bluuebunny/crossref_metadata_2025 huggingface dataset:
LIGHT INDUCED SOLITON SWITCHING AT THE GALLIUM-SILICA INTERFACE
Authors: NARUKA PREETI , BISSA SHIVANGI
Published: May 2013

In the present paper, we have investigated the solitonic characteristics of a pulse passing through an interface separating two nonlinear media. The first media is a thin film of gallium nanoparticles which show switching properties under optical excitation and second is a monomode optical fiber. Soliton propagation in three different phases of gallium nanoparticles have been analyzed by using the method of phase-plane analysis. Also, the critical power required for soliton propagation has been calculated.
SYNTHESIS AND HYDROGEN SENSING PROPERTIES OF CNT-ZnO NANOCOMPOSITE THIN FILMS
Authors: VYAS RISHI , SHARMA SARLA , GUPTA PARUL , SACHDEV K. , SHARMA S. K.
Published: May 2013

CNT-ZnO nanocomposite powders were synthesized by addition of carbon nanotubes (CNT) during the growth of ZnO nanoparticles using a wet-chemical method. These CNT-ZnO nanocomposites powder were then spin coated on corning glass substrates to obtain thin films which were characterized using X-ray diffraction, scanning electron microscopy and current voltage characteristics. Hydrogen sensing (50- 1000 ppm) carried out on pure and CNT-ZnO nanocomposites at operating temperature of 250 and 300°C in N2 atmosphere (0.4±0.03 mbar) revealed higher sensitivity in 2 wt.% CNT-ZnO nanocomposite thin film compared to the pure ZnO thin film.
STRUCTURAL AND DIELECTRIC STUDIES OF Pb(Zr0.65Ti0.35)O3 ELECTROCERAMIC MODIFIED BY MANGANESE
Authors: TIWARI BALGOVIND , CHOUDHARY R. N. P.
Published: May 2013

A high-temperature solid-state reaction technique was used to prepare polycrystalline samples of electrocerimic, lead zirconate titanate (PZT) modified by manganese (Mn) with Zr/Ti ratio of 65/35 (i.e., Pb(Zr0.65-xMnxTi0.35)O3 (x = 0, 0.02, 0.06, 0.10)). Preliminary structural analysis by an X-ray diffraction (XRD) technique has confirmed the formation of compounds with no pyrochlore phase. The XRD patterns clearly show that there is no major structural change of Pb(Zr0.65-xMnxTi0.35)O3 on substitution of Mn at the Zr-site. Although at higher (x=0.10) modification some small satellite peaks do appear. The micro-structural analysis of the surface of the compounds by scanning electron microscopy (SEM) suggests that the grains are uniformly and densely distributed over the entire surface of all the samples and are spherical in all the cases. Room temperature variation of εr and tanδ as a function of frequency shows that εr and tanδ decreases with rise in frequency, which is a general feature of normal ferroelectric material’s dielectric properties, irrespective of composition of the specimens. The higher value of εr at lower frequencies is due to simultaneous presence of all types of polarizations (i.e., interfacial, ionic, dipolar, electronic, space charge, etc.) in the compounds. Detailed studies of the dielectric properties reveal that the compounds showed (i) shift in Tc , and (ii) improvement in dielectric constant and loss.
PHASE TRANSITION OF PRASEODYMIUM MONO-PNICTIDES UNDER HIGH PRESSURE
Authors: GUPTA DINESH CHANDRA , RAYPURIA GAJENDRA SINGH
Published: May 2013

The Phase transition and elastic properties of Praseodymium-monopnictides have been investigated under pressure by means of a modified charge-transfer potential model which incorporates the Coulomb screening due to the delocalization of f-electron of rare-earth atom leading to many-body interactions, along with Coulomb interaction, covalency effect and overlap repulsion extended up to second-nearest neighbours. These compunds undergo transition from NaCl structure to high pressure body-centered tetragonal (BCT) structure (distorted CsCl-type P4/mmm). The calculated values of cohesive energy, lattice constant, phase transition pressure, relative volume collapse. Present model explains the Cauchy’s discrepancy correctly.
THE EFFECT OF CeO2 NANOPARTICLE DOPING ON REFINEMENT OF Y-211 PARTICLES IN POIG PROCESSED YBCO COMPOSITES
Authors: RAJU P. MISSAK SWARUP , NAIK S. PAVAN KUMAR , KUMAR N. DEVENDRA , RAJASEKHARAN T. , SESHUBAI V.
Published: May 2013

Doping of non-interacting nanoparticles in YBCO superconductors in order to get fine microstructure defects has been studied. Y-211 inclusion, itself has large potential to create structural defects without affecting Y-123 matrix phase. Nanoparticles of grain refining agent like CeO2/Pt/PtO2 are interesting dopants, especially CeO2 for being cheaper than Pt. POIG process, as is one of the advance processing techniques to get uniform distribution of fine Y-211 particles of the order of 1-2 μm, throughout the YBCO composites. Finer Y-211 particles can drastically increase the pinning centers. Introduction of fine sized CeO2 as grain refining agent to reduce the size of Y-211 particles would create additional pinning centers. In the present work, the effect of CeO2 on Y-211size and distribution in POIG processed YBCO composite was studied. It was observed that with increase in CeO2 content Y-211 particle size decreases below 1μm and even less than 0.5μm for 10 weight percent CeO2 doping. The mechanism for refinement appears to be the formation of BaCeO3 on the surface of Y-211 during liquid phase infiltration that leads to splitting of Y-211 into smaller particles.
STRUCTURAL PROPERTIES OF CHROMIUM DOPED GADOLINIUM MANGANITES
Authors: MODI ANCHIT , THAKUR RAJESH , THAKUR RASNA , GAUR N. K. , KAURAV N. , OKRAM G. S.
Published: May 2013

