Energy Technology Data Exchange (ETDEWEB)

The theme of the conference was recent developments in airborne remote sensing and their applications. The proceedings contain the papers presented at 14 general sessions and 13 interactive sessions covering airborne platforms, sensor systems, airborne/spaceborne synergy, atmospheric and oceanic measurements, land cover/land use, emergency response and reconnaissance, data handling, forestry, agriculture, water resources, geospatial reference, system calibration, environmental monitoring and planning, and information product advancements. Two papers are abstracted separately.

KoreaScience (Korea)

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International Nuclear Information System (INIS)

Measurements of the magnetic susceptibility betweeen 0.03 and 300 K and of the magnetization between 0.05 and 10 K for magnetic fields up to 60kOe have been used to investigate effects from the interaction between the conduction electrons and local magnetic moments in (Lasub(1-x)Cesub(x))B_6 alloys (0.0007<=x<=0.10). For Ce concentrations x<0.006 the data show Kondo-type single impurity behaviour at low temperatures with a transition from a magnetic to a non-magnetic regime of the Ce ions. In the magnetic regime the impurity susceptibility follows a Curie-Weiss law, and in the non-magnetic regime it varies with T"2. An external magnetic field gradually restores the free-ion behaviour of the Ce impurities. For more concentrated alloys interactions ...

Energy Technology Data Exchange (ETDEWEB)

The thermal decrease of the order parameter can empirically be described by a single T{sup {epsilon}} power law with an exponent {epsilon} which depends on the dimensionality of the magnetic interactions and on whether the spin quantum number is integral or half-integral. We present experimental examples in which the order parameter shows a crossover between different T{sup {epsilon}} power laws as a function of temperature. This indicates that the magnetic interactions can change their dimensionality as a function of temperature. (orig.)

UK PubMed Central (United Kingdom)

Magnetotactic bacteria contain chains of magnetically interacting crystals (magnetosome crystals), which they use for navigation (magnetotaxis). To improve magnetotaxis efficiency, the magnetosome crystals...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Annual averages of the diurnal variation in cosmic ray intensity from neutron monitors in Deep River and Oulu and underground muon telescopes in Bolivia and at Embudo and Socorro, New Mexico, have been determined as a function of the sense of the interplantary magnetic field for the years 1965--1975. These data point to a cosmic ray density gradient, perpendicular to the ecliptic plane, pointing southward prior to 1969 and changing to a northward pointing gradient after the reversal of the sun's polar magnetic field in 1969--1971. This result supports numerical calculations for the prereversal and postreversal field configurations at intermediate and high cosmic ray rigidities.

British Library Electronic Table of Contents (United Kingdom)

We describe a class of organic molecular magnets based on zwitterionic molecules (betaine derivatives) possessing donor, p bridge, and acceptor groups. Using extensive electronic structure calculations we show the electronic ground-state in these systems is magnetic. In addition, we show that the large energy differences computed for the various magnetic states indicate a high Neel temperature. The quantum mechanical nature of the magnetic properties originates from the conjugated p bridge (only p electrons) in cooperation with the molecular donor-acceptor character. The exchange interactions between electron spin are strong, local, and independent on the length of the p bridge.

Energy Technology Data Exchange (ETDEWEB)

In vitro cytocompatibility and cellular interactions of lauric acid and dextran-coated magnetite nanoparticles were evaluated with two different cell lines (mouse fibroblast and human cervical carcinoma). Lauric acid-coated magnetite nanoparticles were less cytocompatible than dextran-coated magnetite nanoparticles and cellular uptake of lauric acid-coated magnetic nanoparticles was more than that of dextran-coated magnetite nanoparticles. Lesser cytocompatibility and higher uptake of lauric acid-coated magnetite nanoparticles as compared to dextran-coated magnetic nanoparticles may be due to different cellular interactions by coating material. Thus, coating plays an important role in modulation of biocompatibility and cellular interaction of magnetic nanoparticles.

Energy Technology Data Exchange (ETDEWEB)

We present a formulation of ab initio electronic structure calculations in a finite magnetic field, which retains the simplicity and efficiency of techniques widely used in first principles molecular dynamics simulations, based on plane-wave basis sets and Fourier transforms. In addition we discuss results obtained with this method for the energy spectrum of interacting electrons in quantum wells, and for the electronic properties of dense fluid deuterium in a uniform magnetic field.

Energy Technology Data Exchange (ETDEWEB)

The nuclear interaction probability of light charged particles in BaF[sub 2] crystals has been studied as a function of the incident particle energy. Light charged particles were identified in charge and mass by measuring their magnetic rigidity and their time-of-flight. The percentage of particles undergoing nuclear interactions has been measured for particles of charge from Z=1 to Z=6 and the experimental data are compared with the results of a model calculation. (orig.)

International Nuclear Information System (INIS)

We compare experimental data for temperature dependence of the magnetic order parameter and the magnetic excitations (spin waves) in materials with a quenched orbital moment and a well-defined spin quantum number. It is observed that the thermal decrease of the two quantities proceeds according to the same analytical function of the type y(T)=1-cT"#epsilon# with an identical exponent #epsilon#. This power function applies not only asymptotically for T->0 but holds over a wide temperature range. The exponent #epsilon# is universal, i.e. independent of spin order type and lattice symmetry and depends only on the dimensionality of the relevant interactions and on whether the spin quantum number is integer or half-integer. The different T"#epsilon# functions are identified as representations of stable universality classes. The fact that order parameter and magnetic excitations follow the same T"#epsilon# ...

CERN Document Server

We report on the magnetic hyperthermia properties of chemically synthesized ferromagnetic 11 and 16 nm Fe(0) nanoparticles of cubic shape displaying the saturation magnetization of bulk iron. The specific absorption rate measured on 16 nm nanocubes is 1690+-160 W/g at 300 kHz and 66 mT. This corresponds to specific losses-per-cycle of 5.6 mJ/g, largely exceeding the ones reported in other systems. A way to quantify the degree of optimization of any system with respect to hyperthermia applications is proposed. Applied here, this method shows that our nanoparticles are not fully optimized, probably due to the strong influence of magnetic interactions on their magnetic response. Once protected from oxidation and further optimized, such nano-objects could constitute efficient magnetic cores for biomedical applications requiring very large heating power.

DEFF Research Database (Denmark)

This article explores how action research, design based research and interaction design can be combined and used in the development of educational robotic tools. Our case study is the development of Number Blocks and it combines physical interaction, learning, and immediate feedback. Number Blocks supports the children's understanding of place value in the sense that it allows them to experiment with creating large numbers. The development was done in collaboration with a class of 7-8 year old children and their mathematics teacher. The article argues that elements from different research methods allowed a structured approach to projects that combines educational research and innovation of new learning technologies. Key elements of this approach is acknowledging the users input, developing a theoretical pre-analysis and using an iterative approach.

Energy Technology Data Exchange (ETDEWEB)

The existence of multipole components in the dipole and quadrupole magnets is one of the factors limiting the beam stability in the RHIC operations. So, a realistic non-linear model is crucial for understanding the beam behavior and to achieve the ultimate performance in RHIC. A procedure is developed to build a non-linear model using the available multipole component data obtained from measurements of RHIC magnets. We first discuss the measurements performed at different stages of manufacturing of the magnets in relation to their current state in RHIC. We then describe the procedure to implement these measurement data into tracking models, including the implementation of the multipole feed down effect due to the beam orbit offset from the magnet center. Finally, the field quality analysis in the RHIC interaction regions (IR) is presented.

UK PubMed Central (United Kingdom)

Natural abundance 13C solid-state nuclear magnetic resonance spectroscopy was used to investigate the effect of the incorporation of cholesterol on the dynamics of dimyristoylphosphatidylcholine (DMPC)...Full Text Available

International Nuclear Information System (INIS)

The magnetic properties of as-grown Ga1-xMnxAs have been investigated by the systematic temperature and magnetic field dependent soft x-ray magnetic circular dichroism (XMCD) measurements in the Mn L2,3 absorption edge region. The XMCD intensity at high temperatures obeys the Curie-Weiss law, but residual spin magnetic moment appears already around 100 K, significantly above Curie temperature (Tc), suggesting that short-range ferromagnetic correlations are developed significantly above Tc. The high-field magnetic susceptibility becomes T-independent below TC, indicating that the AF interaction between the substitutional Mn (Mnsub and interstitial Mn (Mnint) ions, which becomes strong as the Mn concentration x increases, exists and that the amount of the Mnint affects Tc. The present experimental findings should give valuable insight into the inhomogeneous ...

Energy Technology Data Exchange (ETDEWEB)

Using the Relativistic Mean Field Theory (RMF) it is shown that different proton fraction which is directly connected with the neutron excess and with the asymmetry of the system affects proto-neutron stars parameters and changes their composition. The obtained form of the equation of state allows to construct the mass-radius relations and shows that the increasing asymmetry creates more compact stars. The inclusion of {delta} meson together with nonlinear vector meson interaction terms and magnetic field make this effect even stronger.

Energy Technology Data Exchange (ETDEWEB)

In the present paper, a possible interaction region layout of the VLEPP based Photon Linear Collider (PLC) with ultimate luminosity is discussed. In order to remove spent electron beams, the crab-crossing scheme is used. The detector is protected from produced pairs and secondary particles by means of the detector magnetic field and a shielding mask. ((orig.)).

KoreaScience (Korea)

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Energy Technology Data Exchange (ETDEWEB)

DC resistivity, dc magnetization, and specific heat of eight Sc{sub 5}Co{sub 4}Ge{sub 10}-type crystal-structure compounds R{sub 5}T{sub 4}Ge{sub 10} for R = Dy, Ho, Er, Tm, and T = Rh and Ir are presented. The resistivity, single-crystal magnetization, and specific-heat results show that in all those compounds, the magnetic moments order antiferromagnetically in the c direction at low temperature. However, in the Er and Tm compounds, the magnetizations along x-y hard directions do not show any anomalies above 2.0 K. This suggests that the ordered Er and Tm ions, which have positive quadrupole coefficients, interact with a crystal field that has an electronic potential valley along the c axis. The fitting of the hard axis magnetizations to Curie-Weiss law suggests that the resulting antiferromagnetic-like {theta} reflects the strength of the crystal-field torque ...

CERN Document Server

It is shown that the physical interpretation of Elie Cartan three-dimensional space torsion as couple asymmetric stress, has the effect of damping, previously Riemannian unstable Couette planar shear flow, leading to stability of the flow in the Lagrangean sense. Actually, since the flow speed is inversely proportional to torsion, it has the effect of causing a damping in the planar flow atenuating the instability effect. In this sense we may say that Cartan torsion induces shear viscous asymmetric stresses in the fluid, which are able to damp the instability of the flow. The stability of the flow is computed from the sectional curvature in non-Riemannian three-dimensional manifold. Marginal stability is asssumed by making the sectional non-Riemannian curvature zero, which allows us to determine the speeds of flows able to induce this stability. The ideas discussed here show that torsion plays the geometrical role of ...

International Nuclear Information System (INIS)

The future use of single-molecule magnets in applications will require the ability to control and manipulate the spin state and magnetization of the magnets by external means. There are different approaches to this control, one being the modification of the magnets by adsorption of small ligand molecules. In this paper we use iron phthalocyanine supported by an Au(111) surface as a model compound and demonstrate, using x-ray photoelectron spectroscopy and density functional theory, that the spin state of the molecule can be tuned to different values (S #approx# 0, 1/2, 1) by adsorption of ammonia, pyridine, carbon monoxide or nitric oxide on the iron ion. The interaction also leads to electronic decoupling of the iron phthalocyanine from the Au(111) support. (fast track communication)

Energy Technology Data Exchange (ETDEWEB)

A theoretical analysis of formation and symmetry transformations is presented for Wigner molecules with N = 2,..., 20 electrons confined in quantum dots at high magnetic fields. Using the unrestricted Hartree-Fock method with the multicentre Gaussian basis, we have found that Wigner molecules with N {>=} 6 abruptly change their shape and symmetry with an associated jump in the first derivative of the ground-state energy, i.e. they undergo phase transitions. In particular, the phases of the Wigner molecules obtained just after emerging from the maximum-density droplet (MDD) phase possess a different symmetry from that formed at a high magnetic field. We show that the properties of the electron-electron interaction energy demonstrate very well both the breakdown of the MDD and the quasi-classical character of the Wigner molecule in the high magnetic field. Possible mechanisms of the MDD decay are ...

