Absorbance Peak

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Murray J. Thomson - One of the best experts on this subject based on the ideXlab platform.

  • High-Temperature H2O Vapor Measurement Using Terahertz Spectroscopy for Industrial Furnace Applications
    IEEE Transactions on Terahertz Science and Technology, 2016
    Co-Authors: Yuhui Song, Zhenyou Wang, Murray J. Thomson
    Abstract:

    We verified that high-temperature (773 K) H2O vapor can be measured quantitatively with terahertz (THz) spectroscopy in the frequency range of 0.5-0.8 THz. The linear relationships between the Absorbance Peak area and the H2O vapor volume mixing ratio (VMR) at three absorption Peaks (0.557 THz, 0.658 THz, and 0.752 THz) match HITRAN-based simulations closely, which indicates that the HITRAN database can be used for practical applications. Particularly, since the Peak at 0.658 THz only appears at high temperatures, it can be used to measure high-temperature H2O vapor directly in the presence of room-temperature ambient H2O vapor.

  • Measuring Gas Temperature in Highly Particle Laden Flow Using Terahertz Spectroscopy
    IEEE Transactions on Terahertz Science and Technology, 2016
    Co-Authors: Zhenyou Wang, Murray J. Thomson
    Abstract:

    We developed two methods to use terahertz (THz) spectroscopy to perform gas temperature measurement: using the area ratio of two H2O vapor Absorbance Peaks, and using the relative time delay of the THz signal, both of which change as a function of temperature. Both methods can be used in situations with high particle loading that would block traditional laser signals and degrade thermocouple performance, as THz signals do not attenuate due to particle scattering. The Absorbance Peak ratios were tested in the frequency range of 0.5-0.8 THz at temperatures of 523-773 K. The relationship between the gas temperature and line strength ratio of the Peaks match those calculated using the HITRAN database, but has high uncertainty due to THz source instability. The time delay was tested at a frequency of 0.5 THz and temperatures of 293-773 K, and is used to determine temperature by calculating the index of refraction of the gas. It is a more accurate method, but requires knowledge of the gas composition.

Nuru Saniyyati C M Shukri - One of the best experts on this subject based on the ideXlab platform.

  • new near infrared Absorbance Peak for inhibitor content detection in transformer insulating oil
    Sensors and Actuators B-chemical, 2018
    Co-Authors: Yang Sing Leong, M Z Jamaludin, Saifuddin M Nomanbhay, A Ismail, F Abdullah, Hui Mun Looe, Nuru Saniyyati C M Shukri
    Abstract:

    Abstract Monitoring the condition of transformer insulating oil has been considered as a crucial and effective measure for preventive maintenance of power transformers. Various properties of the oil can be monitored such as the dissolved gases, furan content, and inhibitor content. This paper focuses on the inhibitor content in insulating oil. Currently, Fourier transform infrared (FTIR) spectroscopy in accordance with the IEC 60666 standard is used for the measurement of inhibitor concentration in insulating oil. However, this technique involves site sampling, transportation to a laboratory and an expensive instrument. This work proposes the characterization of inhibitor content in insulating oil in the near-infrared (NIR) waveband, which would lead to the design of a faster and cheaper detection system for inhibitor content. It was found that the inhibitor content exhibits an optical Absorbance Peak at 1403 nm, which was not reported in any previous work. A mathematical model was then created to describe the relationship between the concentration of inhibitor, the area under the Absorbance spectrum and the Peak optical Absorbance. The model was verified, and the results showed a root mean square error (RMSE) of 0.0458.

Yang Sing Leong - One of the best experts on this subject based on the ideXlab platform.

  • new near infrared Absorbance Peak for inhibitor content detection in transformer insulating oil
    Sensors and Actuators B-chemical, 2018
    Co-Authors: Yang Sing Leong, M Z Jamaludin, Saifuddin M Nomanbhay, A Ismail, F Abdullah, Hui Mun Looe, Nuru Saniyyati C M Shukri
    Abstract:

    Abstract Monitoring the condition of transformer insulating oil has been considered as a crucial and effective measure for preventive maintenance of power transformers. Various properties of the oil can be monitored such as the dissolved gases, furan content, and inhibitor content. This paper focuses on the inhibitor content in insulating oil. Currently, Fourier transform infrared (FTIR) spectroscopy in accordance with the IEC 60666 standard is used for the measurement of inhibitor concentration in insulating oil. However, this technique involves site sampling, transportation to a laboratory and an expensive instrument. This work proposes the characterization of inhibitor content in insulating oil in the near-infrared (NIR) waveband, which would lead to the design of a faster and cheaper detection system for inhibitor content. It was found that the inhibitor content exhibits an optical Absorbance Peak at 1403 nm, which was not reported in any previous work. A mathematical model was then created to describe the relationship between the concentration of inhibitor, the area under the Absorbance spectrum and the Peak optical Absorbance. The model was verified, and the results showed a root mean square error (RMSE) of 0.0458.

Zhenyou Wang - One of the best experts on this subject based on the ideXlab platform.

