ABSTRACT CLT (Cross Laminated Timber) is a pre-fabricated engineered wood panel, generally made from conifer woods, mainly pine and spruce. Due to the low natural resistance of this species to ...deteriorating organisms attack, the Brazilian standard ABNT NBR 7190:1 (2022) orients the treatment of structural elements before being used. This study aimed to evaluate the resistance of woods from Pine and Spruce species, with different preservative treatments and retentions, against wood termite (Cryptotermes brevis) attack. Different species of Pine and Spruce (Pinus abies, Pinus sylvestris, Pinus elliottii e Pinus taeda) were evaluated, as well as different preservatives such as Impralit KDS-B, CCA (Chromated Copper Arsenate), CCB (Copper Borate Chromated), MCA-C (Micronized Copper Azol type C) and HQC 791 (fire retardant for wood), usually used in Brazil, the United States and Europe. The results demonstrated that the fire retardant induced greater resistance to attack by xylophagous organisms, with total insect mortality and no surface deterioration after 45 days of testing. The CCA preservative also demonstrated efficiency in wood treatment with high resistance to termite attack, high mortality and only superficial wear of the specimen. It was concluded, therefore, that preservative treatments are recommended to guarantee the durability of the constructive system so that the so-called engineered wood elements can be used as structural systems.
RESUMO CLT (Cross Laminated Timber) é um painel de madeira engenheirado pré-fabricado, geralmente feito de madeiras de coníferas, principalmente pinus e abeto. Devido à baixa resistência natural desta espécie ao ataque de organismos deteriorantes, a norma brasileira ABNT NBR 7190:1 (2022) orienta o tratamento de elementos estruturais antes de serem utilizados. Este trabalho teve como objetivo avaliar a resistência de madeiras das espécies Pinus e Spruce, com diferentes tratamentos conservantes e retenções, ao ataque do cupim xilófago (Cryptotermes brevis). Diferentes espécies de pinus e abeto (Pinus abies, Pinus sylvestris, Pinus elliottii e Pinus taeda) foram avaliadas, bem como diferentes conservantes como Impralit KDS-B, CCA (Chromated Copper Arsenate), CCB (Copper Borate Chromated), MCA- C (Azol de Cobre Micronizado tipo C) e HQC 791 (retardante de fogo para madeira), normalmente utilizados no Brasil, Estados Unidos e Europa. Os resultados demonstraram que o retardante de fogo induziu maior resistência ao ataque de organismos xilófagos, com mortalidade total dos insetos e sem deterioração da superfície após 45 dias de teste. O conservante CCA também demonstrou eficiência no tratamento da madeira com alta resistência ao ataque de cupins com alta mortalidade e desgaste apenas superficial do corpo de prova. Concluiu-se, portanto, que para garantir a durabilidade do sistema construtivo são recomendados tratamentos preservativos para que os chamados elementos de madeira engenheirada possam ser utilizados como sistemas estruturais.
Various natural products are potentially suitable for wood protection, particularly against fungi attack. Caffeine is a well-known compound of natural origin, commercially and economically available, ...which could facilitate its future use for wood protection. This work investigated the antifungal resistance of the sapwood of Scots pine (Pinus sylvestris L.) treated with a water solution of caffeine and then thermally modified. The samples after impregnation were thermally modified at different temperatures selected on the basis of thermogravimetric analysis (TGA) of caffeine. The paper presents preliminary results of resistance of treated pinewood towards Aspergillus niger van Tieghem (ATCC 6275). The treated samples were subjected to both a leaching procedure and to the artificial aging procedure imitating natural weather conditions. Thermal modification of wood treated with caffeine improved the fungistatic properties of samples after artificial aging. It occurred through partial elimination of caffeine leaching from the wood structure.
•Copper azole impregnation adversely affected MUF-bond in E. grandis joints.•Mechanical pre-treatment significantly influenced the bondline durability.•Increased bonding pressure was vital for ...improved bondline quality.•Treated and laminated E. grandis for structural applications is feasible.
The effect of copper azole impregnation, wood density, adhesive spread rate, mechanical pre-treatment, open and close assembly times, bonding pressure, and press duration on melamine-urea–formaldehyde-bond performance of Eucalyptus grandis joints was investigated. The results obtained showed that the shear strength was mainly affected by copper azole concentration and bonding pressure while wood failure and delamination were mainly affected by wood density, copper azole concentration, and mechanical pre-treatment. With the adaptation of bonding parameters, results suggest that satisfactory improvement of melamine-urea–formaldehyde-bond performance in copper azole-treated E. grandis laminates is feasible. This will make the production of treated hardwood laminated composites for structural applications in tropical and sub-tropical regions attainable.
► As and Cr polluted soil was successfully amended with iron water treatment residues. ► Adding 5% amendment reduced the leaching of As and Cr in batch experiments. ► 2.5% amendment reduced As in ...pore water by two orders of magnitude in the field. ► The field experiment revealed pseudo-gley conditions in the soil.
