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Study region: The Ailaoshan National Nature Reserve forest is a mountainous water catchment area for the Lancang River basin and a subtropical ecological conservation area in southwest China. Study focus: The study aimed to understand how water fluxes in a subtropical forest responds to extreme weather disturbances and their recoveries in the post-damage years. We used eddy covariance data (2010–2019) to investigate the evapotranspiration (ET), transpiration (T), evaporation (E), and canopy conductance (Gc) before and after an extreme snow event in 2015. New Hydrological Insights: In the snow damage year, the leaf area index (LAI) decreased by 49 % compared to the pre-damage levels. The severe vegetation damage caused a significant decrease in ET, T, E, and Gc by 35 %, 36 %, 23 %, and 33 %, respectively, compared to the pre-damage levels. T returned to its pre-damage level in 2016, one year after the snow damage. In contrast, LAI, ET, E and Gc recovered to their pre-damage levels in 2018, four years after the initial damage. Reduced ET caused a strong positive RFET, which diminished forest evaporative cooling and resilience. Our results suggest that the delayed E recovery enables water reserves in the ecosystems to be used through T to support rapid understory vegetation growth. This mechanism plays critical in bolstering ecosystem resilience as it facilitates swift recovery following disturbances in subtropical forests.

This article explores the development and applications of a Cu3N/GCE-based sensor using differential pulse voltammetry (DPV) for selective uric acid (UA) detection in clinical analysis. The sensor achieves a limit of detection (LOD) of 2.57 × 10−8 M and a quantification limit (QL) of 8.102 × 10−8 M, demonstrating its capability to precisely quantify minute UA concentrations. With rapid responsiveness and reusability over 25 days, it offers cost-effective monitoring of UA levels, even in complex sample matrices. Cu3N also exhibits high efficiency in degrading methylene blue (MB), achieving 87.7% degradation under optimized conditions, suggesting its potential as a photocatalyst for environmental remediation, particularly in dye degradation processes. Overall, Cu3N-based technologies show promise in sensitive UA detection for clinical diagnostics, environmental remediation, and industrial catalysis, highlighting its versatility and broad applicability across scientific and practical domains.

Vanadium nitride-poly (0-methoxy aniline)- poly(3,4-ethylene dioxythiophene) (VN-POMA-PEDOT) hybrid was synthesized via ammonolysis and chemical oxidative polymerization technique using VN-POMA-PEDOT/GCE with electrocatalytic activity has two dimensional VN hierarchical porosity with POMA-PEDOT structure created VN-POMA-PEDOT modified GCE working electrode. Donor-acceptor behavior and double-layer growth enable enhanced electrochemical performance and catalytic activity of mebendazole (MBZ). This work investigated the electrochemical sensing conduct of a VN-POMA-PEDOT hybrid composite towards MBZ. The detection limit (DL) and quantification limit (QL) were determined to be 2.192 × 10−9 μM μA−1 and 5.245 × 10−9 M μA−1. Estimation of anti-interference ability, long-term stability, and reproducibility revealed that the prepared VN-POMA-PEDOT electrode is appropriate for the electrochemical sensing finding of MBZ in real analysis, such by way of anti-helminthic drug milk. The VN-POMA-PEDOT achieved 98.9% efficiency in the photocatalytic degradation of methylene blue (MB) within 50 min with degradation rate 8.3 × 10−3 min−1. The suppleness of this method was confirmed by the hybrid morphology VN-POMA-PEDOT, which shows an enormously superior and enhanced photocatalytic presentation of MB.

Abstract New (NH4)Cd6(P2O7)2 P3O10 nano-multi shapes were prepared by hydrothermal method and which can be examined by various using instruments like X-ray diffraction, FTIR and Raman spectroscopy measurements. These (NH4)Cd6(P2O7)2 P3O10 nanocatalysts were obtained to the monoclinic structure. The (NH4)Cd6(P2O7)2 P3O10 nanocatalyst morphologies were analyzed in SEM instrument and spheres like structures, triangle, cubic and crystal shapes also obtained. Peaks 484, 557 and 1087 cm−1 were corresponds to the M–O and P–O groups, which results were confirmed by FT-IR studies. This (NH4)Cd6(P2O7)2 P3O10 materials synergism can be described in photocatalytic applications. At this juncture, these nanoparticles can be created to the new invention and effectible performed to the Brilliant Green dye efficiency with halogen lamp.

