Spectroscopy
Upcoming SlideShare
Loading in...5
×
 

Spectroscopy

on

  • 703 views

 

Statistics

Views

Total Views
703
Views on SlideShare
702
Embed Views
1

Actions

Likes
0
Downloads
12
Comments
0

1 Embed 1

https://bb.dvfu.ru 1

Accessibility

Categories

Upload Details

Uploaded via as Microsoft PowerPoint

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Processing…
Post Comment
Edit your comment

Spectroscopy Presentation Transcript

  • 1. COMPARATIVE STUDY BETWEEN NEARINFRARED(NIR) SPECTROMETERS IN THE MEASUREMENT OF SUCROSE CONCENTRATION
  • 2. INTRODUCTION
  • 3. NIR Spectroscopy I A spectroscopic method that uses the near-infrared region of the electromagnetic spectrum (from about 800 nm to 2500 nm). NIR spectra have only a few significant peaks, but they are exceptionally information-rich due to the number of overlapping absorption bands.
  • 4. NIR Spectroscopy II NIR can typically penetrate much further into a sample than mid infrared radiation due to the low coefficient of absorbance. NIR radiation has less energy/photon but does excite molecular vibrations. NIR measurements are non-destructive and samples are not altered and can be reused.
  • 5. The Importance of Measuring Sugar Concentration in Fruit I Commonly used in the wide range of crops. The important aspect to test the maturity of fruit and obtain the right time to harvest it. The percentage of sugar (oBrix), indicates the sweetness of the fruit.
  • 6. The Importance of Measuring Sugar Concentration in Fruit II Contribute to the calculation of sugar-acid ratio which is one of the step needed to test the maturity of fruit. One critical element of the ripening involves the conversion of starches to sugars. The example of starch test is shown in Figure 1.
  • 7. Objectives 1. To compare response analysis between lower and same range of NIR wavelength (Jaz and QE65000) spectrometer. 2. To identify response analysis of higher range of wavelength (NIRQuest) spectrometer. 3. To compare response analysis between lower and higher range of NIR wavelength spectrometer.
  • 8. Problem Statement The NIR spectrometers are widely used in the spectroscopy field. The calibration transfer between NIR spectrometers should be practiced in spectroscopy field to improve the efficiency in energy, time and work. The comparative study between NIR spectrometers will give huge contribution to the calibration transfer.
  • 9. MATERIALS AND METHOD
  • 10. Apparatus and Material Background I The apparatus used in the experiment are: QE65000 Spectrometer (650 – 1100 nm), Figure 2. NIRQuest512-2.2 Spectrometer (900 – 2200 nm), Figure 3. Handheld Refractometer, Figure 4. The apparatus used in the reference taken: JAZ-COMBO Spectrometer (650 – 1100 nm), Figure 5. *** The characteristics and properties of NIR spectrometers are shown in the Table 1.
  • 11. Apparatus and Material Background II The material used in the experiment is: Sucrose: The molecule is a disaccharide sugar composed of the monosaccharides glucose and fructose with the molecular formula C12H22O11. *** The skeletal formula for sucrose is shown in the Figure 6.
  • 12. Experiment Setup The overall experimental setup was conducted using spectroscopic instrumentations from Ocean Optics. The setup is illustrated in Figure 7. The response was due to mixture between water with sucrose for different type of spectrometer. The characteristics of sucrose sample used in the experiment are tabulated in Table 2.
  • 13. Methodology The flow chart of the experiment is shown in the Figure 8. The experiment was conducted only for the calibration data.
  • 14. RESULTS AND DISCUSSIONS
  • 15. Response Analysis between Jaz and QE65000 Spectrometer I Significant results were managed to be located at wavelength between approximately 940 and 985 nm. Figure 9(a) and Figure 9(b) shows the resultant linear regression generated between absorbance and sucrose concentration by using Jaz and QE65000 spectrometer respectively.
  • 16. Response Analysis between Jaz and QE65000 Spectrometer II λ = 959 nm managed to generate the highest coefficient of determination for sucrose by using: Jaz spectrometer : R2 = 0.9794; RMSE = 1.43 QE65000 spectrometer : R2 = 0.956 ; RMSE = 2.15 The pattern behaviour of linear relationship between absorbance and the sucrose concentration against wavelengths for Jaz and QE65000 spectrometer are shown in Figure 10(a) and Figure 10(b) respectively.
