The shock impact of toxic pollutants in petrochemical wastewater on the activated sludge in biological treatment system is a key factor restricting the treatment efficiency. It is necessary to evaluate the toxicity of...
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The shock impact of toxic pollutants in petrochemical wastewater on the activated sludge in biological treatment system is a key factor restricting the treatment efficiency. It is necessary to evaluate the toxicity of these pollutants by appropriate methods. In this study, four test methods were used to evaluate the toxicity of characteristic organic pollutants in petrochemical wastewater including 2,4-dichlorophenol, formaldehyde and pyridine, as well as one frequently-used reference toxicant 3,5-dichlorophenol. The sensitivity, accuracy and response time were compared among these methods: the oxygen consumption rate inhibition method (OCRIM), the dehydrogenase activity inhibition method (DAIM), the nitrification rate inhibition method (NRIM) and the growth rate inhibition method (GRIM). Principal component analysis was used to evaluate the correlation among the results of different methods. The OCRIM was comprehensively outstanding with the highest correlation between concentration and inhibition ratio (R-2 values were all higher than 0.9854), good sensitivity, best accuracy (error value of the effective concentrations below 0.15 mg/l) and fastest response (<40 min). The sensitivity of the NRIM was found to be the highest in this study (10% effective inhibition concentration (EC50) value of 3,5-dichlorophenol was only 0.03 mg/l). Therefore, combined tests of OCRIM and NRIM were suggested. (C) 2019 Elsevier B.V. All rights reserved.
The chemical composition and biological activity of Sanghuangporus vaninii solid culture treated by static magnetic field were *** compounds were isolated and purified using ultrasonic extraction and semi-preparative ...
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The chemical composition and biological activity of Sanghuangporus vaninii solid culture treated by static magnetic field were *** compounds were isolated and purified using ultrasonic extraction and semi-preparative liquid *** structures were identified through spectral data,and the inhibitory activities againstα-amylase,α-glucosidase and pancreatic lipase were *** compounds,5,7-dihydroxy-3,4'-dimethoxyflavone(1),D-(+)-Trehalose(2),pinolenic acid(3),were extracted from the petroleum ether *** of peak heights indicated a significantly higher content of compounds subjected to a 4 mT static magnetic field compared to those *** tests revealed that compounds 1 and 2 exhibited strong anti-α-amylase and anti-α-glucosidase ***,compound 1 had inhibition rates of(65.37±0.05)%and(73.81±0.12)%after 4 mT treatment,compared to(57.26±0.11)%and(65.33±0.14)%*** 2 showed inhibition rates of(68.61±0.12)%and(65.38±0.09)%with the magnetic field,versus(60.71±0.06)%and(56.18±0.02)%*** 3 displayed a notable inhibitory effect on pancreatic lipase,with rates of(60.83±0.03)%after 4 mT treatment and(53.77±0.09)%*** study demonstrates that the static magnetic field enhances the chemical content and bioactivity of Sanghuangporus vaninii solid culture,providing a basis for its further development and application.
Inspired by the features of both transition metal oxide and natural clinoptilolite (flaky structure with suitable pore diameter and open skeleton structure), we adopted a robust strategy by immobilization of nickel fe...
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Inspired by the features of both transition metal oxide and natural clinoptilolite (flaky structure with suitable pore diameter and open skeleton structure), we adopted a robust strategy by immobilization of nickel ferrite nanoparticles (NiFe2O4) on the clinoptilolite surface via typical citric acid combustion method. The hybrid catalyst exhibited enhanced peroxymonosulfate (PMS) activation efficiency and bisphenol A (BPA) degradation performance. Calculated by effective equivalent of NiFe2O4, it is found that the reaction rate constant (k) of NiFe2O4/clinoptilolite/PMS system (0.1859 min(-1)) was 11.9 times higher than that of bare NiFe2O4/PMS system (0.0156 min(-1)), which demonstrated that catalyst would be conjugated to PMS or contaminant efficiently and renders the rapid degradation and mineralization in the presence of clinoptilolite. After comprehensive characterization analysis and DFT simulations, natural mineral carrier effect (i.e. decreased crystalline size, increased oxygen vacancy content, etc.), abundant surface-bonded and structural hydroxyl groups as well as effective bonding with iron or nickel ions charged for the potential activation mechanism of PMS by NiFe2O4/clinoptilolite composite. And it is indicated that not only center dot OH and SO4 center dot, but also O-1(2) was involved into series reactions. Overall, this study put forward a green and promising technology for high-toxic wastewater treatment.
Recently, the graph convolutional networks based methods have achieved remarkable performance in skeleton-based action recognition. However, current methods do not make full use of the topology of the skeleton graph, ...
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ISBN:
(纸本)9781538662496
Recently, the graph convolutional networks based methods have achieved remarkable performance in skeleton-based action recognition. However, current methods do not make full use of the topology of the skeleton graph, because they set and fixed the relation of skeleton joints or adjacency matrix for all input samples manually. In order to solve the problem, we design an end-to-end architecture consisting of joints relation inference network (JRIN) and skeleton graph convolutional network (SGCN). JRIN can aggregate spatial-temporal feature of every two joints globally, then infer the optimal relation between every two joints automatically. These relations of joints is quantified as the optimal adjacency matrices. Then SGCN will take the optimal matrices to do the final action recognition. During training, special initialization and alternate training strategies are proposed to optimize the model. Our method achieves very competitive performance on widely used NTU-RGB+D and Kinetics datasets.
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