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Science China Earth Sciences 2004年第Z1期47卷 71-77页

作者： XIAO honglang CHENG Guodong li Xinrong SONG Yaoxuan WANG Xinping Shapotou Desert Experimental Research Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Shapotou Desert Experimental Research Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Shapotou Desert Experimental Research Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Shapotou Desert Experimental Research Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Shapotou Desert Experimental Research Station Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

Study is made on a 45 km-long artificial ecosystem without irrigation in Tengger desert on the basis of long-term ecological monitoring and ecohydrological *** in water allocation, utilization, cycle and balance patterns in more than 40-year evolution of the soil-plant system are analyzed. The formation of a drought horizon in shrub rhizosphere and its effect, ecohydrological function of the crust and its effect on the soil-plant system change are discussed. Driven by water self-regulation and water stress, the soil-plant system is going to develop towards the steppe desert to ensure more effective use and optimum collocation of water resource.

关键词： ecohydrology, artificial ecosystem, soil-plant evolution, water balance, drought horizon, bio-crust, Chinese desert.

Record-Breaking Frequency of 44 GHz Based on the Higher Order Mode of Surface Acoustic Waves with liNbO_(3)/SiO_(2)/SiC Heterostructures

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Engineering 2023年第1期20卷 112-119页

作者： Jian Zhou Dinghong Zhang Yanghui liu Fengling Zhuo lirong Qian honglang li Yong-Qing Fu Huigao Duan College of Mechanical and Vehicle Engineering Hunan UniversityChangsha 410082China Tianjin Key Laboratory of Film Electronic and Communication Devices School of Integrated Circuit Science and EngineeringTianjin University of TechnologyTianjin 30084China CAS Center for Excellence in Nanoscience National Center for Nanoscience and TechnologyBeijing 100190China Faculty of Engineering and Environment Northumbria UniversityNewcastle upon Tyne NE18STUK

Surface acoustic wave (SAW) technology has been extensively explored for wireless communication, sensors, microfluidics, photonics, and quantum information processing. However, due to fabrication issues, the frequencies of SAW devices are typically limited to within a few gigahertz, which severely restricts their applications in 5G communication, precision sensing, photonics, and quantum control. To solve this critical problem, we propose a hybrid strategy that integrates a nanomanufacturing process (i.e., nanolithography) with a liNbO_(3)/SiO_(2)/SiC heterostructure and successfully achieve a record-breaking frequency of about 44 GHz for SAW devices, in addition to large electromechanical coupling coefficients of up to 15.7%. We perform a theoretical analysis and identify the guided higher order wave modes generated on these slow-on-fast SAW platforms. To demonstrate the superior sensing performance of the proposed ultra-high-frequency SAW platforms, we perform micro-mass sensing and obtain an extremely high sensitivity of approximately 33151.9 MHz·mm2·μg−1, which is about 1011 times higher than that of a conventional quartz crystal microbalance (QCM) and about 4000 times higher than that of a conventional SAW device with a frequency of 978 MHz.

关键词： Ultra-high frequency SAW Higher order mode Hyper sensitive detection

A nonlinear analysis of surface acoustic waves in isotropic elastic solids

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Theoretical & Applied Mechanics Letters 2022年第2期12卷 98-103页

作者： Haoxiang Wu Rongxing Wu Tingfeng Ma Zixiao Lu honglang li Ji Wang Piezoelectric Device Laboratory School of Mechanical Engineering&MechanicsNingbo UniversityNingbo 315211China National Center for Nanoscience and Technology Beijing 100190China

With the fast evolution of wireless and networking communication technology,applications of surface acoustic wave(SAW),or Rayleigh wave,resonators are proliferating with fast shrinking sizes and increasing *** is inevitable that the smaller resonators will be under a strong electric field with induced large deformation,which has to be described in wave propagation equations with the consideration of *** this study,the formal nonlinear equations of motion are constructed by introducing the nonlinear constitutive relation and strain components in a standard procedure,and the equations are simplified by the extended Galerkin method through the elimination of *** wave velocity of the nonlinear SAW is obtained from approximated nonlinear equations and boundary conditions through a rigorous solution *** is shown that if the amplitude is small enough,the nonlinear results are consistent with the linear results,demonstrating an alternative procedure for nonlinear analysis of SAW devices working in nonlinear state.