An iron-rich water treatment residue (WTR) consisting mainly of ferrihydrite was used for immobilization of arsenic and chromium in a soil contaminated by wood preservatives. A leaching batch experiment was conducted using two soils, a highly contaminated soil (1033
mg
kg
−1 As and 371
mg
kg
−1 Cr) and slightly contaminated soil (225
mg
kg
−1 As and 27
mg
kg
−1 Cr). Compared to an untreated reference soil, amendment with 5% WTR reduced leaching in the highly contaminated soil by 91% for Cr and 98% for As. No aging effect was observed after 103
d. In a small field experiment, soil was mixed with 2.5% WTR in situ. Pore water was extracted during 3
years from the amended soil and a control site. Pore water arsenic concentrations in the amended soil were more than two orders of magnitude lower than in the control for the upper samplers. An increased release of arsenic was observed during winter in both fields, mostly in the deepest samplers. This is likely due to the formation of a pseudo-gley because of precipitation surplus. Stabilization of arsenic and chromium contaminated soil using WTR is a promising method but the transformation of ferrihydrite in soil proves a concern in case of waterlogged soils. Still the amendment minimized the leaching of arsenic, even in cases of seasonal releases.
Wood preservation plays a vital role in maintaining wood products' structural and aesthetic properties. Traditional methods, including chemical treatments, preservatives, and coatings, have been ...utilized for wood protection, but sustainable alternatives are sought due to their negative environmental and health impacts. The utilization of nanomaterials presents a promising avenue for wood protection. In this study, nanoparticles were applied to lignocellulosic materials using the impregnation method to enhance solid wood’s water and fire resistance without needing additional energy. This research aimed to identify a cost-effective and energy-efficient approach for large-scale wood production while introducing innovative and competitive materials in the wood industry. Surface modification and characterization analyses, including SEM-EDX and Optical Profilometer studies, TGA-DTA analysis for thermal strength assessment, % water uptake test for water resistance evaluation, and PCE-CSM 10 spectrophotometer measurements to determine color change parameters, were conducted. Functionalized wood surfaces treated with zinc oxide (ZnO), chitosan (Ch), and tin dioxide (SnO2) nanoparticles exhibited water uptake values of 64%, 71%, and 73%, respectively. Following the salinization process using TEOS, the water uptake values decreased to 58%, 59%, and 60% for the respective surfaces. Based on the TGA and DTA results, the W-ZnO-TEOS sample demonstrated superior mass protection, with a significant weight loss of 62.1% (5.717 mg) at 340-375°C and 14.4% (1.328 mg) at 381-439°C. This was followed by the W-SnO2-TEOS sample, which exhibited a weight loss of 46.3% (7.050 mg) at 301-353°C and 15.4% (2.345 mg) at 431-469°C. The W-Ch-TEOS sample displayed a weight loss of 66.4% (8.242 mg) at 342-365°C and 18.8% (2.335 mg) at 448-476°C. Overall, the W-SnO2-TEOS sample demonstrated the highest water resistance, while the W-ZnO-TEOS sample exhibited the most effective fire protection capabilities.
A new species of the yeast genus
Blastobotrys
was discovered on ancient ship timbers in the Netherlands. The species had developed on the wood of a river barge dating to the Roman period. The growth ...occurred after the preservative polyethylene glycol (PEG 4000) was washed out of some of the timbers due to an undetected leak in the storage unit. Mycological analysis of various timber samples revealed the presence of
Microascus melanosporus
(predominant),
Microascus paisii
, a member of the
Acremonium chrysogenum
-clade, and a new
Blastrobotrys
species. The new species produced sporothrix-like conidiophores with clavate blastoconidia (3–7 × 1–3.5 μm) and was found to be osmotolerant, capable of growth on low water activity media like malt yeast 50% glucose agar (MY50G). In this article we formally describe and introduce
Blastrobotrys nigripullensis
(CBS 17879
T
) based on its morphology, physiology and phylogenetic placement.
Wood vinegar is a natural organic pesticide that is effective against plant diseases and harmful insects and is used in agriculture in particular for the improvement of plant and soil quality.In ...different application areas, wood vinegar provides effective protection against various harmful bacteria, fungi, and insects.Based on its demonstrated protection as a pesticide and antifungal, this study aimed to use wood vinegar as an impregnation agent in wood materials. For this purpose, using the full-cell process, Pinus sylvestris and Fagus orientalis samples were impregnated with concentrations of 1 %, 5 %, 3 % and 6% oak wood vinegar, obtained via the pyrolysis of sessile Quercus petraea. wood at 350 °C.The samples were then subjected to tests for brown-rot (Serpula lacrymans) and white-rot (Trametes versicolor) fungi, for Hylotrupes bajulus (Coleoptera: Cerambycidae) larvae, and for three different mold fungi (Aspergillus niger Tiegh JAG-04-1003, Penicillium brevicompactum Dierckx FS-31, and Trichoderma harzianum Rifai FS-19). According to the results, the wood vinegar was found to exhibit antifungal, antimold, and larvicidal properties and consequently, could be used effectively in wood protection.
Wood in marine environments requires protection against xylophagous, and to increase the effectiveness of the preservatives, it is first necessary to know environmental conditions and species of wood ...borers present. The durability of treated
wood against the attack of marine borers in different environments was investigated, with (1) burnt oil, by the hot-cold bath method; (2) paraffin, by the Bethell method; (3) superficial burning of the wood with oil application, known as shou sugi ban technique; and (4) impermeable rubber, with and without the addition of silica, by immersion. The experiment was adapted from the standard
and carried out in three areas, one located in a river and two in estuarine coastal areas of the Paranaguá Bay (Brazil). Based on the percentage of lost wood area, the treatment with impermeable rubber with the addition of silica showed the best performance at the local 1 site (26.3%). At the local 2 site, treatments with impermeable rubber with and without the addition of silica had the lowest percentages of loss, with mean values of 13.95 and 12.65%, respectively. The other treatments had losses above 30%, being classified as severe damage, meaning they are not suitable for this use.
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