Hemoglobin detection on AgO surface enhanced Raman scattering (SERS)-substrates

Human hemoglobin (2.2×10 M) detection has been demonstrated on AgO surface enhanced Raman scattering (SERS)-substrates. Hot spots that enable detection of hemoglobin using SERS are formed at the silver nanoclusters induced by the photo-activation of AgO under Raman excitation wavelength (633 nm). Higher enhancement is observed at integration time (20 s) and threshold energy density (12 M J/cm). At higher excitation energy densities photo-chemical (or photo-thermal) activity of the hemoglobin molecules are dominated. These results are critical to the future use of AgO films as SERS substrates for the detection of biological molecules

DETECTING OUTLIERS USING EUCLIDEAN DISTANCE IN UNSUPERVISED METHOD

The interest in outlier is difficult because they include important and practical data in a number of domain names, for example invasion and recognition of fraud in addition to medical diagnosis. It had been in recent occasions observed that distribution of point reverse-neighbour counts become skewed in high dimensions that results within phenomenon acknowledged as hubness. We offer a unifying vision of role concerning reverse nearest neighbour counts within problems relevant to without supervision outlier detection, and concentrate on high dimensionality effects on without supervision outlier-detection techniques additionally to hubness phenomenon. The appearance of anti-hubs is caused by high dimensionality when neighbourhood dimensions are small when in comparison to data size. These anti-hubs occurrence is strongly consort with outlier in high-dimensional in addition to low dimensional data

Morphology and Curie temperature engineering in crystalline La0.7Sr0.3MnO3 films on Si by pulsed laser deposition

Of all the colossal magnetoresistant manganites, La0.7Sr0.3MnO3 (LSMO) exhibits magnetic and electronic state transitions above room temperature, and therefore holds immense technological potential in spintronic devices and hybrid heterojunctions. As the first step towards this goal, it needs to be integrated with silicon via a well-defined process that provides morphology and phase control, along with reproducibility. This work demonstrates the development of pulsed laser deposition (PLD) process parameter regimes for dense and columnar morphology LSMO films directly on Si. These regimes are postulated on the foundations of a pressure-distance scaling law and their limits are defined post experimental validation. The laser spot size is seen to play an important role in tandem with the pressure-distance scaling law to provide morphology control during LSMO deposition on lattice-mismatched Si substrate. Additionally, phase stability of the deposited films in these regimes is evaluated through magnetometry measurements and the Curie temperatures obtained are 349 K (for dense morphology) and 355 K (for columnar morphology)-the highest reported for LSMO films on Si so far. X-ray diffraction studies on phase evolution with variation in laser energy density and substrate temperature reveals the emergence of texture. Quantitative limits for all the key PLD process parameters are demonstrated in order enable morphological and structural engineering of LSMO films deposited directly on Si. These results are expected to boost the realization of top-down and bottom-up LSMO device architectures on the Si platform for a variety of applications. (C) 2014 AIP Publishing LLC

Silver oxide (AgO) thin films for Surface Enhanced Raman Scattering (SERS) studies

Present paper reports the use of photo-activated silver oxide thin films for the study of Surface Enhanced Raman Scattering (SERS). The silver oxide thin films grown by pulsed laser deposition (PLD) are excited with 488 nm wavelength of power density 47watts/cm 2 (for 5 minutes) to produce nano silver clusters. Rhodamine 6G (10 -7M) is employed for detecting the enhanced Raman signal

Microstructural and ionic transport studies of hydrothermally synthesized lanthanum fluoride nanoparticles

This article presents the structural and transport characteristics of hydrothermally synthesized LaF3 nanoparticles with an average crystallite size of 35nm. The phase formation of the material is confirmed by both X-ray diffraction and transmission electron microscopy techniques. In addition, phase purity of the LaF3 nanoparticles is corroborated by micro-Raman spectroscopy studies. The complex impedance plots at different temperatures reveal that the conductivity is predominantly due to the intrinsic bulk grains and the conductivity relaxation is non-Debye in nature. The frequency variation of conductivity exhibits dispersion at higher frequencies that can be explained with the frame work of Almond-West formalism. The conduction process is controlled by the mobility of the charge carriers and the charge of transport of mobile fluoride ions occur through hopping mechanism. The scaling behavior of both frequency dependence of conductivity and complex impedance plots at different temperatures confirm that the relaxation mechanism of the mobile fluoride ions is independent of temperature

Physical properties of high performance fluoride ion conductor BaSnF4 thin films by pulsed laser deposition

This article presents the results on the growth and characterization of BaSnF4 thin films on glass substrates prepared by pulsed laser deposition technique. The structural results of BaSnF4 thin film carried out by glancing angle X-ray diffraction technique indicates the formation of the film with similar structure (tetragonal, P-4/nmm) to the bulk target material. The absorption coefficient and band gap of the film is determined by suitable analysis of the transmittance spectra. The transport properties of the thin films are studied using impedance spectroscopy in the temperature range of 323-573 K. The frequency-dependent imaginary part of impedance plot shows that the conductivity relaxation is non-Debye in nature. The scaling behavior of the imaginary part of impedance at various frequencies indicates temperature-independent relaxation behavior

Hybrid copper doped titania/polythiophene nanorods as efficient visible light-driven photocatalyst for degradation of organic pollutants

The hybrid Cu–TiO2/polythiophene nanorods (HNRs) were prepared by modified sol–gel technique at low temperature through oxidative polymerization of thiophene. The prepared HNRs and Cu–TiO2 nanorods without polymer (CTNRs) were characterized by using XRD, TEM, IR, UV–vis DRS and XPS. IR, XPS and XRD confirm polythiophene (PTh) covered Cu–TiO2 nanorod in hybrid with rutile phase without affecting the crystal form of TiO2. TEM analysis reveals the shape and morphology of CTNRs and HNRs. TEM images of HNRs show that the metal oxide has nanorods like shape with lengths and diameters of about 35–60 and 15–25 nm respectively. From UV–visible DRS spectra, HNRs exhibit a broad and strong absorption in visible range, indicating that the incorporation of PTh onto the surface of Cu–TiO2 nanorod in hybrid can extend the photo response range of TiO2. The photocatalytic activity of HNRs shows higher degradation when compared with CTNRs under visible light irradiation by degradation of Rhodamine B (RhB) and Orange G (OG). There is no degradation of PTh was observed under visible light irradiation till five runs which is examined from photocatalytic activity, which indicates stability and reusability of photocatalyst