This study offers an investigation of the catalytic activity of TiO₂/SiO₂ during oxidative desulfurization (ODS) of a model fuel that includes dibenzothiophene (DBT), using hydrogen peroxide (H₂O₂) as a green oxidant in the absence of UV irradiation. For the first time, though a novel and simple protocol, TiO₂/SiO₂ nanohybrid was synthesized using ascorbic acid and glycerol as green complexing and polymerizing agents, respectively. The TiO₂/SiO₂ catalyst was thoroughly characterized by XRD, FT-IR, nitrogen adsorption-desorption measurements, TEM, FESEM, and TGA. Results revealed a high catalytic oxidative activity for the catalyst in the removal of DBT regarding sulfur removal up to 99.4% within 20 min under optimum reaction conditions. The main factors affecting the ODS process, including catalyst dosage, temperature, O/S molar ratio, and different oxidizing agents, were evaluated to identify optimum conditions. The desulfurization efficiency of the recoverable catalysts showed no loss in activity after four times. The present article suggests a new and green method for the synthesis and characterization of an efficient catalyst (TiO₂/SiO₂) in deep oxidative desulfurization at 25 °C and removal of refractory organosulfur compounds that yield ultra-low sulfur fuels. Also, it proved to have a much higher catalytic oxidation capacity when compared to pure TiO₂.

Despite the exponential increase of studies on plastic debris in recent years, there are still few works focusing on the problem as it relates to inland waters: little is known about the accumulation and dispersion dynamics on lake shores, and there are no standardized sampling methods for monitoring purposes. The accumulation of plastic litter in natural habitats also threatens the resident organisms. In this paper, we investigated the abundance and accumulation of plastic particles, ranging in size from 1 to 50 mm, from the beach sediment of three volcanic lakes in Central Italy: Albano, Bracciano, and Vico. The collection was designed to define the most important variables that one must consider in order to obtain a representative sample of plastic litter in a lake environment. In view of the high heterogeneity of sampling protocols used, comparison among the obtained results is limited and sometimes impossible. By using one of the proposed sampling methodologies, and critically analyzing the results, we aimed to highlight a possible monitoring criterion and to identify specific elements that can be meaningful and representative. The samples were collected in May and September 2017. For each lake, we sampled plastic items and sediments from two beaches. Albano contained the largest amount of plastic (in weight), while Bracciano had the largest number of particles. Our observations lead us to infer that the number of particles is the parameter most sensitive to environmental variations, as well as the more suitable for monitoring with greater definition the differences between sites. Moreover, sampling should be taken in different seasons, following a sampling pattern that includes at least two beaches placed in strategic positions with respect to wind and waves.In order to identify new indicators to evaluate the entry points of plastic into the food web, we collected, from the same sites analyzed, some specimens of the Talitrid Amphipod Cryptorchestia garbinii, a detritivorous species having a critical role in debris turnover of these environments. To investigate the microplastic (MP) ingestion in natural conditions, we analyzed their digestive tracts with both Nile red staining method and micro-FTIR spectroscopy. The analyses confirmed that C. garbinii was able to ingest plastics in natural conditions. Therefore, it can signify one of the entry points for microplastics (MPs) in the trophic chain. This observation constitutes the first evidence of MP ingestion in this species.

Evaluation of geogenic carbon fluxes between solid Earth and its atmosphere is essential to understand the global geological carbon cycle. Some of the key geogenic CO₂ suppliers are the magmatic mantle and metamorphic degassing from active and quiescent volcanoes, fault zones, geothermal systems and CO₂ rich groundwater. Indian Himalayan geothermal field hosts about 340 geothermal springs in natural as well as artesian condition that eject hot waters and volatiles with varied temperature and chemical composition. These sites provide an opportunity to analyse tectonically driven gas emissions and their impact on regional and global climate. Here we adopt a method for direct measurement of Dissolved Inorganic Carbon (DIC ≈ HCO₃) concentration in the geothermal springs to estimate geogenic CO₂ flux from an active region based on water discharge and area of geothermal system between the tectonic boundaries of the Main Central Thrust (MCT) and Main Boundary Thrust (MBT) of the Garhwal (Northwest) Himalaya. In the study area, geothermal spring water contain high δ¹³CDIC ratio (− 8.5‰ to + 4.0‰ VPDB), and among the major ions, bicarbonate (HCO₃⁻) varies by an order of magnitude from 1697 to 21,553 μEq/L; chloride and sodium vary from 90 to 19,171 μEq/L and 436 to 23181 μEq/L. The elevated concentration of Cl⁻ and Na⁺ in geothermal spring waters suggests affinity towards their deeper origin. These geothermal springs cover a large area of nearly 10,000 km² of the Garhwal region showing a significant discharge of CO₂ rich water with an estimated carbon dioxide degassing flux of ~7.2 × 10⁶ mol/year to the atmosphere. Considering widespread occurrences of geothermal springs in tectonically active areas worldwide, the proposed direct measurement of DIC may be used as a reliable tool to estimate CO₂ fluxes in different active orogenic settings within the Earth system. Results of stable isotopes of δ¹⁸O ₍VSMOW₎ and δD ₍VSMOW₎ in these geothermal spring waters follow the Global Meteoric Water Line (GMWL), suggesting affinity of their recharge through the meteoric origin.

