Estimation of the mechanical properties of wood from Eucalyptus urophylla using near infrared spectroscopy

Mechanical properties studies of wood usually involve destructive wood assessments, with time-consuming tests that use large amounts of resource (wood). Although this is not a limiting factor, it could be attenuated by the use of a nondestructive technique known as near infrared spectroscopy (NIRS). This technique has been applied to evaluate compounds containing C-H, N-H, S-H or O-H bonds, and involves quick analyses and can be applied to process control tasks. The objective of this work is to use the NIRS technique to obtain calibrations for mechanical properties of Eucalyptus sp. wood. A natural E. urophylla hybrid at age 7 was used as obtained from V&M Florestal crops. Spectra were measured directly in solid wood (radial, tangential and transverse faces) and in ground wood, in diffuse reflectance mode, using a Bruker spectrometer in the 800 to 1,500 nm range. The NIRS technique proved suitable to estimate modulus of elasticity in solid wood, with values r=0.91 and RPD=2.6, and in ground wood, with values r=0.87 and RPD=2.0. Modulus of rupture and compressive strength presented r values below 0.9. First and second derivative pretreatments provided a slight increase in correlation values for the properties in question. Calibrations for different plank faces did not present a defined variation pattern. Solid wood and ground wood presented similar correlation values for all properties.

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Near infrared spectroscopy for assessing mechanical properties of Castanea sativa wood samples

Journal of Agricultural Engineering ◽

10.4081/jae.2019.953 ◽

2019 ◽

Vol 50 (4) ◽

pp. 191-197 ◽

Cited By ~ 1

Author(s):

Manuela Mancini ◽

Elena Leoni ◽

Michela Nocetti ◽

Carlo Urbinati ◽

Daniele Duca ◽

...

Keyword(s):

Mechanical Properties ◽

Infrared Spectroscopy ◽

Near Infrared Spectroscopy ◽

Near Infrared ◽

Bending Strength ◽

Prediction Models ◽

Castanea Sativa ◽

Modulus Of Rupture ◽

Current Standard ◽

Standard Samples

Near infrared spectroscopy (NIR) is a technique widely used for the prediction of different chemical-physical features of wood. In this study, the technique was used to assess its potential to predict the mechanical characteristics of wood. Castanea sativa samples of three different European provenances were collected and laboratory tests were performed to assess the mechanical properties of wood samples. Modulus of elasticity (MOE), load-deflection curve and modulus of rupture (MOR) were calculated by using INSTRON machine with three points bending strength with elastic modulus, while density (D) was calculated according to the current standard. Samples were then analysed by means of NIR spectroscopy. The raw spectra were pre-processed and regression models were developed. Variables selection techniques were used to improve the model performance. In detail, MOE regression model returned an error of 696.01 MPa (R2=0.78). Instead, MOR and D prediction models must be further investigated on a wider number of samples considering the high variability in physical characteristics of chestnut wood. The results demonstrated the possibility to use NIR technique for the prediction of the mechanical properties of wood providing useful indications in evaluation-screening processes. Indeed, the presence of the principal wood compounds (cellulose, hemicellulose and lignin) and their influence in the characterisation of mechanical stress reactions were confirmed.

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Use of near infrared spectroscopy to measure the chemical and mechanical properties of solid wood

Wood Science and Technology ◽

10.1007/s00226-003-0213-5 ◽

2004 ◽

Vol 38 (4) ◽

Cited By ~ 114

Author(s):

StephenS. Kelley ◽

TimothyG. Rials ◽

Rebecca Snell ◽

LeslieH. Groom ◽

Amie Sluiter

Keyword(s):

Mechanical Properties ◽

Infrared Spectroscopy ◽

Near Infrared Spectroscopy ◽

Near Infrared ◽

Solid Wood

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The Main Mechanical Properties of New Chinese Fir Clones and Their Rapid Prediction by Near-infrared Spectroscopy

Canadian Journal of Forest Research ◽

10.1139/cjfr-2021-0048 ◽

2021 ◽

Author(s):

Ru Jia ◽

Yurong Wang ◽

Rui Wang ◽

Haiyan Sun ◽

Shengquan Liu ◽

...

