Fabrication and magnetic properties of cobalt nanorod arrays containing a number of ultrafine nanowires electrodeposited within an AAO/SBA-15 template

Arrays of cobalt nanorods consisting of a number of nanowires have been fabricated by the electrochemical method using an anodic-aluminum oxide (AAO)/mesoporous-silica (SBA-15) composite. Microscopic studies clearly display that each nanorod (with a diameter of ∼200 nm) of the array was consisting of a number of cobalt nanowires which exhibit an average diameter of 3 nm. The observed hysteresis loops measured at room temperature indicate that the magnetic shape anisotropy of cobalt mesostructures, i.e. the parallel and perpendicular squarenesses of 0.5 and 0.1, respectively have been estimated. The maximum value of the coercivity measured perpendicular to the sample axis shows a value of 330 Oe and it was found that the coercivity decreases by increasing the temperature which is possibly caused by thermal disturbance inside the arrays.     

Synthesis and characterization of porous crystalline SiC thin films prepared by radio frequency reactive magnetron sputtering technique

Hexagonal SiC thin films have been deposited using radio frequency reactive magnetron sputtering technique by varying the substrate temperature and other deposition conditions. Prior to deposition surface modification of the substrate Si(1 0 0) played an important role in deposition of the hexagonal SiC structure. The effect of substrate temperature during deposition on structure, composition and surface morphology of the SiC films has been analyzed using atomic force microscopy, Fourier transform infrared spectroscopy and spectroscopic ellipsometry. X-ray diffraction in conventional θ-2θ mode and omega scan mode revealed that the deposited films were crystalline having 8H-SiC structure and crystallinity improved with increase of deposition temperature. The bonding order and Si-C composition within the films showed improvement with the increase of deposition temperature. The surface of thin films grew in the shape of globes and columns depending upon deposition temperature. The optical properties also showed improvement with increase of deposition temperature and the results obtained by ellipsometry reinforced the results of other techniques.     

A discontinuous Galerkin method to solve chromatographic models

This article proposes a discontinuous Galerkin method for solving model equations describing isothermal non-reactive and reactive chromatography. The models contain a system of convection-diffusion-reaction partial differential equations with dominated convective terms. The suggested method has capability to capture sharp discontinuities and narrow peaks of the elution profiles. The accuracy of the method can be improved by introducing additional nodes in the same solution element and, hence, avoids the expansion of mesh stencils normally encountered in the high order finite volume schemes. Thus, the method can be uniformly applied up to boundary cells without loosing accuracy. The method is robust and well suited for large-scale time-dependent simulations of chromatographic processes where accuracy is highly demanding. Several test problems of isothermal non-reactive and reactive chromatographic processes are presented. The results of the current method are validated against flux-limiting finite volume schemes. The numerical results verify the efficiency and accuracy of the investigated method. The proposed scheme gives more resolved solutions than the high resolution finite volume schemes.     

Impact of double-diffusivity convection in nanofluids and induced magnetic field on peristaltic pumping of a Carreau fluid in a tapered channel with different waveforms

Journal of Thermal Analysis and Calorimetry - In the present article, importance of double-diffusivity convection in nanofluids on peristaltic pumping of Carreau fluid in tapered channel with...     

Catalytic nonthermal plasma using efficient cobalt oxide catalyst for complete mineralization of toluene

Research on Chemical Intermediates - The remarkable rise in industrial utilization of volatile organic compounds has increased their presence in environmental matrices, which is a menace for human...     

Characterization of Volatile Components of Chassalia chartacea and Its Acetylcholinesterase Inhibitory Activity

Chemistry of Natural Compounds -     

Structural and electronic properties of the adsorption molecules on Co and Fe/N-doped graphene towards the application in direct liquid fuel cell

Structural Chemistry - Co and Fe-nitrogen-doped graphene model (MN4) with an N/C ratio of 0.043 is tested for oxygen reduction reaction. The models and calculations were done using density...     

Molecular and Structural Analysis of Specific Mutations from Saudi Isolates of SARS-CoV-2 RNA-Dependent RNA Polymerase and their Implications on Protein Structure and Drug–Protein Binding

The COVID-19 pandemic caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has stressed the global health system to a significant level, which has not only resulted in high morbidity and mortality but also poses a threat for future pandemics. This situation warrants efforts to develop novel therapeutics to manage SARS-CoV-2 in specific and other emerging viruses in general. This study focuses on SARS-CoV2 RNA-dependent RNA polymerase (RdRp) mutations collected from Saudi Arabia and their impact on protein structure and function. The Saudi SARS-CoV-2 RdRp sequences were compared with the reference Wuhan, China RdRp using a variety of computational and biophysics-based approaches. The results revealed that three mutations—A97V, P323I and Y606C—may affect protein stability, and hence the relationship of protein structure to function. The apo wild RdRp is more dynamically stable with compact secondary structure elements compared to the mutants. Further, the wild type showed stable conformational dynamics and interaction network to remdesivir. The net binding energy of wild-type RdRp with remdesivir is -50.76 kcal/mol, which is more stable than the mutants. The findings of the current study might deliver useful information regarding therapeutic development against the mutant RdRp, which may further furnish our understanding of SARS-CoV-2 biology.     

Exploring 2-Tetradecanoylimino-3-aryl-4-methyl-1,3-thiazolines Derivatives as Alkaline Phosphatase Inhibitors: Biochemical Evaluation and Computational Analysis

The current study focused on the laboratory approach in conjunction with computational methods for the synthesis and bioactivity assessment of unique 2-tetradecanoylimino-3-aryl-4-methyl-1,3-thiazolines (2a–2k). Processes included cyclizing 1-aroyl-3-arylthioureas with propan-2-one in the presence of trimethylamine and bromine. By using spectroscopic techniques and elemental analyses, structures were elucidated. To assess the electronic properties, density functional theory (DFT) calculations were made, while binding interactions of synthesized derivatives were studied by the molecular docking tool. Promising results were found during the evaluation of bioactivity of synthesized compounds against alkaline phosphatase. The drug likeliness score, an indicator used for any chemical entity posing as a drug, was within acceptable limits. The data suggested that most of the derivatives were potent inhibitors of alkaline phosphatase, which in turn may act as lead molecules to synthesize derivatives having desired pharmacological profiles for the treatment of specific diseases associated with abnormal levels of ALPs.     

Mild and Efficient Solvent‐Free Friedel–Crafts Acylation of Reserpine

The first mild, efficient, solvent‐free Friedel–Crafts acylation of reserpine has been developed, which resulted in the synthesis of 10‐ and 12‐acylated homologues in high overall yields.