This work describes the preparation and characterization of biogenic modified silica from rice hull ash and its use as a sorbent of cadmium ions. Thus, an agro-industrial residue has been used to produce a new adsorbent product which is able to remove toxic elements. Mesoporous biogenic silica was obtained by alkaline extraction of sodium silicate by hydrolysis with the sol-gel process, and it was modified with salen using 1,2-dichloroethane as a spacer. The surface area of the silica was measured by nitrogen adsorption/desorption analysis. Surface modification was measured by Fourier transform infrared spectroscopy. The degree of functionalization was obtained by elemental analysis. This work showed that biogenic modified silica can be produced in aqueous media from rice hull ash using a simple method, providing an alternative method for adsorbent preparation. Thermogravimetric analysis showed that the salen-modified silica is stable up to 209 degrees C. The modified silica displays appropriate structural characteristics for an adsorbent. The cylindrical pores, open at both ends, allow free diffusion of cadmium ions to the adsorption sites on the silica surface. The surface modification increases cadmium adsorption on the silica surface 100-fold. The salen-modified silica showed specific adsorption for Cd(2+) of 44.52 mg/g SiO2 at cadmium concentration of 100 mg/l.
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http://dx.doi.org/10.1080/09593330902854160 | DOI Listing |
Chin Med
January 2025
State Key Laboratory of Natural Medicines, School of Traditional Chinese Pharmacy, China Pharmaceutical University, No. 639 Longmian Road, Nanjing, 211198, China.
Background: Cell membrane chromatography (CMC) is a biochromatography with a dual function of recognition and separation, offering a distinct advantage in screening bioactive compounds from Chinese medicines (CMs). Yindan Xinnaotong soft capsule (YD), a CM formulation, has been widely utilized in the treatment of cardiovascular disease. However, a comprehensive mapping of the myocardial protective active compounds remains elusive.
View Article and Find Full Text PDFInt J Biol Macromol
January 2025
College of Chemistry and Chemical Engineering, Southwest Petroleum University, Chengdu 610500, PR China; Engineering Research Center of Oilfield Chemistry, Ministry of Education, Chengdu 610500, PR China; Oil & Gas Field Applied Chemistry Key Laboratory of Sichuan Province, Chengdu 610500, PR China. Electronic address:
In this study, polyamide/silica/sodium alginate (SA) composite (PA-Si-SA) was successfully prepared in one-step benzoxazine-isocyanide chemistry (BIC)/sol-gel process at room temperature. The chemical structure and fundamental properties of PA-Si-SA were characterized by FT-IR, solid-state C NMR, XPS, XRD, SEM, BET and TG, etc. The presence of anionic SA and diverse N, O-containing functional segments (amide, tertiary amine, alkyl/phenol -OH, Si-O-Si, and COO) in PA-Si-SA endows it synergistic complexation capability toward Pb and Cd.
View Article and Find Full Text PDFBMC Oral Health
January 2025
Department of Endodontics, Faculty of Dentistry, Ordu University, Ordu, 52200, Turkey.
Background: Immature maxillary central teeth can be managed by using several treatment options. The aim of this finite element stress analysis study was to evaluate the effect of different treatment procedures on the stresses on immature maxillary incisor teeth models that generated on cone beam computed tomography, by trauma and bite forces.
Methods: A total of 11 different models consisting of revascularization treatment using MTA and biodentine and the state of the root apex formed with cement after treatment, apexification, modified apexification, traditional root canal treatment and two different control groups have been created.
BMC Oral Health
January 2025
Department of Basic Medical Science, Faculty of Medicine, Yozgat Bozok University, Yozgat, 66100, Türkiye, Turkey.
Background: Although surface finishing processes are effective against Streptococcus mutans biofilm, the mechanism of action of saliva with different acidity values has not been studied in detail. This study aims to produce four different all-ceramic materials in a single session with CAD/CAM devices and apply two different surface finishing processes, glazing and polishing, and then determine the retention of Streptococcus mutants on the surfaces of the materials in saliva with varying levels of acidity.
Methods: Zirconia-reinforced lithium silicate (Vita Suprinity, Vita Zahnfabrik, Bad Saöckingen, Germany), monochromatic feldspar (Vitablocs Mark 2, Vita Zahnfabrik, Bad Saöckingen, Germany), leucite glass ceramic (IPS Empress CAD, Ivoclar Vivadent, Liechtenstein), and monolithic zirconia (Incoris TZI (Cerec) Sirona, Germany) were used in the study.
Am J Epidemiol
December 2024
Univ Rennes, CHU Rennes, Inserm, EHESP, Irset (Institut de recherche en santé, environnement et travail) - UMR_S 1085, F-35000 Rennes, France.
Attributable burden of disease estimates reported population-wide do not reflect social disparities in exposures and outcomes. This makes one of the influential scientific tools in public health decision-making insensitive to the distribution of health impacts between socioeconomic groups. Our aim was to use the often-overlooked distributive property of the population attributable fraction (PAF) to quantitatively partition the population burden attributed to know risk factors into subgroups defined by their socioeconomic position (SEP).
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