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Characterization and evaluation of oil shale based on Terahertz spectroscopy: A review

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Energy Reviews

Energy Reviews 2023年第4期2卷 1-11页

作者： Xuecong Liu Kun Zhao Xinyang Miao Honglei Zhan College of Information Science and Technology China University of PetroleumBeijing102249China College of New Energy and Materials China University of PetroleumBeijing102249China Beijing Key Laboratory of Optical Detection Technology for Oil and Gas China University of PetroleumBeijing102249China Key Laboratory of Oil and Gas Terahertz spectroscopy and Photoelectric Detection Petroleum and Chemical Industry FederationChina University of PetroleumBeijing102249China

Oil shale is a fine-grained sedimentary rock rich in organic kerogen,which is a national strategic reserve resource and supplementary energy and shale oil and pyrolysis gas can be obtained through carbonization and pyrolysis.Due to the diversity of main components in oil shale and the complexity of the occurrence relationship between organic matter and minerals,the current understanding of the oil generation potential of oil shale and the dy-namic process of organic matter pyrolysis is still unclear,leading to the relatively backward level of its devel-opment technology.The development of new theories and methods for efficient utilization of oil shale resources has great strategic significance.The rotation and vibration frequency of macromolecules in oil shale occur in the terahertz(THz)band,so the THz optical parameters of oil shale can reflect the physical properties of kerogen.In this review,the experimental work progress in THz spectroscopy for characterization and evaluation of oil shale is provided.Oil shale is high anisotropic,resulting that the anisotropy in THz optical parameters strongly depends on the oil yield which is an effective selection for evaluating the oil yield to avoid the problem of environmental pollution in traditional detection.The heterogeneous distributions of organics on the oil shale surface,e.g.,the existence of kerogen-rich and kerogen-poor areas,was evaluated by THz amplitude imaging.In addition,the thermal THz analysis technology was developed to determine the pyrolysis process of kerogen and establish the pyrolysis model of kerogen,and the optimization of oil shale pyrolysis process was realized using THz parameters.Moreover,kerogen in oil shale displays a characteristic absorption peak in the THz range,which provides a new insight into the research of kerogen in the micro and nano scale.The pyrolysis oil shale at high temperature absorbs THz radiation strongly due to the decomposition of pyrite in oil shale.These recent works suggest that THz spectroscopy can realize rapid and

关键词： Oil shale Terahertz spectroscopy Kerogen Anisotropy Yield Pyrolysis Absorption

Feasibility of Terahertz spectroscopy for hybrid purity verification of rice seeds

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International Journal of Agricultural and Biological Engineering 2018年第5期11卷 65-69页

作者： Yaling Yang Shengling Zhou Jie Song Jie Huang Guanglin Li Shiping Zhu College of Physical Science and Technology Southwest UniversityChongqing 400715China College of Engineering and Technology Southwest UniversityChongqing 400715China

The purity of hybrid rice seeds reflects the typical consistency of seed varieties in characteristics.The accuracy and reliability of seed purity detecting are of great significance to ensure the quality of seeds.In this study,the feasibility of identifying the purity of hybrid rice seeds,Xinong 1A/89,by terahertz(THz)time-domain spectroscopy system combined with chemometrics was explored.Three quantitative identification models for testing the purity of Xinong 1A/89 hybrid rice seed were developed and compared by THz absorption spectroscopy with extreme learning algorithm(ELM),Principal cComponent Regression(PCR)and Partial Least Squares Regression(PLSR).Experimental results showed that comparing with classical PLSR and PCR models,ELM presents a better feasibility and stability.For the testing set,the quantitative prediction result of ELM(ELoo=2.005×10^(-5),R^(2)=96.75%)is significantly better than those of PCR(ELoo=7.346×10^(-5),R^(2)=88.10%)and PLSR(ELoo=8.007×10^(-5),R^(2)=87.03%).The results highlight the feasibility of THz spectroscopy combined with ELM as an efficient and reliable method for verification of hybrid rice seeds.

