese Academy of Forestry CSIRO Materials Science and Engineering

In order to investigate the response to climate changes in radial growth of Picea crassifolia at the lower tree line in the middle Qilian mountains in northwestern China, relationships of standardized chronologies of annual ring, earlywood and latewood widths with mean monthly temperature and total monthly precipitation were analyzed by ways of correlation and pointer year analyses. The results show that annual ring, earlywood and latewood widths are significantly negatively correlated with mean monthly temperature in June and July. Annual ring and earlywood widths are significantly and positively correlated with total monthly precipitation in March, May and June and negatively correlated with total monthly precipitation in September. Latewood width is less sensitive to climate changes than the width of earlywood and insignificantly sensitive to precipitation. The results of pointer year analysis revealed that when summer temperatures are higher than the mean summer temperature synchronization and the summer precipitation lower than mean summer precipitation synchronization, narrow annual rings are formed. Wide annual rings are formed when summer temperatures are lower than the mean summer temperature synchronization and summer precipitation higher than mean summer precipitation synchronization. The results indicate that more precipitation in the spring and summer is helpful for radial growth while warmer summer restricts radial growth of P. crassifolia at the lower tree line in the middle Qilian mountains.

关键词： Qilian mountains ,Picea crassifolia annual ring width earlywood width latewood width ,response to climate change

Quantum phase transition of the Jaynes-Cummings model

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Science China(Physics,Mechanics & Astronomy) 2024年第1期67卷 1-9页

作者： Cheng Liu Jin-feng huang Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Key Laboratory for Matter Microstructure and Function of Hunan ProvinceDepartment of Physics and Synergetic Innovation Center for Quantum Effects and ApplicationsInstitute of Interdisciplinary StudiesHunan Normal UniversityChangsha 410081China

Herein,we propose an experimentally feasible scheme to show the quantum phase transition of the Jaynes-Cummings(JC)model by modulating the transition frequency of a two-level system in a quantum Rabi model with strong *** tuning the modulation frequency and amplitude,the ratio of the effective coupling strength of the rotating terms to the effective cavity(atomic transition)frequency can enter the deep-strong coupling regime,while the counter-rotating terms can be ***,a deep-strong JC model is *** ratio of the coupling strength to resonance frequencies in the deep-strong JC model is two orders of magnitude larger than the corresponding ratio in the original quantum Rabi *** scheme can be employed in atom-cavity resonance and off-resonance cases,and it is valid over a broad *** nonzero average cavity photons of the ground state indicate the emergence of a quantum phase ***,we demonstrate the dependence of the phase diagram on the atom-cavity detuning and modulation *** the parameters used in our scheme are within the reach of current experimental *** scheme provides a new mechanism for investigating the critical phenomena of finite-sized systems without requiring classical field limits,thereby opening a door for studying fundamental quantum phenomena occurring in the ultrastrong and even deep-strong coupling regimes.

关键词： Jaynes-Cummings model quantum phase transition frequency modulation

New quantification of symmetry energy from neutron skin thicknesses of^(48)Ca and^(208)Pb

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Nuclear Science and Techniques 2024年第10期35卷 188-196页

作者： rong An Shuai Sun Li-Gang Cao feng-Shou Zhang School of Physics Ningxia UniversityYinchuan 750021China Key Laboratory of Beam Technology of the Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Key Laboratory of Beam Technology of the Ministry of Education Institute of Radiation TechnologyBeijing Academy of Science and TechnologyBeijing 100875China Center of Theoretical Nuclear Physics National Laboratory of the Heavy Ion Accelerator of LanzhouLanzhou 730000China

Precise knowledge of the nuclear symmetry energy can be tentatively calibrated using multimessenger *** neutron skin thickness of a heavy nucleus is one of the most sensitive indicators for probing the isovector components of effective interactions in asymmetric nuclear *** studies have suggested that the experimental data from the CREX and PREX2 collaborations are not mutually compatible with existing nuclear *** this study,we review the quantification of the slope parameter of the symmetry energy L from the neutron skin thicknesses of^(48)Ca and^(208)*** energy density functionals classified by various isoscalar incompressibility coefficients K were employed to evaluate the bulk properties of finite *** calculated results suggest that the slope parameter L deduced from^(208)Pb is sensitive to the compression modulus of symmetric nuclear matter,but not that from^(48)*** effective parameter sets classified by K=220 MeV can provide an almost overlapping range of L from^(48)Ca and^(208)Pb.

关键词： Nuclear symmetry energy Neutron skin thickness Energy density functional

Dynamics of a Reaction-diffusion-ODE System in a Heterogeneous Media

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 275-301页

作者： Cong-hui ZHANG Hai-feng ZHANG Mei-rong ZHANG School of Science Beijing University of Civil Engineering and ArchitectureBeijing 102616China Institute of Applied System Analysis Jiangsu UniversityZhenjiang 212013China Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China

The existence and stability of stationary solutions for a reaction-diffusion-ODE system are investigated in this *** first show that there exist both continuous and discontinuous stationary *** a good understanding of the stability of discontinuous stationary solutions is gained under an appropriate *** addition,we demonstrate the influences of the diffusion coefficient on stationary *** results we obtained are based on the super-/sub-solution method and the generalized mountain pass ***,some numerical simulations are given to illustrate the theoretical results.

关键词： reaction-diffusion-ODE system discontinuous stationary solutions stability asymptotic behavior monotone solutions

A UNIFORM CONVERGENT PETROV-GALERKIN METHOD FOR A CLASS OF TURNING POINT PROBLEMS

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Journal of Computational Mathematics 2024年第5期42卷 1356-1379页

作者： Li feng Zhongyi huang Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China

In this paper,we propose a numerical method for turning point problems in one dimension based on Petrov-Galerkin finite element method(PGFEM).We first give a priori estimate for the turning point problem with a single boundary turning *** we use PGFEM to solve it,where test functions are the solutions to piecewise approximate dual *** prove that our method has a first-order convergence rate in both L∞h norm and a discrete energy norm when we select the exact solutions to dual problems as test *** results show that our scheme is efficient for turning point problems with different types of singularities,and the convergency coincides with our theoretical results.

关键词： Turning point problem Petrov-Galerkin finite element method Uniform convergency

Sequence [2,3]-Sigmatropic Rearrangement: One-Pot Synthesis of Proparggyl Allenylamines

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Chinese Journal of Chemistry 2024年第18期42卷 2223-2227页

作者： Huihui feng Yujuan Xie Lliang huang Yongqing Xu Junhai huang huangdi feng College of Chemistry and Chemical Engineering Shanghai University of Engineering ScienceShanghai 201620China Shanghai Frontiers Science Research Centerfor Druggability of Cardiovascular noncoding RNA Institute for Frontier Medical Technology Shanghai Universityof Engineering ScienceShanghai 201620China

Allenes,served as highly sought-after building blocks,are an indispensable component of synthetic *** utility in modulating the chemical,physical,and pharmaceutical properties of organic compounds make allenes a desirable choice in various ***,we report a facile method for the atom-economical synthesis of propargyl allenylamines via an underdeveloped[2,3]-sigmatropic *** strategy employs easily accessible propargylamines as starting materials,which are first converted into propargyl ammonium salts,followed by a base-promoted[2,3]-sigmatropic *** one-pot,two-step reaction proceeds in the absence of transition metals,displays a very broad scope,and does not require the introduction of the electron-withdrawing group into the starting materials.

关键词： Allene Propargylamine C-N activation Sigmatropic rearrangement Metal-free Synthetic methods Domino reactions