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Abstract This paper presents a maiden alternative approach to the cost based allocation over the transmission network for individual generators associated with the system. A modified method is proposed by which the proportion of power going from an individual generator to the loads, and to the rest of the transmission network can be traced in a grid system. Also, the revenue collected from the customer side for all associated producers separately can be determined. The developed technique has been experimented successfully on a 39-bus New England Power System and to validate the method, the outcomes of the projected algorithm of the test system are compared with the power flow solution obtained by using the sequential quadratic programming method. The comparative analysis reveals that the results obtained from both the methods are nearly the same under different loading conditions, proving the accuracy and robustness of the proposed method. [ABSTRACT FROM AUTHOR]

Very intense and highly dynamic eastward and westward currents flowing in the auroral ionosphere are traditionally monitored by the auroral electrojet indices – AU and AL , respectively. In this study we show that on occasions of intense magnetic activity, entire auroral oval could be dominated by the westward flowing currents, which lead to depression not only in AL index but also in supposedly positive AU index. During negative AU intervals, there could be up to ∼ 20 % underestimation of the total maximum intensity of the auroral electrojet represented by AE index ( defined as AU - AL ). A detailed investigation of a well-studied extremely intense event of 24 August 2005 has been carried out. Global prevalence of the westward auroral electrojet was clearly observed at the auroral latitudes during the unusually intense substorm ( AL ∼ - 4000 nT) on the day. Moreover, along the noon meridian westward electrojet appeared in the auroral region whereas eastward electrojet shifted towards lower latitudes. This paper emphasizes that intense substorms are represented better by AL index than AE index. [ABSTRACT FROM AUTHOR]

Abstract: Magnetic data from a newly commissioned Indian Antarctic station Bharati (corrected geomagnetic (CGM) coordinates 74.7°S, 97.2°E) and closely-spaced IMAGE chain observatories (∼100° magnetic meridian in Northern hemisphere) has been analyzed to study the climatology of substorms which were localized poleward of the standard auroral oval. We considered four austral summers (year 2007–2010) when data from Bharati was available. Several very high latitude substorms were observed in this duration when the solar activity remained unexpectedly low for a long time. Various features of very high latitude substorms, e.g., local time dependence, interplanetary state, hemispherical asymmetry and their nightside low latitude signatures are examined. Events studied here, suggested the following properties of substorms occurring at very high latitudes: (1) maximum occurrence was observed near magnetic midnight (21:00–02:00 MLT). (2) In contradiction to earlier reports, many substorms were observed even during negative IMF Bz condition. In addition, majority of substorms occurred during low or moderate solar wind streams. (3) Magnetic signatures were often pronounced in the winter hemisphere. (4) Even if widely used standard AE indices fail to monitor very high latitude substorms, their low latitude signatures are often evident. [Copyright &y& Elsevier]

Abstract: We show examples of long period Pc5 magnetic field pulsations near field-aligned current (FAC) regions in the high-latitude magnetosphere, observed by INTERBALL-Au, and coordinated with POLAR, GOES-9 and ground-based observations during 11 January and 11 April 1997. Identification of corresponding magnetosphere regions and subregions is provided by electrons and protons in the energy-range of 0.01–100keV measured onboard the spacecraft. The ULF Pc5 wave occurrence is observed in both upward and downward FACs. A fairly good correlation is demonstrated between these ULF Pc5 waves and the consecutive injection of magnetosheath low energy protons. The constancy of the observed frequency peak at 1.8mHz during quite unsteady solar wind pressure conditions could be reconciled with the surface wave mode model. The 3.1mHz peak location area probably resembles field-line fluctuations with an interesting appearance of poloidal mode oscillation. It is suggested that the 1.3mHz wave and its harmonic 2.6mHz represent global compressional oscillations. [Copyright &y& Elsevier]

A prototype chip fabricated in 130 nm CMOS technology, designed to extract maximum power from a thermoelectric generator (TEG) is presented. In the measurements, the TEG is modelled by a voltage source (VTEG) with a series resistance of 5 Ω. The prototype is fully electric, starts from VTEG = 50 mV and it can extract 60% (at 50 mV) to 65% (at 200 mV) of the available power. Also by using present circuit schematic, an improved transient response of 3 ms (at 50 mV) and startup voltage of 50 mV is achieved. [ABSTRACT FROM AUTHOR]

Abstract: An effort was made to analyze the effect of in vitro stimulation on macrophages using killed Shigella dysenteriae type-1 (KSD1) coupled with anti-Interferon Gamma (anti-IFN-γ) antibody. The stimulated macrophages were co-cultured with primed or non-primed T-cells from Shigella infected patients. T-cell cultures were also established by co-culturing KSD1 coupled with or without PHA stimulated macrophages. Emulsified KSD1 coupled with anti-IFN-γ antibody was found to act as a potent immunogen, inducing the release of Th1 cytokine from primed T-cells cultured in acute stage of the disease. It was observed that the levels of IFN-γ and IL-2 production rather than IL-4 and IL-6 were increased as the disease became more severe. On comparison, the subsequent values of IL-6, IFN-γ, IL-4 and IL-2 were found to be less significant in healthy primed T-cell cultures. This was also associated with a substantial production of superoxide ions (O2 −), which probably inhibits the colonization of intracellular Shigella due to the presence of anti-IFN-γ antibodies. On the other hand KSD1 with or without PHA failed to induce such responses. The above findings reflect that in the presence of anti-IFN-γ antibody, KSD1 acts as a potential immunogen for eliciting cellular immunity against shigellosis. [Copyright &y& Elsevier]

Medium-pore SAPO-11 and SAPO-31 molecular sieves were synthesized from aqueous and non-aqueous (ethylene glycol) media. All the samples were characterized by XRD, SEM, N2 adsorption (BET analysis), TGA-DTA, pyridine-TPD, 27Al MAS-NMR, and 29Si MAS-NMR. The samples synthesized from non-aqueous medium possess higher acidity due to higher substitution of Si4+ at P5+ sites and less silica island formation, as evidenced from 29Si MAS-NMR spectra. It is possible to incorporate more silicon in the samples by synthesis in ethylene glycol medium. The SAPOs synthesized from non-aqueous medium show higher activity for the isomerization of m-xylene. [Copyright &y& Elsevier]