Hepatocellular carcinoma (HCC), a common type of human malignancies, leads to increasing incidence and fairly high mortality. An increasing number of studies have verified that long noncoding RNAs (lncRNAs) played key roles in the development of multiple human cancers. As a biomarker, SLC16A1-AS1 has been reported in non-small cell lung cancer (NSCLC) and oral squamous cell carcinoma (OSCC). Thus, we decided to investigate whether SLC16A1-AS1 exerts its biological function in HCC. In this study, we discovered that SLC16A1-AS1 was obviously downregulated in HCC tissues and cells. Overexpression of SLC16A1-AS1 inhibited HCC cell proliferation, invasion, and epithelial-mesenchymal transition (EMT) process as well as promoted cell apoptosis. Moreover, SLC16A1-AS1 was confirmed to enhance the radiosensitivity of HCC cells. Molecular mechanism exploration suggested that SLC16A1-AS1 served as a sponge for miR-301b-3p and CHD5 was the downstream target gene of miR-301b-3p in HCC cells. Rescue assays implied that CHD5 knockdown could recover the effects of SLC16A1-AS1 overexpression on HCC cellular processes. In brief, our study clarified that SLC16A1-AS1 acted as a tumor suppressor in HCC by targeting the miR-301b-3p/CHD5 axis, which may be a promising diagnostic biomarker and provide promising treatment for HCC patients.

Currently, in situ capping is a typical popular geoengineering method for eutrophication control. It is crucial to better understand the effect of microenvironment change due to capping, such as amended calcium peroxide material (ACPM) and Phoslock®, on phosphorus (P) adsorption and immobilization under the addition of external P. The microenvironment in sediment was presented by the concentration of O₂, NH₄⁺, and Fe²⁺ and microbial activity. The P removal and immobilization were also analyzed. The results show that the stronger oxidation in the microenvironment under the capping with ACPM was due to the higher reduction of NH₄⁺ and Fe²⁺ and the higher increase of microbial activity, compared to Phoslock®. Although, under the capping of ACPM, less amount of external P was removed and there was a faster release of sedimentary P, compared to Phoslock®, ACPM improved the transformation of P from mobile P fractions to inert P fractions. In addition, sedimentary P under the capping of ACPM presents less release than that under the capping of Phoslock® during the anaerobic incubation. However, the settlement of suspended solids decreased the function of capping. All these results indicated that the mechanism of P removal and immobilization was different under the capping of ACPM and Phoslock®.

Ever since China’s “housing reform” in 1998, the level of real estate investment in its cities has continued to rise, leading to the occupation of green space, rapid population concentration, and a severe mismatching of financial resources. At the same time, urban air quality has changed drastically for the worse, with PM2.5 becoming the primary air indicator of concern for many cities in recent years. The existing literature has obtained sufficient results on the influence factors of air pollution, but rarely presents the relationship between real estate investment and air pollution, especially using multiple cities as the sample. This paper thus examines the impact of real estate investment on air quality using a sample of 261 prefecture-level cities in China over the period 1999–2016 through several econometric models. First, the two-way fixed-effect model shows an inverted U-shaped relationship between PM2.5 concentration and real estate investment, but most cities have not yet crossed the turning point, and that real estate investment negatively impacts air quality. Second, the indirect effect of real estate investment on PM2.5 concentration comes from its non-linear impact on urban green coverage, population density, and industrial structure, which has been verified by Hayes and Preacher’s (Behav Res 45:627–660, 2010) mediation effect with non-linear forms. Third, heterogeneity analysis indicates that an inverted U-shaped relationship also exists in the subsamples, and that real estate investment in cities with more people, higher GDP, and greater development level is more likely to increase rather than mitigate air pollution. Therefore, cities should promote the green development of real estate and related industries by enhancing environmental awareness, guide the population flow toward the coordinated development between real estate investment and population distribution, and encourage environmentally friendly technological progress via a better rational allocation of financial resources.

