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Abnormal Site Preference of Al and Ga in Gd₃Al_2.3Ga_2.7O₁₂:Ce Crystals

PHYSICA STATUS SOLIDI B-BASIC SOLID STATE PHYSICS 2021年第8期258卷

作者： Li, Mingqing Meng, Meng Chen, Jie Sun, Yiyang Cheng, Guofeng Chen, Lu zhao, shuwen Wan, Bo Feng, He Ren, Guohao Ding, Dongzhou Chinese Acad Sci Shanghai Inst Ceram Shanghai 200050 Peoples R China Shanghai Univ Sch Mat Sci & Engn Shanghai 200444 Peoples R China

Large-sized Gd3Al2.3Ga2.7O12:Ce single crystals are grown by the Czochralski method. The distribution of Al and Ga at octahedral (oct-, 6-oxygen-coordinated) and tetrahedral (tet-, 4-oxygen-coordinated) sites in the crystal is studied. Rietveld refinement is used to analyze the site occupation of Al and Ga. The results show that Ga ions with a larger radius than Al ions prefer to occupy the more compact tetrahedral sites. Density functional theory calculations show that the energy for a Ga ion at the tetrahedral site is lower than that at the octahedral site in the Gd3Al5O12 crystal, whereas the case for Al occupation in the Gd3Ga5O12 crystal is opposite. Slater rules are used to estimate the effective charge number of different ions, and the distribution of coordination ions around the octahedral and tetrahedral sites is analyzed. Then, the interaction between ions is simplified and the repulsive energy between Al/Ga and the coordination ions is calculated, which could provide reasonable understanding on the abnormal occupation. In addition, the occupation of Sc in Gd/Y garnet systems is also discussed using this method.

关键词： cation occupation garnets scintillators single crystals

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Probing the Limit of the Number of Saturated Atoms for Achieving Hyperconjugative Aromaticity

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INORGANIC CHEMISTRY 2024年第30期63卷 14162-14170页

作者： Chen, shuwen Imran, Sajid zhao, Yu Zhu, Jun Xiamen Univ Coll Chem & Chem Engn State Key Lab Phys Chem Solid Surfaces Xiamen 361005 Peoples R China Xiamen Univ Coll Chem & Chem Engn Collaborat Innovat Ctr Chem Energy Mat iChEM Fujian Prov Key Lab Theoret & Computat Chem Xiamen 361005 Peoples R China Xiamen Univ Coll Chem & Chem Engn Dept Chem Xiamen 361005 Peoples R China Chinese Univ Hong Kong Sch Sci & Engn Shenzhen 518172 Guangdong Peoples R China

Aromaticity is a fundamental concept in organic chemistry. Hyperconjugative aromaticity, also known as hyperconjugation-induced aromaticity, has evolved from its origin from main group substituents to transition metal analogues, establishing itself as an important category of aromaticity. Additionally, aromatic compounds comprising two sp 3-carbon atoms have recently been reported both experimentally and computationally. However, what is the maximum number of sp 3-hybridized atoms needed to maintain hyperconjugative aromaticity? Here, we report that hyperconjugative aromaticity can be achieved in hexa-substituted indoliums and octa-substituted pyrroliums, possessing three-five sp 3-hybridized carbon/nitrogen atoms by means of density functional theory (DFT) calculations. The aromaticity was confirmed by using various aromaticity indices, i.e., NICS, MCI, and EDDB. Notably, the strong electron-donating ability and aurophilicity of Au(I) substituents play a pivotal role in maintaining the aromaticity and structural integrity. In addition, increasing the number of hyperconjugative centers will decrease the aromaticity in these five-membered rings. Our findings highlight the significance of transition metal substituents in hyperconjugative aromaticity and offer a novel approach for designing aromatic organometallics.

