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热风干燥细胞尺度水分传输及收缩数值模拟

工程热物理学报 2024年第2期45卷 543-550页

作者：范芃佐王鹏李政赢董冰北京石油化工学院机械工程学院北京102617

目前植物物料热风干燥过程中品质变化机理未得到充分地研究,原因之一是对细胞尺度上干燥特性认识不足。本文基于模型细胞,针对细胞中不同的结构建立水分传输模型,并建立力学模型模拟细胞失水过程中的收缩现象,实现热风干燥过程植物细胞... 详细信息

目前植物物料热风干燥过程中品质变化机理未得到充分地研究,原因之一是对细胞尺度上干燥特性认识不足。本文基于模型细胞,针对细胞中不同的结构建立水分传输模型,并建立力学模型模拟细胞失水过程中的收缩现象,实现热风干燥过程植物细胞尺度上的水分传输和收缩变形的模拟。通过与文献结果对比验证了本文模拟结果的正确性,分析了植物细胞中不同结构在水分传输和失水收缩过程的规律,以及细胞收缩变形对其水分传输的影响,为从细胞尺度分析物料的干燥特性打下基础。

关键词：热风干燥植物细胞水分传输失水收缩数值模拟

Coherent-detection-based distributed acoustic impedance sensing enabled by a chirped fiber Bragg grating array

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Photonics Research 2022年第6期10卷 1325-1331页

作者： ZHOU ZHENG zhengying li XUELEI FU XIN GUI Hubei Key Laboratory of Broadband Wireless Communication and Sensor Networks School of Information EngineeringWuhan University of TechnologyWuhan 430070China National Engineering Laboratory for Fiber Optic Sensing Technology Wuhan University of TechnologyWuhan 430070China State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China

Distributed optical fiber sensing exploring forward stimulated Brillouin scattering(FSBS)has received wide attention,as it indicates a new sensing method to measure the liquid property surrounding an optical *** the existing techniques,backward stimulated Brillouin scattering is adopted for detection of the sensing signal,which requires time-consuming signal acquisition and *** this work,an approach that distributedly measures FSBS spectra is proposed and demonstrated based on coherent *** an excitation pulse with single-frequency amplitude modulation is used to induce a guided acoustic mode in the fiber,a following pulse is adopted to probe the induced phase *** a chirped fiber Bragg grating array,an enhancedbackward-propagating sensing signal is generated from the probe *** coherent-detection-based phase demodulation is then realized by mixing the sensing signal with a local *** FSBS spectra can then be reconstructed from the beat signals with only one round of frequency *** significantly accelerated signal acquisition and simplified post-processing,the proposed distributed acoustic sensing system has achieved spatial resolution of 5 m over a 500-m sensing range.

关键词： fiber scattering backward

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儿童腹股沟巨大疝的诊治进展

现代医药卫生 2024年第1期40卷 143-146页

作者：李正英(综述) 张晓杰(审校) 长春中医药大学吉林长春130117

腹股沟斜疝是儿童外科最常见的外科疾病,其主要原因是鞘状突闭合失败,而在腹压增大时出现临床症状,当患儿年龄超过1岁后内环口(IR)闭合概率降低,所以此时应进行治疗,且主要采取手术治疗。随着腹腔镜技术的发展,儿童腹股沟斜疝的微创治... 详细信息

腹股沟斜疝是儿童外科最常见的外科疾病,其主要原因是鞘状突闭合失败,而在腹压增大时出现临床症状,当患儿年龄超过1岁后内环口(IR)闭合概率降低,所以此时应进行治疗,且主要采取手术治疗。随着腹腔镜技术的发展,儿童腹股沟斜疝的微创治疗得到了广泛的开展。在腹腔镜下腹股沟斜疝可根据IR的直径分为巨大型(IR直径大于或等于1.5 cm)、普通型(IR直径0.5~<1.5 cm)、隐匿型(IR直径小于0.5 cm)。针对不同类型的腹股沟斜疝其术式也更加细化,而对于儿童巨大的腹股沟斜疝治疗也有多种术式。该文回顾性分析国内外相关文献,就儿童巨大腹股沟斜疝的诊治进展进行综述。