Abstract Background Intrathecal (IT) morphine provides excellent post-operative analgesia, but causes multiple side effects including nausea and vomiting (PONV), pruritus and respiratory depression, particularly at higher doses. The lowest effective dose of spinal morphine in patients undergoing total knee arthroplasty is not known. Methods We evaluated the analgesic efficacy and side effect profile of 100 – 300 μg IT morphine in patients undergoing elective total knee replacement in this prospective, randomized, controlled, double-blind study. Sixty patients over the age of 60 undergoing elective knee arthroplasty were enrolled. Patients were randomized to receive spinal anaesthesia with 15 mg Bupivacaine and IT morphine in three groups: (i) 100 μg; (ii) 200 μg; and (iii) 300 μg. Results Both 200 μg and 300 μg IT morphine provided comparable levels of postoperative analgesia. However, patients that received 100 μg had greater pain postoperatively, with higher pain scores and a greater requirement for supplemental morphine. There were no differences between groups with regard to PONV, pruritus, sedation, respiratory depression or urinary retention. Conclusion Both 200 μg and 300 μg provided comparable postoperative analgesia, which was superior to that provided by 100 μg IT morphine in patients undergoing total knee arthroplasty. Based on these findings, we recommend that 200 μg IT morphine be used in these patients. Trial registration ClinicalTrials.gov Identifier NCT00695045

Nanotechnology (NT) and nanoparticles (NPs) have left a huge impact on every field of science today, but they have shown tremendous importance in the fields of cosmetics and environmental cleanup. NPs with photocatalytic effects have shown positive responses in wastewater treatment, cosmetics, and the biomedical field. The chemically synthesized TiO2 nanoparticles (TiO2 NPs) utilize hazardous chemicals to obtain the desired-shaped TiO2. So, microbial-based synthesis of TiO2 NPs has gained popularity due to its eco-friendly nature, biocompatibility, etc. Being NPs, TiO2 NPs have a high surface area-to-volume ratio in addition to their photocatalytic degradation nature. In the present review, the authors have emphasized the microbial (algae, bacterial, fungi, and virus-mediated) synthesis of TiO2 NPs. Furthermore, authors have exhibited the importance of TiO2 NPs in the food sector, automobile, aerospace, medical, and environmental cleanup.

The Indian coal fly ash (CFA) is composed of 5-15% ferrous fractions. The variation in percentage depends on the source of coal and the operating conditions of the thermal power plants. The present research work reports the recovery of ferrous particles from CFA by the wet magnetic separation method. The morphological, elemental, and chemical properties of the extracted ferrous fractions were analyzed. In order to achieve surface-modified ferrospheres, the extracted ferrospheres were treated with concentrated HCl followed by sonication. The instrumental analysis reported the ferrous composition is around 16% by weight and belongs to class F. The toxicity of CFA was determined on normal human lung (BEAS-2B) cells using MTS assay. The results showed that CFA’s induced cell toxicity in a dose-dependent manner. The ferrous particles were spherically shaped with various sizes ranging from 200 nm to 7000 nm. It was crystalline in nature and is a mixture of hematite and magnetite. The particles were found to be associated with alumina, silica, oxygen, and traces of Ca, Mg, Ti, and C. The surface-modified ferrospheres were used for the remediation of Azure A dye by batch adsorption study. The removal percentage of dye was 25.03%, within 30 minutes at neutral pH, i.e., 7.2. The surface-modified ferrospheres show potential as an alternate, more economical, and reusable adsorbent for the remediation of Azure A dye in the industries or in common effluent treatment plants. Moreover, the recovery of surface-modified ferrospheres using an external magnet and the reuse of the particles make the material much economical for dye removal at an industrial scale.

