Miracle-dz/UniFAR-FTUs huggingface dataset:
New Permanent Magnet Materials

After an introduction to what is required of a high-performance permanent magnet material, a brief description is given of the Concerted European Action on Magnets, a unique cooperative research programme which involves more than fifty participants (a third of them industrial) from nine countries in the EEC. There follows an account of recent progress in understanding the intrinsic magnetic properties of Nd2Fe14B, and other isostructural compounds and solid solutions. Finally some directions in the search for new iron-rich phases with a high Curie point and uniaxial anisotropy are indicated.
Photo-assisted control of gold and silver nanostructures on silicon and its SERRS effect

A facile approach to control the growth of gold nanostructures on n-type silicon by galvanic displacement was demonstrated previously. It was observed that in the presence of light and red laser, at initial stages, gold nano-needles were formed, which then grew perpendicular to the substrate with time. However, the growth process has not yet been understood completely. Here, we have attempted to understand the galvanic displacement phenomena in the presence and absence of light by characterizing the growth process using transmission electron microscopy, atomic force microscopy and x-ray diffraction. Furthermore, we also evaluated the effect of laser on the deposition of silver on silicon wherein the use of green laser resulted in the formation of dendrites, whereas spherical nanoparticles were formed in dark. To further evaluate the benefits of the metal–semiconductor hybrid structure, we also evaluated the surface enhanced resonance Raman spectroscopy (SERRS) of the hybrid substrates and give evidence of the importance of the semiconductor substrate/metal–semiconductor interface in enhancing the SERRS activity.
Non-local continuity equations and binary Darboux transformation of noncommutative (anti) self-dual Yang–Mills equations

We present an infinite number of non-local continuity equations of noncommutative (anti) self-dual Yang–Mills (nc-(A)SDYM) equations using the induction method of Brézin et al (1979 Phys. Lett. B 82 442) and relate it to the Lax pair and the parametric Bäcklund transformation of the system. From the Lax pair, we derive a binary Darboux transformation to generate solutions of the nc-(A)SDYM equations.
Moistening Processes before the Convective Initiation of Madden–Julian Oscillation Events during the CINDY2011/DYNAMO Period

AbstractConvective initiation processes in the Madden–Julian oscillation (MJO) events that occurred during the Cooperative Indian Ocean Experiment on Intraseasonal Variability in the Year 2011 (CINDY2011)/Dynamics of the Madden–Julian Oscillation (DYNAMO) intensive observation period (IOP) were investigated. Two episodes that were initiated in mid-October (MJO1) and mid-November (MJO2) 2011 were analyzed using European Centre for Medium-Range Weather Forecasts (ECMWF) reanalysis and satellite data. Moisture budgets in the equatorial Indian Ocean (IO) domain (10°S–10°N, 60°–90°E) were analyzed in detail by separating each variable into basic-state (>80 day), intraseasonal (20–80 day), and high-frequency (<20 day) variations. The quality of the ECMWF reanalysis was also evaluated against the sounding data collected during the field campaign.In both MJO events, the increase in precipitable water started 8–9 days prior to the convective initiation. Moisture advection decomposition revealed that advection of b.
Front d'onde des représentations des groupes classiques p-adiques

<p class="summaryheading"><span class="summaryheading">Résumé. :</span></p><p>Dans cet article, on rappelle la définition algébrique du front d'onde d'une représentation lisse d'un groupe <i>p</i>-adique, donnée par Kawanaka. On en donne quelques propriétés; en particulier pour les groupes classiques <i>p</i>-adiques, on montre que ce front d'onde ne contient que des orbites unipotentes spéciales. On termine en montrant que si ce front d'onde est induit, dans certains cas, cela entraine que la représentation est elle aussi induite. </p>
Interdiffusion in epitaxial Co/Pt multilayers

Interdiffusion kinetics were measured using x-ray diffraction methods in epitaxial (001) and (111) Co/Pt multilayers in which the chemical modulation wavelength was in the range 2.5–4.0 nm. Multilayers were prepared by e-beam evaporation and were subsequently annealed in vacuum at temperatures between 275 and 375 °C. The activation enthalpy of the interdiffusion process in this temperature range was estimated using a novel approach for scaling nonlinear diffusion data. Activation enthalpies for interdiffusion in (001) and (111) multilayers were determined to be 1.1±0.2 and 0.8±0.2 eV, respectively. The low values obtained for the activation enthalpies may result from coherency strains or “short-circuit’’ diffusion in the faulted, epitaxial multilayers.
On the subgroup structure of exceptional groups of Lie type