关键词：腹腔镜微创巨大疝儿童手术治疗

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少先队活动用书中国家认同教育内容研究

基础教育研究 2024年第9期 9-12页

作者：王立虹樊广明李政莹甘肃庆阳市庆化学校庆阳745000

少先队活动用书内容丰富,主题多样。立足于国家认同教育已有的理论,结合对教材的内容分析,发现少先队活动用书中的国家认同教育内容具有占比高、线索明、规律强、用意远、重榜样等特点。据此特点,坚持以儿童为本,提高活动参与的积极性;... 详细信息

少先队活动用书内容丰富,主题多样。立足于国家认同教育已有的理论,结合对教材的内容分析,发现少先队活动用书中的国家认同教育内容具有占比高、线索明、规律强、用意远、重榜样等特点。据此特点,坚持以儿童为本,提高活动参与的积极性;加强师资培训,增强组织活动的胜任力;重视活动载体,彰显“一级一特色”的科学性;紧扣主题活动,发掘校内外优质资源;合理使用教材,开发完善课程资源体系,探索利用少先队组织阵地开展国家认同教育的实践路径。

关键词：少先队活动国家认同内容分析

Laser spectroscopy imaging technique coupled withnanomaterials for cancer diagnosis: A review

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Journal of Innovative Optical Health Sciences 2024年第1期17卷 1-27页

作者： zhengying Peng Pengkun Yin Dan li Youyuan Chen Kaiqiang Shu Qingwen Fan Yixiang Duan Qingyu lin Key Laboratory of Bio-Resource and Eco-Environment Ministry of Education College of Life Sciences Sichuan University Chengdu 610064 SichuanP.R.China Research Center of Analytical Instrumentation School of Mechanical Engineering Sichuan University Chengdu 610064SichuanP.R.China Key Laboratory of Green Chemistry&Technology of Ministry of Education College of Chemistry Sichuan University Chengdu 610064 SichuanP.R.China State Key Laboratory of Membrane Biology Beijing Advanced Innovation Center for Structural Biology School of life Sciences Tsinghua University Beijing 100084P.R.China

Laser spectroscopic imaging techniques have received tremendous attention in the-eld of cancer diagnosis due to their high sensitivity,high temporal resolution,and short acquisition ***,the limited tissue penetration of the laser is still a challenge for the in vivo diagnosis of deep-seated *** have been universally integrated with spectroscopic imaging techniques for deeper cancer diagnosis in *** components,morphology,and sizes of nanomaterials are delicately designed,which could realize cancer diagnosis in vivo or in *** the enhanced signal emitting from the nanomaterials,we emphasized their combination with spectroscopic imaging techniques for cancer diagnosis,like the surface-enhanced Raman scattering(SERS),photoacoustic,fluorescence,and laser-induced breakdown spectroscopy(liBS).Applications ofthe above spectroscopic techniques offer new prospectsfor cancer diagnosis.

关键词： Laser spectroscopy tumor imaging tumor diagnosis nanomaterials

Research on Multi-Component Gas Optical Detection System Based on Conjugated Interferometer

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Photonic Sensors 2017年第3期7卷 261-269页

作者： Xin GUI Yuheng TONG Honghai WANG Haihu YU zhengying li National Engineering Laboratory for Fiber Optic Sensing Technology Wuhan University of Technology Wuhan 430070 China Key Laboratory of Fiber Optic Sensing Technology and Information Processing Ministry of Education Wuhan University of Technology Wuhan 430070 China

An optical multi-component gas detection system based on the conjugated interferometer （CI） is proposed and experimentally demonstrated. It can realize the concentration detection of mixture gas in the environment. The CI can transform the absorption spectrum of the target gases to a conjugated emission spectrum, when combining the CI with the broadband light source, the spectrum of output light matches well with the absorption spectrum of target gases. The CI design for different target gases can be achieved by replacing the kind of target absorbing gas in the CI filter. The traditional fiber gas sensor system requires multiple light sources for detection when there are several kinds of gases, and this problem has been solved by using the CI filter combined with the broadband light source. The experimental results show that the system can detect the concentration of multi-component gases, which are mixed with C2H2 and NH3. Experimental results also show a good concentration sensing linearity.

