Timber Wood Research Articles

Environmental Isolation of Sporothrix brasiliensis in an Area With Recurrent Feline Sporotrichosis Cases.

Sporotrichosis has been expanding throughout the Brazilian territory in recent years. New outbreaks have emerged, and consequently, the sporotrichosis agents, mainly Sporothrix brasiliensis, should remain in the environment somehow. Therefore, the aim of this study was to investigate the presence of Sporothrix spp. in the environment from an area of ​​the Rio de Janeiro state, Brazil, with recurrent cases of human and animal sporotrichosis. Abandoned demolition timber wood samples were collected in the garden of a house where the cases of human and feline sporotrichosis have occurred in the last 10 years. The environmental survey revealed a Sporothrix spp. colony from the serial dilution cultures of one abandoned demolition wood sample. In addition, a fungal strain isolated from a cat with skin lesions that lived in the house was also included in the study. The species-specific PCR, and calmodulin partial sequencing identified the environmental and cat isolates as S. brasiliensis. Furthermore, the phylogenetic analysis performed with the partial sequences of internal transcribed spacer region and constitutive genes (calmodulin, β-tubulin, and chitin synthase) showed high similarity between environmental and cat isolates from the same geographic region. Moreover, the antifungal susceptibility test revealed that the minimal inhibitory concentration of itraconazole from the environment isolate was lower than the cat isolate, while amphotericin B and terbinafine were similar. Our results show that S. brasiliensis is able to maintain itself in the environmental material for years. With this, we corroborate that the eco-epidemiology of sporotrichosis is not well understood, and despite the major occurrence of S. brasiliensis in Brazil, it is rarely isolated from the environment.

Performance Analysis of Full Assembly Glass Fiber-Reinforced Polymer Composite Cross-Arm in Transmission Tower.

The usage of glass fiber reinforced polymer (GFRP) composite cross-arms in transmission towers is relatively new compared to wood timber cross-arms. In this case, many research works conducted experiments on composite cross-arms, either in coupon or full-scale size. However, none performed finite element (FE) analyses on full-scale composite cross-arms under actual working load and broken wire conditions. Thus, this work evaluates the performance of glass fiber reinforced polymer (GFRP) composite cross-arm tubes in 275 kV transmission towers using FE analysis. In this study, the performance analysis was run mimicking actual normal and broken wire conditions with five and three times more than working loads (WL). The full-scale assembly load test experiment outcomes were used to validate the FE analysis. Furthermore, the mechanical properties values of the GFRP composite were incorporated in simulation analysis based on the previous experimental work on coupons samples of GFRP tubes. Additionally, parametric studies were performed to determine the ultimate applied load and factor of safety for both normal and broken wire loading conditions. This research discovered that the GFRP composite cross-arm could withstand the applied load of five times and three times working load (WL) for normal and broken wire conditions, respectively. In addition, the factor of safety of tubes was 1.08 and 1.1 for normal and broken wire conditions, respectively, which can be considered safe to use. Hence, the composite cross-arms can sustain load two times more than the design requirement, which is two times the working load for normal conditions. In future studies, it is recommended to analyze the fatigue properties of the composite due to wind loading, which may induce failure in long-term service.

The deterioration of the Pueblo Bonito Great House in the Chaco Culture National Historical Park, New Mexico, USA.

Pueblo Bonito is the iconic pre- Columbian structure in Chaco Culture National Historical Park, a World Heritage Site in northwestern New Mexico, USA. The structure, dating to about 850–1150 Current Era, and built of quarried sandstones, wooden timbers and a mud mortar, has been the subject of archaeological investigations for over a century. The present study is based on the examination of historical photographs of Pueblo Bonito dating from 1887 to the 1920s. It is a retrospective assessment to determine if structural damages, depicted on the photographs, could be attributed to identifiable agents that might have been present at the time of Pueblo Bonito occupancy. A likely causal agent of deterioration at Pueblo Bonito was the inability of Ancestral Puebloan engineers to manage the impacts from the annual precipitation, presently measured at about 220 mm. A resulting time-dependent event was rot to wetted roof and ceiling timbers, lintels, and wall support beams which required decades of incubation by wood decay fungi to reduce wood tensile strength to levels leading to roof and wall collapse. Important time- independent events that could occur any time after construction include water action on the mud mortar which resulted in unstable gravity load paths in stone walls, ponding of water in walls which when frozen would lead to the blowout of wall segments, and the occasional flood that disrupted foundations. Pueblo Bonito may have been an occupation site for centuries but the lifetime of individually constructed rooms may have only been decades, resulting in several build- repair- or abandon cycles being part of the history of that Great House.