The Systematic investigation of structural behaviour of GdMn1-xCrxO3 (x=0, 0.1, 0.2) has been undertaken which are synthesized by conventional solid state reaction method. All the XRD reflection lines were successfully indexed according to orthorhombic perovskite structure with space group: pbnm (62). Upon chromium (Cr) doping on the Mn site the unit cell volume has reduced due to slight difference between the ionic radii of Cr 3+ and Mn 3+ compare with Pure GdMnO 3. The relation between lattice parameter infer that all the samples have O´ type orthorhombic structure which is highly distorted perovskite structure but increasing the Cr concentration the orthorhombic distortion decrease that deduce the non John Teller nature of these samples.
IMPEDANCE SPECTROSCOPY STUDIES OF NANO-CRYSTALLINE LiFePO4 CATHODE SYNTHESIZED BY HYDROTHERMAL METHOD
Authors: ROSAIAH P. , HUSSAIN O. M.
Published: May 2013

LiFePO 4 has become of great interest as storage cathodes for rechargeable lithium batteries because of their high energy density, low raw materials cost, environmental friendliness, high thermal stability. In the present investigation, lithium iron phosphate ( LiFePO 4) cathode material has been prepared by using hydrothermal synthesis. The structure of the sample has been studies by using X-ray diffraction. The XRD spectrum exhibited different characteristic peaks along with (311) predominant orientation corresponding to an orthorhombic crystal structure with Pnma space group. Electrical and dielectric properties were studied over a frequency range of 1 Hz – 1 MHz at different temperatures. The electrical conductivity was found to be increased with increasing temperature following Arrhenius relation with an estimated activation energy of 0.44 eV. The dielectric properties were analyzed in the framework of complex dielectric permittivity and complex electric modulus formalisms. The evolution of the complex permittivity as a function of frequency and temperature was investigated. Several important parameters such as activation energy, ionic hopping frequency, carrier concentration, ionic mobility and diffusion coefficient etc, were determined.
DEPENDENCY OF THERMO-PHYSICAL PROPERTIES ON SURFACE BONDING OF BN NANO-CRYSTAL
Authors: DIWAN BHOOPENDRA DHAR , KUMAR SWAMY N.
Published: May 2013

In this paper we have studied the variation of normalized per-atom pair cohesive (binding) energy and melting temperature with size and number of atom-pairs in the BN nano-crystal by simple model approach. In small nano-particles, large proportions of their atoms reside either at or near the surface, and those in clusters are basically all on the surface. So, we have to study the surface configuration in detail that leads the constancy of the crystals. Even for bulk materials, parameters that ensure this constancy involving normalized cohesive energy, surface reconstruction, iconicity, bulk structure, hybridization and charge balance, melting point. It is worthwhile to say that many of these factors are quite interdependent. These all factors influence the whole cohesive energy of crystals and give important information about the deflections from inverse size dependence. The per-atom-pair binding energy and melting temperature of BN nano-crystal is a quadratic function of the inverse of the crystal size. The binding energy and melting temperature comes near their bulk value with increasing the crystal size and same as the bulk material when the crystal size is above than 100 nm.
PREPARATION AND CHARACTERIZATION OFCe0.8Y0.2O2NANOPOWDERS USING SOL-GEL METHOD
Authors: AMARSINGH BHABU K. , DHIVYA SARANYA J. , RAJASEKARAN T. R.
Published: May 2013

Nanopowders of Ce0.8Y0.2O2were prepared by sol-gel via hydrolysis method for different hours. The prepared powders are characterized by powder X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Scanning electron microscope (SEM) and analyzed by UV-visible spectroscopy, Photoluminescence (PL) and Energy dispersive X-ray analysis (EDAX). Cubic fluorite structure of the prepared samples was confirmed by powder X-ray diffraction and the grain size of the prepared samples in the range of 12 to 33 nm. The functional groups of the prepared nanopowders are identified by FTIR spectra. The band gap energy obtained from the UV spectra. From the photoluminescence spectra, there is a mirror image relation between absorption and emission spectra. The purity of the prepared samples is confirmed by EDAX measurements.
PHOTOELECTROCHEMICAL WATER SPLITTING USING BILAYERED ZnO/SrTiO3 PHOTOELECTRODES
Authors: CHOUDHARY SURBHI , SOLANKI ANJANA , SHARMA DIPIKA , SINGH NIRUPAMA , UPADHYAY SUMANT , SHRIVASTAV ROHIT , SATSANGI VIBHA R. , DASS SAHAB
Published: May 2013

Nanostructured zinc oxide overlayered by nanoporous strontium titanate was synthesized using sol-gel method and tested in a photoelectrochemical (PEC) cell for splitting of water. It was found that compared to the pristine ZnO and SrTiO 3, the resistivity of bilayered thin film was reduced and a negative shift in open circuit potential and flatband potential of bilayered ZnO/SrTiO 3 was observed, thus improving the photocurrent density and photoconversion efficiency. Significantly, bilayered ZnO/SrTiO 3 thin film offered the best photocurrent density i.e. 0.46 mA/cm2 at 0 V/SCE. XRD, SEM and UV-Vis spectroscopic studies were carried out to explore the structural, surface morphological and optical properties of various thin films.
STRUCTURAL PROPERTIES AND MICROSTRUCTURE OF COBALT FERRITE PARTICLES SYNTHESIZED BY A SOL-GEL AUTO COMBUSTION METHOD
Authors: RAVAL ANAND , PANCHAL NITAL , JOTANIA RAJSHREE
Published: May 2013