  • 17. Response Analysis between Jaz and QE65000 Spectrometer III It can be seen that the correlation between absorbance and sucrose concentration starts to loose its linearity once it has moved further than 960 nm. Further analysis through the application of Multiple Linear Regression (MLR) has successfully improved the correlation for sucrose measurement.
  • 18. Response Analysis between Jaz and QE65000 Spectrometer IV The highest efficiency algorithm has been identified by using different wavelengths: Jaz spectrometer: 730, 830, 915, and 960 nm QE65000 spectrometer: 909 and 960 nm
  • 19. Response Analysis between Jaz and QE65000 Spectrometer V The calibration algorithm, R2, and RMSE for calibration (RMSEC) for both spectrometers are as follows: Jaz spectrometer: Sucrose concentration (°Brix) = 122 + 1375ƛ730 - 942ƛ830 + 855ƛ915 - 736ƛ960 (R2= 0.992; RMSEC = 0.907 °Brix);
  • 20. Response Analysis between Jaz and QE65000 Spectrometer VI QE65000 spectrometer: Sucrose concentration (°Brix) = 135 + 777ƛ909 - 824ƛ960 (R2= 0.995; RMSEC = 0.760 °Brix) The linearity of the calculated model are illustrated in Figure 11(a) and Figure 11(b) for Jaz spectrometer and QE65000 spectrometer respectively.
  • 21. Response Analysis of NIRQuest Spectrometer I Significant result is managed to be located at wavelength between approximately 980 and 1700 nm. Figure 12 shows the resultant linear regression generated between absorbance and sucrose concentration by using NIRQuest spectrometer.
  • 22. Response Analysis of NIRQuest Spectrometer II λ = 1363 nm managed to generate the highest coefficient of determination and lowest RMSE for sucrose by using: NIRQuest spectrometer : R2 = 0.813; RMSE = 4.64 The pattern behaviour of linear relationship between absorbance and the sucrose concentration against wavelengths for NIRQuest spectrometer is shown in Figure 13.
  • 23. Response Analysis of NIRQuest Spectrometer III The correlation between absorbance and sucrose concentration starts to loose its linearity once it has moved further than 1400 nm. Further analysis through the application of Multiple Linear Regression (MLR) has successfully improved the correlation for sucrose measurement.
  • 24. Response Analysis of NIRQuest Spectrometer IV The highest efficiency algorithm has been identified by using different wavelengths: NIRQuest spectrometer : 980, 1156, 1163, 1195, 1337, 1350, 1395, 1606, 1670, 1676, and 1682 nm.
  • 25. Response Analysis of NIRQuest Spectrometer V The following are the calibration algorithm, R2, and RMSEfor calibration (RMSEC): NIRQuest spectrometer Sucrose concentration (°Brix) = 171 + 79ƛ980 + 2909ƛ1156 - 1550ƛ1163 - 422ƛ1195 + 445ƛ1337 - 1783ƛ1350 + 310ƛ1395 – 41.8ƛ1606 + 298ƛ1670 298ƛ1676 + 195ƛ1682 (R2 = 0.982; RMSEC = 1.613 °Brix) The linearity of the calculated model is illustrated by Figure 14.
  • 26. Response Analysis between NIR Spectrometers I By comparing the three spectrometers, all of them show the same properties : The absorption of a specific range of NIR wavelength decreases linearly with the increases of sucrose concentration. Further analysis through MLR has successfully improved the correlation for sucrose measurement.
  • 27. Response Analysis between NIR Spectrometers II The ascending order of highest coefficient determination produced are by using NIRQuest, Jaz, and QE65000 spectrometers.
  • 28. CONCLUSIONS AND RECOMMENDATIONS
  • 29. Conclusions I Wavelength that generate the highest coefficient of determination : Jaz spectrometer: 959 nm (R2 = 0.9794; RMSE = 1.43) QE65000 spectrometer : 959 nm (R2 = 0.956 ; RMSE = 2.15) NIRQuest spectrometer : 1363 nm (R2 = 0.813; RMSE = 4.64)
  • 30. Conclusions II Combination of NIR wavelength that produce the highest coefficient of determination: Jaz spectrometer : ƛ=730, 830, 915, and 960 nm (R2= 0.992; RMSEC = 0.907) QE65000 spectrometer : ƛ=909 and 960 nm (R2= 0.995; RMSEC = 0.760)
  • 31. Conclusions III NIRQuest spectrometer : ƛ=980, 1156, 1163, 1195, 1337, 1350, 1395, 1606, 1670, 1676, and 1682 nm (R2 = 0.982; RMSEC = 1.613) These wavelengths exert an important combination in development of calibration algorithm for individual spectrometer measurement.
