This research explored the use of homogeneous SUS 304 L stainless steel as both anode and cathode in an electrochemical cell for Photo-Fenton degradation of organic contaminant in water. In order to ...obtain the optimal anodization condition for methyl orange (MO) degradation with the catalysts, the voltage ranged of between 30 V and to 50 V and the anodization time ranged of from 20 min to 30 min were experimented. The anodization process was optimized at 50 V for 20 min, resulting in enhanced MO degradation. The presence of nanopores and oxide layers, mainly γ-Fe2O3 and Cr2O3, on the anodized surfaces were confirmed by various characterizations methods such as field emission electron microscopy (FE-SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), fourier-transform (FTIR) and raman spectroscopy analyses. The anodized stainless steel electrodes demonstrated superior reusability and efficiency under acidic conditions. When compared with platinum electrodes, SUS 304 L stainless steel did not show a difference in degradation efficiency, indicating the potential for economic benefits. This research highlights the potential applications of SUS 304 L stainless steel as a catalyst for the photo-Fenton and cost-effective alternative for platinum cathode in anodization.
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•Anodization using SUS 304 L as a replacement for Pt at the cathode was conducted.•Optimal anodization conditions are identified, enhancing MO degradation.•Nanopores and oxide layers on anodized surfaces were confirmed.•Catalyst performance tested in various pH, suitable for environmental use.
Sustainable development and the restoration of ecosystems are the important goals for civilization. Currently, heavy metal contamination of aquatic environments has become a serious issue. Chromium ...(Cr) is simultaneously an essential metallic element and one of 20 chemicals posing a maximum threat to living beings. To mitigate that threat, various treatment methods have been developed, including adsorption, electrocoagulation, photoelectrocatalysis, fuel cells, bioremediation, chemical precipitation, ultrafiltration, ion exchange, and co-precipitation. However, selection of the most energy- and cost-efficient wastewater treatment option has proven challenging, as each approach is subject to shortcomings involving energy consumption, treatment capacity, and efficiency. This review describes the potential role of diverse functional nanomaterials (e.g., iron/iron oxide nanoparticles, carbon nanostructures, metal organic frameworks, and their commercial counterparts) in treatment of Cr in aqueous environments with respect to key figure of merits, such as, adsorption capacity, removal efficiency, and partition coefficient. In addition, their performance was compared with the most common treatment options. The results of this study will help determine the most effective and economical options for control of Cr in aquatic environments.
•To date, contamination of heavy metals like Cr in aquatic environments has become a serious issue.•To help mitigate Cr pollution, the potential of diverse functional nanomaterials has been assessed.•Their performance has been evaluated with respect to key figure of merits such partition coefficient.•This review will help determine effective/economical options for the control of Cr in water.
Sphingolipids are important structural components of cell membranes and act as critical regulators of cell function by modulating intracellular signaling pathways. Specific sphingolipids, such as ...ceramide, glucosylceramide, and ganglioside GM3, have been implicated in various aspects of insulin resistance, because they have been shown to modify several steps in the insulin signaling pathway, such as phosphorylation of either protein kinase B (Akt) or of the insulin receptor. We now explore the role of the ceramide acyl chain length in insulin signaling by using a ceramide synthase 2 (CerS2) null mouse, which is unable to synthesize very long acyl chain (C22‐C24) ceramides. CerS2 null mice exhibited glucose intolerance despite normal insulin secretion from the pancreas. Both insulin receptor and Akt phosphorylation were abrogated in liver, but not in adipose tissue or in skeletal muscle. The lack of insulin receptor phosphorylation in liver correlated with its inability to translocate into detergent‐resistant membranes (DRMs). Moreover, DRMs in CerS2 null mice displayed properties significantly different from those in wild‐type mice, suggesting that the altered sphingolipid acyl chain length directly affects insulin receptor translocation and subsequent signaling. Conclusion: We conclude that the sphingolipid acyl chain composition of liver regulates insulin signaling by modifying insulin receptor translocation into membrane microdomains. (HEPATOLOGY 2013)
