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Observation of acoustic hybrid topological phases induced by the p-d orbital interactions

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 132-139页

作者： Xiao Xiang Feng Gao Yu-gui Peng Peng Wu Zong-Lin Li Xue-Feng Zhu School of Physics and Innovation Institute Huazhong University of Science and Technology

In spinless systems,growing attention has recently been attracted to synthetic gauge fields,which redefine the fundamental crystal symmetries by utilizing the projective algebraic ***,synthetic gauge fields have been commonly investigated in single orbital systems,and explorations on hybrid orbitals remain elusive in ***,we report the experimental observation of hybrid topological phases induced by hybrid synthetic gauge flux,which is formed by the interaction between p and d orbitals embedded in acoustic *** breaking the translation symmetries of Lxand/or Ly,we unambiguously demonstrate the first-order M?bius edge states and higher-order corner *** work establishes a platform for seeking exotic topological phases induced by hybrid-orbitals interactions and initializing the framework of hybrid-orbitalsrelated topological *** applications can be anticipated in scenarios such as high-quality sensing and robust wave trapping due to the stepwise energy distribution of the hybrid topological phase.

关键词： topological insulator synthetic gauge field projective symmetry corner states

书信交往与苏门的发展历程——以苏轼与四学士为中心

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海南大学学报（人文社会科学版） 2025年第1期43卷 16-25页

作者：李贵王兴武上海师范大学人文学院上海200234

由苏轼主盟的“苏门”在哲宗元祐年间大放异彩,是两宋影响最大的文学群体之一。在长达四十三年的时间里,书信是苏轼与“四学士”等人最主要的交往媒介。这些书信在苏门的发展历程中发挥了不可替代的重要作用。苏门文人在书信中求教讨论... 详细信息

由苏轼主盟的“苏门”在哲宗元祐年间大放异彩,是两宋影响最大的文学群体之一。在长达四十三年的时间里,书信是苏轼与“四学士”等人最主要的交往媒介。这些书信在苏门的发展历程中发挥了不可替代的重要作用。苏门文人在书信中求教讨论、品题称扬、交流信息、劝勉慰藉、宣泄情感、传承斯文,在此过程中建构起集体认同,培养了深厚情谊,写下了传世佳作。苏轼和四学士的来往书信,在平易自然的表达中见出作者们真实的情感和隐秘的心迹,在温暖的人际关系中见出人性的真善美,具有高度的文学价值和史学价值。探讨苏门书信交往的细节和意义,有助于深化对宋代文学史和社会文化史的认识。

关键词：苏门苏轼苏门四学士书信交往

Analgesic effects of JCM-16021 on neonatal maternal separation-induced visceral pain in rats

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World Journal of Gastroenterology 2010年第7期16卷 837-845页

作者： Joseph jy Sung Faculty of Medicine The Chinese University of Hong Kong

AIM:To investigate the pharmacological effect of JCM-16021,a Chinese herbal formula,and its underlying ***:JCM-16021 is composed of seven herbal plant *** raw materials of the formula were examined according to the quality control criteria listed in the Chinese Pharmacopeia(2005).In a neonatal maternal separation(NMS)model,male SpragueDawley rats were submitted to daily maternal separation from postnatal day 2 to day 14,or no specific handling(NH).Starting from postnatal day 60,rats were administered JCM-16021(2,4,8 g/kg per day)orally twice a day for 28 *** threshold pressure and electromyographic activities of external oblique muscles in response to colorectal distention recorded with a Power Lab System(AD Instruments International),were tested as pain *** in serotonin(5-HT)and 5-hydroxyindoleacetic acid(5-HIAA)concentrations in the colon of rats were analyzed;the enterochromaffin cell numbers and serotonin transporter in the colon of rats were also evaluated with an immunohistochemistry ***:NMS treatment significantly reduced pain threshold pressure(37.4±1.4 mmHg),as compared to that of NH rats(57.7±1.9 mmHg,P<0.05).After JCM-16021 treatment,the pain threshold pressure significantly increased when compared to that before treatment(34.2±0.9 mmHg vs 52.8±2.3 mmHg in the high dose group,40.2±1.6 mmHg vs 46.5±1.3 mmHg in the middle dose group,and 39.3±0.7 mmHg vs 46.5±1.6 mmHg in the low dose group,P<0.05).Also JCM-16021 significantly and dose-dependently decreased electromyographic activity to the graded colorectal distension(CRD),(the meanΔAUC values were:0.17±0.03,0.53±0.15,1.06±0.18,1.22±0.24 in the high dose group;0.23±0.04,0.68±0.17,1.27 ±0.26,1.8±0.3 in the middle dose group;and 0.29 ±0.06,0.8±0.16,1.53±0.24,2.1±0.21 in the low dose group for the pressures 20,40,60,80 mmHg),as compared to the NMS vehicle *** meanΔAUC values were:0.57±0.12,1.33±0.18,2.57±0.37,3.08±0.37 for the pressures 20,40,60,80 mmHg(P

