Zerovalent iron (ZVI) is an environmental-friendly reactive reagent for recovering heavy metals. However, the detailed recovery mechanism remains unclear due to a lack of quantitative analysis of recovery products. Herein, microscale ZVI, nanoscale ZVI and Ni/Fe nanoparticles were used to recover Pb(II) in aqueous solution and a sequential extraction procedure (SEP) was applied to determine the formed lead species quantitatively. At high initial Pb(II) concentration (500 mg L), more than 99.5% of Pb(II) was immobilized by Ni/Fe and n-ZVI, whereas m-ZVI caused inferior recovery efficiency (<25%). XRD and XPS results revealed that Pb(II) was reduced to Pb prior to the formation of metal hydroxides as the external shell of ZVI. SEP results showed that the fraction bound to carbonates (PbO), fraction bound to iron oxides and exchangeable fraction were the main lead species conducted by Ni/Fe, n-ZVI and m-ZVI, respectively. Consequently, (co-)precipitation and specific adsorption dominated Pb(II) recovery by Ni/Fe and n-ZVI, whereas m-ZVI conducted Pb(II) recovery mainly via weak adsorption. The reactivity of ZVI toward Pb(II) followed the increasing order of m-ZVI << n-ZVI ≤ Ni/Fe. The detailed mechanisms of Pb(II) recovery conducted by different ZVI were proposed.
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http://dx.doi.org/10.1016/j.jhazmat.2018.03.005 | DOI Listing |
JMIR Res Protoc
January 2025
UK Health Security Agency, London, United Kingdom.
Background: Due to advances in treatment, HIV is now a chronic condition with near-normal life expectancy. However, people with HIV continue to have a higher burden of mental and physical health conditions and are impacted by wider socioeconomic issues. Positive Voices is a nationally representative series of surveys of people with HIV in the United Kingdom.
View Article and Find Full Text PDFEnviron Geochem Health
January 2025
Ecosphere Resilience Research Centre, Faculty of Applied Sciences, University of Sri Jayewardenepura, Nugegoda, 10250, Sri Lanka.
Studies regarding geochemical partitioning and leaching behavior of Hofmeister ions, which is considered as a risk/causative factor for chronic kidney disease of unknown etiology (CKDu), are scarce. Therefore, Hofmeister ions' leaching behavior of partially weathered rocks from CKDu endemic (Girandurukotte) and non-endemic (Sewanagala) areas, Sri Lanka were compared. Rock mineralogy was analyzed using X-ray Diffraction, and total ion contents were determined using alkaline and acid digestions.
View Article and Find Full Text PDFCardiovasc Diagn Ther
December 2024
Editorial Office, AME Publishing Company, Hong Kong, China.
Background: The adherence to the Animals in Research: Reporting In Vivo Experiments (ARRIVE) guidelines across the journals that initially published the guidelines and if adherence has improved since the guidelines update, remains unknown. We aimed to quantify the level of adherence and analyze factors that might influence reporting quality among these journals.
Methods: This cross-sectional study retrospectively analyzed interventional animal experiments published in journals that released ARRIVE 1.
Anal Chim Acta
January 2025
Department of Chemistry, National Chung Hsing University, Taichung City, 402202, Taiwan, ROC. Electronic address:
Background: To integrate valves, manifolds, and solid-phase extraction (SPE) columns into a compact device is technically difficult. Four-dimensional printing (4DP) technologies, employing stimuli-responsive materials in three-dimensional printing (3DP), are revolutionizing the fabrication, functionality, and applicability of stimuli-responsive analytical devices that can show time-dependent shape programming to enable more complex geometric designs and functions. However, 4D-printed stimuli-responsive actuators and valves utilized to control flowing streams in SPE applications remain rare.
View Article and Find Full Text PDFJ Intensive Care Med
January 2025
Division of Critical Care Medicine, Department of Pediatrics, Ann & Robert H. Lurie Children's Hospital of Chicago, Chicago, IL, USA.
Objective: To determine the prognostic value of the Pediatric Sequential Organ Failure Assessment (pSOFA) to discriminate critical events, including code events and intubations, in the pediatric intensive care unit (PICU).
Methods: We performed an observational cohort study of all critical events in a quaternary care PICU between 5/2020 and 4/2023. Critical events were extracted from our hospital communications platform and from the electronic health record (EHR).
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