Incense stick ash (ISA) has traces of toxic heavy metals which have an adverse effect on the environment. Every year, tonnes of ISA are disposed of in rivers and other water bodies which leads to water pollution and affects the natural water resources. ISA has several value-added minerals which could be modified or functionalized for environmental cleanup. Here, in the current research work, ISA was transformed into a flower-like noble porous material by mixing ISA and NaOH in a 1 : 1 ratio followed by calcination at 600°C for six hours in a muffle furnace. The developed material was analyzed by sophisticated instruments for the identification of the properties. The microscopic techniques revealed the micron-sized flower-like structure, while the XRD showed peaks at 30–33° which indicates the transformation of the calcite and silicate phases into new-phase mineral. FTIR also revealed bands in regions of 500–1200 cm−1 and new bands near 450 cm−1. EDS confirmed the presence of Na in the sintered product and the transformation of the ISA. Finally, the sintered product potential was assayed for the removal of methylene blue dye from wastewater using an adsorption mechanism. The removal efficiency of dye reached up to 70% within one hour only. It was found that the ISA sintered product has the potential to remove MB dye efficiently from wastewater and also reduce solid waste pollution. Microculture tetrazolium assay (MTT) and lactate dehydrogenase (LDH) assays were performed to evaluate the cytotoxicity of the sintered incense stick ash product on RTG-2 cells. The sintered incense stick ash product induced cytotoxicity on RTG-2 cells in a dose-dependent manner. Sintered ISA products have the potential to remove methylene blue dye efficiently from wastewater and reduce solid waste pollution.

Energy leapfrogging (i.e., skipping non-renewable grid infrastructures to micro-grid renewable sources) has been promoted by researchers and politicians as a solution in fighting against climate change and for access to electricity in less developed countries. Despite research on its potential, quantitative measurement of leapfrogging is still required to determine those nations who have utilized energy leapfrogging's promise. In this study, we present a quantitative analysis using World Bank Open Database data from 2000 to 2015, creating an aggregated leapfrogging estimate (ALE) through renewable energy consumption (i.e., percentage of total energy consumption) and access to electricity (i.e., percent of total population with access). We defined the ALE by subtracting (renewable consumption % in 2000 / access to electricity % in 2015) from (renewable consumption % in 2015 / access to electricity in 2000). We included only countries whose renewable energy consumption increased during the study interval. Low-income countries collectively leapfrogged more than other income groups. Somalia (48.11), Togo (3.05), Eswatini (2.76), and Timor-Leste (1.04) all had ALE values greater than 1 (range: 1.7 × 10−5–48.11). We then conducted a policy analysis of these countries, confirming that all four had implemented renewable energy policies to create access to electricity. Our ALE accurately determined countries with energy leapfrogging, uniquely incorporating access to electricity, consistent with the fundamental purpose of leapfrogging as a strategy to increase access. Future studies are needed to understand why low-income countries with low ALEs and access to electricity failed to leapfrog in the past. Future studies are also required to design prospective quantitative statistical models predicting the outcomes of leapfrogging strategies.

Study Region: Lancang River Basin (upper reaches of the Mekong River basin within China). Study Focus: Complex terranes and diverse climates are a bottleneck for understanding the hydrology of rivers originating from the Tibetan Plateau. This study deals with the impact of climate change on water storage in the Lancang River Basin, which is governed by the South Asian monsoon system. We evaluated the spatiotemporal distribution of multi-source precipitation, evapotranspiration, and terrestrial water storage (TWS) to understand the hydrological system in the region. We provide evidence of climate change impacts on TWS and basin discharge over an upstream region of the transboundary river system. New Hydrological Insights for the Region: The Five Gravity Recovery and Climate Experiment (GRACE) products and Global Land Data Assimilation System (GLDAS) TWS display analogous seasonal distribution, even though the amounts differ between them. The GRACE and GLDAS TWS exhibited a significant negative trend in the basin from 2002 to 2016. However, the Center for Space Research (CSR-M) at the University of Texas and the Jet Propulsion Laboratory (JPL-M) mascon solutions concede more severe and much wider TWS reduction than the three spherical harmonic (SH) solutions. In addition, a downward trend was observed for basin discharge over 15 years as a response to climate change (decreased precipitation and increased evapotranspiration). Furthermore, we identified a 2-month time lag between precipitation and TWS, which could be a response to climatic factors along with aquifer properties in a karst dominated region.