The endoplasmic reticulum (ER) is not only important for protein synthesis and folding but is also crucial for lipid synthesis and metabolism. In the current study, we demonstrate an important role ...of ceramide synthases (CerS) in ER stress and NAFLD progression. Ceramide is important in sphingolipid metabolism, and its acyl chain length is determined by a family of six CerS in mammals. CerS2 generates C22-C24 ceramides, and CerS5 or CerS6 produces C16 ceramide. To gain insight into the role of CerS in NAFLD, we used a high-fat diet (HFD)-induced NAFLD mouse model. Decreased levels of CerS2 and increased levels of CerS6 were observed in the steatotic livers of mice fed a HFD. In vitro experiments with Hep3B cells indicated the protective role of CerS2 and the detrimental role of CerS6 in the ER stress response induced by palmitate treatment. In particular, CerS6 overexpression increased sterol regulatory element-binding protein-1 (SREBP-1) cleavage with decreased levels of INSIG-1, leading to increased lipogenesis. Blocking ER stress abrogated the detrimental effects of CerS6 on palmitate-induced SREBP-1 cleavage. In accordance with the protective role of CerS2 in the palmitate-induced ER stress response, CerS2 knockdown enhanced ER stress and SREBP-1 cleavage, and CerS2 heterozygote livers exhibited a stronger ER stress response and higher triglyceride levels following HFD. Finally, treatment with a low dose of bortezomib increased hepatic CerS2 expression and protected the development of NAFLD following HFD. These results indicate that CerS and its derivatives impact hepatic ER stress and lipogenesis differently and might be therapeutic targets for NAFLD.
The development of efficient adsorbents for the practical recovery of precious metals from electronic waste is vital to advanced energy/environment industries. Ti3C2Tx MXene‐based materials are ...promising adsorbents for aqueous environments; however, the highly defective and super hydrophilic nature of the MXene surface hinders its practical applications. Here, we report that nitrogen‐doped MXene (N‐MXene) nanosheet stacks, prepared via high‐energy planetary ball milling under N2 purging, exhibited a long‐term stable and excellent recovery capability for Au and Ag ions via the nitrogenation of defective vacancies. Notably, these microscale nanosheets could facilitate the sustainable production of Au and Ag from secondary sources, exhibiting a high recovery rate and capability (1198 mg g−1 for Au and 1528 mg g−1 for Ag), long‐term stable storability (21 d), and high selectivity (Kd of 1.67 × 106 for Au and 2.07 × 107 for Ag). Furthermore, the reversible redox chemistry of N‐MXene facilitated its repeated use in adsorption/desorption cycles.
We describe an N‐doped MXene nanosheet stack produced by a high‐energy planetary ball milling under N2‐purged conditions. This process effectively stabilizes defective vacancies of MXene nanosheets while forming a macroscale MXene nanosheet stack, making it easy to recover after use in the aqueous environments. MXene nanosheet stack shows its long‐term storability, selective and efficient precious metal recovery capability, and reusability.
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Titanium dioxide (TiO2)-cadmium sulfide (CdS) hybrid nanoparticles on magnetic-cored dendrimers (MCDs) of the zero and first generations (G0 and G1, respectively) were synthesized ...under hydrothermal conditions. TiO2 was embedded with CdS to produce more radicals and suppress the recombination of photo-induced electrons and holes. A dendrimer with a magnetite core was used as a template to immobilize the TiO2/CdS nanocomposites. They were characterized via scanning electron microscopy, transmission electron microscopy, and X-ray diffraction. The obtained G0- and G1-MCD-TiO2/CdS exhibited high photocatalytic activity and was able to degrade methyl orange (MO) by 83.6 and 88.5%, respectively, in 120 min under ultraviolet irradiation. After 5 cycles, the MO degradation by G0- and G1-MCD-TiO2/CdS was 78.8 and 81.4%, respectively. The MCD-TiO2/CdS materials were easily recycled by applying an external magnetic field. G0-TiO2/CdS was more efficient in photocatalytic performance than G1-TiO2/CdS. Apparent quantum yields (AQYs) and figures of merit (FOMs) were calculated to quantify the photocatalytic performance. The AQYs of G0- and G1-MCD-TiO2/CdS were 3.48 × 10−5 and 3.69 × 10−5 molecules photon−1, respectively. The FOM of our proposed materials demonstrated its high capability for photocatalytic degradation of MO.