Ti-containing MCM-41 supports were prepared by: (a) hydrothermal crystallization; (b) post-synthesis grafting; and (c) two-step Ti incorporation—hydrothermal incorporation followed by post-synthesis grafting. XRD revealed little change in crystallinity and long range order of MCM-41 phase after Ti incorporation by different methods. UV-Vis spectra show the presence of tetrahedral Ti sites at lower Ti contents (upto 4.5 mol%), but aggregated titania formation could be observed at higher Ti loadings (>4.5 mol%). The samples exhibit surface areas and pore volumes in the mesoporous range. Vapor phase epoxidation of propene using H2 and O2 was carried out over these supports after Au deposition by deposition-precipitation (DP) method. The Ti-MCM-41 supports prepared by two-step Ti incorporation (with up to 4.5 mol% input Ti), which probably have more number of isolated Ti sites, showed higher catalytic activity than Ti-MCM-41 prepared by one-step Ti incorporation method, at comparable propylene oxide selectivities and hydrogen efficiencies. The former catalyst also deactivates more slowly than the latter ones, probably due to a decrease in the number of silanol sites (those responsible for deactivation) due to grafted Ti. [Copyright &y& Elsevier]

Metal phthalocyanine complexes (MPc; M=V, Co and Cu) were encapsulated in zeolite-Y by “in situ ligand synthesis” method and were characterized by chemical and thermal analyses, FT-IR, diffuse reflectance UV–VIS and EPR spectroscopic techniques. The Pc moiety undergoes distortion from square planarity on encapsulation. The studies have provided evidence for the encapsulation of MPc inside the supercages of zeolite-Y. The encapsulated complexes exhibited enhanced phenol hydroxylation activity with H2O2 compared to the “neat” complexes in homogeneous medium. A comparative study has revealed that the activity and product selectivity of the encapsulated complexes can be correlated with the redox potential of the M(n+1)/Mn+ couple of the central metal atom of the encapsulated phthalocyanine. [Copyright &y& Elsevier]

• The relative dominance between IMF and SI in triggering a substorm. • Ground and satellite based analysis of impulse induced substorms. • Solar wind particle injection via viscous interaction during substorms. • Importance of SML-LT index in identifying the triggering agent of substorm onset. • Substorm onset far away from usual midnight. During a typical Akasofu-type of substorm, the southward component of IMF Bz is necessary prior to the onset. However, a sudden compression of solar wind, if intense enough, can also sometimes trigger a substorm, and is independent of the IMF orientation. The Akasofu-type substorm and the Impulse-induced substorm may differ in their occurrence mechanism and ground-based observations. This is shown using the initial four substorm events discussed in this paper having distinctly different IMF and sudden impulse conditions. A question then arises is how will these signatures vary when both sudden impulse and a southward component of IMF Bz are present prior to the onset. To account for the same, we analyze two substorm events of 05th April 2010 and 22nd June 2015. The substorm onsets on these days not just coincided with the sudden impulse but also a southward component of IMF Bz was present prior to the onsets. The present study accounts for the similarities and differences among isolated IMF induced substorms, isolated impulse-induced substorms and when both sudden impulse and a southward component of IMF Bz are present. We examined the relative dominance between the two factors in triggering a substorm using ground-based and satellite-based observations. If IMF Bz is near zero, a strong pressure pulse and/or large IMF By can lead to particle precipitation away from the usual midnight. To further ensure whether a pressure pulse or IMF By predominantly influences the substorm onset location, a statistical analysis of isolated substorms will be needed. [ABSTRACT FROM AUTHOR]

Presents an algorithm for dynamic state estimation of power systems. Attempt to model dynamics of power system into the state estimation process; Short-Term Load Forecasting (STLF) as one of the application areas of the Artificial Neural Network (ANN); Dependence of bus voltage variations on load changes.

Presents a method for the reduction of excessive standing phase angle (SPA) difference between two buses via generator rescheduling, subject to the generation limits. Role of system restoration; Shocks that closing of a circuit breaker on a large SPA difference may cause to the power system; Excessive SPA difference across buses that are to be connected by a transmission line.

Our present work is aimed at increasing the degree of graphitization of carbon black during the synthesis stage itself. For this purpose, we used lamp black route to synthesize carbon black via catalytic graphitization using ferrocene as an organometallic additive into the precursor olive oil. Degree of graphitization was estimated using Raman spectroscopy and microstructure was determined using transmission electron microscopy (TEM). We found that the degree of graphitization as quantified by the Raman spectroscopy could be doubled by changing the concentration of ferrocene into the precursor oil. The TEM images show the presence of multi-layer graphenes, a few tens of nanometers large, which were completely absent when no additive was used. It is proposed that iron plays the role of graphitization enhancer as Raman, TEM and X-Ray diffraction (XRD) measurements show the presence of iron compounds in the product. Oxidation of iron catalyst mainly limits further growth of graphitic clusters. Unlabelled Image • Ferrocene/olive oil based synthesis of carbon black (CB) via lampblack route. • Graphitization of CB increased through ferrocene derived iron as catalyst. • I G /I D ratio in Raman spectra of CB increases from 0.31 to 0.49. • XRD shows Graphite/amorphous carbon ratio increases by 2 upon catalyst use. • Multilayered graphene as well as graphitic bamboo-like structures were observed. [ABSTRACT FROM AUTHOR]

Aluminium hydroxide (Al(OH) 3) was prepared by chemical reaction of the Al(NO 3) 3 in alkaline medium. The as-prepared powder was heated in the temperature range 250 °C to 1250 °C for studying the structural phase transformation at different stages of the heat treatment. The synchrotron x-ray diffraction patterns confirmed a structural transformation of Al(OH) 3 through different (Boehmite, γ, θ, δ, and α) polymorphic phases of Al 2 O 3 on increasing the heat treatment temperature. The samples in Boehmite (γ-AlOOH) and α- Al 2 O 3 phases showed Raman active modes, whereas the intermediate (meta-stable) multi-phased structure showed weak Raman active peaks. The analysis of UV–visible spectra of the samples indicated two optical band gap energy values in the high energy range 4.50–4.73 eV and low energy range 3.06–3.84 eV. The voltage dependence of current, capacitance and electrical polarization were recorded to study electrical properties in heat treated samples. The capacitance value, derived from the polarization, showed a usual increasing trend on decreasing the measurement frequency (inverse of the time) of driving electric voltage. The measured electrical polarization in the samples was found to be highly correlated to their electrical conductivity and the results are helpful to understand the role of electrical conductivity on exhibiting the apparently ferroelectric properties in high conductive and low polarizable dielectric oxides. [ABSTRACT FROM AUTHOR]

