Global nirs models to predict main chemical compounds of Eucalyptus woods

The Nirs technology is particularly well-suited to tree improvement programmes where huge numbers of samples must be analysed, but it can be used in any forestry application where the rapid measurement of wood property data is required or to screen unknown samples. Forest breeders include chemicals wood properties as selection criteria for new varieties, especially lignin, cellulose, hemicellulose. Efforts to develop multi-site, multiple-species, multiple age calibrations are rare. Because of the genotype x environment/ age interactions, we try to develop a very useful multispecies Nirs calibrations to predict chemical properties for varied eucalyptus in term of species, age, and site plantation. Global near infrared models to predict wood properties of Eucalyptus were developed using more than one hundred samples well representatives from 3,000 wood samples. These calibration set was selected on spectral data based on Mahalanobis distance. Samples were provided from different country and location (Congo, Senegal, Brazil), including different species and hybrids of Eucalyptus (E. urophylla, E. grandis, E. camaldulensis, E. urophylla x E. grandis, E. urophylla x E. pellita) from different age (from 5 to 30 years old). The global models tested by cross-validation, based on our own reference data, shown encouraged fits for extractives, lignin, cellulose, hemicelluloses. The models for lignin and extractives showed higher fits than cellulose and hemicellulose even if for these late, the model remained sufficient for prediction. The high variability of chemical properties due to the sampling, associated to the good repeatability of reference measurements, provided high values of model parameters. These results suggest that global calibration could be useful in tree breeding program and for different experiment trials from the fields, to rank genotypes for extractives, lignin, cellose, and hemicelluloses. Local models are more accurate usually and in order to get local models, we are improving our sampling in term of number and origin of wood. The main interest of this type of calibration is the possibility to screen samples for different species, different origins and the other interest is to select new samples to be included in calibration and validation sets. (Résumé d'auteur

Tree crown architecture: a tool for decay resistance evaluation

The variability of natural durability contributes to the bad perception of some wood end-users. In our search, we need to adjust our methods and strategies to estimate natural durability and extract higher value from wood resources. Architectural analysis is essentially a detailed, multilevel, comprehensive and dynamic approach to plant development. Numerous biological process which impact some wood properties like durability are linked with tree development. A better understanding of the interelationship between tree physiology through tree achitecture analysis and natural durability could be an approach to predict this property. This study explore the relation between the crown architecture, decay resistance and wood extractives in Dicorynia guianensis in order to propose tree crown architecture as an evalution decay resistance tool. (Résumé d'auteur

Ultrastructural characterization (morphological and topochemical) of wood pulp fibres

Different electron microscopy techniques including SEM (scanning electron microscopy), FE-SEM (field emission-scanning electron microscopy), TEM (transmission electron microscopy) and Immuno-gold TEM (immuno-gold transmission electron microscopy) were applied in order to gain a better understanding of the influence of the native softwood fibre cell wall ultrastructure including morphology and topochemistry (i.e. lignin and glucomannan distribution) during mechanical pulping. In thermomechanical pulp (TMP) processing, wood fibres undergo structural changes (cell wall delamination and fibrillation) that are regulated by the native fibre micro- and ultrastructure. In addition, novel information was obtained on the fibre cell wall architecture. In contrast, the stoneground wood (SGW) process inflicted severe damage to the fibre structure resulting in transverse and longitudinal fibre breakage. However, juvenile wood SGW fibres showed improved properties (strength and light scattering) compared to mature wood. Ultrastructural aspects of fibre processing and development explained the differences in physical properties observed. During the SGW process, the native morphological fibre cell wall ultrastructure and microfibrillar organization governed the manner of juvenile wood fibre development similar to TMP fibres. Ultrastructural studies on Norway spruce and Scots pine TMPs revealed fundamental features that governed the different behaviour exhibited by the two wood species. Specific ultrastructural characteristics of pine TMP fibre cell walls were explored in relation to both morphology and topochemistry and that regulating the different pine fibre development mechanisms compared to spruce. The negative behaviour shown by Scots pine during TMP processing was most likely attributable to the observed fibre development mechanism. Histochemical techniques were applied to study wood resin associated problems during mechanical and kraft pulping. Studies provided information on the spatial micro-morphological distribution/redistribution of lipophilic extractives that were visualized on single fibre and cell wall fractions. Results from histochemical staining and chemical analysis performed on Norway spruce and Scots pine TMPs showed that there were morphological and chemical differences in the redistribution of extractives between the two species. This may further contribute to the effects of extractives on pulp- and paper properties and processing. Localization of lipophilic birch wood extractives involved in pitch problems was performed using histochemical techniques. Correlated information from gas chromatography-mass spectrometry and specific staining methods gave details on how extractives are removed during processing as well as information on the mechanisms of removal

