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Unlined iron pipe (UIP) is still widely in use in drinking water distribution systems (DWDS), discoloration easily happens after a long-time retention due to iron release, but the influence of initial chlorine on water quality under this condition is not clear. Here, we studied the water quality changes in UIP section reactors under different initial chlorine dosages. Results showed that chlorine could disappeared rapidly within 0.5 h in the UIP. The water with higher initial chlorine (5 mg/L) had higher turbidity in a short time (within 1.5 h), but for a longer retention time (2∼12 h), the highest turbidity was in the iron pipe without initial chlorine. Interestingly, a clear increase in adenosine triphosphate in the UIPs was observed with the increase of initial chlorine, which was in accordance with the results of heterotrophic plate count. Polysaccharide and protein increased with the increase of initial chlorine, which would benefit the formation of a protective layer to inhibit corrosion. This study reflects that during the overnight retention in UIP, raising chlorine would be effective to control discoloration, but chemical and microbiological risks may increase.
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http://dx.doi.org/10.1016/j.watres.2022.119146 | DOI Listing |
Chem Commun (Camb)
September 2025
School of Chemistry and Life Resources, Renmin University of China, Beijing, 100872, China.
Through molecular dynamics simulations of imidazolium-based ionic liquid-water mixtures, it was found that the trace water leads to an anomalous non-monotonic change in the diffusion coefficients of ionic liquid, characterized by an initial decrease followed by an increase. Hydrogen bond analysis revealed that this unusual trend is governed by the weighted hydrogen bond lifetime, reflecting the stability of the hydrogen-bond network, rather than simply the number or energy of hydrogen bonds.
View Article and Find Full Text PDFJ Am Chem Soc
September 2025
State Key Laboratory of Chemistry for NBC Hazards Protection, College of Chemistry, Fuzhou University, Fuzhou 350116, P. R. China.
The activation of methane and other gaseous hydrocarbons at low temperature remains a substantial challenge for the chemistry community. Here, we report an anaerobic photosystem based on crystalline borocarbonitride (BCN) supported Fe-O nanoclusters, which can selectively functionalize C-H bonds of methane, ethane, and higher alkanes to value-added organic chemicals at 12 °C. Scanning transmission electron microscopy and X-ray absorption spectroscopy corroborated the ultrafine FeOOH and FeO species in Fe-O clusters, which enhanced the interfacial charge transfer/separation of BCN as well as the chemisorption of methane.
View Article and Find Full Text PDFEnviron Sci Technol
September 2025
Solar Energy Research Centre (CIESOL), Joint Centre of the University of Almería-CIEMAT, Carretera de Sacramento s/n, Almería 04120, Spain.
This work aims to investigate the occurrence of 31 antibiotics (ABs), 2 bacteria ( and spp.) and their counterpart antibiotic-resistant bacteria (carbapenem and cephalosporin families), and several antibiotic-resistant genes (ARGs) throughout a full distribution system of reclaimed water (RW) in a real-scale scenario. The RW was analyzed (i) before and after the tertiary treatment (sand filtration and chlorination), (ii) during the storage period in secondary ponds before its use in irrigation, and (iii) directly in the droppers installed in four plastic-based greenhouses over 9 months.
View Article and Find Full Text PDFNanomaterials (Basel)
August 2025
State Key Laboratory of Quantum Optics Technologies and Devices, Institute of Laser Spectroscopy, Collaborative Innovation Center of Extreme Optics, Shanxi University, Taiyuan 030006, China.
Metal halide perovskites have appeared as a promising semiconductor for high-efficiency and low-cost photovoltaic technologies. However, their performance and long-term stability are dramatically constrained by defects at the surface and grain boundaries of polycrystalline perovskite films formed during the processing. Herein, we propose a defect-targeted passivation strategy using 2-chlorocinnamic acid (2-Cl) to simultaneously enhance the efficiency and stability of perovskite solar cells (PSCs).
View Article and Find Full Text PDFMacromol Biosci
August 2025
Department of Biomaterials Sciences, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan.
Poly[(R)-3-hydroxybutyrare-co-(R)-3-hydroxypivalate] (P(3HB-co-3HPi)) films, a type of polyhydroxyalkanoate (PHA), are oxidized using photoactivated chlorine dioxide radical (ClO•) gas to generate carboxyl groups and loaded with divalent metal cations, including Cu, Zn, and Ca ions, via ionic interactions. The P(3HB-co-3HPi) films loaded with Cu ions exhibit enhanced antibacterial activity against Gram-positive bacteria (Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli) compared with untreated P(3HB-co-3HPi) films. In seawater, the biodegradation of these Cu and Zn-loaded films is initially inhibited by the antimicrobial activity of the cations and occurs gradually; therefore, loading antimicrobial divalent metal cations onto the surface of PHAs inhibits biodegradation in seawater temporarily but allows biodegradation to occur with time.
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