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The use of preservatives such as diuron and isoproturon in the paint industry is essential to protect products against microbial attack. However, these compounds are subject to strict regulation due to the harmful effects they have on the environment and human health. Therefore, analytical strategies to control the production process at paint plants are fundamental to ensure suitable products. In the present work, a low-cost portable square-wave voltammetry device with commercial screen-printed electrodes was proposed to control the starting products and to determine isoproturon and diuron levels in manufactured paint products. Under the optimized conditions (electrolyte HClO4 0.18 M, nickel oxide-doped carbon electrodes, ESW = 0.02 V, Estep = 0.0015 V, and ƒ = 15 Hz), the results indicated satisfactory analytical performance, with detection limits of 3.5 and 3.0 mg L−1 for isoproturon and diuron, respectively, and precision lower than 7.5% for both biocides. The analytical strategy employed to achieve satisfactory selectivity involved taking advantage of the specific interaction of cysteine with 1,2-benzisothiazol-3(2H)-one (BIT) as a potential interferent in some commercial products and the use of matrix match calibration. A recovery study provided values in the range of 92–104% for accuracy validation. A sample pretreatment step was needed due to the paint composition, and a miniaturized method was proposed here. The novelty of this method lies in the use of a portable voltammetry device in real-world industrial applications to control the paint production process using a cost-effective, time-saving, sustainable, and green protocol. The HEXAGON tool is used for assessing greenness and sustainability. The choice of reagents like HClO4 and the minimization of waste from the small volumes used align with the principles of using safer solvents, a key concern in green and sustainable chemistry.

The permeability of Norway spruce wood can be reduced to 1–5% of that of green timber when dried, resulting in only slight radial penetration of chemical solutions. We investigated the penetration of the biocide 3-iodo-2-propynyl butylcarbamate, (IPBC) in Norway spruce and Scots pine sapwood when applied in a water-based coating system. Penetration of both untreated wood and specimens pretreated with the white-rot fungus Physisporinus vitreus was analyzed by the absence or presence of blue staining after incubation with Aureobasidiumpullulans and Sclerophoma pithyophila. The qualitative results were compared with quantitative data obtained by chemical analysis. It was assumed a pre-treatment with Physisporinus vitreus could make the surface of the substrate more porous and improve the penetration of fluid substances. All analytical investigations of the samples were done after an outdoor weathering period of 6 months. From a practical point of view the performance of the coated substrate is more relevant after a certain aging procedure then right after the application. The chemical measured uptake of IPBC for Scots pine was similar for all samples at the surface. The penetration depth was higher for those samples with a pre-treatment with Physisporinus vitreus. The colonization pattern of the samples by blue-stain fungi depended upon the pre-treatment but did not show a clear correlation between IPBC-content and staining. The cross-section of the samples with pre-treatment was completely stained, the cross-section of the samples without pre-treatment did show a distinctive blue stain-free zone. In Norway spruce, the chemical measured uptake of IPBC was similar for all samples at the surface independent of the pre-treatment. The penetration depth was higher for those samples with a pre-treatment with Physisporinus vitreus. But a clear visible colonization by blue-stain fungi was only observed for the samples with a pre-treatment with Physisporinus vitreus. The samples without pre-treatment were locally stained across the entire cross-section. As with the Scots pine, a clear correlation between IPBC-content and blue staining was not visible, following comparison of the samples with and without pre-treatment with Physisporinus vitreus. The results suggest that not only the presence of IPBC influences colonization by A.pullulans and S.pithyophila, but also a range of other factors in wood pre-treated with P. vitreus.

The impacts of impregnation and bleaching on the varnish layer hardness of Oriental beech (Fagus orientalist L.) wood were investigated. A number of bleaching combinations [NaOH−H2O2], [NaOH−Ca(OH)2−H2O2], [NaOH−MgSO4−H2O2] [NaHSO3−H2C2O4], [NaSiO3−H2O2], [KMnO4+NaHSO3+H2O3] were applied at 18% concentration for bleaching to both impregnated and unimpregnated specimens of Oriental beech wood. Subsequently, water-based (WB) varnish was coated over the samples and the varnish layer hardness values were determined in accordance with ASTM D 4366-95.All of the chemicals used for bleaching reduced the surface hardness. However, after varnish coating, the hardness of most samples was similar to that of the varnish-coated natural (control) samples.