关键词： Analgesia effect Neonatal maternal separation Visceral hyperalgesia Herbal medicine Serotonin pathway

Electron Microscopy Studies on Ultrafine Zirconia Powders from Solvent Extraction with Tributyl Phosphate in Kerosene

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Journal of Materials Science & Technology 1995年第3期11卷 217-221页

作者： YANG, CF CHEN, jy Inst of Chemical Metallurgy Chinese Acad of Sciences Beijing China

Solvent extraction of Zr(IV) with TBP in kerosene was used to precipitate precursory zirconia which was then processed to produce ultrafine zirconia powders. The powder prepared was examined and characterized with transmission electron microscopy (TEM) and X-ray diffraction (XRD). Effects of the conditions of preparation on powder properties were especially investigated. It was found the precipitate was, gel-like material with heterogeneous porosity. The gel transformed to polycrystalline particles when calcined to ultrafine powder at 600 degrees C. The composition of the loaded organic phase and the conditions of washing the precipitate are two main factors affecting the properties of powder obtained.

关键词： Zirconia

Supersonic flow onto solid wedges, multidimensional shock waves and free boundary problems Dedicated to Professor LI Ta Tsien on the Occasion of His 80th Birthday

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Science China Mathematics 2017年第8期60卷 1353-1370页

作者： CHEN gui-Qiang School of Mathematical Sciences Fudan University Academy of Mathematics and Systems Science Chinese Academy of Sciences School of Mathematical Sciences University of Chinese Academy of Sciences Mathematical Institute University of Oxford

When an upstream steady uniform supersonic flow impinges onto a symmetric straight-sided wedge,governed by the Euler equations,there are two possible steady oblique shock configurations if the wedge angle is less than the detachment angle—the steady weak shock with supersonic or subsonic downstream flow(determined by the wedge angle that is less than or greater than the sonic angle)and the steady strong shock with subsonic downstream flow,both of which satisfy the entropy *** fundamental issue—whether one or both of the steady weak and strong shocks are physically admissible solutions—has been vigorously debated over the past eight *** this paper,we survey some recent developments on the stability analysis of the steady shock solutions in both the steady and dynamic *** the static stability,we first show how the stability problem can be formulated as an initial-boundary value type problem and then reformulate it into a free boundary problem when the perturbation of both the upstream steady supersonic flow and the wedge boundary are suitably regular and small,and we finally present some recent results on the static stability of the steady supersonic and transonic *** the dynamic stability for potential flow,we first show how the stability problem can be formulated as an initial-boundary value problem and then use the self-similarity of the problem to reduce it into a boundary value problem and further reformulate it into a free boundary problem,and we finally survey some recent developments in solving this free boundary problem for the existence of the PrandtlMeyer configurations that tend to the steady weak supersonic or transonic oblique shock solutions as time goes to *** further developments and mathematical challenges in this direction are also discussed.

关键词： shock wave free boundary wedge problem transonic mixed type Euler equations static stability dynamic stability

The smoothed finite element method (S-FEM):A framework for the design of numerical models for desired solutions

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Frontiers of Structural and Civil Engineering 2019年第2期13卷 456-477页

作者： gui-Rong Liu Department of Aerospace Engineering and Engineering Mechanics University of CincinnatiCincinnati 45219USA

The smoothed finite element method (S-FEM) was originated by G R Liu by combining some meshfree techniques with the well-established standard finite element method (FEM). It has a family of models carefully designed with innovative types of smoothing domains. These models are found having a number of important and theoretically profound properties. This article first provides a concise and easy-to-follow presentation of key formulations used in the S-FEM. A number of important properties and unique features of S-FEM models are discussed in detail, including 1) theoretically proven softening effects;2) upper-bound solutions;3) accurate solutions and higher convergence rates;4) insensitivity to mesh distortion;5) Jacobian?free;6) volumetric-locking-free;and most importantly 7) working well with triangular and tetrahedral meshes that can be automatically generated. The S-FEM is thus ideal for automation in computations and adaptive analyses, and hence has profound impact on Al-assisted modeling and simulation. Most importantly, one can now purposely design an S-FEM model to obtain solutions with special properties as wish, meaning that S-FEM offers a framework for design numerical models with desired properties. This novel concept of numerical model demand may drastically change the landscape of modeling and simulation. Future directions of research are also provided.