CdS-PVP nanocomposites grown with various concentrations of Cd + /S − and PVP are studied using Raman and atomic force microscopy mapping on same selected areas. The study shows that CdS nanocrystals are embedded in either a thin-film or spheres of PVP, formation of which depends on relative ratio of Cd + /S − concentration (density of nanocrystals) to PVP. Collapse of PVP from planer matrix to the sphere morphology is correlated with high density of CdS nanocrystals and the attractive interaction between CdS nanocrystals and PVP polymer leading to a co-operative growth mechanism. The understanding developed can be used to control the growth of CdS-PVP nanocomposites with desired properties for optoelectronic device applications. [ABSTRACT FROM AUTHOR]

The vector magnetic field measurements from three satellite constellation, Swarm mission (Alpha ‘Swarm-A’, Bravo ‘Swarm-B’, and Charlie ‘Swarm-C’) during the quiet days (daily ∑Kp ⩽ 10) of the years 2014–2015 are used to study the characteristic features of equatorial electrojet (EEJ). A program is developed to identify the EEJ signature in the X (northward) component of the magnetic field recorded by the satellite. An empirical model is fitted into the observed EEJ signatures separately for both the hemispheres, to obtain the parameters of electrojet current such as peak current density, total eastward current, the width of EEJ, position of the electrojet axis, etc. The magnetic field signatures of EEJ at different altitudes are then estimated. Swarm B and C are orbiting at different heights (separation ∼50 km) and during the month of April 2014, both the satellites were moving almost simultaneously over nearby longitudes. Therefore, we used those satellite passes to validate the methodology used in the present study. The magnetic field estimates at the location of Swarm-C obtained using the observations of Swarm B are compared with the actual observations of Swarm-C. A good correlation between the actual and the computed values (correlation coefficient = 0.98) authenticates the method of analysis. The altitudinal variation of the amplitude and the width of the EEJ signatures are also depicted. The ratio of the total eastward flowing forward to westward return currents is found to vary between 0.1 and 1.0. The forward and return current values in the northern hemisphere are found to be ∼0.5 to 2 times of those in the southern hemisphere, thereby indicating the hemispheric asymmetry. The latitudinal extents of the forward and return currents are found to have longitudinal dependence similar to that of the amplitude and the width of EEJ showing four peak structures. Local time dependence of EEJ parameters has also been investigated. In general, the results are found to be consistent with previous studies. In order to examine the existence of the EEJ associated meridional currents, we have estimated the vertical current density using combination of two satellites separated in longitude. [ABSTRACT FROM AUTHOR]

The doping effects of a small amount of RE (Gd and Ho) atoms at A (La) sites of La 2 NiMnO 6 double perovskite have been studied by preparing the materials using mechanical alloying of oxide powders and thermal treatment (800–1200 °C), and a direct sintering of the oxide powders at 1300 °C. The synchrotron x-ray diffraction patterns have been used to confirm the formation of single (monoclinic) phase or bi-phased lattice structure depending on thermal treatment temperature. The bi-phased samples are consisting of primary monoclinic phase (P 2 1 /n space group) and secondary orthorhombic phase (Pnma space group). The x-ray photoelectron spectroscopy has confirmed the presence of trivalent La, RE ions, and mixed-valence state of Ni and Mn ions in the samples. The existence of bi-phasic lattice structure and mixed-valence state of Ni and Mn ions have determined magnetic properties. The monoclinic phase has shown ferromagnetic Curie point around 280 K, which has been reduced to low temperature by Gd and Ho doping. The orthorhombic phase has shown weak ferro/ antiferromagnetic spin ordering temperature around 150 K. The experimental results in RE doped La 2 NiMnO 6 double perovskite support a strong correlation between lattice structure and magnetic properties, which depend on doping of RE ions at A sites, electronic charge state of Ni and Mn ions, structural phase components and anti-site disorder of Mn/Ni ions at octahedral sites. • Synthesis of Gd/Ho doped La 2 NiMnO 6 by mechanical alloying and solid state sintering. • A detailed analysis of structure, charge state of ions, and heat treatment effects on magnetism. • The heat treatment effect on coexisting monoclinic and orthorhombic phases in the samples. • Role of Ni-O-Mn bond structure and doping effect on ferromagnetic superexchange interactions. • Role of chemical inhomogeneity on bi-phased ferromagnetic properties and short range order. [ABSTRACT FROM AUTHOR]

Abstract: KIT-6 silica with well-ordered 3-D mesoporosity was developed as support for Mo, CoMo and NiMo catalysts. TEM and low-angle XRD analyses were used to ensure that the cubic Ia3d mesostructure is stable after Mo and promoter incorporation. The wide-angle XRD (as well O2-chemisorption analysis) was used to verify MoO3 (and MoS2) dispersion, with crystallite size <40Å. The IR spectral studies were used to determine the nature of Mo species (octahedral and tetrahedral) and their growth with increasing Mo loading. TPR studies were also used to understand the nature of Mo species and their reducibility. A linear correlation was obtained between catalytic activities and oxygen uptakes suggesting that the increase in anion vacancies were responsible for the observed variation of hydrodesulfurization and hydrogenation activities. A comparison with γ-Al2O3 and SBA-15 supported catalysts shows superior activities of KIT-6 supported catalysts which is attributable to 3-D mesopore connectivity resulting in better catalyst dispersion, higher reducibility of Mo, and faster diffusion of reactant and products in the KIT-6 supported catalysts. [Copyright &y& Elsevier]