Synthesis and characterization of Cobalt ferrite powders by a sol gel combustion process is focused in the present work. The prepared precursors was calcined at 950° C for 4 hours in order to get cobalt ferrite powder. The effect of metal nitrates/citric acid ratio (referred as x) of CoFe2O4 on structural and micro-structural properties was investigated. The structural characterization on CoFe2O4 ferrite samples were carried out using the X-ray diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FT-IR) techniques. Phase identification and crystallite size of calcined powder were determined using XRD analysis. The formation of the ferrite is confirmed by FTIR results. The morphology of prepared CoFe2O4 ferrite samples (with x = 0.5, 1.0, 1.5 and 2.0, where x is metal to citrate ratio) was studied using a scanning electron microscopy.
STRUCTURAL AND ELECTRICAL PROPERTIES OF TANTALUM PENTAOXIDE (Ta2O5) THIN FILMS – A REVIEW
Authors: RATHEE KANTA , MALIK B. P.
Published: May 2013

Down scaling of complementary metal oxide semiconductor transistors has put limitations on silicon dioxide to be used as an effective dielectric. It is necessary to replace the SiO2with a physically thicker layer of oxides of high dielectric constant. Thus high k dielectrics are used to suppress the existing challenges for CMOS scaling. Many new oxides are being evaluated as gate dielectrics such as Ta2O5, HfO2, ZrO2 , La2O3, HfO2, TiO2, Al2O3, Y2O3etc but it was soon found that these oxides in many respects have inferior electronic properties to SiO2. But the the choice alone of suitable metal oxide with high dielectric constant is not sufficient to overcome the scaling challenges. The various deposition techniques and the conditions under which the thin films are deposited plays important role in deciding the structural and electrical properties of the deposited films. This paper discusses in brief the various deposition conditions which are employed to improve the structural and electrical properties of the deposited films.
BIANCHI TYPE VI0 INFLATIONARY COSMOLOGICAL MODEL IN GENERAL RELATIVITY
Authors: BALI RAJ , POONIA LAXMI
Published: May 2013

Bianchi Type VI0 inflationary cosmological model with flat potential in General Relativity, is investigated. To get the deterministic solution in terms of cosmic time t, we assume that σ (shear) is proportional to expansion (θ) where [Formula: see text] Thus [Formula: see text], leads to A = Bn where A and B are metric potentials and n is a constant. We find that spatial volume increases with time. Hence inflationary scenario exists in the model. Since [Formula: see text] in general. Thus the model represents anisotropic universe throughout. However, if [Formula: see text] then the model isotropizes. This result matches with astronomical observations. The model represents decelerating and late time acceleration which matches with recent astronomical observations Riess et al. [29], Perlmutter et al. [30]. The model has Point Type singularity at [Formula: see text] (MacCallum [31]). The rate of Higg’s field (φ) decreases with time.
SYNTHESIS AND CHARACTERIZATION OF Al DOPED ZnO NANOPARTICLES
Authors: KHAN WASI , KHAN Z. A. , SAAD A. A. , SHERVANI S. , SALEEM A. , NAQVI A. H.
Published: May 2013

Undoped and Al-doped ZnO (AZO) nanoparticles (NPs) have been successfully synthesized by the simple sol-gel method. The NPs have been characterized by a number of techniques as x-ray diffraction (XRD), UV-visible spectroscopy and scanning electron microscopy (SEM) at room temperature for 0%, 0.5%, 1% and 2% of Al concentration. The structural characteristics were examined using XRD and SEM with EDS. XRD analysis reveals that all samples crystallizes in polycrystalline nature with wurtzite lattice and exhibit no other impurity phase. The average crystallite size decreases with increase in Al concentration. The absorption spectra indicate increase in optical energy gap (Eg) with increase in Al ion doped into the ZnO lattice site.
CONVERSION OF IMPULSE VOLTAGE GENERATOR INTO STEEP WAVE IMPULSE TEST-EQUIPMENT
Authors: KHAN MOHAMMED ZAID , TANWAR SURENDER SINGH , DAYAMA RAVINDRA , CHOUDHARY RAHUL RAJ , MANGAL RAVINDRA
Published: May 2013

This paper demonstrates the alternative measures to generate the Steep wave impulse by using Impulse Voltage Generator (IVG) for high voltage testing of porcelain insulators. The modification of IVG by incorporating compensation of resistor, inductor, and capacitor has been achieved and further performance of the modified system has been analyzed by applying the generated lightning impulse and analyzing the electrical characteristics of impulse waves under standard lightning and fast rise multiple lightning waveform to determine the effect to improve rise time. The advantageous results have been received and being reported such as increase in overshoot compensation, increase in capacitive and inductive load ranges. Such further reduces the duration of oscillations of standard impulse voltages. The reduction in oscillation duration of steep front impulse voltages may be utilized in up gradation of Impulse Voltage Generator System. Stray capacitance could further be added in order to get the minimized difference of measurement between simulation and the field establishment.
THERMODYNAMIC BEHAVIOUR OF HYPERSENSITIVE TRANSITION OBSERVED IN SOME THULIUM ION DOPED SYSTEMS
Authors: VYAS MAHENDRA , PUROHIT PRAVEEN , PRAJAPAT GARIMA , PANDEY H. K.
Published: May 2013

The Tm(III) doped systems with various ligands studied with respect to hypersensitive transition. The spectroscopic data for hypersensitive transition have been correlated with the thermodynamic parameters. The thermodynamic parameters include thermodynamic efficiency and partition function of the transition.
DEVELOPMENT OF NANOFLUIDS AS LUBRICANT TO STUDY FRICTION AND WEAR BEHAVIOR OF STAINLESS STEELS
Authors: SAHOO RASHMI RANJAN , BHATTACHARJEE SANTU , DAS TUHIN
Published: May 2013

