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基于改进的多分量频率-贝塞尔变换法研究郯庐断裂带潍坊段上地壳径向各向异性结构

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地球物理学报 2024年第3期67卷 1037-1052页

作者：周桂理罗松姚华建中国科学技术大学地球和空间科学学院合肥230026 中国科学技术大学蒙城地球物理国家野外科学观测研究站安徽蒙城230026

郯庐断裂带潍坊段位于郯庐断裂带中部,具有复杂的地质结构,总体呈现“两堑夹一垒”的构造格局.相比于郯庐断裂带其他区域,潍坊段地震活动性较弱,属于地震空区,未来发生大地震的可能性尚不明确.前人对该地区的研究目前仅局限于速度结构... 详细信息

郯庐断裂带潍坊段位于郯庐断裂带中部,具有复杂的地质结构,总体呈现“两堑夹一垒”的构造格局.相比于郯庐断裂带其他区域,潍坊段地震活动性较弱,属于地震空区,未来发生大地震的可能性尚不明确.前人对该地区的研究目前仅局限于速度结构和方位各向异性结构,对于上地壳径向各向异性结构特征鲜有报道.因此,研究该区域上地壳速度模型和径向各向异性结构,有助于更好地认识郯庐断裂带潍坊段浅地壳(V_(SV)),这可能与早期地壳伸展沉积导致的水平变形结构有关.2~5 km,四个区域径向各向异性结构各有不同,但总体处于由负到正的转折状态.这可能因为2~5 km不仅受到断裂结构的控制作用,也受到水平沉积结构的影响,导致径向各向异性结构较为复杂.

关键词：改进的多分量频率-贝塞尔变换法径向各向异性郯庐断裂带沂沭断裂带背景噪声

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高帧率超声造影在肝局灶性病变中的诊断价值

中国医学影像学杂志 2024年第5期32卷 473-478页

作者：张雪菡周青周乔丹陈琴遵义医科大学贵州遵义563000 四川省医学科学院·四川省人民医院超声科四川成都610072

目的探讨高帧率超声造影(H-CEUS)在肝脏局灶性病变(FLLs)定性诊断中的应用价值。资料与方法回顾性收集2021年8月—2022年8月四川省人民医院的72例FLLs。所有患者均先行常规超声发现病灶,后行超声造影(CEUS)及H-CEUS,对比两种方法显示的... 详细信息

目的探讨高帧率超声造影(H-CEUS)在肝脏局灶性病变(FLLs)定性诊断中的应用价值。资料与方法回顾性收集2021年8月—2022年8月四川省人民医院的72例FLLs。所有患者均先行常规超声发现病灶,后行超声造影(CEUS)及H-CEUS,对比两种方法显示的开始增强时间、增强方向、血管形态、峰值强度、增强均匀度等,评估CEUS、H-CEUS对FLLs的诊断价值。结果相较于CEUS,H-CEUS能够更清楚地显示FLLs动脉期增强方向、血管形态及增强后均匀度。CEUS、H-CEUS诊断FLLs的敏感度、特异度、准确度、阳性预测值、阴性预测值、曲线下面积分别为87.10%、96.77%,85.37%、87.80%,86.11%、91.67%,81.82%、85.71%,89.74%、97.30%,0.862、0.923。结论相较于CEUS,H-CEUS能够更清楚地显示病灶动脉期特征性表现,为FLLs的诊断提供了更丰富、可靠的信息,对FLLs具有较高的诊断效能。

关键词：肝疾病肝肿瘤超声检查造影剂

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基于滚动接触的单模块多自由度柔性连续体机械臂设计

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工程设计学报 2024年第4期31卷 473-482页

作者：周亮温涛胡俊峰周浩江西理工大学机电工程学院江西赣州341000

为实现连续体机械臂的多模态运动,解决现有机械臂只能实现单一弯曲或旋转的问题,设计了一种基于滚动接触的单模块多自由度柔性连续体机械臂。将滚动接触模块作为连续体机械臂弯曲模块的骨架结构,并在弯曲模块内安装旋转模块,以形成具备... 详细信息

为实现连续体机械臂的多模态运动,解决现有机械臂只能实现单一弯曲或旋转的问题,设计了一种基于滚动接触的单模块多自由度柔性连续体机械臂。将滚动接触模块作为连续体机械臂弯曲模块的骨架结构,并在弯曲模块内安装旋转模块,以形成具备独立弯曲和旋转运动的多自由度机械臂。采用分段常曲率法建立连续体机械臂的运动学模型,对其刚度性能、弯曲性能和旋转性能进行了分析。制备了连续体机械臂样机,并开展机械臂拧松瓶盖、开启风扇以及在三维空间内避开障碍物抓取目标物体等实验。实验结果表明,利用连续体机械臂的弯曲与旋转组合运动可完成复杂空间环境下的不同任务,体现了复合运动模式的优势。所设计的连续体机械臂具备多模态运动,可为多自由度连续体机械臂的设计提供新思路,拓展了连续体机械臂的应用场景。