Energy Technology Data Exchange (ETDEWEB)

By ab-initio calculation we show that the (Ga,Fe)N ground state may be changed from anti-ferromagnetic to ferromagnetic by acceptor defect like Ga vacancies. The electronic structures are calculated by using the Korringa-Kohn-Rostoker (KKR) method combined with coherent potential approximation (CPA). We show that we can increase the magnetic moment of Fe in p-type GaN by oxygen co-doping. Mechanism of exchange interactions between magnetic ions in p-type (Ga,Fe)N is also studied. The effect of external magnetic field on the electronic structure of (Ga, Fe)N and p-type (Ga, Fe)N is investigated.

CERN Document Server

One of the most challenging problems in Opportunistic Spectrum Access (OSA) is to design channel sensing-based protocol in multi secondary users (SUs) network. Quality of Service (QoS) requirements for SUs have significant implications on this protocol design. In this paper, we propose a new method to find joint policies for SUs which not only guarantees QoS requirements but also maximizes network throughput. We use Decentralized Partially Observable Markov Decision Process (Dec-POMDP) to formulate interactions between SUs. Meanwhile, a tractable approach for Dec-POMDP is utilized to extract sub-optimum joint policies for large horizons. Among these policies, the joint policy which guarantees QoS requirements is selected as the joint sensing strategy for SUs. To show the efficiency of the proposed method, we consider two SUs trying to access two-channel primary users (PUs) network modeled by discrete Markov chains. ...

Science.gov (United States)

The effect of 50 Hz and 60 Hz (frequencies of current distribution) and 20 kHz to 50 kHz (frequencies of induction cooktop) magnetic interference on implanted pacemakers have been assessed with the present generation of device technology. Sixty patients implanted in 1998 and 1999 with dual chamber pacemakers from 9 different manufacturers were monitored with telemetry while passing through, and standing between a system of two coils. They generated a 50 Hz or a 60 Hz magnetic field at 50 microT. Then, patients used a cooktop at different power. The recordings were made with the standard setting of "medically correct" sensing parameters chosen for the patients. Then pacemakers were reprogrammed to the unipolar mode, with the highest atrial (A) and ventricular (V) sensitivity that did not induce muscular inhibition while moving. Between each exposure (50 Hz, 60 Hz or 20 kHz to 50 kHz), the pacemaker programmation was ...

Energy Technology Data Exchange (ETDEWEB)

The Atmospheric Radiation Monitor (ARM) uninhabited aerospace vehicle (UAV) program aims to develop measurement techniques and instruments suitable for a new class of high altitude, long endurance UAVs while supporting the climate community with valuable data sets. Using the Scaled Composites Proteus aircraft, ARM UAV participated in Mixed-Phase Arctic Cloud Experiment (M-PACE), obtaining unique data to help understand the interaction of clouds with solar and infrared radiation. Many measurements obtained using the Proteus were coincident with in-situ observations made by the UND Citation. Data from M-PACE are needed to understand interactions between clouds, the atmosphere and ocean in the Arctic, critical interactions given large-scale models suggest enhanced warming compared to lower latitudes is occurring.

CERN Document Server

Neutrino emission drives neutron star cooling for the first several hundreds of years after its birth. Given the low energy ($\\sim$ keV) nature of this process, one expects very few nonstandard particle physics contributions which could affect this rate. Requiring that any new physics contributions involve light degrees of freedom, one of the likely candidates which can affect the cooling process would be a nonzero magnetic moment for the neutrino. To illustrate, we compute the emission rate for neutrino pair bremsstrahlung in neutron-neutron scattering through photon-neutrino magnetic moment coupling. We also present analogous differential rates for neutrino scattering off nucleons and electrons that determine neutrino opacities in supernovae. Employing current upper bounds from collider experiments on the tau magnetic moment, we find that the neutrino emission rate can exceed the rate through neutral current electroweak ...

International Nuclear Information System (INIS)

The isostructural uranium monopnictides and monochalcogenides have become prototype systems in actinide research with respect to their unusual magnetic properties. We have investigated the origins in the electronic structure of the variation in magnetic behavior as the degree of 5f-electron localization changes from localized to itinerant on going up the pnictogen or chalcogen column, thus decreasing the U-U separation. We have applied a synthesis of: (1) A phenomenological theory of orbitally driven magnetic ordering which includes both the hybridization-induced and the RKKY exchange interactions on an equal footing, and (2) Ab initio electronic structure calculations, based on the linear-muffin-tin-orbital method, allowing a first-principles evaluation of the parameters entering the model Hamiltonian. We have investigated systematically characteristic trends and changes of the 5f-state resonance ...

Energy Technology Data Exchange (ETDEWEB)

The grain boundary crystallographic misorientations of magnetic-pulse-welded (MPW) aluminum alloy (AA) 6061-T6 in linear and tubular configurations were examined using the electron backscattered diffraction (EBSD) technique. A refined structure of heavily deformed grains with higher grain boundary angles was observed in linear welds. Significant spalling was observed away from the joints, in the interior of tubular welds. The results show the complex interaction of shock waves with the materials during this impact welding process.

International Nuclear Information System (INIS)

Single-crystalline CeRh_2Si_2 and CePd_2Si_2 were grown by the Czochralsky pulling method and the temperature dependence of magnetic susceptibility was investigated. The crystalline electric field (CEF) states in each compound were determined by considering the tetragonal CEF Hamiltonian with mean-field approximation. Interactions between Ce"3"+ ion and the surrounding ligands in CeRh_2Si_2 turned out to be strong and highly anisotropic in comparison to CePd_2Si_2. (orig.)

International Nuclear Information System (INIS)

We present differential scanning calorimetry (DSC), X-ray diffractometry, in situ Moessbauer spectroscopy (MS), and transmission electron microscopy (TEM) studies in Metglas ribbons subjected to different heat treatments. The temperature evolution of the hyperfine field H_h_f(T) and the Curie temperature (T_c) of the amorphous phase are determined. The magnetic field originally present in the amorphous phase has a 'normal' behavior, in the sense that it can be described by the Weiss molecular field theory. The total angular momentum of the iron atoms turns out to be 5/2 and this implies Fe"3"+ in which the electronic spins are uncoupled. When the samples are maintained near T_c (#approx#673 K), three new magnetic phases are detected in the Moessbauer spectra, indicating an onset of a crystallization process well below the first crystallization temperature (T_X_1), as determined by DSC (#approx#820 K). The ...

CERN Document Server

Relativistic strongly magnetized winds outflowing from fast-rotating compact objects like millisecond pulsars with surface magnetic fields of $\\sim 10^{15}-10^{16}$ G are plausible sources of cosmological $\\gamma$-ray bursts. In such winds, there are at least three regions where extremely powerful X-ray and $\\gamma$-ray emission may be generated. The first radiating region is the wind photosphere that is at a distance of $\\sim 10^9$ cm from the compact object. The second radiating region is at a distance of $\\sim 10^{13}-10^{14}$ cm. In this region, the striped component of the wind field is transformed into large-amplitude electromagnetic waves. The third radiating region is at a distance of $\\sim 10^{16}-10^{17}$ cm, where deceleration of the wind due to its interaction with an ambient medium becomes important. Radiation from all these regions is considered.

International Nuclear Information System (INIS)

Measurements are made on the principal magnetic susceptibilities and anisotropies of praseodymium selenate octahydrate single crystals in the temperature range 90 to 300 K. Although the effective magnetic moment is close to the free ion value, the anisotropy is quite high at room temperature. A least sequares fit of the Curie-Weiss law to the observed average susceptibility yields -36.5 K as the paramagnetic Curie temperature. An analysis of the results with a crystal field (CF) of D_4 symmetry, explains the observed results quite well. The CF and the spin-orbit interaction matrix is block diagonalized in the complete 33 dimensional basis of the "3H term in order to obtain the Stark energies and their eigenstates. Intermediate coupling effects are also considered. The ground state being a singlet, the g-factors are absent. Some predictions on the electronic heat capacity and the electronic quadrupole splitting are made in ...

International Nuclear Information System (INIS)

The magnetic scattering spectra of RAgSb_2 (R = Ho, Er, Tm) intermetallic compounds are measured and their crystal electric field parameters are determined using inelastic neutron scattering. It is revealed that the ground state is a nonmagnetic singlet for the HoAgSb_2 compound, a Kramers doublet with a strongly anisotropic g factor for the ErAgSb_2 compound, and a quasi-doublet (random doublet) characterized by an extremely anisotropic g factor for the TmAgSb_2 compound. The exchange interaction is estimated in the molecular field approximation. The magnetic properties of the RAgSb_2 compounds are analyzed in terms of the energy level schemes and eigenfunctions determined in this study. The calculated anisotropic magnetic susceptibilities for all compounds are in good agreement with the experimental data obtained for single crystals.

Energy Technology Data Exchange (ETDEWEB)

The Senior Committee on Environmental, Safety, and Economic Aspects of Magnetic Fusion Energy (ESECOM) has assessed magnetic fusion energy's prospects for providing energy with economic, environmental, and safety characteristics that would be attractive compared with other energy sources (mainly fission) available in the year 2015 and beyond. ESECOM gives particular attention to the interaction of environmental, safety, and economic characteristics of a variety of magnetic fusion reactors, and compares them with a variety of fission cases. Eight fusion cases, two fusion-fission hybrid cases, and four fission cases are examined, using consistent economic and safety models. These models permit exploration of the environmental, safety, and economic potential of fusion concepts using a wide range of possible materials choices, power densities, power conversion schemes, and fuel cycles. The ESECOM ...

Energy Technology Data Exchange (ETDEWEB)

Research performed at the Lawrence Livermore National Laboratory on the equilibrium and stability of a new class of ambient-temperature passive bearing systems is described. The basic concepts involved are: (1) Stability of the rotating system is only achieved in the rotating state. That is, disengaging mechanical systems are used to insure stable levitation at rest (when Earnshaw`s theorem applies). (2) Stable levitation by passive magnetic elements can be achieved if the vector sum of the force derivatives of the several elements of the system is net negative (i.e. restoring) for axial, transverse, and tilt-type perturbations from equilibrium. To satisfy the requirements of (2) using only permanent magnet elements we have employed periodic ``Halbach arrays.`` These interact with passive inductive loaded circuits and act as stabilizers, with the primary forces arising from axially symmetric ...

Energy Technology Data Exchange (ETDEWEB)

16 papers are presented covering: remote sensing - an aid to environment management; remote sensing application; monitoring environmental changes over iron ore mining areas; monitoring and management of environmental degradation due to geological factors; use of Landsat multispectral scanner data in environmental monitoring; geotechnical engineering problems with abandoned limestone mines; photogrammetric monitoring of mining environment; slope monitoring in open cast mines using close range remote sensing method; geobotanical remote sensing and mineral prospecting; geographical information in study of geo-environment through remote sensing; and alteration mapping in cuprite mining district.

Energy Technology Data Exchange (ETDEWEB)

The existence of a narrow peak of electron state density in A-15 is explained by a strong electron-phonon interaction that brings about the polaron narrowing of zone. In the supposition of weak and intermediate bond, the analytical expression for the critical transition temperature is found that corre lates Tsub(c) with phonon spectrum. The model permits to explain Tsub(c) correlation with the number of electrons per atom, temperature direction of resistance, value and temperature dependence of magnetic susceptibility and electron thermal capacity.

International Nuclear Information System (INIS)

A review of the information on the electron and phonon spectra in the A-15 compounds and Chevrel phase superconductors obtained from nuclear magnetic resonance, heat capacity, and Moessbauer effect experiments is presented. Relationships of the Fermi energy electrons and the soft phonons to the strength of the electron-phonon interaction are discussed.

Energy Technology Data Exchange (ETDEWEB)

Electromagnetic effects excited by intense relativistic electron beams in plasmas are investigated using a two-dimensional particle code. The simulations with dense beams show large magnetic fields excited by the Weibel instability as well as sizeable electromagnetic radiation over a significant range of frequencies. The possible relevance of beam plasma instabilities to the laser acceleration of particles is briefly discussed. 6 refs., 4 figs.