The low temperature lattice structure and magnetic properties of Co 2.75 Fe 0.25 O 4 ferrite have been investigated using experimental results from synchrotron x-ray diffraction (SXRD), dc magnetization, ac susceptibility, neutron diffraction and neutron depolarization techniques. The samples have been prepared by chemical co-precipitation of the Fe and Co nitrates solution in high alkaline medium and subsequent thermal annealing of the precipitates in the temperature range of 473–1173 K. Rietveld refinement of the SXRD patterns at room temperature indicated two-phased cubic spinel structure for the samples annealed at temperatures 473–873 K. The samples annealed at temperatures 973 K and 1173 K (CF90) have shown single phased lattice structure. Refinement of the neutron diffraction patterns in the measurement temperature range 5–300 K confirmed the antiferromagnetic (AFM) Co 3 O 4 and ferrimagnetic (FIM) Co 2.75 Fe 0.25 O 4 phases for the sample annealed at 873 K and single FIM phase of Co 2.75 Fe 0.25 O 4 for the CF90 sample. Magnetic measurements have shown a non-equilibrium magnetic structure, consisting of high temperature FIM phase and low temperature AFM phase. The magnetic phases are sensitive to magnetic fields, where high temperature phase is suppressed at higher magnetic fields by enhancing the low temperature AFM phase, irrespective of annealing temperature of the samples. • A detailed study is presented on lattice structure and magnetic properties. • Single-phased and two-phased lattice structure are identified in spinel oxide. • Ferrimagnetic properties are enhanced in spinel oxide close to Co 3 O 4. • The effects of AFM and ferrimagnetic clusters are seen in the temperature scale. • Multiple magnetic transitions are observed in no-equilibrium spinel structure. [ABSTRACT FROM AUTHOR]

Hexagonal Sr 0.6 Ba 0.4 MnO 3 (SBMO) follows P 6 3 / mmc symmetry where MnO 6 octahedra are both face-shared (Mn 2 O 9 bioctahedra) and corner-shared via oxygen anion. It undergoes ferroelectric (FE) and antiferromagnetic (AFM) orderings close to the room temperature. Magnetic properties appear to be governed by intricate exchange interactions among Mn4+ ions within and in adjacent Mn 2 O 9 bioctahedra, contingent upon the local structural changes. Calculations based on our model spin-Hamiltonian reveal that the dominant linear AFM fluctuations between the Mn4+ ions of two oxygen-linked bi-octahedra result in short range correlations, manifest as a smooth drop in magnetization below 325 K. Competition between spin-exchange and local-strain is reckoned as responsible for the atypical magneto-electricity, obtained near the room temperature. • An incipient ferroelectric (FE) with magnetic anomaly nearby room temperature. • Improper-FE is owed to the locally-unequal Mn–O bond lengths in the MnO 6 octahedra. • Short range stabilization of dipoles with short range magnetic ordering. • Mn-displacement soft-vibration mode is coupled to the spin ordering in the material. • Frustration involving spin-exchange and local-strain is responsible for the ME. [ABSTRACT FROM AUTHOR]

Abstract Sm 6 UO 12 has been synthesized by urea-combustion method and characterized using synchrotron x-ray source. The compound is found to be in single phase crystallizing in rhombohedral lattice with lattice parameters a = 10.153 Å and c = 9.625 Å. High-pressure experiment at ambient temperature reveals the lattice to be stable up to 27.0 GPa. The bulk modulus of the compound is found to be 157.0 GPa. At higher pressures, reflections broaden out as a result of disorder in the system, leading to amorphization at further higher pressures. High pressure and high temperature (HP-HT) x-ray diffraction studies have been carried out up to 6.0 GPa and 673 K. A softening is seen in the material at HP-HT resulting in lower bulk modulus at high temperature. Volume thermal expansion coefficients are found to be 22 × 10−6 K−1 and 17.7 × 10−6 K−1 in the temperature range 298 K–473 K and 298 K-673 K, respectively. Highlights • The compressibility in RE 6 UO 12 is found to increase along Rare-earth series. • Contrary to temperature effect, a -axis is more rigid under pressure than c -axis. • Disorder in anions followed by that of cations is seen at high pressures. • Decrease in thermal expansion coefficient with respect to pressure is observed. [ABSTRACT FROM AUTHOR]

Abstract Hydroprocessing of neutral lipids extracted from Nannochloropsis sp. algal biomass was studied over sulfided cobalt molybdenum phosphorus/aluminium oxide (CoMoP/Al 2 O 3) catalyst in a batch reactor at 300–375 °C with H 2 at 50–120 bar. A clear light yellowish green product was obtained, containing 6–26% gasoline, 35 50% kerosene, 8–40% diesel, with 10–80% alkanes, 1–10% cycloalkanes, and 5–35% aromatics, with a maximum of 10% char formation in the process. Power law kinetic model was validated with experimental results. A kinetic study shows a pseudo 1st order reaction with respect to the neutral algae lipids oil concentration, with the activation energy for algal oil conversion over CoMoP/Al 2 O 3 catalyst was 14.96 kJ/mol. Activation energies for the formation of diesel (125 kJ/mol) and kerosene (146 kJ/mol) were higher than for the heavy hydrocarbons such as PAH (7 kJ/mol) and alkanes (64 kJ/mol) products. Graphical abstract Image 1 Highlights • Neutral Algal lipids hydrogenation favors at lower pressure (~ 50 bar), however higher pressure (>50 bar) favors cracking. • 50% Kerosene yield was obtained at 375°C Temperature and 120 bar H 2 Pressure over hydrotreatingsulfided CoMoP catalyst. • Petrochemical feedstocks like aromatics (35%) and cycloalkanes (10%) form by hydroconversion of Nannochloropsis sp. algae. • The activation energy for the conversion of algae oil was 14.96 KJmol over CoMoP/Al 2 O 3 catalyst. [ABSTRACT FROM AUTHOR]

Abstract We present an in-depth study on the structure and magnetic properties of a novel layered oxide, Ca 2 Fe 0.875 Cr 0.125 GaO 5. Structural studies from laboratory X-ray diffraction, synchrotron powder X-ray diffraction and neutron powder diffraction reveal that the compound crystallizes in an orthorhombic Brownmillerite phase with Pnma space group having Fe/Cr – octahedral layers and Ga – tetrahedral layers with around 9.0% of Fe occupying tetrahedral sites. The temperature evolution of Neutron powder diffraction confirms the absence of any structural changes in the range 300–6 K. Magnetic characterizations show antiferromagnetic ordering at room temperature and the co-existence of antiferromagnetic and ferromagnetic phases at low temperature. The magnetic structure derived from neutron powder diffraction is a G -type antiferromagnetic. The ordered magnetic moments at 6 K on the octahedral and tetrahedral sites are 3.15 (2) µ B /cation and 0.93 (4) µ B /cation, respectively oriented in the ac -plane. Graphical abstract Rietveld refined X-ray diffraction pattern at 300 K and magnetic structure obtained from Neutron diffraction at 6 K for Ca 2 Fe 0.875 Cr 0.125 GaO 5 fx1 Highlights • Crystal and magnetic structure of Ca 2 Fe 0.0875 Cr 0.125 GaO 5 was studied thoroughly. • Compound possesses orthorhombic Pnma space group. • ∼ 9% of Fe/Ga disorder between the Fe/Cr – octahedral and Ga –tetrahedral layers. • Magnetic structure is found to be G-type antiferromagnetic. [ABSTRACT FROM AUTHOR]

