In this study, the performance of phosphoric acid activated montmorillonite (PAmmt) was evaluated by cesium ions adsorption experiments. The PAmmt samples were obtained by activating with 1, 3 and 5 mol L(-1) of phosphoric acid, respectively under reflux for 3, 12, and 24h. Experimental results demonstrated that the treatment of raw K-10 montmorillonite with phosphoric acid increased the materials' affinity for Cs uptake and no significant amount of suspension solids were produced. A relatively insignificant variation in the CEC value was observed. Furthermore, PAmmt also showed high adsorption selectivity toward Cs ions. The improved sorptive properties were mainly related to the increased surface area and the relatively higher surface charge density. Increased specific surface area was the resulted from partial decomposition of lamellar structure of mmt; while the higher surface charge density was caused by the protonation of octahedral Al-OH sites during the acid activation. Generally speaking, stronger acid concentration and longer activation times would produce relatively more decomposed PAmmt particles. However, as the activation exceeds 3h, the precipitation of Si(4+) would passivate PAmmt against further acid attacks. Based upon our results, acid activation by phosphoric acid could produce PAmmt samples with high sorption capacity and selectivity, and good structural integrity, which are beneficial to be used at radioactive waste repository.
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http://dx.doi.org/10.1016/j.jhazmat.2009.08.091 | DOI Listing |
Sci Rep
January 2025
Advanced Glass and Glass Ceramic Research Laboratory, Department of Physics, University of Lucknow, Lucknow, 226007, India.
Recently, 3-D porous architecture of the composites play a key role in cell proliferation, bone regeneration, and anticancer activities. The osteoinductive and osteoconductive properties of β-TCP allow for the complete repair of numerous bone defects. Herein, β-TCP was synthesized by wet chemical precipitation route, and their 3-D porous composites with HBO and Cu nanoparticles were prepared by the solid-state reaction method with improved mechanical and biological performances.
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January 2025
Department of Chemistry, School of Advanced Sciences, Vellore Institute of Technology, Vellore, Tamil Nadu, 632014, India.
Hydroxyapatite (HA) is an important constituent of natural bone. The properties of HA can be enhanced with the help of various ionic substitutions in the crystal lattice of HA. Iron (Fe) is a vital element present in bones and teeth.
View Article and Find Full Text PDFJ Appl Biomater Funct Mater
January 2025
Department of Neurosurgery, Neurocenter of South Switzerland, Ente Ospedaliero Cantonale, Lugano, Switzerland.
Introduction: Intensive research is dedicated to the development of novel biomaterials and medical devices to be used as grafts in reconstructive surgery, with the purpose of enhancing their therapeutic effectiveness, safety, and durability. A variety of biomaterials, from autologous bone to polymethylmetacrylate, polyether ether ketone, titanium, and calcium-based ceramics are used in cranioplasty. Porous hydroxyapatite (PHA) is reported as a possible material for bone reconstruction, with good signs of biocompatibility, osteoconductive and osteointegrative properties.
View Article and Find Full Text PDFFront Biosci (Landmark Ed)
January 2025
Department of Oral and Maxillofacial Surgery, The First Affiliated Hospital of Fujian Medical University, Fujian Provincial Key Laboratory of Stomatology, National Regional Medical Center, Binhai Campus of The First Affiliated Hospital, 350005 Fuzhou, Fujian, China.
Background: In this study, we prepared a porous gradient scaffold with hydroxyapatite microtubules (HAMT) and chitosan (CHS) and investigated osteogenesis induced by these scaffolds.
Methods: The arrangement of wax balls in the mold can control the size and distribution of the pores of the scaffold, and form an interconnected gradient pore structure. The scaffolds were systematically evaluated and for biocompatibility, biological activity, and regulatory mechanisms.
Pharmaceuticals (Basel)
January 2025
Forschungszentrum Jülich GmbH, Institute of Neuroscience and Medicine, Nuclear Chemistry (INM-5), Wilhelm-Johnen-Str., 52428 Jülich, Germany.
The radiotracer [F]JK-PSMA-7, a prostate cancer imaging agent for positron emission tomography (PET), was previously synthesized by indirect radiofluorination using an F-labeled active ester as a prosthetic group, which had to be isolated and purified before it could be linked to the pharmacologically active Lys-urea-Glu motif. Although this procedure could be automated on two-reactor modules like the GE TRACERLab FX2N (FXN) to afford the tracer in modest radiochemical yields (RCY) of 18-25%, it is unsuitable for cassette-based systems with a single reactor. To simplify implementation on an automated synthesis module, the radiosynthesis of [F]JK-PSMA-7 was devised as a one-pot, two-step reaction.
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