Coal fly ash (CFA) is one of the major pollutants around the whole world. At the same time, incense stick ash (ISA) is another waste that is generated in huge amounts in Southeast Asia. Both of these wastes are rich in different types of minerals; for instance, CFA is rich in alumina, silica, and ferrous, while incense sticks ash is rich in calcium and silica. ISA has intermediate to trace amounts of ferrous, alumina, and magnesium. The addition of alkali-rich materials with high Al and Si-containing CFA helps in the formation of zeolites or geopolymers. So, in the current research work, the authors have prepared a CFA: ISA mixture in the ratio of 1:1, followed by mixing them with NaOH, CaOH2, and KOH in a dry state in a crucible. Further, all these mixtures were then calcined at 600 °C for six hours in a muffle furnace. Further, the developed products were analyzed by various sophisticated instruments for detailed information. Finally, the developed material’s potential was assessed for the remediation of malachite green from the aqueous solution by batch adsorption study. The developed adsorbents efficiently removed the dye from the aqueous solutions within one hour. The kinetic study revealed that the dye removal followed a pseudo-second-order reaction. Finally, the developed material was also assessed for its suitability as an adsorbent by observing the effect of leaching of potassium, aluminum, and silica from the adsorbent surface into the water systems. Such approaches will solve the problem of solid waste disposal arising from both the ashes.

At present, chemical Si/Al sources are mainly used as precursor materials for the manufacturing of zeolites. Such precursor materials are quite expensive for commercial synthesis. Here, we have reported the synthesis of Ca-based zeolite from incense stick ash waste by the alkali-treatment method for the first time. Incense stick ash (ISA) was used as a precursor material for the synthesis of low Si zeolites by the alkali-treatment method. The as-synthesized zeolites were characterized by various instruments like particle size analyzer (PSA), Fourier transform infrared (FTIR), X-ray diffraction (XRD), field emission scanning electron microscope (FESEM), electron diffraction spectroscopy (EDS), transmission electron microscopy (TEM), and X-ray fluorescence (XRF). FTIR and XRD helped in the identification of the microstructure and crystalline nature of the zeolites and also confirmed the synthesis of Ca-based zeolite with two thetas at 25.7°. The microscopic analysis by FESEM and TEM exhibited that the size of synthesized Ca-rich zeolites varies from 200 to 700 nm and they are aggregated and cuboidal in shape. Additionally, structural, electronic, and density of states’ characteristics of gismondine (Ca2Al4Si4O16·9H2O) structures were evaluated by computational simulations (first principle, density functional theorem). The structural optimization of structures was carried out in the first stage under the lowest condition of total energy and forces acting on atoms for the lattice constant, as well as the available experimental and theoretical findings. The present research approach predicted the transformation of ISA waste into a value-added mineral, i.e., zeolite, which was further used for the removal of both heavy metals and alkali metals from fly ash-based wastewater using inductively coupled plasma-optical emission spectroscopy (ICP-OES).

