The objective of this study was to evaluate the remediation of water containing the insecticide chlorpyrifos by using constructed wetlands (CW) cultivated with Polygonum punctatum, Cynodon spp. and Mentha aquatica, operated under different hydraulic retention times: 24, 48, 96, 144 and 192 h. The system efficiency was based on reduction of the initial concentration of chlorpyrifos and toxicity of the contaminated water. The results showed that constructed wetlands are an excellent alternative for remediation of the insecticide chlorpyrifos in aqueous medium. It was observed that the average overall removal efficiency of the insecticide was 98.6%, and in the first hydraulic retention time, 24 h, chlorpyrifos was removed to levels below the detection limit in all CW. This result is mainly attributed to adsorption and microbial degradation. For the qualitative standard acute toxicity tests with Daphnia similis, for most samples there was a reduction in toxicity greater than 80%. It was reported that the ecotoxicological tests with the effluents of the constructed wetland are a good option as an indicator of the effectiveness of treatments and a promising alternative to complement the physical and chemical analyses.

This study aimed to evaluate the pH, phosphate, and nitrate in the process of arsenic absorption by Eichhornia crassipes (water hyacinth), using the surface response methodology, in order to optimize the process. The plants were exposed to a concentration of arsenic of 0.5 mg L⁻¹ (NaAsO₂) over a period of 10 days. The results indicated optimal levels for the absorption of arsenic by E. crassipes at pH equal to 7.5, absence of phosphate, and minimum nitrate level of 0.0887 mmol L⁻¹. For the tested concentration, E. crassipes was able to accumulate 498.4 mg kg⁻¹ of As (dry base) in its plant tissue and to reduce 83% of the initial concentration present in the aqueous medium where it was cultivated. The concentration of phosphorus in solution linearly increased the phosphorus content in the plants and negatively influenced the absorption of arsenic. The concentration of 0.5 mg L⁻¹ of As did not significantly affect the relative growth rate (RGR) and the tolerance index (TI). 94% of As (III) initially solubilized in water was converted by the end of the experiment period into As (V). The water hyacinth was important in the phytoremediation of arsenic when cultivated under optimal conditions for its removal.

Constructed wetlands are nature-based technologies widely used for the treatment of wastewater and contaminated surface water. This study evaluated the efficiency of free water surface (FWS) and horizontal subsurface flow (HSSF) constructed wetlands in reducing the turbidity of mine spoil rainwater using the w-C* model. Different hydraulic retention times (2, 4, and 6 days) were tested, and the influence of macrophyte type and substrate on the w parameter was investigated. Model calibration was performed based on correlation coefficients (R), coefficient of determination (R²), Nash–Sutcliffe efficiency (NSE), and root mean square error (RMSE). The results indicated a 99% reduction in turbidity, with average values of R = 0.87 ± 0.05 (FWS) and 0.87 ± 0.03 (HSSF), and NSE of 0.76 ± 0.04 (FWS) and 0.74 ± 0.07 (HSSF), demonstrating good agreement between observed and predicted data. The settling rate (w) ranged from 0.16 to 0.40 m·d⁻¹ in FWS and from 0.20 to 0.70 m·d⁻¹ in HSSF, with the lowest value recorded in the control (0.09 m·d⁻¹). The best performances were observed in FWS-P with Pistia stratiotes (0.40 m·d⁻¹) and HSSF with Typha domingensis (0.70 m·d⁻¹), demonstrating that vegetation, combined with the use of medium-grain substrate (9.5–19.0 mm), enhances turbidity removal. The w-C* model proved to be a robust tool for describing the kinetics of suspended colloidal particle removal in constructed wetlands, providing valuable insights for optimizing hydraulic parameters and design criteria for full-scale application.

Na engenharia, o sistema de revestimento cerâmico está entre os mais empregados na Construção Civil, devendo, entre tantas outras funções, garantir a impermeabilidade dos ambientes na edificação e fornecer um acabamento estético. Contudo, as causas de falhas de patologias nesse tipo de sistema estão relativamente ligadas à execução do revestimento. Desse modo, com as técnicas de investigação sendo aprimoradas, surge a engenharia investigativa, cujo foco é voltado para a apuração destas falhas construtivas. Nesse viés, o presente trabalho teve como objetivo aplicar um questionário em ambiente virtual, de maneira a coletar informações acerca do procedimento executivo de perícias em revestimento em sistema de revestimento de piso com placas cerâmicas. Para a pesquisa, foram utilizados quatorze peritos, entre servidores públicos e peritos particulares. Para a coleta das informações, elaborou-se um questionário de entrevista do tipo qualitativa e estruturada, a qual foi dividida em duas partes. A primeira parte teve como intuito obter dados sociodemográficos a respeito da atuação dos peritos. A segunda parte foi composta de cinco questões dissertativas, envolvendo o tema trabalhado. Para a discussão dos resultados, foi realizada a comparação entre as informações fornecidas pelos peritos e a literatura e as normas vigentes no país. Os resultados e discussões da pesquisa indicaram que os respondentes, profissionais da engenharia legal, embora não citassem as normativas ou doutrinas, apresentaram conhecimento que, de certa forma, estava de acordo com as regulamentações. Ainda, o uso do ambiente virtual se mostrou ser uma alternativa viável, de maior praticidade para se obter respostas de profissionais de diferentes localidades no país.