Phytophthora nicotianae is currently considered one of the most devastating oomycete plant pathogens, and its control frequently relies solely on the use of systemic fungicides. There is an urgent need to find environment-friendly control techniques. This study examined the chemical composition, inhibitory activity, and possible modes of action of the essential oil of Chrysanthemum indicum L. (EOC) flower heads against P. nicotianae. The EOC was obtained using hydrodistillation at a 0.15% yielded. It inhibited mycelial growth and spore germination of P. nicotianae at a minimum inhibitory concentration (MIC) of 200 μL/L, and exhibited fumigation effects (92.68% inhibition at 157.48 μL/L). Marked deformation of P. nicotianae mycelia included deformed tip enlargement, shrinkage, and rupture. Further, 55 and 47 compounds were identified using gas chromatography-mass spectrometry (GC-MS) and headspace solid-phase microextraction (HS-SPME) GC-MS analyses, representing 88.2% and 98.91% of the total EOC, respectively. Monoterpenes (25.77%) and sesquiterpenes (54.14%) were the major components identified using GC-MS, whereas monoterpenes were the main constituents in the HS-SPME GC-MS analysis. The higher proportions of sesquiterpenes and monoterpenes could be responsible for the inhibitory activity of EOC, which increased mycelia membrane permeability and the content of mycelial malondialdehyde (MDA) in a dose-dependent manner. Cell death also occurred. Thus, destruction of the cell wall and membrane might be two modes of action of EOC. Our results would be useful for the development of a new plant source of fungicide for P. nicotianae-induced disease.

This study analyzed the performance of organophilic clays obtained from the chemical modification of sodium bentonite clay when applied to the adsorption of herbicide 2,4-dichlorophenoxyacetic acid (2,4-D). Kinetic curves and equilibrium isotherms were obtained in order to determine time and adsorption capacity of the material, as well as understand the mechanisms involved in this phenomenon. The results showed that the most predictive kinetic model for experimental data was of pseudo-second order (R² > 0.98), and that external mass transfer is the dominant factor in the time of operation. Isotherms were obtained at temperatures of 298, 308, and 318 K, under which the Dubinin-Radushkevich model was shown to have a good fit to data (R² > 0.96), according to mathematical adjustments. The maximum adsorption capacity obtained experimentally was 50.36 mg g⁻¹, found at a temperature of 298 K, being higher or compatible with other materials reported in the literature. With help of the thermodynamic studies on the process, it was observed that the adsorption of 2,4-D in organophilic clays refers to a spontaneous (ΔG°ₐdₛ < 0), exothermal (ΔH°ₐdₛ = − 9.99 kJ mol⁻¹) process of physical nature. Lastly, it was observed that the adsorbent can be easily regenerated when subjected to eluents such as mixtures containing fractions of ethanol/water (desorption = 95%).

In recent decades, climate change and environmental pollution have been at the center of global environmental debates. Nowadays, researchers have turned their attention to the linkage between real output and environmental quality and test the environmental Kuznets curve. Majority of the studies focus on a single pollutant aspect and measure the deterioration of the environment through carbon emission (CO₂) only. In contrary, the current study uses a comprehensive proxy, ecological footprint, to measure the environmental quality of the sixteen Central and Eastern European Countries (CEECs). The aim of this paper is to discover the impact of financial development, economic growth, and energy consumption (renewable and non-renewable) on the environment. In addition, for the first time, the current study includes biocapacity and human capital in the growth–energy–environment nexus in the case of CEECs. In doing so, we used annual data of sixteen CEE countries in perspective of the One Belt One Road (OBOR) initiative and cover the period of 1991–2014. For reliable findings, this study focuses on second-generation econometric approaches to check stationarity, cross-sectional dependency, and co-integration among the model parameters. The long-run estimations of the “Dynamic Seemingly Unrelated-co-integration Regression” (DSUR) signify that the effect of economic growth on ecological footprint is not stable and validate N-shaped relationship for cubic functional form between per capita income and ecological footprint (environmental quality). Empirical evidence divulges that financial development and energy use significantly contribute to environmental degradation while renewable energy improves environmental quality by declining ecological footprint significantly. Moreover, the significant effects of biocapacity and human capital are positive and negative on the ecological footprint, respectively. In robustness check through the “Feasible Generalized Least Square” (FGLS) and “Generalized Method of Moment” (GMM) models, we found consistent result. Lastly, the “Dumitrescu-Hurlin (D-H) Panel Causality Test” demonstrates that two-way causal relationship exists between EF and GDP, EF and FD, EF and EU, EF and BC, and EF and HC, while one-way causality is running from RE to EF. This study puts the present scenario of CEE economies in front of the policymakers and suggests that they should consider the vital role of renewable energy and human capital to get sustainability.

