Analysis of the Scattering Properties of Granular Materials

1997 ◽  
Vol 5 (3) ◽  
pp. 123-133 ◽  
Author(s):  
Céline Ventura ◽  
Marie Papini
Keyword(s):  
Granular Materials ◽  
Near Infrared ◽  
Diffuse Reflectance Spectroscopy ◽  
Statistical Treatment ◽  
Principal Component ◽  
Physical Nature ◽  
Inorganic Materials ◽  
Absorption Bands ◽  
Infrared Wavelength ◽  
Cross Correlation Analysis

The present study concerns diffuse reflectance spectroscopy of polymer powders and of their binary mixtures with inorganic materials. The total near-normal hemispherical spectral reflectance R of granular materials was measured in the near infrared wavelength range with a dispersive spectrophotometer. The measurement of the reflectance illustrated the influence of different parameters by taking into account (a) the morphology: powders or pellets and (b) the optical property of the material: semi-transparent, opaque or reflecting powders. The statistical treatment of the reflectance data by principal component analysis (PCA) allowed these data to be displayed in a reduced dimensionality space. As a result, the clustering of samples related to their chemical or their physical nature was carried out, giving a simpler description of the data in a new representation. The cross-correlation analysis of the reflectance values allowed similarities between absorption bands to be highlighted.

Study on Identification Method of 'Pingli' Gynostemma with Near-Infrared Spectroscopy

2013 ◽  
Vol 781-784 ◽  
pp. 1464-1468
Author(s):  
Xiu Hua Liu ◽  
Xiao Ting Li ◽  
Jing Wang ◽  
Rui Ying Li ◽  
Guang Chen Wu ◽  
...  
Keyword(s):  
Principal Component Analysis ◽  
Cluster Analysis ◽  
Infrared Spectroscopy ◽  
Near Infrared Spectroscopy ◽  
Near Infrared ◽  
Diffuse Reflectance Spectroscopy ◽  
Principal Component ◽  
Component Analysis ◽  
Qualification Testing ◽  
And Cluster Analysis

In order to identify the authentic Pingli Gynostemma, a geographical indication products, diffuse reflectance spectroscopy of Gynostemma came from eight different origins were collected by the Fourier near-infrared spectrometer. The spectroscopy was analyzed with Chemometrics method, and the spectroscopy was pretreated by the vector normalization condition. The range of spectra was 4800-10096 cm-1. The Calibration models of Gynostemma were established by the principal component analysis, qualification testing and cluster analysis, respectively, and each model was verified. The results show that the optimal model established by the principal component analysis, qualification testing and cluster analysis can effectively identify authentic Pingli Gynostemma, and accuracy rate was 100%. In conclusion, Pingli Gynostemma can be identified accurately and quickly by the near-infrared spectroscopy technique.

Study on Identification Method of Zherong Radix Pseudostellariae with Near-Infrared Spectroscopy

2014 ◽  
Vol 989-994 ◽  
pp. 4028-4031
Author(s):  
Yan Ping Pang ◽  
Kun Liu ◽  
Li Ya Xia ◽  
Shao Long Yu
Keyword(s):  
Principal Component Analysis ◽  
Cluster Analysis ◽  
Infrared Spectroscopy ◽  
Near Infrared Spectroscopy ◽  
Near Infrared ◽  
Diffuse Reflectance Spectroscopy ◽  
Principal Component ◽  
Component Analysis ◽  
Qualification Testing ◽  
And Cluster Analysis

In order to identify the Zherong Radix Pseudostellariae, a geographical indication products, diffuse reflectance spectroscopy of came from ten different origins were collected by the Fourier near-infrared spectrometer. The spectroscopy was analyzed with Chemometrics method,and the spectroscopy was pretreated by the second derivative, first derivation and minus a straight line condition. The range of spectra was 3996.1-7282.5 cm-1. The Calibration models of Radix Pseudostellariae were established by the qualification testing, principal component analysis, and cluster analysis respectively, and each model was verified. The results show that the optimal model established by the qualification testing, principal component analysis and cluster analysis can effectively identify authentic Zherong Radix Pseudostellariae , and accuracy rate was more than 97.5%. In conclusion, Zherong Radix Pseudostellariae can be identified accurately and quickly by the near-infrared spectroscopy technique.

scholarly journals Prediction of Soil Texture Distributions by using PLSR and Reflectance Spectroscopy

2019 ◽  
Vol 8 (3) ◽  
pp. 7876-7881
Keyword(s):  
Statistical Analysis ◽  
Soil Texture ◽  
Near Infrared ◽  
Diffuse Reflectance Spectroscopy ◽  
Principal Component ◽  
Reflectance Spectroscopy ◽  
Soil Samples ◽  
Partial Least Square ◽  
Least Square ◽  
Partial Least Square Regression