WOOD MASTER ALİ ÖNDER FROM GÜRÜN AND HIS WORKS

Wood art is one of the arts products, starting from the early periods of Turkish-Islamic art. The origin of wood is the Arabic hasebin (wood, timber) and its plural wood. It means wood material and timber used for production purposes. The beginning of the use of wood with its durability and texture, needs of people, has led to the emergence of woodworking in architecture, art history and handicrafts. It has changed and developed in the historical process. The samples found in the kurgans in the Altai show that the Central Asian Turks were interested in wood. The first examples of Islamic architecture in Syria, the wooden works of the Umayyad’s and later the Abbasids bear the traces of woodwork of the period. The Seljuk’s were also interested in wood, and the Ottomans brought woodworking to the highest level. They created works such as pulpit, mihrap, lectern, Qur'an case, drawer and coffin from wood used in architecture as building materials. Mihrab is a word derived from the root of harp, meanings the Arabic palace, the harem, the sultan's throne is located place, the statue cell of the Christian saints, the arbor, the pavilion, the high place, the head of the assembly. In the historical course, it became the name of the place where the imam stood in mosques. The pulpit, the stepped architectural element in mosques to be seen better and to be heard better while giving a sermon, is the word is derived from the root nebr meaning raising. It’s the place you go up gradually. Kürsü is Kürsi in Arabic means a chair that is placed on top of each other or formed from various parts and sat on. In Anatolia, the art of wood maintains its importance with cultural interaction and changes until today. With the use of technological innovations, today the number of masters who produce handicrafts has decreased considerably. In this study, information has been given about Ali Önder, one of the masters who set his heart on this work, and the construction stages of the pulpit, lectern and mihrap he prepared, and about the wooden art. Önder was born in 1933 in the Gürün district of Sivas. He started to learn woodworking from his father at the age of seven, and has been continuing his professional life, for 35-40 years by making mihrab, pulpits and lecterns. Önder does not charge for the works he prepared for mosques, was awarded the International Goodness Award given to seven people from different parts of the world by the Turkish Religious Foundation.

Fungi species causing dieback and wilt diseases in shisham [Dalbergia sissoo (Roxb)] and impact of various fungicides on their management

ObjectivesDalbergia sissoo commonly known as ‘shisham’ is a multipurpose tree commonly used to produce high-quality timber wood. However, it is under extinction threat due to several biotic and abiotic factors. The fungi species causing dieback and wilt diseases are poorly studied and efficacy of different fungicides for their management has been rarely tested. Therefore, infected root and shoot samples of shisham trees were collected from different localities in Bahawalpur through this study. MethodsSamples were analyzed for pathological observations which revealed that Fusarium, Alternaria, Curvularia, Dreshcelera, Phoma, Aspergillus, Paecilomyces, Haphlographium, Steganosporium, Ostracoderma, Cephalospora, Penicillium, and Briosia spp were the fungi species infesting the collected samples. Four fungicides were tested to manage/suppress the mycelial growth of identified fungi species. ResultsMycelial growth of Fusarium, Alternaria, Phoma, Lichenocomium, Penicillium and Aspergillus was significantly inhibited by the application of Chlorothalonil and Procymidone fungicides, while Sulphur proved least effective by inhibiting the mycelial growth of Fusarium spp. ConclusionsThe results revealed that various fungi species infest shisham trees and available fungicides can suppress the growth of these fungi species. Therefore, application of fungicides at appropriate time could lower shisham decline in the country. Nevertheless, field studies are required for further recommendations.

Geographic variation in growth and wood traits of Neolamarckia cadamba in China.

Neolamarckia cadamba is an indigenous, timber-producing tree species in Southern China that plays an important role in the sustainable development of the local forestry industry. However, the geographic genetic variation across its natural distribution area in Southern China has yet to be characterized for best utilization. Here, we report the geographic genetic variation in growth and wood properties of N. cadamba from 10 provenances that represent the entire natural distribution of N. cadamba in Southern China. There was significant geographic variation in diameter breast height (DBH), height (H), volume (V), vessel length (VL), vessel diameter (VD), VL/VD, and wood basic density (WBD). The variation in tree volume across provenances was greater than that of other growth traits, indicating that volume has a greater potential for selection in provenance trials. The provenance heritabilities of growth traits and wood properties ranged from 0.59 to 0.67 and from 0.40 to 0.45, respectively. Trend surface analysis revealed that patterns of geographic variation associated with growth traits were weakly negatively correlated with those of wood properties. The pattern of geographic variation in growth traits showed a gradual increase from the periphery to the central region, whereas wood properties showed the opposite pattern, and latitude had the greatest effect on both. Wood property measurements suggested that the YNMS provenance produced superior timber wood, whereas the GXLZ, GXFCG, and GXNN provenances produced the best pulpwood. These provenances could potentially provide more valuable breeding materials for the genetic improvement of N. cadamba.