关键词： Gas conjugated interference filter gas sensing spectral absorption

High-Speed Mach-Zehnder-OTDR Distributed Optical Fiber Vibration Sensor Using Medium-Coherence Laser

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Photonic Sensors 2018年第3期8卷 203-212页

作者： Yuheng TONG zhengying li Jiaqi WANG Honghai WANG Haihu YU National Engineering Laboratory for Fiber Optic Sensing Technology Wuhan University of Technology Wuhan 430070 China

This article presents a high-speed distributed vibration sensing based on Mach-Zehnder-OTDR （optical time-domain reflectometry）. Ultra-weak fiber Bragg gratings （UWFBG）, whose backward light intensity is 2-4 orders of magnitude higher than that of Rayleigh scattering, are used as the reflection markers. A medium-coherence laser can substitute conventional narrow bandwidth source to achieve an excellent performance of distributed vibration sensing since our unbalanced interferometer matches the interval of UWFBGs. The 3 m of spatial resolution of coherent detection and multiple simultaneous vibration sources locating can be realized based on OTDR. The enhanced signal to noise ratio （SNR） enables fast detection of distributed vibration without averaging. The fastest vibration of 25 kHz and the slowest vibration of 10Hz can be detected with our system successfully, and the linearity is 0.9896 with a maximum deviation of 3.46nε.

关键词： High-speed Mach-Zehnder-OTDR ultra-weak fiber Bragg grating array medium-coherence laser optical fiber vibration sensing

Control mode selection for modal control of long-span arch bridge

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Frontiers of Structural and Civil Engineering 2009年第4期3卷 401-406页

作者： zhengying li Zhengliang li Faculty of Civil Engineering Chongqing UniversityChongqing 400030China

For seismic control of arch bridge,a model reduction of long-span arch bridge was implemented based on modal *** for the critical mode selection,an approach based on the maximum modal displacement was *** approach takes into consideration the effect of external seismic excitation and is more reasonable than only considering dynamic bridge characteristics based on a modal contribution *** time domain and frequency domain analysis method were used to verify the simplified model of the Nimu arch bridge in Tibet as an *** numerical results show that the method of maximal modal displacement better analyze long-span arch bridge when multisupport seismic excitation must be *** reduced-order system also is more in line with the performance of the original model.

关键词： arch bridges vibration control model reduction modal analysis maximum modal displacement

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基于多颜色空间的烟叶颜色表征方法研究

南方农机 2024年第4期55卷 5-10,25页

作者：张志成吴箭杨泽会李正莹张晓兵王昕李瑞东吕小芳彭云发徐梦瑶云南烟叶复烤有限责任公司宣威复烤厂云南曲靖655400 浙江中烟工业有限责任公司技术中心浙江杭州310024 浙江中烟工业有限责任公司物资部浙江杭州310002 云南烟叶复烤有限责任公司技术中心云南昆明650000 上海创和亿电子科技发展有限公司上海200084

【目的】实现云南产地烟叶颜色表征,输出真正意义上能够反映云南宣威复烤厂初烤烟叶颜色特征的信息。【方法】课题组利用工业相机采集烟叶图像,对烟叶图像进行预处理、彩色图像分割,将烟叶图像分别转换到RGB、HSV、Lab等多颜色空间,采... 详细信息

【目的】实现云南产地烟叶颜色表征,输出真正意义上能够反映云南宣威复烤厂初烤烟叶颜色特征的信息。【方法】课题组利用工业相机采集烟叶图像,对烟叶图像进行预处理、彩色图像分割,将烟叶图像分别转换到RGB、HSV、Lab等多颜色空间,采用投影寻踪法,将多颜色空间下的各颜色分量信息进行融合,使用综合值对烟叶颜色进行表征,并分析了使用多颜色空间的表征方法是否优于单颜色空间。【结果】1)融合多颜色空间计算出的颜色表征值与专家排序结果的相关系数高达0.98;2)单独使用RGB、HSV、Lab颜色空间进行颜色表征的相关系数分别为0.95、0.62、0.76,这表明多颜色空间包含了更多颜色信息,其表征值更能反映烟叶颜色特征。【结论】该方法可快速把烟叶真实的颜色信息提取出来,并且与人工排序的符合度较高,可实现在线应用,并为烟叶外观颜色均质化加工提供控制指标和数据支撑。

关键词：烟叶均质化颜色空间投影寻踪