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期刊论文 59

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关键词

6G;标准制定;太赫兹;算力网络;通信感知一体化 1

X射线 1

信道测量;信道建模;6G;太赫兹;工业互联网;空天地一体化网络;机器学习 1

傅立叶红外光谱 1

催化剂活化 1

分子荧光光谱 1

原位谱学 1

含能材料 1

多尺度测量 1

天然溶解有机质 1

太赫兹和光学诊断 1

太赫兹技术 1

太赫兹时域光谱;微腔;金属孔阵列;波导腔;伪局域表面等离子体 1

太赫兹通信;反射系数建模;入射角;建筑材料;菲涅耳模型 1

太赫兹;回溯天线阵列;太赫兹通信;共轭混频 1

定向耦合器;3-dB分支波导定向耦合器;亚毫米波器件;太赫兹电路;机械可靠性 1

干涉仪;光纤传感器;激光光谱学 1

微米器件 1

成像 1

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Time of flight improved thermally grown oxide thickness measurement with terahertz spectroscopy

《机械工程前沿(英文)》 2022年 第17卷 第4期 doi: 10.1007/s11465-022-0705-3

摘要: As a nondestructive testing technique, terahertz time-domain spectroscopy technology is commonly used to measure the thickness of ceramic coat in thermal barrier coatings (TBCs). However, the invisibility of ceramic/thermally grown oxide (TGO) reflective wave leads to the measurement failure of natural growth TGO whose thickness is below 10 μm in TBCs. To detect and monitor TGO in the emergence stage, a time of flight (TOF) improved TGO thickness measurement method is proposed. A simulative investigation on propagation characteristics of terahertz shows the linear relationship between TGO thickness and phase shift of feature wave. The accurate TOF increment could be acquired from wavelet soft threshold and cross-correlation function with negative effect reduction of environmental noise and system oscillation. Thus, the TGO thickness could be obtained efficiently from the TOF increment of the monitor area with different heating times. The averaged error of 1.61 μm in experimental results demonstrates the highly accurate and robust measurement of the proposed method, making it attractive for condition monitoring and life prediction of TBCs.

关键词: thermal barrier coatings     thermally grown oxide     terahertz spectroscopy     time of flight    

Terahertz time-domain spectroscopy of high-pressure flames

Jason BASSI, Mark STRINGER, Bob MILES, Yang ZHANG

《能源前沿(英文)》 2009年 第3卷 第2期   页码 123-133 doi: 10.1007/s11708-009-0033-x

摘要: Laser spectroscopy in the visible and near infrared is widely used as a diagnostic tool for combustion devices, but this approach is difficult at high pressures within a sooty flame itself. High soot concentrations render flames opaque to visible light, but they remain transparent to far-infrared or terahertz (THz) radiation. The first far-infrared absorption spectra, to the best of our knowledge, of sooty, non-premixed, ethylene high-pressure flames covering the region of 0.2-2.5 THz is presented. A specially designed high-pressure burner which is optically accessible to THz radiation has been built allowing flame transmission measurements up to pressures of 1.6 MPa. Calculations of the theoretical combustion species absorption spectra in the 0.2-3 THz range have shown that almost all the observable features arise from H O. A few OH (1.84 and 2.51 THz), CH (2.58 THz), and NH (1.77 and 2.95 THz) absorption lines are also observable in principle. A large number of H O absorption lines are observed in the ground vibrational in a laminar non-premixed, sooty flame (ethylene) at pressures up to 1.6 MPa.

关键词: terahertz time-domain spectroscopy     high-pressure flames     H2O absorption lines    

Progress in terahertz nondestructive testing: A review

Shuncong ZHONG

《机械工程前沿(英文)》 2019年 第14卷 第3期   页码 273-281 doi: 10.1007/s11465-018-0495-9

摘要: Terahertz (THz) waves, whose frequencies range between microwave and infrared, are part of the electromagnetic spectrum. A gap exists in THz literature because investigating THz waves is difficult due to the weak characteristics of the waves and the lack of suitable THz sources and detectors. Recently, THz nondestructive testing (NDT) technology has become an interesting topic. This review outlines several typical THz devices and systems and engineering applications of THz NDT techniques in composite materials, thermal barrier coatings, car paint films, marine protective coatings, and pharmaceutical tablet coatings. THz imaging has higher resolution but lower penetration than ultrasound imaging. This review presents the significance and advantages provided by the emerging THz NDT technique.