关键词： computational method finite element method smoothed finite element method strain smoothing technique smoothing domain weakened weak form solid mechanics softening effect upper bound solution

Numerical modeling of an advancing hydraulically-driven pile in sand

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第1期12卷 15-23页

作者： Meen-wah gui Department of Civil Engineering National Taipei University of Technology

The penetration of a model pile through sand was investigated via a numerical analysis. Data from nine triaxial compression tests on dense specimens at different stress levels was generalized and used to create an empirical non-linear plastic hardening stress-strain relation for use in the analysis. As the computer program used is capable of large displacement analyses in radial symmetry, we expected that the analysis would easily reproduce the tip resistance penetration profile of the model pile in sand of known density and stress. However, initial attempts led to over-prediction. Successful analyses required both successive reformations of the mesh and the complete elimination of the dilatant peak in soil strength, which is naturally eliminated under large confining stress directly beneath the advancing tip, and that soil in the far-field had strained insufficiently to reach peak strength. Thus, the soil around the shaft must have been sheared to a critical state as it flowed past the tip. The hypothesis that the resistance to displacement piles in sand is mainly a function of the deformability of the sand was again proven, and the use of peak strength in the traditional bearing capacity formulae was found to be inappropriate. Independent investigation in this direction is needed to quantify the hypothesis.

关键词： Hydraulic pile Tip resistance Sand Double yield (DY) model Pile penetration Grid re-meshing

Efficient photocatalytic reduction of CO2 to formate by a molecular noble metal-free system

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Science China Chemistry 2025年第01期 152-156页

作者： Lihua Zhang Lingjing Chen Huatian Shi Yue Wei gui Chen Tai-Chu Lau School of Environment and Civil Engineering Research Center for Eco-environmental Engineering Dongguan University of Technology Department of Chemistry and Institute of Molecular Functional Materials City University of Hong Kong

Reducing CO2to carbon-neutral solar fuels can not only alleviate the energy demand but also mitigate the greenhouse *** present,developing an efficient non-noble metal photo/electrocatalytic system for converting CO2to a specific product beyond CO is still a big ***,we report a new cobalt complex bearing 2,2′-bi-1,10-phenanthroline ligand that can photocatalytically reduce CO2to formate （HCOO-）.Turnover number （TON） for HCOO-up to 677 with 99%selectivity can be achieved using organic dyes purpurin as photosensitizer and 1,3-dimethyl-2-phenyl-2,3-dihydro-1H-benzo[d]imidazole （BIH） as sacrificial reductant in a CO2-saturated NMP/TEA （v/v,3:1） solution under visible light *** potential electrolysis at-1.41 V （***/Ag Cl） in the presence of 12 m M Et3NHBF4also produced HCOO-with Faradaic efficiency of 39%.Spectroscopic and electrochemical studies suggest that a[CoI-H]species is the key intermediate for CO2reduction.

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A Survey on Pre-Processing in Image Matting

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Journal of Computer Science & Technology 2017年第1期32卷 122-138页

作者： gui-Lin Yao School of Computer and Information Engineering Harbin University of Commerce Harbin 150028 China

Pre-processing is an important step in digital image matting, which aims to classify more accurate foreground and background pixels from the unknown region of the input three-region mask （Trimap）. This step has no relation with the well-known matting equation and only compares color differences between the current unknown pixel and those known pixels. These newly classified pure pixels are then fed to the matting process as samples to improve the quality of the final matte. However, in the research field of image matting, the importance of pre-processing step is still blurry. Moreover, there are no corresponding review articles for this step, and the quantitative comparison of Trimap and alpha mattes after this step still remains unsolved. In this paper, the necessity and the importance of pre-processing step in image matting are firstly discussed in details. Next, current pre-processing methods are introduced by using the following two categories： static thresholding methods and dynamic thresholding methods. Analyses and experimental results show that static thresholding methods, especially the most popular iterative method, can make accurate pixel classifications in those general Trimaps with relatively fewer unknown pixels. However, in a much larger Trimap, there methods are limited by the conservative color and spatial thresholds. In contrast, dynamic thresholding methods can make much aggressive classifications on much difficult cases, but still strongly suffer from noises and false classifications. In addition, the sharp boundary detector is further discussed as a prior of pure pixels. Finally, summaries and a more effective approach are presented for pre-processing compared with the existing methods.

关键词： image matting pixel classification pre-processing Trimap expansion