关键词：柔性连续体机械臂单模块滚动接触多模态运动

A NIR to NIR rechargeable long persistent luminescence phosphor Ca_(2)Ga_(2)GeO_(7):Yb^(3+),Tb^(3+)

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Journal of Rare Earths 2021年第12期39卷 1520-1526,I0003页

作者： Junhe zhou Zhangwen long Jianbei Qiu Dacheng zhou Jun'an Lai Xuhui Xu Songhan Hu Xizheng Li Qi Wang Faculty of Material Science and Engineering Kunming University of Science and TechnologyKunming 650093China Institute of Advanced Materials(IAM) Jiangsu National Synergetic Innovation Center for Advanced Materials(SICAM)Nanjing Tech UniversityNanjing 211816China Key Lab.of Advanced Materials of Yunnan Province Kunming 650093China

Near infrared to near infrared(NIR-NIR)photo-stimulated persistent luminescence(PSPL)has shown excellent potential in high-resolution bioimaging for deep ***,the PSPL in NIR-Ⅱregion(900-1700 nm)is still *** this work,Ca_(2)Ga_(2)GeO_(7):Yb^(3+),Tb^(3+)(CGGYT)phosphor with unique lowdimensional crystal structure was synthesized by high-temperature solid-state *** to the carriers transferring from deep traps to shallow ones induced by low energy light,the 978 nm PSPL originating from ^(2)F_(5/2) to ^(2)F_(7/2) transition of Yb^(3+)induced by multimode stimulating(980 nm or WLED)is successfully realized after pre-excited by UV *** NIR PSPL of the specimen can be repeatedly stimulated after placed in dark for 12 ***,the results indicate that codoping with Tb^(3+)can significantly enhance the NIR-ⅡPSPL owing to the quantum cutting persistent energy transfer(QC PET)from Tb^(3+)to Yb^(3+).Our study points to a new direction for the future development of multimode PSPL materials for bioimaging or multimode optical storage applications.

关键词： Rechargeable long persistent luminescence Near infrared emission Yb^(3+) Trap Energy transfer Rare earths

基于评价编码的高校智慧图书馆空间布局优化设计策略研究

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鞋类工艺与设计 2024年第7期4卷 183-185页

作者：叶棉谢珩龙舟邱海东海南大学国际传播与艺术学院海南海口570208

本文立足用户体验,通过半结构化问卷调查法获取当前高校智慧图书馆建设与发展中存在的问题,并将其进行数据编码带入用户体验五层模型之中得到结果。通过研究高校图书馆用户体验的影响因素,提出未来的高校智慧图书馆的空间布局优化提供... 详细信息

本文立足用户体验,通过半结构化问卷调查法获取当前高校智慧图书馆建设与发展中存在的问题,并将其进行数据编码带入用户体验五层模型之中得到结果。通过研究高校图书馆用户体验的影响因素,提出未来的高校智慧图书馆的空间布局优化提供新的思路,以期构建合乎用户行为的智慧图书馆多功能复合型空间布局体系。

关键词：用户体验多功能复合型空间高校智慧图书馆评价编码法

Full-scale experiment for segmental linings of deep-buried shield tunnels bearing high inner water pressure:Comparison of mechanical behaviors of continuous-and stagger-jointed structures

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Underground Space 2023年第1期8卷 252-266页

作者： long zhou Yi Shen Linxing Guan Zhiguo Yan Wei Sun Yaoliang Li College of Civil Engineering Tongji UniversityShanghai 200092China State Key Laboratory of Disaster Reduction in Civil Engineering Tongji UniversityShanghai 200092China Shanghai Municipal Engineering Design Institute(Group)Co.Ltd. Shanghai 200092China Shanghai Foundation Engineering Group Co.Ltd. Shanghai 200002China

Full-scale loading tests were performed on shield segmental linings bearing a high earth pressure and high inner water pressure,focus-ing on the effects of the inner water load and assembly manner on the mechanical properties of the segmental *** test results indicate that the deep-buried segmental linings without inner pressure have a high safety *** the action of high inner water pressure,the lining deformation will increase with the reduction of the safety reserve,caused by the significant decrease in the axial force in the *** the bending moment at the segmental joints is transferred to the segment sections in the adjacent ling rings,the convergence deformation,openings of segmental joints,and bolt strains are smaller for the stagger-jointed lining than those for the continuous-jointed lining;however,dislocations appear in the circumferential joints owing to the stagger-jointed *** it significantly improves the mechanical performance of the segmental lining,stagger-jointed assembly results in compromising the water-proofing safety of circumferential *** stagger-jointed assembly manner can be considered to improve the service performance of shield tunnels bearing high inner water pressure on the premise that circumferential joint waterproofing is satisfied.

