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Microsystems & Nanoengineering 2024年第1期10卷 67-78页

作者： Yong Pan Cancan Yan Xu Gao Junchao Yang Tengxiao Guo Lin Zhang Wen Wang State Key Laboratory of NBC Protection for Civil Beijing 102205China Institute of Acoustics Chinese Academy of SciencesBeijing 100190China The School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijing 100049China

Long-term monitoring of environmental warfare agengts is a challenge for chemical gas sensors.To address this issue,we developed a 433 MHz Passive wireless surface acoustic wave(WSAW)gas sensor for dimethyl methylphosphonate(DMMP)detection.This WSAW gas sensor includes a YZ lithium niobate(LiNbO_(3))substrate with metallic interdigital transducers(IDTs)etched on it,and an antenna was placed near the IDT.A DMMP-sensitive viscoelastic polymer fluoroalcoholpolysiloxane(SXFA)film was prepared on a LiNbO_(3) substrate,and mode modeling coupling was used to optimize the design parameters.The sensor can function properly in an environments between−30℃ and 100℃ with humidity less than 60%RH.When the wireless transmission distance was within the range of 0-90 cm,the sensor noise increased with distance,and the stability was less than 32°/h.While optimizing the film thickness of SXFA,a relationship was observed between sensor sensitivity and film thickness.When the film thickness of SXFA reached 450 nm,the optimal value was reached.At a distance of 20 cm between the transmitting and receiving antennas,DMMP was detected at different concentrations with the developed WSAW gas sensor.The lower detection limit of DMMP was 0.48 mg/m^(3),the sensitivity of the sensor was 4.63°/(mg/m^(3)),and repeatable performance of the sensor was confirmed.

关键词： film alcohol Passive

An in vitro demonstration of a Passive,acoustic metamaterial as a temperature sensor with mK resolution for implantable applications

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Microsystems & Nanoengineering 2024年第1期10卷 41-54页

作者： Lucrezia Maini Vicente Genovés Roman Furrer Nikola Cesarovic Christofer Hierold Cosmin Roman Micro-and Nanosystems Department of Mechanical and Process EngineeringETH ZurichTannenstrasse 38092 ZurichSwitzerland. Translational Cardiovascular Technology Department of Health Science and TechnologyETH ZurichLeopold-Ruzicka-Weg 48093 ZurichSwitzerland. Transport at Nanoscale Interfaces Swiss Federal Laboratories for Materials Science and TechnologyEMPAÜberlandstrasse 1298600 DübendorfSwitzerland Department of Cardiothoracic and Vascular Surgery Deutsches Herzzentrum der Charite(DHZC)13353 BerlinGermany

Wireless medical sensors typically utilize electromagnetic coupling or ultrasound for energy transfer and sensor interrogation.Energy transfer and management is a complex aspect that often limits the applicability of implantable sensor systems.In this work,we report a new Passive temperature sensing scheme based on an acoustic metamaterial made of silicon embedded in a polydimethylsiloxane matrix.Compared to other approaches,this concept is implemented without additional electrical components in situ or the need for a customized receiving unit.A standard ultrasonic transducer is used for this demonstration to directly excite and collect the reflected signal.The metamaterial resonates at a frequency close to a typical medical value(5 MHz)and exhibits a high-quality factor.Combining the design features of the metamaterial with the high-temperature sensitivity of the polydimethylsiloxane matrix,we achieve a temperature resolution of 30 mK.This value is below the current standard resolution required in infrared thermometry for monitoring postoperative complications(0.1 K).We fabricated,simulated,in vitro tested,and compared three acoustic sensor designs in the 29-43℃(~302-316 K)temperature range.With this concept,we demonstrate how our Passive metamaterial sensor can open the way toward new zero-power smart medical implant concepts based on acoustic interrogation.