Platinum aminophosphate (PtAP) was synthesized by simple chemical method. The synthesized sample was characterized by XRD, DRS-UV, FT-IR, Raman, FE-SEM with EDX and HR-TEM techniques. The PtAP nanoparticles phase was confirmed by X-Ray diffraction patterns. Pt–O stretching vibrations and M-O-M vibrational bands of the metal oxides and phosphate groups were investigated by FT-IR spectroscopy. Bandgap energy was determined by diffuse reflectance UV–visible spectroscopy. PtAP flakes like surface morphology and elemental mapping analysis were carried out by FE-SEM with EDX. The synthesized catalyst is high photodegradation of methyl orange by visible light irradiation. As synthesized Platinum aminophosphate nanomaterial was screened by antimicrobial activity against human bacterial pathogens, like Gram-positive bacteria Staphylococcus aureus, Gram-negative bacteria Pseudomonas aeruginosa, Escherichia coli and fungal pathogen Candida albicans. These results determined best activity against all the tested human pathogens. Here, higher zone of inhibition was observed in gram positive and fungal pathogens, which results was compared to gram negative bacteria. The Platinum aminophosphate nanomaterial Minimal inhibitory concentration (MIC) was tested and its shows 99.9% of cell death from the 8 ​μg per m/L for C. albicans as the best inhibition concentration appeared.

With rapid industrialization, there is an ever-increasing demand for iron oxides, calcium oxides, aluminum oxides, silica, and zeolites as raw materials for various industries, but reserves of such metal oxides are continuously diminishing. Therefore, there is an urgent need to explore new alternatives for such value-added minerals. One such material is incense stick ash (ISA), which is among the most unexplored byproducts from residential and holy places. Currently, ISA is of no use and it is disposed of in millions of tons (MTs) in rivers and other water bodies in India due to its sacred value. The major chemical composition of ISA is calcium, silica, alumina, ferrous minerals, magnesium, and traces of Na, K, P, Ti, etc. Major fractions of ISA, i.e., 50–60%, are made up of calcium and magnesium oxides; 20–30% of ISA is made up of silica, alumina, and ferrous minerals, as revealed by X-ray fluorescence spectroscopy (XRF). In the present research work, methods of recovery of value-added micro and nano minerals from ISA are suggested, using cost-effective techniques and an eco-friendly approach. Firstly, magnetic fractions were recovered by a magnetic separation method; then, alumina, silica, and calcium oxides were synthesized from non-magnetic fractions. The confirmation of the synthesized and extracted nanomaterials was done by Fourier transform infrared spectroscopy (FTIR), particle size analyzer (PSA), X-ray diffraction (XRD), field emission scanning electron microscopy with electron diffraction spectroscopy (FESEM-EDS), and transmission electron microscopy (TEM). The purity of synthesized particles varied from 40–80%. In the future, ISA will prove to be an alternative resource material for Fe, Ca, Si, C, Al, and zeolites, which will minimize solid waste pollution and water pollution arising due to the disposal of ISA into water bodies.

Evapotranspiration (ET) plays a crucial role in water balance within the global hydrological cycle. Timely assessment of ET products can provide the scientific basis for quantitative analysis of hydrological cycle processes and water resources assessment. In this paper, four high spatial resolution remote sensing ET products—the Moderate-resolution Imaging Spectroradiometer global terrestrial evapotranspiration product (MOD16), the ET product based on Penman–Monteith–Leuning equation version 2 (PML-V2), the ET product based on the Breathing Earth System Simulator (BESS) and the ET product of the Global LAnd Surface Satellite (GLASS)—were firstly assessed using the eddy covariance (EC) of different vegetation types in the Lancang–Mekong River Basin (LMRB). To fully assess the performances of these four products, spatiotemporal inter-comparisons and literature comparisons were also conducted across different climatic zones. The results are summarized as follows: (1) MOD16 does not perform well as compared to the other three products, with its Root Mean Square Error (RMSE) being higher than GLASS, PML-V2 and BESS, which are approximately 0.47 mm/8-day, 0.66 mm/8-day, and 0.90 mm/8-day, respectively; (2) the performance of each product varies across different vegetation types, and even within the same climate zone. PML-V2 performs best in evergreen broadleaf forests, BESS performs best in deciduous broadleaf forests and croplands, and GLASS performs best in shrubs, grasslands and mixed vegetation; (3) each product can well reflect the spatial difference brought by topography, climate and vegetation over the entire basin but all four ET products do not show either a consistent temporal trend or a uniform spatial distribution; (4) ET ranges of these four products over LMRB are consistent with previous literature in evergreen broadleaf forests, deciduous broadleaf forests, needleleaf forests and mixed forests in other regions with the same climate zones, but they show great differences in croplands, grasslands and shrubs. This study will contribute to improving our understanding of these four ET products in the different climatic zones and vegetation types over LMRB.

