Publications

Abstract New electromagnetic nanocomposites were prepared from polyaniline (PANI)/oxidized single‐walled carbon nanotubes (OxSWCNTs)/NiFe 2 O 4 by in situ polymerization of aniline using hexanoic acid as a soft template. OxSWCNT and NiFe 2 O 4 were prepared first so as to be used in the formulation of PANI composites. Transmission electron microscope (TEM) results revealed the formation of PANI nanoparticles of 60 nm diameter, OxSWCNT of 24 nm, and NiFe 2 O 4 of 54 nm. Also, TEM image of the ternary composite indicated agglomerative coating of PANI appearing as a gray shells and black core of NiFe 2 O 4 with widening the diameter of OxSWCNT to be around 66 nm. Dc conductivity was measured as a function of temperature. Magnetic susceptibility was measured as a function of temperature and magnetic field intensity. All samples revealed NiFe 2 O 4 ‐dependent ferromagnetism. The activation energies for dc conductivity suggest that the conductivity is owing to hopping conduction mechanism. A synergistic effect between NiFe 2 O 4 and PANI/OxSWCNT is observed. POLYM. COMPOS.,, 2012. © 2012 Society of Plastics Engineers

This study demonstrates a significant burden of influenza-associated SARI hospitalizations in Saudi Arabia, with the highest rates observed in the elderly and young children. Seasonal variation was evident, highlighting the urgent need to enhance influenza vaccination coverage, particularly among high-risk groups such as the elderly and young children, to reduce severe outcomes. Expanding sentinel surveillance to more regions and incorporating detailed clinical and economic data are recommended to better inform public health policies. Strengthening pandemic preparedness and tailoring vaccination campaigns based on seasonality and age-specific risk will be critical for mitigating the influenza burden in Saudi Arabia.

The metal-free-mediated thermal reaction of [60]fullerene with aromatic aldehydes and inactive primary amines bearing electron-donating groups at the α-position afforded a series of 2-aryl-5-alkyl-fulleropyrrolidines, including the scarce 2-aryl-5-benzyl-fulleropyrrolidines as a mixture of cis and trans isomers. With rare exceptions, the mixture of cis and trans isomers could be easily isolated by column chromatography, with a preference of cis isomers as major products. A plausible mechanism for the formation of fulleropyrrolidines is also proposed.

The direct mix of aqueous FeCl<sub>3</sub> and o-phenylenediamine (OPD) solutions at room temperature leads to supramolecular microfibrils of OPD dimers generated by the oxidation of OPD monomers by FeCl<sub>3</sub>. In this paper, we demonstrate that the subsequent treatment of such microfibrils with a HAuCl<sub>4</sub> aqueous solution leads to Au nanoparticle (AuNP)-decorated nanoplates. The possible formation mechanism involved is also discussed. It is found that such nanocomposites can effectively catalyze both oxidization and reduction of H<sub>2</sub>O<sub>2</sub>. The sensor constructed with these nanocomposites exhibits a fast amperometric response time of less than 4 s. The linear detection range is estimated to be from 100 μM to 170 mM (r=0.997), and the detection limit is estimated to be 8 μM at a signal-to-noise ratio of 3.

The electrooxidation of cysteamine compound was carried out using convolutive cyclic voltammetry, linear sweep voltammetry and chronoamperomtry techniques at a carbon fiber microdisk electrode in 0. 1 M perchloric acid. The electrooxidation potential (E 0'' ) of cysteamine occurs at + 0.921 V. The mechanistic pathway of electrooxidation process at carbon fiber microelectrode is loss of 1 electron per molecule. The electrode process is controlled mainly by diffusion. The chemical and electrochemical parameters of the investigated system were determined experimentally and verified theoretically via digital simulation method.

Abstract A new polymeric silver(I) complex of imidazolidine-2-thione (Imt), {[Ag 2 (Imt) 3 ](NO 3 ) 2 } n ( 1 ) was prepared and its structure was determined by single-crystal X-ray diffraction analysis. The silver atoms form infinite chains with two Ag − S(Imt) − Ag strands linked to each other by sulfur atoms of μ 4 -Imt ligands. Each silver(I) ion is bound to four sulfur atoms of bridging Imt ligands in a distorted tetrahedral environment. The crystal structure is stabilized by hydrogen bonding and weak argentophilic interactions. The hydrogen bonded nitrate ions connect the 1D chains to generate a 2D layer structure.