Energy Technology Data Exchange (ETDEWEB)

The temperature dependence of the spontaneous magnetization of epitaxial iron films with a thickness ranging from d=20 to 200nm has been measured. The films are grown on GaAs (100) substrates which are covered by a 150nm thick silver (100) buffer layer. For three-dimensional BCC iron it was observed already in 1929 that saturation of the spontaneous magnetization for T->0 is perfectly described by a T{sup 2} power law. On the other hand, for thin two-dimensional (2D) iron films a T{sup 3/2} law has been established in many recent experimental investigations. In our iron films grown on diamagnetic silver, this dimensionality change occurs at a thickness between d=100 and 200nm. Comparison of the here-observed T{sup 3/2} coefficients with those on iron films grown on paramagnetic tungsten (110) shows that the 2D interactions are {approx}20 times larger in the films on tungsten. Recent results on Fe films which are ...

International Nuclear Information System (INIS)

The polycrystalline samples of Y_2_-_xHo_xO_3 (0.10#<=#x#<=#1.80) were synthesized by ceramic technology. The X-ray powder diffraction data were collected and the crystal structures were refined by the Rietveld method for the samples Y_2_-_xHo_xO_3 (x=0.00, 0.20, 0.40, 1.20, 1.80, 2.00). Holmium ions Ho"3"+ were randomly distributed over two cationic sites 8b and 24d in the space group Ia3 in all refined structures. Cation-anion-cation bonds important for superexchange interaction were determined. Magnetic susceptibility measurements were done by the Faraday method in the temperature range 290 to 620 K and a behaviour in accordance with the Curie-Weiss law was obtained. The molar Curie's constants linearly depend on concentration. The effective magnetic moments of Ho"3"+ ions were smaller than the free ion value. The Curie-Weiss paramagnetic temperatures indicated antiferromagnetic interaction. ...

Energy Technology Data Exchange (ETDEWEB)

Electron trapping in crossed electric and magnetic fields is an important mechanism by which electrical discharges can develop in low pressure gases. The authors report observations of discharges produced by this mechanism around a spherical anode in two space simulation chambers, namely the Space Plasma Interaction Experiment (SPIE) at the University of Maryland, and the NASA-Lewis B-2 chamber. They have identified two types of discharges in these experiments. In the B-2 chamber, the breakdown takes the form of a runaway dischage with spherical topology, limited only by the ability of the power supply to provide the current. In the SPIE chamber this type of discharge also occurs, in addition to a low current toroidal discharge which is observed at higher magnetic fields. They present measurements of both types of discharge and show how the trapping effect of the magnetic field together with secondary ...

Science.gov (United States)

... relaxation and a sense of well-being. Warm whirlpool baths, molten paraffin application to the hands and ...

KoreaScience (Korea)

Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Activities and results are reported of a project to investigate the application of remote sensing technology developed for the LACIE, AgRISTARS, Forestry and other NASA remote sensing projects for the environmental monitoring of strip mining, industrial pollution, and acid rain. Following a remote sensing workshop for EPA personnel, the EOD clustering algorithm CLASSY was selected for evaluation by EPA as a possible candidate technology. LANDSAT data acquired for a North Dakota test sight was clustered in order to compare CLASSY with other algorithms.

Science.gov (United States)

... INTERMEDIATE TO THE CENTRALIZERS IS A SENSING SECTION COMPRISED OF MULTIPLE EDDY CURRENT PROBES ON FLEXIBLE ...

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

International Nuclear Information System (INIS)

The first essential before embarking on the radiation-hardening of electrical insulation - mostly magnet coils - in any beam line application is to obtain a reliable estimate of the dose to the components. These are examples ( switchyards at SLAC and LAMPF) where the degree of hardness specified was much higher than was required. Although experience shows that the cost premium for substantial radiation - hardening is of the order of 10%, it has also become clear that well - designed beam line have negligible losses: hardening is required only in the vicinity of targets, collimators or other beam - intercepting devices. Where the beam is deliberately scraped, local shielding will minimize the associated radiation in the surroundings. Electron machines have their own special problems due to synchrotron radiation, so certainly coils and other electrical equipment should be kept away from the beam bend - plane. Because proton beams interact with ...

Energy Technology Data Exchange (ETDEWEB)

The aim of this thesis is to study the coherent transport in semiconducting-superconducting junctions. The SnPb-GaAs system has been studied. It has been shown that the behaviour of this junction is controlled by the disordered area induced by the annealing of the connection near the interface. For a few resistant junction, a conductance anomaly under the gap has been observed and has been explained by a mesoscopic effect in the limit of the very high disorders. The conductance of more resistant junctions has only been bound to the properties of the very disordered area of the semiconductor. The part of the electron-electron interactions on the phase coherence length and on the conductance has been studied. The evolving of the correction of the conductance due to interactions in magnetic field has been followed. The effect of the spin degeneration suppression in CdTe and the GaAs sign inversion in Shubnikov de Haas ...

British Library Electronic Table of Contents (United Kingdom)

Wavy interface morphology is observed in Magnetic Pulse Welding (MPW) similarly to that of the Explosion Welding process (EXW). It is recognized that interfacial waves are formed in a periodic manner and have well defined wavelength and amplitude. The phenomenon of wave formation in EXW has been subjected to extensive investigations in which empirical and numerical models have been published. In the present study, a wave formation mechanism for MPW is presented. This wave-creation mechanism was studied by evaluating the influence of sample geometry on wave morphology using stereoscopic optical microscopy. It was found that interfacial waves are formed in a Kelvin-Helmholtz instability mechanism. Reflected shock waves interact with the welding collision point at the weld interface, where in...

Energy Technology Data Exchange (ETDEWEB)

The magnetic susceptibility of the ternary compounds, RPd/sub 2/Si/sub 2/ (where R=Gd, Tb, Dy, Ho and Er) has been measured. GdPd/sub 2/Si/sub 2/ and TbPd/sub 2/Si/sub 2/ order antiferromagnetically at 13 and 20 K respectively; the rest of the compounds do not show clear ordering down to 4.2 K. Palladium carries no moment in these compounds. The De Gennes formula is not obeyed indicating that the exchange interaction between the 4f moments via conduction electrons is not isotropic.

International Nuclear Information System (INIS)

Magnetic properties of polycrystalline samples of RPd_2Si compounds (R = Gd, Tb, Dy, Ho and Er) are presented. The Gd and Tb based compounds are antiferromagnetic with Neel temperatures of 13.5 and 21 K respectively. For both compounds a metamagnetic transition is observed in low field. Moreover, in TbPd_2Si a transition between two different antiferromagnetic phases is observed at 8.5 K. The Dy, Ho and Er based compounds are ferromagnetic with Curie temperatures of 9, 3.5 ad 2.8 K respectively. The observed properties result from indirect exchange interactions and crystal field effects acting on rare earth ions which lie in a very low symmetry site. (author).

Energy Technology Data Exchange (ETDEWEB)

Single-crystalline CeRh{sub 2}Si{sub 2} and CePd{sub 2}Si{sub 2} were grown by the Czochralsky pulling method and the temperature dependence of magnetic susceptibility was investigated. The crystalline electric field (CEF) states in each compound were determined by considering the tetragonal CEF Hamiltonian with mean-field approximation. Interactions between Ce{sup 3+} ion and the surrounding ligands in CeRh{sub 2}Si{sub 2} turned out to be strong and highly anisotropic in comparison to CePd{sub 2}Si{sub 2}. (orig.) 10 refs.

Energy Technology Data Exchange (ETDEWEB)

Concerns are sometimes expressed about an alleged link between exposure to the extremely low frequency electromagnetic fields occurring in proximity to electricity networks or equipment. Transmission lines are specifically mentioned. The underlying physical mechanisms are described by which electric and magnetic fields exist, with particular reference to high voltage transmission lines. Epidemiological and laboratory studies are the two approaches used in research into the subject and the shortcomings inherent in many such studies and the inconsistencies in the results are mentioned. Some of the more recent epidemiological studies are referred to, also the possible interaction mechanisms between fields and the human body. The work of certain international and national bodies which were established to review the results of research into the alleged association between electromagnetic fields and ill-health are reported. (R.P.)

Energy Technology Data Exchange (ETDEWEB)

More than 2,500 Moessbauer spectroscopic studies on minerals have been published since 1960. These papers contain approximately 8,000 sets of Moessbauer mineral data on at least 400 different minerals. This information has been compiled into a database that includes isomer shifts, quadrupole splittings, and magnetic hyperfine interactions at room, liquid nitrogen, and liquid helium temperatures. The database provides a profile of the Moessbauer research performed to date on minerals, including type and locality of minerals investigated, significance of the studies and results, and location of the research facilities. The data and information are available both in printed and magnetic form.With the establishment of this resource, the Moessbauer Effect Data Center has begun a systematic evaluation of the Moessbauer mineral data. It is anticipated that this resource can be used for the identification of minerals as powder ...

International Nuclear Information System (INIS)

A detailed treatment is introduced to measure the dynamic stability of the relativistic electrons in a self-amplified spontaneous emission free-electron laser (FEL) system, which includes the numerical approach of the Kolmogorov entropy (entropy-like quantity), the general equations of motion for a charged particle and the method of monitoring the simulation accuracy. Numerical experiments reveal a new phenomenon that there exists the possibility of the transition from chaotic to non-chaotic phase-space trajectories of the strongly relativistic electrons due to the effect of their self-fields. The adiabatic magnetic field of a one-dimensional wiggler may have a slight influence on the electron transportation in the absence of the FEL fields, but substantially affects the dynamic stability of the electrons in the process of the FEL interaction. Moreover, the laser fields diminish the dynamic stability of the electrons as the FEL ...

Energy Technology Data Exchange (ETDEWEB)

Colloidal nanocrystals attract significant interest due to their potential applications in electronic, magnetic, and optical devices. Nanocrystal supercrystals (NCSCs) are particularly appealing for their well ordered structure and homogeneity. The interactions between organic ligands that passivate the inorganic nanocrystal cores critically influence their self-organization into supercrystals, By investigating the mechanical properties of supercrystals, we can directly characterize the particle-particle interactions in a well-defined geometry, and gain insight into both the self-assembly process and the potential applications of nanocrystal supercrystals. Here we report nanoindentation studies of well ordered lead-sulfide (Pbs) nanocrystal supercrystals. Their modulus and hardness were found to be similar to soft polymers at 1.7 GPa and 70 MPa respectively and the fractures toughness was 39 KPa/m1/2, revealing the ...

International Nuclear Information System (INIS)

We have constructed a mathematical model that describes the coherent spontaneous radiation of a macroscopically filled exciton mode. We have demonstrated qualitatively ways in which a coherent subsystem of excitons can be formed. When this occurs under the influence of an external coherent source, exciton free induction occurs, while in the case of a spontaneous transition of the excitons to a coherent state through freezing of the reservoir of intermolecular interactions superradiance occurs. We have concluded that superradiance in the system of Frenkel excitons is possible under the influence of the non-Dicke mechanisms of self-induction of correlations, when the dipole transition moments of the individual atoms are coupled into a single macroscopic effective spin through their electrostatic interaction, this being analogous to the ordering of magnetic dipole moments in a ferromagnet.

Science.gov (United States)

Laser devices are currently in widespread use in particular by armed forces for different tasks. Electro-optical sensors as well as unprotected human eyes are extremely sensitive to laser radiation and can be permanently damaged from direct or reflected beams. Laser damage depends on the interaction between the laser beam and the atmosphere in which it traverses. The atmospheric conditions, including the range, terrain features, turbulence, and atmospheric particulates, may alter the laser's effect on different electro-optical devices and systems. When a laser beam passes through the atmosphere the optical turbulence affects the beam. As a result, temporal intensity fluctuations (scintillations) or spatial variations in intensity within a beam cross-section occur. Atmospheric scintillations pose a safety problem because an observer or sensor can be subjected to the risk of a localized irradiance (local focusing effect) much greater than that which would occur in a ...

