Treatment of bisphenol pollutant in water by N,P-co-doped carbon nanosheet: Fast degradation, toxicity elimination and reaction mechanism investigation.

Metal-free carbon catalysts perform well in peroxymonosulfate-based advanced oxidation process for the treatment of organic pollutant-containing wastewater. Herein, a natural biomolecule of adenosine triphosphate (ATP), containing abundant N and P elements, served as sole precursor to prepare N,P-co-doped carbon through one-step anoxic pyrolysis, which was applied as peroxymonosulfate activator to treat bisphenol-contaminated water. Owing to the endogenous N and P elements in ATP, in-situ doping was achieved for the prepared carbon material with excellent doping effect, such as high doping amount and numerous defects. During pyrolysis process, the generated gases facilitated the exfoliation of carbon structure, resulting in a nanosheet-like morphology with large specific surface area, e.g., 852.75 m2 g-1 for NPCN-900 sample obtained at 900 °C. Benefiting from the structural modulation brought by N,P co-doping, typical sample of NPCN-900 presented excellent catalytic performance towards bisphenol AF (BPAF) degradation through PMS activation. An apparent reaction rate constant of 0.4115 min-1 was calculated under the investigated reaction conditions. Further studies indicated that 1O2, surface-bound •OH and SO4-• worked together in NPCN-900/PMS system for BPAF degradation. Graphitic N, pyrrolic N, CO groups, defect structure and the doped P atoms in NPCN-900 contributed to PMS activation. It was also important that the toxicity of BPAF solution could be preliminarily eliminated after treatment by NPCN-900/PMS system, which was verified by ecotoxicity assessments through ECOSAR program and green algae growth experiments.

[Characteristics of nutrient accumulation and vertical spatial distribution in Cunninghamia lanceolata plantation with different stand densities]. / ä¸åŒæž—åˆ†å¯†åº¦æ‰æœ¨æž—å »åˆ†ç§¯ç´¯ä¸Žåž‚ç›´ç©ºé—´åˆ†é .

The growth, biomass, nutrient content and accumulation as well as the vertical distribution of nutrient accumulation in Cunninghamia lanceolata plantation across densities of 1800, 3000, 4500 trees·hm-2 were stu-died in order to provide scientific basis for efficient cultivation of C. lanceolata plantation. The total amounts of nutrients accumulated in C. lanceolata plantation with 1800, 3000, 4500 trees·hm-2 were 1311.57, 2531.55 and 2307.33 kg·hm-2, respectively. There were significant variations among different densities. Under the same density, the order of nutrient content and accumulation in C. lanceolata plantation was total N > total K > total Ca > total Mg > total P. Moreover, the amount of nutrients in trunk and bark decreased with the increases of tree height. The amount of nutrient accumulation in persistent withered branch and leaf were allocated from middle to the upper part of tree, while the opposite was observed for fresh branch and leaf. N accumulation increased with the increases of stand densities, while the other nutrients first increased then decreased. The order of the amount of nutrient accumulation in trunk, bark, root, persistent withered branch, persistent withered leaf and litter among different densities was 4500 > 3000 > 1800 trees·hm-2, and was 3000 > 1800 > 4500 trees·hm-2 in fresh branch and leaf, and 1800 > 3000 > 4500 trees·hm-2 in understory. Under the densities of 1800 and 4500 trees·hm-2, the nutrient distribution ratio in bark was the largest, accounting for 21.6% and 19.4%. In 3000 trees·hm-2, the distribution ratio of fresh leaves reached its maximum, accounting for about 22.9%, and the next was fresh branches, which had a distribution ratio of about 17.8%. 3000 trees·hm-2 was the most appropriate density for nutrient accumulation and distribution in C. lanceolata plantation.

Association of Thyroid Function With the Estimated Glomerular Filtration Rate in a Large Chinese Euthyroid Population.

BACKGROUND/AIMS: We aimed to explore whether thyroid function within a normal range is associated with the estimated glomerular filtration rate (eGFR) and the incidence of chronic kidney disease (CKD) in a large Chinese population. METHODS: We conducted a cross-sectional study that included 10,859 euthyroid individuals who underwent an annual regular health checkup in Jiangsu Province Official Hospital between August 2012 and August 2013. We measured the thyroid-stimulating hormone (TSH), free triiodothyronine (FT3) and free thyroxine (FT4) levels using a Roche modular analytics E170 and then calculated the eGFR using the Chinese modified Modification of Diet in Renal Disease (CMDRD) equation. RESULTS: In multiple linear regression models, TSH was negatively associated with eGFR after adjusting for confounding factors (ß = -0.072, P = 1.994×10-22). The significance remained in both males and females. No significant association was observed between FT4 and eGFR. In the logistic regression model, we did not observe significant associations of TSH or FT3 with CKD. Participants in the highest quartile of FT4 versus the lowest quartile (reference) had an increased risk of CKD (OR = 1.763, P = 0.012). The risk of CKD was more pronounced in females with the highest quartile of FT4 (OR = 2.424, P = 0.029). CONCLUSION: Our findings suggest that TSH is associated with eGFR in euthyroid individuals and that higher FT4 is associated with an increased risk of CKD. More cohort studies are warranted to confirm whether the association is causal.