In the modern era of globalization, the rapid increase in information and telecommunication technologies (ICTs) contributes in various sectors of an economy; however, the environmental consequences of ICTs cannot be ignored. Therefore, the study investigates the nexus between ICTs, economic growth, financial development, and environmental quality in emerging economies. The novel feature of the study is that the interaction term of ICT is introduced with economic growth and financial development. The empirical findings of the study are based on panel mean group (MG) and augmented mean group (AMG) estimation methods from 1990 to 2015. The following empirical results are established: first the ICTs significantly affect CO₂ emissions. Second, the moderating effect of ICT and financial development stimulate the level of CO₂ emissions. Third, economic growth contributes CO₂ emission; however, the interaction between ICT and GDP mitigates the level of pollution. Policy thresholds with the R&D in ICT sector are required to mitigate the level of CO₂ emission. Introduction of green ICTs projects in the financial sector is a better choice to improve the energy efficiency.

This study is the first attempt to investigate the relationship between CO₂ emissions, energy consumption, and economic growth at a state level, for the 50 US states, through a time-varying causality approach using annual data over the periods 1960–2010. The time-varying causality test facilitates the better understanding of the causal relationship between the covariates owing to the fact that it might identify causalities when the time-constant hypothesis is rejected. Our findings indicate the existence of a time-varying causality at the state level. Specifically, the results probe eight bidirectional time-varying causalities between energy consumption and CO₂ emission, six cases of two-way time-varying causalities between economic growth and energy consumption, and five bidirectional time-varying causalities between economic growth and CO₂ emission. Moreover, we examine the traditional environmental Kuznets curve hypothesis for the states. Notably, our results do not endorse the validity of the EKC, albeit the majority of states support an inverted N-shaped relationship. Lastly, we can identify multiple policy implications based on the empirical results.

Here, we successfully developed a template-free way to fabricate hierarchically porous magnesium oxide (MgO) and carefully investigated the adsorption behavior for phosphate and methyl orange (MO). The average pore size and the percentage porosity decreased with the increase in the feeding ratio of Mg²⁺/NH₃. Among the three samples, MgO-25 shows the highest surface area of 63 m² g⁻¹ determined by the mercury intrusion method, and MgO-50 exhibits the highest BET surface area of 121 m² g⁻¹. For all the MgO samples, the adsorption process follows the pseudo second-order and Langmuir isotherm for phosphate, while pseudo second-order and the Freundlich isotherm for MO. Among the investigated samples, MgO-25 shows the most maximum removal capacity of 478.5 mg g⁻¹ for phosphate and the highest removal capacity of 4483.9 mg g⁻¹ for MO. This study compromises a low-cost and convenient dual function material for excellent water remediation of multiple industries.

The hydroxyl radical, as the most important oxidant, controls the removal of some volatile organic compounds (VOCs) in the atmosphere. In this work, the atmospheric oxidation processes of acrylic acid by OH radical have been investigated by density functional theory (DFT). The energetic routes of the reaction of CH₂CHCOOH with OH radical have been calculated accurately at the CCSD(T)/cc-pVTZ//M06-2X/6-311++G(d,p) level. It is implicated that the oxidation has five elementary reaction pathways mostly hinging on how hydroxyl radical approaches to the carbon skeleton of acrylic acid. The atmospheric degradation mechanisms of the CH₂CHCOOH by OH radical are the formation of reactive intermediates IM1 and IM2. Meanwhile, the further oxidation mechanisms of IM1 and IM2 by O₃ and NO are also investigated. The rate coefficients have been computed using tight transition state theory of the variflex code. The calculated rate coefficient is 2.3 × 10⁻¹¹ cm³ molecule⁻¹ s⁻¹ at standard pressure and 298 K, which is very close to the laboratory data (1.75 ± 0.47 × 10⁻¹¹ cm³ molecule⁻¹ s⁻¹). Moreover, the atmospheric lifetime of acrylic acid is about 6 h at 298 K and 1 atm, implying that the fast sinks of acrylic acid by hydroxyl radical.

