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Journal of Mountain Science 2024年第8期21卷 2844-2854页

作者： CHEN Wenhua xiang tian School of Civil Engineering Beijing Jiaotong UniversityBeijing 202303China

Water freezing in rock fractures causes volumetric expansion and fracture development through frost *** study introduces a novel analytical model to investigate how uneven freezing force and surrounding rock pressure influence fracture initiation,based on mass conservation,elasticity,and water-ice phase transition principles.A model for rock fracture initiation considering freezing temperature,uneven freezing expansion,in-situ stress,and lateral pressure was proposed based on fracture *** for stress intensity factors were developed and validated using the phase field *** effects of rock elastic modulus anisotropy and critical fracture energy density on fracture initiation were also *** results show that the values of KI and KII exhibit an upward trend as the freezing temperature,uneven expansion,in-situ stress,and lateral pressure *** uneven freezing expansion has the most significant influence on KI and KII values among these *** the uneven freezing expansion coefficient increases to 0.5,the fracture initiation mode shifts from tensile fracture to shear *** the lateral pressure coefficient increases to 1,the fracture initiation mode shifts from tensile fracture to shear *** elastic modulus anisotropy causes fractures to propagate in a clockwise direction,forming a'butterfly'*** fracture energy density an isotropy causes counterclockwise deviation in propagation direction,resulting in branching paths and an'H'-shaped pattern.

关键词： Rock fractures Fracture water Uneven freezing expansion Phase field method Initiation angle Anisotropy

Quantum weak force sensing with squeezed magnomechanics

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Science China(Physics,Mechanics & Astronomy) 2024年第10期67卷 23-32页

作者： Qian Zhang Jie Wang tian-xiang Lu Ran Huang Franco Nori Hui Jing Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Department of Physics and Synergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal UniversityChangsha 410081China Theoretical Quantum Physics Laboratory Cluster for Pioneering ResearchRIKENWako-shi 351-0198Japan Center for Quantum Computing RIKENWako-shi 351-0198Japan Department of Physics University of MichiganAnn Arbor 48109-1040USA College of Physics and Electronic Information Gannan Normal UniversityGanzhou 341000China Academy for Quantum Science and Technology Zhengzhou University of Light IndustryZhengzhou 450002China

Cavity magnomechanics,exhibiting remarkable experimental tunability,rich magnonic nonlinearities,and compatibility with various quantum systems,has witnessed considerable advances in recent ***,the potential benefits of using cavity magnomechanical(CMM)systems in further improving the performance of quantum-enhanced sensing for weak forces remain largely *** we show that,by squeezing the magnons,the performance of a quantum CMM sensor can be significantly enhanced beyond the standard quantum limit(SQL).We find that,for comparable parameters,two orders of magnitude enhancement in the force sensitivity can be achieved in comparison with the case without magnon ***,we obtain the optimal parameter regimes of homodyne angle for minimizing the added quantum *** findings provide a promising approach for highly tunable and compatible quantum force sensing using hybrid CMM devices,with potential applications ranging from quantum precision measurements to quantum information processing.

关键词： quantum force sensing cavity magnomechanics magnon Kerr effect

Quantum squeezing induced nonreciprocal phonon laser

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 20-30页

作者： tian-xiang Lu Yan Wang Keyu Xia Xing Xiao Le-Man Kuang Hui Jing College of Physics and Electronic Information Gannan Normal UniversityGanzhou 341000China Key Laboratory of Low-Dimensional Quantum Structures and Quantum Control of Ministry of Education Department of Physics and Synergetic Innovation Center for Quantum Effects and ApplicationsHunan Normal UniversityChangsha 410081China Academy for Quantum Science and Technology Zhengzhou University of Light IndustryZhengzhou 450002China College of Engineering and Applied Sciences National Laboratory of Solid State Microstructuresand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210023China

Phonon lasers or coherent amplifications of mechanical oscillations are powerful tools for fundamental studies on coherent acoustics and hold potential for diverse applications,ranging from ultrasensitive force sensing to phononic information ***,we propose the use of an optomechanical resonator coupled to a nonlinear optical resonator for directional phonon *** find that by pumping the nonlinear optical resonator,directional optical squeezing can occur along the pump *** a result,we can achieve the directional mechanical gain using directional optical squeezing,thereby leading to nonreciprocal phonon lasing with a well-tunable directional power *** work proposes a feasible way to build nonreciprocal phonon lasers with various nonlinear optical media,which are important for a wide range of applications,such as directional acoustic amplifiers,invisible sound sensing or imaging,and one-way phononic networks.