  • 32. Recommendations For future experiment : record the validation data as well in order to confirm the prediction. conduct the experiment by using the sugar content in fruit to obtain the real experience on how to improve the intrinsic quality of fruit.
  • 33. Figure 1 : The Example of Starch Test
  • 34. Figure 2 : QE65000 Spectrometer
  • 35. Figure 3 : NIRQuest512-2.2 Spectrometer
  • 36. Figure 4 : Handheld Refractometer
  • 37. Figure 5 : Jaz Spectrometer
  • 38. Table 1 :The characteristics and properties of NIR spectrometers. Jaz QE65000 NIRQuest Characteristics -Modular, stackable and autonomous components -Czemy-Turner optical bench -On-board microprocessor and OLED display -Replaceable slits and gratings -Ethemet and memory module -Battery and external memory module -200-1100 nm spectral rangegrating dependent -Resolution 0.14-7.7 nm (FWHM) -Peak quantum efficiency 90% -Back thinned 2DCCD detector -Thermoelectric cooling -6 slit options -14 grating option -900-2050 nm spectral range -Less than 1 nm optical resolution FWHM -15000:1 signal to noise -On board thermoelectric cooling -16 bit USB A/D converter -Crossed czemy-Turner optical bench -Various trigger modest grating options Application -Fluorescence -Biotechnology -Raman spectroscopy -DNA sequencing -Remote sensing -Dosimetry -Spectroscopy -Medical -Biomedical imaging analysis -Fluorescence -Luminescence detection -Luminescence detection -Spectroscopy of emission and absorption lines spectroscopy
  • 39. Figure 6 : Skeletal Formula for Sucrose
  • 40. Figure 7 : Experiment Setup for NIR Measurement (Top view)
  • 41. Table 2 :The Sample Characteristics. Spectrometer Range of Sucrose Mean (°Brix) n (Calibration) Jaz 0.9-35.0 17.1 50 QE65000 0.1-39.1 8.8 50 0.2-38.8 18.8 50 NIRQuest512-2.2
  • 42. Apparatus setup Data analysis Sample preparation Repeat experiment with other spectrometer Collect reference spectrum Save data obtained Reduce concentratio n of sucrose until 50 data Figure 8 : Flow Chart of Experiment
  • 43. 0.12 y = -0.001394x + 0.1193; R-Sq = 0.9794 Absorbance 0.11 0.10 0.09 0.08 0.07 0 10 20 30 40 Sucrose Conce ntration (Brix) Figure 9(a) : Linear relationship between absorbance and concentration of aqueous sucrose at λ = 959 nm by using Jaz spectrometer
  • 44. 0.165 y = - 0.000714x + 0.1645 0.160 Absorbance 0.155 0.150 0.145 0.140 0.135 0.130 0 10 20 30 40 Sugars conce ntration (Brix) Figure 9(b) : Linear relationship between absorbance and concentration of aqueous sucrose at λ = 959 nm by using QE65000 spectrometer
  • 45. 1.1 Coefficient of Determination 1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 920 930 940 950 960 970 980 990 1000 1010 Wave le ngth (nm) Figure 10(a) : Coefficient of determination generated at different wavelength for aqueous sucrose concentration by using Jaz spectrometer
  • 46. Coefficient of Determination 1.0 0.8 0.6 0.4 0.2 0.0 920 930 940 950 960 970 980 990 1000 1010 Wave le ngth (nm) Figure 10(b) : Coefficient of determination generated at different wavelength for aqueous sucrose concentration by using QE65000 spectrometer
  • 47. Calculated Concentration (Brix) 35 30 25 20 15 10 5 0 0 5 10 15 20 25 30 35 Actual Conce ntration (Brix) Figure 11(a) : Calculated VS actual concentrations of sucrose by using Jaz spectrometer.
  • 48. Calculated Concentration (Brix) 40 35 30 25 20 15 10 5 0 0 5 10 15 20 25 30 35 40 Actual Conce ntration (Brix) Figure 11(b) : Calculated VS actual concentrations of sucrose by using QE65000 spectrometer.
  • 49. 1.30 Absorbance 1.25 y = - 0.006183x + 1.300 1.20 1.15 1.10 1.05 0 10 20 30 40 Sucrose Conce ntration (Brix) Figure 12 : Linear relationship between absorbance and concentration of aqueous sucrose at λ = 1363 nm by using NIRQuest spectrometer.
  • 50. 0.9 Coefficient of Determination 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 1000 1100 1200 1300 1400 1500 1600 Wave le ngth (nm) Figure 13 : Coefficient of determination generated at different wavelengths for aqueous sucrose concentration by using NIRQuest spectrometer.
  • 51. Calculated Concentration (Brix) 40 30 20 10 0 0 10 20 30 40 Actual Conce ntration (Brix) Figure 14 : Calculated VS actual concentrations of sucrose by using NIRQuestspectrometer.