关键词: terahertz pulsed imaging (TPI)     nondestructive testing (NDT)     composite material     thermal barrier coating    

利用太赫兹时域光谱法和微腔器件检测样品:综述 Special Feature on Precision Measurement and Instr

Lin CHEN, Deng-gao LIAO, Xu-guang GUO, Jia-yu ZHAO, Yi-ming ZHU, Song-lin ZHUANG

《信息与电子工程前沿(英文)》 2019年 第20卷 第5期   页码 591-607 doi: 10.1631/FITEE.1800633

摘要: 简要回顾了上海理工大学在用于探测样品的太赫兹时域光谱系统和微腔器件领域的研究进展。首先,通过施加高电场研究了基于砷化镓m-i-n二极管的宽频太赫兹辐射源。然后,详细介绍了我们实验室产生的自由空间太赫兹时域光谱系统和光纤耦合太赫兹时域光谱系统及其在药物/癌症检测中的应用。为进一步提高信噪比和高灵敏度,我们引入3种通用微腔结构实现微量样品检测。本文总结了这些结构的特性、性能和潜在的传感应用。

关键词: 太赫兹时域光谱;微腔;金属孔阵列;波导腔;伪局域表面等离子体    

高精度太赫兹异频回溯天线阵列 Correspondence

Zhong-bo ZHU, Wei-dong HU, Tao QIN, Sheng LI, Xiao-jun LI, Jiang-jie ZENG, Xian-qi LIN, Leo P. LIGTHART

《信息与电子工程前沿(英文)》 2020年 第21卷 第3期   页码 377-383 doi: 10.1631/FITEE.1900581

摘要: 未来通信系统将工作于更高频率,并提供更高传输速率。频率提升将导致难以提供区域宽波束覆盖,因此灵活捷变的波束跟踪将成为技术发展的必然趋势。本文报道的太赫兹波束回溯天线阵列可为灵活捷变的波束跟踪提供良好解决方案。该天线阵列接收40 GHz的导频信号,回溯波束传输的信号是120 GHz。仿真结果表明文中所述具有三明治堆叠结构的天线阵列可成功实现入射波的回溯功能。天线辐射方向图显示该天线阵列在20°入射波条件下,其回溯波束在19.9°位置处,增益为23.87 dB,回溯方向相对误差仅为0.5%。这意味着在5 km传输距离下,水平误差仅为8.7 m。

关键词: 太赫兹;回溯天线阵列;太赫兹通信;共轭混频    

从太赫兹成像到太赫兹无线通信 Review

Yi Huang,Yaochun Shen,Jiayou Wang

《工程(英文)》 2023年 第22卷 第3期   页码 106-124 doi: 10.1016/j.eng.2022.06.023

摘要:

太赫兹(THz)技术是公众熟知的一种强大的成像工具,该技术已经被应用于安全领域和医学扫描,生成了许多使用其他技术所无法获得的令人印象深刻的图像。随着5G移动网络的推出,对6G无线通信的研究正在升温。据预测,太赫兹技术将被用于6G和未来的无线通信。本文回顾了太赫兹技术是如何被应用于成像和无线通信的,然后介绍和确定了该领域的最新发展,最后检查和比较了这两种应用中的常见设备和问题。本文还讨论了将太赫兹成像与无线通信整合的可能性,提出并讨论了目前面临的挑战和未来前景。结果表明,太赫兹技术是未来成像和无线通信的一项关键使能技术。

关键词: 通信     成像     太赫兹技术     无线通信    

Factors influencing near infrared spectroscopy analysis of agro-products: a review

Xiao XU, Lijuan XIE, Yibin YING

《农业科学与工程前沿(英文)》 2019年 第6卷 第2期   页码 105-115 doi: 10.15302/J-FASE-2019255

摘要:

The near infrared (NIR) spectroscopy technique has wide applications in agriculture with the advantages of being nondestructive, sensitive, safe and rapid. However, there are still more than 40 error sources influencing the robustness and accuracy of its calibration and operation. Environmental, sample and instrument factors that influence the analysis are discussed in this review, including temperature, humidity and other factors that introduce uncertainty. Error sources from livestock products, fruit and vegetables, which are the most common objects in the field of NIR analysis, are also emphasized in the second part. In addition, studies utilizing different instruments, spectral pretreatments, variable selection methods, wavelength ranges, detection modes and calibration methods are tabulated to illustrate the complications they introduce and how they influence NIR analysis. It is suggested that large scale of data with abundant varieties can be used to build a more robust calibration model, in order to improve the robustness and accuracy of the NIR analytical model, and overcome problems caused by confining analysis to too many uniform samples.