关键词： Surface Wave Nonlinear Galerkin Resonator

Integrated sensor based on acoustics-electricity-mechanics coupling effect for wireless passive gas detection

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Nano Research 2023年第2期16卷 3130-3141页

作者： licheng Zhou Bohui Zhai Zhixiang Hu Mingqi Zhang Long li Xiangxin Wang Guangzu Zhang Jingting Luo honglang li Bingbing Chen Shenglin Jiang Hua-Yao li Huan liu School of Optical and Electronic Information Wuhan National Laboratory for OptoelectronicsOptics Valley LaboratoryHuazhong University of Science and TechnologyWuhan 430074China Shenzhen Huazhong University of Science and Technology Research Institute Shenzhen Virtual University ParkShenzhen 518000China Key Laboratory of Optoelectronic Devices and Systems College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060China CAS Center for Excellence in Nanoscience National Center for Nanoscience and TechnologyBeijing 100190China School of Energy Science and Engineering Nanjing Tech UniversityNanjing 211816China

Integrated sensor combines multiple sensor functions into a single unit,which has the advantages of miniaturization and better application ***,limited by the sensing platforms of the sensor and the selectivity of the sensitive film,there are still challenges to realize multi-component gas detection in one ***,a principle integration method is proposed to achieve the multi-component gas detection based on the acoustics-electricity-mechanics coupling *** electrical and mechanical properties of the Bi_(2)S_(3)nanobelts materials in different atmospheres indicate the possibility of realizing the principle *** the same time,the surface acoustic wave(SAW)sensor as a multivariable physical transducer can sense both electrical and mechanical *** exposure to 10 ppm NO_(2),NH_(3),and their mixtures,the integrated SAW gas sensor shows a 4.5 kHz positive frequency shift(acoustoelectric effect),an 11 kHz negative frequency shift(mechanics effects),and a reduced 4 kHz negative frequency shift(acoustics-electricity-mechanics coupling effect),***,we realize wireless passive detection of NO_(2)and NH_(3)based on the SAW *** work provides valuable insights that can serve as a guide to the design and fabrication of single sensors offering multi-component gas detection via different gas sensing mechanisms.

关键词： integrated gas sensor bismuth sulfide surface acoustic wave coupling effect wireless passive

Multiscale and hierarchical wrinkle enhanced graphene/Ecoflex sensors integrated with human-machine interfaces and cloud-platform

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npj Flexible Electronics 2022年第1期6卷 558-568页

作者： Jian Zhou Xinxin Long Jian Huang Caixuan Jiang Fengling Zhuo Chen Guo honglang li YongQing Fu Huigao Duan College of Mechanical and Vehicle Engineering Hunan UniversityChangsha 410082China National Center for Nanoscience and Technology Beijing 100190China Faculty of Engineering and Environment Northumbria UniversityNewcastle upon Tyne NE18STUnited Kingdom Greater Bay Area Institute for Innovation Hunan UniversityGuangzhou 511300 Guangdong ProvinceChina

Current state-of-the-art stretchable/flexible sensors have received stringent demands on sensitivity,flexibility,linearity,and widerange measurement ***,we report a methodology of strain sensors based on graphene/Ecoflex composites by modulating multiscale/hierarchical wrinkles on flexible *** sensor shows an ultra-high sensitivity with a gauge factor of 1078.1,a stretchability of 650%,a response time of~140 ms,and a superior cycling *** can detect wide-range physiological signals including vigorous body motions,pulse monitoring and speech recognition,and be used for monitoring of human respirations in real-time using a cloud platform,showing a great potential for the healthcare internet of *** gestures/sign languages can be precisely ***-machine interface is demonstrated by using a sensor-integrated glove to remotely control an external manipulator to remotely defuse a *** study provides strategies for real-time/long-range medical diagnosis and remote assistance to perform dangerous tasks in industry and military fields.