International Nuclear Information System (INIS)

... parameters magnetic fields magnetic properties magnetization monocrystals

Energy Technology Data Exchange (ETDEWEB)

This conference provided a forum for more than 500 delegates from industry, government universities and research centres to share their professional knowledge on research and development that affects all sectors of geotechnical engineering, applied geology and hydrogeology. Accomplishments in the geoenvironmental field were also highlighted. The geotechnical sessions were entitled: pile foundations and load testing; excavations and special foundation issues; reinforced soil and soil-structure interactions; advances in modelling, constitutive issues; advances in modelling, consolidation and other applications; advances in modelling, discrete elements and slope stability; embankments and dams; landfills and barriers; fundamental soil mechanics; soil mechanics and ground movement; GIS and remote sensing; landslides and slopes; cone penetration tests and liquefaction assessment; rock mechanics; engineering geology; geoenvironmental sustainability; ...

Energy Technology Data Exchange (ETDEWEB)

At the conclusion of polarized proton commissioning in February 1986, protons with an average polarization of 45%, momentum of 21.7 GeV/c, and intensity of 2 x 10/sup 10/ protons per pulse, were extracted to an external polarimeter at the Brookhaven AGS. In order to maintain this polarization, five intrinsic and nearly forty imperfection depolarizing resonances had to be corrected. An apparent interaction between imperfection and intrinsic resonances occurring at very nearly the same energy was observed and the correction of imperfection resonances using ''beat'' magnetic harmonics discovered in the previous AGS commissioning run was further confirmed.

International Nuclear Information System (INIS)

A triangular antiferromagnet UNi_4B experiences a partially disordered state, in which two-thirds of U 5f moments order in a vertex-like structure and one-third of U 5f moments remain paramagnetic. Magnetization and NMR measurements of UNi_4B have been performed to study the dynamical properties of U magnetic moments in the partially disordered state. The value of the effective moment above T_N derived from the fitting of the Curie-Weiss law suggests a significant crystal field splitting and the Kondo effect. The Weiss temperature was also estimated to be -28 K, which suggests that the exchange interaction is antiferromagnetic. Furthermore, the exchange interaction estimated from the relaxation rate T_1"-"1 above 50 K is 18 K, which is close to the Weiss temperature. These results suggest that the dominant interactions between U moments are antiferromagnetic in the basal plane. The ...

Energy Technology Data Exchange (ETDEWEB)

Superparamagnetic MFe{sub 2}{sup 3+}O{sub 4} (M=Mn{sup 2+}, Fe{sup 2+} and Co{sup 2+}) inverse spinel ferrite (ISF) nanoparticles with narrow size distribution having average diameters of 6-8 nm were synthesized by a diol reduction of organic metals and the surface was modified to be hydrophilic by coating with succimer. Magnetic resonance imaging (MRI) contrast enhancement by dipolar coupling defined interactions between the synthesized ISFs and protons in the bulk water was investigated with initial susceptibility, magnetization and anisotropy of the succimer-coated ISFs. The relaxivity ratios, r{sub 2}/r{sub 1}, for MnFe{sub 2}O{sub 4}, Fe{sub 3}O{sub 4} and CoFe{sub 2}O{sub 4} were measured to be 12.2, 23.1 and 62.3, respectively, which demonstrate the potential usefulness of these magnetic nanoparticles as T{sub 2} contrast agents for MRI.

CERN Document Server

We introduce a methodology for analysis of multiwavelength data from X-ray selected BL Lac (XBL) objects detected in the TeV regime. By assuming that the radio--through--X-ray flux from XBLs is nonthermal synchrotron radiation emitted by isotropically-distributed electrons in the randomly oriented magnetic field of a relativistic blazar jet, we obtain the electron spectrum. This spectrum is then used to deduce the synchrotron self-Compton (SSC) spectrum as a function of the Doppler factor, magnetic field, and variability timescale. The variability timescale is used to infer the comoving blob radius from light travel-time arguments, leaving only two parameters. With this approach, we accurately simulate the synchrotron and SSC spectrum of flaring XBLs in the Thomson through Klein-Nishina regimes. Photoabsorption by interactions with internal jet radiation and the intergalactic background light (IBL) is included. Doppler ...

International Nuclear Information System (INIS)

We report the results of neutron-diffraction experiments on CeM_2Si_2 (M = Ag,Au,Pd,Rh) which were performed to explore the role of valence fluctuations and 4f hybridization in the magnetic ordering of cerium compounds. All four order antiferromagnetically, the first three exhibiting structures consisting of ferromagnetic layers with moments perpendicular to the layers, which are believed to be characteristic of 4f-4f interactions mediated through hybridization with conduction electrons. CePd_2Si_2 has an anomalously small moment (0.62#mu#/sub B/) in the ordered state. CeAg_2Si_2 exhibits an incommensurate longitudinal, static magnetization wave with moment and propagation direction along the a axis. The fourth compound, CeRh_2Si_2, has the highest known transition temperature (39 K) reported for cerium ordering; it exhibits another second-order transition at 27 K to a complex commensurate structure with modulated moments. ...

Science.gov (United States)

Magnetic particles have become very promising materials for drug delivery. However, preparation of magnetite particles with high surface area, biocompatibility, strong magnetic response, and suitable particle size still remains a major challenge. In this report, magnetite nanocrystal clusters with high surface areas were fabricated through a solvothermal process by introducing ammonium acetate as a porogen and trisodium citrate as a surface modification agent. The porosity, which was controlled by the reactant concentration, has been investigated in detail. The surface area of the nanocrystal clusters was as high as 141?m(2) g(-1) . Ibuprofen, as a model drug, was entrapped into the magnetite carriers. The interfacial interaction between the carboxylic groups on the drug molecules and the carboxylate groups on the carriers enhanced the loading efficiency. Low cytotoxicity in MCF-7 cell and in vitro constant drug release ...

Science.gov (United States)

We have measured the transverse asymmetry A{sub T{sup '}} in the quasielastic {sup 3}He-vector(e-vector,e{sup '}) process with high precision at Q{sup 2} values from 0.1 to 0.6 (GeV/c){sup 2}. The neutron magnetic form factor G{sub M}{sup n} was extracted at Q{sup 2} values of 0.1 and 0.2 (GeV/c){sup 2} using a nonrelativistic Faddeev calculation which includes both final-state interactions (FSI) and meson-exchange currents (MEC). Theoretical uncertainties due to the FSI and MEC effects were constrained with a precision measurement of the spin-dependent asymmetry in the threshold region of {sup 3}He-vector(e-vector,e{sup '}). We also extracted the neutron magnetic form factor G{sub M}{sup n} at Q{sup 2} values of 0.3 to 0.6 (GeV/c){sup 2} based on plane wave impulse approximation calculations.

International Nuclear Information System (INIS)

We present first-time measurements of the Fermi surface and low-energy electronic structure of intermetallic compounds Gd_2PdSi_3 and Tb_2PdSi_3 by means of angle-resolved photoelectron spectroscopy (ARPES). We show that the Fermi surface in both compounds consists of an electron barrel at the #GAMMA# point surrounded by spindle-shaped electron pockets originating from the same band, with the band bottom of both features lying at 0.5 eV below the Fermi level. From the experimentally measured band structure, we estimate the momentum-dependent RKKY coupling strength and demonstrate that it is peaked at the 1/2#GAMMA# K wave vector. Comparison with neutron diffraction data from the same crystals shows perfect agreement of this vector with the propagation vector of the low-temperature in-plane magnetic order, thereby demonstrating the decisive role of the Fermi surface geometry in explaining the complex magnetically ordered ground state of ternary ...

Energy Technology Data Exchange (ETDEWEB)

The potential of different multitemporal and multispectral airborne and spaceborne remote sensing methods for assessment and monitoring of the lignite open-cast mining areas are discussed in this chapter. Emphasis is placed on the successful use of different remote sensing data in variable vegetation structures for dumped sediments with different mineralogical and geochemical properties and for hydrochemical properties of the residual lakes. Multiple remote sensing data are a cost and time efficient tool for the assessment of environmental impacts, supervising of reclamation activities as well as for long term monitoring of the mining area. The airborne data are well suited for large scale detailed research and mapping in smaller sites and the satellite data for the overview scale 1:50 000. An integrated remote sensing-GIS-system including all field and lab data, DTM and other graphical data, improve ...

Energy Technology Data Exchange (ETDEWEB)

This thesis is in the field of gas emission control from automobile and stationary sources. Out of the possible approaches to the elimination of pollutant gases, such as nitrogen oxides (NO{sub x}), one consists in the selective catalytic reduction (SCR) of these NO{sub x} on a suitable heterogeneous catalyst. Ammonia or hydrocarbons are employed as reducing agents. The most important catalysts active in the SCR of NO{sub x} are based on ions of transition metal either supported on several oxides or dispersed in zeolites. The catalysts have been characterized by electron magnetic resonance techniques (EPR, ENDOR, ESEEM) and the interaction of catalysts with nitrogen oxides, with reducing and poisoned agents have been followed with the same techniques. Copper dispersed on alumina and its interaction with both NO and ammonia has been investigated. Also the interaction between both water and ammonia with ...

Science.gov (United States)

It was thus actually the fourth stage of the rocket assembly. ... package, and several temperature sensors - was mounted in the cross-lattice frame. ... Earth's geomagnetic field and incoming charged particles from the Sun and extra-solar space. ...

KoreaScience (Korea)

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KoreaScience (Korea)

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Energy Technology Data Exchange (ETDEWEB)

The subject of this volume is remote sensing for environmental monitoring and resource management. This session is divided in eight parts. First part is on general topics, methodology and meteorology. Second part is on geology, environment and land cover. Third part is on disaster monitoring. Fourth part is on operational status of remote sensing. Fifth part is on coastal zones and inland waters. Sixth and seventh parts are on forestry and agriculture. Eighth part is on instrumentation and systems. (A.B.). refs., figs., tabs.

Energy Technology Data Exchange (ETDEWEB)

Focuses on the application of remote sensing techniques to the study of coal waste mounds. The situation at the coal waste mounds in Fukuoka, Japan is cited. Guidelines on film parameters, photographic keys and tasks required to inventory, monitor and manage coal waste mounds in Japan are addressed. Application of photogrammetry, remote sensing, aerial photography and satellite imagery techniques in monitoring spoil banks is reviewed. Applicability of the techniques is discussed. 24 refs.

Energy Technology Data Exchange (ETDEWEB)

Strong perpendicular anisotropy systems consisting of Co/Pt multilayer stacks that are antiferromagnetically coupled via thin Ru or NiO layers have been used as model systems to study the competition between local interlayer exchange and long-range dipolar interactions [1,2]. Magnetic Force Microscopy (MFM) studies of such systems reveal complex magnetic configurations with a mix of antiferromagnetic (AF) and ferromagnetic (FM) phases. However, MFM allows detecting surface stray fields only and can interact strongly with the magnetic structure of the sample, thus altering the original domain configuration of interest [3,4]. In the current study they combine magnetometry and state-of-the-art soft X-ray transmission microscopy (MXTM) to investigate the external field driven FM phase evolution originating from the domain boundaries in such antiferromagnetically coupled perpendicular ...

Science.gov (United States)

... Title : Refining the Magnetic Forming Capability. ... Abstract : The purpose of this project was to refine the in-house magnetic forming capability. ...

Science.gov (United States)

... Examples include magnetic forming tools, magnetic shielding, magnetohydrodynamic propulsion systems, and various magnetic containment ...

Energy Technology Data Exchange (ETDEWEB)

One- and two-dimensional NMR techniques have been used to investigate the solution structures of (2S,6S,11S,15S)-2,6,11,15-tetramethyl-1,4,7,10,13,16-hexaoxacyclooctadecane (I) and (2R,3R,11R,12R)-2,3,11,12-tetramethyl-1,4,7,10,13,16-hexaoxyacyclooctadecane (II) macrocycle complexes of CaCl{sub 2} and Ca(NO{sub 3}){sub 2} in CDCl{sub 3}. Previous chiroptical studies of these and similar crown complexes by circularly polarized luminescence (CPL), total luminescence (TL), and circular dichroism (CD) spectroscopy have shown that the macrocycle asymmetric carbons in these complexes constrain the ring such that the sense of the ring twist in the S chiral ring complexes is opposite to that in the R chiral ring complexes. These studies have also shown that there is an added chirality element in the di- and trivalent (alkaline earth and lanthanide metal, respectively) nitrate complexes of I and II associated with the twist of the nitrate anions relative to one another as ...