关键词： purity detection hybrid rice seeds Terahertz spectroscopy extreme learning algorithm

Measurements and analysis of water content in winter wheat leaf based on Terahertz spectroscopy

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International Journal of Agricultural and Biological Engineering 2018年第3期11卷 178-182页

作者： Bin Li Yuan Long Hao Yang Beijing Research Center for Information Technology in Agriculture Beijing 100097China Beijing Key Laboratory of Digital Plant Beijing 100097China Beijing Research Center of Intelligent Equipment for Agriculture Beijing 100097China Key Laboratory of Quantitative Remote Sensing in Agriculture of Ministry of Agriculture Beijing 100097China

Wheat is a major grain crop in China.Water is one of the most important factors which influence the lifecycle and yield of wheat.It is of great significance to study the water content at the key stages of wheat growth in order to make irrigation decision to raise its yield.As terahertz(THz)spectroscopy is a brand new sensing technology and sensitive to water absorption,the relationship between terahertz spectra and water content in winter wheat leaf was investigated and a preliminary result was presented in this paper.Forty winter wheat leaves samples with diverse range of water content(42.8%-72.5%)were collected.The terahertz time domain spectra(THz-TDS)were first obtained and then transformed into Frequency-domain amplitude with the Fast Fourier Transformation(FFT)method.The absorption and refractive index spectra were then calculated.The spectra were linearly fitted to obtain the slope and intercept used for building a calibration model.The partial least squares(PLS)method and linear regression were employed to establish models to determine leaf water content in the winter wheat.The predicted correlation coefficient and the root mean square error of the optimal model established with the Frequency-domain amplitude parameter at 0.3 THz by linear regression were 0.812%and 4.4%,respectively.The results showed that Terahertz spectroscopy performed well in water content prediction and could be an effective and potential method for leaf water content measurement in winter wheat.

关键词： Terahertz spectroscopy winter wheat gravimetric water content(GWC) partial least squares method

Tunable near- to mid-infrared pump terahertz probe spectroscopy in reflection geometry

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Frontiers of physics 2017年第5期12卷 81-85页

作者： S. J. Zhang Z. X. Wang T. Dong N. L. Wang International Center for Quantum Materials School of Physics Peking University Beijing 100871 China Collaborative Innovation Center of Quantum Matter Beijing 100871 China

Strong-field mid-infrared pump-terahertz （THz）probe spectroscopy has been proven as a powerful tool for light control of different orders in strongly correlated materials. We report the construction of an ultrafast broadband infrared pump-THz probe system in reflection geometry. A two-output optical parametric amplifier is used for generating mid-infrared pulses with GaSe as the nonlinear crystal. The setup is capable of pumping bulk materials at wavelengths ranging from 1.2 μm to 15 μm and beyond, and detecting the subtle, transient photoinduced changes in the reflected electric field of the THz probe at different temperatures. As a demonstration, we present 15 μm pump-THz probe measurements of a bulk EuSbTe3 single crystal. A 0.5% transient change in the reflected THz electric field can be clearly resolved. The widely tuned pumping energy could be used in mode-selective excitation experiments and applied to many strongly correlated electron systems.

关键词： mid-infrared pump Terahertz spectroscopy

Preliminary study on qualitative and quantitative detection of norfloxacin based on Terahertz spectroscopy

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International Journal of Agricultural and Biological Engineering 2017年第5期10卷 262-268页

作者： Long Yuan Li Bin Beijing Research Center for Information Technology in Agriculture Beijing 100097China Key Laboratory of Agri-informatics Ministry of AgricultureBeijing 100097China Beijing Key Laboratory of Digital Plant Beijing 100097China

Norfloxacin is a kind of quinolone bactericide which is widely used in food industry,livestock feed and medicine area.At present,how to develop a rapid,convenient and accurate technique for qualitative and quantitative detection of norfloxacin is still a challenge.In this study,terahertz Time-domain spectroscopy technology(THz-TDS)was used to explore qualitative and quantitative analysis of norfloxacin.Forty-five norfloxacin samples with different levels were prepared.The pure norfloxacin powder was mixed with polyethylene(PE)powder together and made into tablets by tablet-making machine.The minimum detection concentration was 10%and the maximum detection concentration evaluated in the paper was 90%.Then,terahertz(THz)spectra of each sample were measured on K15 THz-TDS equipment.The multiple linear regressions and the partial least squares regression algorithms were used to establish a model to make quantitative analysis.From the results,two typical fingerprint peaks of norfloxacin in terahertz band were observed at 0.944 THz and 1.206 THz,and the correlation coefficient and the root mean square error of the established model reached 0.9908 and 0.0481,respectively,which showed that the model performed well for the prediction.This preliminary study indicates that THz spectroscopy has great potential for future screening applications to detect the presence of norfloxacin residues in food,livestock feed and medicine industries.