关键词： hierarchical durability cycling

Analysis of the acoustoelectric response of SAW gas sensors using a COM model

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Microsystems & Nanoengineering 2024年第3期10卷 87-96页

作者： Yang Yuan Tao Yang Xi Chen linglang Yu Xiaoxiao Hou Guangzu Zhang Wen Dong Zixiao Lu honglang li Leonhard Reindl Wei Luo School of Integrated Circuits Huazhong University of Science and Technology430074 WuhanPeople’s Republic of China CAS Center for Excellence in Nanoscience National Center for Nanoscience and Technology100190 BeijingPeople’s Republic of China Department of Microsystems Engineering Laboratory for Electrical Instrumentation and Embedded SystemsUniversity of Freiburg79110 FreiburgGermany Research Institute of Huazhong University of Science and Technology in Shenzhen 518057 ShenzhenPeople’s Republic of China

Surface acoustic wave(SAW)gas sensors based on the acoustoelectric effect exhibit wide application prospects for in situ gas ***,establishing accurate models for calculating the scattering parameters of SAW gas sensors remains a ***,we present a coupling of modes(COM)model that includes the acoustoelectric effect and specifically explains the nonmonotonic variation in the center frequency with respect to the sensing film’s sheet *** sensing parameters of the gas sensors,including the center frequency,insertion loss,and phase,were experimentally compared for accuracy and ***,the frequency of the phase extremum(FPE)shift was determined to vary monotonically,and the range of selectable test points was wide,making the FPE an appropriate response parameter for leveraging in SAW gas *** simulation results of the COM model were highly consistent with the experimental *** study is proposed to provide theoretical guidance for the future development of gas SAW sensors.

关键词： COM SAW establishing

Finite difference time domain analysis of two-dimensional surface acoustic wave piezoelectric phononic crystals at radio frequency

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Chinese Journal of Acoustics 2015年第3期34卷 257-266页

作者： TIAN Yahui li honglang KE Yabing LUO Wei WEI Jiangbo HE Shitang Institute of Acoustics Chinese Academy of Sciences School of Optical and Electrical Information Huazhong Univ.of Science & Technology Information-Electric Institute MESNAC co.ltd.

The finite-difference time-domain （FDTD） method is proposed for analyzing the surface acoustic wave （SAW） propagation in two-dimensional （2D） piezoelectric phononic crystals （PCs） at radio frequency （RF）, and also experiments are established to demonstrate its analysis result of the PCs＇ band gaps. The FDTD method takes the piezoelectric effect of PCs into account, in which periodic boundary conditions are used to decrease memory/time consumption and the perfectly matched layer boundary conditions are adopted as the SAW absorbers to attenuate artificial reflections. Two SAW delay lines are established with/without piezoelectric PCs located between interdigital transducers. By removing several echoes with window gating function in time domain, delay lines transmission function is achieved. The PCs＇ transmission functions and band gaps are obtained by comparing them in these two delay lines. When Aluminum/128°YX-liNbO3 is adopted as scatter and substrate material, the PCs＇ band gap is calculated by this FDTD method and COMSOL respectively. Results show that computational results of FDTD agree well with experimental results and are better than that of COMSOL.

