Mechanosynthesis of MFe 2

Adsorption of Pb(II) from aqueous solution using MFe2O4 nanoferrites (M = Co, Ni, and Zn) was studied. Nanoferrite samples were prepared via the mechanochemical method and were characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), micro-Raman, and vibrating sample magnetometry (VSM). XRD analysis confirms the formation of pure single phases of cubic ferrites with average crystallite sizes of 23.8, 19.4, and 19.2 nm for CoFe2O4, NiFe2O4, and ZnFe2O4, respectively. Only NiFe2O4 and ZnFe2O4 samples show superparamagnetic behavior at room temperature, whereas CoFe2O4 is ferromagnetic. Kinetics and isotherm adsorption studies for adsorption of Pb(II) were carried out. A pseudo-second-order kinetic describes the sorption behavior. The experimental data of the isotherms were well fitted to the Langmuir isotherm model. The maximum adsorption capacity of Pb(II) on the nanoferrites was found to be 20.58, 17.76, and 9.34 mg·g−1 for M = Co, Ni, and Zn, respectively

Is the donor-acceptor electronegativity a good indicator for the surface enhanced Raman scattering (SERS)?

In this work, we study the interaction of neutral and ionic forms of Ag 8 and Au 8 with glycine to investigate the role of these interactions in the chemical enhancement (CE) component of the surface enhanced Raman scattering (SERS) effect. It is widely accepted that the charge transfer between metallic nanostructures and molecular species is a key issue in the underlying CE mechanism; consequently under this framework, and supported by the density functional theory, we introduce two recently described parameters, donor (π -) and acceptor (π +) electronegativity as useful concepts for the prediction of the charge transfer process and the concomitant CE effect. From this work, it could be inferred that the minimum binding energy (BE) necessary for the CE to take place averages 30 kcal/mol. For the systems we present here, CE is more intense when BE is more negative and this occurs when there is a substantial charge transfer. Thus, as π - and π + represent good parameters for analyzing the charge transfer process, they are also good indicators of the contribution of CE to the SERS effect. © 2012 Wiley Periodicals, Inc

The 3?UTR 1188 A/C polymorphism in the interleukin-12p40 gene (IL-12B) is associated with lepromatous leprosy in the west of Mexico

Serum blood samples of euthyroid and thyroidectomized rats treated with thyrotropin-releasing hormone (TRH) were analyzed on aluminum substrates using the near-infrared Raman spectroscopy (830 nm). Spectra of thyroid-stimulating hormone (TSH), TRH and prolactin standards were obtained. Differences between Raman spectra profiles of control and Tx + TRH samples groups were found. These differences were confirmed by the linear discriminant analysis (LDA), which presents a good classification between groups. It is supposed that these differences are produced by the increment of TSH in the thyroidectomized rats. " 2004 Elsevier B.V. All rights reserved.",,,,,,"10.1016/j.saa.2004.03.016",,,"http://hdl.handle.net/20.500.12104/45032","http://www.scopus.com/inward/record.url?eid=2-s2.0-9544237139&partnerID=40&md5=1c57c3f016e93cdca87e42d8aaabf358",,,,,,"01-feb",,"Spectrochimica Acta - Part A: Molecular and Biomolecular Spectroscopy",,"8

Mechanosynthesis of MFe2O4 (M = Co, Ni, and Zn) Magnetic Nanoparticles for Pb Removal from Aqueous Solution

Adsorption of Pb(II) from aqueous solution using MFe2O4 nanoferrites (M = Co, Ni, and Zn) was studied. Nanoferrite samples were prepared via the mechanochemical method and were characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), micro-Raman, and vibrating sample magnetometry (VSM). XRD analysis confirms the formation of pure single phases of cubic ferrites with average crystallite sizes of 23.8, 19.4, and 19.2 nm for CoFe2O4, NiFe2O4, and ZnFe2O4, respectively. Only NiFe2O4 and ZnFe2O4 samples show superparamagnetic behavior at room temperature, whereas CoFe2O4 is ferromagnetic. Kinetics and isotherm adsorption studies for adsorption of Pb(II) were carried out. A pseudo-second-order kinetic describes the sorption behavior. The experimental data of the isotherms were well fitted to the Langmuir isotherm model. The maximum adsorption capacity of Pb(II) on the nanoferrites was found to be 20.58, 17.76, and 9.34 mg·g−1 for M = Co, Ni, and Zn, respectively