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The toxicity characteristic leaching procedure (TCLP) method was used to analyze the contaminants in the sediment materials of Kaohsiung Harbor as to evaluate the pollution potential associated with the Kaohsiung Harbor. A total of 80 sediment samples were collected at 20 locations and characterized for water content, organic matter (OM), total nitrogen (TN), total phosphorus (TP), and total grease (TG) as well as the leachable and total metals. The results indicated that the leachable metal concentrations were below the low detectable levels for mercury (Hg), lead (Pb), cadmium (Cd), chromium (Cr), and silver (Ag), between 0.005 and 0.281 mg/L, 0.07 and 24.0 mg/L, and 0.013 and 0.221 mg/L for Cu, Zn, and Ni, respectively. The leachable metal concentration at the river mouth vicinity was higher than that at other locations indicating that upstream industrial and domestic wastewater discharges were the main pollutant sources. Results of correlation studies revealed that the OM concentration in the sediment was highly correlated with TN, TP, TG, and total metal as well as the leachable Cu, Zn, and Ni. The above observation indicates that the OM present in the sediment mainly comes from man-made pollutants. All leachable metals in the Kaohsiung Harbor sediment were blown by the US Environmental Protection Administration standard. Hence, the dredged sediment from Kaohsiung Harbor can be a useful sea-filling material for land reclamation; however, the continuing leaching of metals and its impact on the aquatic environment need to be studied further. [ABSTRACT FROM PUBLISHER]

The process of electrochemical oxidation (ECO) of ammonia (NH3) is becoming an increasingly important issue in environmental electrochemistry and has various prospective applications. A copper-based rare earth electrode material was synthesized by co-precipitation of a mixture that included copper, lanthanum, and cerium nitrate salts, and this material was applied in a typical electrocatalytic reaction, such as NH3-ECO, for fuel cell applications. In this study, the ability to oxidize ammonium for ECO while immersed in a 0.5 M H2SO4solution was evaluated using a cyclic voltammetry (CV) technique. The changes in the properties of the electrocatalytic materials were analyzed using UV–vis absorption spectra, fluorescence spectroscopy (FS), and environmental scanning electron microscopy, revealing that the activity of the copper-based rare earth electrode materials utilized a high potential scan rate. The maximum current density was reached when the NH3-ECO voltage was −0.1 V. The reversible redox ability during CV may explain the high activity of the catalysts, suggesting the presence of a synergetic effect between the copper-based composite materials. Additionally, the FS displayed three fluorescence peaks with excitation wavelengths of 265, 450, and 500 nm at room temperature before the reaction. These excitation peaks can be attributed to a metal-enhanced fluorescence effect that is associated with the copper clusters on the electrocatalyst surface during the reaction, proving that FS is an appropriate and effective tool for characterizing the copper clusters that enhance the intrinsic fluorescence characteristics of Cu–La–Ce composite within catalytic treatment systems. When observing the UV–vis absorption spectra for the copper (II) species, the peak absorbance value was at 220 nm. [ABSTRACT FROM PUBLISHER]

The objective of this study is to assess the feasibility of a data mining association analysis technique, the FP Growth algorithm, for the detection of associations of liver cancer, geographic location and demographic of patients. For the research, we are planning to use data extracted from electronic health record systems of three healthcare organizations in different geographic locations (Canada, Taiwan and Mongolia). The data are arranged into 'transactions' which contain a set of data items focused around cancer diseases, geographic locations and patient demographics. This analysis produces association rules that indicate what combinations of demographics, geographic locations and patient characteristics lead to liver cancer. [ABSTRACT FROM AUTHOR]

This work discusses the oxidation of ammonia (NH3) at temperatures between 150 and 400°C (423 and 673 K) by selective catalytic oxidation (SCO) over a nanoarchitectures CuO/CeO2 composite catalyst that was prepared through coprecipitation (CP) method of copper nitrate and cerium nitrate at molar ratio of 7∶3. The catalysts were characterized using thermogravimetric analysis (TGA), BET, analytical scanning transmission electron microscopy (AEM), and cyclic voltammetric (CV) measurement. The experimental results demonstrate that the presence of ammonia was removed around 97% NH3 reduction was achieved during catalytic oxidation over the nanoarchitectures CuO/CeO2 composite catalyst calcine treated at 500°C (773 K) with an oxygen content of 4%. The composite particles were characterized by AEM, with a particle size around nanoscale particle sizes (∼5 nm) with high dispersion phenomena. The nanoarchitectures CuO/CeO2 composite-induced cytotoxicity in the human lung cell line, MRC-5, was tested, and cell survival was determined by 3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetra-zolium (MTS) analysis in vitro. These results indicated that the nanoarchitectures CuO/CeO2 composite catalyst is only weakly cytotoxic to human lung cells. [ABSTRACT FROM AUTHOR]

The article discusses a study related to the application of copper-activated carbon fiber (ACF) catalysts to oxidize aqueous solutions of ammonia in a trickle bed reactor. It notes that ACF substrates have been deposited with copper nitrate. It mentions that ammonia has been removed from effluent streams at liquid space velocity.