In the present contribution, structural and magnetic properties of Pulsed laser deposited (PLD) Co 2 FeGa (CFG) thin films have been studied as a function of substrate temperature. Structural investigation carried out by X-Ray Diffraction (XRD) measurement reveals mixed phase cubic structure of the films which changes from a nearly ordered to highly disordered phase with an increase in substrate temperature. Grazing Incidence X-Ray Diffraction (GIXRD) study shows the presence of disordered A2 phase similar to the bulk target. Grazing Incidence X-Ray Reflectivity (GIXR) measurement reveals the formation of bi-layer structure in the films with different density and thickness though the overall thickness remains same. Field Emission Scanning Electron Microscopy (FESEM) study shows the formation of a droplet-like morphology of the films. Extended X-ray Absorption Fine Structure (EXAFS) study serves a major role in complementing the XRD results and also shows a strong hybridization of Co with Ga maintaining the half metallicity. A novel approach in analyzing the EXAFS data additionally gives quantitative estimation of the different kinds of disorders present in the samples at the atomic level. In addition to this, magnetization result suggests that the films grown at lower substrate temperatures acts as proper ferromagnet following the well known spin wave theory with higher value of spontaneous magnetization in comparison to other samples. A lesser value of saturation magnetization in the films compared to bulk also supports the presence of antisite disorders. [ABSTRACT FROM AUTHOR]

Recently, equatorial secondary cosmic ray observatory has been established at Equatorial Geophysical Research Laboratory (EGRL), Tirunelveli, (Geographic Coordinates: 8.71°N, 77.76°E), to study secondary cosmic rays (SCR) produced due to the interaction of primary cosmic rays with the Earth’s atmosphere. EGRL is a regional center of Indian Institute of Geomagnetism (IIG), located near the equator in the Southern part of India. Two NaI(Tl) scintillation detectors are installed inside the temperature controlled environment. One detector is cylindrical in shape of size 7.62 cm × 7.62 cm and another one is rectangular cuboid of 10.16 cm × 10.16 cm × 40.64 cm size. Besides NaI(Tl) detectors, various other research facilities such as the Geomagnetic observatory, Medium Frequency Radar System, Digital Ionosonde, All-sky airglow imager, Atmospheric electricity laboratory to measure the near-Earth atmospheric electric fields are also available at EGRL. With the accessibility of multi- instrument facilities, the objective is set to understand the relationship between SCR and various atmospheric and ionospheric processes, during space weather and terrestrial events. For gamma-ray spectroscopy, it is important to test the performance of the NaI(Tl) scintillation detectors and to calibrate the gamma-ray spectrum in terms of energy. The present article describes the details of the experimental setup installed near the equator to study cosmic rays, along with the performance testing and calibration of the detectors under various conditions. A systematic shift in the gain is observed with varying temperature of the detector system. It is found that the detector’s response to the variations in the temperature is not just linear or non-linear type, but it depends on the history of the variation, indicating temperature hysteresis effects on NaI detector and PMT system. This signifies the importance of isothermal environment while studying SCR flux using NaI(Tl) detectors, especially for the experiments conducted during daytime such as solar eclipses etc. [ABSTRACT FROM AUTHOR]

Hole-doped La 2 CoO 4 compounds have been widely studied due to their multifaceted behavior such as charge ordering, spin ordering and spin blockade. Hole doping in La 2 CoO 4 causes appearance of the Co 3+ along with the Co 2+ , which makes it an interesting model system for study of the spin-state transitions. In hole-doped samples, the spin-states of the Co 3+ ions at large have been reported as the low or intermediate state. We report here a study on the Sr doping in La 2 CoO 4 . The Sr doping has been found to stabilize the crystal structure. By combining structural, electronic structure and electrical transport results, it is observed that the high-spin state is present in all the La 2− x Sr x CoO 4 (x = 0.5, 0.8, 0.9 and 1.0) samples. The high-spin state has been found to be concomitant with the delocalization of the e g electrons. In addition, in these materials, a colossal thermopower has been observed for first time in the cryogenic temperatures. [ABSTRACT FROM AUTHOR]

Understanding the microscopic origin of physical properties is fundamental to the study of glasses. In the present study, unique trends were observed in structural and dynamical properties in lead-borate [ x PbO:(1- x )B 2 O 3 ] glasses upon increasing the modifier. Properties driven by short-range structural changes like, glass transition temperature ( T g ) and elastic modulii exhibit a broad maxima around x = 0.3, in congruence with the average coordination number < r >. Using Raman spectroscopy, this behaviour is attributed to the gradual conversion of three-coordinate ( B 3 ) to four-coordinate ( B 4 ) boron species. However, dynamic properties like the Boson peak and fragility behave similar to the above structural properties except an anomalous dip at x = 0.3. The corresponding dynamic correlation length, therefore, exhibits a decrease except a peak at x = 0.3 with increasing x . The static correlation lengths estimated from the first sharp diffraction peak (FSDP), did not follow a linear trend with the dynamic correlation lengths, indicating a different spatial origin. The analysis of the Boson peak and FSDP suggests that while the Boson peak arises from intermediate-range ordering within the network units, the FSDP arises due to ordering of voids between such units. Moreover, the Boson peak maximum showed a linear decrease with increasing < r >, while the Boson peak position and fragility were found to vary linearly. These correlations emerge from the evolution of the network packing and connectivity with the addition of modifier and changing role of lead oxide as a glass former at higher concentrations. The anomalous variation in dynamical properties reflects the critical role of Pb 2+ in tuning the intermediate-range structure of the vitreous network. [ABSTRACT FROM AUTHOR]

UIr 2 was investigated using high pressure x-ray diffraction technique up to 55 GPa. The compound remains stable in its cubic structure (Space Group: Fd- 3 m ) up to 40 GPa. Above 40 GPa x-ray diffraction pattern indicates the emergence of a yet unidentified phase. The large structural stability of cubic MgCu 2 type structure, predicted empirically, is not exhibited in this compound. Zero pressure bulk modulus and its pressure derivative are found to be 284 GPa and 7.9 respectively. The high bulk modulus value obtained is indicative of itinerant nature of 5- f electrons which is also supported by Hill limit criteria. Electronic structure calculations indicate that uranium tetrahedral network is less rigid as compared to iridium tetrahedral network. Valley in density of states at Fermi level deepens with pressure vindicating observation of a more stable phase at high pressure. [ABSTRACT FROM AUTHOR]

