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The present work describes the chemistry and mineralogy of soils such as Terra Preta Arqueológica (TPA) or Terra Preta de Índio (TPI) from the Bitoca I and II sites, located in the Salobo Region (Carajás Mineral Province, Pará‐Brazil). The results revealed chemical and mineralogical characteristics that are similar to other TPAs found throughout the Amazon region, such as relatively high levels of Ca (average of 3600 ppm), P (average of 850 ppm), Mn (average of 730 ppm), Zn (average of 55 ppm), and Cu (average of 63 ppm). In soils related to the characteristics of occupation by huts and campfires, the mineralogical composition is represented by quartz, kaolinite, calcite, muscovite, anatase, hematite, goethite, and gibbsite. Amorphous phases have also been identified mainly as calcium phosphates and organic matter (humic and fulvic acids). The analysis of the features/structures described here helped in the identification/verification of areas destined for different activities within the sites. [ABSTRACT FROM AUTHOR]

The rising concern about the environmental pollution, particularly due to the setup of more industrial sectors has grabbed the attention of scientists and researchers. Many textile businesses emit Malachite Green and Methylene Blue (MG and MB) into the atmosphere, posing serious health risks. In this study, a copper metal-organic framework doped with iron nanoparticles (Cu-MOF@Fe3O4) was synthesized utilizing the slow evaporation approach, commencing with cuprous chloride and 2-mercaptobenzimidazole in a 1:2 ratio. Cu-MOF@Fe3O4 was characterized using a variety of techniques, including FTIR, SEM, and DRS analysis. The SEM analysis showed a rough and uneven morphology for the Cu-based MOFs. The XRD analysis confirmed the crystallinity of the products. The average crystallite size for Cu-MOF, Fe3O4 nanoparticles and Cu-MOF@Fe3O4 were found to be 0.22, 1.00, and 1.00 nm. While the surface area of Cu-MOF was found to be 213.192 m2g−1 while in Cu-MOF@Fe3O4 it shows an increase, i.e., 218.268 m2g−1 as calculated through the iodometric method. A series of experiments were conducted to assess the surface area, chemical oxygen demand (COD), limit of detection (LOD) (0.065559, 0.0136), limit of quantification (LOQ) (0.198662, 0.041312), point of zero charge (PZC) (5.2), pH levels (6, 7), contact times (10, 25 min), photocatalyst dosages (0.3, 0.05 g), dye concentrations (2, 10 µg/mL), and temperature effects (50°, 90°) on the adsorption and photocatalytic degradation of MG and MB, respectively. Photodegradation of both dyes followed pseudo-second order kinetics with R2 values of 0.9833 (MG) and 0.8875 (MB). The adsorption isotherms (Freundlich and Langmuir) for MG and MB dye were analyzed and the experimental data holds a good correlation with Freundlich isotherm. The sample application of Cu-MOF@Fe3O4 as a photocatalyst, has high efficiency, % photocatalysis (96.9 % MG, 99.4 % MB) with reusability (95–100 %) upto 10 cycles to photodegrade MG and MB dye in wastewater. To the best of our knowledge, this is the first report on the deployment of copper-based MOFs-doped with magnetite for the photocatalytic degradation of MG and MB dyes. [ABSTRACT FROM AUTHOR]

Inadequate wastewater treatment infrastructure is a substantial worldwide concern, with implications for both the environment and public health. Specifically, the discharge of industrial effluents containing organic pollutants such as dyes represents a significant challenge due to their hazardous characteristics. Among these dyes, Bromophenol Blue (BPB) and Malachite green (MG) are extensively utilized in the industrial sector, contributing to environmental deterioration. In the current study, ternary-magnetic-silicate–graphene oxide [Fe3O4@SiO2–GO] was synthesized using the co-precipitation method and applied for the treatment of wastewater containing BPB and MG dyes. The point of zero charge and surface area of the adsorbent was estimated to be 5.7 and 253.8 m2 g−1, respectively. Energy dispersive X-ray was performed and the presence of iron, silicon, carbon, and oxygen was confirmed. The XRD analysis of GO, Fe3O4, and ternary Fe3O4@SiO2–GO composites were also performed to confirm the crystallinity of the composite. The SEM analysis showed a rough morphology with sheet-like appearance. The ternary composite was then applied for the adsorption of BPB and MG dyes. The maximum adsorption capacity for BPB and MG was 97.35 mg/g and 92.63 mg/g at pH 3 and 5, respectively. The results of the kinetics analysis showed that the pseudo-second-order kinetics model best explained the adsorption data for MG dye while pseudo-first-order kinetics for the BPB dyes. While the data best fitted the Langmuir adsorption isotherm with R2 values of 0.994 and 0.998 for BPB and MG, respectively. These results demonstrate that Fe3O4@SiO2–GO serves as a promising adsorbent for the efficient removal of Bromophenol Blue (BPB) and Malachite Green (MG) from environmental water samples. Additionally, this adsorbent is environmentally friendly and chemically benign, and it can be reused efficiently for up to five cycles. [ABSTRACT FROM AUTHOR]