Hydrodynamic cavitation (HC) coupled with persulfate (PS)-based that resulted in the synergistic degradation of polycyclic aromatic hydrocarbons (PAHs) in contaminated marine sediments. The effects of HC injection pressure and Σ[PAH]: [PS] on the rate and extent of PAH degradation were studied in the pressure range of 0.5-2.0 bar, PS concentration rage of 2 × 10 -4 to 2 × 10 -2  M or Σ[PAH]: [PS] of 1:10-1000, and reaction time of 20-60 min. A pseudo-first-order rate law fitted PAHs removal kinetics well. The degradation rate constant increased with injection pressure, reaching the maximum level at 0.5 bar, then decreased at injection pressure became greater than 0.5 bar. The results showed that PAH removal was 84% by the combined HC and PS process, whereas, HC alone only achieved a 43% removal of PAHs in marine sediments under the optimal inlet pressure of 0.5 bar at PS concentration of 2 × 10 -2  M in 60 min. The HC‒PS system effectively removed PH, PY, FLU, BaA, and CH at 91, 99, 91, 84, and 90%, respectively. The maximum removal of 6-, 5-, 4-, 3-, and 2-ring PAHs was 89, 87, 84, 76, and 34%, respectively. Major reactive oxygen species (ROSs), namely, SO 4 -• and HO•, were responsible for PAHs degradation. Results clearly highlighted the feasibility of HC-PS system for the clean-up of PAHs-laden sediments in particular and other recalcitrant organic contaminants in general., (Copyright © 2021. Published by Elsevier Ltd.)

The effect of pyrolysis temperature on the generation of polycyclic aromatic hydrocarbons (PAHs) in sewage sludge biochar (SSB) and the removal of hazardous chemicals from esturine sediments by SSB and sodium percarbonate (SPC), exemplified by 4-nonylphenol (4-NP) were studied. SSB synthesized at 500 °C (SSB500) achieved the highest 4-NP degradation efficiency of 73%, at pH 0 9.0 in 12 h of reaction time. The enhanced 4-NP degradation was attributed to the SSB500 activation activation of SPC that produced sufficient •OH and CO 3 -• due to electron-transfer interaction on the Fe-Mn redox pairs. The microbial community diversity and composition of the treated sediment were compared using high-throughput sequencing. Results showed SSB/SPC treatment increased the microbial diversity and richness in the sediments. Proteobacteria were the keystone phylum, while Thioalkalispira genera were responsible for 4-NP degradation in the SSB/SPC treatment. Over all, results revealed the change in the bacterial community during the environmental applications of SSB, which provided essential information for better understanding of the monitoring and improvement of sustainable sediment ecosystems., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Sludge from a groundwater treatment plant was used to prepare biochar by pyrolysis. The Fe-Mn rich biochar was used to activate percarbonate for the remediation of polycyclic aromatic hydrocarbons (PAHs) contaminated aquatic sediments. Results showed that the sludge-derived biochar (SBC) produced at a pyrolysis temperature of 700 °C was the most effective in activating percarbonate, which exhibited significant oxidative removal of PAHs. PAHs degradation took place via a Fenton-like oxidation manners, contributed from the Fe 3+ /Fe 2+ and Mn 3+ /Mn 2+ redox pairs, and achieved the highest degradation efficiency of 87% at pH 0 6.0. Reactions between oxygenated functional groups of biochar and H 2 O 2 generated of O 2 •- and HO• radicals in abundance under neutral and alkaline pH was responsible for the catalytic degradation of PAHs. Our results provided new insights into the environmental applications of SBC for the green sustainable remediation of organics-contaminated sediments and aided in reduction of associated environmental and health risk., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

A poly(l-serine)-modified glassy carbon electrode (PLS/GCE) was fabricated by electropolymerization and used to study the detection of naproxen (NPX), a representative non-steroidal anti-inflammatory drug, in phosphate buffer supporting electrolyte at pH 5.0. Results indicated that the PLS/GCE was capable of determination of NPX at a working potential of 0.92 (vs. Ag/AgCl) in voltammetry mode. Experimental factors such as scan rate, accumulation time, solution pH, initial NPX concentration, and interferences were optimized for NPX determination efficiency. The morphology and elemental distribution of the electrode surface were characterized by ESEM, TEM, PSD, XRD, FTIR, TGA, XPS, and zeta potential. NPX oxidation current increased with increasing analyte concentration and scan rate but decreased with increasing pH. Linear sweep voltammetry calibration curve was established in the NPX concentration range of 4.3-65 μM, with detection limit and average recovery of 0.69 μM (n = 3) and 104 ± 2.5%, respectively. PLS/GCE is simple, accurate, reproducible, and easy for operation, therefore would be cost-effective for the determination of NPX., Competing Interests: Declaration of competing interests The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

4-Nonylphenol (4-NP), a phenolic endocrine disruptor chemical (EDC), is known to have high toxicity to aquatic organisms and humans. The remediation of 4-NP-contaminated marine sediments was studied using red algae-based biochar (RAB) thermochemically synthesized from Agardhiella subulata with simple pyrolysis process under different temperatures of 300-900 °C in CO 2 atmosphere. The RAB was characterized by XRD, Raman, FTIR spectroscopy, and zeta potential measurements. The calcium in RAB efficiently activated sodium percarbonate (SPC) to generate reactive radicals for the catalytic degradation of 4-NP at pH 9.0. The oxygen-containing functional groups reacted with H 2 O 2 , which increased the generation of reactive radicals under alkaline pH condition. Ca 2+ ion was the active species responsible for 4-NP degradation. CaO/CaCO 3 on RAB surface enhanced direct electron transfer, increased HO production, and 4-NP degradation in marine sediments. Langmuir‒Hinshelwood type kinetics well described the 4-NP degradation process. Remediation of contaminated sediments using RAB could be a sustainable approach toward closed-loop biomass cycling in the degradation of 4-NP contaminants., Competing Interests: Declaration of competing interests The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier Ltd. All rights reserved.)