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Non-contact optical dynamic measurements at different ranges:a review

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Acta Mechanica Sinica 2021年第4期37卷 537-553,I0001页

作者： Yu Fu Yang Shang Wenxin Hu Bin Li Qifeng Yu Shenzhen key laboratory of Intelligent Optical Measurement and detection Shenzhen UniversityShenzhen 518060China Hunan Provincial key laboratory of Image Measurement and Vision Navigation College of Aerospace Science and EngineeringNational University of Defense TechnologyChangsha 410073China

Optical dynamic measurements are widely used for non-contact vibration,continuous deformation,or moving *** measurement techniques were developed for different deformation *** paper reviews three types of technique for different measurement ranges:interferometric techniques for deformation or vibration(nanometer to submillimeter amplitude)whose measurement accuracies rely on phase extraction of interferometric signal;imaging based techniques for deformation or vibration(micrometer to centimeter amplitude)with the aid of moire,structured light,and man-made speckles,whose sensitivities is from 1/100 to 1/10 pixel;and videometrics for large deformation or movement detection(greater than centimeter amplitude).Many research groups have improved measurement capabilities for these three techniques to meet particular industrial application requirements.

关键词： Vibration measurement Laser interferometry Digital image correlation High-speed imaging Videometrics

Single-mode GaSb-based laterally coupled distributed-feedback laser for CO_(2)gas detection

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Chinese Physics B 2023年第10期32卷 443-447页

作者：韩实现严进一曹春芳杨锦杜安天陈元宇刘若涛王海龙龚谦 key laboratory of Terahertz Solid State technology Shanghai Institute of Microsystem and Information TechnologyShanghai 200050China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Shandong Provincial key laboratory of Laser polarization and Information technology School of Physics and Physical EngineeringQufu Normal UniversityQufu 273165China

We report on a GaSb-based laterally coupled distributed feedback(LC-DFB)laser with Cr gratings operating at 2004 nm for CO_(2)detection *** packaged with single-mode fiber pigtailed,the laser diode operates in the continuous-wave mode in a temperature range from-10℃to 60℃,with a maximum output power of 2 mW and a maximum side-mode suppression ratio over 30 ***-modulated absorption spectroscopy of CO_(2)demonstrates the applicability of the LC-DFB laser to tunable diode laser absorption ***,the diode junction temperature,which is measured by using the wavelength shift method,exhibits a maximum value of 17℃in the single-mode operation range.

关键词： semiconductor lasers quantum wells laser spectroscopy

Theory and method of dual-energy x-ray grating phase-contrast imaging

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Chinese Physics B 2019年第10期28卷 597-602页

作者： Feng Rong Yan Gao Cui-Juan Guo Wei Xu Wei Xu College of Electronics and Information Engineering Tianjin Polytechnic UniversityTianjin 300387China Tianjin key laboratory of Optoelectronic detection technology and System Tianjin Polytechnic UniversityTianjin 300387China

The principle of dual-energy x-ray grating phase-contrast imaging(DEPCI) is clarified by using the theory of x-ray interference and Fresnel diffraction. A new method of retrieving phase from the two interferograms is proposed for DEPCI,and its feasibility is verified via simulation. Finally, the proposed method applied to DEPCI experiment demonstrates the effectiveness of the method. This paper lays the theoretical foundation for performance optimization of DEPCI and the further integration of DEPCI and computed tomography.

关键词： x-ray imaging dual-energy analyzer grating phase retrieval

Recent Advances in Surface-Assisted Laser Desorption/Ionization Mass Spectrometry and Its imaging for Small Molecules

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Journal of Analysis and Testing 2022年第3期6卷 217-234页

作者： Huan Huang Dan Ouyang Zi-An Lin Ministry of Education key laboratory of Analytical Science for Food Safety and Biology Fujian Provincial Key Laboratory of Analysis and Detection Technology for Food SafetyCollege of ChemistryFuzhou UniversityFuzhou 350108China

Mass spectrometry imaging(MSI)has provided a new perspective on acquiring spatial information of multiple molecules in various *** the different ionization methods,matrix-assisted laser desorption/ionization(MALDI)has been widely utilized for detecting macromolecules,with difficulty for small molecules(m/zimaging(SALDI-MSI).In the last 5 years,different kinds of nanomaterials have been widely explored as substrates including metal/metal oxide-based,carbon-based,silicon-based,metal-organic frameworks-based,covalent organic frameworksbased substrates,with growing interests on composite materials and nanomaterials with homogeneous film *** review highlights recent advances of various nanomaterials as SALDI substrates,and their emerging imaging applications in botanic,forensic,metabolic and pathological ***,the merits and limitations of SALDI-MS are sketched out and some recommendations of this technique and its imaging are proposed.