Resonant photoemission spectroscopy has been used to investigate the character of Fe 3 d states in FeAl alloy. Fe 3 d states have two different character, first is of itinerant nature located very close to the Fermi level, and second, is of less itinerant (relatively localized character), located beyond ∼2 eV below the Fermi level. These distinct states are clearly distinguishable in the resonant photoemission data. Comparison between the results obtained from experiments and first principle based electronic structure calculations show that the origin of the itinerant character of the Fe 3 d states is due to the ordered B 2 structure, whereas the relatively less itinerant (localized) Fe 3 d states are from the disorders present in the sample. The exchange splitting of the Fe 3 s core level peak confirms the presence of local moment in this system. It is found that the itinerant electrons arise due to the hybridization between Fe 3 d and Al 3 s and 3 p states. Presence of hybridization is observed as a shift in the Al 2 p core-level spectra as well as in the X-ray near edge absorption spectra towards lower binding energy. Our photoemission results are thus explained by the co-existence of ordered and disordered phases in the system. [ABSTRACT FROM AUTHOR]

We have synthesized the Co 1.75 Fe 1.25 O 4 spinel ferrite by chemical reaction of Co and Fe nitrates at alkaline medium. We have annealed the as-prepared material up to 1100 °C to study the changes in lattice structure and magnetic properties. We have used synchrotron X-ray diffraction and Raman spectroscopy to identify the lattice structure. The material formed a composite spinel structure of Co rich phase (20–30%) and Fe rich phase (80–70%) for annealing temperature range 200–800 °C, and single phased spinel structure at 900 °C. At annealing temperature 1100 °C, the sample showed minor amount of hematite phase, in addition to two spinel phases. All the samples are ferrimagnetic in nature, but ferrimagnetic properties in mixed-phased samples are distinctly different from single phased sample. The analysis of the temperature and magnetic field dependence of magnetization data revealed a wide distribution of exchange interactions, anisotropy barriers, blocking of magnetic domains, and exchange bias for the samples having multi-phase components. On the other hand, single phased sample has shown the highest magnetization and the smallest coercivity with lowest distribution of magnetic exchange energy and anisotropy. [ABSTRACT FROM AUTHOR]

Earlier studies have successfully demonstrated that the GPS–TEC technique is a powerful method to study the propagation pattern of transient disturbances in the ionosphere. This technique has turned out to be sensitive enough to detect ionospheric signatures of ULF waves as well, particularly at high latitudes. It has already been reported earlier that during the recovery phase of the strong magnetic storm on Oct. 31, 2003, intense Pc5 geomagnetic activity was accompanied with distinct pulsations of the same periodicity in the TEC data from high-latitude GPS receiving stations. The present study reveals the identical features in geomagnetic and TEC data at low-latitude stations in the Indian sector as well. However, the presented observational results on TEC modulation by global Pc5 waves at low latitudes cannot be interpreted on the basis of the Alfven mode concept. The most promising mechanism that can explain the present observations is the plasma compression by fast magnetosonic mode. Theoretical order-of-magnitude estimates of the ratio between pulsation amplitudes in TEC and geomagnetic field based on the proposed mechanism is found to be about the same as the observed values. [ABSTRACT FROM AUTHOR]

Two welding consumables suitable for joining X80 linepipe steel are compared in terms of weld metal microstructures, hardness, impact toughness, and tensile properties. The chemical compositions of the consumables were similar, where one of the consumables had a rich wire chemistry containing higher C, Ni, Ti alloying additions compared to a lean one. Beads on plate welding were performed using the gas metal arc welding (GMAW) process set to achieve the same heat input of 0.66 kJ/mm. The results revealed that for both wires the weld metal microstructure was mainly consist of acicular ferrite. The consumable with richer chemistry (C, Ni and Ti) exhibited higher strength and hardness due to its finer final weld metal microstructure; however, Charpy impact tests results revealed the lean chemistry wire had higher toughness at low temperature. Since both weld metals exhibited similar acicular ferrite structures, the lower toughness of the richer chemistry weld was attributed to the presence of titanium inclusions which may provide crack initiation sites. [ABSTRACT FROM AUTHOR]

The spinel oxide Co 2.25 Fe 0.75 O 4 has been prepared by co-precipitation route. The as prepared material has been annealed at 800 °C under vacuum. Properties of the samples annealed under vacuum have been compared with the sample annealed in air. Synchrotron X-ray diffraction, Raman spectroscopy and X-ray absorption near edge structure spectroscopy have been used for structural phase characterization. The cubic spinel structure in air annealed sample has been splitted into Co and Fe rich phases. The Co rich spinel phase has transformed into Cobalt monoxide (CoO) after vacuum annealing. This has resulted an increase of Fe:Co ratio in the Fe rich spinel phase. Raman spectra indicated a transformation of the distribution of Co and Fe ions from normal spinel like structure for the sample annealed in air to mixed spinel structure for the samples annealed under vacuum. The existence tetravalent Fe 4+ ion has been confirmed in all the samples and it is new information for Co doped spinel ferrite system. All the samples exhibited ferrimagnetic behavior and exchange bias effect. The focus point is that vacuum annealing has been used as an effective route of material processing to control the structural phase and also, enhancement of magnetic properties in Co rich ferrite. [ABSTRACT FROM AUTHOR]

In the present work, important information on crystalline structure and band offset of InAs/Ge heterojunction epitaxially grown directly on Ge (111) substrate is presented. As revealed by high resolution x-ray diffraction (HRXRD) and Raman measurements the InAs nanostructures are highly crystalline and oriented with the substrate having predominantly zinc-blende (ZB) structure. The relaxation ratio of grown layer is of 95%. The lateral and vertical coherence lengths are estimated to be ∼65 nm and ∼14 nm, respectively, which closely match with atomic force microscopy results. As revealed from HRXRD experiments, two domains/sub-lattices of ZB InAs (111) structures having different stacking configurations were found to coexist. A band diagram is constructed for InO/InAs/Ge system. Valence band offset of 300 meV and conduction band offset of 20 meV for InAs/Ge have been determined. Hence, InAs/Ge (111) system can have potential application in low power devices. [ABSTRACT FROM AUTHOR]