关键词: agro-product     error source     influence factor     near infrared spectroscopy    

Review: Tip-based vibrational spectroscopy for nanoscale analysis of emerging energy materials

Amun JARZEMBSKI, Cedric SHASKEY, Keunhan PARK

《能源前沿(英文)》 2018年 第12卷 第1期   页码 43-71 doi: 10.1007/s11708-018-0524-8

摘要: Vibrational spectroscopy is one of the key instrumentations that provide non-invasive investigation of structural and chemical composition for both organic and inorganic materials. However, diffraction of light fundamentally limits the spatial resolution of far-field vibrational spectroscopy to roughly half the wavelength. In this article, we thoroughly review the integration of atomic force microscopy (AFM) with vibrational spectroscopy to enable the nanoscale characterization of emerging energy materials, which has not been possible with far-field optical techniques. The discussed methods utilize the AFM tip as a nanoscopic tool to extract spatially resolved electronic or molecular vibrational resonance spectra of a sample illuminated by a visible or infrared (IR) light source. The absorption of light by electrons or individual functional groups within molecules leads to changes in the sample’s thermal response, optical scattering, and atomic force interactions, all of which can be readily probed by an AFM tip. For example, photothermal induced resonance (PTIR) spectroscopy methods measure a sample’s local thermal expansion or temperature rise. Therefore, they use the AFM tip as a thermal detector to directly relate absorbed IR light to the thermal response of a sample. Optical scattering methods based on scanning near-field optical microscopy (SNOM) correlate the spectrum of scattered near-field light with molecular vibrational modes. More recently, photo-induced force microscopy (PiFM) has been developed to measure the change of the optical force gradient due to the light absorption by molecular vibrational resonances using AFM’s superb sensitivity in detecting tip-sample force interactions. Such recent efforts successfully breech the diffraction limit of light to provide nanoscale spatial resolution of vibrational spectroscopy, which will become a critical technique for characterizing novel energy materials.

关键词: vibrational spectroscopy     atomic force microscopy     photo-thermal induced resonance     scanning near-field optical microscopy     tip-enhanced Raman spectroscopy     photo-induced force microscopy     molecular resonances     surface phonon polaritons     energy materials    

Modeling of oil near-infrared spectroscopy based on similarity and transfer learning algorithm

Yifei Wang, Kai Wang, Zhao Zhou, Wenli Du

《化学科学与工程前沿(英文)》 2019年 第13卷 第3期   页码 599-607 doi: 10.1007/s11705-019-1807-2

摘要: Near-infrared spectroscopy mainly reflects the frequency-doubled and total-frequency absorption information of hydrogen-containing groups (O‒H, C‒H, N‒H, S‒H) in organic molecules for near-infrared lights with different wavelengths, so it is applicable to testing of most raw materials and products in the field of petrochemicals. However, the modeling process needs to collect a large number of laboratory analysis data. There are many oil sources in China, and oil properties change frequently. Modeling of each raw material is not only unfeasible but also will affect its engineering application efficiency. In order to achieve rapid modeling of near-infrared spectroscopy and based on historical data of different crude oils under different detection conditions, this paper discusses about the feasibility of the application of transfer learning algorithm and makes it possible that transfer learning can assist in rapid modeling using certain historical data under similar distributions under a small quantity of new data. In consideration of the requirement of transfer learning for certain similarity of different datasets, a transfer learning method based on local similarity feature selection is proposed. The simulation verification of spectral data of 13 crude oils measured by three different probe detection methods is performed. The effectiveness and application scope of the transfer modeling method under different similarity conditions are analyzed.

关键词: near-infrared spectroscopy     transfer learning     similarity     modeling    

Cystine-assisted accumulation of gold nanoparticles on ZnO to construct a sensitive surface-enhanced Raman spectroscopy

《化学科学与工程前沿(英文)》 2023年 第17卷 第1期   页码 15-23 doi: 10.1007/s11705-022-2177-8

摘要: Recently, various semiconductor/metal composites have been developed to fabricate surface-enhanced Raman spectroscopy substrates. However, low metal loading on semiconductors is still a challenge. In this study, cystine was introduced to increase the accumulation of gold nanoparticles on zinc oxide, owing to the biomineralization property of cystine. Morphological analysis revealed that the obtained ZnO/Au/cystine composite not only had a higher metal loading but also formed a porous structure, which is beneficial for Raman performance. Compared with ZnO/Au, the ZnO/Au/cystine substrate displayed a 40-fold enhancement in the Raman signal and a lower limit of detection (10–11 mol·L−1) in the detection of rhodamine 6G. Moreover, the substrate has favorable homogeneity and stability. Finally, ZnO/Au/cystine displayed excellent performance toward crystal violet and methylene blue in a test based on river water samples. This study provided a promising method to fabricate sensitive semiconductor/noble metal-based surface-enhanced Raman spectroscopy substrates for Raman detection.