The texture of soil i.e. Sand, Silt and Clay are the most important physical properties of soil for agricultural management. In the agricultural practices to increase the productivity of soil, moisture-holding capacity, aeration and to support the agronomic decisions the knowledge of soil texture is an essential task. For this purpose, the present research gives better results and fast acquisition of soil information with the use of Visible and Near Infrared (Vis- NIR) Diffuse Reflectance Spectroscopy. A total of 30 soil samples from two different locations from Aurangabad, Maharashtra, India were collected and analyzed for soil texture. To detect the soil texture the Vis-NIR DRS has shown levels of accurate results compared to the traditional laboratory method with less time, cost and effort. To measure the reflectance of soil the ASD FieldSpec4 Spectroradiometer (350-2500nm) was used. By the observation of captured spectra by using Spectroradiometer it showed that on the basis of different textural classes the soil samples could be spectrally separable. For database collection and pre-processing, we have used RS3 and ViewSpec Pro software respectively. The statistical analysis by using the combination of Principal Component Analysis (PCA) and Partial Least Square Regression method gives accurate results. To determine the texture of soil sample thirteen features were calculated. The main goal of this research was to determine the soil texture by using statistical methods and to test the performance of VNIR-SWIR reflectance spectroscopy by using the ASD FieldSpec4 Spectroradiometer for estimation of the texture of the soil. The results showed that R2 = 0.99 gives maximum accuracy for clay content and R2 = 0.988 for silt content and R2 = 0.989 for sand. The Root Mean Square Values (RMSE) for clay, silt, and sand are 0.02392, 0.02399 and 0.02289 respectively. With the use of reflectance spectroscopy and statistical analysis by using regression models we can determine the soil properties accurately in very less time.

scholarly journals Mapping homogeneous spectral response zones in a soil profile

2018 ◽  
Author(s):  
Edward J. Jones ◽  
Alex B. McBratney
Keyword(s):  
Soil Profile ◽  
Near Infrared ◽  
Diffuse Reflectance Spectroscopy ◽  
Spectral Response ◽  
Principal Component ◽  
External Parameter ◽  
Dry Conditions ◽  
Soil Units ◽  
Moisture Conditions

Abstract. Homogeneous spectral response zones represent relatively uniform regions of soil that may be useful for identifying soil horizons or delineating soil units spatially. External parameter orthogonalisation (EPO) and direct standardisation (DS) were assessed for their ability to conserve intrinsic soil information of spectra under variable moisture conditions, as experienced when taking measurements in situ. A 1 m × 1 m section of a soil profile was intensively sampled using visible near-infrared diffuse reflectance spectroscopy at 2.5 cm vertical intervals and 10 cm horizontal intervals. Further samples were taken on a 10 cm grid and scanned in a laboratory under field moist and air-dry conditions. A principal component space was constructed based on the in situ scans following either EPO transformation, DS transformation or following pre-processing only (PP). Scores from the first four principal components – which accounted for more than 0.97 of the total variance in each case – were subject to k-means clustering to identify homogeneous spectral response zones. Laboratory-based scans were then projected onto the same principal component space and fitted to the pre-existing cluster centroids. Both EPO and DS were found to have potential in reconciling differences observed between in situ and laboratory-based measurements compared to pre-processing only (PP). EPO outperformed DS in terms of conserving the relationship between PC scores (LCCC: EPO = 0.84, DS = 0.58, PPO = 0.44; RMSE: EPO = 11.8, DS = 15.4, PPO = 38.5) and also in identifying homogeneous spectral response zones that corresponded to field observed horizons.

Non-Destructive Assessment of Edible Seed Chemical Content by Near-Infrared Hyperspectral Imaging for the Improvement of Nutritional Traits in Bottle Gourd (Lagenaria Siceraria)

2021 ◽  
Vol 7 (5) ◽  
pp. 75-81
Author(s):  
Nadège Aurelie N’dri-Aya ◽  
◽  
Irié Vroh-Bi ◽  
◽  
Keyword(s):  
Hyperspectral Imaging ◽  
Near Infrared ◽  
Principal Component ◽  
Bottle Gourd ◽  
Lagenaria Siceraria ◽  
Absorption Bands ◽  
Tropical Regions ◽  
Nutrition Security ◽  
Chemical Content ◽  
Non Destructive

The edible seeds of bottle gourd [Lagenaria siceraria (Molina) Standl.] are rich in oils, proteins and minerals of high nutritional quality. They are highly prized in pan tropical regions where they constitute valuable resources for food and nutrition security. In this study, near-infrared hyperspectral imaging (NIR-HSI) was combined with chemometrics to assess the variability of seed chemical content of African cultivars for the selection of nutritional traits. Six hundred seeds of four accessions belonging to two cultivars were collected from the Ivory Coast (West Africa) and analysed. The NIR-HSI spectra collected on whole seeds in the 1100-2400 nm range revealed that the main absorption bands of the seed chemical content were associated with water, lipids and proteins. The absorbance values between seeds of the same accession in these spectral regions varied up to 1.8 folds. Among the two chemometric tools used, principal component analysis (PCA) did not separate the accessions while Partial Least Squares Discriminant Analysis (PLS-DA) discriminated the accessions with 87.33 % to 94.67 %, and the cultivars with 90 % to 92 % correct classification. Seed oils from bottle gourd are for instance rich in linoleic acid which is an essential fatty acid for human health. The non-destructive and qualitative determination of the content of single seeds was demonstrated in the study and provides the opportunity to select superior seeds for the improvement of key nutritional traits in bottle gourd. Lagenaria siceraria, near-infrared hyperspectral imaging, seed chemical content, PCA, PLS-DA, nutrition security