The present work summarizes the effect of irradiation on the microstructure of Zr–1 wt.% Nb fuel cladding alloy using 5 MeV proton beam from a Variable Energy Cyclotron. The correlation between the damage energy deposition profile and the consequent microstructural modification has been obtained for different irradiation doses employing detailed line profile analysis of wide angle and Synchroton grazing incidence X-ray diffraction data. The inhomogeneous microstructure resulting from ion irradiation as a function of depth could be analyzed by these techniques. The size of the coherent domains was found to decrease drastically upon irradiation together with an increase in the microstrain values within these domains. A progressive decrease in the domain size, with a corresponding increase in the microstrain, was noticed upon increasing the dose of irradiation and along the depth of the irradiated samples. [ABSTRACT FROM AUTHOR]

High pressure structural stability studies were carried out on YGa 2 (AlB 2 type structure at NTP, space group P 6/ mmm ) up to a pressure of ~35 GPa using both laboratory based rotating anode and synchrotron X-ray sources. An isostructural transition with reduced c/a ratio, was observed at ~6 GPa and above ~17.5 GPa, the compound transformed to orthorhombic structure. Bulk modulus B 0 for the parent and high pressure phases were estimated using Birch–Murnaghan and modified Birch–Murnaghan equation of state. Electronic structure calculations based on projector augmented wave method confirms the experimentally observed two high pressure structural transitions. The calculations also reveal that the ‘Ga’ networks remains as two dimensional in the high pressure isostructural phase, whereas the orthorhombic phase involves three dimensional networks of ‘Ga’ atoms interconnected by strong covalent bonds. [ABSTRACT FROM AUTHOR]

Highlights: [•] The complete electrical design of 42GHz, 200kW gyrotron is presented. [•] Un-depressed collector and axial output system for RF power is selected. [•] Various commercially available design tools as well as in-house developed computer codes are used in the design process. [•] The experimental results of cold cavity analysis are also presented. [•] The design results show more than 200kW power with 40% interaction efficiency at 42GHz frequency. [Copyright &y& Elsevier]

Highlights: [•] Electrical design of single stage depressed collector for high power gyrotron tube. [•] Efficiency enhancement by collecting spent beam. [•] Optimization of geometry and magnetic field for optimized beam spread. [•] Optimization of cooling duct system for better thermal management. [Copyright &y& Elsevier]

Abstract: Titanosilicates with 3D-wormhole-like mesoporosity were used as support for hydroprocessing catalysts to increase the triglyceride (jatropha oil) deoxygenation and cracking activity of sulfided Ni-Mo and Co-Mo catalysts. Mesoporous titanosilicate supported Co-Mo catalyst showed improved performance in terms of higher yield of kerosene (jet-fuel) range hydrocarbons, 5-times more isomerized product and slightly improved activity than the traditional alumina supported catalyst. Higher acidity, better metal dispersion and favorable metal–support interactions could be attributed to the improved performance of the former. Among the mesoporous titanosilicate supported catalysts, sulfided Ni-Mo was more active than the Co-Mo catalyst (at lower temperature, 300°C, 4–8h−1) but with high selectivity for oligomeric products. But at higher temperatures the Co-Mo catalytic system showed comparable activities with increased yield of cracked products and the heavy range fraction. Response surface plots indicated that there was a combined effect of space velocity and temperature on the conversion at lower temperatures (300°C), which was less prominent at higher temperatures (>330°C). Kinetic model fitting results at lower temperatures (300–320°C) indicated direct conversion of triglycerides to deoxygenated products along with oligomeric and cracked products formation with no internal conversions between the products indicated. [Copyright &y& Elsevier]

Abstract: This paper presents the numerical simulation of a double-beam magnetron injection gun (DB-MIG) and beam-wave interaction for 60GHz, 500kW gyrotron. The beam-wave interaction calculations, power and frequency growth estimation are performed by using PIC code MAGIC. The maximum output power of 510kW at 41.5% efficiency, beam currents of 6A and 12A, electron beam velocity ratios of 1.41 and 1.25 and beam voltage of 69kV are estimated. To obtain the design parameters, the DB-MIG with maximum transverse velocity spread less than 5% is designed. The computer simulations are performed by using the commercially available code EGUN and the in-house developed code MIGANS. The simulated results of DB-MIG design obtained by using the EGUN code are also validated with another trajectory code TRAK, which are in good agreement. [Copyright &y& Elsevier]

Abstract: Long-term field trials using lignite fly ash (LFA) were carried out in rice crops during the period 1996–2000 at Mine I, Neyveli Lignite Corporation, Tamil Nadu. LFA, being alkaline and endowed with an excellent pozzolanic nature, silt loam texture, and plant nutrients, has the potential to improve the texture, fertility, and crop productivity of mine spoil. The rice crops were the first, third, fifth, and sixth crops in rotation. The other crops, such as green gram (second) and sun hemp (fourth), were grown as green manure. For experimental trials, LFA was applied at various dosages (0, 5, 10, 20, 50, 100, and 200t/ha), with and without press mud (10t/ha), before cultivation of the first crop. Repeat applications of LFA were made at the same dosages in treatments of up to 50t/ha (with and without press mud) before cultivation of the third and fifth crops. Press mud, a lightweight organic waste product from the sugar industry, was used as an organic amendment and source of plant nutrients. Also, a recommended dosage of chemical fertilizer, along with gypsum, humic acid, and biofertilizer as supplementing agents, was applied in all the treatments, including control. With one-time and repeat applications of LFA, from 5 to 20t/ha (with and without press mud), the crop yield (grain and straw) increased significantly (p<0.05), in the range from 3.0 to 42.0% over the corresponding control. The maximum yield was obtained with repeat applications of 20t/ha of LFA with press mud in the third crop. The press mud enhanced the yield in the range of 1.5–10.2% with various dosages of LFA. The optimum dosage of LFA was 20t/ha for both one-time and repeat applications. Repeat applications of LFA at lower dosages of up to 20t/ha were more effective in increasing the yield than the corresponding one-time applications of up to 20t/ha and repeat applications at 50t/ha. One-time and repeat applications of LFA of up to 20t/ha (with and without press mud), apart from increasing the yield, evinced improvement in the texture and fertility of mine spoil and the nutrient content of crop produce. Furthermore, some increase in the content of trace and heavy metals and the level of γ-emitters in the mine spoil and crop produce was observed, but well within the permissible limits. The residual effect of LFA on succeeding crops was also encouraging in terms of eco-friendliness. Beyond 20t/ha of LFA, the crop yield decreased significantly (p<0.05), as a result of the formation of hardpan in the mine spoil and possibly the higher concentration of soluble salts in the LFA. However, the adverse effects of soluble salts were annulled progressively during the cultivation of succeeding crops. A plausible mechanism for the improved fertility of mine spoil and the carryover or uptake of toxic trace and heavy metals and γ-emitters in mine spoil and crop produce is also discussed. [Copyright &y& Elsevier]