关键词: biomineralization     cystine     semiconductor/metal composite     SERS detection     Raman detection    

configuration on interface resistances in reverse electrodialysis by in situ electrochemical impedance spectroscopy

《环境科学与工程前沿(英文)》 2022年 第16卷 第4期 doi: 10.1007/s11783-021-1480-9

摘要:

• RED performance and stack resistance were studied by EIS and LSV.

关键词: Reverse electrodialysis     Electrochemical impedance spectroscopy     Concentration polarization     Spacer shadow effect    

用于超快电子器件的全通型波导 Article

Desong Wang, Ke Wu

《工程(英文)》 2023年 第30卷 第11期   页码 49-54 doi: 10.1016/j.eng.2023.04.005

摘要:

Ultrashort pulse transmission has been recognized as a primary problem that fundamentally hinders the development of ultrafast electronics beyond the current nanosecond timescale. This requires a transmission line or waveguide that exhibits an all-pass frequency behavior for the transmitted ultrashort pulse signals. However, this type of waveguiding structure has not yet been practically developed; groundbreaking innovations and advances in signal transmission technology are urgently required to address this scenario. Herein, we present a synthesized all-pass waveguide that demonstrates record guided-wave controlling capabilities, including eigenmode reshaping, polarization rotation, loss reduction, and dispersion improvement. We experimentally developed two waveguides for use in ultrabroad frequency ranges (direct current (DC)-to-millimeter-wave and DC-to-terahertz). Our results suggest that the waveguides can efficiently transmit picosecond electrical pulses while maintaining signal integrity. This waveguide technology is an important breakthrough in the evolution of ultrafast electronics, providing a path towards frequency-engineered ultrashort pulses for low-loss and low-dispersion transmissions.

关键词: All-pass waveguide     Ultrashort pulse     Picosecond transmission     Ultrafast electronics     Terahertz technology     Mode-selective transmission line    

Evidence from sorption kinetics, sequential extraction and extended X-ray absorption fine-structure spectroscopy

《环境科学与工程前沿(英文)》 2022年 第16卷 第9期 doi: 10.1007/s11783-022-1547-2

摘要:

• DPAA sorption followed pseudo-secondary and intra-particle diffusion models.

关键词: Diphenylarsinic acid (DPAA)     Sorption     Magnetite     Siderite     Sequential extraction     EXAFS    

time monitoring of bioreactor mAb IgG3 cell culture process dynamics via Fourier transform infrared spectroscopy

Huiquan Wu, Erik Read, Maury White, Brittany Chavez, Kurt Brorson, Cyrus Agarabi, Mansoor Khan

《化学科学与工程前沿(英文)》 2015年 第9卷 第3期   页码 386-406 doi: 10.1007/s11705-015-1533-3

摘要: Compared to small molecule process analytical technology (PAT) applications, biotechnology product PAT applications have certain unique challenges and opportunities. Understanding process dynamics of bioreactor cell culture process is essential to establish an appropriate process control strategy for biotechnology product PAT applications. Inline spectroscopic techniques for real time monitoring of bioreactor cell culture process have the distinct potential to develop PAT approaches in manufacturing biotechnology drug products. However, the use of inline Fourier transform infrared (FTIR) spectroscopic techniques for bioreactor cell culture process monitoring has not been reported. In this work, real time inline FTIR Spectroscopy was applied to a lab scale bioreactor mAb IgG3 cell culture fluid biomolecular dynamic model. The technical feasibility of using FTIR Spectroscopy for real time tracking and monitoring four key cell culture metabolites (including glucose, glutamine, lactate, and ammonia) and protein yield at increasing levels of complexity (simple binary system, fully formulated media, actual bioreactor cell culture process) was evaluated via a stepwise approach. The FTIR fingerprints of the key metabolites were identified. The multivariate partial least squares (PLS) calibration models were established to correlate the process FTIR spectra with the concentrations of key metabolites and protein yield of in-process samples, either individually for each metabolite and protein or globally for all four metabolites simultaneously. Applying the 2 derivative pre-processing algorithm to the FTIR spectra helps to reduce the number of PLS latent variables needed significantly and thus simplify the interpretation of the PLS models. The validated PLS models show promise in predicting the concentration profiles of glucose, glutamine, lactate, and ammonia and protein yield over the course of the bioreactor cell culture process. Therefore, this work demonstrated the technical feasibility of real time monitoring of the bioreactor cell culture process via FTIR spectroscopy. Its implications for enabling cell culture PAT were discussed.

