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Iranifam M.,Islamic Azad University at Maragheh
TrAC - Trends in Analytical Chemistry | Year: 2014

The current state of the art in chemiluminescence (CL) detection methods provides clinicians and researchers interested in oncology with efficient tools for early detection and accurate diagnosis of cancer. In this context, CL methods are powerful with the capability of detecting cancerous cells and cancer biomarkers, among other applications. Moreover, these methods can aid in increasing the survival chances of cancer patients undergoing chemotherapy and radiotherapy by sensitive monitoring of their progress when undergoing treatment. This article reviews the literature on the applications of CL methods in cancer detection and therapy (e.g., determination of circulating tumor cells, cancer biomarkers and anticancer drugs, and photodynamic therapy as a light-delivery system and dosimetry tool). © 2014 Elsevier B.V. Source

Esrafili M.D.,Islamic Azad University at Maragheh
Journal of Molecular Modeling | Year: 2012

A theoretical study was performed to examine hydrogen and halogen bonds properties in gas phase and crystalline dichloroacetic acid (DCAA). The specific pattern of O-H...O, C-H...O, HCl, Cl...O and Cl...Cl interactions in DCAA dimers is described within the quantum theory of atoms in molecules (QTAIM) formalism. Based on QTAIM results, a partial covalent character is attributed to the O-H...O hydrogen bonds in DCAA, whereas all the C-H...O, Cl···O and Cl...Cl intermolecular interactions are weak and basically electrostatic in nature. MP2/6-311++G** calculations indicate that the interaction energies for DCAA dimers lie in the range between -0.40 and -14.58 kcal mol-1. One of the most important results of this study is that, according to energy decomposition analyses, halogen bonds are largely dependent on both electrostatic and dispersion interactions. For those nuclei participating in the hydrogen-bonding and halogen-bonding interactions, nuclear quadrupole coupling constants exhibit significant changes on going from the isolated molecule model to the crystalline DCAA. Of course, the magnitude of these changes at each nucleus depends directly on its amount of contribution to the interactions. © Springer-Verlag 2012. Source

We report geometries, stabilization energies, symmetry adapted perturbation theory (SAPT) and quantum theory of atoms in molecules (QTAIM) analyses of a series of carbene-BX 3 complexes, where X=H, OH, NH 2, CH 3, CN, NC, F, Cl, and Br. The stabilization energies were calculated at HF, B3LYP, MP2, MP4 and CCSD(T)/aug-ccpVDZ levels of theory using optimized geometries of all the complexes obtained from B3LYP/aug-cc-pVTZ. Quantitatively, all the complexes indicate the presence of B-C carbene interaction due to the short B-C carbene distances. Inspection of stabilization energies reveals that the interaction energies increase in the order NH 2 > OH > CH 3 > F > H > Cl > Br > NC > CN, which is the opposite trend shown in the binding distances. Considering the SAPT results, it is found that electrostatic effects account for about 50% of the overall attraction of the studied complexes. By comparison, the induction components of these interactions represent about 40% of the total attractive forces. Despite falling in a region of charge depletion with δ 2 ρBCP >0, the B-C carbene bond critical points (BCPs) are characterized by a reasonably large value of the electron density ( ρBCP) and H BCP <0, indicating that the potential energy overcomes the kinetic energy density at BCP and the B-C carbene bond is a polar covalent bond. © Springer-Verlag 2011. Source

Amini M.,Islamic Azad University at Maragheh | Haghdoost M.M.,Sharif University of Technology | Bagherzadeh M.,Sharif University of Technology
Coordination Chemistry Reviews | Year: 2013

This review mainly discusses the application of oxido-peroxido Molybdenum(VI) complexes as catalysts or mediators in homogeneous or heterogeneous catalytic systems for oxidations of olefins, sulfides, alcohols, alkanes, and amines toward the synthesis of a variety of organic compounds, such as epoxides, sulfoxides, aldehydes and ketones, carboxylic acids, alcohols and nitroso compounds. © 2012 Elsevier B.V. Source

We demonstrate a method which directly grows large areas of graphene on carbon paper and glassy carbon (GC) substrates from graphite powder and anionic surfactant, sodium dodecyl sulfate, assisted electrochemical exfoliation. The electrochemically reduced graphene has been carefully characterized by scanning electron microscopy (SEM) and electrochemical techniques. Particularly, SEM images show enhanced growth of graphene structures formed of 'urchin' objects. The CV spectra illustrate that a variety of the oxygen-containing functional groups has been thoroughly removed from the graphite plane via electrochemical reduction. Potential peak (Ep) of graphene electrode in [Fe(CN) 6] 3-/4- solution is as small as 212 mV which is 168 mV smaller than that of graphite electrode. This could be attributed to the high quality graphene accelerating the electron transfer rate in [Fe(CN) 6] 3-/4- electrochemistry. Finally, platinum was electro reduced onto the GC and graphene modified GC based electrodes for use in methanol oxidation. The catalytic activities of graphene-supported Pt nanoparticles and Pt-GC electrocatalysts for methanol oxidation were 1900 and 915.5 A g -1 Pt, which can reveal the particular properties of the exfoliated graphene supports. © 2012 Published by Elsevier Ltd. Source

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