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Domestic laundry wastewater discharge contributes significantly to the presence of microfiber and surfactant pollutants in aquatic ecosystems, which have detrimental and toxic effects on humans and the environment. Investigating the efficacy of powdered activated carbon (PAC) in removing micro-/nanofibers with or without surfactant from household laundry effluent is the purpose of the current research. To simulate real-world scenarios, PAC adsorption kinetics and isotherms in laundry effluents under controlled conditions were studied. These studies showed that the kinetics obeyed a pseudo-second-order process and the isotherms varied between Langmuir and Freundlich models depending on the water types. In the results of experiments using distilled water and tap water, it was observed that the adsorption capacity was higher in tap water. When the adsorption of 0.1 µm filtered synthetic garments, detergent, and tap water was compared with the adsorption of the raw sample, it was observed that the adsorption capacity of the 0.1 µm filtered version was higher. Even though this study is preliminary, the results indicate that PAC has the capacity to serve as a viable approach for mitigating micro-/nanoplastic and surfactant contamination from laundry wastewater, thereby offering valuable guidance for advancing eco-friendly laundry techniques.
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Carvão Vegetal , Tensoativos , Humanos , Ecossistema , Águas Residuárias , Pós , ÁguaRESUMO
In the study, sol-gel based TiO2 nanoparticles (NPs) were doped by Cu(II), and the surface of cotton fabric was coated with Cu-doped TiO2 NPs to develop self-cleaning and antibacterial properties. Coffee stains were introduced on the modified cotton fabric and under suntest illumination; a decrease in the color of coffee stain was followed over time via K/S value to determine self-cleaning performance. The photocurrent in a photoelectrocatalytic reactor was measured to evaluate the photocatalytic effect of Cu(II) doping. TiO2 NPs showed self-cleaning and antibacterial effects under UV-illuminated conditions. However, no effects were observed under dark (non-illuminated) conditions. The modified textiles with Cu(II) doped TiO2 NPs showed antibacterial activity against E. coli under light and dark conditions. Under the 2 h illumination period, fluctuating color changes were observed on the raw cotton fabric, and stains remained on the fabric while 78% and 100% color removals were achieved in the cotton fabrics coated by Cu doped TiO2 NPs in 1 h and 2 h, respectively.
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Escherichia coli , Titânio , Antibacterianos/farmacologia , TêxteisRESUMO
Concept Development [CD] in the early years cannot be complete without teachers' support. However, limited research exists. This research aimed to assess CD classroom interactional quality and its relationship with other quality dimensions/domains and children's overall development using the data collected in State Pre-K/Head Start classrooms with Pre-K CLASS and LAP-3. Data collected from 171 classrooms underwent analysis with Python and SPSS. Pre-K CLASS scores showed that with the exception of one high-quality classroom, all other classrooms were categorized as either mid-quality or low-quality CD. Moreover, most teachers showed lower interactional quality not only in the CD dimension but also in the Quality of Feedback [QF] and Language Modeling [LM] dimensions of Instructional Support [IS], than in the dimensions of Emotional Support [ES] and Classroom Organization [CO] domains. The results indicated that CD, QF, and LM quality dimensions did not differ across the classrooms or districts. However, ES, CO, and IS domains differed significantly. While the observed differences for ES and CO were similar between the two districts, District 1 had higher mean IS scores than District 2. Furthermore, LAP-3 scores of 2514 children showed that 26.7 % of children scored below the expected level in cognitive development and 35.5 % scored below in language development by the end of the school year, with a higher proportion of male children falling in this category. Nonetheless, children attending State Pre-K/Head Start classrooms demonstrated an average gain of 4 months beyond their chronological age. The multi-level regression analysis of Pre-K CLASS and those LAP-3 scores showed no statistically significant relationship between interactional quality and children's developmental progress. Children in mid-quality CD classrooms showed slightly more progress in all areas of development, except in personal/social, compared to children in low-quality CD classrooms. Similarly, children in mid-quality IS classrooms outperformed those in low-quality IS classrooms in all LAP-3 areas except personal/social and pre-writing as well. In conclusion, the current research suggests that many teachers struggle not only to effectively provide high-quality CD teacher-child interactions but also high-quality IS teacher-child interactions in their classrooms. Comprehensive in-service training on CD and an alternative assessment tool that extends beyond the 72-month age limit are strongly recommended. This is important to ensure that teachers are equipped with the necessary skills and motivation to provide high-quality education to young children to prevent developmental delays in children.
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Intervenção Educacional Precoce , Instituições Acadêmicas , Humanos , Masculino , Pré-Escolar , Escolaridade , Desenvolvimento da Linguagem , Desenvolvimento InfantilRESUMO
Corrosion constitutes a significant issue in industries that handle metals. Corrosion inhibitors with a low impact on the environment provide a significant economic benefit in various engineering applications. In this work, the effectiveness of olive leaves extract is evaluated as a cost-effective and environmentally-friendly corrosion inhibitor. The corrosion of carbon steel in different concentrations of hydrochloric acid (0.1, 1.0, and 2.0 M) when protected by an aqueous solution of olive leaf extract of concentrations ranging from 10 to 60 ppm is investigated. A green extraction process based upon water extraction is used to ensure minimum impact on the environment. Results show that the corrosion inhibition efficiency increased as the concentration of the olive leaf extract increased. An analysis of variance showed a significant effect of acidic molarity, temperature, and inhibitor concentration on the corrosion rate. A significant statistical model indicates that the inhibitor exhibits higher efficiencies at higher acidic molarity. Results of SEM and EDX also demonstrated that a protective film of the inhibitor on the specimen surface plays a role in corrosion inhibition, suggesting that the inhibitor molecules are adsorbed at the interface between the carbon steel and the acid solution. The study provides an insight on the corrosion mechanism and highlights the potential of olive oil extract as an eco-friendly alternative to traditional corrosion inhibitors.