Determinants of sustainable building materials (SBM) selection on construction projects

The complexity and fragmented nature and the multiple stakeholders in the construction industry often make it difficult to come up with a firm decision regarding sustainable building materials selection. The wrong choice could negatively impact the project objective and performance outcome. This study assessed the critical factor influencing the choice of sustainable building materials (SBM) selection on construction projects in the Southeast geopolitical zone of Nigeria. Data were collected using a well-structured questionnaire, non-probability (purposive and snowball) sampling techniques, and an internet-mediated survey. Data analyses were carried out using the appropriate descriptive and inferential statistical tools and exploratory factor analysis (EFA). The study revealed recycled plastic, natural clay and mud, stone, bricks and tile, cellulose, stray bales, grasses, limestone, and wood timber, are the commonly used sustainable building materials. Also, their level of awareness is high while their adoption is moderate. EFA revealed that the major clusters of determinants of the choice of green building materials are: emissions minimisation, low running cost and reusability, low thermal and energy consumption efficiency, low cost and high health and safety consideration and waste minimisation. The key factors influencing the choice of sustainable building materials selection in construction are: reducing greenhouse gas emissions from buildings, materially embodied energy cost, operating and maintenance costs, non-toxic or low toxic emissions generated by the products/materials, recyclability of the building materials, availability of the technical skills, renewable (reusable) properties, inhibiting the impact of buildings on the environment, safety and health of the occupants, and appearance and aesthetic. It is recommended that consideration be given to these factors in selecting sustainable/green building materials in the designs and specifications of construction projects.

In vitro propagation from axillary buds of the endangered tree Dalbergia congestiflora Pittier (Fabaceae).

Dalbergia congestiflora Pittier is a woody plant species grown in Mexico and Central America and widely used as timber wood and medicinal material. Since D. congestiflora is an endangered species, an in-vitro micropropagation technique is needed for mass propagation of D. congestiflora plantlets. Nodal segments of D. congestiflora stem cuttings grown in greenhouse conditions were disinfected with an appropriate protocol and in vitro established on Murashige and Skoog medium (MS) supplemented with 0.05 mg l-1 benzylaminopurine (BA). The explants showed 10% contamination with 90% survival, and the initial shoot was regenerated in 90% of them. Axillary buds of 45-day-old initial shoots were cultured on MS containing BA (0, 0.05, 0.1, 0.5, 1, 1.5 and 2 mg l-1) singly or in combination with α-naphthaleneacetic acid (NAA) (0, 0.1, 0.5 and 1 mg l-1). A higher shoot number (9.6 shoots/explant) was obtained on MS with 1 mg l-1 BA and 0.1 mg l-1 NAA. Rooting was investigated using half-strength MS, 2% sucrose and different concentrations of indole butyric acid (IBA) (0, 0.1, 0.5 and 1 mg l-1). After 30 days of culture, developing shoots were elongated and rooted in culture medium without IBA, with production of 3.2 roots/shoot. Micropropagated plantlets of D. congestiflora were successfully transplanted and acclimatized to a mixture of peat moss and perlite (2 : 1) with 100% relative humidity in greenhouse conditions with 80% survival at 30 days of culture. This micropropagation protocol will contribute to the conservation of D. congestiflora, and assure the mass propagation for sustainable usage of this species.

A reliability study concerning the acoustic simulations of timber elements for buildings

Engineered wood constructions and timber buildings are rapidly developing, while the numerical techniques usable for their sound insulation properties are various and often still under development. This research constitutes a first step towards the reliability determination of building acoustics simulations on timber-based elements. A small scale round robin involving five research laboratories is presented. The results obtained show significant deviations depending on the chosen numerical method and indicate how laboratory measurements could not be approximate with a good accuracy. Finally, a sensitivity analysis is presented and challenges as well as requirements for reliable timber structures acoustic predictions are discussed.

