Yusufhaaning8455

In contrast, DON may periodically because for concern in streams subject to high agricultural run-off, likely during certain times of year where cereal crops are susceptible to higher fungal infections rates and may pose increased risks due to climate change.Persistent halogenated compounds (PHC) are of concern for human and environmental health. read more Persistent Organic Pollutants (POPs) are regulated by international treaties, but alternative compounds such as novel brominated flame retardants (NBFRs) and Dechlorane Plus (DP) are not-yet they are increasingly used. There are no data on PHCs in coral reef biota from tropical islands in the western Indian Ocean (WIO). For this assessment, three hard coral genera, two soft coral genera, and ember parrotfish (Scarus rubroviolaceus) were collected from the remote Rodrigues, Agalega, and St. Brandon's Atoll (Republic of Mauritius) in the Mascarene Basin of the WIO. Five compounds - Pentabromotoluene (PBT), γ-HCH, p,p'-DDE, HCB, and BDE-47- were quantifiable in all samples. Hard coral consistently contained the lowest concentrations of PHCs, except for NBFRs. The presence of BDE-47 suggests long-range aerial transport. We quantified DP, currently a candidate POP, in coral reef biota. PBT was measured in all samples also suggests long-range transport. Because the hard coral, soft coral, and fish had differing concentrations and patterns of PHCs, future surveys should stratify sampling accordingly. Agalega and St. Brandon's Atoll can be considered as locations to monitor changes in background concentrations of pollutants due to their remoteness.Compared with traditional photocatalysis system, TiO2 charge carrier generation and interfacial charge-transfer process may be influenced by various chemical and physical effects in underwater pulsed discharge plasma system. Here, the role of high-energy electron, ozone in TiO2 charge carrier generation and transfer process has been investigated using phenol as the probe molecule. The introduction of electron-trapping agent (KH2PO4) have an inhibiting effect on TiO2 catalytic activity, indicating high-energy electrons played a significant role in TiO2 catalytic process. EPR analysis showed that TiO2 could be activated to initiate pairs of electron-hole by high-energy electrons from plasma, and the electrons on the conduction band (CB) could be trapped on the oxygen vacancies. XPS analysis showed that the Ti3+OH species formed during discharge process due to the capture of CB electrons by Ti4+OH groups located at the TiO2 surface. The CB electrons transfer processes on TiO2 surface was strongly dependent on the redox potential of electron acceptors, which adsorbed on the TiO2 surface. The CB electrons can be transferred to dissolved O3, resulting in more OH production. Meanwhile, the CB electron also transferred to benzoquinone adsorbed on TiO2, resulting in accumulation of hydroquinone.Erbium-doped TiO2 nanotubes (Er-TiO2 NTs) are prepared with a combination of anodization and electrochemical deposition using various proportions of erbium and adjusting the time of the process. The surface characterization techniques and electrochemical analysis are applied to study the physicochemical and photoelectrochemical (PEC) properties of the as-prepared photocatalysts. Er-TiO2 NTs have crystal sizes of about 24-30 nm, smaller than those of pure TiO2 NTs, and contain only the anatase phase. Er-TiO2 NTs exhibit an effective photo-conversion efficiency (PCE) of 1.58% and a photosensitivity of 115.06. The modified sample are also more efficient (photocurrent density of 6.64 mAcm-2 at a bias potential of 1.5 V vs. Hg/HgO) compare to pure TiO2 NTs. The photocatalytic activity of the Er-TiO2 NTs are evaluated in a hydrogen generation reaction, and the results show hydrogen production of ∼17.39 μmolhr-1cm-2. Further experiments demonstrate that Er-TiO2 NTs successfully degrade methylene blue, with the most active sample reaching 85% photocatalysis after 180 min. This study shows that doping conditions significantly affect the optical and electrical properties of the resulting material, and that the current electrochemical approach to metal doping can be used for efficient and stable PEC water splitting.In this work, we prepared PU-composites with Australian palm residues (PR) in different contents (5, 10, 15, and 20 wt%) and granulometry (28 and 35 mesh) to improve the oil (crude oil and S500 Diesel) sorption capacity. The foams were characterized by life cycle assessment (LCA), scanning electron microscopy, oil sorption, desorption, and Langmuir, Freundlich, and Temkin sorption isotherms. LCA indicated that higher PR contents decreased the foam environmental impacts than the classical residue handling, indicating that 20 wt% PR is the better environmental option, independent of the residues granulometry. The PR incorporation into PU foams resulted in smaller pore sizes, with a higher number of homogeneous open-cells. The PU composites exhibited higher oil adsorption capacity than the pristine foam. The PU sample showed maximum absorption capability of 6.1 and 6.7 g g-1 for diesel S500 and crude oil, and the composites showed increased values of ∼18 g g-1 and ∼24 g g-1. The Langmuir model presented the best fit and predicted a maximum adsorption capacity of 30.39 and 25.57 g g-1 for PU-20% PR 28 and 35 mesh, respectively. The composites presented excellent reusability with PU-20% PR (28 mesh) and PU-20% PR (35 mesh), showing removal efficiency after 16 and 9 cycles, respectively. The results classify the developed foams as excellent materials to sorb spilled crude oil in marine accidents.Fe(II) is more soluble and bioavailable than Fe(III) species, therefore the investigation of their relative abundance and redox processes is relevant to better assess the supply of bioavailable iron to the ocean and its impact on marine productivity. In this context, we present a discrete chemiluminescence-based method for the determination of Fe(II) in firn matrices. The method was applied on discrete samples from a snow pit collected at Dome C (DC, Antarctica) and on a shallow firn core from the Holtedahlfonna glacier (HDF, Svalbard), providing the first Fe(II) record from both Antarctica and Svalbard. The method showed low detection limits (0.006 ng g-1 for DC and 0.003 ng g-1 for the HDF) and a precision ranging from 3% to 20% RSD. Fe(II) concentrations ranged between the LoD and 0.077 ng g-1 and between the LoD and 0.300 ng g-1 for the Antarctic and Arctic samples, respectively. The Fe(II) contribution with respect to the total dissolved Fe was comparable in both sites accounting, on average, for 5% and 3%, respectively.