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The catalytic activity of a monolithic catalyst with nanosized Pt and Au particles on ZnO/Al2O3 (Pt-Au/ZnO/Al2O3/M) prepared by a wash-coat method was examined, specifically for toluene oxidation. Scanning electron microscopy image showed clearly the formation of a ZnO/Al2O3 layer on the monolith. Nanosized Pt-Au particles on ZnO/Al2O3/M with different sizes could be found in the Pt-Au/ZnO/Al2O3/M catalyst. The conversion of toluene decreased with increasing toluene concentration and was also largely affected by the feed flow rate. The Pt-Au/ZnO/Al2O3/M catalysts prepared in this work have almost the same activity (molecules of toluene per second) compared with a powder Pt-Au/ZnO/Al2O3 catalyst with the same loadings of Pt and Au components; thus this catalyst could be used in controlling air pollution with very low concentrations and high flow rate.Urea was used to disperse nanoscale zero-valent iron (NZVI) for reduction of Cr(VI) to Cr(III) in aqueous solution. Scanning electron microscope and fourier transform-infrared spectra investigations demonstrated that urea could effectively increase the dispersion of NZVI resulting in more effective reduction sites (ERS) for Cr(VI) ions. Batch reduction experiments indicated that the reductive capacity of urea dispersed NZVI (UNZVI) was significantly improved, as the reductive efficiency reached 96.8% under optimal condition compared with the raw NZVI (72.14%). Additionally, the NZVI was stable for at least 28 days after urea treatment. The dispersion mechanism was proposed that the steric hindrance effect of the urea coating on the surface might play a key role in dispersing the NZVI particles.Glancing angle deposition (GLAD) was employed to fabricate the SiOx-In2-xO3-y axial heterostructure nanocolumn. The fabricated heterostructure nanocolumn was annealed at 550 °C for 1 hour at open air condition. The XRD analysis revealed the polycrystalline nature of the annealed SiOx-In2-xO3-y nanocolumn. The emission at 378 nm (~3.3 eV, FWHM 39.101 nm) from Photoluminescence (PL), corresponds to main band gap of In2O3. The In2-xO3-y-SiOx nanocolumn based Schottky detector processed maximum photoresponsivity of 199 A/W at 375 nm, as well as UV-Vis broad band detection. The high internal gain of ~659 at UV region (375 nm) was calculated for the device. The detector exhibited increase in photoresponsivity with decrease in room temperature upto 160 K, which further reduced at low temperature. A very sharp rise time (~1.82 s) and decay time (~1.78 s) was recorded at the applied potential of -2 V and -3 V.Fabrication of novel nanostructures based on carbon nanotubes has been a focus of recent interest since they are expected to inherit excellent properties of carbon nanotube. To find new nanotube-based nanostructures, it is important to find a new growth mode or process. This paper reports the formation of a multiwalled carbon nanotube that has bi-layered structure and is partly flattened. Transmission electron microscopy observations suggest that the outer multiwalled layer was formed first from a Fe catalyst nanoparticle, and was partly flattened during the growth. Then the catalyst nanoparticle worked again to form the inner multiwalled tube moving inside the outer tube and became flattened at the same position of the outer tube. It is likely that the inner growth gave an expansion stress against the flattened outer tube; nevertheless, the flattened part of the outer tube remained. This observation evidences that the flattening of the nanotube occurred simultaneously during the growth and was stabilized by structural defect.Superfine silver nanowires (Ag NWs) with diameter of 40~50 nm and length of 5~10 µm have been synthesized by the self-seeding polyol reduction process using silver nitrate as the silver source, polyvinyl pyrrolidone (PVP) as the structural directing agent, ethylene glycol (EG) as the reducing agent and AgBr as the mediator. The influence of different factors on the growth of Ag NWs was studied. The morphology and crystalline phase of Ag NWs were characterized by the field emission scanning electron microscopy (SEM) and X-ray diffraction (XRD) respectively. The results indicate that the introduction of potassium bromide (KBr) is helpful for growth of Ag NWs with a high aspect ratio, as AgBr colloids formed in the initial stage and the dissociation reaction of AgBr colloids would largely influence the delivering rate of Ag+ ions, which controls the nucleation and growth of the Ag NWs. Finally, the possible growth mechanism of Ag NWs was discussed.Gd2O3 encapsulated NiFe2O4 core-shell nano-particles (CSNPs) have been synthesized by chemical route. The phase formation of the materials is confirmed by X-ray diffraction analysis. The average particle size is found to be 60 nm by transmission electron microscope. The band gap of NiFe2O4/Gd2O3 CSNPs is obtained by UV-visible absorption spectroscopy. The observed band gap of 4.38 eV lies in between the individual band gap of Gd2O3 and NiFe2O4. The frequency-dependent dielectric relaxation of the material is investigated in the temperature range from 303 K to 543 K. The temperature dependent relaxation times are found to obey Arrhenius law having activation energy of 0.3 eV. The Nyquist plots of impedance data are analyzed by the RC equivalent circuit having a constant phase element. The dielectric relaxation is modelled by Havriliak-Negami technique in the electric modulus formalism. The frequency dependent conductivity spectra follow the double power law.The electrochemical oxidation of p-nitrophenol (p-Np) has been studied on glassy carbon electrode modified with the single-walled carbon nanotubes/silver nanowires hybrids (SWNTs-Ag) by using cyclic and differential pulse voltammetry. p-Np is irreversibly oxidized at +0.88 V (vs. the Ag/AgCl) in PBS solutions of pH 7.4. The modified electrodes display the detection sensitivity of 0.0212 µA/µM with an unusually