Magnussenkirkeby3796

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In this investigation, Ag@AgCl nanoparticles were synthesized by a green and inexpensive method using Elaeagnus angustifolia leaves, as a reducing and stabilizing agent without using any toxic solvent, external halide source, harsh chemicals, or capping agents. In this protocol, the nanophotocatalyst was synthesized via immobilization of Ag@AgCl NPs on the surface of biowaste Elaeagnus angustifolia seed (EAS) as a green support, which prevents the agglomeration Ag@AgCl NPs and improves the catalytic activity. The biosynthesized nanophotocatalyst were characterized by UV-Vis spectroscopy, Fourier transform-infrared spectroscopy (FT-IR), X-ray diffraction (XRD), field emission scanning electron microscopy (FE SEM), energy dispersive X-ray spectroscopy (EDS), and transform electron microscopy (TEM) and inductively couple plasma mass spectrometry (ICP). In order to investigate the photocatalytic activity of the biosynthesized nanophotocatalyst, it was used in the degradation of methylene blue (MB) under sunlight. The results showed that nanophotocatalyst had an excellent photo activity without any agglomeration. In addition, the nanophotocatalyst can be easily be recycled and reused several times without losing its activity. Graphical abstract.Traditional Fenton reagents are less effective for industrial wastewater treatment because they are active in a narrow pH range, precipitate and become inactive, and are difficult to recover. In this study, a heterogeneous Fenton catalyst, γ-Cu-Ce-Al2O3, was prepared by the sol-gel method and evaluated for the treatment of phenol-containing water. The optimal mix of γ-Cu-Ce-Al2O3 includes a Cu content of 5 wt% and a molar ratio between Cu and Ce of 21. The catalyst was prepared by continuously stirring the solution for 24 h and heating to 550 °C for 6 h. The Fenton catalyst was tested with hydrogen peroxide for phenol degradation. An initial phenol concentration of 100 mg/L was removed with 95% efficiency. Additionally, the catalyst was demonstrated to be effective for reuse up to five times with an overall removal rate of 72.3%. The test conditions were based on a catalyst dosage of 1.6 g/L, a hydrogen peroxide dosage of 200 mmol/L, a reaction temperature of 40 °C, an initial pH of 7.0 ± 0.05, and a reaction time of 120 min.Among ex situ remediation technologies, stabilization/solidification (S/S) provides for the addition of a binder to dredged materials in order to chemically immobilise the contaminants and improve mechanical behaviour of sediments. The simplest form of treatment is obtained by the addition of Portland cement or lime (calcium oxide), although other additives such as adsorbents may be added. Nevertheless, the success of the S/S treatment may be affected by the contaminants present or by the salt content in the water. In this study, experimental laboratory investigation was carried out on sediments carefully collected from the Mar Piccolo of Taranto in Southern Italy, contaminated by heavy metals, polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs); the goal was to explore the effectiveness of S/S treatment by using Portland cement/lime as binders, monitoring over time (28 days) the leaching of the different mixtures of treated sediment. It is noted that the Mar Piccolo of Taranto is one of the sites of national interest subject to remediation by the Italian government. Once taken within the first meter under the sea floor by a team of experienced divers, the samples were stored at a controlled temperature, characterised in terms of grain size and physical-chemical characteristics and treated by S/S laboratory tests. The results indicate that the addition of binders increased the pH of the mixtures with a consequent leachability of different metals. The mobility of the metals appeared to be governed also by the curing time. The performance of the mixtures in terms of immobilised metals was influenced by the presence of organic contaminants (e.g. selleck organic matter, PAHs and PCBs). As a lesson, high organic matter and fine-grained particles can negatively affect the effectiveness of the S/S treatment in terms of metal immobilisation.Side issues of economy development break out in China during recent decades, like environmental pollution or the widely ignored one, shadow economy. Using annual data for the three provinces at northeast China over the period 2000 to 2016, this paper examines the size of the shadow economy by MIMIC model first and then adopts the dynamic panel analysis to study the direct relationship between the shadow economy and pollution level. The major innovation point of this paper is the pioneering study of the impact from the pollution level on the size of shadow economy. We also employ various pollution descriptions from terrestrial, aquatic, and atmospheric ecosystems as the robustness check to make our following conclusions more comprehensive and credible (1) shadow economy is a direct quality factor to the increase of the pollution level. (2) A positive effect from pollution to shadow economy also exists the higher the pollution level is, the larger the size of shadow economy will be. In the end, this paper proposes several valuable information and suggestions to the government in economy development and pollution abatement.Conductivity is a very reliable, sensitive, and easily obtained indicator of surface water conditions; however, whether it could be used to evaluate lake pollution is less understood. To verify the effectiveness of using conductivity to evaluate the pollution status in lakes, Lake Taihu was analyzed, the third largest freshwater lake in China, which provides drinking water to about 10 million of residents. We analyzed 25-year conductivity data in 32 sampling sites in Lake Taihu, in relation to human population, industrial development, and GDP. The results showed that the conductivity first increased and then decreased following rapid economic growth and subsequent strict pollution control activities. The conductivity is related to industrial sewage (r = 0.90); SO42- and Cl- concentrations in the water were closely related to the industrial production value (r = 0.98, 0.99) before 2007. The conductivity increased rapidly from 1992 to 2007 due to eutrophication processes. After 2007, with the implementation of various pollution control measures, the pollution situation gradually abated.