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Zonal disintegration phenomenon in enclosing rock mass surrounding deep tunnels——Elasto-plastic analysis of stress field of enclosing rock mass

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Mining Science and Technology 2009年第3期19卷 84-90页

作者： WU Hao FANG Qin ZHANG Ya-dong GONG zi-ming Engineering Institute of Engineering Corps PLA University of Science and Technology Nanjing Jiangsu 210007 China

The zonal disintegration phenomenon （ZDP） is a typical phenomenon in deep block rock masses. In order to investigate the mechanism of ZDP, an improved non-linear Hock-Brown strength criterion and a bi-linear constitutive model of rock mass were used to analyze the elasto-plastic stress field of the enclosing rock mass around a deep round tunnel. The radius of the plastic region and stress of the enclosing rock mass were obtained by introducing dimensionless parameters of radial distance. The results show that tunneling in deep rock mass causes a maximum stress zone to appear in the vicinity of the boundary of the elastic and the plastic zone in the surrounding rock mass. Under the compression of a large tangential force and a small radial force, the rock mass in the maximum stress zone was in an approximate uniaxial loading state, which could lead to a split failure in the rock mass.

关键词： enclosing rock mass around deep tunnels zonal disintegration equivalent material Hoek-Brown strength criterion

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A modified-Liutex-based vortex-core-line extractor and its application

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Journal of Hydrodynamics 2023年第4期35卷 811-824页

作者： Jin-yan Cai Dong Li zi-ming Xu Ze-yu Zhang Jiao-lin Cui School of Aeronautics Northwestern Polytechnical UniversityXi’an710072China High Speed Aerodynamics Institute China Aerodynamics Research and Development CenterMianyang621000China

Vortices,which appear as swirling behaviour of a flow field,are an important phenomenon in fluid dynamics,and the extraction of vortex cores is necessary for the research of vortex evolution in many areas of fluid *** Liutex method is a milestone in vortex identification and provides a reasonable mathematical definition for a vortex *** on this definition,a novel integration-based method is presented,which can reduce the numerical error in the integration process through location *** typical test cases,the wake vortices of an A320 in the near-ground stage and a helicopter rotor,are examined to show that the proposed method can extract continuous vortex core lines with accuracy and efficiency for vortex parameter study.

关键词： Vortex definition flow visualization Liutex vortex core lines optimization

New anthraquinone derivatives from the roots of Berchemia floribunda

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Chinese Chemical Letters 2007年第4期18卷 412-414页

作者： Xin Wei Jian Shuang Jiang zi ming Feng Pei Cheng Zhang Key Laboratory of Bioactive Substances and Resources Utilization of Chinese Herbal Medicine （Ministry of Education） Institute of Materia Medica Chinese Academy of Medical Sciences and Peking Union Medical College Beifing 100050 China

A new naphthoquinone-anthraquinone dimer named floribundiquinone E （1） and a new anthraquinone 2-acetylphyscion （2） were isolated from the roots of Berchemia floribunda Brongn. Their structures were elucidated on ... 详细信息

关键词： Berchemia floribunda Anthraquinone Floribundiquinone E 2-Acetylphyscion

临床中医肝胆病学领域大模型构建思路与方法研究

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中西医结合肝病杂志 2024年第9期34卷 769-774页

作者：李君李紫明毛树松李晓东湖北中医药大学中医临床学院湖北武汉430061 湖北中医药大学信息工程学院湖北省中医院肝病研究所、中医肝肾研究及应用湖北省重点实验室湖北中医药大学附属医院湖北省中医药研究院

人类社会已经进入智能化新时代,人工智能的核心技术从“AI判别式小模型”向“AI产生式大模型”飞速演进,创建大语言模型已经成为高新科学技术发展的前沿。在此背景下,面对临床中医学领域智能化,制定临床中医学领域大模型研究策略与方法... 详细信息

人类社会已经进入智能化新时代,人工智能的核心技术从“AI判别式小模型”向“AI产生式大模型”飞速演进,创建大语言模型已经成为高新科学技术发展的前沿。在此背景下,面对临床中医学领域智能化,制定临床中医学领域大模型研究策略与方法,已经成为中医临床智能化亟待解决的重大科学问题。本文以中医肝胆病学领域为例,提出基于知识仓库与开源大语言模型的深度融合创新性的临床中医肝胆病学领域大模型构建思路与方法,并探讨了应用临床中医肝胆病学领域大模型开展基于大数据知识工程的真实世界中医临床研究;培育中医临床研究新质生产力,形成具有先进理念的新业态,应用高新技术、赋能守正创新、实现中医临床的高质量发展等方面的重要学术价值和广阔应用前景。

关键词：人工智能中医临床大模型知识仓库中医肝胆病学

Ferroelectric Ba_(0.75)Sr_(0.25)TiO_(3) tunable charge transfer in perovskite devices

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Chinese Physics B 2022年第5期31卷 602-608页

作者： zi-Xuan Chen Jia-Lin Sun Qiang Zhang Chong-Xin Qian ming-zi Wang Hong-Jian Feng School of Physics Northwest UniversityXi’an 710127China

Interfacial charge recombination is a main issue causing the efficiency loss of the perovskite solar cells(PSCs).Here,ferroelectric Ba_(0.75)Sr_(0.25)TiO_(3)(BST)is introduced as a polarization tunable layer to promote the interfacial charge transfer of the *** coexistence of ferroelectric polarization and charge carriers in BST is confirmed by density functional theory(DFT)*** characterization demonstrates the polarization reversal and the existence of domain in BST *** BST film conductivity is tested as 2.98×10^(-4)S/cm,which is comparable to the TiO;being used as the electron transporting layer(ETL)in *** calculations results prove that BST can be introduced into the PSCs and the interfacial charge transfer can be tuned by ferroelectric ***,we fabricated the BST-based PSCs with a champion power conversion efficiency(PCE)of 19.05%after poling.