We study finite subgroups of exceptional groups of Lie type, in particular maximal subgroups. Reduction theorems allow us to concentrate on almost simple subgroups, the main case being those with socle X(q) of Lie type in the natural characteristic. Our approach is to show that for sufficiently large q (usually q > 9 suffices), X(q) is contained in a subgroup of positive dimension in the corresponding exceptional algebraic group, stabilizing the same subspaces of the Lie algebra. Applications are given to the study of maximal subgroups of finite exceptional groups. For example, we show that all maximal subgroups of sufficiently large order arise as fixed point groups of maximal closed subgroups of positive dimension.
Comparison of fluid and particle-in-cell simulations on atmospheric pressure helium microdischarges

Microdischarges at atmospheric pressure were studied by two computational methods. The first method is a typical one-dimensional fluid model in which the electron velocity distribution function is assumed to be Maxwellian and the energy equation is solved to determine the spatial profile of the electron temperature. The second method is a particle-in-cell (PIC) model with Monte-Carlo collisions (MCC). We compared the time-averaged density, electric field and power consumption profiles of helium microdischarges driven at 13.56 MHz and 2.45 GHz obtained with the two models. The agreement between the two models depends on the driving frequency. The kinetic information obtained from the PIC-MCC model indicates that the improved agreement at higher frequency is due to the evolution of the electron energy distribution function from a three-temperature distribution at 13.56 MHz to a close-to-Maxwellian distribution at 2.45 GHz.
Acceleration of particles in the upper ionosphere and the magnetosphere due to decay interactions of whistlers, part 1

A numerical analysis of the three-wave decay interaction of oblique whistler mode waves with different types of ion waves is presented. It is shown that at altitudes h < 2000 km the most effective mechanism is the decay interaction of whistlers with quasielectrostatic ion-cyclotron waves (the increment is Γ ~ 25s−1 for an initial whistler pump wave amplitude of 10 = 10 mVm-1) as well as with Alfven waves and ion-ion hybrid waves (Γ ~ 10s−1 for the same pump amplitude 10). When taking into account the media inhomogeneity and the decay wave stabilization due to pump wave amplitude depletion, the magnitudes of excited ion waves are found to be E3 ~ 50-120μV/(mHz½) for 10 = 10 mVm-1. At such amplitudes parametrically excited ion waves can provide transverse ion acceleration with a rate of 0.5eVs−1 and longitudinal electron acceleration up to 5eV at a distance of the order of 2000 km, the flux reaching 3 × 107 el/(cm2s sr eV).
A note on optimal allocations for the second elementary symmetric function with applications for optimal reliability design

This article considers the problem of determining the optimal size allocation and optimal number of experimental conditions for a second elementary symmetric function with different coefficients. Analytical solutions for several practical applications are derived and the general formulation is used to elucidate the foundation between different parametric models found in recent studies. A geometrical interpretation of the structure of some theoretical results is also provided. This approach renders some complex problems more tractable than what numerical search algorithms would allow. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2012
THE TURBULENCE STRUCTURE OF A REATTACHING AXISYMMETRIC COMPRESSIBLE FREE SHEAR LAYER

The reattachment of a supersonic, axisymmetric shear layer downstream of a blunt-based afterbody is studied. Of primary interest are the effects of the “extra” strain rates, such as bulk compression, concave streamline curvature, and lateral streamline convergence associated with shear layer reattachment on the structure of the turbulence field. Experimental turbulence data obtained throughout the reattachment region with a two-component laser Doppler velocimeter are presented. In general, the axisymmetric compliant boundary reattachment process is shown to be different in character compared to the planar solid wall case. Most notably, significant reductions in the Reynolds stresses occur through the reattachment region due to the dominating effect of lateral streamline convergence as the flow approaches the axis. Similar to the planar solid wall case, however, a reduction in the mean turbulent transport toward the axis in the reattachment region was found, which suggests a radial containment of the large.
Ligament creep behavior can be predicted from stress relaxation by incorporating fiber recruitment

