Dimensional Stabilization of Engineered Wood Floor Using Linseed Oil and Paraffin Wax Impregnation

Engineered wood flooring comprises three or more layers of wood veneer adhered together to create a plank. The surfaces were coated to scale back water absorption. However, as wood is a hygroscopic substance, it loses and gains moisture from the atmosphere. This affects the dimensional stability of the floor badly, which emanates wide gaps between boards, cupped edges, crowning edges, and bulking of boards. Hence, the main intention of this study was to stabilize the engineered wood flooring by filling the wood cavity with linseed oil, paraffin wax, and a mixture of both, and evaluate the physical, mechanical property of treated and non-treated engineered wood flooring boards. The treatments were conducted at different temperature and durations. Keywords: Dimensional stabilization, Wood modification, Wood floor, Linseed oil, Paraffin wax, Impregnation

Thermal Conductivity of Poplar Wood Veneer Impregnated with Graphene/Polyvinyl Alcohol

Intending to achieve more green and economical graphene impregnated modified fast-growing poplar wood veneer for heat conduction, this study proposes and investigates the feasibility of modified veneer with graphene/Polyvinyl alcohol (Gr/PVA) impregnation mixture to improve its thermal conductivity. The absorbance and viscosity of the Gr/PVA impregnation mixtures are observed to expound the Gr/PVA ratio effects on the mixtures. Simultaneously, the weight percent gain, chromatic aberration, and thermal conductivity of the modified veneers are measured to determine the impregnation effect and the optimal impregnation formula. Further, the chemical structure, crystallinity, and thermal stability of the optimal sample impregnated with Gr/PVA are tested. The results show that the thermal properties of the Gr/PVA impregnated modified veneer have not all been improved. Still, both the dispersibility of the impregnation mixtures and the impregnation effect is affected by the Gr/PVA ratio. The data shows that the optimal thermal conductivity of modified veneer, which is up to 0.22 W·m−1·K−1 and 2.4 times the untreated one, is dipped by the mixture of 10 wt.% PVA concentration and 2 wt.% MGEIN addition. According to the characterization tests, the crystallinity of the modified veneer reduces, but the thermal stability improves.

The Effect of Bacterial Cellulose on The Thermo Hydro-Mechanical Treatment of Wood Veneer

Wood is the largest source of cellulose in the nature however it has a low strength. In other hand, bacteria cellulose as a pure cellulose has a higher tensile strength than wood. Wood reinforced with bacterial cellulose was produced by self-assembly approach with veneer soak into the fermentation medium. The product of this research is hybrid veneer processed thermos-hydro-mechanical treatment. It has been used to give a change in its mechanical properties. This research analyzed mechanical tensile test, Fourier transform infrared spectroscopy, and field emission scanning electron microscopy. The result showed that bacteria cellulose had impact to increase tensile strength of veneer and improve the molecular strength between cellulose fibers. Hydrogen bonds were formed between veneer fibers and bacterial cellulose then those bonds stick together and resulted in strong adhesion.

Identification of mahogany sliced veneer using handheld near-infrared spectroscopy device and multivariate data analysis

The illegal logging of valuable tree species is mainly motivated by a global market that consumes logs, lumber, veneers, and furniture. The use of objective techniques to identify species and the effects of international initiatives such as CITES rules contributes to controlling trade, exploitation, and smuggling of these products. The anatomical identification of wood veneers is limited due to the loss of several anatomical characters in the production process of the veneers. For this reason, we propose the Near-Infrared Spectroscopy technique associated with chemometric tools for the discrimination of wood veneer of woods with similar general characters: Swietenia macrophylla King (mahogany), Carapa guianensis Aubl. (andiroba), Cedrela odorata L. (cedro), Micropholis venulosa Pierre (curupixá), and Hymenaea coubaril L. (jatobá) using a portable spectrometer.The development of the discrimination models was performed using the PLS-DA (Partial Least Squares for Discriminant Analysis) algorithm. The detection and subsequent exclusion of outliers were performed based on Hotelling T2, Q residuals, and errors in estimating class values. The PLS-DA models showed an efficiency between 96.5% and 100% in the samples’ discrimination among the five forest species. In conclusion, the portable NIRS technology and the PLS-DA models were suitable for the rapid identification and discrimination of the wood veneers.

An Empire of Letters: The Vindolanda Tablets, Epistolarity, and Roman Governance

Around 800 Roman tilia—writing tablets made from folded slivers of wood veneer and a little over postcard size—have been found in archaeological investigations at Vindolanda, a Roman fort in northern England. Dated to the period 85 CE to 130 CE, their existence is helping revise knowledge of the Roman letter and the part it played in how military governance was organized, the ways in which personal, public, and military aspects were interrelated, as well as informing other relationships existing between the occupying imperial legions and local Britons. Discussion focuses on four connected areas of inquiry. Firstly, it explores the relationship of the several hundred letters to the many other kinds of Vindolanda writings, for this gives perspective on the boundaries of these different genres and the uses to which they were put. Secondly, it analyzes the many overlaps that exist between what are one-to-one letters and what are public documents, and it considers the significance of this for understanding the legion as a form of familia. Thirdly, it discusses the role that letters and their cognates, and writing and records generally, played in Roman military occupation and rule. The Vindolanda letters had a particular import because their characteristic mode of expression facilitated and enhanced connections between members of the auxiliary cohorts, in ensuring that the performance of military duties occurred in the context of familia-like bonds, and for this to permeate beyond the letters, to the life-and-death activities of soldiering involved. And fourthly, it discusses the importance for epistolary studies of these matters.