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Detection levels were then determined for PVC and PS and were found to be below less then 50 μg/L, with repeatable data showing good precision (%RSD less then 20%). Further verification of this new method was achieved by the analysis of a complex sample, sourced from a river. The results were positive for the presence of PS with a semi-quantifiable result of 241.8 μg/L. Therefore PY-GCToF seems to be a fit for purpose method for the identification of MPs and NPs from complex mixtures and matrices which have been deposited on PTFE membranes. In this study, a simple sol-gel method was applied for preparing effectual photocatalyst of S-Bi co-doped F-TiO2/SiO2 (S-Bi-F-TiO2/SiO2) nanopowder. Optimal preparation conditions were obtained by optimizing the calcination temperature and the ratio of S and Bi. The synthesized powder was characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), energy dispersive spectrometer (EDS), X-ray photoelectron spectroscopy (XPS), brunauer-emmett-teller (BET), UV-Visible diffuse-reflectance spectroscopy (UV-Vis DRS), photoluminescence spectroscopy (PL) and ammonia adsorption and temperature-programmed desorption (NH3-TPD). The photocatalytic activity was evaluated by the degradation of acrylonitrile under simulated visible light irradiation. S-Bi-F-TiO2/SiO2 nanopowder possess excellent photocatalytic properties under visible light for the degradation of acrylonitrile, when the calcination temperature was 450 °C for 2 h and the ratio of S and Bi was 0.02 0.007. The degradation efficiency of acrylonitrile reached to 81.9% within 6 min of visible light irradiation. Compared with F-TiO2/SiO2 sample, NH3-TPD and PL results revealed the higher photocatalytic activity for S-Bi-F-TiO2/SiO2, which is mainly due to the increase strength and number of surface acid site with S doping. The co-doping with S & Bi improved the separation of electron-hole pairs and enhanced the photocatalytic oxidizing species. The UV-Vis DRS showed stronger absorption in S-Bi co-doped F-TiO2/SiO2 catalyst as compared to F-TiO2/SiO2 catalyst. XPS results demonstrated the presence of various surface species viz. oxygen vacancies, Ti3+, Ti4+, O2- and OH group. The performance, microbial community and enzymatic activity of activated sludge from four identical sequencing batch reactors (SBRs) were compared by treating synthetic wastewater under the single and combined divalent copper (Cu2+) at 20 mg/L and humic acid (HA) at 20 mg/L. Compared with the absence of Cu2+ and HA, the single HA slightly enhanced the oxygen uptake rate (OUR), the nitrification and denitrification rates and the activities of dehydrogenase, nitrifying enzymes and denitrifying enzymes, whereas the single Cu2+ had the opposite results. The combined Cu2+ and HA inhibited the OUR, nitrogen removal rate and enzymatic activity of activated sludge almost the same as the single Cu2+. The single HA had no obvious effect on the balance between the microbial oxidative stress and antioxidant activity. However, the variations of microbial reactive oxygen species production, peroxidase activity, catalase activity, superoxide dismutase activity, and lactate dehydrogenase release demonstrated that the combined Cu2+ and HA and single Cu2+ produced obvious toxicity to microorganisms in activated sludge. The microbial richness and diversity had some obvious changes under the single and combined Cu2+ and HA. Nicotinamide Riboside The relative abundances of Nitrosomonas, Nitrospira and some denitrifying genera (e.g. Zoogloea, Dokdonella, Denitratisoma, Flavobacterium and Thermomonas) under the combined Cu2+ and HA were less than those under the single Cu2+. Benz(a)anthracene (BaA) is a polycyclic aromatic hydrocarbons (PAHs), that belongs to a group of carcinogenic and mutagenic persistent organic pollutants found in a variety of ecological habitats. In this study, the efficient biodegradation of BaA by a green alga Chlamydomonas reinhardtii (C. reinhardtii) CC-503 was investigated. The results showed that the growth of C. reinhardtii was hardly affected with an initial concentration of 10 mg/L, but was inhibited significantly under higher concentrations of BaA (>30 mg/L) (p  less then  0.05). We demonstrated that the relatively high concentration of 10 mg/L BaA was degraded completely in 11 days, which indicated that C. reinhardtii had an efficient degradation system. During the degradation, the intermediate metabolites were determined to be isomeric phenanthrene or anthracene, 2,6-diisopropylnaphthalene, 1,3-diisopropylnaphthalene, 1,7-diisopropylnaphthalene, and cyclohexanol. The enzymes involved in the degradation included the homogentisate 1,2-dioxygenase (HGD), the carboxymethylenebutenolidase, the ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco) and the ubiquinol oxidase. The respective genes encoding these proteins were significantly up-regulated ranging from 3.17 fold to 13.03 fold and the activity of enzymes, such as HGD and Rubisco, was significantly induced up to 4.53 and 1.46 fold (p  less then  0.05), during the BaA metabolism. This efficient degradation ability suggests that the green alga C. reinhardtii CC-503 may be a sustainable candidate for PAHs remediation. An adverse tendency induced by the environmental estrogens in female reproductive health is one serious problem worldwide. Diethylstilbestrol (DES), as a synthetic estrogen, is still used as an animal growth stimulant in terrestrial livestock and aquaculture illegally. It has been reported to negatively affect ovarian function and oogenesis. Nevertheless, the mechanism and toxicity of DES on oocyte meiotic maturation are largely unknown. Herein, we found that DES (40 μM) intervened in mouse oocyte maturation and first polar body extrusion (PBE) was decreased in vitro. Cell cycle analysis showed meiotic process was disturbed with oocytes arrested at metaphase I (MI) stage after DES exposure. Further study showed that DES exposure disrupted the spindle assembly and chromosome alignment, which then continuously provoke the spindle assemble checkpoint (SAC). We also observed that the acetylation levels of α-tubulin were dramatically increased in DES-treated oocytes. In addition, the dynamics of actin were also affected.

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