wide linear response of 5-1700 µM (R2 = 0.998) and the detection limit of 1 µM. The current response of SWNTs-Ag modified electrode to p-Np is better than that of SWNTs or Ag nanowires modified electrode under the same concentration. Combining the adsorption ability of SWNTs and the conductivity of SWNTs and Ag nanowires, the detection performance of SWNTs-Ag modified electrode to p-Np was greatly improved.The compositional dependence of the structure and properties of spinel-type solid solutions, Zn(A,Ga)2O4 was investigated by comparison with samples hydrothermally prepared and those after heat treatment at 1000 °C in air. https://www.selleckchem.com/products/tetrazolium-red.html Nanocrystalline spinel-type solid solutions in the whole composition range in the ZnAl2O4-ZnGa2O4 system were directly formed from the aqueous precursor solutions of ZnSO4, Al(NO3)3 and Ga(NO3)3 under hydrothermal conditions at 180 °C for 5 h in the presence of tetramethylammonium hydroxide. The incorporation of aluminum into the lattice, Zn(AlxGa1-x)2O4, resulted in lower crystallinity of the spinel. The relationship between the lattice parameter of as-prepared samples and the Al atomic ratio in the spinel composition was slightly apart from the ideal linear relationship that was obtained in the samples after heat treatment at 1000 °C. The optical band gap of both as-prepared solid solutions and those heat treated linearly increased from 4.1~4.2 to 5.25 eV by the incorporation of aluminum ion into the lattice, Zn(AlxGa1-x)2O4. Two main broad-band emission spectra centered at around 360 and 430 nm in the range of 300-600 nm were observed in the spinel solid solutions under excitation at 270 nm, thought their broad-band emission spectra and their peak wavelengths subtly changed depending on the composition and heat treatment.A simple and facile method was developed to synthesize well-dispersed cuprous oxide nanospheres with uniform morphology and the size in the range of 400-600 nm. Cuprous oxide nanospheres were obtained through the chemical reduction of copper acetate by fructose in the presence of ethylene glycol and de-ionized water. X-ray powder diffraction (XRD), Energy dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), UV-Vis spectroscopy (UV-Vis) and transmission electron microscopy (TEM) as well as high-resolution transmission electron microscopy (HRTEM) were used to characterize the obtained nanoparticles. The influence of time, temperature and the solvent on the formation of cuprous oxide was investigated. The growth process of cuprous oxide was analyzed and the mechanism of crystal growth was proposed. The photocatalytic activity of degradation of methyl orange (MO) under visible light irradiation was also investigated. It was found that the product of cuprous oxide had efficient catalytic for degradation MO.Nanotechnology has found wide use in biomedical applications and the food and bioprocessing industry. In this light, we demonstrate a facile strategy to prepare bifunctional monodisperse silica nanospheres encapsulating chitosan-coated magnetic nanoparticles and CdTe quantum dots. The size of these composite spheres can be adjusted from 90 nm to 500 nm by varying the concentration of ammonia, water, tetraethyl orthosilicate, and the ratio of the chitosan-coated magnetic nanoparticles and CdTe quantum dots. The composite spheres are characterized using scanning electron microscope analyses, transmission electron microscope analyses, energy-dispersed spectrum studies, Malvern Zetasizer, vibrating sample magnetometer, and fluorescence microscopy. The spheres exhibit good monodispersion and favorable superparamagnetic and fluorescent properties. The luminescence of the spheres can be varied by using different types of coated quantum dots. Such composite spheres with tunable characteristics allow for external manipulation of research systems by magnetic fields together with the real-time fluorescent monitoring of multiple samples. The abovementioned properties can potentially be exploited for application in the biomedical and biosensing fields.Carbon-coated nano-sized LiMnPO4/C particles are synthesized by polyol method using low-cost glucose as the carbon source. The X-ray diffraction patterns of the synthesized samples are well indexed to the orthorhombic olivine-LiMnPO4 structure. The morphology studies using FE-SEM and HR-TEM images clearly illustrate thin layered carbon coatings on LiMnPO4 particles of sizes ranging between 50~100 nm. The LiMnPO4/C particles delivers an initial discharge capacity of 151 mA h g-1 at a current density of 1.6 mA g-1 in the voltage range of 2.5-4.3 V with impressive capacity retentions.In this study we performed O2/Ar plasma treatment to remove the polycaprolactone on hydroxyapatite nanopowder and polycaprolactone (HAp-NP/PCL) composite film. After plasma ashing, the HAp-NP was exposed on the composite film. The 25 wt% HAp-NP/PCL treated with plasma showed the hydrophilic surface property with reducing the aging effect. The MTT and ALP results indicated that the plasma etching increased the biocompatibility of HAp-NP/PCL composite film. The present simple plasma etching technique can be applicable in a development of biomaterials.Highly uniform Bi2Te3 nanotubes with various morphologies are synthesized via a solution process using Te nanowires as a sacrificial template. The morphology of Bi2Te3 nanotubes can be controlled by varying the solvent system. The reaction between Bi and Te in triethylene glycol (TEG) produces Bi2Te3 nanotubes with plate-like surface morphology, whereas rough surface morphology of the Bi2Te3 nanotubes is obtained by the reaction in ethylene glycol (EG). The crystal structures and morphologies of nanotubes are investigated X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM). The effect of solvent on the evolution of morphology of the Bi2Te3 nanotubes is investigated. The effect of surface morphology on the thermoelectric properties is discussed.