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ON POTENT ELEMENTS AND PSEUDO CLEAN RINGS

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数学杂志 2025年第1期45卷 39-47页

作者： ding Yan GAO Han-peng LIU Xin-yi YAN zi-yi ZHANG Ting School of Mathematical Sciences Anhui UniversityHefei 230601China

In this paper,potent index of an element and pseudo clean rings are *** properties and examples of pseudo clean rings are *** also show that Zm is pseudo clean for every 2≤m∈Z and pseudo clean rings are ***,we prove... 详细信息

关键词： clean rings strongly J-clean rings pseudo clean rings potent elements

A multi-parameter model of heat treatment process for soft magnetic materials on performance of HSERs

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Chinese Journal of Aeronautics 2022年第9期35卷 379-388页

作者： Jiaxin you Hao YU Huimin LIANG Yong XIE ding ding Department of Electrical Engineering Harbin Institute of TechnologyHarbin 150000China G&A Electronics Co. LtdGuilin 541000China

Abstract:Material properties play an important role in the performance of electromagnetic mechanism. For an aeronautic Hermetically-Sealed Electromagnetic Relay(HSER), more than 50%parts are made of soft magnetic materials. Therefore, the performance of soft magnetic materials directly determines the static and dynamic characteristics of the HSER. Based on the theory of crystal recrystallization, this paper analyzes cold extrusion and heat treatment in the processing of soft magnetic materials, simulates the grain change process of an armature at different heat treatment temperatures, establishes a correlation model of temperature, grain size, and magnetic energy,and verifies results by scanning electron microscopy. Results of heat treatment temperatures from 800 ℃to 920 ℃are obtained and compared. A sample soft magnetic material after heat treatment at different temperatures has the largest difference in the initial magnetization range, up to 22%. In order to verify the fluctuation of the overall output characteristics of an HSER caused by the difference between soft magnetic materials, a static and dynamic analysis model of a typical HSER is established, and the accuracy of the model is verified by a set of actual test system. The difference of dynamic characteristics under different heat treatment temperatures is nearly 3%.

关键词： Dynamic performance Heat treatment Hermetically-Sealed Electromagnetic Relay(HSER) Metallographic analysis Soft magnetic materials

数字公共性:数字乡村治理共同体的建构逻辑与优化路径

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西北农林科技大学学报（社会科学版） 2025年第1期25卷 10-16页

作者：丁波安徽大学社会与政治学院合肥230039

数字乡村建设以数字技术嵌入乡村社会,改变乡村社会的结构特征与治理模式,重构乡村治理共同体,形成具有数字公共性特征的数字乡村治理共同体。数字乡村治理共同体以数字主体、数字空间和数字场景的建构逻辑,培育数字参与理念、构建数字... 详细信息

数字乡村建设以数字技术嵌入乡村社会,改变乡村社会的结构特征与治理模式,重构乡村治理共同体,形成具有数字公共性特征的数字乡村治理共同体。数字乡村治理共同体以数字主体、数字空间和数字场景的建构逻辑,培育数字参与理念、构建数字联结纽带、搭建数字交往平台,实现数字公共性生产。数字乡村治理共同体通过治理主体的行动共建、治理方式的技术共治、治理资源的利益共享,推动乡村治理的数字赋权、数字赋能、数字赋利,有助于构建人人有责、人人尽责、人人享有的数字乡村治理共同体。

关键词：数字乡村建设数字公共性乡村治理数字乡村治理共同体

A generalization of Banach's lemma and its applications to perturbations of bounded linear operators

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Applied Mathematics(A Journal of Chinese Universities) 2024年第2期39卷 363-369页

作者： WANG zi ding Jiu WANG Yu-wen School of Mathematics Sciences Harbin Normal UniversityHarbin 150025China School of Mathematics and Natural Sciences The University of Southern MississippiHattiesburg MS 39406-5043USA Academic Committee Harbin Institute of PetroleumHarbin 150027China

Let X be a Banach space and let P:X→X be a bounded linear *** an algebraic inequality on the spectrum of P,we give a new sufficient condition that guarantees the existence of(I-P)^(-1) as a bounded linear operator on X,and a bound on its spectral radius is also *** generalizes the classic Banach *** apply the result to the perturbation analysis of general bounded linear operators on X with commutative perturbations.

关键词： Banach lemma spectral radius generalized inverse perturbation analysis

Modeling and control of a rigid-flexible coupling robot for narrow space manipulations

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Science China Technological Sciences 2025年

作者： Kuangda CHEN Huan ZHAO Jiexin ZHANG Mei FENG Yiwei WANG Jinliang WANG Han ding State Key Laboratory of Intelligent Manufacturing Equipment and Technology Huazhong University of Science and Technology Key Laboratory of CNC Equipment Reliability Ministry of Education Jilin University School of Medical Equipment Science and Engineering Huazhong University of Science and Technology

Narrow space manipulations are crucial for equipment maintenance, as they eliminate the need for disassembly, thus reducing costs and increasing efficiency. Cable-driven flexible robots possess exceptional capabilities in maneuvering through narrow spaces, thanks to their interaction compliance and distal dexterity. However, their inherent low stiffness causes a decline in the location accuracy of the robot and could even lead to manipulation failure. To address this challenge, this paper proposes a novel type of rigid-flexible coupling robot, which increases the stiffness of the robot while ensuring the reachability within a narrow space. To achieve high-accuracy location in a narrow space, kinematic and control methods are proposed. Specifically,the robot forward kinematics are uniformly represented, and the closed-form inverse kinematics solution is derived. Furthermore, in cases where the robot?s structure fails to align with Pieper?s solution, a two-stage search strategy is utilized to solve the inverse kinematics, resulting in a high success rate of 99.1%. Based on the proposed kinematics, a rigid-dominated control method is then proposed to facilitate localization and pose alignment of target objects in narrow spaces. The practical comparative experiments show that the proposed robot has the capability of high accuracy control in narrow spaces.