Wood description and timber use investigation of Pachyelasma tessmannii (Harms) Harms

Wood description and timber use investigation of Pachyelasma tessmannii (Harms) Harms

Integrating Detailed Timber Assortments into Airborne Laser Scanning (ALS)-Based Assessments of Logging Recoveries

The methodology presented here can assist in making timber markets more efficient when assessing the value of harvestable timber stands and the amounts of timber assortments during the planning of harvesting operations. Information on wood quality and timber assortments is essential for wood valuation and procurement planning as varying wood dimensions and qualities may be utilized and refined in different places, including sawmills, plywood mills, pulp mills, heating plants or combined heat and power plants. We investigate here alternative approaches for generating detailed timber assortments for Norway spruce (Picea abies (L.) H.Karst.), Scots pine (Pinus sylvestris L.) and birch (Betula spp.) from airborne laser scanning (ALS) data, aerial images, harvester data and field data. For this purpose, we used 665 circular plots, and logging recovery information recorded from 249 clear-cut stands using cut-to-length harvesters. We estimated timber assortment volumes, economic values and wood paying capabilities (WPC) for each stand in different bucking scenarios, and used the resulting timber assortment estimates to assess logging recoveries. The bucking scenarios were (1) bucking-to-value using maximum sawlog and pulpwood volumes excluding quality (theoretical maximum), and (2) bucking-to-value using sawlog lengths at 30 cm intervals for Norway spruce and Scots pine and veneer logs of lengths 4.7 m, 5.0 m, 6.0 m and 6.7 m for birch, either excluding quality (the usual business practice) or including quality (a novel business practice). The results showed that our procedure can assist in locating stands that are likely to be more valuable and have the desired timber assortment distributions. We conclude that the method can estimate WPC with root mean square errors of 28.7%, 66.0% and 45.7% in Norway spruce, Scots pine and birch, respectively, for sawlogs and 19.3%, 63.7% and 29.5% for pulpwood.

The complete chloroplast genome sequence of Bambusa albolineata (bambusodae)

Bambusa albolineata (local name: Hua Zhu) is found in Zhejiang, Jiangxi, Fujian, Taiwan, and Guangdong provinces of China, and is often cultivated on low hills, flatlands, and along streams and rivers. Due to its long internodes and flexible material, it is used as timber wood in China. In the current research, the complete chloroplast (CP) genome of B. albolineata was sequenced and reported for the first time. The complete CP genome sequence was 139,326 bp, including a large single-copy (LSC) region of 82,862 bp, a small single-copy (SSC) region of 12,870 bp, and a pair of invert repeats (IR) regions of 21,798 bp. Besides, the plastid genome consisted of 129 genes; having 82 protein-coding genes, 39 tRNA genes, and eight rRNA genes. The overall GC content of the genome was 44.2%. The phylogenetic analysis based on the complete chloroplast genome indicates that B. albolineata is strongly related to B. flexuosa and B. boniopsis.

The Arbitration Panel Ruling on Ukraine’s Certain Wood Restrictions under the EU-UA Association Agreement

On 11 December 2020, the first Arbitration panel ruling in the European Union’s (EU’s) trade dispute under a bilateral preferential trade agreement was issued. This dispute concerns Ukraine’s export restrictions on raw timber and sawn wood of ten specific wood species referred to in the relevant Ukrainian law as ‘rare and valuable species’ and all ‘unprocessed timber’ for a period of ten years. The Arbitration panel found a violation by Ukraine’s ten-year export restriction on all ‘unprocessed timber’ of Article 35 of the Association Agreement between the European Union and the European Atomic Energy Community and their Member States, of the one part, and Ukraine, of the other part (Association Agreement), while justified restriction on ‘rare and valuable species’ under Article XX(b) of the General Agreement on Tariffs and Trade 1994 (GATT 1994), as applied in Article 36 of the Association Agreement. This dispute was not only interesting as the first usage of the EU’s dispute settlement mechanism, but also because of the interpretation of the arbitration panel of ‘World Trade Organization (WTO)-extra’ obligation on the environment contained in the Association Agreement. The article reviews the case as well as analyses the EU’s claim and Ukraine’s defence. Trade law, Environment, EU law, Trade dispute, Arbitration, Dispute settlement, WTO, Export restrictions, Article XX, preferential trade agreement, timber

Ethnobotanical profile of some useful plants and fungi of district Dir Upper, Tehsil Darora, Khyber Pakhtunkhwa, Pakistan