关键词： FDTD Finite difference time domain analysis of two-dimensional surface acoustic wave piezoelectric phononic crystals at radio frequency COMSOL time wave

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直接附着式声表面波气体传感器的灵敏度分析

压电与声光 2010年第4期32卷 524-527页

作者：刘久玲李红浪何世堂中国科学院声学研究所北京100190

分析了直接附着式声表面波气体传感器的灵敏度。运用分层介质理论,对压电基底表面附着液膜后液膜参数变化所引起的频率变化进行分析,给出了相应的计算结果;然后计算了在500 MHz工作频率、考虑液膜轻度粘滞性时,声表面波气体传感器的检... 详细信息

分析了直接附着式声表面波气体传感器的灵敏度。运用分层介质理论,对压电基底表面附着液膜后液膜参数变化所引起的频率变化进行分析,给出了相应的计算结果;然后计算了在500 MHz工作频率、考虑液膜轻度粘滞性时,声表面波气体传感器的检测下限,结果为10-9量级;最后将计算结果与实验结果进行比较并得到验证。

关键词：气体传感器声表面波气相色谱灵敏度

不同入路的脾门区淋巴结清扫在腹腔镜胃癌根治术中的应用进展

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中华外科杂志 2015年第5期53卷 392-395页

作者：胡林李昌荣李红浪南昌大学第二附属医院胃肠外科 330006

腹腔镜下保留脾的脾门淋巴结清扫（LSPL）是尚处于实验性开展阶段的手术,目前报道有通过右侧、左侧、内侧、胰后等不同入路完成这一过程,本文归纳了不同入路LSPL的步骤及各自的特点,并比较彼此之间的差异.同时介绍了腹腔镜脾门淋巴结清... 详细信息

腹腔镜下保留脾的脾门淋巴结清扫（LSPL）是尚处于实验性开展阶段的手术,目前报道有通过右侧、左侧、内侧、胰后等不同入路完成这一过程,本文归纳了不同入路LSPL的步骤及各自的特点,并比较彼此之间的差异.同时介绍了腹腔镜脾门淋巴结清扫在胃癌根治术中的应用现状,并对其可行性、安全性、待解决的问题及改进措施进行了探讨.

关键词：胃肿瘤腹腔镜检查胃切除术淋巴结切除术

体质指数对腹腔镜胃癌根治术短期结局影响的Meta分析

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中华胃肠外科杂志 2015年第8期18卷 826-831页

作者：胡林李昌荣李伟峰李红浪南昌大学第二附属医院胃肠外科 330006

目的：评价体质指数（BMI）在腹腔镜胃癌根治术中对患者术后短期结局的影响。方法计算机检索PubMed、EMBASE、万方数据库、CNKI和中国生物医学文献数据库（CBM），2014年10月前发表的有关高BMI与低BMI胃癌患者行腹腔镜胃癌根治术的文献... 详细信息

目的：评价体质指数（BMI）在腹腔镜胃癌根治术中对患者术后短期结局的影响。方法计算机检索PubMed、EMBASE、万方数据库、CNKI和中国生物医学文献数据库（CBM），2014年10月前发表的有关高BMI与低BMI胃癌患者行腹腔镜胃癌根治术的文献，采用RevMan 5．2软件对所纳入的数据进行荟萃分析，应用Stata 12．0统计软件进行Begg及Egger检验以评估纳入文献的发表偏倚。结果12项回顾性队列研究共计4798例患者纳入分析，其中高BMI组1215例，低BMI组3583例。 Meta分析结果显示：与低BMI组相比，高BMI组患者手术时间延长（SMD＝0．64，95％CI：0．35-0．93，P＝0．000），失血量较多（SMD＝0．63，95％CI：0．24-1．03，P＝0．002），清扫淋巴结数量较少（SMD＝－0．44，95％CI：－0．72-－0．17，P＝0．002）、术后总并发症发生率较高（OR＝1．44，95％CI：1．19-1．74， P＝0．000）；两组间住院时间、术后恢复排气时间及分项比较并发症发生情况的差异无统计学意义（均P＞0．05）。结论高BMI会导致腹腔镜胃癌根治术手术时间延长，术中出血量增加，术后并发症发生风险增大。

关键词：体质指数腹腔镜胃肿瘤胃切除术 Meta分析