Identification of hot spots of land degradation is strongly related with the selection of soil tracers for sediment pathways. This research proposes the complementary and integrated application of two analytical techniques to select the most suitable fingerprint tracers for identifying the main sources of sediments in an agricultural catchment located in Central Argentina with erosive loess soils. Diffuse reflectance Fourier transformed in the mid-infrared range (DRIFT-MIR) spectroscopy and energy-dispersive X-ray fluorescence (EDXRF) were used for a suitable fingerprint selection. For using DRIFT-MIR spectroscopy as fingerprinting technique, calibration through quantitative parameters is needed to link and correlate DRIFT-MIR spectra with soil tracers. EDXRF was used in this context for determining the concentrations of geochemical elements in soil samples. The selected tracers were confirmed using two artificial mixtures composed of known proportions of soil collected in different sites with distinctive soil uses. These fingerprint elements were used as parameters to build a predictive model with the whole set of DRIFT-MIR spectra. Fingerprint elements such as phosphorus, iron, calcium, barium, and titanium were identified for obtaining a suitable reconstruction of the source proportions in the artificial mixtures. Mid-infrared spectra produced successful prediction models (R² = 0.91) for Fe content and moderate useful prediction (R² = 0.72) for Ti content. For Ca, P, and Ba, the R² were 0.44, 0.58, and 0.59 respectively.

A spent nuclear fuel (SNF) pool is a key facility for safe management of nuclear waste, where spent nuclear fuel rods are stored in a water pool. The spent fuel rods carry a significant amount of radioactivity; they are either recycled or stored for further processing. Pool water acts as a heat sink as well as a shield against the radiation present in spent/burned fuel rods. The water used in these pools is filtered by an ultra-filtration process which makes certain the purity of water. As the life span of these pools is approximately 20 to 40 years, the maintenance of pure water is a big challenge. A number of researchers have shown the presence of bacterial communities in this ultrapure water. The bacterial types present in SNF pool water is of increasing interest for their potential bioremediation applications for radioactive waste. The present study showed the isolation of six bacterial species in the SNF pool water samples, which had significant radio-tolerance (D₁₀ value 248 Gy to 2 kGy) and also biofilm-forming capabilities. These strains were also investigated for their heavy metal removal capacity. Maximum biofilm-mediated heavy metal (Co and Ni) removal (up to 3.8 μg/mg of biomass) was observed by three isolates (FPB1, FPB4, and FPB6). The ability of these bacterial isolates to survive in radioactive environments can be of great interest for remediation of radioactive contaminants.

In the present study, an attempt was made to develop a proof of concept for the detection of nitroaromatic explosive derivatives through the photoluminescence (PL) quenching process using functionalized diatom frustules as a sensing platform. The diatom frustules are composed of nanostructured, highly porous biogenic silica material and emit strong, visible blue PL upon UV excitation. PL-active biosilica was isolated from the marine diatom Nitzschia sp. and was amine-functionalized to develop a sensing platform. Functionalized diatom frustules were further characterized using field emission scanning electron microscope and a series of spectroscopic methods. When nitroaromatic compounds were bound to the functionalized diatom frustules biosilica, the PL intensity from the functionalized biosilica was partially quenched due to the electrophilic nature of the nitro (–NO) groups. The quenching process confirmed the Meisenheimer complex formation and was investigated by using Fourier transform infrared spectroscopy and time-resolved photoluminescence studies. The developed platform was further evaluated for its sensitivity and specificity, and the limit of detection (LOD) of the assay was determined as 1 μM for a series of nitroaromatic explosive compounds. In conclusion, the developed sensing platform will have great utility in the development of on-site detection platforms for sensitive detection of warfare explosive nitroaromatic compounds from the environment.