Background: The present study was conducted to explore the ethnobotanical and ethnomedicinal uses of plants in 12 remote villages of Tehsil Darora, district Dir Upper, Pakistan.Methods: Among the residents both, men, and women (some traditional healers like Hakeen and Pansires) were interviewed about the useful plants existing in the area using comprehensive questionnaires.Results: A total of 91 plant species belonging to 37 families were recorded in the four seasons (spring, summer, autumn, winter) in 2019-2020. These included 86 angiosperms (94%) 2 gymnosperms (2%) 2 fungi (2%) and 2 pteridophytes (2%). Asteraceae was the dominant family having 9 species, followed by Lamiaceae (8 species), 6 species of Amaranthaceae, and Cucurbitaceae, Fabaceae (5 species), Euphorbiaceae, and Rosaceae, each with 4 species.Conclusions: The documented plants were used by the local communities medicinally and for other purposes such as fuel, vegetables, fodder, shelter, and timber wood, etc.Keywords: Ethnobotanical plants, Fungi, Tehsil Darora, District Dir Upper, Pakistan

Mid-Holocene Palaeoenvironment, Plant Resources and Human Interaction in Northeast Iberia: An Archaeobotanical Approach

The role of the adoption of farming economies in the transformation of mid-Holocene landscapes in Northeast Iberia is under discussion given that the Neolithization coincides with the cold climatic phase dated ca. 7500–7000 cal BP. The main aim of this paper is to assess whether human activities or climate were the main driver of vegetation changes during the Middle Holocene through the study of the archaeobotanical data from three case studies: Cova del Sardo, La Draga, and Coves del Fem. The application of diverse archaeobotanical techniques to the different plant remains provides a complete picture of the vegetation composition and plant uses. During the early Neolithic, settlement surroundings were intensively exploited for firewood, wood raw material, timber, and plant fibers. The resources were obtained mainly from deciduous and pine forests, depending on the site localization, but also from riparian zones. The diversity of plants exploited was high, not only trees but shrubs and herbs. Evidence of deforestation has been identified in the settlement surroundings in La Draga and Cova del Sardo. The combination of plant exploitation with other agropastoral activities favored the expansion of colonizing species and enhanced biodiversity at a local scale.

Sustainable Development Model of Performance of Woodworking Enterprises in the Czech Republic

The current requirements put on the Member States of the European Union (“EU”) in the area of sustainability and climate-neutral economy through strategic visions such as “Agenda 2030” or “A Clean planet for all” demonstrate the increasing need for quick identification of the changes required in the use of renewable and nonrenewable natural resources. Forests are a particular specific area of such changes. They represent a part of the ecosystem that is important for society from the economic, social, and environmental perspectives. Current climate changes have had a negative effect on the state of forestry in the Czech Republic and have raised many questions of how to ensure its sustainability. Besides the changes in forestry, the situation has also affected the sector primarily depending on the production function of forests and whose coexistence is conditioned. Taking specific sectors as examples, the article presents some prospects that could result in more efficient use of resources and defines potential synergic effects. Analyses of primary and secondary information sources were used to create preferential models (the term “preferential” in the context of the article represents opportunities through which it is possible to achieve an improvement in competitiveness and market advantage over the current model of wood processing and timber trade in the Czech Republic. The model works with potential perspectives and respects the challenges in the field of sustainable development) of timber and wood raw material production and processing and preferential and of economic efficiency (the term “efficiency” in the article represents the technical efficiency of the use of resources to achieve maximum economic benefit and added value. The aim is to increase the economic potential of individual sectors of primary and secondary processing in relation to timber sources) of woodworking businesses. The production model indicates that the energy use of wood, the expansion of the production mix in construction, the use of biomass and digestate in agroforestry, and the logging waste recovery are the most prospective sectors. The model presenting preferential areas in the woodworking industry development with respect to sustainability identified the need to increase associated production and material efficiency in construction and energy sectors, as well as insufficient activity of the sectors associated with technological innovations, FSC and PEFC certification prospects, bioeconomy and circular economy, a considerable need for wage growth in the sector and increased use of the existing production capacities by both domestic and foreign sales.

