Aaenvazquez5702

Z Iurium Wiki

To the best of our knowledge, the present study was pioneer in reporting PE MPs-induced behavioral toxicity in representatives of amphibian groups. The activation rate of oxygen by zero-valent iron (Fe°) was very low. In this study, ethylenediaminetetraacetic acid (EDTA), oxalate (Ox), and phosphate ions (Na2HPO4) were used to enhance the oxygen activation by Fe° for sulfamethazine (SMT) removal. The addition of these ligands could significantly enhance the SMT degradation. Bufalin manufacturer SMT removal was improved from 10.5 % in the Fe° system (360 min) to 70.3 %, 85.2 % and 77.8 % in the Fe°/EDTA (60 min), Fe°/Ox (180 min) and Fe°/phosphate (360 min) systems, respectively. Scanning electron microscopy with energy dispersive X-ray (SEM-EDX), Fourier transform infrared reflection (FTIR), contact angle and X-ray photoelectron spectra (XPS) of Fe° in different systems were recorded. The presence of chelating agents hydroxylated Fe°, inhibited the iron oxide formation on the Fe° surface and promoted iron ion release from the solid. Moreover, the agents improved the recovery of surface Fe2+ which could subsequently enhance the activation of O2 to produce more H2O2 and reactive oxygen radicals for SMT removal. OH radical produced mainly through H2O2 decomposition was primarily responsible for removing SMT in all three systems. The Fe° system added with chelating agents is a new and promising approach for treating wastewaters containing ligands. A novel polymer-based 2D/2D heterojunction photocatalysts of covalent triazine-based frameworks/graphitic carbon nitride nanosheets (CTFNS/CNNS) heterojunction are successfully obtained by an electrostatic self-assembly method using amine-functionalized CNNS and carboxyl-rich CTFNS. Such large contact surface and appropriate interfacial contact between CNNS and CTFNS plays a critical role in transfer and separation of charge-carriers. The resulting CTFNS/CNNS heterojunction showed significantly enhanced photocatalytic activity under the irradiation of simulated solar light, which could decompose 10 ppm sulfamethazine (SMT) within 180 min with a high degradation efficiency of 95.8 %. Chloride ions can greatly promote the photocatalytic degradation of SMT due to the production of more radical species. O2- is the dominant active species for SMT decomposition over CTFNS/CNNS heterojunction. Moreover, the degradation intermediates of SMT were identified using high performance liquid chromatography-mass spectrometer and the degradation pathway was proposed. This study provides a new insight into the design of 2D/2D heterojunctions using carbon-based nanomaterials, which exhibits great potential in the degradation of sulfonamide antibiotics in wastewaters. Straw biochar and straw application to paddy soil dramatically altered arsenic (As) biogeochemical cycling in soil-rice system, but it remains unknown how As biotransformation microbes (ABMs) contribute to these processes. In this study, rice pot experiments combining terminal restriction fragment length polymorphism (T-RFLP) analysis and clone library were performed to characterize ABMs. Through linear discriminant analysis (LDA) effect size (LEfSe) and correlation analysis, results revealed that arrA-harbouring iron-reducing bacteria (e.g., Geobacter and Shewanella) and arsC-harbouring Gammaproteobacteria (e.g., fermentative hydrogen-producing and lignin-degrading microorganisms) potentially mediated arsenate [As(V)] reduction under biochar and straw amendments, respectively. Methanogens and sulfate-reducing bacteria (SRB) carrying arsM gene might regulate methylated As concentration in soil-rice system. Network analysis demonstrated that the association among ABMs in rhizosphere was significantly stronger than that in bulk soil. Arsenite [As(III)] methylators carrying arsM gene exhibited much stronger co-occurrence pattern with arsC-harbouring As(V) reducers than with arrA-harbouring As(V) reducers. This study would broaden our insights for the dramatic variation of As biogeochemical cycling in soil-rice system after straw biochar and straw amendments through the activities of ABMs, which could contribute to the safe rice production and high rice yield in As-contaminated fields. Nanoplastics (NPs) are emerging pollutants which can adsorb large amounts of hydrophobic organic compounds (HOCs) and be ingested by aquatic organisms. NPs interact with dissolved organic matter (DOM) and result in significant impacts on the bioaccumulation of HOCs in the actual environment. For the first time, the joint effects of two complex matrices on the bioaccumulation of polycyclic aromatic hydrocarbons (PAHs) to Daphnia magna (D. magna) were studied by modeling calculation. The complex matrices, nano-sized polystyrene (PS) and/or humic acid (HA), were under environmentally realistic concentrations. A biodynamic model was modified and the uptake fluxes from all exposure pathways were quantified using the experimental data. A flux estimation showed that the bioaccumulation amounts at equilibrium were mostly dependent on dermal uptake (≥99.3 % of the total). The PS matrix would retard the intestinal uptake process in D. magna, especially for the less hydrophobic PAHs; while the HA or the HA-PS matrix would facilitate the mass transfer of PAHs from the matrix to lipids in the gut. Moreover, the biota matrix accumulation factor (BMAF) were calculated to verify the biodynamic model. This work is helpful to clarify the bioaccumulation effects of PAHs in complex environmental systems. The partial oxidation on refractory organics in ozonation process and the poor performance of mass transfer between ozone (O3) phase and liquid phase by common O3 distribution techniques inhibit the practical application of O3. To overcome these defects, hollow fiber membrane was applied in membrane contact ozonation (MCO)-UV process for the reactive brilliant red X-3B (RBRX-3B) degradation. The efficiency of mass transfer was guaranteed due to the enormous gas/liquid contact area supplied in this bubble-less O3 transfer process. UV photolysis not only significantly improved the O3 utilization efficiency but also accelerated the mineralization of RBRX-3B by promoting O3 to decompose to hydroxyl radicals (OH). When 15 mg/L of O3 was supplied at flow rate of 0.2 L/min, and a liquid velocity of 0.453 m/s, the chemical oxygen demand (COD) removal and total organic carbon (TOC) removal reached 90 % and 77 %, respectively. The rate constant for TOC removal in the MCO-UV process (7.89 × 10-3 min-1) was 3.08 and 6.12 times higher than that in MCO and UV photolysis processes, respectively.

Autoři článku: Aaenvazquez5702 (Huff Schulz)