Near-Infrared Spectroscopic Measurements of Structural Changes in Starch-Containing Extruded Products

1996 ◽  
Vol 50 (9) ◽  
pp. 1134-1139 ◽  
Author(s):  
S. Millar ◽  
P. Robert ◽  
M. F. Devaux ◽  
R. C. E. Guy ◽  
P. Maris
Keyword(s):  
Structural Changes ◽  
Near Infrared ◽  
Mechanical Energy ◽  
Principal Component ◽  
Physical Structure ◽  
Extrusion Cooking ◽  
Absorption Bands ◽  
Energy Inputs ◽  
Specific Mechanical Energy ◽  
Extruded Products

Near-infrared spectroscopy was evaluated as a means of following physical and chemical changes in starch during the extrusion cooking of wheat flour under the Measurements and Testing Program of the European Commission. With the use of principal component (PC) and canonical correlation (CC) analyses, samples could be classified according to the severity of the extrusion cooking conditions. An interpretation of the spectra showed that the different processing conditions modified the physical structure of the starch molecules. At low values of specific mechanical energy inputs, starch was partially crystalline and the near-infrared spectra exhibited characteristic absorption bands at about 1428, 1520, and 1587 nm. As the energy inputs increased, causing a change to molten starch, the intensity of the bands at 1520 and 1587 nm decreased, with a shift of the 1428-nm absorption band towards longer wavelengths also being observed. The changes that occurred were thought to be due to a disruption of the intra- and intermolecular hydrogen bonding of the starch. At the higher levels of specific mechanical energy inputs, the starch molecules underwent further structural modification, resulting in their partial degradation.

scholarly journals Near Infrared Hyperspectral Imaging in Transmission Mode: Assessing the Weathering of Thin Wood Samples

2016 ◽  
Vol 24 (6) ◽  
pp. 595-604 ◽  
Author(s):  
Knut Arne Smeland ◽  
Kristian Hovde Liland ◽  
Jakub Sandak ◽  
Anna Sandak ◽  
Lone Ross Gobakken ◽  
...  
Keyword(s):  
Solar Radiation ◽  
Near Infrared ◽  
Prediction Models ◽  
Hyperspectral Image ◽  
Principal Component Regression ◽  
Principal Component ◽  
Transmission Mode ◽  
Infrared Wavelength ◽  
Robust Prediction ◽  
Wooden Surface

Untreated wooden surfaces degrade when exposed to natural weathering. In this study thin wood samples were studied for weather degradation effects utilising a hyperspectral camera in the near infrared wavelength range in transmission mode. Several sets of samples were exposed outdoors for time intervals from 0 days to 21 days, and one set of samples was exposed to ultraviolet (UV) radiation in a laboratory chamber. Spectra of earlywood and latewood were extracted from the hyperspectral image cubes using a principal component analysis-based masking algorithm. The degradation was modelled as a function of UV solar radiation with four regression techniques, partial least squares, principal component regression, Ridge regression and Tikhonov regression. It was found that all the techniques yielded robust prediction models on this dataset. The result from the study is a first step towards a weather dose model determined by temperature and moisture content on the wooden surface in addition to the solar radiation.

Diffuse reflectance spectroscopy of Pu ions in zirconolite and perovskite

2004 ◽  
Vol 824 ◽  
Author(s):  
E. R. Vance ◽  
K. S. Finnie ◽  
Y. Zhang ◽  
B. D. Begg
Keyword(s):  
Electronic Absorption ◽  
Diffuse Reflectance ◽  
Near Infrared ◽  
Diffuse Reflectance Spectroscopy ◽  
Charge Compensation ◽  
Reflectance Spectroscopy ◽  
Visible Range ◽  
Absorption Bands ◽  
Ambient Temperatures ◽  
Polycrystalline Ceramic

AbstractDiffuse reflectance spectroscopy measurements at ambient temperatures have been made over the near infrared-visible range (5000-25000 cm−1) on polycrystalline ceramic zirconolite (CaZrTi2O7) and perovskite (CaTiO3) samples doped with Pu4+. The Pu concentrations were varied between 0.001 and 0.1 formula units. The Pu ions gave rise to a number of unresolved intraconfigurational f-f electronic absorption bands of a few hundred cm−1 bandwidth. Pu ions were targeted to substitute in the Ca sites as either trivalent or tetravalent species and as tetravalent species in the Zr site of zirconolite by the appropriate choice of charge compensation and firing atmosphere. There was approximate agreement of the Kubelka-Munk absorption intensities with Beer's Law for the different Pu4+ substitution schemes, apart from some “new” bands, attributed to impurities, observed in the most dilute zirconolite sample. No clear spectral differences were evident when Pu4+ was targeted to Ca or Zr sites in zirconolite. Samples prepared in reducing atmospheres with a view to producing Pu3+ were strongly absorbing, leading to suppression of Pu transitions.

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