A number of nanofluids have been prepared to study the effect of lubrication properties of nanofluids on stainless steels taking Kaolin and Boron Nitride (BN) as the lubricant particles and Sodium Dodecyl Sulfate (SDS), Cetyl Trimethyl Ammonium Bromide (CTAB), Sodium Hexa Meta Phosphate (SHMP) as dispersants in the same liquid medium i.e. water. A pin on disc tribometer is being used to access the tribological behaviour of the prepared nanofluids. The particle size of these particle dispersions are examined with a nanoparticle size analyzer. It has been found that the use of dispersants significantly control the particle size and tribological behavior of the nanofluids as for Boron Nitride particle with Sodium Dodecyl Sulfate (SDS) as dispersant has got a very low value of coefficient of friction being equal to 0.142 while without dispersant the value is 0.498. Similarly, in case of Kaolin water with SDS as dispersant the value of coefficient of friction obtained is 0.161 and without dispersant it is 0.333. Sodium Dodecyl Sulfate (SDS) as dispersant has resulted a very low coefficient of friction compared to other dispersants tested even though it doesn’t always assure a least particle size. The role of SDS in yielding the lowest friction has pursued significant attention for further investigation.
ELECTRON PHONON INTERACTION IN K-DOPED (10,10) CARBON NANOTUBE
Authors: UPADHYAY P. K. , NAGAR A. K.
Published: May 2013

Depending on their strength, the electron–phonon interactions in systems involving electron moving in deformable lattice of atoms can become very important for the dynamics of such systems and may lead to some very interesting phenomena eg. quasiparicle self trapping. We consider Metallic Carbon Nanotube with an excess electron. We choose 2- dimensional hexagonal lattice to be periodic and to have a large extension in one direction and a small extension in the other direction. We study the Modified Nonlinear Schrodinger Equation in Carbon Nanotube (10,10) where the modified term arises due to interaction between excess electron field and lattice distortion and gives stabilization to the solution. This interaction symbolizes strength of nonlinearity in the system. We solved this equation numerically using cylindrical coordinates and found that solutions depend crucially on electron- phonon interaction coefficient.
SOLITON PULSE ANALYSIS IN GaInP PHOTONIC CRYSTAL WAVEGUIDE
Authors: UPADHYAY P. K. , NAGAR A. K.
Published: May 2013

Solitons are nonlinear waves that remain invariant as they propagate. Precise control of dispersion and nonlinear effects govern soliton propagation. In recent years Photonic crystals (PhCs) have attracted a great deal of attention due to the facility to engineer and enhance both their nonlinear and dispersive effects. In this article we show soliton pulse analysis in GaInP Photonic Crystal Waveguides using AUTO bifurcation analysis tool. We have demonstrated pulse compression at moderately slow velocities in GaInP Photonic Crystal Waveguides. This is enabled by the enhanced self phase modulation and strong negative group velocity dispersion in the Photonic Crystal Waveguides.
LASER INDUCED NONLINEAR OPTICAL RESPONSE OF CARBON NANOTUBES DEPOSITED ON A DIELECTRIC SUBSTRATE
Authors: BISSA SHIVANGI , NARUKA PREETI
Published: May 2013

In the present paper, the nonlinear response of carbon nanotubes has been investigated by using the dielectric constants of these nanotubes evaluated by using the Maxwell-Garnett Effective Medium Theory. SWNT’s deposited on the tip of a dielectric substrate show a drastic change in reflectance and transmittance of the incident laser light due to change in their nonlinearity and optical constants. This property may be further used for developing all-optical switching devices.
LATTICE DYNAMICAL INVESTIGATIONS FOR RAMAN AND THE INFRARED FREQUENCIES OF Cs2HgCl4
Authors: GARG SHAVEEN , SINHA M. M. , GUPTA H. C.
Published: May 2013

A short-range force constant model has been applied in investigating the Raman and infrared modes in insulating Cs2HgCl4 in orthorhombic phase having space group Pnam using normal coordinate analysis. Calculations on zone centre phonons have been made with twelve stretching and three bending force constants. The calculated Raman and infrared wave numbers are in good agreement with the available experimental results. The potential energy distribution has also been investigated for determining the significance of contribution from each force constant towards the Raman and the infrared wave numbers.
LASER IN CERAMICS PROCESSING
Authors: LAL BAJRANG , JAIN PANKAJ
Published: May 2013

LASER, an acronym for Light Amplification by Stimulated Emission of Radiation have unique properties, Which make it differ from ordinary light such as it is highly coherent, monochromatic, negligible divergence and scattering loss and a intense beam of electromagnetic radiation or light. It also occur in a wide range of wavelength/frequency (from Ultraviolet to Infrared), energy/power and beam-mode/configurations ; Due to these unique properties, it have use in wide application of ceramic processing for industrial manufacturing, fabrication of electronic circuit such as marking, serializing, engraving, cutting, micro-structuring because laser only produces localized heating, without any contact and thermal stress on the any part during processing. So there is no risk of fracturing that occurs during mechanical sawing and also reduce Cost of processing. The discussion in this paper highlight the application of laser in ceramics processing.
ON REDUCIBILITIES OF CERTAIN TRIPLE HYPERGEOMETRIC SERIES HA AND HC OF SRIVASTAVA
Authors: ALI SHOUKAT
Published: May 2013

The aim of this research paper is to consider some very interesting reducible cases of HA and HC introduced by Srivastava who actually noticed the existence of three additional complete triple hypergeometric functions HA , HB and HC of the second order in the course of an extensive investigation of Lauricella’s fourteen hypergeometric functions of three variables. The results are derived with the help of known classical summation theorems recently added in the literature due to Lavoie et al. Several results obtained earlier by Kim et al. follow special cases of our main findings.
A TRANSFORMATION FORMULA FOR THE KAMPÉ DE FÉRIET FUNCTION
Authors: ALI SHOUKAT
Published: May 2013

In 1997, Exton have obtained an interesting case of the transformation of Kampé de Fériet function by employing classical Watson’s theorem on the sum of a 3F2 .