关键词： Passive resolution utilize

A Passive optical fibre sensor based on Fabry-Perot interferometry for bipolar electrostatic monitoring of insulating dielectrics

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High Voltage 2023年第4期8卷 682-689页

作者： Jiawei Zhang Zifan Ye Li Wang Zelei Zhang Fan Xu Weichen Dang Takao Matsumoto Sombel Diaham Chatchai Putson School of Electrical Engineering Xi'an University of TechnologyXi'anShaanxiChina Universitéde Toulouse UPSINPTLAPLACE(Laboratoire Plasma et Conversion d'Energie)Toulouse Cedex 9France Materials Physics Laboratory Department of PhysicsFaculty of SciencePrince of Songkla University(PSU)SongkhlaThailand

The measurement of the surface charge on the insulating dielectrics is critical to estimate the insulation strength of electrical equipment in operation.Unavoidable interactions with the electromagnetic field,however,generally result in distortion measurement of active sensor.Thus,it is of great significance to investigate a Passive sensor for monitoring the deposited charge.Here,a Passive optical fibre electrostatic sensor is developed on the principle of Fabry–Perot interference to quantify the surface potential of the insulating dielectrics.The sensitivity of quantifying the electrostatic charge is explored in terms of the wavelength shift in the interference spectrum,and the linear correlation is 0.99.Meanwhile,the sensor can identify a negative quadratic trend with the increase of the surface roughness of the insulating dielectrics.The merits of the proposed sensor such as Passive monitoring,bipolar electrostatic detection,and the excellent ability of antielectromagnetic interference are highlighted in the results.Hence,this sensor can serve as an effective tool to monitor the electrostatic charge in the fields of smart electrical equipment,fuel transportation,aerospace,integrate circuit etc.

关键词： electrostatic Passive fibre

Effect of boron on dissolution and repairing behavior of Passive film on S31254 super-austenitic stainless steel immersed in H_(2)SO_(4) solution

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Journal of Iron and Steel Research(International) 2022年第6期29卷 1012-1025页

作者： Tong-hao Wang Jian Wang Jin-gang Bai Shu-jing Wang Chao Chen Pei-de Han School of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024ShanxiChina Technology Center Shanxi Taigang Stainless Steel Co.Ltd.Taiyuan 030003ShanxiChina

The impact of boron on the dissolution and repairing behavior of Passive films formed on S31254 super-austenitic stainless steel(SASS)was investigated.SASS was immersed in 0.5 mol/L of H_(2)SO_(4) for 0,2,6,10,and 14 days to explore the evolution of the Passive film.The electrochemical impedance spectroscope(EIS),the Mott–Schottky analysis,and X-ray photoelectron spectroscope were utilized to analyze the semiconductor properties and compositions of the Passive films.EIS showed a decrease and consequent increase over 14 days;the same pattern was observed for Cr_(2)O_(3) and Cr/Fe.However,the defect density of the Passive film exhibited a reverse trend.The variation in film thicknesses indicated that the Passive films possessed dissolution and repairing behavior.SASS Passive film had a double-layer structure;the outer layer was found to be rich in Fe3+and Cr(OH)3,but low on Mo6+,while the inner layer was rich in Cr_(2)O_(3) and low in Mo4+.The addition of boron increased the corrosion resistance and could promote the efficiency of the Passive film repair,likely by promoting the migration of Mox+,which promoted the repairing of the Passive film.

关键词： Passive film S31254 super-austenitic stainless steel Boron Dissolution Repairing

High-sensitivity nanophotonic sensors with Passive trapping of analyte molecules in hot spots

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Light(Science & Applications) 2021年第1期10卷 60-70页

作者： Xianglong Miao Lingyue Yan Yun Wu Peter Q.Liu Department of Electrical Engineering University at BuffaloThe State University of New YorkBuffaloNY 14260USA Department of Biomedical Engineering University at BuffaloThe State University of New YorkBuffaloNY 14260

Nanophotonic resonators can confine light to deep-subwavelength volumes with highly enhanced near-field intensity and therefore are widely used for surface-enhanced infrared absorption spectroscopy in various molecular sensing applications.The enhanced signal is mainly contributed by molecules in photonic hot spots,which are regions of a nanophotonic structure with high-field intensity.Therefore,delivery of the majority of,if not all,analyte molecules to hot spots is crucial for fully utilizing the sensing capability of an optical sensor.However,for most optical sensors,simple and straightforward methods of introducing an aqueous analyte to the device,such as applying droplets or spin-coating,cannot achieve targeted delivery of analyte molecules to hot spots.Instead,analyte molecules are usually distributed across the entire device surface,so the majority of the molecules do not experience enhanced field intensity.Here,we present a nanophotonic sensor design with Passive molecule trapping functionality.When an analyte solution droplet is introduced to the sensor surface and gradually evaporates,the device structure can effectively trap most precipitated analyte molecules in its hot spots,significantly enhancing the sensor spectral response and sensitivity performance.Specifically,our sensors produce a reflection change of a few percentage points in response to trace amounts of the amino-acid proline or glucose precipitate with a picogram-level mass,which is significantly less than the mass of a molecular monolayer covering the same measurement area.The demonstrated strategy for designing optical sensor structures may also be applied to sensing nano-particles such as exosomes,viruses,and quantum dots.

