Tree Rings And Climate

Principles of Isotope Geology

The analysis of chemical structural characteristics of biorefinery product streams (such as lignin and tannin) has advanced substantially over the past decade, with traditional wet-chemical techniques being replaced or supplemented by NMR methodologies. Quantitative 31P NMR spectroscopy is a promising technique for the analysis of hydroxyl groups because of its unique characterization capability and broad potential applicability across the biorefinery research community. This protocol describes procedures for (i) the preparation/solubilization of lignin and tannin, (ii) the phosphitylation of their hydroxyl groups, (iii) NMR acquisition details, and (iv) the ensuing data analyses and means to precisely calculate the content of the different types of hydroxyl groups. Compared with traditional wet-chemical techniques, the technique of quantitative 31P NMR spectroscopy offers unique advantages in measuring hydroxyl groups in a single spectrum with high signal resolution. The method provides complete quantitative information about the hydroxyl groups with small amounts of sample (~30 mg) within a relatively short experimental time (~30–120 min). This protocol describes a quantitative 31P NMR spectroscopy approach for the analysis and determination of hydroxyl groups on biorefinery resources such as lignins and tannins.

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Determination of hydroxyl groups in biorefinery resources via quantitative 31P NMR spectroscopy

Wood is gaining increasing attention in applications related to solar steam generation because of its porous structure with microchannels, low heat conduction properties, highly hydrophilic properties and renewability. Wood surface modification is required to improve steam generation performance because of its low optical absorptivity. Unfortunately, the high energy consumption fabrication process and high cost of current photothermal conversion coatings on wood impede its large-scale application. This study develops a facile pyrrole polymerization method to acquire polypyrrole decorated wood (PPy–wood) for solar evaporation enhancement. The black PPy decoration considerably improves the wood light absorption, resulting in a high absorbance (>90%) of PPy–wood within a broad wavelength range, from the ultraviolet region to the near infrared region (300–2500 nm). The combination of advantages related to wood (microchanneled porous structure, high hydrophilicity and thermal insulation) and PPy (broadband and high solar absorption capacity) for easy and fast steam generation makes PPy–wood an ideal solar steam generator, which shows rapid evaporation abilities (1.014 kg m−2 h−1) and high evaporation efficiency (72.5%) under simulated one sun irradiation. Moreover, the obtained clean water using PPy–wood as the steam generator shows low ion concentrations and high transmittance, demonstrating that PPy–wood possesses excellent potential for seawater desalination and sewage treatment. Thus, such PPy–wood is a potential candidate for water desalination and purification to address water scarcity issues through the effective utilization of clean energy.

A wood–polypyrrole composite as a photothermal conversion device for solar evaporation enhancement

Wood Chemistry, Fundamentals and Applications, Second Edition, examines the basic principles of wood chemistry and its potential applications to pulping and papermaking, wood and wood waste utilization, pulping by-products for production of chemicals and energy, and biomass conversion.

Wood chemistry: fundamentals and applications.

FTIR and Py-GC-MS data of wood from various living oak species and Iberian shipwrecks.

Variation of wood color and chemical composition in the stem cross-section of oak (Quercus spp.) trees, with special attention to the sapwood-heartwood transition zone.

Wood is a lignocellulosic and biodegradable material widely used for diverse applications. The complex nature of wood is due to its structure and chemical composition, which are closely related to tree taxonomy and to environmental factors of growing locations. Studies on wood chemical composition are of interest and permit to gain deeper understanding. In this light, the aim of this thesis was to develop tools for identification of species and provenance based on organic chemical parameters of wood used for shipbuilding in the Iberian Peninsula (15th to 17th century). The methodology developed in this thesis, concerned the combination of multivariate data analysis methods, together with wood chemical characterisation techniques (FTIR and Py-GC-MS).

Potential biomarkers of provenance of the wood from iberian typology shipwrecks (15th to 17th centuries)

Infestation by a moth woodborer species is causing mortality of Sonneratia alba Sm. mangrove by tunneling through the inner bark, cambium and conductive tissue. Infestation leads to death of some infested branches, whereas in other cases infested branches have been observed to recover from infestation. We have used Fourier transform infrared spectroscopy (FTIR) to investigate the differences in macromolecule (polysaccharide and lignin) content present in branches that died (D) of the infestation, those that recovered (R) from the infestation and control branches (C) that were not subject to any infestation. Wood samples were taken from four sampling plots (A, B, C and D) in Gazi Bay (Kenya). From each of the four plots, 15 S. alba branches were taken from five trees, from which 1 cm thick discs were cut from each of these branches to be used as samples. To identify the most characteristic FTIR bands for the three groups of samples, Principal Component Analysis (PCA) was applied on the transposed data matrix. Furthermore, canonical discriminant analysis was applied on the data considering the main FTIR band that would be identified through the PCA factors. Finally, One-way ANOVA and post hoc test were used to verify the significance of the observed trends. Branches that recovered from infestation had higher relative abundance of lignified cells. We conclude that insect-infested S. alba undergo changes related to the lignocellulosic contents. The infestation induces a decrease of the proportion of the polysaccharide content and an increase of the proportion of the lignin contents.

Biochemical response of Sonneratia alba Sm. branches infested by a wood boring moth (Gazi Bay, Kenya).

Clubfoot malformation is the most common serious congenital anomaly af-fecting the foot in children. Its treatment by the Ponseti method is simple, prof-itable and widely used in the world. Objective: The objective of this study was to identify the factors of the failure of its treatment by the Ponseti method. Material and Method: We carried out a retrospective and descriptive study of cases of congenital equinus clubfoot varus at the Reference Health Care Center of Commune III of Bamako over 26 months from September 2020 to November 2022. Data were treated with the utmost anonymity. Result: This study was performed on 44 children seen for clubfoot: male (68%) and female (32%), with a sex ratio of 2.1. We obtained 13 cases of recidivism includ-ing 7 boys and 6 girls. We found 21 cases of unilateral and 23 bilateral; among which 9 recurrences were found against 4 in the unilateral forms. 85% of recurrences did not have good adherence to the splint and 62% did not come regularly for follow-up consultation. We obtained 33 children

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The Factors of the Failure in the Treatment of Congenital Equinus Clubfoot Varus by the Ponseti Method at the Reference Health Care Center (CSREF) of Commune III of Bamako

Mohamed Traoré

Papers

FTIR and Py-GC-MS data of wood from various living oak species and Iberian shipwrecks.

Variation of wood color and chemical composition in the stem cross-section of oak (Quercus spp.) trees, with special attention to the sapwood-heartwood transition zone.

Potential biomarkers of provenance of the wood from iberian typology shipwrecks (15th to 17th centuries)

Biochemical response of Sonneratia alba Sm. branches infested by a wood boring moth (Gazi Bay, Kenya).

The Factors of the Failure in the Treatment of Congenital Equinus Clubfoot Varus by the Ponseti Method at the Reference Health Care Center (CSREF) of Commune III of Bamako