Structural modeling and morphological crimp analysis were used to investigate if collagen fiber recruitment could account for our previous finding, that ligament creep behavior cannot be predicted using inverse stress relaxation behavior directly. Ligament creep behavior was accurately predicted using our simple nonlinear structural model that incorporated collagen fiber creep and collagen fiber recruitment. Collagen fiber creep was modeled using the inverse stress relaxation function and estimated fiber modulus. Collagen fiber recruitment was modeled with a linear variation in crimp over an idealized rectangular ligament cross section. Concomitantly, significant differences in collagen crimp patterns were observed as a result of creep testing; however; no significant changes were observed as a result of relaxation testing. This morphological evidence supported the model assumptions that fiber recruitment occurs during creep and that stress relaxation behavior results from the viscoelastic response of an .
Modelling the number of customers as a birth and death process

Birth and death may be a better model than Brownian motion for many physical processes, which real options models will increasingly need to deal with. In this paper, we value a perpetual American call option, which gives the monopoly right to invest in a market in which the number of active customers (and hence the sales rate) follows a birth and death process. The problem contains a singular point, and we develop a mixed analytic/numeric method for handling this singular point, based on the method of Frobenius. The method may be useful for other cases of singular points. The birth and death model gives lower option values than the geometric Brownian motion model, except at very low volatilities, so that if a firm incorrectly assumes a geometric Brownian motion process in place of a birth and death process, it will invest too seldom and too late.
Hot electrons in low-dimensional structures

The properties of hot electrons in systems where electrons and phonons experience quantum confinement are reviewed. The modifications to the behaviour of electrons and phonons brought about by confinement are described, particularly with reference to the principal scattering mechanism. The latter include the interaction with longitudinal optical phonons and plasmons, along with carrier-carrier effects. Some conflict in the literature concerning Fuchs-Kliewer polaritons is discussed. Low-temperature interactions with acoustic phonons are described. A central topic is that of energy relaxation, and the experimental and theoretical data relating to this form a large part of the review. Energy relaxation mechanisms in the femtosecond to nanosecond regimes, including intersubband and well-capture processes, are eventually summarized. An equally large section deals with hot-electron transport; in which negative differential resistance and other instabilities associated with parallel transport are discussed before turning to ballistic transport and impact ionization.
Solving inverse two-point boundary value problems using collage coding

The method of collage coding, with its roots in fractal imaging, is the central tool in a recently established rigorous framework for solving inverse initial value problems for ordinary differential equations (Kunze and Vrscay 1999 Inverse Problems 15 745–70). We extend these ideas to solve the following inverse problem: given a function u(x) on [A, B] (which may be the interpolation of data points), determine a two-point boundary value problem on [A, B] which admits u(x) as a solution as closely as desired. The solution of such inverse problems may be useful in parameter estimation or determination of potential functional forms of the underlying differential equation. We discuss ways to improve results, including the development of a partitioning scheme. Several examples are considered.
Algebraic independence of reciprocal sums of powers of certain Fibonacci-type numbers

: The Fibonacci-type numbers in the title look like R n = g 1 γ n 1 + g 2 γ n 2 and S n = h 1 γ n 1 + h 2 γ n 2 for any n ∈ Z , where the g ’s, h ’s, and γ ’s are given algebraic numbers satisfying certain natural conditions. For ﬁxed k ∈ Z > 0 , and for ﬁxed non-zero periodic sequences ( a h ) , ( b h ) , ( c h ) of algebraic numbers, the algebraic independence of the series is studied. Here the main tool is Mahler’s method which reduces the investigation of the algebraic independence of numbers (over Q ) to that of functions (over the rational function ﬁeld) if they satisfy certain types of functional equations.
Structure of boroaluminosilicate glasses: Impact of [Al2O3]/[SiO2] ratio on the structural role of sodium