关键词： Nanomaterials Surface-assisted laser desorption ionization(SALDI) Mass spectrometry imaging(MSI) Small molecules

Elastic-Wave Reverse Time Migration Random Boundary-Noise Suppression Based on CycleGAN

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Journal of Ocean University of China 2022年第4期21卷 849-860页

作者： XU Guohao HE Bingshou key laboratory of the Ministry of Education for Seafloor Science and detection technology Ocean University of ChinaQingdao 266100China Functional laboratory of Marine Mineral Resources Evaluation and Exploration technology Qingdao National Laboratoryof Marine Science and TechnologyQingdao 266100China

In elastic-wave reverse-time migration(ERTM),the reverse-time reconstruction of source wavefield takes advantage of the computing power of GPU,avoids its disadvantages in disk-access efficiency and reading and writing of temporary files,and realizes the synchronous extrapolation of source and receiver *** the existing source wavefield reverse-time reconstruction algorithms,the random boundary algorithm has been widely used in three-dimensional(3D)ERTM because it requires the least storage of temporary files and low-frequency disk access during reverse-time ***,the existing random boundary algorithm cannot completely destroy the coherence of the artificial boundary reflected *** random boundary reflected wavefield with a strong coherence would be enhanced in the cross-correlation image processing of reverse-time migration,resulting in noise and fictitious image in the migration results,which will reduce the signal-to-noise ratio and resolution of the migration section near the *** overcome the above issues,we present an ERTM random boundary-noise suppression method based on generative adversarial ***,we use the Resnet network to construct the generator of CycleGAN,and the discriminator is constructed by using the PatchGAN ***,we use the gradient descent methods to train the *** fix some parameters,update the other parameters,and iterate,alternate,and continuously optimize the generator and discriminator to achieve the Nash equilibrium state and obtain the best network ***,we apply this network to the process of reverse-time *** snapshot of noisy wavefield is regarded as a 2D matrix data picture,which is used for training,testing,noise suppression,and *** method can identify the reflected signal in the wavefield,suppress the noise generated by the random boundary,and achieve *** examples show that the proposed method can significantly improve the i

关键词： random boundary reverse-time migration generative adversarial network noise suppression

Sequence-activated chemiluminescence probes: programmable illumination for high-contrast in vivo sensing and imaging

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Science China Chemistry 2025年第1期 26-34页

作者： Yutao Zhang Juan Li Wei-Hong Zhu Zhiqian Guo Shanghai key laboratory of Functional Materials Chemistry Joint International Research Laboratory of Precision Chemistry and Molecular Engineering Institute of Fine Chemicals School of Chemistry and Molecular Engineering East China University of Science and Technology State key laboratory of Bioreactor Engineering Shanghai Frontier Science Research Base of Optogenetic Techniques for Cell MetabolismEast China University of Science & Technology

Sequence-activated chemiluminescence(CL) technique offers a unique approach to detecting specific biomolecules or cellular events with high sensitivity and spatial resolution. The fundamental principle behind sequence-activated CL probes involves tailoring highly-controllable CL signals in response to specific sequences or events of interest, thus enabling high-contrast signals under complex physiological conditions. This sequential activation could be triggered by enzymes, reactive oxygen species(ROS), biothiols or changes in the microenvironment. These unique sequence-activated CL probes bestow several advantages, including minimal background, deep-tissue penetration, and the ability of non-invasive or minimally invasive detection. The sequence-activated CL techniques represent a significant advancement in molecular imaging and diagnostics. In this mini-review, we focus on the latest developments in sequential CL probes, addressing the technical challenges and discussing the future trajectory by harnessing CL signaling and molecular recognition.