Energy Technology Data Exchange (ETDEWEB)

The paper reports on the results of a study of the synthesis conditions effects on magnetic and transport properties of nanosized layers of high-T{sub c} diluted magnetic semiconductors (DMS), such as Ge:Mn, Si:Mn and Si:Fe, fabricated by laser-plasma deposition over a wide range of the growth temperature, T{sub g}=(20-550) deg. C on single-crystal GaAs or Al{sub 2}O{sub 3} substrates. Ferromagnetism of the layers was detected by measurement data of the magneto-optical Kerr effect, anomalous Hall effect, negative magnetoresistance and ferromagnetic resonance (FMR) at 5-500 K. The optimum growth temperature, T{sub g}, for Si:Mn/GaAs layers with T{sub c}{approx}400 K is shown to be about 400 deg. C. The Si:Mn/Al{sub 2}O{sub 3} layers with 35% of Mn have the metal-type of conductivity with manifestation of magnetization up to room temperature. Different types of uniformly doped structures and digital alloys have been ...

International Nuclear Information System (INIS)

Many important advances in the physics of strongly correlated electron systems have been driven by the development of new materials: for instance the filled skutterudites MT4X12 (M=alkali metal, alkaline earth, lanthanide, or actinide; T=Fe, Ru, or Os; X=P, As, or Sb), certain lanthanide and actinide intermetallic compounds such as URu2-xRexSi2 and CeTIn5 (T=Co, Rh, or Ir), and layered oxypnictides and related materials. These types of complex multinary d- and f-electron compounds have proven to be a vast reservoir of novel strongly correlated electron ground states and phenomena. In these materials, the occurrence of such a wide range of ground states and phenomena arises from a delicate interplay between competing interactions that can be tuned by partial or complete substitution of one element for another, as well as the application of pressure, and magnetic fields, resulting in rich and complex electronic phase diagrams in the hyperspace of ...

British Library Electronic Table of Contents (United Kingdom)

Abstract Coordination compounds [Ru(acac)2(Q)] (acac=acetylacetonate; Q=o-benzoquinone) were prepared as complexes 1 (Q=o-benzoquinone), 2 (Q=3-methoxy-o-benzoquinone), 3 (Q=4-methyl-o-benzoquinone), and 4 (Q=3,5-di-tert-butyl-o-benzoquinone). The structures of 1 and 2 were determined to reveal a RuIII/o-benzosemiquinone formulation, supported by analysis of experimental data (spectroscopy, magnetism of 1) and by DFT calculations. The S=1 ground state calculated for 1 stands in contrast to the spin-paired analogues with arylimino-o-benzosemiquinonato and diimino-o-benzoquinone ligands. The close contacts of about 5.3- possible between semiquinone O atoms of different molecules in the crystal allow for intermolecular spin-spin interactions and an overall complex magnetic behavior. One quasi...

Energy Technology Data Exchange (ETDEWEB)

Isobaric contaminants are often problematical in accelerated negative ion beams for research at certain radioactive ion beam (RIB) and accelerator mass spectrometry (AMS) facilities since their presence in low-intensity rare isotopic beams seriously compromise experimental results. This article describes a non-resonant, laser-based photo-detachment apparatus for use at these facilities, which, according to calculations efficiently removes isobaric contaminants from these beams. The advantage of the system for isobaric contaminant removal over other systems proposed to date lies in its ability to efficiently capture easily transportable energetic negative ion beams with low, intermediate or high energy spreads by a superconducting solenoid magnetic field. The ability to change the diameter of captured beams by adjusting the magnetic field strength permits optimum control of the radial overlap of the laser/negative ion beam profiles over an ...

Science.gov (United States)

The neutron-rich Mn isotopes from A=59 to 63 have been studied through multi-nucleon transfer reactions by bombarding a {sup 238}U target with a beam of {sup 70}Zn at an energy of E{sub lab}=460 MeV. Prompt {gamma} rays measured by the CLARA array have been identified unambiguously for each nucleus, using coincidence relationships with ions detected in the high-acceptance magnetic spectrometer PRISMA. The new data extends the knowledge of the low-lying level structure of Mn isotopes, which is discussed in terms of the systematics of the region. Results are compared with large-scale shell-model calculations using different effective interactions and valence spaces.

International Nuclear Information System (INIS)

Electrodynamic properties of processes involving charged tachyons are considered in connection with the real superluminal Lorentz transformations. These transformations are interpreted without making use of a tachon corridor and so that the interaction of tachyons from subluminal sources with ordinary matter is Lorentz invariant. Transformations of the electromagnetic fields are deduced from the extended principle of relativity. They are necessary in order to obtain the field equations that are satisfied by fields obeying Maxwell equations relative to superluminal inertial frames with respect to subluminal inertial frames. The field equations allow one to get the dependence of the field energy density and its current on the field strengths. The resulting equations are applied in a discussion of plane electromegnetic waves, sent out by a superluminal source. The obtained electrodynamics allows the existence of charged tatric charges do not behave as ...

British Library Electronic Table of Contents (United Kingdom)

Summary Humans discount the value of future rewards over time. Here we show using functional magnetic resonance imaging (fMRI) and neural coupling analyses that episodic future thinking reduces the rate of delay discounting through a modulation of neural decision-making and episodic future thinking networks. In addition to a standard control condition, real subject-specific episodic event cues were presented during a delay discounting task. Spontaneous episodic imagery during cue processing predicted how much subjects changed their preferences toward more future-minded choice behavior. Neural valuation signals in the anterior cingulate cortex and functional coupling of this region with hippocampus and amygdala predicted the degree to which future thinking modulated individual preference fu...

Energy Technology Data Exchange (ETDEWEB)

Four general topics are covered in respect to the natural space radiation environment: (1) particles trapped by the earth`s magnetic field, (2) cosmic rays, (3) radiation environment inside a spacecraft, (4) laboratory radiation sources. The interaction of radiation with materials is described by ionization effects and displacement effects. Total-dose effects on MOS devices is discussed with respect to: measurement techniques, electron-hole yield, hole transport, oxide traps, interface traps, border traps, device properties, case studies and special concerns for commercial devices. Other device types considered for total-dose effects are SOI devices and nitrided oxide devices. Lastly, single event phenomena are discussed with respect to charge collection mechanisms and hard errors. (GHH)

International Nuclear Information System (INIS)

The local Yb3+ magnetic susceptibility tensor was recently measured in the frustrated pyrochlore compound Yb2Ti2O7 by means of in-field polarized neutron scattering in a single crystal. A very anisotropic effective exchange tensor was derived for the Yb3+ ion. Using this result, we reinterpret here the data for the powder susceptibility in Yb2Ti2O7. We show that, in the case of a well-isolated Kramers doublet with anisotropic g and exchange tensors, the inverse susceptibility for a powder sample does not strictly obey a Curie-Weiss law at low temperature. We discuss the consequences regarding the paramagnetic Curie temperature, usually taken as a measure of the exchange/dipolar interaction, and the exotic 'slow fluctuation' ground state of Yb2Ti2O7. (fast track communication)

International Nuclear Information System (INIS)

During the operation of a tokamak, the first wall elements suffer very high heat fluxes. Heat is removed by internal cooling by means of water, helium or fluid metal. The resulting inhomogeneous temperature field cause internal stresses which, due to the pulsed operation are of cyclic nature. Additional mechanical stresses in the first wall may be caused by disruptions or vertical plasma movements. During theses events high currents are induced in the metallic part of the first wall which by their interaction with the magnetic field of the tokamak lead to mechanical forces. These electromechanical stresses may lie beyond the yield stress of the structural material. From the interaction of thermal and mechanical forces, a complex stress state is achieved which under certain circumstances may lead to premature failure and/or to progressive plastic deformations (ratcheting). In order to study the boundary conditions for the ...

Energy Technology Data Exchange (ETDEWEB)

The interaction of cis-diamminediaquoplatinum(II) nitrate with adenosylcobalamin and a series of alkylcobalamins was studied by carbon-13 nuclear magnetic resonance spectroscopy and by electronic spectroscopy. With these cobalamins cis-(Pt(NH/sub 3/)/sub 2/(OH/sub 2/)/sub 2/)/sup 2 +/ forms adducts in which N(3) of the 5,6-methylbenzimidazole moiety is co-ordinated to platinum(II) rather than to cobalt(III) of the corrin. The chemical shifts of the 5'-methylene carbon of adenosylcobalamin-platinum adduct and of the Co-methyl carbon of the methylcobalamin-platinum adduct are characteristic of these cobalamins in the base-off form. Furthermore, these cobalamin-platinum complexes have visible spectra identical to those of the cobalamins in acidic solution. The /sup 13/C NMR spectrum of the adenosylcobalamin-platinum complex suggests the presence of a second adduct in which platinum(II) complexes are co-ordinated to both the N(3) of the ...

Science.gov (United States)

Radial Halbach magnetic bearings have been investigated as part of an effort to develop increasingly

Science.gov (United States)

Necessary theoretical foundation is given for the treatment of magnetic stresses applied to

KoreaScience (Korea)

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Science.gov (United States)

Discussion of an electrohydraulic and magnetic forming process

Energy Technology Data Exchange (ETDEWEB)

Magnetic separation of several classes of antibiotics was investigated using electrochemical magnetic seeding. Electrocoagulation with a sacrificial anode followed by addition of magnetite particles was applied for the magnetic seeding of antibiotics. With electrochemical magnetic seeding using an iron anode, tetracycline antibiotics (oxytetracycline, chlortetracycline, doxycycline and tetracycline) and cephalosporin antibiotic (cefdinir) were rapidly removed from synthetic wastewater by magnetic separation using a neodymium magnet. Iron and aluminium anodes were suitable for magnetic seeding of the antibiotics. The results indicated that the ability of antibiotics to form strong complex with iron and aluminium allowed the higher removal by magnetic separation. This method would be appropriate for rapid treatment of ...

Energy Technology Data Exchange (ETDEWEB)

An Eulerian/Langrangian model was developed to study the two-phase flow in a two-dimensional, axisymmetric, direct-injection diesel engine, under motored and firing conditions. The liquid phase was tracked in a Lagrangian sense using discrete droplet packets (DDP). The gaseous phase was solved using an implicit, iterative, finite-difference, scheme of the control volume variety. Gaseous-phase turbulence was modeled using a compressible two-equation k/epsilon model. Turbulence effects on the liquid phase were modeled by superimposing a randomly oriented turbulent eddy velocity proportional to the root of the turbulent kinetic energy, on each packet's mean relative velocity. Droplet-droplet interactions were neglected. The general knowledge obtained during validation studies, was used to simulate the direct-injection two-stroke diesel engine under motored conditions. The simulation showed that by beginning of the injection, (15/sup 0/ ...

Scientific Electronic Library Online (English)

Abstract in english Human organism is interpenetrated by the world of microorganisms, from the conception until the death. This interpenetration involves different levels of interactions between the partners including trophic exchanges, bi-directional cell signaling and gene activation, besides genetic and epigenetic phenomena, and tends towards mutual adaptation and coevolution. Since these processes are critical for the survival of individuals and species, they rely on the existence of a c (more) omplex organization of adaptive systems aiming at two apparently conflicting purposes: the maintenance of the internal coherence of each partner, and a mutually advantageous coexistence and progressive adaptation between them. Humans possess three adaptive systems: the nervous, the endocrine and the immune system, each internally organized into subsystems functionally connected by intraconnections, to maintain the internal coherence of the system. The three adaptive ...

International Nuclear Information System (INIS)

Iron doped semiconducting nanoparticles Sn1-xFexO2 with x=0, 0.001, 0.002, 0.003, 0.004, 0.01 and 0.03 were prepared by a sol-gel method. The X-ray diffraction, Transmission Electron Microscopy measurements confirm the rutile structure with no impurity phase. The three characteristic lines of electron spin resonance (ESR) are observed in the doped samples for all compositions, which is a clear evidence for rhombic Fe3+ in rutile phase. The line width of ESR increases with increase in Fe concentration due to induced disorder. The spin-pumping effect is observed at temperatures below 250 K for the samples with x=0.01 and 0.03. However, based on the Curie-Weiss susceptibility, iron is in paramagnetic state and is subject to weak antiferromagnetic interaction. Blue shift in the optical band gap is observed with increase in the Fe content. -- Graphical abstract: The ESR spectra reveal that the nature of Fe in Sn1-xFexO2 samples is isolated rhombic Fe3+-ion in rutile ...