关键词： trapping Passive spots

Monitoring gas-and particulate-phase short-chain polychlorinated paraffins in the urban air of Dalian by a self-developed Passive sampler

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Journal of Environmental Sciences 2019年第6期31卷 287-295页

作者： Yifan Wang Xiuhua Zhu Yuan Gao Hao Bai Pengyuan Wang Jiping Chen Heping Yuan Longxing Wang Xiaoxiao Li Wei Wang School of Environmental and Chemical Engineering Dalian Jiaotong University Dalian Institute of Chemical Physics Chinese Academy of Sciences College of Chemistry Jilin University Dalian Meteorological Observatory

The concentration of short-chain polychlorinated paraffins(SCCPs) in the urban air of Dalian,China was monitored from September 2016 to August 2017 with a self-developed Passive sampler(PAS1) and an active high-volume sampler, simultaneously. PAS1 successfully collected the entire target SCCPs in the ambient air. Air SCCPs sampled by PAS1 were found be in the linear uptake stage during 181 days of sampling. Passive and active samples showed comparable congener profiles, and the dominant contributors of SCCPs in the two kinds of samples were similar. A significant linear correlation was observed between the total concentration of SCCPs sampled by PAS1 and active sampler in the four seasons. The Passive sampling rates of the PAS1 for the gas and particulate phases of SCCPs were measured. The quantitative structure–property relationship of the sampling rate of PAS1(Rair) for gas-phase SCCPs was studied. From the molecular point of view, Rairwas mainly affected by the molecular weight and sub-cooled liquid vapor pressure of SCCPs. In general, SCCPs in the urban air of Dalian mainly existed in gas phase,lower molecular weight SCCPs primarily occurred in the gas phase, whereas higher molecular weight SCCPs were predominately adsorbed or absorbed on airborne particles. The air concentration of SCCPs in the four seasons were different, the correlation of the concentration of SCCPs in the air with the meteorology parameters was conducted. The exposure risk by intake air SCCPs of the residents around the sampling sites was evaluated according to the European risk assessment standards.

关键词： Ambient air Short-chain polychlorinated paraf fins Passive sampler Active sampling Passive sampling

Unlocking the monolithic integration scenario: optical coupling between GaSb diode lasers epitaxially grown on patterned Si substrates and Passive SiN waveguides

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Light(Science & Applications) 2023年第7期12卷 1381-1390页

作者： Andres Remis Laura Monge-Bartolome Michele Paparella Audrey Gilberto Guilhem Boissier Marco Grande Alan Blake Liam O'Faolain Laurent Cerutti Jean-Baptiste Rodriguez Eric Tournie ES University of MontpellierCNRSF-34000 MontpellierFrance Department of Electrical and Information Engineering Polytechnic University of Bari4 Via E OrabonaIT-70126 BariItaly Tyndall National Institute Lee Maltings ComplexDyke ParadeIR-T12R5CP CorkIreland Centre for Advanced Photonics and Process Analysis Munster Technological UniversityBishopstownIR-T12P928 CorkIreland

Silicon(Si)photonics has recently emerged as a key enabling technology in many application fields thanks to the mature Si process technology,the large silicon wafer size,and promising Si optical properties.The monolithic integration by direct epitaxy of III-V lasers and Si photonic devices on the same Si substrate has been considered for decades as the main obstacle to the realization of dense photonics chips.Despite considerable progress in the last decade,only discrete III-V lasers grown on bare Si wafers have been reported,whatever the wavelength and laser technology.Here we demonstrate the first semiconductor laser grown on a patterned Si photonics platform with light coupled into a waveguide.A mid-IR GaSb-based diode laser was directly grown on a pre-patterned Si photonics wafer equipped with SiN waveguides clad by SiO_(2).Growth and device fabrication challenges,arising from the template architecture,were overcome to demonstrate more than 10 mw outpower of emitted light in continuous wave operation at room temperature.In addition,around 10%of the light was coupled into the SiN waveguides,in good agreement with theoretical calculations for this butt-coupling configuration.This work lft an important building block and it paves the way for future low-cost,large-scale,fully integrated photonic chips.