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Transverse Zeeman background correction method for air mercury measurement

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Chinese Physics B 2014年第10期23卷 458-463页

作者：李传新司福祺刘文清周海金江宇胡仁志 Department of Optics and Optical Engineering University of Science and Technology of China key laboratory of Environmental Optics and technology. anhui Institute of Optics and Fine Mechanics Chinese Academy of Sciences

By utilizing a natural mercury lamp, the transverse Zeeman background correction method, which is used for trace mercury measurement in air, is studied. In this paper, a natural mercury lamp is used as a light source, and is placed in a 1.78-T magnetic field. The lamp emits two linearly polarized light beams σ± and π of 253.65-nm resonance line, which are used as bias light and absorbing light, respectively. A polarization modulation system is used to allow σ± and π light beams to pass through alternately with a certain frequency. A multipath optical cell with 12-m optical path is used to increase optical distance. Based on the system described above, the influence caused by UV absorbing gases, such as NO2, SO2, acetone, benzene, and O3, is analyzed. The results show that it may reduce the detection limit when the concentrations of these gases exceed 83.4 ppm, 20.3 ppm, 142.3 ppm, 0.85 ppm, and 0.55 ppm, respectively. The detection limit of the system is calculated and can achieve up to 1.44 ng/m3 in 10 minutes. Measurements on mercury sample gas and air are carded out, and the measured data are compared with the data of RA-915 mercury analyzer （Russia）. The result shows that the correlation coefficient reaches up to 0.967. The experimental results indicate that the transverse Zeeman background correction method can be used to quantify trace mercury in air with high-precision.

关键词： transverse Zeeman background correction natural mercury lamp magnetic field multipath opticalcell

Effect of transient space-charge perturbation on carrier transport in high-resistance CdZnTe semiconductor

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Chinese Physics B 2019年第11期28卷 304-307页

作者： Yu Guo Gang-Qiang Zha Ying-Rui Li Ting-Ting Tan Hao Zhu Sen Wu MIIT key laboratory of Radiation detection Materials and Devices State Key Laboratory of Solidification ProcessingSchool of Materials Science and EngineeringNorthwestern Polytechnical University(NWPU)Xi’an 710072China

The polarization effect introduced by electric field deformation is the most important bottleneck of CdZnTe detector in x-ray imaging. Currently, most of studies focus on electric field deformation caused by trapped carriers;the perturbation of electric field due to drifting carriers has been rarely reported. In this study, the effect of transient space-charge perturbation on carrier transport in a CdZnTe semiconductor is evaluated by using the laser-beam-induced current(LBIC) *** appear in the current curves of CdZnTe detectors with different carrier transport performances under intense excitation, indicating the deformation of electric field. The current signals under different excitations are compared. The results suggest that with the increase of excitation, the amplitude of cusp increases and the electron transient time gradually decreases. The distortion in electric field is independent of carrier transport performance of detector. Transient space-charge perturbation is responsible for the pulse shape and affects the carrier transport process.

关键词： CdZnTe transient space-charge perturbation laser-beam-induced current(LBIC) technique carrier transport

Dynamically Tunable Perfect Absorbers Utilizing Hexagonal Aluminum Nano-Disk Array Cooperated with Vanadium Dioxide

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Chinese Physics Letters 2019年第1期36卷 19-23页

作者： Peng Zhou Gai-Ge Zheng Yun-Yun Chen Feng-Lin Xian Lin-Hua xu Jiangsu key laboratory for Optoelectronic detection of Atmosphere and Ocean School of Physics and Optoelectronic Engineering Nanjing University of Information Science & Technology Jiangsu Collaborative Innovation Center on Atmospheric Environment and Equipment technology Nanjing University of Information Science & Technology

A tunable perfect absorber composed of hexagonal-arranged aluminum nano-disk array embedded in the vanadium dioxide(VO_2) film is proposed. The aim is to achieve the tunability of resonance absorption peak in the visible and near-infrared regimes. Numerical results reveal that the absorption peak achieves a large tunability of 76.6% while VO_2 undergoes a structural transition from insulator phase to metallic phase. By optimizing the structural parameters, an average absorption of 95% is achieved from 1242 to 1815 nm at the metallic phase state. In addition, the near unity absorption can be fulfilled in a wide range of incident angle(0°–60°) and under all polarization conditions. The method and results presented here would be beneficial for the design of active optoelectronic devices.

关键词： Vanadium Dioxide Hexagonal aluminum nanodisc array absorbent