Q. J. Zheng,1,2 R. E. Youngman,2,* C. L. Hogue,2 J. C. Mauro,2 M. Potuzak,2 M. M. Smedskjaer,2 and Y. Z. Yue1,3 1Section of Chemistry, Aalborg University, DK-9000 Aalborg, Denmark 2Science & Technology Division, Corning Incorporated, Corning, New York 14831, USA 3Shandong Key Laboratory of Glass and Ceramics, Shandong Polytechnic University, 250353 Jinan, China (Received 28 March 2012; published 22 August 2012)
Physical Characteristics of Near-Earth Asteroids from Thermal Infrared Spectrophotometry☆

Thermal infrared spectrophotometric observations of the near-Earth asteroids 433 Eros, 1980 Tezcatlipoca, and 3671 Dionysus are presented and their implications for the physical characteristics of the objects discussed. Sizes and albedos are derived on the basis of published thermal models and comparison of the infrared data with optical observations. The results for 433 Eros are in very good agreement with radar and other earlier findings and demonstrate the accuracy achievable with one of the thermal models used. The new data, together with earlier results from the literature, suggest the surface thermal inertia of 433 Eros is no larger than three times that of the Moon. The derived effective diameter and optical albedo of 1980 Tezcatlipoca (around lightcurve maximum) are D=6.7±1.0 km and pV=0.15±0.05, and for 3671 Dionysus D=1.0±0.2 km and pV=0.40±0.15. These diameters are significantly different from previous estimates. The thermal continua of Tezcatlipoca and Dionysus are indicative of high surface thermal inertias. A near-infrared spectrum of Dionysus, coupled with the high albedo, suggests an M or E classification. Such taxonomic types are relatively rare amongst near-Earth asteroids.
HII Regions of NGC 628 and M101 as seen with SpIOMM

Abstract With SpIOMM, we obtained numerous spectra in the visible range covering simultaneously several emission lines of bright Hii regions in the spiral galaxies NGC 628 and M101. We measured the size and luminosity of the Hii regions as well as the gas metallicity, temperature, and density. We estimated the age and star forming rate of the young stellar populations associated with the Hii regions. We looked for gradients along the galaxy radius and search for relations with the galactic arm positions. This is a first step in a project, based on a detailed study of stellar populations, to rebuild the history of spiral galaxies and to identify the mechanisms responsible for their evolution.
SEM and X-Ray Diffraction Studies on Microstructures in Cu-26.04%Zn-4.01%Al Alloy

Due to fact that Cu-based alloys are very sensitive to the thermal treatments, in scanning electron microscopy and X-ray di raction observations, according to the di erent quenching techniques Cu 26.04%Zn 4.01%Al alloys can display di erent product phases such as martensite and precipitation. Rapidly cooling sample was formed as M18R structure from the ordered DO3 phase and in the monoclinic case, β = 89.1 ◦ determined for sample. It was seen that a α-precipitation (fcc) phase in the matrix is slowly cooling.
Iterative multi-resolution retrieval of non-measurable equivalent currents for the imaging of dielectric objects

In this paper, an iterative multi-resolution method for the reconstruction of the unmeasured components of the equivalent current density is proposed in order to improve the retrieval of the dielectric properties of an unknown scenario probed by interrogating electromagnetic waves. The mathematical formulation, concerned with lossless as well as lossy dielectric scatterers, is provided and the theory is supported by a set of representative examples dealing with synthetic as well as experimental scattering data.
UBV PHOTOMETRY OF ECLIPSING BINARIES WITH VISUAL COMPANIONS.

Nineteen eclipsing binaries with visual companions were observed photoelectrically. Comparison stars were chosen, one for each eclipsing binary and its companion, and tied in to the UBV system. Then differential UBV magnitudes, relative to these comparison stars, were obtained for the binary, companion, and/or binary-plus-companion. Key words: eclipsing binaries - UBV photometry - visual binaries
A spectrometer for pulsed and continuous photon radiation

A spectrometer consisting of thermoluminescence detectors (TLDs) placed in a stack of different absorbers is used to determine the absolute fluence and energy distribution (spectrum) in both, continuous and pulsed photon radiation fields. Spectra can reliably be determined in the energy range between a few keV and several MeV: if the measurement is taken in vacuum, the upper energy limit rises to about 100 MeV. The maximal deviation of the mean energy and absolute fluence (and hence the absolute dose) from the correct values is about 10% and 20%, respectively.
Quasilinear theory of anisotropy‐beta relations for proton cyclotron and parallel firehose instabilities