Inadequate wastewater treatment infrastructure is a major environmental and public health concern worldwide. Industrial effluents containing organic pollutants such as dyes constitute a severe challenge due to their toxicity. Malachite green (MG) and methylene blue (MB) are two organic dyes that are widely used in textiles but also damage the environment. Herein, we report the fabrication of bismuth ferrite-coated nickel/nickel oxide foam (BFCNF) heterojunction photocatalyst via the dip-coating approach. The point of zero charge and the estimated surface area of BFCNF was observed to be 7.5, and 213.19 m2 g−1, respectively. Energy dispersive X-ray (EDX) spectra revealed the presence of Ni, O, Bi, and Fe elements in the BFCNF. The scanning electron microscopy (SEM) analysis revealed that BFCNF has a granular coarse surface morphology. The XRD anslysis showed that the average-crystallite size for Ni/NiO, BFO, and BFCNF was found to be 28, 1.00, and 1.00 nm, respectively. The catalyst revealed outstanding performance while degrading 97 % of MG dye at pH 6, and 98 % MB dye at pH 5, under visible light irradiation of 20 min. The chemical oxygen demand (COD) studies were also performed for both of the dyes. Notably, a negligible COD was observed for both of the dyes after 80 min. In a real industrial wastewater treatment study, the catalyst almost degraded 99 % of both dyes. Further, the catalyst revealed excellent stability during four and seven consecutive recycles tests for MB and MG dyes, respectively. The degradation process follows pseudo-first-order kinetics with correlation coefficients (regression analysis, R2) of 0.949 and 0.974 for MG and MB, respectively. To the best of our knowledge, this is the first report on utilization of bismuth ferrite-coated nickel/nickel oxide foam based heterojunction photocatalyst. This work will trigger the development of highly efficient catalysts for efficient wastewater treatment. [ABSTRACT FROM AUTHOR]

Magnetic molecularly imprinted polymers (MMIPs) contain the predesigned specialized recognition capability that can be chosen to build credible functional materials, that are easy to handle and have a good degree of specificity. Hence, the given piece of work is intended to design a novel electrochemical sensor incorporating magnetite-based molecularly imprinted polymers. The building materials consisted of a cross-linker (EGDMA), reaction-initiator (AIBN), monomer (methylene succinic acid-MSA), and template molecule (Sunset Yellow-SY dye). MMIPs exhibited a diameter of 57 nm with an irregular shape due to the presence of cavities based on SEM analysis. XRD patterns exhibited crystallinity, as well as amorphous peaks that are attributed to polymeric and non-polymeric frameworks of MMIPs. The crystallite size of the MMIPs from XRD analysis was found to be 16.28 nm based on the Debye-Scherrer's equation. Meanwhile, the FTIR bands showed the synthesis of MMIPs using monomer and methylene succinic acid. The sorption data at the optimized operating conditions (pH 2, sorbent dosage 3 mg, time 18 min) showed the highest sorption capacity of 40 mg/g. The obtained data best fitted to the Langmuir sorption isotherm and followed the pseudo-second-order kinetics. The magneto-sensors were applied for ultrasensitive, rapid, and simple sensing of SY dye. The electrochemical experiments were run at the operating condition range of (scan rate 10–50 mV/s, tads 0–120 s, pH 5–9, potential range 1–1.5 V for CV and 1–1.3 V for SWAdASV). The linear range of detection was set to 1.51 × 10−6 M to 1.51 × 10−6 M posing LOD and LOQ values of 8.6242 × 10−5 M and 0.0002874 M, respectively. The regression analysis value for the calibration was found to be 0.950. Additionally, high adsorption efficiency, selectivity, reusability, and strong structural stability of the magneto-sensors showed potential use for SY detection in real samples. These characteristics make MMIPs a viable electrochemical substrate for the detection of chemical contaminants in the environment and in health-related products. [ABSTRACT FROM AUTHOR]

Research Summary: Health science firms have long product development horizons and need regulatory approval for market entry. In communicating with investors, they may use entrepreneurial orientation (EO) rhetoric to emphasize their strategic and behavioral commitment to product innovation and market entry. However, because EO rhetoric constitutes a soft‐information signal rather than evidence of substantive commitment, investors may suspect firm insiders using such rhetoric of impression management. The solution, we argue, is EO rhetoric sustained over time, which produces more reliable information for investors—in contrast to occasional increases in EO rhetoric, which invite skeptical scrutiny. Nevertheless, investors' potential concerns regarding changes in EO rhetoric can be mitigated by concurrent hard‐information signals that carry signaling costs or penalty costs for false signaling. Managerial Summary: Entrepreneurial orientation (EO) rhetoric can reduce information asymmetry between managers and investors. In strictly regulated contexts such as health science industries, using such rhetoric may be challenging. For firms embracing entrepreneurial strategies and behaviors, maintaining EO rhetoric over time is critical to overcoming skepticism that it is merely "cheap talk." For investors, this study also suggests that health science firms maintaining higher EO rhetoric over time deserve higher valuations, given the variety of benefits an EO can have for health science firms. If a health science firm aims to ramp up its EO rhetoric, managers should be aware that investors may interpret the increase as impression management and should confront this interpretation head‐on—for instance, by simultaneously increasing entry commitment or corporate social responsibility. [ABSTRACT FROM AUTHOR]