Textile industries are the largest consumer of synthetic dyestuff compounds and consequently, they are the prime contributor of colored organic contaminants to the environment. The dye compounds when released in soil or freshwater resources such as rivers, cause a potential hazard to living beings due to their toxic, allergic and carcinogenic nature. Current conventional treatment methods for removal or degradation of such dyestuff materials from water systems are not sufficient, and therefore, there is an immediate need to find efficient and eco-friendly approaches. In this regard, nanotechnology can offer an effective solution to this problem. In the present work, montmorillonite/silver nanocomposite (MMT/Ag nanocomposite) is developed through green synthesis methods using naturally occurring montmorillonite (MMT) clay and silver nanoparticles. The material was characterized by using a particle size analyzer (PSA), UV/Visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscope (FE-SEM), energy dispersive X-ray (EDX) spectroscopy and a Brunner–Emmett–Teller (BET) surface area analyzer. The adsorption efficiency of the nanocomposite and per cent removal of methylene blue (MB) was investigated by using a batch system.

Environmental pollution is one of the major concerns throughout the world. The rise of industrialization has increased the generation of waste materials, causing environmental degradation and threat to the health of living beings. To overcome this problem and effectively handle waste materials, proper management skills are required. Waste as a whole is not only waste, but it also holds various valuable materials that can be used again. Such useful materials or elements need to be segregated and recovered using sustainable recovery methods. Agricultural waste, industrial waste, and household waste have the potential to generate different value-added products. More specifically, the industrial waste like fly ash, gypsum waste, and red mud can be used for the recovery of alumina, silica, and zeolites. While agricultural waste like rice husks, sugarcane bagasse, and coconut shells can be used for recovery of silica, calcium, and carbon materials. In addition, domestic waste like incense stick ash and eggshell waste that is rich in calcium can be used for the recovery of calcium-related products. In agricultural, industrial, and domestic sectors, several raw materials are used; therefore, it is of high economic interest to recover valuable minerals and to process them and convert them into merchandisable products. This will not only decrease environmental pollution, it will also provide an environmentally friendly and cost-effective approach for materials synthesis. These value-added materials can be used for medicine, cosmetics, electronics, catalysis, and environmental cleanup.

Wear is the major mode of failure in machine components made out of polymer and its composites. The low thermal conductivity of the polymer causes heat accumulation near the contact surface and the resulting thermal softening accelerates the wear. In this research work, an attempt is made to enhance the thermal conductivity and wear resistance of the polymer composite using the network reinforcement. Two different composite specimens were prepared with an equal quantity of reinforcement with different geometric form - one with discrete particles and another with the interconnected network. The thermal conductivity and tribological properties of the composites were measured. In particle reinforced composite, the presence of low thermal conductive matrix between the discrete particles act as a barrier for heat conduction and does not enhance the thermal conductivity considerably. In the case of network reinforced composite, the three-dimensional continuity provides an effective heat transfer path and increases the thermal conductivity significantly. The reinforcement in the form of network reduces the wear significantly compared to discrete particle form. The struts in the network reinforcements enhance the strength and arrest the removal of material from the surface.

Every year a million tonnes of calcium rich agro and industrial waste are generated around the whole globe. These calcium rich waste like finger citron, shells of cockle, mussel, oysters etc., and egg shell are biological sources which have various organic compounds. The inorganic calcium rich waste includes gypsum, dolomite, sludge etc., which are produced in surplus amount globally. Most of these by-products are mainly dumped, while few are used for land-filling purposes which leads to the pollution. These agro and industrial by-products could be processed for the recovery of calcium carbonate and calcium oxide particles by physical and chemical method. The recovery of calcium carbonate and calcium oxide particles from such by products make them biocompatible. Moreover, the products are economical due to their synthesis from waste materials. Here, in this current review work we have emphasized on the all the calcium rich agro industries and industrial by products, especially their processing by various approaches. Further, we have also focused on the properties and application of such calcium carbonate and oxide particles for the remediation of organic and inorganic pollutants from the environments. The recovery of such particles from these byproducts is considered not only economical and eco-friendly but it also minimizes the pollution present in the form of solid waste.