The construction of the Three Gorges Reservoir (TGR) as well as the development of local industry and agriculture not only had tremendous impacts on the environment but also affected human health. Although water, soil, and air in the TGR have been well studied for environmental risk assessment, very little information is available on benthic sediments and microorganisms. In this study, sedimentary samples were collected along the main stream of the TGR to examine microbial phospholipid fatty acids (PLFA) and relevant variables (e.g., nutrients and heavy metals) after the full operation of the TGR. The results showed that there were prominent trends (increase or decrease) of sedimentary PLFAs and properties from downstream to upstream. Bacteria-specific PLFA decreased toward the dam, while fungi-specific PLFA did not show any significant trend. The PLFA ratio of fungi to bacteria (F/B) increased along the mainstream. The total PLFA concentration, which represents the microbial biomass, decreased significantly toward the dam. Upstream and downstream sampling points were clearly distinguished by PLFA ordination in the redundancy analysis (RDA). That finding showed microbial PLFAs to have an obvious distribution pattern (increase or decrease) in the TGR. The PLFA distribution was markedly controlled by nutrients and heavy metals, but nutrients were more important. Moreover, among nutrients, Bio-P, NH₄⁺-N, NO₃⁻-N, and DOC were more important than TP, TN, TOC, and pH in controlling PLFA distribution. For heavy metals, Tl, V, Mo, and Ni were more important than Zn, Cu, Cd, and Pb. These findings suggested that Tl, V, Mo, and Ni should not be ignored to guard against their pollution in the TGR, and we should pay attention to them and make them our first priority. This study highlighted that the construction of the TGR changed riverine environments and altered microbial communities in sediments by affecting sedimentary properties. It is a reminder that the microbial ecology of sediment as an indicator should be considered in assessing the eco-risk of the TGR.

The potential of lipid accumulation by oleaginous yeast Cryptococcus vishniaccii grown on amaranth seed aqueous extract (AAE) media was assessed. Maximum cell biomass productivity of 104 mg/L/h, lipid productivity of 54 mg/L/h, and lipid content of 52.31% were recorded on AAE when carbon to nitrogen (C:N) ratio increased from 134 to 147 after removal of ammonia nitrogen. The lipid droplet (LD) size (2.32 ± 0.38 μm) was visualized by fluorescence microscopy using Nile red stain indicating maximum accumulated triacylglycerol (TAG) at C:N 147. Fatty acid methyl ester (FAME) profile obtained after transesterification of extracted lipid revealed the presence of palmitic acid (16:0), palmitoleic acid (16:1), stearic acid (18:0), oleic acid (18:1), and linoleic acid (18:2). Data showed the presence of high monounsaturated fatty acid (MUFA) content (68.17%) depicting improved winter operating conditions of biodiesel. Various quality parameters of biodiesel were evaluated and compared to the American and European biodiesel standards specifications. Based on the lipid productivity, distribution of fatty acids, and evaluated properties obtained; the lipid accumulation by C. vishniaccii utilizing amaranth seeds as substrate could serve as a feasible feedstock for biodiesel production.

This work aimed to evaluate the sorption capacity of natural sorbents (wool, moss, straw, peat) and their composites during the sorption of crude oil and of diesel overspread on the water surface. The work presents the research results of the maximum sorption capacity of the sorbents/their composites using crude oil/diesel; the sorption capacity of the sorbents/their composites when crude oil/diesel is spilled on the water surface; and the research results of the unrealized part of the crude oil/diesel in the sorbents. The results of the analysis showed that all the sorbents and their composites have their selectivity to crude oil less than 50%. Also the results showed that the distribution of diesel and water in the sorbents and their composites is very different compared with the distribution of crude oil during the sorption analyses. In total, the diesel in the liquid mass absorbed by the straw and the peat amounted to 17 and 20%, respectively. This shows that these sorbents are much more selective for water but not for diesel. A larger part of the diesel was in the liquid amount absorbed by the composites—up to 33%. Accordingly, the use of these composites in watery environments is much more effective than the use of individual sorbents. The composition of sorbents in the composite enhanced both the hydrophobic and the oleophilic properties; as a result, a more effective removal of the diesel and oil from the water surface was achieved.