The aim of this research note is to obtain one result contiguous to that of Exton.
STUDY OF ELLIPTIC FLOW WITH PSEUDO RAPIDITY
Authors: BHARDWAJ SUDHIR , KALA PANKAJ , AGNIHOTRI ASHISH
Published: May 2013

The relativistic heavy ion collisions experiments are working on the different energies. In this paper we will study elliptic flow variation with pseudo rapidity at for charge pions and photons using HIJING event generator models. Elliptic flow is a signal in search of quark gluon plasma.
STUDY OF ELLIPTIC FLOW AT RHIC ENERGIES
Authors: BHARDWAJ SUDHIR , SOMANI AJIT K , AGNIHOTRI ASHISH
Published: May 2013

The relativistic heavy ion collisions are the experiment which is working on the different energies 200 and 62.4 GeV. In this paper we will study elliptic flow variation with Impact Parameter at above mentioned energies using HIJING event generator models. Elliptic flow is a signal in search of quark gluon plasma.
LIQUID CRYSTALS AND APPLICATIONS OF CHLOSTERIC LIQUID CRYSTAL IN LASER
Authors: SONI SURESH , BISHNOI DIMPLE DHARNIYA , SONI SUBHASH , RAMSWROOP
Published: May 2013

Liquid crystals are a state of matter intermediate between that of a crystalline solid and an isotropic liquid. They possess many of the mechanical properties of a liquid, e.g. - high fluidity, inability to support shear, formation, and coalescence of droplets. At the same time they are similar to crystals in that they exhibit anisotropy in their optical, electrical, and magnetic properties. We discuss some physical properties of nematic, cholesteric, and smectic liquid crystals (Specially focused on cholesteric) and some applications in laser due to Cholesteric Liquid Crystal’s resonant cavity which formed spontaneously and intrinsically, in the form of self-assembled chiral nematic helix.
DESIGN OF A SAMPLE HOLDER FOR LOW TEMPERATURE ELECTRICAL CONDUCTIVITY MEASUREMENTS
Authors: SINGH YADUNATH
Published: May 2013

Both DC and AC electrical conductivity of materials provide a number of valuable informationon the nature of current carriers, 3-D effects, scattering by defects and impurities, formation of CDW, soliton propagation, non – linear and switching phenomenon and other characters pertaining to these compounds. These measurements are therefore carried out over a wide range of temperature, pressure, electric fields and impurity concentrations. Besides these, the low temperature studies of the materials are performed to determine Optical and Magnetic properties and etc. Therefore, a suitable sample holder is required to perform these studies with low temperature variations. In this paper, we report a design of such a suitable and simple sample holder, which can work up to liquid nitrogen temperature (77 K). This model is easy to fabricate, low cost, more efficient with less wastage in terms of liquid gases than other models. This model can be used for both low temperature dependent electrical conductivity at ambient pressure and clamped high pressure measurements within the given range
ELECTRICAL RESISTIVITY MEASUREMENTS: A REVIEW
Authors: SINGH YADUNATH
Published: May 2013

World-wide interest on the use of ceramic materials for aerospace and other advanced engineering applications, has led to the need for inspection techniques capable of detecting unusually electrical and thermal anomalies in these compounds. Modern ceramic materials offer many attractive physical, electrical and mechanical properties for a wide and rapidly growing range of industrial applications; moreover specific use may be made of their electrical resistance, chemical resistance, and thermal barrier properties. In this review, we report the development and various techniques for the resistivity measurement of solid kind of samples.
FUZZY GOAL PROGRAMMING VS ORDINARY FUZZY PROGRAMMING APPROACH FOR MULTI OBJECTIVE PROGRAMMING PROBLEM
Authors: LACHHWANI KAILASH
Published: May 2013

This paper presents the comparison between two solution methodologies Fuzzy Goal Programming (FGP) and ordinary Fuzzy Programming (FP) for multiobjective programming problem. Ordinary fuzzy programming approach is used to develop the solution algorithm for multiobjective functions which works for the minimization of the perpendicular distances between the parallel hyper planes at the optimum points of the objective functions. Suitable membership function is defined as the supremum perpendicular distance and a compromise optimum solution is obtained as a result of minimization of supremum perpendicular distance. Whereas, In the FGP model formulation, firstly the objectives are transformed into fuzzy goals (membership functions) by means of assigning an aspiration level to each of them and suitable membership function is defined for each objectives. Then achievement of the highest membership value of each of fuzzy goals is formulated by minimizing the negative deviational variables.
THE SPECTRUM OF RANDOM KERNEL MATRICES: UNIVERSALITY RESULTS FOR ROUGH AND VARYING KERNELS
Authors: DO YEN , VU VAN
Published: May 2013

