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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

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

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

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

Dark Matter Search in Dwarf Irregular Galaxies with Ten Years of Data from the Ice Cube Neutrino Observatory

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Research in Astronomy and Astrophysics 2024年第3期24卷 75-82页

作者： Yi-Fei Lü Ben-Yang Zhu rong-Lan Li Xue-Kang Guo Tian-Ci Liu Yong-Bo huang Yun-feng Liang Guangxi Key Laboratory for Relativistic AstrophysicsSchool of Physical Science and TechnologyGuangxi University Nanning 530004China

Dwarf irregular galaxies(dIrrs),as rotationally supported systems,have more reliable J-factor measurements than dwarf spheroidal galaxies and have received attention as targets for dark matter detection in recent *** this paper,we use 10 yr of IceCube muon-track data and an unbinned maximum-likelihood-ratio method to search for neutrino signals beyond the background from the directions of seven dIrrs,aiming to detect neutrinos produced by heavy annihilation dark *** do not detect any significant *** on such null results,we calculate the upper limits on the velocity-averaged annihilation cross section for 1 TeV–10 PeV dark *** limits,although weaker than the strictest constraints in the literature in this mass range,are also a good complement to the existing results considering the more reliable J-factor measurements of dIrrs.

关键词： (cosmology) dark matter-cosmology theory-galaxies dwarf

Earth's core-mantle boundary shaped by the crystallization of a hydrous terrestrial magma ocean

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National Science Review 2024年第7期11卷 73-75页

作者： Qingyang Hu Jie Deng Yukai Zhuang Zhenzhong Yang rong huang Center for High Pressure Science and Technology Advanced Research(HPSTAR) Shanghai Advanced Research in Physical Sciences(SHARPS) Department of Geosciences Princeton University Institute of Atomic and Molecular Physics Sichuan University Key Laboratory of Polar Materials and Devices Department of Electronics East China Normal University

A water-rich global magma ocean(MO)likely existed in the early Hadean eon and subsequently cooled and *** water is an oxidant and is known to fundamentally affect liquid crystallization, the role of primordial water d... 详细信息

关键词： CROSSOVER MELT

A Deep Model for Partial Multi-label Image Classification with Curriculum-based Disambiguation

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Machine Intelligence Research 2024年第4期21卷 801-814页

作者： feng Sun Ming-Kun Xie Sheng-Jun huang MIIT Key Laboratory of Pattern Analysis and Machine Intelligence College of Computer Science and TechnologyNanjing University of AeronauticsandAstronauticsNanjing211106China

In this paper,we study the partial multi-label(PML)image classification problem,where each image is annotated with a candidate label set consisting of multiple relevant labels and other noisy *** PML methods typically design a disambiguation strategy to filter out noisy labels by utilizing prior knowledge with extra assumptions,which unfortunately is unavailable in many real ***,because the objective function for disambiguation is usually elaborately designed on the whole training set,it can hardly be optimized in a deep model with stochastic gradient descent(SGD)on *** this paper,for the first time,we propose a deep model for PML to enhance the representation and discrimination *** the one hand,we propose a novel curriculum-based disambiguation strategy to progressively identify ground-truth labels by incorporating the varied difficulties of different *** the other hand,consistency regularization is introduced for model training to balance fitting identified easy labels and exploiting potential relevant *** experimental results on the commonly used benchmark datasets show that the proposed method significantlyoutperforms the SOTA methods.

关键词： Partial multi-label image classification curriculum-based disambiguation consistency regularization label difficulty candidatelabel set.

WeldNet:A voxel-based deep learning network for point cloud annular weld seam detection

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Science China(Technological Sciences) 2024年第4期67卷 1215-1225页

作者： WANG Hui rong YouMin XU JiaJun XIANG SongMing PENG YiFan huang Yu State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and TechnologyWuhan 430074China School of Mechanical Science and Engineering Huazhong University of Science and TechnologyWuhan 430074China

Weld seam detection is an important part of automated *** present,few studies have been conducted on annular weld seams,and a lot of defects exist in the point cloud model of the tube sheet obtained by RGB-D cameras and photography *** at the above problems,this paper proposed an annular weld seam detection network named WeldNet where a voxel feature encoding layer was adaptively improved for annular weld seams,the sparse convolutional network and region proposal network(RPN)were used to detect annular weld seam position,and an annular weld seam detection loss function was ***,an annular weld seam dataset was established to train the *** with the random sampling consistency(RANSAC)method,WeldNet has a higher detection accuracy,as well as a higher detection success rate which has increased by 23%.Compared with U-Net,WeldNet has been proven to achieve a better detection result,and the intersection over the union of the weld seam detection is improved by 17.8%.

关键词： deep learning point cloud weld seam detection welding annular weld seam