关键词: process analytical technology (PAT)     Fourier-transform infrared (FTIR) spectroscopy     partial least squares (PLS) regression     mouse IgG3     bioreactor cell culture process     real time process monitoring    

Molecular diffusion in ternary poly(vinyl alcohol) solutions

《化学科学与工程前沿(英文)》 2022年 第16卷 第6期   页码 1003-1016 doi: 10.1007/s11705-021-2121-3

摘要: The diffusion kinetics of a molecular probe—rhodamine B—in ternary aqueous solutions containing poly(vinyl alcohol), glycerol, and surfactants was investigated using fluorescence correlation spectroscopy and dynamic light scattering. We show that the diffusion characteristics of rhodamine B in such complex systems is determined by a synergistic effect of molecular crowding and intermolecular interactions between chemical species. The presence of glycerol has no noticeable impact on rhodamine B diffusion at low concentration, but significantly slows down the diffusion of rhodamine B above 3.9% (w/v) due to a dominating steric inhibition effect. Furthermore, introducing surfactants (cationic/nonionic/anionic) to the system results in a decreased diffusion coefficient of the molecular probe. In solutions containing nonionic surfactant, this can be explained by an increased crowding effect. For ternary poly(vinyl alcohol) solutions containing cationic or anionic surfactant, surfactant–polymer and surfactant–rhodamine B interactions alongside the crowding effect of the molecules slow down the overall diffusivity of rhodamine B. The results advance our insight of molecular migration in a broad range of industrial complex formulations that incorporate multiple compounds, and highlight the importance of selecting the appropriate additives and surfactants in formulated products.

关键词: fluorescence correlation spectroscopy     poly(vinyl alcohol)     anomalous diffusion     crowding effects     dynamic light scattering     binding effects     rhodamine B    

标题 作者 时间 类型 操作

Time of flight improved thermally grown oxide thickness measurement with terahertz spectroscopy

期刊论文

Terahertz time-domain spectroscopy of high-pressure flames

Jason BASSI, Mark STRINGER, Bob MILES, Yang ZHANG

期刊论文

Progress in terahertz nondestructive testing: A review

Shuncong ZHONG

期刊论文

利用太赫兹时域光谱法和微腔器件检测样品:综述

Lin CHEN, Deng-gao LIAO, Xu-guang GUO, Jia-yu ZHAO, Yi-ming ZHU, Song-lin ZHUANG

期刊论文

高精度太赫兹异频回溯天线阵列

Zhong-bo ZHU, Wei-dong HU, Tao QIN, Sheng LI, Xiao-jun LI, Jiang-jie ZENG, Xian-qi LIN, Leo P. LIGTHART

期刊论文

从太赫兹成像到太赫兹无线通信

Yi Huang,Yaochun Shen,Jiayou Wang

期刊论文

Factors influencing near infrared spectroscopy analysis of agro-products: a review

Xiao XU, Lijuan XIE, Yibin YING

期刊论文

Review: Tip-based vibrational spectroscopy for nanoscale analysis of emerging energy materials

Amun JARZEMBSKI, Cedric SHASKEY, Keunhan PARK

期刊论文

Modeling of oil near-infrared spectroscopy based on similarity and transfer learning algorithm

Yifei Wang, Kai Wang, Zhao Zhou, Wenli Du

期刊论文

Cystine-assisted accumulation of gold nanoparticles on ZnO to construct a sensitive surface-enhanced Raman spectroscopy

期刊论文

configuration on interface resistances in reverse electrodialysis by in situ electrochemical impedance spectroscopy

期刊论文

用于超快电子器件的全通型波导

Desong Wang, Ke Wu

期刊论文

Evidence from sorption kinetics, sequential extraction and extended X-ray absorption fine-structure spectroscopy

期刊论文

time monitoring of bioreactor mAb IgG3 cell culture process dynamics via Fourier transform infrared spectroscopy

Huiquan Wu, Erik Read, Maury White, Brittany Chavez, Kurt Brorson, Cyrus Agarabi, Mansoor Khan

期刊论文

Molecular diffusion in ternary poly(vinyl alcohol) solutions

期刊论文