Development of Timber Buckling Restrained Brace for Mass Timber-Braced Frames

This research presents the development of a mass timber buckling restrained brace (T-BRB) that combines a low yield strength steel core with a mass timber casing to create a new ductile fuse. The T-BRB is an essential element of a mass timber buckling restrained braced frame (BRBF), which is a promising mass timber wood lateral force–resisting system. Critical elements of T-BRB design that are important for good performance include casing stiffness, casing material, number and spacing of bolts, timber spacer and casing gap, steel core yield strength, and friction between steel core and casing interface. Compressive tests on engineered wood blocks using glued laminated timber, laminated veneer lumber, parallel strand lumber, and mass plywood panel (MPP) were conducted to determine elastic stiffness, maximum load, and ultimate displacement. MPP loaded parallel to the wide face of laminations (X-direction) outperformed other materials with respect to high elastic stiffness, which is an important property of the casing because it controls buckling of the steel core. Six 3.66 m (12 ft)–long T-BRBs with a targeted yield strength of 274 kN (61.5 kip) were tested utilizing three T-BRB casing designs with varying MPP lamination layups. A 3.9% strain was achieved under a strain-based loading protocol. For a fatigue-based loading protocol, after two cycles at 2.0% strain, more than 26 additional cycles at 1.5% strain were attained. The hysteresis curves for all six T-BRBs remained stable throughout the tests and the cumulative inelastic deformation exceeded two times the value required by the standard.

Bhutias of Sikkim

Bhutias of Sikkim, animal husbandry alone was not sufficient to sustain the population, so they indulged in marginal trading activities with the Tibetan across the borders. The barter of timber wood, dye stuffs and dairy products of that region for Tibetan salt and wool formed the basis of this trade. Bhutias of Sikkim (Lachung and Lachen) pursued it as an occupation intimately interwoven with pastoral activities. Thus, the trade was as long as unhampered by political restrictions, it enabled them to remain economically independent. However with the closing of the bordering 1962, social life changed of these people. Political events beyond their have led to the transformation of their traditional economic system, forcing them to reorient it. They lost large herds of yaks and sheep, when they were on the seasonal migration under the ancient trans-border pasture usage agreements. They could no longer use pasture land in Tibet, causing heavy losses of their herds due to lack of alternative pasture area. Bhutias started to shift from a pastoral and trading economy to a more settled agricultural and small scale horticulture and wage earning economy. The seasonal migration emerges as an activity organized by family and community structure. The Bhutias of Sikkim have adopted culturally to diverse natural landscapes and have established settlement patterns and production activities tailored to the limitation imposed by the region.

Effects of density on colour and gloss variability changes of wood induced by heat treatment

AbstractThe influence of heat treatment severity (resulting from temperature) on the colour and gloss distribution changes of mahogany wood, and the effects of wood density on the responses to heat treatment were evaluated. The wood timbers with different densities were treated at 150°C to 200°C with an interval of 10°C and duration of 4 hours for heat treatment schedules. The colour parameters (lightness L*, red‐green axis value a*, yellow‐blue axis value b*) and gloss (parallel and perpendicular to the grain) values of heat‐treated wood were determined. The distributions of colour and gloss were analyzed using a frequency counts method. Results show that heat treatment resulted in the distinct decrease in L* and b*, while almost no change in a* for mahogany wood. The lower gloss values were obtained in the wood after heat treatment. The colour and gloss uniform on the exposed surface of the wood was improved due to heat treatment. Heat‐treatment induced colour and gloss changes were more effective in the samples with lower density. The effects of density on the colour and gloss variability in the original wood were reduced by heat treatment, and this reduction was more distinct at high heat treatment temperature. The total gloss change was found to be highly correlated with the total colour change of heat‐treated wood.

A cost effective strategy to fabricate STA@PF@Cu2O hierarchical structure on wood surface: aimed at superhydrophobic modification

Cuprous oxide nanoparticles (Cu2O NPs), phenol formaldehyde (PF) resin, and stearic acid (STA) were used to fabricate hierarchical core/shell structures to endow wood with superhydrophobic function, in which the preparation of Cu2O NPs and the synthesis of PF were carried out simultaneously in one system. The Cu2O NPs with the shape of a symmetrical tetrahexahedron were prepared in this work, and this novel shape is beneficial for creating a superhydrophobic surface. A relatively rough structure in micro/nanoscale was formed on the wood surface after being sprayed with PF@Cu2O coating, which played a vital role in the fabrication of superhydrophobic wood surfaces, as expected. Morphological analysis and surface free energy calculations verified that STA reduced the surface free energy. Application of 12 layers of PF@Cu2O coating followed by 2 h immersion in STA ethanol solution produced wood surfaces with low water permeability and high water contact angles of 153.3°, 153.2°, 150.5° on cross, radial, and tangential sections, respectively. Abrasion tests coupled with subsequent exposure to acidic and alkaline conditions indicated that the coating was resistant to both mechanical wear and chemical degradation. This two-step coating strategy used inexpensive ingredients and could have potential to application as water repellency protection of wood timber.