Bioelectrochemical systems (BESs) including microbial electrolysis cells (MECs) and microbial fuel cells (MFCs) are promising for hexavalent chromium [Cr(VI)] reduction and total chromium (Cr) removal from wastewater. This study assessed the performance of simple, inexpensive, and continuous flow BESs with neither cathode catalyst nor proton exchange membrane for Cr(VI) reduction and total Cr removal. The effect of bioreactor configuration and wastewater feed mode on the performance of the BESs was investigated. Biological Cr(VI) reduction in the MEC followed a first-order kinetics with a rate constant of 0.103 d⁻¹, significantly higher than that of the control (0.033 d⁻¹). For comparison, the first-order reduction rate constants in the MFCs with the Cr(VI) fed to the anodic and the cathodic zones were 0.072 and 0.064 d⁻¹, respectively. The BESs improved total Cr removal through coprecipitating Cr(III) and phosphors as evidenced from the scanning electron microscopy energy-dispersive X-ray spectroscopy analysis. The total Cr removal efficiencies in the control, MFCs, and MEC were 26.1%, 56.7%, and 66.2%, respectively. Only 25.1% to 26.7% of total Cr was present intracellularly in the BESs (both MFCs and MEC), whereas 31.8% ± 1.4% and 38.0% ± 0.9% of total Cr in the anodic and cathodic zones of the control were present intracellularly. Overall, the BESs demonstrated a great potential to reduce Cr(VI) and remove total Cr with the MEC having the fastest Cr(VI) reduction and most efficient total Cr removal. Furthermore, the BESs significantly reduced the intracellular total Cr content.

Graphene oxide (GO) was synthetized from graphite oxidation via the modified Hummers method. Afterwards, the GO was functionalized with diethylenetriamine (DETA) and FeCl₃ to obtain the novel amino-iron oxide functionalized graphene (GO-NH₂-Fe₃O₄). FTIR, XRD, SEM with EDX, and Raman spectroscopy were performed to characterize both GO and GO-NH₂-Fe₃O₄. The GO-NH₂-Fe₃O₄ was then evaluated as adsorbent of the cationic dye Methylene Blue (MB); analysis of the point of zero net charge (pHPZC) and pH effect showed that the GO-NH₂-Fe₃O₄ pHPZC was 8.2; hence, the MB adsorption was higher at pH 12.0. Adsorption kinetics studies indicated that the system reached the equilibrium state after 5 min, with adsorption capacity at equilibrium (qₑ) and kinetic constant (kS) of 966.39 mg g⁻¹ and 3.17∙10⁻² g mg⁻¹ min⁻¹, respectively; moreover, the pseudo-second-order model was better fitted to the experimental data. Equilibrium studies showed maximum adsorption capacity of 1047.81 mg g⁻¹; furthermore, Langmuir isotherm better fitted the adsorption. Recycling experiments showed that the GO-NH₂-Fe₃O₄ maintained the MB removal rate above 95% after 10 cycles. All the results showed sorbent high adsorption capacity and outstanding regeneration capability and evidenced the employment of novel GO-NH₂-Fe₃O₄ as a profitable adsorbent of textile dyes.

Yeast biomass from ethanol industry (YB) was evaluated as a biosorbent to 17α-ethinylestradiol (EE) alone and along with estrone (EST). This material is rich in sorption sites and has a good cost-benefit ratio, since it is an industrial residue largely produced (around 30 g for each liter of ethanol). A 2ᵏ-factorial design was carried out to evaluate the sorption capacity of YB for EE considering the variables pH, biosorbent dose (BD), and ionic strength (IS), at two hormone concentration (HC) levels. The best conditions assessed for individual EE adsorption (pH = 10, IS = 0.1 mol/L, and BD = 0.5 mg/L) were also established for adsorption carried out in the presence of EST. Individuals EE and EST experimental sorption capacities (SCₑₓₚ) were, respectively, 24.50 ± 0.07 and 0.80 ± 0.07 mg/g, fairly similar to Qₘₐₓ (EE, 21.41 ± 1.27 mg/g; EST, 0.93 ± 0.075 mg/g) from Langmuir model. The Freundlich model best fitted the experimental data for EE adsorption (r² = 0.9925; χ² = 0.5575). The study carried out in the presence of EST showed an associative/competitive sorption process between EE and EST, which may be explained by their similar chemical structures and organic carbon-water partition coefficients Kₒc.

Vegetable oils are found suitable alternate of diesel fuel as per the results of short-run studies. Long-run studies with vegetable oil as a fuel pointed out the problems related to wear and maintenance of the engine. A single cylinder, variable compression ratio diesel engine was tested for 512 h (32 cycles of 16 h per day) to investigate longevity implications of fueling Thumba vegetable oil. Results of the study revealed that a very little damage was observed over the running surface of the cylinder liner, piston rings, valves, and valve seats. Wear in the piston outer diameter was observed to be 13 to 30 microns. Cylinder wear was about 80 microns. The closed gap in the oil piston ring increased up to 200 microns. Heavy carbon deposition was found on different internal parts of the engine, which indicates poor combustion of fuel. Amount of copper (66 mg/kg) and silicon (112 mg/kg) dissolved in the lubricating oil was found more than permissible limits (Cu 50 mg/kg, Si 25 mg/kg), after 450-h engine test run. But all the dissolve materials remain in allowable limits when the durability test conducted with diesel. Smoke, CO, HC, and NOX emissions were found to increase initially then decrease in the further engine running hours. But these emissions were found inferior to the engine emissions fueled with diesel in all the running hours. CO2 emissions were found superior throughout the test with the preheated T20 Thumba oil blend than diesel. The maximum reduction in the viscosity of the lubricating oil, during endurance testing, was found 60 centipoises but it was found 25 centipoises when the test conducted with diesel.

