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The difficulty of removing emerging contaminants, including BPA, from water supply and wastewater treatment plants represents a major obstacle to controlling these compounds in freshwater. This study evaluated and compared the toxicity of BPA in solution to the tropical organism Chironomus sancticaroli, before and after the adsorption process of the compound using commercial powdered activated carbon (PAC) and activated husks from the seed of the Moringa oleifera plant (C-MOH300), a natural waste product. Emergence rate, survival, sex ratio, and insect emergence time were evaluated in the BPA toxicity tests. The batch adsorption experiments were carried out using 35 mg L⁻¹ and 400 mg L⁻¹ of PAC and C-MOH300, respectively. The initial measured concentration of 3.86 mg L⁻¹ of BPA was selected for the adsorption experiments because it negatively affected the emergence rate and survival of the insect larvae in long-term chronic toxicity tests. Both adsorbents were able to reduce the concentration of BPA in solution, with PAC being more efficient at removing the compound, providing a 40% reduction. After adsorption with both adsorbents, the solution did not cause chronic toxic effects for C. sancticaroli. M. oleifera seed husk was as effective as PAC in reducing the ecotoxicological effects of the emerging contaminant on the benthic organism. The data produced in this study contributes to the knowledge of alternative water treatment methods using natural waste.

Acid rain can dissolve carbonate rocks and affect karst carbon sinks. This study investigated the effect of acid rain on the dissolution of carbonate rocks within a karstic soil–carbonate rock system and quantified the relationship between the carbon sink and karst carbon sink flux. A subtropical karst spring catchment in southwestern China was chosen as the study area. The hydrochemistry of acid rain and spring water, along with the δ¹³C of dissolved inorganic carbon (DIC), was systematically monitored. NH₄⁺, H₂SO₄, and HNO₃ from precipitation contributed 3.57%, 3.49%, and 1.57% to carbonate rock dissolution, and 1.74%, 1.70%, and 0.77% to groundwater DIC, respectively. These acidic ions reduced the karst carbon sink flux by approximately 17.37%. The carbon sink flux reached 43.93 mg C/L during the wet season, whereas the karst carbon sink flux was 11.61 mg C/L. Overall, the total carbon sink flux in the spring catchment was about 3.8 times higher than the karst carbon sink flux. The dissociation of carbonic acid produces H⁺, which can be exchanged with soil base ions. This process contributed more DIC to groundwater in the Yaji karstic soil–carbonate rock system than direct carbonate rock erosion by H⁺ from carbonic acid dissociation. While this study demonstrates that karstic soil processes significantly buffer acid rain and strengthen the carbon sink effect, their wider applicability may be limited by site-specific factors such as soil composition, hydrological conditions, and land use.

Heavy metals such as lead (Pb(II)) are highly toxic and persistent heavy metals that can accumulate in the environment and living organisms, even at trace levels, causing serious health issues such as neurological and kidney disorders. Therefore, its accurate and rapid detection is crucial for environmental monitoring, pollution control, and public health protection. Compared to conventional analytical techniques, electrochemical sensing offers a simple, cost-effective, and highly sensitive approach for real-time Pb(II) monitoring. In this work, a simple reflux strategy is used to combine reduced graphene oxide (RGO) with copper tungstate (CuWO₄) nanoparticles (NPs) to create a CuWO₄/RGO nanocomposite (NPS). The lead ion (Pb (II)) was detected electrochemically using the generated CuWO₄/RGO NPS. The well-defined CuWO₄/RGO NPS is applied as a modifier on glassy carbon electrodes (GCE) to create CuWO₄/RGO@GCE. Several characterization techniques, including Energy-dispersive X-ray spectroscopy (EDS), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and powder X-ray diffraction (PXRD), were used to analyze the synthesized GO, RGO, CuWO₄, and CuWO₄/RGO NPS. Cyclic voltammetry (CV) and differential pulse anodic stripping voltammetry (DPASV) were used to assess the electrochemical detection of Pb (II). With a limit of detection (LOD) of 0.4 ppb and a linear range of 2–20 ppb, the CuWO₄/RGO@GCE electrode demonstrated exceptional sensitivity of 0.001A/V, selectivity, and repeatability. In the meantime, real sample analysis using the CuWO₄/RGO@GCE electrode has shown improved recovery findings of 96.8 – 99.8%.

Superparamagnetic Fe₃O₄ nanoparticles were specifically designed with a polydopamine (PDA) and folic acid (FA) coating to enhance the availability of organic functional groups at the surface, facilitating the interactions with transition metal ions and drugs. Such nanoparticles were here denoted Fe₃O₄@PDA-FA. Their synthesis and characterization were carefully performed, including thermogravimetric analysis, Fourier transform infrared (FTIR) spectroscopy, dynamic light scattering (DLS), zeta potential measurements, and transmission electron microscopy (TEM). The capture of cobalt(II), copper(II), and zinc(II) ions was successfully demonstrated, revealing the great potential of the Fe₃O₄@PDA-FA nanoparticles in magnetic nanohydrometallurgy (MNHM). The Fe₃O₄@PDA-FA nanoparticles also exhibited good performance in the capture and magnetic transport of buparvaquone, a drug with pharmacological activity against leishmaniasis, as well as antitumor action. The observed drug capture response exhibited a pronounced enhancement in the presence of cobalt(II) ions, which seems to play a role in mediating the interaction between the target molecule and the PDA-FA coating.