关键词： ferroelectric polarization charge transfer density-functional theory perovskite solar cell

Gastrointestinal symptoms as the first sign of chronic granulomatous disease in a neonate: A case report

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World Journal of Clinical Cases 2021年第32期9卷 9997-10005页

作者： Er-Yan Meng zi-ming Wang Bing Lei Li-Hong Shang Division of Neonatology The Third Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina Chongqing Medical College Chongqing 400016China

BACKGROUND Chronic granulomatous disease(CGD)characterized by recurrent and severe bacterial and fungal infections is most common in *** SUMMARY We reported a 24-d-old male infant who developed gastrointestinal symptoms as the first sign of *** Gastrointestinal symptoms representing the first sign of CGD are very rare,and prompt diagnosis and treatment with broad-spectrum antibiotics were of crucial importance.

关键词： Chronic granulomatous disease Gastrointestinal symptoms Infant Neonate Fever Diarrhea

The ultratrace detection of crystal violet using surface enhanced Raman scattering on colloidal Ag nanoparticles prepared by electrolysis

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Chinese Chemical Letters 2009年第6期20卷 711-715页

作者： Ren ming Liu Yi Pu Kang Xing Fa zi ming Jun Feng Man Cheng Min Zhen Si Application Institute of Spectroscopy Technology Chuxiong Normal University Chuxiong 675000 China

Highly active, stable and affordable surface enhanced Raman scattering （SERS） substrates were obtained by electrolyzing a mixture of AgNO3 （4 × 10^-4 mol/L） and Na3C6H5OTH2O （6 × 10^-5 mol/L） for 1, 2, 3 and 4 h at 7 V. With crystal violet （CV） as a test molecule, a portable Raman spectrometer with 785 nm laser excitation was employed to carry out the SERS detection. Colloidal Ag nanoparticles prepared by electrolyzing for 3 h with the particle size of （65 ±17） nm is a perfect SERS substrate for the ultratrace detection of CV, which displayed an enhancement factor of ca. 1.3 × 10^8 and the detection limit of CV is down to ca. 10-15 mol/L （ca. 10^-4 ppb） with 10^-1 mol/L KBr as aggregating agent. Thus, this SERS substrate will provide a hopeful foreground in ultratrace detection. Meanwhile, it will provide a possibility to bring Raman analysis out of the laboratory to process in situ, real-time detection and identification.

关键词： SERS Ultratrace detection Crystal violet Silver nanoparticle Electrolysis

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宽温域VL型密封结构应力分析及寿命预测

化工机械 2024年第3期51卷 423-432页

作者：孙德清冯子明赵岩董振刚东北石油大学机械科学与工程学院温州大学机电工程学院大庆油田力神泵业有限公司

建立VL密封结构模型,在不同温度条件下,研究其应力状态分布。以Miner损伤机理为基础,疲劳累计损伤理论为指导,研究不同温度条件下,VL型密封结构中O型橡胶圈、L型圈的疲劳寿命变化规律和疲劳寿命状况。结果表明:随着温度增加,O型橡胶圈的... 详细信息

建立VL密封结构模型,在不同温度条件下,研究其应力状态分布。以Miner损伤机理为基础,疲劳累计损伤理论为指导,研究不同温度条件下,VL型密封结构中O型橡胶圈、L型圈的疲劳寿命变化规律和疲劳寿命状况。结果表明:随着温度增加,O型橡胶圈的Mises应力变化不大,疲劳寿命先增加后减小,当温度为25℃时,危险点处疲劳寿命最大,为7.341×10^(7)次,且疲劳寿命随着温度的增加,由局部变化转变为整体变化;L型圈的Mises应力由60.19 MPa逐渐减小到26.38 MPa,位置由底部开始,向内壁转移,最后到L型圈内部为止,最小疲劳寿命为2.21×10^(5)次。此外,在低温环境下,L型圈最小疲劳寿命较小,但平均疲劳寿命较大;在高温环境下,L型圈最小疲劳寿命较大,但平均疲劳寿命较小。

关键词： VL型密封结构宽温域疲劳累计损伤理论

面向数据科学与大数据技术专业的知识图谱构建

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电脑与电信 2024年第1期 32-34,71页

作者：王梓铭肖大薇刘亚楠大连理工大学城市学院辽宁大连116600

知识图谱已经在知识表示和管理方面进行了创新,广泛应用于智能搜索和问答等领域,但在教育教学领域的应用相对较少。基于知识图谱和自然语言处理技术,梳理课程教学计划的主要组成要素,从人才培养方案和课程教学计划中抽取课程实体、属性... 详细信息

知识图谱已经在知识表示和管理方面进行了创新,广泛应用于智能搜索和问答等领域,但在教育教学领域的应用相对较少。基于知识图谱和自然语言处理技术,梳理课程教学计划的主要组成要素,从人才培养方案和课程教学计划中抽取课程实体、属性和关系等信息,设计了数据科学与大数据技术专业课程体系本体模型,实现了数据科学与大数据技术专业课程体系知识图谱的构建。

关键词：数据科学与大数据技术知识图谱 Neo4j图数据库