关键词： Terahertz spectroscopy norfloxacin qualitative and quantitative detection model correlation coefficient

Leakage detection of oil tank using Terahertz spectroscopy

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Science China(Technological Sciences) 2021年第9期64卷 1947-1952页

作者： QIN FanKai CHEN SiTong CHEN Ru ZHAN HongLei MIAO XinYang XIANG WenFeng ZHAO Kun College of New Energy and Materials China University of PetroleumBeijing 102249China Beijing Key Laboratory of Optical Detection Technology for Oil and Gas China University of PetroleumBeijing 102249China Key Laboratory of Oil and Gas Terahertz spectroscopy and Photoelectric Detection Petroleum and Chemical Industry FederationChina University of PetroleumBeijing 102249China Detection and Beijing Key Laboratory of Failure Corrosionand Protection of Oil/Gas FacilitiesChina University of PetroleumBeijing 102249China

The necessity for safety in oil-gas storage and transportation has led to increasing technical requirements for on-line monitoring of damaged pores and oil leakage from tanks. In this study, the severity of damage of the oil tank at the micron level was detected by terahertz time-domain spectroscopy(THz-TDS), which is of great significance for the early detection and prevention of oil leakage. The THz amplitude(EP) was related to the severity of damaged according to the THz-TDS measurement of oil tanks with various degrees of damage, including intact, partially damaged, completely damaged, and seriously damaged points.Absorption and scattering effects co-occurred when the THz wave penetrated the tanks, with the collective tendencies being used to expressly monitor oil leakage from tanks. When the oil tank was damaged to form micron-level pores and the crude oil had not overflowed, the pore size was close to THz wavelength and the Mie scattering effect was obvious. After further destruction of the pores, the crude oil gradually spilled over and the scattering effect was gradually transformed from Mie scattering to Rayleigh scattering. In addition, the polar molecules in crude oil have strong resonance under the irradiation of THz wave, and the THz wave has strong attenuation. Eventually, surface tension of the oil flattens the surface of the tank, the scattering effect is gradually suppressed and replaced by the absorption effect. Absorption and scattering caused by THz waves passing through tanks coexist and have competing relationships. The change rule of EPcan successfully prove the phenomenon and can be considered as an important alternative for application to predict the degree of tank damage. Therefore, in this study, the detection of pores as small as micrometers on the oil tank was expected to greatly prevent oil leakage accidents and improve the safety of oil and gas storage and transportation.

关键词： absorption scattering Terahertz spectroscopy oil tank leakage

Measurement Method of Internal Residual Stress in Plastic Parts Using Terahertz spectroscopy

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Nanomanufacturing and Metrology 2021年第1期4卷 46-52页

作者： Yusuke Kajihara Rio Takahashi Ichiro Yoshida Shingo Saito Norihiko Sekine Shuichi Nowatari Shigeo Miyake Institute of Industrial Science The University of TokyoKomaba 4-6-K Meguro-kuTokyoJapan Hosei University Kajino 3-7-2.KoganeiTokyoJapan National Institute of Information and Communications Technology Nukui-Kitamachi 4-2-1KoganeiTokyoJapan Iida Co. LtdNukazawa Mizukami 21-2MotomiyiaFukushimaJapan

Since internal residual stress in polymers causes dimension errors over time,a measurement method for residual stress in polymers,especially in opaque engineering plastics,is strongly required.In this study,we propose to utilize terahertz(THz)spectroscopy to non-destructively measure internal residual stress in polymers.To verify the validity of the proposed method,we manufactured polytetrafluoroethylene ring samples with and without residual stress,and studied them with THz time domain spectroscopy system.THz spectra of samples without residual stress showed almost no polarization difference,whereas spectra of samples with residual stress showed clear polarization difference.Dimension changes between the samples with and without residual stress were also estimated and it was found that the change had a correlation with THz polarization difference.These experimental analyses confirm the validity for the proposed non-destructive measurement of residual stress in polymer.

关键词： Engineering plastics Residual stress Polarization Terahertz spectroscopy

Time-Resolved Terahertz spectroscopy with Free-Space Electro-Optic Sampling

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Chinese Physics Letters 2004年第11期21卷 2295-2297页

作者：张亮亮赵国忠钟华胡颖张存林 LDepartmentofPhysics CapitalNormalUniversityBeijing100037 RensselaerPolytechnicInstitute NewYorkUSA

We present a time-resolved ultrafast measurement in terahertz (THz) frequency region by means of the free-space electro-optic sampling. The fast delay scan technique is used to suppress the noise with low frequency and to improve the signal-to-noise ratio of the system. The transmission spectra of different materials are obtained. The optical properties of these materials in a THz region are shown. The broadening of spectrum and chirping phenomena are illustrated. We find that polystyrene is an excellent material for the THz application.

关键词： Terahertz spectroscopy

terahertz Vibrational spectroscopy in Molecular Crystalline Systems

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Terahertz Vibrational Spectroscopy in Molecular Crystalline ...