During the past few decades, the Yangtze River basin has undergone massive anthropogenic change. In order to evaluate the impacts of human interventions on sediment n-alkanes of lakes across this region, the aliphatic hydrocarbon fractions of 19 surface sediment samples collected from lakes along the middle reaches of the Yangtze River (MYR) were analyzed using gas chromatography–mass spectrometry. The n-alkanes extracted from the sediments contained a homologous series from C15 to C34, with a notable predominance of odd carbon compounds except for sediments from the more intensively industrialized Lake Daye, in which > C21 n-alkanes showed no odd/even predominance, and carbon preference index (CPI) approached unity. Abundance values of middle-chain (C21, C23, and C25) and long-chain (C27, C29, C31, and C33) n-alkanes in Lake Daye were approximately 4 to 3 times greater than the average for other lakes, reaching 272.4 and 486.3 μg/g TOC, respectively, in the study. Short-chain n-alkanes (C15, C17, and C19) in the sediments varied in abundance from 10.0 to 76.2 μg/g TOC across the study and showed a moderate correlation with total phosphorus (TP) concentrations in the overlying water. The results indicated anthropogenic eutrophication enhanced the accumulation of short-chain n-alkanes in sediments because the primary producers in which they are synthesized are highly susceptible to nutrient forcing. Middle-chain n-alkane abundances were less affected by eutrophication and generally enriched in macrophyte lakes, while long-chain n-alkanes tend to be low in sediments from more eutrophic water. In the case of Lake Daye, direct discharges of petroleum products from heavy industry have introduced quantities of petroleum n-alkanes (> C21), far exceeding the amounts of biogenic input, and the sediment > C21 n-alkanes detected in this study showed typical characteristics of petroleum source. In other lakes, inputs of petroleum products from surface runoff of vehicle/traffic emissions associated with urbanization and economic growth contributed comparatively few n-alkanes to sediments, resulting in declines in CPI for > C21 n-alkanes, most obviously in Lakes Huanggai, Donghu, and Futou. Calculated CPI values suggest that a major proportion of the n-alkanes present in these lakes are derived from biogenic input. The results of this study provided evidences that n-alkane profiles of lake sediments respond sensitively to human-induced eutrophication and different sources of petroleum pollution.

Current economic policy planning places much emphasis on balancing development and environmental protection. Hence, it is important to determine the drivers of environment pollution from the theoretical, scientific, and policymaking aspects in the context of continuous economic growth. This paper investigates the factors affecting per capita CO₂ emissions in 30 provinces in Iran from 2009 to 2014 with emphasis on spatial spillover effects using the Spatial Durbin Model. The findings show that per capita CO₂ emissions are positively and significantly affected by per capita GDP, industrialization, and urbanization but negatively affected by changes in population. The results of the spatial section of the model indicate that both the more and the less-polluted provinces tend to cluster together, indicating positive spatial dependence for CO₂ emissions in the provinces. Also, the spatial spillover of per capita GDP and the growth of urbanization have a negative and significant effect on per capita CO₂ emissions in the provinces, while the spatial effect of changes in population is significant but positive. In other words, the economic development and rise in urbanization in one province are the results of changes in pollution levels in neighboring provinces.

ZnAl-layered double hydroxide-loaded banana straw biochar (ZnAl-LDH-BSB) was prepared via the hydrothermal method, and the efficient phosphorus removal agent ZnAl-LDO-BSB was obtained by calcination at 500 °C. Based on the ZnAl-LDO-BSB adsorption characteristics, the adsorption mechanism was evaluated via TG/DTA, FTIR, XRD, SEM, HRTEM, and other characterization methods. The results showed that the ZnAl-LDO-BSB assembled into microspheres with typical hexagonal lamellar structures and presented good thermal stability. The adsorption of total phosphate (TP) by ZnAl-LDO-BSB conforms to the Langmuir model, and the theoretical maximum adsorption capacity is 185.19 mg g⁻¹. The adsorption kinetics were in accordance with the second-order kinetic model, and the anion influence on TP adsorption followed the order CO₃²⁻ > SO₄²⁻ > NO₃⁻. The combination of zeta potential measurements with the FTIR, XRD, SEM, HRTEM, and XPS results suggested that ZnAl-LDO-BSB adsorbs TP mainly by electrostatic adsorption, surface coordination, and anion intercalation. Graphical abstract