The present study reports the engineering of functionalized chitosan (CH)-based biosorbent material. Herein, a two-step reaction was performed to chemically modify the CH using 1,4-bis(3-aminopropyl) piperazine to incorporate nitrogen basic centers for cations sorption from the aqueous environment. The resultant functionalized chitosan-based sorbent material was designated as CH-ANP and characterized using various analytical techniques, including elemental analysis, Fourier-transform infrared spectroscopy (FTIR), 13C NMR (in solid-state), X-ray diffraction, and thermal analysis. Then, the newly engineered CH-ANP was employed for the removal of copper, lead, and cadmium in the aqueous medium. Langmuir sorption isotherm analysis revealed that the highest sorption abilities achieved were 2.82, 1.96, and 1.60 mmol g−1 for copper, cadmium, and lead, respectively. Linear and nonlinear regression methods were deployed on the sorption data to study the behavior of the Langmuir, the Freundlich, and the Temkin sorption isotherms. Among the four different forms, the Langmuir isotherm type 1 fit well to the experimental data as compared to the other models. It also showed the lowest values of error, and a higher correlation coefficient than the Freundlich and Temkin models; thus it was the best fit with the experimental data compared to the latter two models. In conclusion, the findings suggest that chemically modified novel materials with enhanced Lewis basic centers are useful and promising candidates for the sorption of various toxic cations in aqueous solution. [ABSTRACT FROM AUTHOR]

Herein, we report the development of chitosan (CH)-based bio-composite modified with acrylonitrile (AN) in the presence of carbon disulfide. The current work aimed to increase the Lewis basic centers on the polymeric backbone using single-step three-components (chitosan, carbon disulfide, and acrylonitrile) reaction. For a said purpose, the thiocarbamate moiety was attached to the pendant functional amine (NH2) of chitosan. Both the pristine CH and modified CH-AN bio-composites were first characterized using numerous analytical and imaging techniques, including 13C-NMR (solid-form), Fourier-transform infrared spectroscopy (FTIR), elemental investigation, thermogravimetric analysis, and scanning electron microscopy (SEM). Finally, the modified bio-composite (CH-AN) was deployed for the decontamination of cations from the aqueous media. The sorption ability of the CH-AN bio-composite was evaluated by applying it to lead and copper-containing aqueous solution. The chitosan-based CH-AN bio-composite exhibited greater sorption capacity for lead (2.54 mmol g−1) and copper (2.02 mmol g−1) than precursor chitosan from aqueous solution based on Langmuir sorption isotherm. The experimental findings fitted better to Langmuir model than Temkin and Freundlich isotherms using linear regression method. Different linearization of Langmuir model showed different error functions and isothermal parameters. The nonlinear regression analysis showed lower values of error functions as compared with linear regression analysis. The chitosan with thiocarbamate group is an outstanding material for the decontamination of toxic elements from the aqueous environment. [ABSTRACT FROM AUTHOR]

Wastewater containing dyes is considered as the top-priority pollutant when discharged into the environment. Herein, we report for the applicability of 254 nm ultraviolet light and electrochemical process using a titanium ruthenium oxide anode for the degradation of Allura red and erythrosine dyes. During the photolytic process, 95% of Allura red dye (50 ppm) was removed after 1 h at pH 12 and 35 °C, whereas 90% color removal of erythrosine dye (50 ppm) was achieved after 6 h of treatment at pH 6.0 and 30 °C. On the other hand, 99.60% of Allura red dye (200 ppm) was removed within 5 min by the electrochemical process applying a current density (5 mA cm -2 ) at pH 5.0 and 0.1 mol L -1 sodium chloride (NaCl) electrolytic medium. Similarly, 99.61% of erythrosine dye (50 ppm) degradation was achieved after 10 min at a current density of 8 mA cm -2 , pH 6.0, and 0.1 mol L -1 of NaCl electrolyte. The minimum energy consumption value for Allura red and erythrosine dyes (0.196 and 0.941 kWh m -3 , respectively) was calculated at optimum current densities of 5 and 8 mA cm -2 . The results demonstrated that the electrochemical process is more efficient at removing dyes in a shorter time than the photolytic process since it generates powerful oxidants like the chlorine molecule, hypochlorous acid, and hypochlorite on the surface of the anode and initiates a chain reaction to oxidize the dyes molecules.