International Journal of Nano Dimension
Volume:3 Issue: 2, Autumn 2012

This study is concerned with the synthesizing of Cu-Zn nanoferrite particles in the laboratory applying simple techniques. The morphology of the synthesized nano-particles was analyzed using Transmission Electron Microscopy (TEM), and the minerals were identified using X-ray diffraction (XRD). The nano material was used to replace 1- 4 percent by weight of Portland cement in cement pastes and mortars. The microstructure and compressive strength of the composites were then evaluated. The microstructure was characterized by means of Scanning Electron Microscope (SEM) analysis and the compressive strength was evaluated at 7 and 28 days. While some specimens were tested at normal temperature, other specimens were tested after 2-hour exposure at elevated temperatures of 200oC and 400oC. The results showed that it was possible to synthesize nano-particles having an average size of 12 nanometers. Also, the test results revealed that the optimum content of the nano-ferrite was 1% to produce the maximum increase in the compressive strength. Adding the optimum dose of nanoparticles helped to produce a denser microstructure. The paste and mortar specimens showed general tendency to lose strength after exposure to the elevated temperatures.

CMC polymer is used as an additive to decrease water loss and mud-cake-thickness in mud drilling. In this study, the effect of CMC and CMC nanoparticles on water loss and mud-cake-thickness in mud drilling is investigated. CMC nanoparticles are made by using of ball milling and their size is measured by Particle size analyzer. CMC and CMC nanoparticles which were prepared by Hamilton batch mixer and with certain percent suggested by API, were added to the water-based mud drilling. The amount of water loss and mud cake thickness was measured by filter press. It was found that adding CMC nanoparticles in comparison with conventional CMC resulted in desirable reduction of amount of water loss and mud cake thickness.

The objective of the present study was to prepare controlled release formulation of Moxifloxacin hydrochloride ocular nanoparticles. The nanoparticles were prepared by solvent displacement method using Eudragit RL 100 as a polymer. Different formulations were prepared by varying the ratios of drug and polymer and varying the ratios of organic and aqueous phase. The formulations were evaluated in terms of particle size, FTIR, drug entrapment efficiency and in vitro drug release profile was examined. The anti bacterial activity against gram positive and gram negative bacteria were determined. In vivo studies were carried out by Draize test. The mean particle size for drug loaded formulations was found to be below 200 nm. The zeta potential remained in the range of positive values for all batches +10 mV to +40mV. The formulation possesses good antibiotic activity against Escherichia coli, Bacillus subtilus and Staphylococcus aureus microorganism and no eye irritation on in-vivo testing.

A nanocomposite membrane Cu2+ ion-selective electrode has been constructed using a new compound ethyl 1,2,3,4-tetrahydro-4-(4- methoxyphenyl)-6-methyl-2-oxopyrimidine-5-carboxylat (ETMOC) as a neutral ionophore. The electrode works properly. It responds to Cu2+ ion with a sensitivity of 29.5 ± 0.2 mV/decade over the range 1.0 × 10−9 to 5.0 × 10−1M at pH 3.0-8.0. The limit of detection was 4.5 × 10−10 M. It has a response time of < 6s and can be used for at least 3 months without any divergence in potentials. The proposed electrode shows fairly good discrimination of Cu2+ ion from several cations. Then, electrolyte solution system, CuCl2, KCl, H2O in the concentration range from dilute to near saturate from the thermodynamic viewpoint was investigated. The thermodynamic investigations were performed based on Pitzer ioninteraction model by processing experimental data of potentiometric. The thermodynamic investigations were successfully performed by the evaluation of potentiometric experimental data.

The paper is focused on the formation of hydroxyapatite nanoparticles (HAp) in polyelectrolyte-modified microemulsions, in a microemulsion template phase consisting of cyclohexane, water, cationic surfactant and cosurfactant, in the presence of Na-polyacrylate (PAA) as an anionic polyelectrolyte. It is shown that PAA, can be incorporated into the individual inverse microemulsion droplets. The microemulsion droplets and PAA-filled microemulsion droplets can be successfully used as a template phase for the nanoparticles formation. Prepared HAp in presence of polyelectrolyte has a different morphology from samples which are synthesized in absence of polyelectrolyte. PAA leads to formation of needle-like HAp (20-30nm in diameter and 100-200nm in length). Formation of HAp at room temperature was confirmed by X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR). Size and morphology of the HAp samples were characterized using transmission electron microscopy (TEM).