关键词： Atoms

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民营企业法治保障制度系统化建构研究

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保定学院学报 2021年第6期34卷 40-45页

作者：赵树文苏加彤河北大学法学院河北保定071002

民营企业是我国市场经济体系中最为活跃的微观主体,在国民经济发展中占据重要地位,并已成为当前经济改革深入推进的重要着力点,而良好的法治保障制度则是民营企业持续、健康发展的必须条件,否则借助民营企业来激发市场竞争效应的预期将... 详细信息

民营企业是我国市场经济体系中最为活跃的微观主体,在国民经济发展中占据重要地位,并已成为当前经济改革深入推进的重要着力点,而良好的法治保障制度则是民营企业持续、健康发展的必须条件,否则借助民营企业来激发市场竞争效应的预期将难以实现。为此,必须秉承系统思维,推进民营企业法治保障制度的系统化建构,注重对立法、执法与司法制度的整体性推进,以期有效地实现法治保障制度对推进民营企业发展所具有的政策促进功能、主体保障功能以及信心提升功能。所以,应以系统思维为指引,有针对性地推进我国民营企业法治保障制度的系统化建构。

关键词：民营企业法治保障系统论制度构建

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民营企业家刑事司法平等保障机制完善研究

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河北经贸大学学报（综合版） 2021年第2期21卷 63-71页

作者：赵树文安丽云宋雪河北大学法学院河北保定071002

强化民营企业家刑事司法平等保障机制建设是推进民营经济发展的重要条件,但是当前这一机制依然存在罪与非罪区分不清、强制措施适用不灵活、原罪问题处置不合理以及司法规则适用不平等等现象。这严重损害了民营企业家的合法权益,进而阻... 详细信息

强化民营企业家刑事司法平等保障机制建设是推进民营经济发展的重要条件,但是当前这一机制依然存在罪与非罪区分不清、强制措施适用不灵活、原罪问题处置不合理以及司法规则适用不平等等现象。这严重损害了民营企业家的合法权益,进而阻碍着民营企业与民营经济的发展。因此,应围绕着科学划分民刑案件界限、优化强制措施的使用机制,科学处理原罪问题、强化刑事司法平等理念等相关内容进行修正,以期进一步推进民营企业家刑事司法平等保障机制的完善,更好地保护民营企业家合法权益,并推进民营企业与民营经济的发展。

关键词：民营企业家刑事司法平等保障机制平等保护合法权益

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λ/20-Thick cavity for mimicking electromagnetically induced transparency at telecommunication wavelengths

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Advanced Photonics 2024年第3期6卷 42-50页

作者： Hua Lu Shouhao Shi Dikun Li shuwen Bo Jianxu zhao Dong Mao Jianlin zhao Northwestern Polytechnical University School of Physical Science and TechnologyMOE Key Laboratory of Material Physics and Chemistry under Extraordinary ConditionsKey Laboratory of Light-Field Manipulation and Information AcquisitionMinistry of Industry and Information TechnologyShaanxi Key Laboratory of Optical Information TechnologyXi’anChina

Optical cavities play crucial roles in enhanced light-matter interaction,light control,and optical communications,but their dimensions are limited by the material property and operating *** planar cavities are urgently in demand for large-area and integrated optical ***,extremely reducing the planar cavity dimension is a critical challenge,especially at telecommunication ***,we demonstrate a type of ultrathin cavities based on large-area grown Bi_(2)Te_(3)topological insulator(TI)nanofilms,which present distinct optical resonance in the near-infrared *** result shows that the Bi_(2)Te_(3)TI material presents ultrahigh refractive indices of>6 at telecommunication *** cavity thickness can approach 1/20 of the resonance wavelength,superior to those of planar cavities based on conventional Si and Ge high refractive index ***,we observed an analog of the electromagnetically induced transparency(EIT)effect at telecommunication wavelengths by depositing the cavity on a photonic *** EIT-like behavior is derived from the destructive interference coupling between the nanocavity resonance and Tamm *** spectral response depends on the nanocavity thickness,whose adjustment enables the generation of obvious Fano *** experiments agree well with the *** work will open a new door for ultrathin cavities and applications of TI materials in light control and devices.