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This paper presents a novel approach to utilizing agricultural waste. It compares three different applications for cotton stalks: fabrication of wood composites, bioethanol production, and biogas cradle-to-gate Life cycle assessment production processes. Cotton cultivation generates a lot of debris, mostly cotton stalks, which are incinerated or landfilled, Sustainable resource management is critical for maintaining the ecosystem, and economic stability, and promoting social fairness since it ensures the long-term availability of resources while minimizing environmental damage. The investigation uses the Ecological Footprint, Impact 2002 +, Global Warming Damage Potential, Greenhouse Gas Protocol, Recipe Midpoint, Ecosystem Damage Potential, and CML IA Baseline-open LCA-enabled environmental sustainability assessments. The analysis showed that bioethanol has a lower carbon footprint and climate change impact than both wood composite and biogas production processes, as a result, this could cause a preference for bioethanol production as an environmentally friendly strategy for cotton stalks utilization. While human toxicity was higher in the biogas production process, it emits less fossil CO2 than biogenic CO2. The total climate change of wood composite, bioethanol, and biogas production processes was 0.01761, 0.011300, and 0.01083 points, respectively. This research helps accomplish wider ecological and economic aims by giving insights into sustainable waste management practices.
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Biocombustíveis , Ecossistema , Humanos , Animais , Dióxido de Carbono , Pegada de Carbono , Estágios do Ciclo de VidaRESUMO
In this study, a novel photoelectrocatalytic membrane (PECM) reactor was tested as an option for the desalination, disinfection, and detoxification of biologically treated textile wastewater (BTTWW), with the aim to reuse it in hydroponic farming. The anionic ion exchange (IEX) process was used before PECM treatment to remove toxic residual dyes. The toxicity evaluation for every effluent was carried out using the Vibrio fischeri, Microtox® test protocol. The disinfection effect of the PECM reactor was studied against E. coli. After PECM treatment, the 78.7% toxicity level of the BTTWW was reduced to 14.6%. However, photocatalytic desalination during treatment was found to be slow (2.5 mg L-1 min-1 at 1 V potential). The reactor demonstrated approximately 52% COD and 63% TOC removal efficiency. The effects of wastewater reuse on hydroponic production were comparatively investigated by following the growth of the lettuce plant. A detrimental effect was observed on the lettuce plant by the reuse of BTTWW, while no negative impact was reported using the PECM treated textile wastewater. In addition, all macro/micronutrient elements in the PECM treated textile wastewater were recovered by hydroponic farming, and the PECM treatment may be an eco-safe wastewater reuse method for crop irrigation.
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The efficiency of TiO2 as a catalyst in the ozonation of humic acid (HA) was evaluated in a comprehensive manner. Ozonation, catalytic ozonation and adsorption experiments were conducted using both synthetic HA solution and natural water. HA degradation was evaluated in terms of DOC, VIS400 and UV254. It was shown that the addition of catalyst positively affects the mechanism of ozonation. An increase in HA degradation was observed for all these parameters. The impact of catalyst dose and initial pH value of HA on the efficacy of catalytic ozonation was investigated. The highest removal efficiencies were achieved with the dose of 1 g l(-1) of TiO2 (Degussa P-25) and in the acidic pH region. The catalytic ozonation process was efficient also on natural water component although not at the same level as it was on synthetic water. The adsorptive feature of P-25 was considered to have a clear evidence of the catalytic ozonation mechanism. The mechanism of catalysis on the surface of metal oxides was elucidated with the help of quantum-chemical calculations. In the framework of Density Function Theory (DFT), the O3 decomposition was calculated in the catalytic and non-catalytic processes. Donor-acceptor properties of the frontier (highest occupied and lowest unoccupied molecular orbitals, HOMO/LUMO) orbitals are discussed. Electron density distribution and reaction mechanism of superoxide particles formation, which participate in the process of HA ozonation are analyzed.
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Substâncias Húmicas/análise , Modelos Químicos , Ozônio/química , Titânio/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Adsorção , Catálise , Água Doce/química , Concentração de Íons de Hidrogênio , Nanopartículas/química , OxirreduçãoRESUMO
The aim of this paper was to investigate the feasibility of the removal of phosphate from aqueous solution by electro-coagulation (EC). The current density (CD) between 2.5 and 10 mA cm(-2) and duration in the limits of 5-20 min were tried for different concentrations. In order to determine optimal operating conditions, the EC process used for the phosphate removal was examined in dependence with the CD, initial concentrations and time. The results of the experimental batch processing showed high effectiveness of the EC method in removing phosphate from aqueous solutions.