A Comparison of Unbleached Pulps from Cherry Heartwood and Sapwood

The purpose of the project was to evaluate pulps made from cherry heartwood and sapwood. The amount of heartwood a tree has is an individual trait of the tree rather than a function of geography or environment. Tree breeders can, through selection, reduce or increase the amount of heartwood if it is economically justifiable. Three cherry logs with 50-50 heartwood to sapwood ratio were barked and chipped at S.D. Warren Company in Muskegon. The chips were separated, heartwood from sapwood, by the color difference. The chips were cooked using 20% active alkali, 6 to 1 liquor ratio, for 1.5 hours at 175◦C using an oil bath digester. The oil bath digester had six cartridges of which three were charged with heartwood and three with sapwood. The average yield for heartwood was 44.8% and the average yield for sapwood was 52.7%. The difference in yield was the most significant difference between heartwood and sapwood. The brightness of the sapwood was about 5% greater than heartwood. The Kappa number of the heartwood was 20.8 compared to 22.0 for sapwood. The mullen of heartwood was greater than the sapwood in the freeness range of 100 to 500 C.S.F. by 12 to 16%. The tensile of heartwood was greater than the sapwood in the freeness range of 150 to 500 C.S.F. by 4 to 8%. The tear of sapwood was greater than heartwood in the freeness range of 100 to 500 C.S.F. by 14 to 18%. You cannot totally eliminate either heartwood or sapwood and the resulting trade-off of advantages of increasing or decreasing the percent of heartwood would likely result in only a couple percent advantages in a few parameters. Therefore, the conclusion of this paper is to leave the ratio of heartwood to sapwood to nature

Shared Value in Emerging Markets: How Multinational Corporations Are Redefining Business Strategies to Reach Poor or Vulnerable Populations

This report illuminates the enormous opportunities in emerging markets for companies to drive competitive advantage and sustainable impact at scale. It identifies how over 30 companies across multiple sectors and geographies design and measure business strategies that also improve the lives of underserved individuals

Rapid estimation of gamma number of viscose by UV Spectrophotometry

Viscose process is the most important method for industrial cellulose dissolution. The degree of substitution (DS) is an important parameter in cellulose derivatives, and it is usually expressed as a gamma number (γ No.). In this work, viscose was prepared from eucalyptus and cotton linter dissolving pulps. Two methods were used for by-product separation: coagulation method (CM, reference) and ion exchange method (IEM). Similar γ Nos. were obtained with both methods for viscoses from cotton linters. The molar absorptivity of cellulose xanthate at 303 nm (e303nm) was determined by, firstly, measuring the absorbance of different purified viscoses and, subsequently, drawing a linear regression with the values obtained. The purification efficacy of IEM was analyzed from the UV peaks obtained in the range of 220-380 nm of the original and purified viscoses. The disappearance of the absorption of the main byproduct, sodium trithiocarbonate, was observed. Finally, with the e303nm mentioned above and the absorbance measurement of the purified viscoses, their γ Nos. were determined using a spectrophotometric method (SM). This would indicate that UV spectrophotometry could be used to estimate this parameter in a quick and easy way, which is decisive for the use of viscose in regenerated cellulose products.Fil: Lanieri, Diana Beatriz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; ArgentinaFil: Olmos, Graciela Viviana. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología Celulósica; ArgentinaFil: Alberini, Ivana Cecilia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología Celulósica; ArgentinaFil: Maximino, Mirta Graciela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe; Argentina. Universidad Nacional del Litoral. Facultad de Ingeniería Química. Instituto de Tecnología Celulósica; Argentin

Nirs tools for prediction of main extractives compounds of teak (Tectona grandis L.) heartwood

