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Few studies have been carried out on the discrimination of precious<italic>Tetrastigma hemsleyanum</italic>, also known as Sanyeqing in China.
The title Schiff base compound, C(16)H(14)N(2)O(2), has been synthesized by the reaction of 5-amino-3,4-dimethyl-isoxazole and 2-hydr-oxy-1-naphthaldehyde. The dihedral angle between the isoxazole ring and the napthyl ring system is 3.29 (7)°. The mol-ecule adopts an E configuration about the central C=N double bond. Intra-molecular O-H⋯N hydrogen bonding generates an S(6) ring motif. In the crystal structure, π-π inter-actions are observed involving the isoxazole ring and the substituted benzene ring of the naphthyl unit, with centroid-centroid distances of 3.5200 (10) Å.
Graphitic C3 N4 (g-C3 N4 ) is used as a low-cost organic oxygen evolution reaction (OER) electrocatalyst. The integration of ultrathin g-C3 N4 nanosheets with graphene leads to g-C3 N4 /graphene composites with high OER activity and good durability. X-ray photoelectron spectroscopy (XPS) studies suggest that the OER activity results from pyridinic-N-related active sites. This catalyst provides an alternative to OER catalysts based on transition metals.
Additional file 1. Cartesian co-ordinates of optimized geometries and cif files of 3a and 3b are given in supporting information. Experimental 1H,13C-NMR are also pasted in supporting information along with HOMOâ LUMO surfaces, simulated UVâ vis. Spectra and Tables containing bond length and bond angles data.
Copper oxide decorated multi-walled carbon nanotube nanocomposites (CuO·MWCNT NCs) were prepared using a simple wet-chemical technique in basic medium.
Polypyrrole (PPy) and Polypyrrole/MoS<sub>2</sub> (PPy/MoS<sub>2</sub>) nanocomposites were successfully prepared, characterized and studied for ammonia sensing properties. The as-prepared PPy and PPy/MoS<sub>2</sub> nanocomposites were confirmed by FTIR (Fourier transform infrared spectroscopy), XRD (X-ray diffraction), SEM (scanning electron microscopy) and TEM (transmission electron microscopy) techniques. The ammonia sensing properties of PPy and PPy/MoS<sub>2</sub> nanocomposites were studied in terms of change in DC electrical conductivity on exposure to ammonia vapors followed by ambient air at room temperature. It was observed that the incorporation of MoS<sub>2</sub> in PPy showed high sensitivity, significant stability and excellent reversibility. The enhanced sensing properties of PPy/MoS<sub>2</sub> nanocomposites could be attributed to comparatively high surface area, appropriate sensing channels and efficiently available active sites. The sensing mechanism is explained on the basis of simple acid-base chemistry of polypyrrole.
Coating properties of new Ni‐La‐ferrites/epoxy resin nanocomposites has been achieved using modified epoxy resin with Ni‐La‐ferrite nanoparticles in the form of NiLaFeO 4 /epoxy nanocomposites using electrochemical impedance and sorption of water measurements. Simple solution method with ultrasonic assistance was used in the preparation of the new nanocomposites in situ while epoxy resin was prepared. The new materials were characterized by X‐ray diffraction analysis, thermogravimetric analysis, scanning electron microscopy, and electrochemical impedance spectroscopy. The nanocrystalline NiLaFeO 4 showed a good distribution and high compatibility forming strong interfacial adhesion within the epoxy matrix. Furthermore, it had ability to facilitate thermal degradation of the epoxy resin nanocomposite due to its catalytic effect. Temperatures at 10, 25, 50% weight loss and the normalized solid residue left at 500°C (NR500) were measured. The presence of nanocrystalline NiLaFeO 4 stabilized the char residue obtained at 500°C in the resulting composites. The Ni‐La‐ferrite nanoparticles decreased water sorption (WS) of the epoxy. The 5% and 10%‐ Ni‐La‐ferrites/epoxy nanocomposites showed least amount of WS among the epoxy composites. The 5 and 10% Ni‐La‐ferrite nanoparticles contents enhanced significantly the barrier behavior of the epoxy as coating of stainless steel. POLYM. COMPOS., 36:1875–1883, 2015. © 2014 Society of Plastics Engineers
MgTi<sub>2</sub>O<sub>5</sub> (magnesium dititanate) nanoparticles were prepared by a simple hydrothermal assisted post-annealing method and characterized with various analytical techniques. The catalytic properties (sonocatalytic, photocatalytic and sonophotocatalytic activity) were evaluated using the degradation of triphenylmethane dyes (crystal violet, basic fuchsin, and acid fuchsin). The sonophotocatalytic activity of MgTi<sub>2</sub>O<sub>5</sub> nanoparticles towards crystal violet was found to be ~2.9 times higher than the photocatalytic activity and ~20 times higher than that of the sonocatalytic processes. In addition, the sonophotocatalytic efficiency of MgTi<sub>2</sub>O<sub>5</sub> nanoparticles was found to be remarkable for the degradation of basic fuchsin (cationic dye) and acid fuchsin (anionic dye). The mechanism of these catalytic activities has been discussed in detail.
Graphene, a single layer 2-dimensional structure nanomaterial with unique physicochemical properties (e.g. high surface area, excellent electrical conductivity, strong mechanical strength, unparalleled thermal conductivity, remarkable biocompatibility and ease of functionalization), has received increasing attention in physical, chemical and biomedical fields. This article selectively reviews current advances of graphene based materials for biomedical applications. In particular, graphene based biosensors for small biomolecules (glucose, dopamine etc.), proteins and DNA detection have been summarized; graphene based bioimaging, drug delivery, and photothermal therapy applications have been described in detail. Future perspectives and possible challenges in this rapidly developing area are also discussed.
Abstract Novel steroidal (6 R )‐spiro‐1,3,4‐thiadiazoline derivatives have been synthesized by the cyclization of steroidal thiosemicarbazones. Thiosemicarbazones have been synthesized by the reaction of steroidal ketones with thiosemicarbazide. All the compounds have been characterized by IR, 1 H NMR, mass and elemental analyses. The antibacterial activities of these compounds have been first tested in vitro by the disk diffusion assay against two Gram‐positive and two Gram‐negative bacteria, and then the minimum inhibitory concentration (MIC) values have been determined with the reference of standard drug amoxicillin. The results showed that steroidal thiadiazoline derivatives exhibited better antibacterial activity than the steroidal thiosemicarbazone derivatives. Chloro and acetoxy substituents on the 3 β ‐position of the steroidal thiadiazoline ring increased the anti‐bacterial activity. Among all the compounds, compounds 7 and 8 were found better inhibitors as compared to the respective drug amoxicillin.
