In the present work, a polymer inclusion membrane (PIM) using an amphiphilic molecule Tween 20 (TW20) as the carrier was developed and characterized to hinder environmental contamination caused by norfloxacin (NRF), an antibiotic widely used in veterinary and human medicines. Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) coupled with energy X-ray dispersion spectroscopy (EDS) were used to reveal the composition, porosity, and morphology of the elaborated membrane. In order to measure the performance of the as-developed membrane, the influences of NRF initial concentration (C₀ = 0.04 mol L⁻¹, 0.02 mol L⁻¹, 0.01 mol L⁻¹, and 0.005 mol L⁻¹), pH (2.6, 4.5, and 10.5), and temperature (T = 298 K, 303 K, and 305 K) were investigated. The evolution of macroscopic (permeability (P) and initial flux (J₀)), microscopic (association constant (Kₐₛₛ) and apparent diffusion coefficient (D*)), and activation parameters (activation energy (Eₐ), enthalpy (∆H≠ₐₛₛ), and entropy (∆S≠)) was analyzed. It was found that TW20 was an effective agent for the extraction and recovery of different forms of NRF, especially the zwitterion form appeared at pH = 4.5. On the other hand, for the biologically active NRF compound, the mechanisms of the studied processes were controlled by the kinetic aspect rather than the energetic counterpart. Graphical abstract

Considering the time-varying, uncertain and non-linear properties of the wastewater treatment process (WWTPs), a novel multi-kernel relevance vector machine (MRVM) soft sensor based on time difference (TD) is proposed to predict the quality-relevant but difficult-to-measure variable. Firstly, a novel dimension reduction technique is introduced to reduce data dimension and model complexity. Secondly, the parameters of the kernel model are optimized by the intelligent optimization algorithm (PSO). Besides, the TD strategy is introduced to enhance the robustness of MRVM when exposing to dynamic environments. Finally, the proposed model was assessed through two simulation studies and a real WWTP with the results demonstrating the effectiveness of the proposed model. Graphical abstract Framework of Lasso-TD-MRVM soft sensor model

Due to changes in global climate and local hydrological variability, land–water interactions are considered the prevailing processes underpinning aquatic ecology. Periodic meteorological conditions could have significant effect upon freshwater plankton communities by modifying the relative influences of biotic and abiotic structuring factors. However, the influence of unusual meteorological events, such as the El-Niño Southern Oscillation cycles, and advection on zooplankton communities of tropical shallow lakes and reservoirs are not fully understood. The present study, therefore, aimed to explore the relationship between hydrological factors and zooplankton community structure in Koka Reservoir, Ethiopia. Field measurements and collection of water samples and zooplankton were performed at monthly intervals from January to August 2016 at three sampling sites along a stretch of the reservoir from the river mouth to the center and the outlet (dam). The results showed post-El-Niño hydrological events (i.e., elevated riverine runoff and higher levels of turbidity) and associated advective losses can disrupt zooplankton community structure at the river mouth site, particularly during the rainy period. The results suggest that integrated watershed management activities are important aquatic resource management options in small- and medium-sized lakes and reservoirs.

Many studies have demonstrated the effectiveness of algicidal compounds produced by macrophytes against microalgae. The aim of this study was to assess the algicidal activity of seven Moroccan macrophyte ethyl acetate extracts (MEA) to control harmful algal blooms (HABs). The response and sensitivity of prokaryotic toxic cyanobacteria (Microcystis aeruginosa) and eukaryotic microalgae (Chlorella sp.) were highlighted. The algicidal effect of MEA extracts against the two microalgae was assessed using both the paper disc diffusion and microdilution methods. This last was used in order to evaluate the minimum inhibitory concentrations (MIC) and minimum algicidal concentrations (MAC). Results showed that the growth of both microalgae was significantly inhibited by all MEA extracts. Myriophyllum spicatum organic extract shows the highest growth inhibition activity against M. aeruginosa (35.33 ± 1.53) and Chlorella sp. (30.33 ± 1.15 mm). This stronger inhibitory activity was confirmed by the low MIC (6.25, 12.5 mg/L) and MAC (6.25, 12.5 mg/L) values. Furthermore, results showed different sensitivity between the prokaryotic and eukaryotic microalgae into MEA extracts. Based on the MIC and MAC values, we can distinguish two groups of plants. The first one, including M. spicatum, Ranunculus aquatilis, and Enteromorpha sp., can be considered as a preferable anti-prokaryotic group with a stronger inhibitory activity on M. aeruginosa growth. The second group, constituted by Potamogeton natans, Nasturtium officinale, Elodea sp., and Ceratophyllum sp., has a preferable and stronger inhibitory effect against eukaryotic algae (Chlorella sp.). Overall the results reveal the potential algicidal activity of macrophytes and suggested that MEA extracts could play an important role in biocontrol of HABs.

The present study proposes the synthesis and characterization of graphene oxide (GO) and its application in the adsorption of the antibiotic cephalexin (CFX) in aqueous solution. The characterization of graphene oxide was obtained by scanning electron microscopy (SEM), transmission electron microscopy (TEM), and zeta potential. The influence of pH on the batch adsorption process was investigated by analysing adsorption equilibrium isotherms and adsorption kinetics. The images obtained by SEM and TEM presented the typical morphology attributed to GO sheets. The kinetic adsorption tests showed that equilibrium was reached in 420 min, and an adsorption capacity of 164 mg g⁻¹ was obtained. The models that best fit the experimental data were pseudo-second as well as the Langmuir isotherm. Therefore, GO was effective for removing the CFX antibiotic from aqueous solution by using a batch adsorption process.