[1] The solar wind and the Earth's magnetosheath frequently possess proton temperature anisotropies that violate the predictions of adiabatic fluid theory. In the literature, various threshold conditions expressed as inverse correlations between the proton anisotropy, T⊥/T∥, and parallel beta, β∥, have been constructed on the basis of linear stability analysis for anisotropy-driven instabilities, hybrid simulations, or by simply fitting the observations. ForT⊥/T∥ > 1, proton cyclotron and mirror instabilities are operative, while for T∥ > T⊥, parallel and oblique firehose instabilities can be taken into account in the construction of the inverse correlation. In the present paper, quasilinear kinetic theory of parallel proton cyclotron and firehose instabilities are employed to self-consistently construct theT⊥/T∥ vs β∥threshold conditions. In principle, such an approach eliminates the necessity for empirical models of inverse correlations, since inverse correlations should naturally emerge as the time-asymptotic states of quasilinear processes. It is found that the self-consistent threshold conditions constructed on the basis of quasilinear formalism compare reasonably well with available models, thus confirming that quasilinear method is a reasonable approach.
Super‐resolution microscopy by movable thin‐films with embedded microspheres: Resolution analysis

Microsphere‐assisted imaging has emerged as an extraordinary simple technique of obtaining optical super‐resolution. This work addresses two central problems in developing this technology: i) methodology of the resolution measurements and ii) limited field‐of‐view provided by each sphere. It is suggested that a standard method of resolution analysis in far‐field microscopy based on convolution with the point‐spread function can be extended into the super‐resolution area. This allows developing a unified approach to resolution measurements, which can be used for comparing results obtained by different techniques. To develop the surface scanning functionality, the high‐index (n ∼ 2) barium titanate glass microspheres were embedded in polydimethylsiloxane (PDMS) thin‐films. It is shown that such films adhere to the surface of nanoplasmonic structures so that the tips of embedded spheres experience the objects’ optical near‐fields. Based on rigorous criteria, the resolution ∼λ/6‐λ/7 (where λ is the illumination wavelength) is demonstrated for arrays of Au dimers and bowties. Such films can be translated along the surface of investigated samples after liquid lubrication. It is shown that just after lubrication the resolution is diffraction limited, however the super‐resolution gradually recovers as the lubricant evaporates.
Next generation 8xx nm laser bars and single emitters

Semiconductor lasers with emission in the range 790 - 880 nm are in use for a variety of application resulting in different laser designs to fulfill requirements in output power, operation temperature and lifetimes. The output power is limited by self heating and catastrophic optical mirror damage at the laser facet (COMD). Now we present data on bars fabricated with our new facet technology, which enables us to double the maximum facet load. We present q-cw laser bar with 80% fill factor with increased power level to 350W in long term operation at 200μs and 100Hz. The COMD limit of the bar is as high as 680W. Using Quantel's optimized packaging stacks with 11 bars of 5mm widths are tested at up to 120A resulting over 66% power conversion efficiency at 1600W output power. Laser bars for continuous wave operation like 50% fill factor bars had an COMD limit of approx. 250W with conventional facet technology, the value is equivalent to 10W per 200μm emitter (conditions: 200μs). The new facet technology pushes the facet stability to 24W/emitter. The new process and an improved design enable us to shift continuous wave operation at 808nm from 100W to 150W/bar with lifetimes of several thousand hours at 30°C using DILAS mounting technology. Higher power is possible depending on lifetime requirements. The power conversion efficiency of the improved devices is as high as 62% at 200W cw. The next limitation of 8xxnm lasers is high temperature operation: Values of 60-80°C are common for consumer applications of single emitters. Therefore Osram developed a new epitaxial design which reduced the generation of bulk defects. The corresponding Osram single emitters operate at junction temperatures up to 95°C, a value which corresponds to 80°C heat sink temperature for lasers soldered on C-mount or 65°C case temperature for lasers mounted in TO can. Current densities of the single emitter broad area lasers are as high as 1.4kA/cm2 at 850nm emission wavelength.