We consider random matrices whose entries are [Formula: see text] or f(‖Xi – Xj‖2) for iid vectors Xi ∈ ℝp with normalized distribution. Assuming that f is sufficiently smooth and the distribution of Xi's is sufficiently nice, El Karoui [The spectrum of Kernel random matrices, Ann. Statist.38(1) (2010) 1–50, MR 2589315 (2011a.62187)] showed that the spectral distributions of these matrices behave as if f is linear in the Marčhenko–Pastur limit. When Xi's are Gaussian vectors, variants of this phenomenon were recently proved for varying kernels, i.e. when f may depend on p, by Cheng–Singer [The spectrum of random inner-product Kernel matrices, preprint (2012), arXiv:1202.3155 [math.PR]]. Two results are shown in this paper: first, it is shown that for a large class of distributions the regularity assumptions on f in El Karoui's results can be reduced to minimal; and second, it is shown that the Gaussian assumptions in Cheng–Singer's result can be removed, answering a question posed in [The spectrum of random inner-product Kernel matrices, preprint (2012), arXiv:1202.3155 [math.PR]] about the universality of the limiting spectral distribution.
Morphology andIn VitroBehavior of Electrospun Fibrous Poly(D,L-lactic acid) for Biomedical Applications
Authors: Inami Toshihiro , Tanimoto Yasuhiro , Ueda Masayuki , Shibata Yo , Hirayama Satoshi , Yamaguchi Masaru , Kasai Kazutaka
Published: May 2013

This work describes the fabrication, optimization, and characterization of electrospun fibrous poly(D,L-lactic acid) (PDLLA) for biomedical applications. The influences of the polymer concentration of the electrospinning solution (5, 10, or 15 wt%) and the solution flow rate (0.1, 0.5, 1.0, or 2.0 mL/h) on the morphology of the obtained fibrous PDLLA were evaluated. Thein vitrobiocompatibility of two types of PDLLA, ester terminated PDLLA (PDLLA-R) and carboxyl terminated PDLLA (PDLLA-COOH), was evaluated by monitoring apatite formation on samples immersed in Hanks’ balanced salt (HBS) solution. 15 wt% polymer solution was the most beneficial for preparing a fibrous PDLLA structure. Meanwhile, no differences in morphology were observed for PDLLA prepared at various flow rates. Apatite precipitate is formed on both types of PDLLA only 1 day after immersion in HBS solution. After 7 days of immersion, PDLLA-COOH showed greater apatite formation ability compared with that of PDLLA-R, as measured by thin-film X-ray diffraction. The results indicated that the carboxyl group is effective for apatite precipitation in the body environment.
Chaotic and Subharmonic Motion Analysis of Floating Ring Gas Bearing System by Hybrid Numerical Method
Authors: Wang Cheng-Chi , Yau Her-Terng , Wang Chi-Chang
Published: May 2013

This paper studies the nonlinear dynamic behaviors including chaotic, subharmonic, and quasi-periodic motions of a rigid rotor supported by floating ring gas bearing (FRGB) system. A hybrid numerical method combining the differential transformation method and the finite difference method used to calculate pressure distribution of FRGB system and rotor orbits. The results obtained for the orbits of the rotor center are in good agreement with those obtained using the traditional finite difference approach. Moreover, the hybrid method avoids the numerical instability problem suffered by the finite difference scheme at low values of the rotor mass and computational time-step. Moreover, power spectra, Poincaré maps, bifurcation diagrams and Lyapunov exponents are applied to examine the nonlinear dynamic response of the FRGB system over representative ranges of the rotor mass and bearing number, respectively. The results presented summarize the changes which take place in the dynamic behavior of the FRGB system as the rotor mass and bearing number are increased and therefore provide a useful guideline for the bearing system.
Value Sharing Results forq-Shifts Difference Polynomials
Authors: Liu Yong , Cao Yinhong , Qi Xiaoguang , Yi Hongxun
Published: May 2013

We investigate the zero distribution ofq-shift difference polynomials of meromorphic functions with zero order and obtain some results that extend previous results of K. Liu et al.
High Folic Acid Intake during Pregnancy Lowers Body Weight and Reduces Femoral Area and Strength in Female Rat Offspring
Authors: Huot Pedro S. P. , Dodington David W. , Mollard Rebecca C. , Reza-López Sandra A. , Sánchez-Hernández Diana , Cho Clara E. , Kuk Justin , Ward Wendy E. , Anderson G. Harvey
Published: May 2013

Rats fed gestational diets high in multivitamin or folate produce offspring of altered phenotypes. We hypothesized that female rat offspring born to dams fed a gestational diet high in folic acid (HFol) have compromised bone health and that feeding the offspring the same HFol diet attenuates these effects. Pregnant rats were fed diets with either recommended folic acid (RFol) or 10-fold higher folic acid (HFol) amounts. Female offspring were weaned to either the RFol or HFol diet for 17 weeks. HFol maternal diet resulted in lower offspring body weights (6%,P=0.03) and, after adjusting for body weight and femoral length, smaller femoral area (2%,P=0.03), compared to control diet. After adjustments, HFol pup diet resulted in lower mineral content (7%,P=0.01) and density (4%,P=0.002) of lumbar vertebra 4 without differences in strength. An interaction between folate content of the dam and pup diets revealed that a mismatch resulted in lower femoral peak load strength (P=0.01) and stiffness (P=0.002). However, the match in folate content failed to prevent lower weight gain. In conclusion, HFol diets fed to rat dams and their offspring affect area and strength of femurs and mineral quantity but not strength of lumbar vertebrae in the offspring.
Altered Responses to Cold Environment in Urocortin 1 and Corticotropin-Releasing Factor Deficient Mice
Authors: Chaker Bayan , Samra Tareq A. , Datta Nabanita S. , Abou-Samra Abdul B.
Published: May 2013