Nanoparticles have gained huge attention in the last decade due to their applications in electronics, medicine, and environmental clean-up. Iron oxide nanoparticles (IONPs) are widely used for the wastewater treatment due to their recyclable nature and easy manipulation by an external magnetic field. Here, in the present research work, iron oxide nanoparticles were synthesized by the sonochemical method by using precursors of ferrous sulfate and ferric chloride at 70 °C for one hour in an ultrasonicator. The synthesized iron oxide nanoparticles were characterized by diffraction light scattering (DLS), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray diffraction (XRD), field-emission scanning electron microscopy (FESEM), electron diffraction spectroscopy (EDS), high-resolution transmission electron microscopy (HRTEM) and vibrating sample magnetometer (VSM). The FTIR analysis exhibits characteristic absorption bands of IONPs at 400–800 cm−1, while the Raman spectra showed three characteristic bands at 273, 675, and 1379 cm−1 for the synthesized IONPs. The XRD data revealed three major intensity peaks at two theta, 33°, 35°, and 64° which indicated the presence of maghemite and magnetite phase. The size of the spherical shaped IONPs was varying from 9–70 nm with an average size of 38.9 nm while the size of cuboidal shaped particle size was in microns. The purity of the synthesized IONPs was confirmed by the EDS attached to the FESEM, which clearly show sharp peaks for Fe and O, while the magnetic behavior of the IONPs was confirmed by the VSM measurement and the magnetization was 2.43 emu/g. The batch adsorption study of lead (Pb) and chromium (Cr) from 20% fly ash aqueous solutions was carried out by using 0.6 mg/100 mL IONPs, which exhibited maximum removal efficiency i.e., 97.96% and 82.8% for Pb2+ and Cr ions, respectively. The fly ash are being used in making cements, tiles, bricks, bio fertilizers etc., where the presence of fly ash is undesired property which has to be either removed or will be brought up to the value of acceptable level in the fly ash. Therefore, the synthesized IONPs, can be applied in the elimination of heavy metals and other undesired elements from fly ash with a short period of time. Moreover, the IONPs that have been used as a nanoadsorbent can be recovered from the reaction mixture by applying an external magnetic field that can be recycled and reused. Therefore, this study can be effective in all the fly ash-based industries for elimination of the undesired elements, while recyclability and reusable nature of IONPs will make the whole adsorption or elimination process much economical.

Photocatalysis provides excellent potentials for the complete removal of organic pollutants in environmentally friendly ways and sustainable means of technology. It has been noted that under UV-visible light irradiation, nanostructured semiconductor metal oxides photocatalysts can degrade different organic pollutants. Taking into consideration of the photocatalytic activity, the present study deals with the synthesis of cuprous oxide (Cu _2 O) nanoparticles (NPs) by the sonochemical method and characterized for their physicochemical, optical, and photocatalytic properties. The powdered X-ray diffraction (XRD) analysis confirmed for the cubic phase crystalline structure while the Field emission scanning electron microscopy (SEM) supported for the icosahedron morphology. The bandgap of the synthesized Cu _2 O NPs was found to be 2.26 eV, which is the suitable bandgap energy so as to achieve the enhanced photocatalytic degradation efficiency. On testing for the degradation of Malachite green (MG) as a model pollutant, the synthesized Cu _2 O NPs demonstrated a high degradation efficiency under visible light irradiation. The observed results suggest that the synthesized Cu _2 O NPs are attractive photocatalysts for the degradation of toxic organic wastes in the water under visible light. Further investigation confirmed for the photocatalytic reduction of 4-nitrophenol (4-NP) into 4-aminophenol (4-AP) under aqueous conditions with visible light.