This is the first attempt to explore the impact of environmental regulation intensity deviation on inclusive growth. An analysis framework in which the deviation between actual intensity and optimal intensity affects inclusive growth is constructed. Based on this analytical framework, this study uses panel data from 281 prefecture-level cities in China during the period 2004–2016 to investigate environmental regulation intensity deviation, as well as the feature, heterogeneity, and mechanisms of environmental regulation intensity deviation affecting inclusive growth. The empirical findings show that (i) environmental regulation has an inverted U-shaped effect on inclusive growth, but the actual intensity of environmental regulation in China is lower than the optimal intensity, which makes it difficult to give full play to its incentive role on inclusive growth; (ii) further grouping tests show that environmental regulation intensity deviation will inhibit inclusive growth within regions but promote inclusive growth between regions due to the difference in deviation; (iii) technological innovation, industrial transformation, and foreign investment have a partial mediating effect, which may be important mechanisms for environmental regulation intensity deviation to restrain inclusive growth; and (iv) the robustness test of informal environmental regulation supports the findings of formal environmental regulation and finds that the deviation of informal environmental regulation is more severe than that of formal environmental regulation. The empirical findings therefore suggest that policymakers should scientifically improve the environmental regulation intensity and optimize the environmental regulatory structure.

In order to explore the high value-added utilization of flyash adsorption in regenerating waste lubricating oil, the main factors related to the flyash adsorption was investigated by the single-factor tests, and then the optimum process conditions for flyash adsorption was obtained by means of the orthogonal experiments, and in terms of several indexes, such as kinematic viscosity (40 °C), acid number, mechanical impurity and moisture, the combined process of flyash adsorption/solvent extraction was discussed and finally compared with previous studies. The experimental results prove that flyash has a good effect in adsorbing waste lubricating oil, and the solvent extraction-flyash adsorption process has a better effect in the regeneration of waste lubricating oil than the flyash adsorption-solvent extraction process.

Rapid urban growth and high population density have become a problem for urban water resources, especially in developing countries. In general, the pollution of rivers and degradation of ecosystems are the result of both management failures and lack of sewage treatment. River restoration appears as a solution to improve this scenario, but it is common for there to be an absence of a systemic vision in these projects. Thus, this work analysed one of these projects as an initial approach to create coherent (qualitative) shared perspectives on the same problem. This project was developed in a Brazilian university territory in response to a Public Civil Action. Rivers within the university surroundings are degraded due to sewage disposal and wastewater pollution from external and internal sources within the university, but the programme actions contemplate only interventions within the perimeter of the university while excluding the other parts of its watershed. We analyse this problem under a Systems Thinking approach by using causal loop diagrams, being clear that ecosystems cannot be reduced to territorial limits only. The systemic map shows many actions that contribute to the water quality degradation, with emphasis on illegal dumping of wastewater (sewage) and land use change in the upstream areas prior to the university. Point measures are palliative and do not guarantee the quality of river water. Regulation of impervious surfaces and correct disposal of wastewater can improve the current panorama, but greater integration between stakeholders and other key actors is required.

In the present study, PANI-TiO₂ nanocomposites have been used in suspended and immobilized form for photocatalytic degradation of Acid Yellow 17 (AY-17) dye under visible light. PANI-TiO₂ nanocomposites were immobilized in polystyrene cubes to form PANI-TiO₂ @ polystyrene cubes. The nanocomposites were found to be visible light active both in suspended and immobilized form. PANI-TiO₂ nanocomposite with 13% TiO₂ loading was found to be the optimum in terms of maximum degradation of AY-17. The efficiency of floating bed photoreactor (FBR) operated in liquid recycle mode using PANI-TiO₂ @ polystyrene cubes was studied. In this reactor, around 89% degradation of 1 L of AY-17 with an initial concentration of 10 mg/L could be achieved with 2.83 g/L per pass of immobilized catalyst. The FBR operated with PANI-TiO₂ @ polystyrene cubes has exhibited good performance as a photocatalytic reactor and may be recommended over other conventional photo reactors for treatment of wastewater contaminated with synthetic dyes. The kinetics of degradation of AY-17 by photocatalysis under visible light with suspended PANI-TiO₂ and PANI-TiO₂ @ polystyrene cubes followed first-order kinetics. The values of apparent kinetic parameter for degradation by immobilized photocatalysts are lower than the corresponding kinetic parameter for suspended photocatalysts. It confirms the existence of diffusional limitations in photocatalysis by PANI-TiO₂ @polystyrene cubes.

Phytoplankton-derived particulate matter (PPM) is the active component of the solid particles in eutrophic shallow lakes. To date, understanding of the degradation characteristics of PPM and the effect of degradation products on nutrient cycling in water are limited. In this study, field observations and simulation experiments were carried out to elaborate the nutrient transformation during phytoplankton-derived particulate matter deposition in the cyanobacterial blooming area of Lake Taihu. Results showed that the deposition of the PPM was strongly facilitated by the cyanobacterial bloom and the sediment resuspension. The main variation characteristics of phosphorus (P) species in PPM are shown in the increase of Ortho-P and the decrease of biodegradable phosphorus (Poly-P, DNA-P) during the deposition of PPM. The degradation of the PPM resulted in the release of dissolved nitrogen (N) and P to the water body. The conversion of easily degradable particulate N and P in the PPM to ammonium nitrogen (NH₃-N) and soluble reactive phosphorus were believed to be responsible for this phenomenon. The cycling of nutrients and the cyanobacterial bloom status might therefore be altered because of the deposition and degradation of PPM. More considerations should be given on this process in future works.