Science.gov (United States)

The rapidly growing field of remote sensing is beginning to supply massive amounts of high resolution imagery of the earth and other planets. ...

Science.gov (United States)

... The Aum Shinryko sarin gas attack on the Ginza Subway line in Tokyo in 1995 brought home to the Japanese a sense of immediate vulnerability. ...

Science.gov (United States)

metric temperatures has been prepared showing the surface water temper- ... occasion, gray levels show different densities for similar water temper- ...

Energy Technology Data Exchange (ETDEWEB)

The symposium reviewed the use of electronics in mining today. Subjects covered include control systems; remote sensing; telemetry; data transmission; microprocessors and transportation systems. 15 papers have been abstracted separately.

UK PubMed Central (United Kingdom)

Acidosis in the gastrointestinal tract can be both a physiological and pathological condition. While gastric acid serves digestion and protection from pathogens, pathological acidosis is associated...Full Text Available

International Nuclear Information System (INIS)

R_2PdSi_3 compounds have been found to exhibit rich magnetic phenomena arising from the interplay between RKKY interaction, crystal electric field effects and geometric frustration due to the derived hexagonal AlB_2 structure. The observed crystallographic superstructure further complicates the CEF level scheme. Inelastic neutron scattering measurements on single crystals of Tm_2PdSi_3 and Er_2PdSi_3 have been performed at the cold triple axis spectrometer PANDA in FRM-II. Both compounds order antiferromagnetically at T_N=7 K and 2.1 K respectively; Er_2PdSi_3 undergoes a second phase transition at T_2=2 K. Several low lying CEF excitations (below 10 meV) were observed. The intensity of the lowest excitation show strong directional dependence (in HK0 plane for Er_2PdSi_3 and in HHL plane for Tm_2PdSi_3), from which the details of the transitional matrix could be deduced. Measurements in magnetic fields up to 13 T show ...

Energy Technology Data Exchange (ETDEWEB)

This paper addresses the stability aspects of several successful dc superconducting magnets such as large bubble chamber magnets, and magnets for the Mirror Fusion Test Facility and MHD Research Facility. Specifically, it will cover Argonne National Laboratory 12-Foot Bubble Chamber magnets, the 15-foot Bubble Chamber magnets at Fermi National Laboratory, the MFTF-B Magnet System at Lawrence Livermore National Laboratory, the U-25B Bypass MHD Magnet, and the CFFF Superconducting MHD magnet built by Argonne National Laboratory. All of these magnets are cooled in pool-boiling mode. Magnet design is briefly reviewed. Discussed in detail are the adopted stability critera, analyses of stability and disturbance, stability simulation, and the final results of magnet ...

International Nuclear Information System (INIS)

We investigate the magnetic braking of the core of an axisymmetric cloud whose rotation axis is parallel to the mean direction of the magnetic field. (author).

Energy Technology Data Exchange (ETDEWEB)

The magnetic fluid is a colloidal suspension of magnetite in kerosene, prepared by a low-cost process. Separation is accomplished in an open trough filled with magnetic fluid. A magnetic field is established in the fluid, by energizing an electromagnet having poles on each side of the trough. Due to the design of the magnet poles and air gaps, the magnetic field is strongest at the bottom, about 10,000 oersteds, and uniformly decreases in strength to about 2000 oersteds at the top of the fluid. Therefore, the magnetic field gradient increases with depth. The magnetic force attracts the entire separation medium (magnetic fluid) creating a reaction force of equal magnitude and acting in the opposite direction. This reaction created within a magnetic fluid/magnetic field combination ...

CERN Document Server

The Design of an Interactive Online Help Desk in the Alexandria Digital Library

CERN Document Server

An Introduction to the Standard Theory of Electroweak Interactions (4/4)

CERN Document Server

An Introduction to the Standard Theory of Electroweak Interactions (2/4)

Energy Technology Data Exchange (ETDEWEB)

Real-time horizon sensing on continuous mining machines is becoming an industry tool. Installation and testing of production-grade Horizon Sensor (HS) systems continued this quarter at Monterey Coal Company (ExxonMobil), Mountain Coal Company West Elk Mine (Arch), and Ohio Valley Coal Company (OVC). Monitoring of system function, user experience, and mining benefits is ongoing. All horizon sensor components have finished MSHA (U.S.) and IEC (International) certification.

Energy Technology Data Exchange (ETDEWEB)

A portable fiber optic detector that senses the presence of specific target chemicals by electrostatically attracting the target chemical to an aromatic compound coating on an optical fiber. Attaching the target chemical to the coated fiber reduces the fluorescence so that a photon sensing detector records the reduced light level and activates an appropriate alarm or indicator.

Energy Technology Data Exchange (ETDEWEB)

An ASTER (advanced spaceborne thermal emission and reflection radiometer) is one of the image sensors. It is to be installed in an earth survey polar orbit platform satellite, EOS-AM1, which is to be launched in 1998, and it is going to start its operation. Data observed by the thermal infrared remote sensing of ASTER include the spectral emissivity, and the spectral emission reflectivity which is expressed by the function of temperature. It is required to overcome technical problems how to extract the spectral emissivity from the observed data. The spectral emissivity extracted from the remote sensing data by the MMD method, measured for samples collected in Cuprite area, Nevada, and/or measured at sampled points were compared to each other and discussed. The hemisphere spectral reflectivity, which is indirect spectral emissivity, agreed well with the direct spectral emissivity. Data suggesting the establishment of Kirchhoff`s law were ...

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International Nuclear Information System (INIS)

... radiations isotopes magnetic moments nuclear cascades nuclear properties

Science.gov (United States)

... in the design of such devices as fusion reactors, magnetohydrodynamic generators, magnetically levitated vehicles, magnetic forming devices, and ...

Science.gov (United States)

Decoupling force exerted by magnetic forming Be coil assembly on metallic plate during forming

International Nuclear Information System (INIS)

This paper traces the development and progress of magnetic suspension systems and magnetic bearings in the USSR. The paper describes magnetic bearings for turbomachines, magnetic suspension systems for vibration isolation, some special measuring devices, wind tunnels, and other applications. The design, principles of operation, and dynamic characteristics of the system are presented.

International Nuclear Information System (INIS)

Electron and ion beam dynamics of the PF-1000 facility were investigated for the first time at its upper energy limit (?1 MJ) in relation to neutron emission, the pinch's plasma ('target') characteristics and some other parameters with the help of a number of diagnostics with ns temporal resolution. Special attention was paid to the temporal and the spatial cross correlations of different phenomena. Results of these experiments are in favour of a neutron emission model based on ion beam-plasma interaction with three important features: (1) the plasma target is hot and confined during a few 'inertial confinement times'; (2) the ions of the main part of the beam are magnetized and entrapped around the pinch plasma target for a period longer than the characteristic time of the plasma inductive storage system and (3) ion-ion collisions (both fusion collisions, due to head-on impacts and Coulomb collisions) are responsible for neutron emission. ...

CERN Document Server

We present a fully relativistic formalism for describing neutrino-induced $\\Delta$-mediated single-pion production from nuclei. We assess the ambiguities stemming from the $\\Delta$ interactions. Variations in the cross sections of over 10% are observed, depending on whether or not magnetic-dipole dominance is assumed to extract the vector form factors. These uncertainties have a direct impact on the accuracy with which the axial-vector form factors can be extracted. Different predictions for $C_5^A(Q^2)$ induce up to 40-50% effects on the $\\Delta$-production cross sections. To describe the nucleus, we turn to a relativistic plane-wave impulse approximation (RPWIA) using realistic bound-state wave functions derived in the Hartree approximation to the $\\sigma$-$\\omega$ Walecka model. For neutrino energies larger than 1 GeV, we show that a relativistic Fermi-gas model with appropriate binding-energy correction produces comparable results as ...

Energy Technology Data Exchange (ETDEWEB)

Recent research has shown that biologically inspired approaches to materials synthesis and self-assembly, hold promise of unprecedented atomic level control of structure and interfaces. In particular, the use of organic molecules to control the production of inorganic technological materials has the potential for controlling grain structure to enhance material strength; controlling facet expression for enhanced catalytic activity; and controlling the shape of nanostructured materials to optimize optical, electrical and magnetic properties. In this work, we use organic molecules to modify silver crystal shapes towards understanding the metal-organic interactions that lead to nanoparticle shape control. Using in situ electrochemical AFM (EC-AFM) as an in situ probe, we study the influence of a cationic surfactant cetyltrimethylamminobromide (CTAB) on Ag growth during electrochemical deposition on Ag(100). The results show that the organic ...

CERN Document Server

If the first (PopIII) stars were very massive, their final fate is to collapse into very massive black holes. Once a proto-black hole has formed into the stellar core, accretion continues through a disk. It is widely accepted, although not confirmed, that magnetic fields drive an energetic jet which produces a burst of TeV neutrinos by photon-meson interaction, and eventually breaks out of the stellar envelope appearing as a Gamma Ray Burst (GRB). Based on recent numerical simulations and neutrino emission models, we predict the expected neutrino diffuse flux from these PopIII GRBs and compare it with the capabilities of present and planned detectors as AMANDA and IceCube. If beamed into 1% of the sky, we find that the rate of PopIII GRBs is $\\le 4 \\times 10^6$ yr$^{-1}$. High energy neutrinos from PopIII GRBs could dominate the overall flux in two energy bands [$10^4 - 10^5$] GeV and [$10^5 - 10^6$] GeV of neutrino telescopes. The enhanced ...

International Nuclear Information System (INIS)

The present article outlines major features of the free electron laser (FEL) and reviews research and development of FEL. Relations among the oscillation frequency, electron beam parameters and wiggler parameters, the physical mechanism of amplification and the physical process of saturation are discussed to identify the difference between FEL and other lasers. The report also outlines techniques for accelerators which are used to generate high-quality, high-energy electron beams required for FEL experiments. Techniques to achieve a short wavelength, high output and high efficiency, and applications of FEL are also discussed. FEL consists of an electron accelerator, wiggler and optical resonator. In FEL, electron beams with a relativistic energy interact resonantly with an electromagnetic field to generate coherent electromagnetic waves. Unlike conventional lasers, FEL does not surfer from restrictions on its oscillation frequency associated with atomic, molecular ...

International Nuclear Information System (INIS)

EPR and FT-IR absorption measurements have been performed for xCuO.(100-x)[2Bi2O3.B2O3] glass system, with 0?x?50 mol%. The mode in which the addition of the copper ions influences the structure of 2Bi2O3.B2O3 glass matrix was analyzed. The EPR absorption spectra revealed the presence in the glass structure of Cu2+ ions in axially distorted octahedral environments. EPR data pointed out the simultaneous presence of Cu2+ and Cu+ ionic species in the glasses with x?5 mol%. For x>10 mol%, the Cu2+ ions participate in the superexchange magnetic interactions, which increase with CuO content. The FT-IR spectra showed the presence of some bands that are assigned to vibrations of Bi-O bonds from BiO3 pyramidal and BiO6 octahedral units and B-O bonds from BO3 and BO4 units. The data obtained by these measurements reveal the structural changes in the 2Bi2O3.B2O3 glass matrix by controlled doping of CuO.

CERN Document Server

The CMS detector (Compact Muon Solenoid) is under construction at one of the four proton-proton interaction points of the LHC (Large Hadron Collider) at CERN, the European Organization for Nuclear Research (Geneva, Switzerland). The inner tracking system of the CMS experiment consisting of silicon detectors will have a diameter of 2.4 m and a length of 5.4 m representing the largest silicon tracker ever. About 15000 silicon strip modules create an active silicon area of 200 m2 to detect charged particles from proton collisions. They are placed on a rigid carbon fibre structure, providing stability within the working conditions of a 4 T solenoid magnetic field at ?10oC. Knowledge of the position of the silicon detectors at the level of 100 ?m is needed for an efficient pattern recognition of charged particle tracks. Metrology methods are used to survey tracker subdetectors and the integrated Laser Alignment System (LAS) provides absolute ...

