The use of dispersión-free solvent extraction, through microporous hydrophobic membrane has been investigated. The hollow fiber contactor, with surface area of 1.4 m2 was used to extract Cr(VI) (0.005-0.12 g/L from aqueous sulphuric acidic media (pH 2.5-4.2 +/- 0.05). Several parameters such as extractant concentration, feed acidity and metal concentration in the initial aqueous solution were investigated. Results revealed that 15% v/v Cyanex 923 in Exxsol D-100 as organic phase and feed in the 2.5 pH range, gave optimum extraction (exceeding 95%) of Cr(VI) and it was possible to strip using 10 g/L hydrazine sulfate (also with recoveries exceeding 95%). In this step, Cr(VI) is immediately reduced to the less hazardous Cr(III) state. Results also showed that under the various experimental conditions, chromium(VI) extraction was rate-controlled by the interfacial reaction on the membrane surface. Typical overall mass transfer coefficients values are 4.2 x 10(-5) and 3.6 x 10(-6) cm/s for extraction and stripping operations, respectively.
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Sci Rep
January 2025
School of Earth and Environmental Sciences, Cardiff University, Main Building, Park Place, Cardiff, CF10 3AT, UK.
Dienia is a small, pantropical genus of epidendroid Malaxideae orchids. The floral lip is upwardly directed and does not serve as a landing platform for pollinators. This role has been assumed by sepals and/or gynostemium or whole inflorescence.
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January 2025
Dental Health Department, College of Applied Medical Sciences, King Saud University, P.O. Box 10219, Riyadh, 11433, Saudi Arabia.
In this study, the endophytic fungus Coniothyrium chaingmaiense-KUMBMDBT-25 was isolated from the healthy stem of Euphorbia tirucalli, mass cultivated by submerged fermentation, and extracted using ethyl acetate as a solvent. The extract was subjected to GC-MS analysis. The synthesized Con-AgNPs were characterized through various bioanalytical methods.
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December 2024
Department of Chemistry, Government College University, Lahore, Pakistan. Electronic address:
The current research focused on extraction optimization of bioactive compounds from Strychnos potatorum seeds (SPs) using an eco-friendly glycerol-sodium acetate based deep eutectic solvent (DES). The optimization was accomplished using response surface methodology (RSM) and artificial neural networking (ANN). The independent variables included shaking time (A), temperature (B), and solvent-to-feed ratio (C), and the responses were the extraction yield, total phenolic content (TPC), total flavonoid content (TFC), antioxidant activity (DPPH), and antidiabetic activity (α-amylase inhibitory activity).
View Article and Find Full Text PDFInorg Chem
January 2025
Department of Chemistry, Western Michigan University, Kalamazoo, Michigan 49008, United States.
The supramolecular binding exclusively by H-bonds of SeO, MoO and WO ions to form nanojars of the formula [EO⊂{-Cu(μ-OH)(μ-pz)}] (; E = Se, Mo, W; = 28-34; pz = pyrazolate) was studied in solution by electrospray ionization mass spectrometry, variable temperature, paramagnetic H NMR and UV-vis spectroscopy, and in the solid state by single-crystal X-ray crystallography. These large anions allow for the observation of a record nanojar size, (E = Mo, W). Six crystal structures are described of nanojars of varying sizes with either SeO, MoO or WO entrapped ions, including the first example of a cocrystal of two different nanojars in crystallographically unique positions, and .
View Article and Find Full Text PDFAlzheimers Dement
December 2024
University of Louisville, Lousiville, KY, USA.
Background: Chronic, excessive alcohol consumption causes neurodegeneration and is associated with an increased risk for Alzheimer's disease (AD) and other dementias. Moreover, there has been a consistent rise in alcohol consumption in older adults in the past few decades. However, there is minimal research showing how alcohol consumption affects AD neuropathogenesis and biological mechanisms remain unclear.
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