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According to International Agency for Research on Cancer (IARC), PM_2.5 is classified as a group 1 human carcinogen. IQAir (2023) reported that India is the third most polluted country globally, after Bangladesh and Pakistan. This study investigates the spatial and temporal variations of PM_2.5 and associated health risks across India from 2019 to 2023. The studied PM_2.5 levels in India consistently surpassed the National Ambient Air Quality Standards (NAAQS) of India, China, the USA, Canada, European Union (EU), and World Health Organization (WHO). Seasonal distribution of PM_2.5 indicates that the highest concentration occurs in winter. Among the top twenty most polluted cities, Bihar has eight, and Uttar Pradesh has four. Among 31 studied states/Union Territories (UT), 17 (54.84%) exceeded the Indian NAAQS levels, and 31 (100%) violated the WHO guidelines. Similarly, for 271 cities, 175 (63.64%) cities exceed the Indian NAAQS, and all 271 (100%) cities violate the WHO guidelines. The significant number of days in a year exceeded the national and international threshold levels. To meet the Indian NAAQS levels, Delhi must reduce PM_2.5 to 20 μg/m³, and the top nine states reduce 10 μg/m³ each from the present levels. To achieve the WHO guideline (5 μg/m³), India would need approximately 10 to 20 years with a 20 to 10% annual reduction rate. The health risk study showed that the Hazard Quotient (HQ) threshold limits (HQ < 1) significantly exceed (2 to 10 times high). The premature mortality due to PM_2.5 in India is from cardiovascular disease (CVD) at 1,945,584, followed by ischemic heart disease (IHD) at 1,252,188, chronic obstructive pulmonary disease (COPD) at 725,367, and stroke at 552,974 and high health risk observed in Indo-Gangetic Plain (IGP) region. Among the total premature deaths, CVD, IHD, COPD, and stroke contributed about 43.47%, 27.97%, 16.21%, and 12.35%, respectively. IHD is the primary cause of premature deaths in India among cardiovascular diseases. This study will help the policy makers at national and regional levels and highlight the urgent need for region-specific pollution control strategies, focusing on crucial emission sources to mitigate health risks and improve air quality across India.

This study investigates laser-induced decoration of soda-lime glass, emphasizing how laser parameters, particularly power and scanning speed, affect surface morphology and optical properties. An initial analytical model, inspired by existing literature, is developed to predict the dimensions of the laser-induced damaged zone (DZ) at the micro-scale level. A more refined numerical model is then introduced to reduce simplifying assumptions and access hard-to-measure physical values. Experimental validation enables the comparison of both models. Results show that the analytical model reliably predicts DZ width for moderate fluences (ϕ* < 3.1), while the numerical model yields better accuracy at higher fluences. For DZ depth, the analytical model is effective only up to ln(ϕ/Vₘ) < 5 (~ 100 μm); beyond that, it diverges. The numerical model offers more consistent results across the entire range, though with a slight underestimation. The study also explores the potential for reducing process parameters through the definition of a meta-parameter analogous to fluence, supporting broader industrial applications.

This paper explores the properties of a partially coherent modified anomalous vortex beam (PCMAVB) in maritime turbulence. The propagation formula of the PCMAVB through the considered turbulence media has been derived using the extended Huygens-Fresnel integral. Numerical examples are provided to examine how maritime turbulence strength influences the intensity distribution under various initial beam parameter conditions. The results reveal that the PCMAVB maintains its initial profile over short distances; however, with further propagation, the beam gradually loses its properties, evolving into a Gaussian beam in the far field. The rate of increase in the central peak intensity accelerates as the turbulence’s constant structure rises and the turbulence’s inner scale size diminishes, or as beam parameters such as coherence length and topological charge are reduced. Moreover, lower values of the modification parameter δ improve the beam’s resistance to turbulence at short distances. This suggests that the modification parameter introduces a new aspect for controlling the properties of hollow beams. The obtained results may prove useful for practical applications of PCMAVB in free-space optical communications.

Grasping the current situation of green development in the Pearl River Basin can provide ideas for deciphering the high-quality development of the Pearl River Basin, and provide Chinese experience for the governance and protection of the world's great rivers. This paper takes 47 prefecture-level cities in the Pearl River basin (PRB) as the research object, measures and analyzes the green development efficiency (GDE) through the Super-SBM model with undesired output, and explores the influencing factors of GDE in the PRB with the help of Tobit model. The study found that: First, the level of GDE of PRB shows an N-shaped change, and most of the GDE in the PRB is in a relatively ineffective state. Second, the GDE of the PRB exists as an obvious differentiation phenomenon, and the regional development is extremely unbalanced. During the study period, the kernel density curve of GDE in the PRB showed an obvious double-peak coexistence phenomenon, and the height difference between the main and side peaks gradually increased with time. Last, Economic development (ED), industrial structure (IS), foreign capital utilization (FCU), and environmental regulation (ER) can contribute to the improvement of the GDE of PRB. At the same time, the impact of the technological level (TEC) on the GDE of PRB is negative, indicating that technological innovation has not become the source of growth of the GDE of PRB. Therefore, it is suggested that the ecological protection and high-quality development of the PRB should be upgraded to a national strategy at the national level, and the Pearl River Commission should make a unified deployment for the green transformation and development of the PRB. All regions in the PRB should have global thinking and coordinated development, proceed with the modernization of the governance system and governance capacity, continuously narrow the regional gap, and improve the efficiency of green development. Strengthen support for scientific and technological innovation, build a river basin ecological industry system, and promote green development and transformation.