Energy Technology Data Exchange (ETDEWEB)

The flux of cosmic ray antiprotons with kinetic energies between /approximately/1 and 15 GeV is /approximately/5 times greater than the flux predicted on the basis of the leaky-box model. This excess is attributed to secondary antineutron production in compact sources. Because the antineutrons are not confined by the magnetic field of the compact source, they leave the interaction site, decay in interstellar space and account for the apparent excess cosmic ray antiproton flux. The escape and decay of neutrons produced in association with the antineutrons is a source of cosmic ray protons. Observations of the angular variation of the intensity and spectral shape of 100 MeV ..gamma..-rays produced by neutron-decay protons in the reaction p + p ..-->.. ..pi../sup 0/ ..-->.. 2..gamma.. could reveal compact-source cosmic ray production sites. COS-B observations of spectral hardening near point sources, and future high-resolution observations ...

International Nuclear Information System (INIS)

Ammonia adsorption on the external surface of C_3_0B_1_5N_1_5 heterofullerene was studied using density functional calculations. Three models of the ammonia-attached C_3_0B_1_5N_1_5 together with the perfect model were optimized at the B3LYP/6-31G"* level. The optimization process reveals that dramatic influences occurred for the geometrical structure of C_3_0B_1_5N_1_5 after ammonia adsorption; the B atom relaxes outwardly and consequently the heterofullerene distorts from the spherical form in the adsorption sites. The chemical shielding (CS) tensors and nuclear quadrupole coupling constants of B and N nuclei were calculated at the B3LYP/6-311G"*"* level. Our calculations reveal that the B atom is chemically bonded to NH_3 molecule. The B atom in the NH_3-attached form has the largest chemical shielding isotropic (CSI) value among the other boron nuclei. The C_Q parameters of B nuclei at the interaction sites are significantly decreased after ammonia adsorption.

International Nuclear Information System (INIS)

Fully relativistic full-potential density functional calculations with an all-electron linearized augmented plane wave plus local orbitals method have been performed to investigate the electronic and geometric structures of atomic carbon, nitrogen, and oxygen chemisorption on the (1 0 0) surface of #delta#-Pu. For all chemisorption processes, the center adsorption site is found to be the most preferred site with chemisorption energies of 7.964, 7.665, and 8.335 eV for the C, N, and O adatoms, respectively. The respective optimized distances of the C, N, and O adatoms from the surface were found to be 0.26, 0.35, and 0.48 A. The work functions and the net magnet moments, respectively, increased and decreased in all cases compared with the bare #delta#-Pu (1 0 0) surface. In particular, the work function shift is largest for the least preferred top site and lowest for the most preferred center site. A detailed analysis of partial charges inside the atomic spheres, ...

International Nuclear Information System (INIS)

A non-contact method, using magnetic drag force principle, was proposed to design the braking systems to improve the shortcomings of the conventional braking systems. The extensive literature detailing all aspects of the magnetic braking is briefly reviewed, however little of this refers specifically to upright magnetic braking system, which is useful for industries. One of the major issues to design upright magnetic system is to find out the magnetic flux. The changing magnetic flux induces eddy currents in the conductor. These currents dissipate energy in the conductor and generate drag force to slow down the motion. Therefore, a finite element model is developed to analyze the phenomena of magnetic flux density when air gap and materials of track are varied. The verification shows the predicted magnetic flux is within ...

Energy Technology Data Exchange (ETDEWEB)

Typical beam lines are comprised of an assembly of vacuum valves and shutters referred to as a ''front end'', optical elements to monochromatize, focus and split the photon beam, and an experimental area where a target sample is placed into the photon beam and data from the interaction is detected and recorded. Windows are used to separate sections of beam lines that are not compatible with storage ring ultra high vacuum. Some experimental beam lines share a common vacuum with storage rings. Sections of beam lines are only allowed to vent up to atmospheric pressure using pure nitrogen gas after a vacuum barrier is established to protect ring vacuum. The front end may only be bled up when there is no current in the machine. This is especially true on the VUV storage ring where for most experiments, windows are not used. For the shorter wavelength, more energetic photons of the x-ray ring, beryllium windows are used at various beam ...

Science.gov (United States)

Four questions are posed: (1) Is knowledge utilization a rhetorical evocation? (2) Is the conjunction of knowledge with utility part of a cultural system of common sense? (3) Is utility a normative or a descriptive concept? and (4) How does the concept of knowledge utilization figure in the specialized discourse of social scientists? This paper analyzes the concept of knowledge utilization from the perspective of philosophy of language and philosophy of science. Knowledge utilization is a rhetorical evocation that implies concepts of action and knowledge. It is supported by two conceptual fusions. The fusion of value and utility draws on common sense, but does not exhaust colloquial understandings about knowledge and action. The conceptual fusion of knowledge and truth is consistent with common sense but disregards scientific criticism. Both conceptual fusions are thus problematic. But empirical conditions associated with ...

British Library Electronic Table of Contents (United Kingdom)

Remote sensing of total suspended solids (TSS) by satellite techniques in estuaries and bays plays an important role in monitoring water quality over a large area. It is valuable to the management of coastal water environment and ecosystems. In this study, remote sensing mapping of TSS was conducted to investigate the effects of rainstorm events on Apalachicola Bay. A rainstorm event (October 7-8, 2008) was selected for a period when wind speeds were weak and the river inflow was almost steady. TSS mapping of MODIS images before and after the rainstorm event showed substantial increase of TSS induced by the rainstorm. Using an image during low river discharge before the rainstorm as a reference, TSS distribution was mapped by an improved regression model using MODIS image after a rainstorm...

British Library Electronic Table of Contents (United Kingdom)

Abstract People with a physical disability are a population who for a number of reasons may be vulnerable to social isolation. Research into Internet based support sites has found that social support and an online sense of community can be developed through computer mediated communication channels. This study aims to gain an understanding of the benefits that membership of disability specific online communities may have for people with a physical disability. An online survey was administered to a sample of users of such sites (N = 160). Results indicated that users did receive moral support and personal advice through participating in such online communities. Further, results indicated that online social support and feeling a sense of community online were positively associated with partic...

CERN Document Server

We present a method for grouping the synonyms of a lemma according to its dictionary senses. The senses are defined by a large machine readable dictionary for French, the TLFi (Tr\\'esor de la langue fran\\c{c}aise informatis\\'e) and the synonyms are given by 5 synonym dictionaries (also for French). To evaluate the proposed method, we manually constructed a gold standard where for each (word, definition) pair and given the set of synonyms defined for that word by the 5 synonym dictionaries, 4 lexicographers specified the set of synonyms they judge adequate. While inter-annotator agreement ranges on that task from 67% to at best 88% depending on the annotator pair and on the synonym dictionary being considered, the automatic procedure we propose scores a precision of 67% and a recall of 71%. The proposed method is compared with related work namely, word sense disambiguation, synonym lexicon acquisition and WordNet ...

British Library Electronic Table of Contents (United Kingdom)

Luminescent materials are widely used for imaging and sensing owing to their high sensitivity, rapid response and facile detection by many optical technologies. Typically materials must be chemically tailored to achieve intense, photostable fluorescence, oxygen-sensitive phosphorescence or dual emission for ratiometric sensing, often by blending two dyes in a matrix. Dual-emissive materials combining all of these features in one easily tunable molecular platform are desirable, but when fluorescence and phosphorescence originate from the same dye, it can be challenging to vary relative fluorescence/phosphorescence intensities for practical sensing applications. Heavy-atom substitution alone increases phosphorescence by a given, not variable amount. Here, we report a strategy for modulating ...

International Nuclear Information System (INIS)

Several recent experiments on micro- (or nano-) structured samples of ferromagnetic materials are introduced. Magnetization reversal phenomena are investigated on submicron wire samples of trilayer structure using the giant magnetoresistance effect. Domain wall movements are sensitively monitored by resistivity measurements and the velocity of propagation is determined. The contribution of domain wall to the resistivity is argued from the results on artificially designed samples of a spring-magnet system. In circular dots of permalloy, the existence of vortex magnetization is confirmed and the reversal of the vortex core magnetization is studied from magnetic force microscopy measurements. (author)

International Nuclear Information System (INIS)

A new iron phosphate (NH4)4Fe3(OH)2F2[H3(PO4)4] has been synthesized hydrothermally at HF concentrations from 0.5 to 1.2 mL. Single-crystal X-ray diffraction analysis reveals its three-dimensional open-framework structure (monoclinic, space group P21/n (No. 14), a=6.2614(13) A, b=9.844(2) A, c=14.271(3) A, ?=92.11(1)o, V=879.0(3) A3). This structure is built from isolated linear trimers of corner-sharing Fe(III) octahedra, which are linked by (PO4) groups to form ten-membered-ring channels along [1 0 0]. This isolated, linear trimer of corner-sharing Fe(III) octahedra, [(FeO4)3(OH)2F2], is new and adds to the diverse linkages of Fe polyhedra as secondary building units in iron phosphates. The trivalent iron at octahedral sites for the title compound has been confirmed by synchrotron Fe K-edge XANES spectra and magnetic measurements. Magnetic measurements also show that this compound exhibit a strong antiferromagnetic exchange below TN=17 K, ...

Energy Technology Data Exchange (ETDEWEB)

The wavefunction of a particle extends into the classically forbidden barrier region of the potential energy surface. The consequence of this partial delocalisation is the phenomenon of quantum tunnelling, an effect which enables a particle to penetrate a potential barrier of magnitude greater than the energy of the particle. The tunnelling probability is an exponential function of the particle mass. The effect is therefore an important contribution to the behaviour of light atoms, in particular the proton. The hydrogen bond has long been appreciated to be an essential component of many biological and chemical systems, and the proton transfer reaction in the hydrogen bond is fundamental to many of these processes. The proton behaviour in the hydrogen bonds of benzoic acid, acetylacetone and calix-4-arene has been studied. A variety of techniques, both experimental and computational, were adopted for the study of the three hydrogen bonded systems. The complementary spectroscopic ...

Energy Technology Data Exchange (ETDEWEB)

Many important advances in the physics of strongly correlated electron systems have been driven by the development of new materials: for instance the filled skutterudites MT{sub 4}X{sub 12} (M=alkali metal, alkaline earth, lanthanide, or actinide; T=Fe, Ru, or Os; X=P, As, or Sb), certain lanthanide and actinide intermetallic compounds such as URu{sub 2-x}Re{sub x}Si{sub 2} and CeTIn{sub 5} (T=Co, Rh, or Ir), and layered oxypnictides and related materials. These types of complex multinary d- and f-electron compounds have proven to be a vast reservoir of novel strongly correlated electron ground states and phenomena. In these materials, the occurrence of such a wide range of ground states and phenomena arises from a delicate interplay between competing interactions that can be tuned by partial or complete substitution of one element for another, as well as the application of pressure, and magnetic fields, resulting in rich and complex electronic ...

Energy Technology Data Exchange (ETDEWEB)

Point-contact (PC) investigations on the title compound in the normal and superconducting (SC) state (T{sub c}{approx_equal}10.6 K) are presented. The T-dependence of two SC gaps in TmNi{sub 2}B{sub 2}C determined by Andreev-reflection spectroscopy deviates from the BCS behavior in displaying a maximum at about T{sub c}/2. Additional evidence for the presence of a 2nd gap half as large as the main gap is given. For the first time ''reentrant'' features were found in the Andreev-reflection spectra measured in magnetic fields. The PC spectroscopy of the fermion-boson interaction in TmNi{sub 2}B{sub 2}C reveals a pronounced phonon maximum at 9.5 meV and a more smeared one around 15 meV, while at higher energies the PC spectra are almost featureless. Additionally, the intense peak slightly above 3 meV observed in the PC spectra of TmNi{sub 2}B{sub 2}C, is presumably caused by crystalline-electric-field ...

International Nuclear Information System (INIS)

We investigate a two-orbital Anderson lattice model with Ising orbital intersite exchange interactions on the basis of a dynamical mean field theory combined with the static mean field approximation of intersite orbital interactions. Focusing on Ce-based heavy-fermion compounds, we examine the orbital crossover between two orbital states, when the total f-electron number per site n_f is #approx#1. We show that a 'meta-orbital' transition, at which the occupancy of two orbitals changes steeply, occurs when the hybridization between the ground-state f-electron orbital and conduction electrons is smaller than that between the excited f-electron orbital and conduction electrons at low pressures. Near the meta-orbital critical end point, orbital fluctuations are enhanced and couple with charge fluctuations. A critical theory of meta-orbital fluctuations is also developed by applying the self-consistent renormalization theory of itinerant electron ...