关键词： nonreciprocal phonon laser directional quantum squeezing optomechanics

A Review of Type 1 and Type 2 Intraductal Papillary Neoplasms of the Bile Duct

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Current Medical Science 2024年第3期44卷 485-493页

作者： Xia-hui HUANG tian-xiang CHEN Hong-liang LIU Ming-wen HUANG Department of General Surgery The Second Affiliated Hospital of Nanchang UniversityNanchang330006China

Intraductal papillary neoplasm of the bile duct(IPNB)is a heterogeneous disease similar to intraductal papillary mucinous neoplasm of the *** lesions have been recognized as one of the three major precancerous lesions in the biliary tract since *** 2018,Japanese and Korean pathologists reached a consensus,classifying IPNBs into type l and type 2 *** are more prevalent in male patients in East Asia and are closely related to diseases such as cholelithiasis and *** a molecular genetic perspective,IPNBs exhibit early genetic variations,and different molecular pathways may be involved in the tumorigenesis of type 1 and type 2 *** histological subtypes of IPNBs include gastric,intestinal,pancreaticobiliary,or oncocytic subtypes,but type 1 IPNBs typically exhibit more regular and well-organized histological features than type 2 IPNBs and are more commonly found in the intrahepatic bile ducts with abundant *** to the rarity of these lesions and the absence of specific clinical and laboratory features,imaging is crucial for the preoperative diagnosis of IPNB,with local bile duct dilation and growth along the bile ducts being the main imaging *** resection remains the optimal treatment for IPNBs,but negative bile duct margins and the removal of lymph nodes in the hepatic hilum significantly improve the postoperative survival rates for patients with IPNBs.

关键词： intraductal papillary neoplasm of the bile duct subclassification neoplasms precancerous tissue prognosis

Addison's disease caused by adrenal tuberculosis may lead to misdiagnosis of major depressive disorder: A case report

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World Journal of Clinical Cases 2024年第1期12卷 217-223页

作者： tian-xiang Zhang Hong-Yan Xu Wei Ma Jian-Bao Zheng Department of Tuberculosis The Tuberculosis Hospital of Shaanxi ProvinceXi’an 710100Shaanxi ProvinceChina Department of General Surgery First Affiliated Hospital of Xi’an Jiaotong UniversityXi’an 710061Shaanxi ProvinceChina

BACKGROUND Addison’s disease(AD)is a rare but potentially fatal disease in Western countries,which can easily be misdiagnosed at an early *** adrenal tuberculosis(TB)may lead to depression in *** SUMMARY We report a case of primary adrenal insufficiency secondary to adrenal TB with TB in the lungs and skin in a 48-year-old *** patient was misdiagnosed with depression because of her depressed *** had hyperpigmentation of the skin,nails,mouth,and *** final diagnosis was adrenal TB that resulted in the insufficient secretion of adrenocortical *** hormone test,skin biopsy,T cell spot test of TB,and adrenal computed tomography scan were used to confirm the *** patient’s condition improved after hormone replacement therapy and TB *** Given the current status of TB in high-burden countries,outpatient doctors should be aware of and pay attention to TB and understand the early symptoms of AD.

关键词： Primary adrenal insufficiency Adrenal tuberculosis Fatigue Hypotension Hyperkalemia Hyponatremia Depression Case report

The Active Compensation Technique for Large Reflector Antennas Based on Quadratic Curve Fitting

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Research in Astronomy and Astrophysics 2024年第7期24卷 226-234页

作者： tian-xiang Zheng Bin-Bin xiang Han-Wei Cui Wei Wang Pei-Yuan Lian Shang-Ming Lin Yang Zhang Jian-Ping Zhou Kai Li School of Mechanical Engineering Xinjiang UniversityUrumqi 830017China School of Mechano-Electronic Engineering Xidian UniversityXi’an 710017China Xi’an Institute of Optics and Precision Mechanics Chinese Academy of SciencesXi’an 710119China