Graphitic carbon nitride (g-C₃N₄) is paying attention lately owing to its interesting characteristics and substantial application in improving environmental and energy concerns. Nevertheless, the photocatalytic activity of g-C₃N₄ is constrained by the inertness of the surface and particle aggregation during photocatalytic activity. Herein, we report the preparation of g-C₃N₄ with honeycomb-like morphology (HC-C₃N₄) via thermal condensation of prepared SiO₂ templates and dicyandiamide. The etching out of the SiO₂ templates by NH₄HF₂ created hollow or macropores in the C₃N₄ matrix resulting in its structural changes. Similar, to the bulk C₃N₄, the HC-C₃N₄ exhibited higher photocatalytic CO₂ reduction in hydrocarbons. This improved photocatalytic achievement is associated with higher specific surface area, excellent visible light absorption capability, higher electron donor density, easy mass diffusion of materials for surface reaction, and effective segregation of photogenerated charge carriers. Furthermore, the HC-C₃N₄ honeycomb structure was deposited with Ni(OH)₂ clusters which showed remarkable CO₂ reduction activity of 1.48 μmolh⁻¹ g⁻¹ of CH₄ and 0.73 μmolh⁻¹ g⁻¹ of CH₃OH generation which is 3.5 and 4.3 times higher CO₂ reduction activity compared with bulk C₃N₄ clustered with Ni(OH)₂ particles. This comprehensive study demonstrated that HC-C₃N₄ nanostructured polymeric semiconductor is envisaged to have great potential in the application of a variety of fields such as photocatalysis, sensor technology, and nanotechnology.

Over the last 50 years, urban population of Turkey has grown from 25 to 75%. Urbanization is highly linked with one of the most important global problems which is global warming through accelerating economic growth, energy consumption, and trade openness that are considered to be the main indicators of climate change in environmental literature. The main purpose of the present research is to examine the long-run effect of economic growth, energy consumption, trade openness, and urbanization on environmental degradation and causal link among the indicators under consideration in Turkey by taking into account the moderating role of urbanization over the period of 1960–2016. Aiming to establish robust findings, this study utilized both traditional and modern econometric techniques, including Bayer and Hanck cointegration, Gregory and Hansen cointegration, fully modified ordinary least squares (FMOLS) and dynamic ordinary least square (DOLS), Granger causality, Toda-Yamamoto causality, and Gradual Shift causality tests. The cointegration tests reveal that carbon dioxide (CO₂) emissions and economic growth, energy consumption, trade openness, urbanization, and the moderating role of urbanization are cointegrated. The outcomes of the long-run estimators—FMOLS and DOLS—reveals that environmental Kuznets curve (EKC) hypothesis is valid and the existence of moderating role of urbanization on indicators of CO₂ emissions is confirmed for the case of Turkey. Moreover, the causality tests mirror that while energy consumption, trade openness, and urbanization are important for predicting CO₂ emissions, the moderating role of urbanization leads CO₂ emissions in the short run.

Clothianidin served as the model pollutant to investigate the performance and mechanism of pollutant removal by dielectric barrier discharge plasma (DBD) combined with the titanium dioxide-reduced graphene oxide (rGO-TiO₂) composite catalyst. In this study, different ratios of titanium dioxide-graphene catalysts were loaded onto honeycomb ceramic plates via the sol-gel method, and the modified catalytic ceramic plates were characterized by XRD, SEM, FTIR, DRS, and energy dispersive X-ray. The results suggested that the rGO-TiO₂ was well loaded on the surface of the honeycomb ceramic plates. According to the results of the characterization experiments and the degradation of the clothianidin solution with different proportions of the catalyst, 8 wt% rGO-TiO₂ was selected as the optimum ratio for degradation. Clothianidin degradation efficiency was significantly influenced by input power, clothianidin concentration, pH value, liquid conductivity, free radical quencher. Finally, six degradation products of clothianidin were identified by HPLC-MS, and the possible transformation pathways of clothianidin degradation were identified. Graphical abstract