Energy Technology Data Exchange (ETDEWEB)

Potassium clusters arrayed in zeolite A are known to show ferromagnetic properties at low temperature. The origin of the spontaneous magnetization has been explained by a model of spin-canting in an antiferromagnetically ordered state. The direct information for the magnetic structure, however, has not been obtained so far. In the present work, we measure the neutron powder diffraction by using pulsed neutron source at KEK-KENS below and above the Curie temperature. No significant temperature-dependence was, however, obtained within the statistical errors, namely, magnetic scattering could not be detected separately. We also estimate the intensity of magnetic scattering by assuming some possible magnetic structures with considering the magnetic form factor of the cluster wave function. The intensity of magnetic scattering is estimated to be ...

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

Energy Technology Data Exchange (ETDEWEB)

Experience with multiwire proportional chambers at high rates at the Argonne Zero Gradient Synchrotron is described. A buildup of silicon on the sense wires was observed where the beam passed through the chamber. Analysis of the chamber gas indicated that the density of silicon was probably less than 10 ppM.

UK PubMed Central (United Kingdom)

Mating signals are often directed at numerous senses and provide information about species identity, gender, receptiveness, individual identity and mate quality. Given the diversity of colourful body...Full Text Available

UK PubMed Central (United Kingdom)

SUMMARYIn voltage-gated sodium, potassium, and calcium channels the functions of ion conduction and voltage sensing are performed by two distinct structural units: the pore domain...Full Text Available

UK PubMed Central (United Kingdom)

This unit presents two basic protocols that offer rapid assessments of anosmia (the absence of a sense of smell) in mice. The buried food test is used to check for the ability to smell volatile...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

A total of 25 papers were presented at the conference in 6 sessions: illumination and communication; power and safety; knowledge based systems; mine-wide monitoring; instrumentation control and automation; remote sensing and imaging.

Energy Technology Data Exchange (ETDEWEB)

The possibility has been explored of using a laser scattering technique to detect the imminent onset of rock activity associated with gas outbursts. The instrument described in this paper provides a sensitive, remote and rapid means of passively monitoring micro-seismic activity at the exposed face.

UK PubMed Central (United Kingdom)

Within the next 30 years, the proportion of urban dwellers will rise from under half to two thirds of the world’s population. Such a shift will entail massive public health consequences,...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundIn the past two decades the east African highlands have experienced several major malaria epidemics. Currently there is a renewed interest in exploring the possibility...Full Text Available

Science.gov (United States)

What happens in the matrix of gender, technology, representation, and culture? This class will explore the theoretical issues raised within this matrix. We will also make sense of the theories through practical experiences with technologies like computers and cameras.

UK PubMed Central (United Kingdom)

Prophylactic knee braces are designed to prevent and reduce the severity of ligamentous injuries to the knee. Conflicting evidence is reported concerning their efficacy. The purpose of this study was...Full Text Available

UK PubMed Central (United Kingdom)

The utility of a two-photon optical fiber fluorescence probe (TPOFF) for sensing and quantifying tumor fluorescent signals was tested in vivo. Xenograft tumors were developed in athymic mice using MCA207...Full Text Available

UK PubMed Central (United Kingdom)

Remote sensing data over North America document the ubiquity of secondary aerosols resulting from a combination of primary biogenic and anthropogenic emissions. The spatial and temporal distribution...Full Text Available

UK PubMed Central (United Kingdom)

Arsenic is one of the most important global environmental pollutants. Here we show that the cyanobacterium Synechocystis sp. strain PCC 6803 contains an arsenic and antimony resistance...Full Text Available

International Nuclear Information System (INIS)

Scanning ion microscopy with polarization analysis (SIMPA) is used to study the spin-resolved surface magnetic structure of nano-sized magnetic systems. SIMPA is utilized for in situ topographic and spin-resolved magnetic domain imaging as well as for focused ion beam (FIB) etching of desired structures in magnetic or non-magnetic systems. Ultra-thin Co films are deposited on surfaces of Si(1 0 0) substrates, and ultra-thin, tri-layered, bct Fe(1 0 0)/Mn/bct Fe(1 0 0) wedged magnetic structures are deposited on fcc Pd(1 0 0) substrates. SIMPA experiments clearly show that ion-induced electrons emitted from magnetic surfaces exhibit non-zero electron spin polarization (ESP), whereas electrons emitted from non-magnetic surfaces such as Si and Pd exhibit zero ESP, which can be used to calibrate sputtering rates in situ. We ...

Energy Technology Data Exchange (ETDEWEB)

A review of the literature was undertaken to determine the potential for development of instrumentation for on-board remote sensing of coal quality. This review report acts as an inventory of commercially available techniques being tested or under development, particularly in the areas of the cutting horizon measurement methods associated with longwall mining equipment and coal/waste monitoring techniques in coal handling systems. While technology is available which can discriminate rocks from coal on a conveyor belt, the literature indicates that this hardware has yet to be adapted to continuous surface mining machines. 23 refs., 18 figs.

Energy Technology Data Exchange (ETDEWEB)

The present invention is a device for a solar heating system having a solar collector, a storage tank connected to the solar collector, a pump for circulating liquid from the tank to the solar collector, a supply of liquid at a temperature above freezing and a connection from the supply of liquid to the solar collector for replacing any liquid lost from said solar collector. The device comprises a sensor for sensing the temperature of liquid in the solar collector, and a valve for bleeding liquid from the solar collector when the sensed temperature falls below a predetermined minimum whereby cool liquid in the solar collector is automatically replaced by liquid at a temperature above freezing.

British Library Electronic Table of Contents (United Kingdom)

An optical fiber methane sensing system utilizing a super-luminescent diode (SLD) in the 1.33-mm band and a fiber Fabry-Perot tunable filter (FFP-TF) is developed. A two-step reference measuring method, which is based on differential absorption technique, is employed; a reference channel is introduced to eliminate the fluctuation of the illuminant spectrum, and the reference wavelength acquired by tuning the FFP-TF is introduced to eliminate the environmental influence. The two-step reference measuring method has improved the reliability and stability of the system. A minimum detectable methane concentration of 0.3% has been experimentally achieved.

Energy Technology Data Exchange (ETDEWEB)

A tutorial account is given of the main characteristics and distinctive features of conceptual magnetic fusion systems employing the magnetic mirror principle. These features are related to the potential advantages that mirror-based fusion systems may exhibit for the generation of economic fusion power.

Energy Technology Data Exchange (ETDEWEB)

An introduction to time-of-flight neutron spectroscopy is presented in the context of the study of magnetic materials. Examples are taken from the class of rare earth and actinide magnetic materials known as `strongly correlated electron` systems. (author) 11 figs., 24 refs.

Energy Technology Data Exchange (ETDEWEB)

The disclosure is directed to an active magnetic regenerator apparatus and method. Brayton, Stirling, Ericsson, and Carnot cycles and the like may be utilized in an active magnetic regenerator to provide efficient refrigeration over relatively large temperature ranges.

Science.gov (United States)

Principle advantages of magnetic forming for part manufacture appear to lie ... to be an area of great potential for the magnetic forming process. We have a ...

International Nuclear Information System (INIS)

Several refrigerators for liquid helium and liquid nitrogen systems have been integrated successfully into IGC manufactured whole body Magnetic Resonance Imaging (MRI) magnet systems. The refrigerators have been tested in systems with magnetic fields of 0.6T to 1.5T. Tests were performed to study the effectiveness of the refrigerators, the magnetic field effects on the refrigerators, the effect of the refrigerators on the field uniformity and magnetic resonance image quality. The interface between the refrigerator and the whole body MRI magnet system cryostat was specifically designed to allow retrofit to the existing IGC magnet systems, while ensuring good heat transfer characteristics and good vibration isolation from the cryostat. The interface between the refrigerator and the cryostat and the refrigerator test results are presented.

International Nuclear Information System (INIS)

The ternary rare earth compound NdRh_4B_4 has been studied by means of critical field, low temperature heat capacity, and static magnetic susceptibility measurements. Features in the upper critical field and heat capacity data at 1.31 K and 0.89 K suggest the occurrence of long-range magnetic order in the superconducting state. The temperature dependence of the static magnetic susceptibility follows a Curie-Weiss law with an effective magnetic moment #mu#sub(eff) = 3.58 +- 0.05 #mu#sub(B) and a Curie-Weiss temperature thetasub(p) = -6.2 +- 1.0 K between 20 K and room temperature. However, magnetization vs. applied magnetic field isotherms suggest the development of a ferromagnetic component in the Nd"3"+ magnetization at low temperatures. (author).

Energy Technology Data Exchange (ETDEWEB)

Highly ordered arrays of Ni nanoholes and Fe{sub 20}Ni{sub 80} antidots have been prepared, respectively, by replica/antireplica processing and sputtering techniques using nanoporous alumina membranes as templates. Geometrical characteristics as nanohole/antidot diameter, interpore distance and the overall hexagonal symmetry of arrays are controlled through the original templates. Experimental data on their hysteresis and magnetic domain structure have been taken by vibrating sample magnetometry and magnetic force microscopy, respectively. An analysis of the magnetization process, resulting magnetic anisotropy and magnetic domain structure is summarized considering the influence of those geometry aspects. In particular, the hexagonal symmetry and the density of nanohole/antidots determine the overall magnetic behavior, which is of interest in future high-density ...

Energy Technology Data Exchange (ETDEWEB)

It is shown that plasma viscosity does not influence the magnetic island rotation directly. Nevertheless, it leads to nonstationarity of the plasma velocity. This nonstationarity is the reason of the viscosity effect on island rotation. (author)

Science.gov (United States)

Effective localization of small magnets against a noisy, real world background can involve various methods to first identify the magnetic fields produced by the magnet of interest, then to filter out background noise, and then to analyze the available magnetic field data to localize the magnet. Here we discuss low cost techniques which allow localization of small magnets with field strengths in the milliGauss range against real world background fields in the range of hundreds of mG, which may be fluctuating by up to tens of mG. Such techniques allow magnet tracking to be used to localize catheters in place of more invasive and expensive methods, e.g. fluoroscopy, for a variety of applications, including drug infusion with peripherally inserted central catheters (PICCs), laser ablation (TMR, PTMR) and introduction of pacemaker leads.

International Nuclear Information System (INIS)

The dynamic response of cylindrical and ring-shaped YBaCuO bulk parts to pulsed magnetic fields is calculated by using small sets of finite elements. Some comparisons with experimental results are provided, and they give confidence in the modelling of the superconducting properties. Transient magnetizations as a function of time and space as well as shapes and absolute values of trapped magnetic flux profiles are presented. The influence of the sample geometry is investigated for different millisecond pulsed magnetization processes. Results are reported for different radial thicknesses and heights, different pulse durations, peak magnetic fields and pulse sequences with and without stepwise cooling. Comparisons concerning the achievable trapped magnetic field and flux are made, and implications for the use of high-temperature superconductor bulk parts as ...

Energy Technology Data Exchange (ETDEWEB)

A nanosuspension of magnetically tagged metronidazole was developed by the solvent displacement method coupled with ultrasonication and was evaluated for its physicochemical properties. The drug release from metronidazole magnetic nanosuspension at pH 1.2 and 7.0 shows maximum correlation coefficient for zero order and Higuchi model, respectively. The anthelmintic activity of the formulated metronidazole magnetic nanosuspension was evaluated on Indian earthworms (Pheretima poi). Metronidazole magnetic nanosuspension at a dose of 10 and 50 mg/ml shortened by 31% and 34%, respectively, the mean time to death of the earthworms when compared against a non-magnetic metronidazole suspension. Thus, the developed metronidazole magnetic nanosuspension showed potent, controlled and targeted drug action and might be a good therapeutic avenue in combating infectious GI ...

Science.gov (United States)

... design, and manufacturing knowledge have been acquired and used to develop an 'in-house' capability for the fabrication of magnetic forming coils ...

Science.gov (United States)

has been generally related to magnetic forming. One of the methods suggested was the following: A "pancake" magnetic coil is placed over a thin aluminum ...

Science.gov (United States)

magnet research at several national laboratories through its Advanced Accelerator Technology Program. The HEP Conductor Development Program, a collaboration among national...