  • High-Temperature H2O Vapor Measurement Using Terahertz Spectroscopy for Industrial Furnace Applications
    IEEE Transactions on Terahertz Science and Technology, 2016
    Co-Authors: Yuhui Song, Zhenyou Wang, Murray J. Thomson
    Abstract:

    We verified that high-temperature (773 K) H2O vapor can be measured quantitatively with terahertz (THz) spectroscopy in the frequency range of 0.5-0.8 THz. The linear relationships between the Absorbance Peak area and the H2O vapor volume mixing ratio (VMR) at three absorption Peaks (0.557 THz, 0.658 THz, and 0.752 THz) match HITRAN-based simulations closely, which indicates that the HITRAN database can be used for practical applications. Particularly, since the Peak at 0.658 THz only appears at high temperatures, it can be used to measure high-temperature H2O vapor directly in the presence of room-temperature ambient H2O vapor.

  • Measuring Gas Temperature in Highly Particle Laden Flow Using Terahertz Spectroscopy
    IEEE Transactions on Terahertz Science and Technology, 2016
    Co-Authors: Zhenyou Wang, Murray J. Thomson
    Abstract:

    We developed two methods to use terahertz (THz) spectroscopy to perform gas temperature measurement: using the area ratio of two H2O vapor Absorbance Peaks, and using the relative time delay of the THz signal, both of which change as a function of temperature. Both methods can be used in situations with high particle loading that would block traditional laser signals and degrade thermocouple performance, as THz signals do not attenuate due to particle scattering. The Absorbance Peak ratios were tested in the frequency range of 0.5-0.8 THz at temperatures of 523-773 K. The relationship between the gas temperature and line strength ratio of the Peaks match those calculated using the HITRAN database, but has high uncertainty due to THz source instability. The time delay was tested at a frequency of 0.5 THz and temperatures of 293-773 K, and is used to determine temperature by calculating the index of refraction of the gas. It is a more accurate method, but requires knowledge of the gas composition.

M Z Jamaludin - One of the best experts on this subject based on the ideXlab platform.

  • new near infrared Absorbance Peak for inhibitor content detection in transformer insulating oil
    Sensors and Actuators B-chemical, 2018
    Co-Authors: Yang Sing Leong, M Z Jamaludin, Saifuddin M Nomanbhay, A Ismail, F Abdullah, Hui Mun Looe, Nuru Saniyyati C M Shukri
    Abstract:

    Abstract Monitoring the condition of transformer insulating oil has been considered as a crucial and effective measure for preventive maintenance of power transformers. Various properties of the oil can be monitored such as the dissolved gases, furan content, and inhibitor content. This paper focuses on the inhibitor content in insulating oil. Currently, Fourier transform infrared (FTIR) spectroscopy in accordance with the IEC 60666 standard is used for the measurement of inhibitor concentration in insulating oil. However, this technique involves site sampling, transportation to a laboratory and an expensive instrument. This work proposes the characterization of inhibitor content in insulating oil in the near-infrared (NIR) waveband, which would lead to the design of a faster and cheaper detection system for inhibitor content. It was found that the inhibitor content exhibits an optical Absorbance Peak at 1403 nm, which was not reported in any previous work. A mathematical model was then created to describe the relationship between the concentration of inhibitor, the area under the Absorbance spectrum and the Peak optical Absorbance. The model was verified, and the results showed a root mean square error (RMSE) of 0.0458.

  • Determining the inhibitor content of transformer insulating oil using UV-Vis spectroscopy
    2016 6th IEEE International Conference on Control System Computing and Engineering (ICCSCE), 2016
    Co-Authors: Leong Yang Sing, M Z Jamaludin, A Ismail, F Abdullah, Nuru C. Saniyyat, M. Shukri
    Abstract:

    Monitoring and inspection of inhibitor content in transformer insulating oil has been a routine test for power utilities. Although new uninhibited transformer insulating oil contains naturally occurring inhibitors, these inhibitors could deplete over time during operation. Once the inhibitor depleted completely, the oil would start to deteriorate at a faster rate and eventually could lead to faults in transformer. The common method of determining the weight percentage of inhibitor in transformer oil is through Fourier Transform Infrared (FTIR) spectroscopy. However, this method is laboratory-based, which means oil sampling at site is necessary and the oil samples need to be transported to the laboratory. The necessity for oil sampling, coupled with the high cost of FTIR equipment have led to high maintenance cost. Therefore, this work investigated the possibility of using single wavelength or waveband optical detection for the determination of weight percentage of inhibitor in transformer oil using ultraviolet-visible-near infrared (UV-VIS-NIR) spectroscopy. Result of the work shows that the samples with inhibitor produced an Absorbance Peak at 1403nm. The Peak Absorbance of the spectral response is proportional to the weight percentage of inhibitor content that was measured using the conventional method, which is IEC 60666. An equation was derived to model the Peak Absorbance and weight percent of inhibitor content (%IC) of the oil and it was verified with additional oil sample with a known weight percent of Inhibitor content.