Biochemical and physiological process which occurred during heartwood formation have consequences on wood properties such as colour, natural durability and some mechanical properties. However, it is very time-consuming to take measurements of extractives contents. Teak has been reported to contain 1-hydroxy- 2-methyl-anthraquinone, 2-hydroxy-methyl-anthraquinone, 2-methyl- anthraquinone, lapachol, 1,4-naphthoquinone for the main compounds. In teak, natural durability is ascribed to extractives. Consequently, it's possible to estimate natural durability by measurement of extractives indirectly. For the purposes of selection for the production of improved varieties, the number of samples to be measured rapidly exceeds the capacity of a traditional laboratory. Near-infrared spectroscopy approach, based on spectral data and reference data, is a tool enabling many of the chemical properties of wood to be predicted and the number of laboratory measurements to be reduced exponentially. The issue here is a question of checking the effectiveness of NIRS tool to build models and predict the main extractive compounds of teak wood from Ivory Coast. We try to calibrate these chemical properties with Nirs spectral information measured on grounded wood. The results show the possible use of NIRS to predict total phenol content and some main extractive compounds of teak heartwood as tectoquinone, 2-hydroxymethylanthraquinone,Consequently, after verification on other sets of teak samples, which may or may not be included in the prediction model, NIRS can be used to predict extractive compounds accurately for a large number of samples, making it possible to estimate natural durability indirectly and to include these characteristics in the selection criteria for classifying wood and high throughput phenotyping. (Résumé d'auteur

Switchgrass storage effects on the recovery of carbohydrates after liquid hot water pretreatment and enzymatic hydrolysis

Perennial grasses that would be used for bioenergy and bioproducts production will need to be stored for various periods of time to ensure a continual feedstock supply to a bioprocessing facility. The effects of storage practices on grass composition and the response of grasses to subsequent bioprocesses such as pretreatment and enzymatic hydrolysis needs to be understood to develop the most efficient storage protocols. This study examined the effect of outdoor storage of round switchgrass bales on composition before and after liquid hot water pretreatment (LHW) and enzymatic hydrolysis. This study also examined the effect of washing LHW pretreated biomass prior to enzymatic hydrolysis. It was determined that switchgrass composition after baling was stable. As expected, glucan and lignin contents increased after LHW due to decreases in xylan and galactan. Washing biomass prior to enzymatic hydrolysis reduced saccharification, especially in samples from the interior of the bale, by at least 5%

Potential valorization of wood extractives from waste products of steam distillation of Aniba rosaeodora: antitermitic activity

Aniba rosaeodora, is a slow growing evergreens of the Lauraceae family which are indigenous over a wide range of the Greater Amazon Region (the Guianas and Venezuela, Brazilian Amazon¿). The essential oil obtained from the wood has a characteristic aroma and is a long-established ingredient in the more expensive perfumes. The wood is also composed with alkaloid compounds like anibin. These compounds contribute to the protection of the wood against insects and fungi. This work is focused on the valorization of steam distillated sawdust; the sawdust was extracted with methanol in order to study the antitermitic activity of the extract. The methanolic extract shows an efficacy against termites at low concentrations according to the EN 117 standard. (Résumé d'auteur

First report on the termiticidal activity of extracts of Annona squamosa (Annonaceae) seeds and on its active constituent squamocins

Termites inflict severe damage on wood and impede usage of several forest species. The biological metabolites could potentially replace synthetic termiticidal products which are becoming more restricted to use. Annona squamosa is well known for its edible fruits - tropical custard apple. Annonaceous tetrahydrofuran acetogenins have attracted much interest due to their broad range of biological activities, and seeds containing them are reported to show insecticidal and abortifacient properties. Under the course our exploratory investigation of non food valuable products from less known forest species (here from Benin), the fractions obtained from defatted cake of Annona squamosa seeds with solvents covering a broad range of polarity, revealed a significant termiticidal activity, when applied at 5 - 10 mg/cm² (non-polar solvent) and 1.2 - 5 mg/cm² (case of a more polar solvent). Based on the result (0: no attack) from the standard procedure EN 118, these extracts could be used for preserving wood under class of use number 1. A derivatization step with Kedde reagents A and B, elemental analysis C,H,O, HPLC/MS and proton NMR showed the presence of squamocin type acetogenins (MW 594 and 622 g/mole: C35H62O7 and C37H66O7) as main components of the most active fraction (100% mortality within 7 days for a sample applied at 2 mg/cm²). Additional work will be undertaken to confirm the structure of most active compounds in the extracts, and to check whether some Annona squamosa seed extracts (non timber products of sustainable management of native forest) could show even higher activity to protect wood under more adverse conditions and be alternative active natural products to synthetic compounds. (Résumé d'auteur