We report on the synthesis, morphology, chemically and structurally of TiO2-CuO-SiO2 nanostructure with different precursors molar ratio and calcined temperatures. In the present work, ternary reactive powders in the TiO2-CuO-SiO2 systems have been obtained using the sol-gel method, by the simultaneous gelation of all cations. The compounds and other elements change in special chemical and physical qualities in this nano oxide. Powders and coatings have been characterized by XRD, SEM, EDX and FTIR. X-ray diffraction showed the formation of nano crystalline CuO (Tenorite) and anatase phases. The average crystallite size was calculated by using X-ray diffraction analysis. The activation energy (E) of nanoparticles formation during thermal treatment were calculated. The lattice strain evaluated by Williamson-Hall's equation. SEM revealed that nanoaggregation structure formed by increasing the calcined temperature and grains like to make a spherical shape. EDX spectroscopy confirmed the composition of the ternary powders and coating, which are formed during the gelation process. FTIR spectra showed that Si-O-Ti, Ti-O, Cu-O, Ti-O-Ti, Ti-OH and Si-O-Si bonds are formed and indicated that titanium is in four-fold coordination with oxygen in the SiO4-. The effects of chemical compositions and the strong process on the surface topography and the crystallization of anatase and CuO (Tenorite) were studied. With increasing the molar ratio (content of CuO) in as-prepared state, the formation of rod region was more prominent than agglomerate region.

The aim of this study is to evaluate the influence of pH on the synthesis of nanocrystallines cobalt ferrite by combination of sol- gel auto combustion and ultrasonic irradiation methods. Two different fuels, urea and thiourea, along with metal nitrates (oxidant) were used to prepare CoFe2O4 powders. The morphology of the resulting powders was investigated. The powders were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Phase pure spinel cobalt ferrite powder was obtained at pH values 6 and 7 after the calcinations at 750˚C when urea was used as the fuel; however, the samples obtained using thiourea fuel contained impurities. The average crystalline size was 21 and 37 nm, respectively, for the samples containing urea and thiourea.

In this research, the effect of the first order magnetic field on the ground-state of a centered hydrogenic donor impurity in a GaAs/AlAs spherical quantum dot has been calculated. The perturbation method has been used within the framework of effective mass approximation for these calculations. Overall, the analysis shows that a proper choice of quantum dot radius and magnetic field can significantly change the normalized binding energy. The concluded information may be used to calculate the small changes in quantum dot radius and thus detect different magnetic field strengths.

The increased surface area-to-volume ratio of nanoparticles, quantum size effects and the ability to tune surface properties through molecular modification make nanostructures ideal for environmental remediation. The present piece of work reports the preparation and characterization of nano cellulosic fibers (NCFs) with further polymeric reinforcement using vinyl sulphonic acid for the remediation of cationic toxic metals from water bodies. The modified NCFs exhibited enhancement in sorption efficiency (more than 90 %) and stability in terms of increased (3 to 5) regeneration cycles for Cd (II), Pb (II), Ni (II) and Cr (III) ions in single and multi metal solutions. Novel NCFs were also characterized on the basis of FTIR and TGA techniques and found to have enough potential for environmental remediation.

In the present work, we report a suitable approach for the preparation of BaTiO3 nanostructures via the hydrothermal condition using Dolapix ET85 as surfactant. The powders were investigated by Xray diffraction (XRD), scanning election microscopy (SEM), energydispersive X-ray spectroscopy (EDAX), field emission transmission electron microscopy (FETEM), selected area electron diffraction (SAED), high resolution transmission electron microscopy (HRTEM) and zetasizer measurement. As a matter of fact, the hydrothermal method guarantees the production of BaTiO3 nanoparticles with desired morphology for commercial applications. In addition, uniform particles, size distribution and purity of samples are highly dependent on the applied hydrothermal condition.

One of the bio-sensing mechanisms is mechanical. Rather than measuring shift in resonance frequency, we adopt to measure the change in spring constant due to adsorption, as one of the fundamental sensing mechanism. This study explains determination of spring constant of a surface functionalized micro machined micro cantilever, which resonates in a trapezoidal cavity-on Silicon <100> wafer, with the resonating frequency of 7000 cycles per second. This thin-flimsy-oxide microcantilever has a typical shape, and the tip of the micro-cantilever is dipcoated with chemically and biologically active material. The change in mass, due to adsorption, is detected by measuring the change in spring constant. The Force-Distance spectroscopy is used to detect the change in spring constant. The experimental results, show that the mechanical sensing scheme used, permit this surface functionalized micro machined micro cantilever to be used as a molecular mass sensor. The mechanical spring behaviour of a micro-cantilever, a micro-mechanical device can be used to develop ultra-tech micro-mechanical system using computer interface.