关键词： Shield tunnel Inner water pressure Continuous-jointed lining Stagger-jointed lining Full-scale experiment

Optimizing luminescence sensitivity and moisture stability of porous coordination frameworks by varying ligand side groups

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Science China Chemistry 2019年第3期62卷 341-346页

作者： Jia-Wen Ye Xu-Yu Li Hao-long zhou Jie-Peng Zhang MOE Key Laboratory of Bioinorganic and Synthetic Chemistry School of Chemistry Sun Yat-Sen University

Hydrophobic ethyl, butyl or hexyl groups were introduced into the dicarboxylate ligand in the fluorescent porous coordination framework [Zn_2(fda)_2(bpy)](LMOF-202, H_2fda=9H-fluorene-2,7-dicarboxylic acid, bpy=4,4′-bipyridine) for improving water stability and tuning oxygen sensitivity. The long hexyl groups gave satisfactory water stability but its oxygen sensitivity is low(70.8% fluorescence quenched at 1 bar O_2(1 bar=105 Pa)). In contrast, the shorter side groups gave high oxygen sensitivity(93.9% fluorescence quenched at 1 bar O_2) and low water stability. The derivation of the Stern-Volmer curves of the O_2 luminescence quenching data from the linear form can be used for detecting trace impurities in the luminescent framework, being much more sensitive than conventional methods such as powder X-ray diffraction. Mixing the ethyl and hexyl groups in the solid-solution manner brought high oxygen sensitivity(96.4% fluorescence quenched at 1 bar O_2) and high water stability simultaneously in the same coordination framework.

关键词： metal-organic framework water stability oxygen fluorescence sensor

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煤矿智能化建设中存在的问题及其对策研究

中国煤炭 2024年第2期50卷 30-34页

作者：周洪军周宗林国家矿山安全监察局安徽局安徽省合肥市230092

在对全国4省(区)20个单位煤矿智能化建设调研的基础上,全面深入地分析了当前煤矿智能化建设工作中存在的发展不平衡等突出问题。认为,这些问题既有政策、法规及标准规范层面,也有智能技术及智能装备层面,还有管理层面,需要予以高度重视... 详细信息

在对全国4省(区)20个单位煤矿智能化建设调研的基础上,全面深入地分析了当前煤矿智能化建设工作中存在的发展不平衡等突出问题。认为,这些问题既有政策、法规及标准规范层面,也有智能技术及智能装备层面,还有管理层面,需要予以高度重视。同时,提出加强政府引导和政策支持、加强智能化关键技术攻关、及时修订标准规范、加强政策引领提升煤炭科技创新驱动能力、做好煤矿智能化建设顶层设计、加强数据综合分析平台建设和加大相关人才培养力度等对策建议。

关键词：煤矿智能化建设标准规范技术装备突出问题对策建议

Numerical evaluation of segmental tunnel lining with voids in outside backfill

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Underground Space 2022年第5期7卷 786-797页

作者： Jia-Xuan Zhang Ning Zhang Annan zhou Shui-long Shen Department of Civil Engineering School of Naval ArchitectureOceanand Civil EngineeringShanghai Jiao Tong UniversityShanghai 200240China MOE Key Laboratory of Intelligent Manufacturing Technology Department of Civil and Environmental EngineeringCollege of EngineeringShantou UniversityShantouGuangdong 515063China Discipline of Civil and Infrastructure School of EngineeringRoyal Melbourne Institute of Technology(RMIT)Victoria 3001Australia

This paper presents a numerical investigation of the mechanical behaviour of segmental linings owing to the existence of voids in the composite *** composite lining was formed by mining outside and shield tunnelling inside with backfill in *** element method was conducted to analyse the axial forces and bending moment for voids of different diameters at different *** results show that the axial forces in the transverse section increase near the crown and then invert and decrease on the left and right sides with an increase in the void centre angle(β)measured from the vertical *** increase in void diameter(d<300 mm)induces an increase in the axial force on the left and right sides when β=45°and 90°,while it decreases near the crown and *** occurrence of voids leads to an increase in the bending moment in the entire segment section with an angle β.

关键词： Jointly constructed tunnel Composite lining Voids Axial force Bending moment