Active reflectors are often used to compensate the surface distortion caused by environmental factors that degrade the electromagnetic performance of large high-frequency reflector *** is crucial for maintaining high gain operation in antennas.A distortion compensation method for the active reflector of a large dual-reflector antenna is proposed.A relationship is established between the surface deformation and the optical path difference for the primary reflector by geometric ***,employing finite element analysis,a polynomial fitting approach is used to describe the impact of adjusting points on the reflector surface based on the coordinates of each *** standardizing the positions of various panels on the reflector,the fitting ns can be applied to the reflector panels of similar ***,based on the distribution characteristics of the primary reflector panels,the adjustment equation for the actuators is derived by the influence matrix *** can be used to determine the adjustment amount of actuators to reduce the rms of the optical path ***,the least squares method is employed to resolve the matrix *** example of a 110 m aperture dual-reflector antenna is carried out by finite element analysis and the proposed *** results show that the optical path difference is reduced significantly at various elevation cases,which indicates that the proposed method is effective.

关键词： Methods analytical-Methods numerical-Telescopes

Recent progress of two-dimensional metal-base catalysts in urea oxidation reaction

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Rare Metals 2024年第8期43卷 3607-3633页

作者： Qi-xiang Huang Fang Wang Yong Liu Bi-Ying Zhang Fang-Ya Guo Zhong-Qiu Jia Hao Wang tian-xiang Yang Hai-Tao Wu Feng-Zhang Ren Ting-Feng Yi School of Materials Science and Engineering Henan University of Science and TechnologyLuoyang 471000China School of Environmental Engineering and Chemistry Luoyang Institute of Science and TechnologyLuoyang 471023China Henan Province International Joint Laboratory of Materials for Solar Energy Conversion and Lithium Sodium Based Battery Luoyang 471023China School of Chemistry and Life Sciences Suzhou University of Science and TechnologySuzhou 215009China School of Materials Science and Engineering Northeastern UniversityShenyang110819China

Urea oxidation reaction(UOR)is an auxiliary water electrolysis hydrogen production technology developed in recent years to replace oxygen evolution reaction and reduce energy consumption,which can produce hydrogen more efficiently by low theoretical potential,reduce the average cost of electrochemical hydrogen production,and is a frontier research hotspot for renewable hydrogen ***-dimensional(2D)nanomaterials as electrocatalysts have many favorable potential,such as it can effectively reduce the resistivity of materials and increase the specific surface area with *** paper reviews the application of 2D materials in UOR in alkaline *** a cross-sectional comparison of various material performance data including overpotential,Tafel slope,electrochemical active surface area(ECSA)and it stability test was conducted,which could illustrate the differences between materials composed of different *** addition,the main challenges hindering the progress of research on 2D materials in urea electrocatalysis processes and promising materials in this field in future are summarized and *** is believed that this review will contribute to designing and analyzing highperformance 2D urea electrocatalysts for water splitting.

关键词： Water splitting Urea oxidation reaction Two-dimensional Transition metal compounds Noble/non-noble metals

汉语和新诗彼此形塑的机制与启示——基于诗学、语言学交互视野的考察

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湖北大学学报（哲学社会科学版） 2024年第4期51卷 105-113,F0003页

作者：向天渊西南大学中国诗学研究中心中国新诗研究所重庆400715

基于诗学、语言学的交互视野,回顾汉语和新诗的现代化历程,可以发现,在“国语”及“文学”围绕文学性及生命意识展开双向互动、共同革新的大背景下,汉语和新诗相互牵缠、彼此形塑,既相得益彰,也彼此耗损。缘于表达现代生活方式、构建现... 详细信息

基于诗学、语言学的交互视野,回顾汉语和新诗的现代化历程,可以发现,在“国语”及“文学”围绕文学性及生命意识展开双向互动、共同革新的大背景下,汉语和新诗相互牵缠、彼此形塑,既相得益彰,也彼此耗损。缘于表达现代生活方式、构建现代价值体系的要求,现代汉语被迫走上欧化道路,只不过囿于汉字、汉语的物理属性及其所负载的精神传统,无法充分实现欧化目标,语言上的内在张力必然传导至诗歌层面,引发新诗语言民族性、现代性品格建构的悖论与困惑。时至今日,用现代汉语写作新诗,早已成为不争之事实,但新诗反哺现代汉语,予其诗性锻造,促其成为意蕴丰厚的诗性语言,仍然道阻且长。我们必须充分发掘现代汉语的诗性潜质,尽可能地拓展、增强新诗的语言智慧,创造出满足现代人的精神需求、适应现代社会发展的诗歌作品,走上诗歌与语言彼此促进、良性循环的现代汉语诗学之路。