We demonstrate high-performance polymer solar cells using the plasmonic effect of multipositional silica-coated silver nanoparticles. The location of the nanoparticles is critical for increasing ...light absorption and scattering via enhanced electric field distribution. The device incorporating nanoparticles between the hole transport layer and the active layer achieves a power conversion efficiency of 8.92% with an external quantum efficiency of 81.5%. These device efficiencies are the highest values reported to date for plasmonic polymer solar cells using metal nanoparticles.
Background and aims Biochar has attracted research interest due to its ability to increase the soil carbon pool and improve crop productivity. The objective of this study was to evaluate the metal ...immobilizing impact of chicken manure- and green waste-derived biochars, and their effectiveness in promoting plant growth. Methods The immobilization and phytoavailability of Cd, Cu and Pb was examined using naturally contaminated shooting range and spiked soils. Biochar samples prepared from chicken manure and green waste were used as soil amendments. Results Application of biochar significantly reduced NH4NO3 extractable Cd, Cu and Pb concentrations of soils, indicating the immobilization of these metals. Chicken manure-derived biochar increased plant dry biomass by 353 and 572% for shoot and root, respectively with 1% of biochar addition. This might be attributed to reduced toxicity of metals and increased availability of nutrients such as P and K. Both biochars significantly reduced Cd, Cu and Pb accumulation by Indian mustard (Brassica juncea), and the reduction increased with increasing amount of biochar application except Cu concentration. Metal sequential fractionation data indicated that biochar treatments substantially modified the partitioning of Cd, Cu and Pb from the easily exchangeable phase to less bioavailable organic bound fraction. Conclusions The results clearly showed that biochar application was effective in metal immobilization, thereby reducing the bioavailability and phytotoxicity of heavy metals.
Poly(vinylidene fluoride) (PVDF) is common polymer for electrospinning, however, its high hydrophobicity is a major drawback, which cause fouling. To introduce hydrophilicity and antibacterial ...activity, quaternary ammonium-functionalized amphiphilic diblock copolymers were synthesized and blended with a PVDF/graphene oxide (GO) solution, then, electrospun and coated with a hydrophilic polymer, poly(vinyl alcohol) (PVA). The amphiphilic block copolymer, consisting of a hydrophobic poly(methyl methacrylate) block and a hydrophilic polyN,N-2-(dimethylamino)-ethyl methacrylate) block (PMMA-b-PDMAEMA), was synthesized. Polymeric quaternary ammonium with three different alkyl chain lengths (C
, C
, and C
) were successfully introduced to obtain as q-PMMA-b-PDMAEMA. The q-PMMA-b-PDMAEMA in the nanofiber matrix was confirmed by C=O bands (1734 cm
) in the Fourier transform infrared spectra. Nano-sized spherical protuberances were distributed on the surface as revealed by field emission scanning and transmission electron microscopies. The PVDF/GO/q-PMMA-b-PDMAEMA@PVA nanofibers has superhydrophilic properties (water contact angle = 0-20°) and the pure water flux was generally improved by increasing the alkyl chain length. When introducing the longest alkyl chain (C
), the total fouling ratio was the lowest (49.99%) and the bacteria removal capacities after 60 min were the highest for both Escherichia coli (4.2 × 10
CFU/mg) and Staphylococcus aureus (6.1 × 10
CFU/mg) via growth inhibition and cytoplasmic membrane damage.
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