Abstract: This paper discusses observations of dynamic magnetic field variations on auroral field lines at mid and high altitudes, utilizing a conjunction of POLAR and INTERBALL-Auroral spacecraft in the dusk magnetosphere on January 11, 1997. Both spacecraft indicate the presence of periodic magnetic variations in the Pc5 frequency range in the field-aligned current region 1. The satellites are believed to be closely on the same field line or within a flux tube (radius 130km of its projection in the ionosphere). The polarization analysis shows an interesting event: a rotation of the main polarization axis by about 90° between POLAR and INTERBALL. When the two spacecraft are very close to a common field line, the difference between their observed magnetic fields might arise from a rotation of the field between the two altitudes. We cannot exclude different polarization properties arising from different horizontal positions (although small) of both satellite with respect to local plasma boundary. Frequency analysis of both solar wind density (WIND) and INTERBALL magnetic field showed that the solar wind pressure variation contains the same spectrum (2.4–4.4mHz). It appears that the solar wind pressure variations are sufficient for a parametric mechanism of excitation of compressional disturbances propagating along the magnetopause and within the magnetospheric cavity. [Copyright &y& Elsevier]

Reports several issued related to medicine in Great Britain. Objectives of oncology; Assessment on the hygienic standards in the National Health Service; Interrelation between coronary heart disease and menopause.

The structural and light emission properties of calcium tungstate (CaWO 4) nanoparticles containing Eu3+ and Dy3+ are studied. CaWO 4 nanoparticles were prepared by chemical routes followed by drying at 80°C, doping with 1, 3, 5, 7 and 10 mol% of Eu 2 O 3 and/or Dy 2 O 3 and final annealing at 800oC. The samples were characterized by field emission-scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDS), synchrotron X-ray diffraction (XRD), Raman and photoluminescence (PL) spectroscopy. FE-SEM studies show that CaWO 4 sample dried at 80°C contains spherical particles of diameter ∼5 μm, and upon annealing at 800°C, dense and irregular shaped structures are formed. EDS mapping found a uniform distribution of Eu and Dy ions and only a small segregation in the CaWO 4 matrix is observed. XRD studies revealed the co-existence of the tetragonal CaWO 4 and cubic Dy 2 O 3 and/or Eu 2 O 3 phases in the doped samples and rule out the replacement of Ca2+ by rare-earth ions. The structural parameters: crystallite size, lattice strain, unit cell dimensions, atomic position coordinates, bond-lengths, bond-angles and cation-oxygen coordination numbers were determined. The short-range structure of CaWO 4 consists of interconnected CaO 8 and WO 4 units. All the W–O bonds in WO 4 units have the same length whereas two types of Ca–O bond-lengths exist in CaO 8 units. The undoped CaWO 4 sample annealed at 800°C, has the smallest Ca–O bond-lengths and unit cell dimensions due to the compressive macrostrain induced by heat-treatment. On incorporating Eu3+ and Dy3+, the W–O and Ca–O bond-lengths increase slightly. Raman spectra of all the samples are similar and show W–O vibrational modes. PL studies found that the undoped CaWO 4 , Eu and Dy-doped CaWO 4 samples emit blue, red and yellow light respectively. The co-doped sample: 2 mol% Eu 2 O 3 –5 mol% Dy 2 O 3 –CaWO 4 was closest to the ideal white light emission properties. • Structure-property correlations in Eu 2 O 3 /Dy 2 O 3 and CaWO 4 composite samples. • Eu and Dy ions expand CaWO 4 lattice. • 3-Mol% Eu 2 O 3 gives maximum luminescence in CaWO 4. • Luminescence intensity decreases with increase in Dy 2 O 3 from 1 to 10 mol%. • Eu and Dy co-doping in CaWO 4 produces white light emission. [ABSTRACT FROM AUTHOR]

UZr 2 has been synthesized using the arc-melting technique. At ambient the compound is found to crystallize in a modified C32 , AlB 2 type structure, called δ-structure and it remains stable up to 20 GPa. However, an anomalous decrease of c/a ratio has been observed in different pressure intervals at ambient temperature. At elevated temperature c/a ratio, shows a marginal increase with pressure. The bulk modulus and its pressure derivative at ambient temperature are found to be 108.3 GPa and 5.0, respectively. High-pressure and high-temperature studies reveal a softening in the material at higher temperatures. The thermal expansion coefficients are found to decrease from 4.6 × 10−5 K−1 at 1.2 GPa to 2.7 × 10−5 K−1 at 6.6 GPa in the temperature range 300 K–473 K. • Bulk modulus of UZr 2 is 108.3 GPa at ambient & 101.6 GPa at 473 K indicating softening at high temperature. • Anomaly in rate of c/a @ P is due to strengthening of U - Zr covalent bond along the ' a ' axis at higher pressures. • c/a ratio is found to increase marginally in HP-HT experiments as compared to near-constant c/a in HP experiments. • A usual decrease in the thermal expansion coefficient, is observed in the temperature range 300 K–473 K. [ABSTRACT FROM AUTHOR]

Electron-irradiation induced changes in structural and, magnetic properties of Co 57.6 Fe 14.4 Si 4.8 B 19.2 Nb 4 , Fe 72 Si 4.8 B 19.2 Nb 4 and, Co 72 Si 4.8 B 19.2 Nb 4 metallic glasses were studied using magnetic hysteresis and, synchrotron X-ray diffraction measurements. Results reveal composition dependent changes of magnetic properties in electron irradiated metallic glasses. A low electron irradiation dose (15 kGy) enhances saturation magnetization (up to 62%) in Fe-based alloy (Fe 72 Si 4.8 B 19.2 Nb 4 ). Synchrotron XRD measurements reveal that electron irradiation transforms the amorphous matrix to a more ordered phase, accountable for changes in magnetic properties. [ABSTRACT FROM AUTHOR]