关键词： topological insulator optical nanocavity photonic crystal electromagnetically induced transparency-like effect

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Clinicopathological characteristics and treatment of solid papillary carcinoma of the breast

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ASIAN JOURNAL OF SURGERY 2023年第8期46卷 3389-3390页

作者： zhao, Hua Lou, shuwen Yongkang Maternal & Child Hlth Care Hosp Dept Pathol 509 East Chengbei Rd Yongkang 321300 Zhejiang Peoples R China

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Provenance of a Stenian succession in the eastern Jiangnan(Sibao)Orogen,South China:Implications on tectonic affinity and pre-Neoproterozoic crustal evolution

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Geoscience Frontiers 2025年第2期16卷 19-35页

作者： Kai Wang Shuan-Hong Zhang shuwen Dong Qiqi Zhang Tianyu zhao Institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100081China Key Laboratory of Paleomagnetism and Tectonic Reconstruction Ministry of Natural ResourcesBeijing 100081China State Key Laboratory for Mineral Deposits Research Nanjing UniversityNanjing 210023China SinoProbe Center Chinese Academy of Geological SciencesBeijing 100037China State Key Laboratory of Geological Processes and Mineral Resources China University of GeosciencesWuhan 430074China

The Lower Tieshajie Subgroup at the conjunction zone of the Yangzte and Cathaysia blocks represents the only Stenian sedimentary succession in the eastern Jiangnan(Sibao)Orogen of South China,bearing important clues on plate boundary and pre-Neoproterozoic crustal *** report the first U-Pb and Hf isotopic data of detrital zircons from this succession to investigate the age and provenance *** and Hf isotopic compositions of detrital zircons from the lower and upper parts of the metamorphosed Lower Tieshajie Subgroup are *** are exclusively of magmatic origins,showing youngest age peaks at ca.1.17 Ga and ca.1.15 Ga,respectively,but both with a rarity of 1.12–1.10 Ga ages from the nearby magmatic *** constrains protolith deposition of the Lower Tieshajie Subgroup to be mainly at 1.17–1.12 Ga,while the timing of metamorphism is bracketed by the intruding unmetamorphosed granites to be 1.10–0.84 Ga,that is,related to Grenville-aged orogenesis at the Jiangnan *** detrital zircons yielded a broad age range of 3.28–1.03 Ga,dominated by a 1.20–1.10 Ga population interpreted to be sourced from coeval magmatic rocks within the Tieshajie Complex *** abundant Archean and Paleoproterozoic detrital zircons are well-matched with magmatic records from the Eastern Yangtze Block,suggesting a Yangtze Block affinity of the Lower Tieshajie *** implies that the surface boundary between the Yangtze and Cathaysia blocks is located to the south of the Lower Tieshajie Subgroup,probably in between the two parts of the Tieshajie *** peaks of detrital zircons at 2.85–2.78 Ga,2.68 Ga,and 2.50 Ga,combined with regional data,suggest episodic magmatism involved both crustal growth and reworking during the late Archean in the Jiangnan Orogen and adjacent areas of the Eastern Yangtze Block,while the 2.10–1.80 Ga peak corresponds to significant reworking of pre-existing crust related to the early assembly of the Nuna(Columbia)Superc

关键词： Provenance Late Mesoproterozoic Grenville-aged metamorphism Tectonic affinity Boundary between the Yangtze and Cathaysia blocks

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References Maxwell-based Permanent Magnet Synchronous Motor Short Circuit Faults and Electromagnetic Losses 3

References Maxwell-based Permanent Magnet Synchronous Motor ...

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3rd International Conference on Energy, Power and Electrical Technology, ICEPET 2024

作者： Wang, shuwen zhao, Aiming Shanghai Dianji University School of Electrical Engineering Shanghai China