关键词： diode Passive coupling

Metamaterial-enhanced near-field readout platform for Passive microsensor tags

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Microsystems & Nanoengineering 2022年第2期8卷 203-215页

作者： Ke Wu Guangwu Duan Xiaoguang Zhao Chunxu Chen Stephan William Anderson Xin Zhang Department of Mechanical Engineering Boston UniversityBostonMA 02215USA Photonics Center Boston UniversityBostonMA 02215USA Department of Radiology Boston University Medical CampusBostonMA 02118USA

Radiofrequency identification(RFID),particularly Passive RFID,is extensively employed in industrial applications to track and trace products,assets,and material flows.The ongoing trend toward increasingly miniaturized RFID sensor tags is likely to continue as technology advances,although miniaturization presents a challenge with regard to the communication coverage area.Recently,efforts in applying metamaterials in RFID technology to increase power transfer efficiency through their unique capacity for electromagnetic wave manipulation have been reported.In particular,metamaterials are being increasingly applied in far-field RFID system applications.Flere,we report the development of a magnetic metamaterial and local field enhancement package enabling a marked boost in near-field magnetic strength,ultimately yielding a dramatic increase in the power transfer efficiency between reader and tag antennas.The application of the proposed magnetic metamaterial and local field enhancement package to near-field RFID technology,by offering high power transfer efficiency and a larger communication coverage area,yields new opportunities in the rapidly emerging Internet of Things(loT)era.

关键词： Passive offering yielding

Adaptive Robust Control for a Lower Limbs Rehabilitation Robot Running Under Passive Training Mode

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IEEE/CAA Journal of Automatica Sinica 2019年第2期6卷 493-502页

作者： Xiaolong Chen Han Zhao Shengchao Zhen Hao Sun Hefei University of Technology

This paper focuses on the problem of the adaptive robust control of a lower limbs rehabilitation robot(LLRR) that is a nonlinear system running under Passive training mode. In reality, uncertainties including modeling error, initial condition deviation, friction force and other unknown external disturbances always exist in a LLRR system. So, it is necessary to consider the uncertainties in the unilateral man-machine dynamical model of the LLRR we described. In the dynamical model, uncertainties are(possibly fast) time-varying and bounded. However, the bounds are unknown. Based on the dynamical model, we design an adaptive robust control with an adaptive law that is leakagetype based and on the framework of Udwadia-Kalaba theory to compensate for the uncertainties and to realize tracking control of the LLRR. Furthermore, the effectiveness of designed control is shown with numerical simulations.

关键词： Adaptive robust control lower limbs rehabilitation robot mechanical system Passive training uncertainties

A modified logarithmic spiral method for determining Passive earth pressure

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Journal of Rock Mechanics and Geotechnical Engineering 2018年第6期10卷 1171-1182页

作者： Shiyi Liu Yang Xia Li Liang School of Resources and Civil Engineering Northeastern University State Key Laboratory of Structural Analysis for Industrial Equipment School of Automotive Engineering Dalian University of Technology

In this study, a modified logarithmic spiral method is proposed to determine the Passive earth pressure and failure surface of cohesionless sloping backfill, with presence of wallesoil interface friction. The proposed method is based on a limit equilibrium analysis wherein the assumed profile of the backfill failure surface is a composite of logarithmic spiral and its tangent. If the wallesoil interface is smooth, a straight line does not need to be assumed for the failure surface. The geometry of the failure surface is determined using the Mohr circle analysis of the soil. The resultant Passive earth thrust is computed considering equilibrium of moments. The Passive earth pressure coefficients are calculated with varied values of soil internal friction angle and cohesion, wall friction angle and inclination angle, and sloping backfill angle. This method is verified with the finite element method(FEM) by comparing the horizontal Passive earth pressure and failure surface. The results agree well with other solutions, particularly with those obtained by the FEM. The implementation of the present method is efficient. The logarithmic spiral theory is rigorous and self-explanatory for the geotechnical engineer.

关键词： Passive earth pressure Logarithmic spiral method Finite element method(FEM) Sloping backfill Retaining wall