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Holographic Schwinger effect in a soft wall AdS/QCD model

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Chinese Physics C 2021年第1期45卷 127-132页

作者： Yue ding zi-qiang Zhang School of Mathematics and Physics China University of GeosciencesWuhan 430074China

We perform a potential analysis for the holographic Schwinger effect in a deformed AdS5 model with conformal invariance broken by a background *** evaluated the static potential by analyzing the classical action of a string attached to a rectangular Wilson loop on a probe D3 brane located at an intermediate position in the bulk AdS *** observed that the inclusion of the chemical potential tends to enhance the production rate,which is opposite to the effect of the confining *** addition,we calculated the critical electric field based on the Dirac-Born-Infeld(DBI)action.

关键词： AdS/CFT correspondence gauge-gravity duality holographic Schwinger effect

我们都是“同时代人”——如何建构当代文学价值共同体的反思

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当代文坛 2025年第1期 77-81页

作者：丁帆南京大学文学院

“同时代人”是一个超越年龄、时空的广义内涵的存在,它打破了生理年龄和朝代更迭,以代际划分的“同时代人”的陈见,用一种具有深刻和前瞻意义的理念,聚合成一种具有“当代性”的切分方法,以跨越代际的共同价值观来重塑“同时代人”群体... 详细信息

“同时代人”是一个超越年龄、时空的广义内涵的存在,它打破了生理年龄和朝代更迭,以代际划分的“同时代人”的陈见,用一种具有深刻和前瞻意义的理念,聚合成一种具有“当代性”的切分方法,以跨越代际的共同价值观来重塑“同时代人”群体,以此作为解决创作困囿和批评迷惘的突破口。“我们可以使自己成为这些文本的同时代人”的命题,才是需要正视的最本质的问题所在。当下的“同时代人”,既要以史为鉴,从历史的“同时代人”的思想宝库中,汲取属于我们这个时代的相对统一价值观,同时还要引领更多能够聚合在同一价值观下的“同时代人”,发出对整个世界的批判性哲学诘问,这也是改“未完成的现代性”为“当代性”关键词的理由,希冀由此而触及对当代文学治史观念的一种新观念和新方法,在“同时代人”旗帜下,建构起一种基本的人文价值观和学术守则。

关键词： “同时代人” “当代性” 文学价值共同体 “真理性”

Quantum simulation of molecular interaction and dynamics at surfaces

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Frontiers of physics 2011年第3期6卷 294-308页

作者： zi-jing ding Yang JIAO Sheng MENG Beijing National Laboratory for Condensed Matter Physics and Institute of Physics Chinese Academy of Sciences Beijing 100190 China

The interaction between molecules and solid surfaces plays important roles in various applications, including catalysis, sensors, nanoelectronies, and solar cells. Surprisingly, a full understanding of molecule-surface interaction at the quantum mechanical level has not been achieved even for very simple molecules, such as water. In this mini-review, we report recent progresses and current status of studies on interaction between representative molecules and surfaces. Taking water/metal, DNA bases/carbon nanotube, and organic dye molecule/oxide as examples, we focus on the understanding on the microstructure, electronic property, and electron-ion dynamics involved in these systems obtained from first-principles quantum mechanical calculations. We find that a quantum mechanical description of molecule surface interaction is essential for understanding interface phenomenon at the microscopic level, such as wetting. New theoretical developments, including van der Waals density functional and quantum nuclei treatment, improve further our understanding of surface interactions.

关键词： adsorption quantum simulation density functional theory electronic structure electrondynamics

Effect of Preparation Methods of Bi_(2)O_(3) Nanoparticles on their Photocatalytic Activity

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Chemical Research in Chinese Universities 2004年第6期20卷 717-721页

作者： ding Peng DU Yao-guo XU zi-li Department of Environment Science College of Environment and ResourcesJilin UniversityChangchun 130023P.R.China Department of Chemistry Changchun Normal CollegeChangchun 130032P.R.China

Bi 2O 3 nanoparticles were prepared by means of ammonia precipitation, polyol mediated methods and microemulsion chemical method. The structure and properties of the as-prepared nanoparticles, having been submitted to a heat-treatment test at 750 ℃, were characterized by means of XRD, BET, XPS and UV-Vis absorption techniques. The photocatalytic oxidation reactions of benzene, toluene and xylene were used as the model reaction to measure the photocatalytic activity of Bi 2O 3 nanoparticles, respectively. The results show that the crystallite size of Bi 2O 3 prepared with different methods and calcined at 750 ℃ were 50.6, 38.5 and 31.5 nm, respectively. The photocatalytic activity of Bi 2O 3 nanoparticles prepared with the microemulsion chemical method was higher than that of the particles prepared with the polyol mediated method; and that of the particles prepared with the micromulsion chemical method was the highest among the three. The degradation rates of the three pollutants xylene, toluene and benzene decreased in sequence.

关键词： Bi_(2)O_(3) Preparation method Characterization Photocatalytic activity