Keyword(s):

Mechanical Properties ◽

Infrared Spectroscopy ◽

Near Infrared Spectroscopy ◽

Near Infrared ◽

Prediction Models ◽

Wood Properties ◽

Chinese Fir ◽

Modulus Of Rupture ◽

Tangential Section ◽

Smoothing Methods

Due to rapidity and accuracy, near-infrared spectroscopy (NIRs) is powerful tool to establish appropriate prediction models with an innovative method for the evaluation of wood properties. In order to reveal mechanical qualities of clonal Chinese fir woods and determine sound prediction models of mechanical properties, four main mechanical properties of six Chinese fir clones (Yang 020, Yang 061, Kaihua 3, Kaihua 13, Daba 8, Kailin 24) were evaluated by NIRs. As a result, Kaihua 13, Kailin 24 and Yang 020 showed good mechanical properties. To estimate mechanical properties with NIRs, different methods should be adopted for different properties. The average spectra of radial section and tangential section combined with multiple scattering correction (MSC) and Savitzky-Golay (S-G) smoothing methods were used to predict the modulus of rupture (MOR) and modulus of elasticity (MOE). By adopting spectra of cross section and taking MSC and S-G smoothing methods for pretreatment, the models of compressive strength parallel to grain could deliver the best results. For wood hardness, the models established with average spectra of three sections and first derivative method were preferred. The correlation coefficients of the prediction models were between 0.84 and 0.90, and those of calibration models were between 0.75 and 0.96.

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Quantifying contact force artefact in near infrared spectroscopy

10.24124/2021/59135 ◽

2021 ◽

Author(s):

◽

Timothy Schwab

Keyword(s):

Experimental Investigation ◽

Adipose Tissue ◽

Infrared Spectroscopy ◽

Contact Force ◽

Near Infrared Spectroscopy ◽

Muscle Activation ◽

Diffuse Reflectance ◽

Near Infrared ◽

Photon Propagation ◽

Superficial Tissues

Transcutaneous near infrared spectroscopy (NIRS) of muscle requires coupling between the device and the skin. An unfortunate by-product of this coupling is contact force artefact, where the amount of contact force between the device and the skin affects measurements. Contact force artefact is well known, but largely ignored in most NIRS research. We performed preliminary investigations of contact force artefact to quantify tissue behaviour to inform future NIRS designs. Specifically, we conducted three studies on contact force artefact: (i) an experimental investigation of static load at varied levels of contact force and muscle activation, (ii) an experimental investigation of oscillating load at varied levels of contact force and frequency, and (iii) a Monte Carlo simulation of photon propagation through skin, adipose tissue, and muscle. Our results confirmed that contact force artefact is a confounding factor in NIRS muscle measurements because contact force affects measured hemoglobin concentrations in a manner consistent with muscle contractions. Further, the effects of contact force are not altered by muscle contraction and a likely candidate for the mechanism responsible for contact force artefact is the viscoelastic compression of superficial tissues (skin and adipose) during loading. Simulation data suggests that adipose tissue plays a key role in diffuse reflectance of photons, so any compression of the superficial tissues will affect the reflected signal. Further research is required to fully understand the mechanisms behind contact force artefact, which will, in turn, inform future NIRS device designs.

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Interpreting Diffuse Reflectance and Transmittance: A Theoretical Introduction to Absorption Spectroscopy of Scattering Materials

10.1255/978-1-901019-05-6 ◽

2007 ◽

Author(s):

Donald Dahm ◽

Kevin Dahm

Keyword(s):

Infrared Spectroscopy ◽

Absorption Spectroscopy ◽

Near Infrared Spectroscopy ◽

Mathematical Description ◽

Diffuse Reflectance ◽

Near Infrared ◽

Diffuse Reflection ◽

Theoretical Understanding ◽

Famous Book ◽

Father And Son

A jar of sweets may not appear to be a serious introduction to the attempt to progress the understanding of the challenging nature of what is usually termed "diffuse reflection". However, this book by the father and son team of Don and Kevin Dahm is the first such attempt since the famous book by Wendlandt and Hecht some forty year ago. The sweets are not only useful models, they also indicate the desire of the authors to make this a readable and entertaining book as well as a very serious attempt to advance our theoretical understanding of this complex and confusing topic. The Dahms have been developing and advancing a new theory for the last few years. This book brings it together. It explains the nature of reflected radiation and then the problem of finding a mathematical description of it. In their quest, they have rediscovered and used mathematics that was invented by Sir George Strokes in the 1860s! Much of the current use of near infrared spectroscopy utilizes diffuse reflection or transmission. According to Karl Norris "The development of NIR analysis is being restricted by our lack of a theoretical understanding of diffuse reflection" and he should know!

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