We examined core body temperature (CBT) of urocortin 1 (UCN1) and corticotropin releasing factor (CRF) knockout (KO) mice exposed to 4°C for 2 h. UCN1KO mice showed higher average CBT during cold exposure as compared to WT. The CBT of male and female WT mice dropped significantly to34.1 ± 2.4and34.9 ± 3.1 C at 4°C, respectively. In contrast, the CBT of male and female UCN1KO mice dropped only slightly after 2 h at 4°C to36.8 ± 0.7and38.1 ± 0.5 C, respectively. WT female and male UCN1KO mice showed significant acclimatization to cold; however, female UCN1KO mice did not show such a significant acclimatization. CRFKO mice showed a dramatic decline in CBT from38.2 ± 0.4at 22°C to26.1 ± 9.8at 4°C for 2 h. The CRF/UCN1 double KO (dKO) mice dropped their CBT to32.5 ± 4.0after 2 h exposure to 4°C. Dexamethasone treatment prevented the decline in CBT of the CRFKO and the dKO mice. Taken together, the data suggest a novel role for UCN1 in thermoregulation. The role of CRF is likely secondary to adrenal glucocorticoids, which have an important regulatory role on carbohydrate, fat, and protein metabolism.
Osteosarcoma: Evolution of Treatment Paradigms
Authors: Jaffe Norman , Puri Ajay , Gelderblom Hans
Published: May 2013

This paper reviews the contribution of chemotherapy in the conquest of osteosarcoma. It discusses how the treatment of osteosarcoma has evolved over the last five decades, resulting in a more than fivefold increase in survival. Though the initial improvements in survival were dramatic, essentially there has been no change in the outlook for this disease over the past 30 years. The paper also highlights the necessity of a multidisciplinary approach to combat this disease and stresses the need to explore newer treatment agents in order to build on the lessons learnt from the past while striving to achieve greater levels of success.
Design a Bioamplifier with High CMRR
Authors: Hsiao Yu-Ming , Shiau Miin-Shyue , Li Kuen-Han , Hou Jing-Jhong , Hsu Heng-Shou , Wu Hong-Chong , Liu Don-Gey
Published: May 2013

A CMOS amplifier with differential input and output was designed for very high common-mode rejection ratio (CMRR) and low offset. This design was implemented by the 0.35 μm CMOS technology provided by TSMC. With three stages of amplification and by balanced self-bias, a voltage gain of 80 dB with a CMRR of 130 dB was achieved. The related input offset was as low as 0.6 μV. In addition, the bias circuits were designed to be less sensitive to the power supply. It was expected that the whole amplifier was then more independent of process variations. This fact was confirmed in this study by simulation. With the simulation results, it is promising to exhibit an amplifier with high performances for biomedical applications.
Hyperthermia versus Oncothermia: Cellular Effects in Cancer Therapy
Authors: Szigeti Gyula P. , Hegyi Gabriella , Szasz Olivér
Published: May 2013

Hyperthermia means overheating of the living object completely or partly. Hyperthermia, the procedure of raising the temperature of a part of or the whole body above the normal for a defined period of time, is applied alone or as an adjunctive with various established cancer treatment modalities such as radiotherapy and chemotherapy. The fact that is the hyperthermia is not generally accepted as conventional therapy. The problem is its controversial performance. The controversy is originated from the complications of the deep heating and the focusing of the heat effect. The idea of oncothermia solves the selective deep action on nearly cellular resolution. We would like to demonstrate the force and perspectives of oncothermia as a highly specialized hyperthermia in clinical oncology. Our aim is to prove the ability of oncothermia to be a candidate to become a widely accepted modality of the standard cancer care. We would like to show the proofs and the challenges of the hyperthermia and oncothermia applications to provide the presently available data and summarize the knowledge in the topic. Like many early-stage therapies, oncothermia lacks adequate treatment experience and long-range, comprehensive statistics that can help us optimize its use for all indications.
Active MMW/Terahertz Security System Based on Bessel Beams
Authors: Minin Igor , Minin Oleg
Published: May 2013

The novel concept of the security system based on THz Bessel beams is offered. The system is based on a novel THz diffractive optics for scanning the person (without the application of THz laser) and on a sensitive scheme for the detection of the reflected and scattered THz radiation. The development of enabling technology, namely, sensitive detector arrays and Millimeter wave/THz diffractive optics, will allow building compact, easy-to-use millimeter wave/THz imaging systems without expensive cost THz laser. The scanning properties of diffractive optics for Bessel beam are investigated.
Bacillus cereus in Infant Foods: Prevalence Study and Distribution of Enterotoxigenic Virulence Factors in Isfahan Province, Iran
Authors: Rahimi Ebrahim , Abdos Fahimeh , Momtaz Hassan , Torki Baghbadorani Zienab , Jalali Mohammad
Published: May 2013

This study was carried out in order to investigate the presences of Bacillus cereus and its enterotoxigenic genes in infant foods in Isfahan, Iran. Overall 200 infant foods with various based were collected and immediately transferred to the laboratory. All samples were culture and the genomic DNA was extracted from colonies with typical characters of Bacillus cereus. The presences of enterotoxigenic genes were investigated using the PCR technique. Eighty‐four of two hundred samples (42%) were found to be contaminated with B. cereus with a ranges of 3 × 101–9.3 × 101 spore per gram sample. Totally, entFM had the highest (61.90%) incidences of enterotoxigenic genes while hblA had the lowest (13.09%) incidences of enterotoxigenic genes. Overall, 6.7% of B. cereus isolates had all studied enetrotoxigenic genes while 25.5% of B. cereus strains had all studied enetrotoxigenic genes expectance bceT gene. Thisstudyisthe first prevalence report of B. cereus and its enterotoxigenic genes in infant foods in Iran. Results showed that the infant food is one of the main sources of enterotoxigenic genes of B. cereus in Iran. Therefore, the accurate food inspection causes to reducing outbreak of diseases.
Mitochondrial Fusion Proteins and Human Diseases
Authors: Ranieri Michela , Brajkovic Simona , Riboldi Giulietta , Ronchi Dario , Rizzo Federica , Bresolin Nereo , Corti Stefania , Comi Giacomo P.
Published: May 2013

