Signature of room temperature ferromagnetism in Mn doped CeO2 nanoparticles

We report structural and magnetic properties of Mn doped CeO₂ nanoparticles using X-ray diffraction (XRD), field emission transmission electron microscopy (FE-TEM) and dc magnetization measurements. XRD results infer that all the samples have single phase nature and lattice parameters decrease with Mn doping. The particle size calculated using XRD and TEM analysis was found to decrease with Mn doping. Field cooled magnetization measurement shows that the transition temperature is above room temperature. Magnetic hysteresis loop studies indicate that undoped and Mn doped CeO₂ nanoparticles show weak ferromagnetic behavior at room temperature.     

Magnetic, optical and structural property studies of Mn-doped ZnO nanosheets

We report the synthesis of pure and Mn doped ZnO in the form of nanosheets using a simple and single step procedure involving a microwave assisted chemical method. As prepared Mn-doped ZnO nanosheets were characterized using X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), ultra violet-visible (UV-Vis), Raman spectroscopy and magnetization measurements. The structural studies using XRD and TEM revealed the absence of Mn-related secondary phases and showed that Mn-doped ZnO comprise a single phase nature with wurtzite structure. FESEM and TEM micrographs show that the average diameter of Mn-ZnO assembled nanosheets is about approximately 50 nm, and the length of a Mn-doped ZnO nanosheet building block which is made up of thin mutilayered sheets is around approximately 300 nm. Concerning the Raman scattering spectra, the shift in peak position of E2 (high) mode toward low frequencies due to the Mn doping could be explained well by means of the spatial correlation model. Magnetic measurements showed that Mn-doped ZnO nanosheets exhibit ferromagnetic ordering at or above room temperature.     

Influence of nitrogen gas flow rate on the structural, morphological and electrical properties of sputtered TiN films

In this work, nanocrystalline titanium nitride (TiN) films have been deposited by reactive DC magnetron sputtering technique on the Si/SiO₂ (100) substrates. The influence of nitrogen gas flow rate [0, 3, 5, 7 and 9 sccm (standard cubic centimeter per minute)] on the structural, morphological and electrical properties of the nanocrystalline TiN films has been studied. As-deposited TiN films have been characterized by using X-ray diffraction (XRD), XPS (X-ray photoelectron spectroscopy), FESEM (field emission scanning electron microscopy) and four point probe resistivity measurement, respectively. The XRD patterns revealed the HCP symmetry for pure Ti (N₂ = 0 sccm) with (002) preferred orientations, and the FCC symmetry for TiN (N₂ = 3, 5, 7 and 9 sccm) films having (111) preferred orientations. The lattice parameters were found to be a = 2.950 ?, c = 4.681? for the Ti (N₂ = 0 sccm) film and a = 4.250Å for the TiN films. The presence of different phases such as TiN and TiO₂ were confirmed by XPS analysis. The FESEM images showed a smooth morphology of the film with columnar grain structures. The grain size of the TiN films was found to decrease from 22 to 15 nm as the nitrogen flow rate is increased from 0 to 9 sccm. The electrical resistivity measurement showed that the resistivity of the film increased from 11 × 10^?6 to 17 × 10^?6 Ohm cm on increasing nitrogen flow rate from 3 to 9 sccm, having the lowest resistivity of 11 × 10^?6 Ohm cm for the film deposited at 3 sccm nitrogen flow.     

A new standard security policy language

The rapid increase and complication of threats on organizations' assets makes developing organizational security policies a pressing need. Organizations should develop policies that regulate and control the access of their assets. Security policies define the guidelines that can be used to determine the security measures to be employed in an organization to keep assets secured. Security officers used to write policies in their natural language, resulting in less readable, less maintainable, and ambiguous policy statements. Consequently, the possibility of developing automation systems for policy management was very low. With the increase of business, organizations developed several security policies to control different assets, systems, and data. These policies are often scattered over different environments and different models. That makes them difficult to be tracked for implementation and updates.     