关键词：汉语新诗新诗语言双向互动诗性语言汉语诗学

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使用实模态计算非比例阻尼系统的复模态

计算力学学报 2024年第4期41卷 790-794,800页

作者：魏向天吴柏生钟慧湘广东工业大学机电工程学院广州510006

提出一种利用实模态计算非比例阻尼系统复模态的新方法.首先,引入一个嵌入参数将无阻尼系统与阻尼系统联系起来,然后构造模态规范化条件.将非比例系统特征值和特征向量在无阻尼系统基础上对该参数实施摄动展开,得到展开系数的控制方程.... 详细信息

提出一种利用实模态计算非比例阻尼系统复模态的新方法.首先,引入一个嵌入参数将无阻尼系统与阻尼系统联系起来,然后构造模态规范化条件.将非比例系统特征值和特征向量在无阻尼系统基础上对该参数实施摄动展开,得到展开系数的控制方程.每个特征向量展开系数可借助Nelson法求解具有同一个对称实系数矩阵的方程组来求得.该方法仅涉及感兴趣的模态,无模态截断问题,不要求广义逆,也不需要将矩阵扩维.本文以两个数值算例来说明本文方法的有效性.

关键词：非比例阻尼复模态摄动展开模态规范化 Nelson方法

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编码孔径快照光谱成像重构算法综述

计算机学报 2024年第1期47卷 190-212页

作者：马祥天王立志黄华北京理工大学计算机学院北京100081 北京师范大学人工智能学院北京100875

光谱图像含有丰富的空间和光谱信息,能够反映目标的组成、结构和材料特性,在航天遥感、医疗诊断和机器视觉等领域具有重要的应用价值.近年来,光谱成像技术作为热点研究领域受到广泛关注.传统光谱成像技术采用沿空间维度或光谱维度扫描... 详细信息

光谱图像含有丰富的空间和光谱信息,能够反映目标的组成、结构和材料特性,在航天遥感、医疗诊断和机器视觉等领域具有重要的应用价值.近年来,光谱成像技术作为热点研究领域受到广泛关注.传统光谱成像技术采用沿空间维度或光谱维度扫描的方式,依次获取待测物体表面的光谱信息.由于曝光时间较长,传统光谱成像技术不适用于拍摄动态场景.编码孔径快照光谱成像(Coded Aperture Snapshot Spectral Imaging,CASSI)是光谱成像的前沿技术方案,能够从单次曝光中快速获取动态场景的光谱图像,其包括两个阶段:对高维光谱图像的“编码降维采集”和对低维观测图像的“解码升维重构”.CASSI的早期研究聚焦于“编码降维采集”,通过物理系统设计提升图像编码的有效性,包括编码模板设计和双相机系统设计.目前,CASSI的“编码降维采集”物理系统趋于稳定,其“解码升维重构”决定了光谱成像的质量和效率.本文综述CASSI的重构算法.首先介绍CASSI的物理系统和前向模型,详细描述物理系统的组成元件和硬件参数,推导CASSI前向模型的数学表达;其次梳理CASSI重构的特点和挑战,其挑战主要存在于系统前向模型、先验表示模型、算法灵活性、算法复杂度、实物数据集等方面;之后重点归纳重构算法的研究现状,包括基于优化模型的重构算法和基于深度学习的重构算法.基于优化模型的重构算法利用凸优化模型求解线性逆问题,结合平滑、稀疏、低秩等手工设计的先验表示模型降低逆问题的欠定性;基于深度学习的重构算法利用数据驱动的方式建立先验表示模型,结合端到端全网络、深度展开、即插即用等框架求解重构图像.接着比较主流算法的重构质量和计算效率,以峰值信噪比、结构相似度、光谱角制图为重构质量的评价指标,以模型参数量、浮点计算量为计算效率的评价指标.最后讨论现有工作的不足和未来研究趋势,指出当前仍未解决的领域痛点,展望进一步的研究方向,为本领域开拓创新提供参考.

关键词：快照光谱成像编码孔径图像重构优化模型深度学习