Mitochondria are highly dynamic, complex organelles that continuously alter their shape, ranging between two opposite processes, fission and fusion, in response to several stimuli and the metabolic demands of the cell. Alterations in mitochondrial dynamics due to mutations in proteins involved in the fusion-fission machinery represent an important pathogenic mechanism of human diseases. The most relevant proteins involved in the mitochondrial fusion process are three GTPase dynamin-like proteins: mitofusin 1 (MFN1) and 2 (MFN2), located in the outer mitochondrial membrane, and optic atrophy protein 1 (OPA1), in the inner membrane. An expanding number of degenerative disorders are associated with mutations in the genes encoding MFN2 and OPA1, including Charcot-Marie-Tooth disease type 2A and autosomal dominant optic atrophy. While these disorders can still be considered rare, defective mitochondrial dynamics seem to play a significant role in the molecular and cellular pathogenesis of more common neurodegenerative diseases, for example, Alzheimer’s and Parkinson’s diseases. This review provides an overview of the basic molecular mechanisms involved in mitochondrial fusion and focuses on the alteration in mitochondrial DNA amount resulting from impairment of mitochondrial dynamics. We also review the literature describing the main disorders associated with the disruption of mitochondrial fusion.
On Certain Classes of Convex Functions
Authors: Sim Young Jae , Kwon Oh Sang
Published: May 2013

For real numbersαandβsuch that0≤α<1<β, we denote by𝒦α,βthe class of normalized analytic functions which satisfy the following two sided-inequality:α<ℜ1+zf′′z/f′z<β  z∈𝕌,where𝕌denotes the open unit disk. We find some relationships involving functions in the class𝒦(α,β). And we estimate the bounds of coefficients and solve the Fekete-Szegö problem for functions in this class. Furthermore, we investigate the bounds of initial coefficients of inverse functions or biunivalent functions.
Heat and Mass Transfer with Free Convection MHD Flow Past a Vertical Plate Embedded in a Porous Medium
Authors: Ali Farhad , Khan Ilyas , Shafie Sharidan , Musthapa Norzieha
Published: May 2013

An analysis to investigate the combined effects of heat and mass transfer on free convection unsteady magnetohydrodynamic (MHD) flow of viscous fluid embedded in a porous medium is presented. The flow in the fluid is induced due to uniform motion of the plate. The dimensionless coupled linear partial differential equations are solved by using Laplace transform method. The solutions that have been obtained are expressed in simple forms in terms of elementary functionexp(·)and complementary error functionerfc(·). They satisfy the governing equations; all imposed initial and boundary conditions and can immediately be reduced to their limiting solutions. The influence of various embedded flow parameters such as the Hartmann number, permeability parameter, Grashof number, dimensionless time, Prandtl number, chemical reaction parameter, Schmidt number, and Soret number is analyzed graphically. Numerical solutions for skin friction, Nusselt number, and Sherwood number are also obtained in tabular forms.
Yoga and Mindfulness as Therapeutic Interventions for Stroke Rehabilitation: A Systematic Review
Authors: Lazaridou Asimina , Philbrook Phaethon , Tzika Aria A.
Published: May 2013

Aim. This paper reports a systematic review and critical appraisal of the evidence on the effectiveness of behavioral therapies such as yoga and mindfulness practices for stroke rehabilitation.Background. The experience of stroke can have a negative impact on both psychological and physical health and on quality of life. Yoga and relevant practices are promising therapies that have been used with patients with a variety of conditions. In order to draw conclusions on effectiveness for stroke patients, the evidence requires systematic assessment.Methods. A comprehensive search of major biomedical and complementary medicine databases was conducted. Relevant research was categorized by study type and appraised according to study design.Results. Five randomized controlled clinical trials and four single case studies were found. Additionally, one qualitative research study was identified. Studies reported positive results, including improvements in cognition, mood, and balance and reductions in stress. Modifications to different yoga practices make comparison between studies difficult, and a lack of controlled studies precludes any firm conclusions on efficacy.Conclusion. Yoga and mindfulness could be clinically valuable self-administered intervention options for stroke rehabilitation. Further research is needed to evaluate these specific practices and their suitability in stroke rehabilitation.
Differences in Plasma Cytokine Levels between Elite Kayakers and Nonathletes
Authors: Borges G. F. , Rama L. , Pedreiro S. , Alves F. , Santos A. , Massart A. , Paiva A. , Teixeira A. M.
Published: May 2013

Regular moderate exercise has been shown to have anti-inflammatory effects that help prevent several chronic diseases. However, the effects of chronic training an elite athletes have not been the focus of much research. This study aimed to determine whether there were differences in cytokine levels (IL-1β, IL-1ra, IL-6, IL-10, IL-18, IFN-γ, and TNF-α) in circulating peripheral blood (PB) between elite kayakers and nonathletes. Subjects were 13 elite male kayakers, aged20.0±3years, with average body mass of75.0±7.9 kg and177.3±7.1 cm height and with aVO2maxof58.3±7.8 mL·kg−1·min−1. The nonathletes were 7 men, aged18.2±1.1years, body mass of81.3±13.8 kg, and171.9±4.5 cm height. Blood samples were collected after six weeks of offtraining and before the start of a new training season. PB leukocyte populations were determined by flow cytometry. Cytokine levels were quantified by ELISA. When nonathletes were compared with the kayakers, the latter exhibited lower plasma concentrations of IL-1β, IL-18, and IFN-γas well as a lower concentration of IL-1ra. Positive correlations between IL-18 and B cells in the athletes were also found. These results seem to reinforce the anti-inflammatory role of regular training.