A UNIFIED THREE POINT APPROXIMATING SUBDIVISION SCHEME

In this paper, we propose a three point approximating subdivision scheme, with three shape parameters, that unifies three different existing three point approximating schemes. Some sufficient conditions for subdivision curve C<'0> to C<'3> continuity and conver- gence of the scheme for generating tensor product surfaces for certain ranges of parameters by using Laurent polynomial method are discussed.The systems of curve and surface de- sign based on our scheme have been developed successfully in garment CAD especially for clothes modelling.     

Synthesis of novel hollow microflowers (NHMF) of Nb3O7F,their optical and hydrogen storage properties

A two step, facile surfactant free hydrothermal route was adopted to synthesize Nb₃O₇F novel hollow microflowers (NHMF). Time dependent experiments were performed which suggested Nb₃O₇F-NHMF were formed due to Ostwald-ripening process. Raman spectroscopy was conducted to understand different vibrational modes of Nb₃O₇F-NHMF. Its characteristic band at 692 cm⁻¹ was observed which is associated to NbO₆ octahedron sharing. The bandgap of 3.2 eV was calculated by using UV-VIS-NIR absorption spectrum. Considering importance of layered structures in energy storage applications, hydrogen storage ability of Nb₃O₇F-NHMF were measured for the first time. The maximum values of hydrogen absorption for Nb₃O₇F-NHMF at 373 K and 473 K were 0.789 wt.% and 1.08 wt.%, respectively. The hydrogen storage measurements revealed the potential of Nb₃O₇F-NHMF as prospective material for energy storage applications.     

Characterization and antibacterial property of Kapok fibers treated with chitosan/AgCl–TiO2 colloid

The aim of this research is to investigate the antibacterial activity of Kapok fibers modified with AgCl/TiO₂ and Chitosan colloid. A very simple, single-step (pad-dry-cure) method was used for the application of AgCl/TiO₂ and Chitosan colloid on kapok fibers, the chemicals used are easily available. Different blend ratios of chitosan and AgCl/TiO₂ colloid were applied to the bleached kapok fibers and antibacterial properties were assayed against gram positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria. The treated kapok fibers were characterized by Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). It was observed that the bacterial growth was significantly reduced in the samples which had a higher concentration of chitosan and AgCl/TiO₂ colloid. However, a significant reduction in bacterial growth with the use of this colloid was observed.     

Transmission lines differential protection based on the energy conservation law

This paper proposes a differential protection scheme for transmission lines using the energy conservation law. The real power signals at both ends (sending and receiving) of the line are compared with a pre-specified value, if the resultant is more than this value, an internal fault is indicated in the transmission line zone.The proposed technique is evaluated using PSCAD/EMTDC program configurated to model the effect of faults on typical 500 kV transmission line. Extensive simulation studies show that this protection scheme has the ability to discriminate internal faults fast and accurately, and is more reliable than conventional biased differential protection scheme, and suitable for all types of lines. Details of the proposed relay design are given in the paper; also results of some performance studies are given.     

An organizational maturity model of software product line engineering

Software product line engineering is an inter-disciplinary concept. It spans the dimensions of business, architecture, process, and the organization. Some of the potential benefits of this approach include cost reduction, improvements in product quality and a decrease in product development time. The increasing popularity of software product line engineering in the software industry necessitates a process maturity evaluation methodology. Accordingly, this paper presents an organizational maturity model of software product line engineering for evaluating the maturity of organizational dimension. The model assumes that organizational theories, behavior, and management play a critical role in the institutionalization of software product line engineering within an organization. Assessment questionnaires and a rating methodology comprise the framework of this model. The objective and design of the questionnaires are to collect information about the software product line engineering process from the dual perspectives of organizational behavior and management. Furthermore, we conducted two case studies and reported the assessment results using the organizational maturity model presented in this paper.     

A new MOSFET output conductance measurement technique

A new technique is presented for accurate measurement of the output conductance of a metal-oxide semiconductor field effect transistor (MOSFET). This technique allows the measurement of output conductance down to the sub μS region with an accuracy of better than 1%. Measurements in this range of output conductance are plagued by stray capacitances and noise. The new technique effectively combats these sources of error. The above-mentioned accuracy is maintained even when the susceptance due to the stray capacitance is as much as five times the conductance being measured