ISBN: (纸本)9798350352658

Permanent magnet synchronous motor (PMSM) is a type of motor that is widely used in industrial production, possessing the high efficiency of permanent magnet motor and the precise control characteristics of synchronous motor. With the increase of the motor running time and the change of the external environment, it may lead to the damage of the insulation layer of the stator-side windings, resulting in the turn-to-turn short-circuit faults, which will have an adverse effect on the performance of the motor. In this paper, a 15KW water pump PMSM is selected, and the PMSM model is established by Ansys Maxwell finite element analysis software to study and analyse the relationship between stator side winding turn-to-turn short-circuit and electromagnetic loss, and compare the electromagnetic loss waveforms of the motor in normal operation and various turn-to-turn short-circuit conditions, and the analysis results show that the electromagnetic loss increases the most when the number of short-circuit turns is six. When the stator winding is short-circuited for five turns, the stator's iron consumption increases the most. In the case of a six-turn short circuit, the eddy current loss of the permanent magnet grows the most, and the copper consumption of the stator decreases the most. This provides a reference basis for motor short circuit fault diagnosis and preventive maintenance. © 2024 IEEE.

关键词： Stators

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Feature selection mechanism in CNNs for facial expression recognition 29

Feature selection mechanism in CNNs for facial expression re...

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29th British Machine Vision Conference, BMVC 2018

作者： zhao, shuwen Cai, Haibin Liu, Honghai Zhang, Jianhua Chen, Shengyong Zhejiang University of Technology Zhejiang China University of Portsmouth Portsmouth United Kingdom

Facial Expression Recognition (FER) has been a challenging problem in computer vision for many decades, mainly due to the high-level variation of face geometry and facial appearance. In this paper, we propose a feature selection network (FSN) to automatically extract and filter facial features by embedding a feature selection mechanism inside the AlexNet. The designed feature selection mechanism effectively filters irrelevant features and emphasises correlated features according to learned feature maps. Experiment results on several databases demonstrate that the FSN outperforms the AlexNet by a large margin and achieves comparable results with the state-of-the-art methods. Furthermore, the FSN also shows improved generalisation ability over the AlexNet in the cross validation experiment of different datasets. © 2018. The copyright of this document resides with its authors.

关键词： Feature Selection

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Polydopamine-linking coupling Ketjen black with graphene for anchoring palladium nanocrystallines enables a robust methanol oxidation

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INTERNATIONAL JOURNAL OF HYDROGEN ENERGY 2025年 100卷 149-155页

作者： Wulan, Qiqige Ma, Sizhuo zhao, Jinjuan Jin, Ruifa Li, shuwen Chifeng Univ Coll Chem & Life Sci Chifeng 024000 Peoples R China Lanzhou Univ Coll Chem & Chem Engn Lanzhou 730000 Peoples R China

Designing and developing superior associated supporting materials is a powerful strategy to improve the catalytic performance of the supported electrocatalyst for the methanol oxidation reaction (MOR). Herein, a new "surfaceclean" palladium nanocrystallines (Pd NCs) anchored on polydopamine (PDA)-linked tightly coupled Ketjen black (KB) and graphene nanosheets (GS) electrocatalyst (Pd/KB-PDA-GS) was prepared by self-polymerization reaction followed a simple surfactant-free wet chemical reduction strategy. As an electrocatalyst towards the alkaline MOR, the Pd/KB-PDA-GS exhibits a significantly boosted electrocatalytic behavior in terms of excellent mass/specific activity (1320.6 mA mg-1, 4.3 mA cm- 2), dependable long-term durability and forceful stability, remarkably surpassing to those of commercial Pd/C (533.1 mA mg-1, 3.4 mA cm- 2). The facts of electrochemical measurements and physicochemical analysis reveal that the polydopamine-linking plays a vital role in boosting electrocatalytic behavior of MOR. Briefly, after polydopamine-linking, the Pd/KB-PDA-GS is not only endowed rich hierarchical pore structures for mass transfer and more channels for electronic proton dual-coupled transfer, but also generated the sturdy metal-support interactions between Pd NCs and functional groups contained in polydopamine for firmly and evenly fixing small size Pd NCs on the KB-PDA-GS as well as optimizing the electronic state of Pd. Therefore, the strategy in this study will inspire the developing carbonaceous composite supporting materials by polydopamine-linking for the rational designing advanced electrocatalysts and beyond.

关键词： Graphene Ketjen black Metal-support interactions Methanol oxidation reaction Palladium nanocrystallines Polydopamine-linking

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