UK PubMed Central (United Kingdom)

The use of sub-nanometer resolution electron density as spatial constraints for denovo and ab-initio structure prediction requires knowledge of protein boundaries...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

We have measured the oxygen positions in LaNiO{sub 3} films to elucidate the coupling between epitaxial strain and oxygen octahedral rotations. The oxygen positions are determined by comparing the measured and calculated intensities of half-order Bragg peaks, arising from the octahedral rotations. Combining ab initio density-functional calculations with these experimental results, we show how strain systematically modifies both bond angles and lengths in this functional perovskite oxide.

International Nuclear Information System (INIS)

In this thesis, a new ab-initio method for molecular dynamics within the framework of density functional theory was developed and implemented. It is strongly related to the projector-augmented-wave method (PAW) by P. Bloechl, but also includes elements of a pseudocharge method proposed by M. Weinert for the full-potential linearized augmented plane wave method (FLAPW). Like the FLAPW-method, the PAW-method is an all-electron method. In the later case, the hamiltonian takes quite a simple form similar to the one obtained when using normconserving Kleinman-Bylander-type pseudopotentials or ultrasoft Vanderbilt pseudopotentials. The PAW-method allows for an efficient calculation of systems containing virtually any element of the periodic table, including those which require high numerical effort when treated using normconserving pseudopotentials (e.g. 2p-elements like oxygen or 3d-transitional metals like copper). In addition, a higher accuracy ...

Energy Technology Data Exchange (ETDEWEB)

This paper presents fundamental researches based on the electronic structure calculations and X absorption spectroscopy, allowing the knowledge on nuclear fuels at an atomic scale. They bring a better understanding of these material behavior to accurate the macroscopic simulation. The calculation methods, the experimental techniques of validation and the ab initio calculations results are detailed. (A.L.B.)

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CERN Document Server

Over the last decade {\\it ab initio} modeling of material properties has become widespread in diverse fields of research. It has proved to be a powerful tool for predicting various properties of matter under extreme conditions. We apply modern computational chemistry and materials science methods, including density functional theory (DFT), to solve lingering problems in the modeling of the dense atmospheres of cool white dwarfs ($T_{\\rm eff}\\rm <7000 \\, K$). Our work on the revision and improvements of the absorption mechanisms in the hydrogen and helium dominated atmospheres resulted in a new set of atmosphere models. By inclusion of the Ly-$\\rm \\alpha$ red wing opacity we successfully fitted the entire spectral energy distributions of known cool DA stars. In the subsequent work we fitted the majority of the coolest stars with hydrogen-rich models. This finding challenges our understanding of the spectral ...

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.

International Nuclear Information System (INIS)

We have performed ab initio calculations on a wide range of small molecules, demonstrating the accuracy and flexibility of an alternative method for calculating the electronic structure of molecules, solids, and surfaces. It is based on the local-density approximation (LDA) for exchange and correlation and the nonlinear augmented-plane-wave method. Very accurate atomic forces are obtained directly. This allows for implementation of Car-Parrinello-like techniques to determine simultaneously the self-consistent electron wave functions and the equilibrium atomic positions within an iterative scheme. We find excellent agreement with the best existing LDA-based calculations and remarkable agreement with experiment for the equilibrium geometries, vibrational frequencies, and dipole moments of a wide variety of molecules, including strongly bound homopolar and polar molecules, hydrogen-bound and electron-deficient molecules, and ...

Energy Technology Data Exchange (ETDEWEB)

This conference was held December 4--8, 1994 in Asilomar, California. The purpose of this meeting was to provide a forum for exchange of state-of-the-art information concerning the prediction of protein structure. Attention if focused on the following: comparative modeling; sequence to fold assignment; and ab initio folding.

UK PubMed Central (United Kingdom)

Electronic and structural properties of antiphase boundaries in group III-V semiconductor compounds have been receiving increased attention due to the potential to integration of optically-active III-V...Full Text Available

International Nuclear Information System (INIS)

We studied the influence of alloying on the structural and electronic properties of the unrelaxed and relaxed Si_1_-_yC_y random alloys by means of ab initio theoretical calculations using two methods: (i) a supercell approach in connection with the plane-wave pseudopotential method; (ii) the full-potential augmented plane-wave plus local orbitals (APW+lo) method. The first method is used to obtain the relaxed atomic structure. The relaxed atomic positions obtained by pseudopotential calculations were used to calculate the band structure via the second method. The local density approximation was used for the exchange and correlation energy density functional. We investigated the lattice parameters and band gap energies. We found that a quite smaller gap appears in the neighborhood of y=0.03125 concentration of C atoms. The band gap shows a large anomalous bowing and is strongly composition dependent. ...

International Nuclear Information System (INIS)

Ab initio calculations of the electronic structure were performed for the silver palladium oxide, Ag_2PdO_2, by the full potential mixed linearized augmented plane wave and augmented plane wave plus local orbitals method (mixed LAPW/APW+lo) within the density functional theory and using the generalized gradient approximation (GGA96, Phys. Rev. Lett. 77 (1996) 3865) for the exchange-correlation potential. The lattice parameters were calculated from the ground-state total energy versus volume curve, and are in good agreement with the available experimental results. Our calculations of band structure predicted that the compound Ag_2PdO_2 has indirect band gap, and the Pd 4d states strongly hybridize with the O 2p states all over the valence bands and conduction bands. The valence bands are composed mainly of Ag, Pd 4d states and O 2p states, while the conduction bands consist mainly of the Pd 4d states and O 2p states. In ...

International Nuclear Information System (INIS)

We report ab initio calculations of positron wave functions in the high-T/sub c/ superconductors YBa_2Cu_3O_7, Bi_2Sr_2CaCu_2O_8, and Tl_2Ba_2CaCu_2O_8 using the general potential linearized augmented plane-wave method. The calculated positron wave functions are fairly insensitive to whether or not electron-positron correlation is included in the calculation for YBa_2Cu_3O_7 and Tl_2Ba_2CaCu_2O_8, but the calculated positron density is quite sensitive to correlation in Bi_2Sr_2CaCu_2O_8. While the positron wave function samples primarily the chain region in YBa_2Cu_3O_7, the results indicate that positrons should be good probes of the Cu-O layer-derived electronic states near the Fermi energy in Tl_2Ba_2CaCu_2O_8 since a large overlap with these states is predicted.

International Nuclear Information System (INIS)

We have measured the lattice relaxation around As in Si at a homogeneous As concentration of 4x10"1"8 cm"-"3 by EXAFS spectroscopy. From the absorption spectra, distances up to the 4th shell could be extracted. A sizeable misfit due to an increased distance is only observed for the 1st shell. Complementing our experimental work we have performed ab initio calculations based on the density functional theory with the WIEN97 package which uses the linearised augmented plane wave method and with the FHI96md program which uses first-principles pseudo-potentials and a plane wave basis set to investigate the size dependence of the super-cells constructed around one substitutional As atom. The calculations yielded good agreement with our EXAFS experiment so that the determined relaxations can be used as a solid basis for further interpretations of derived parameters such as hyperfine interaction parameters in defect complexes.

International Nuclear Information System (INIS)

By using a variational Monte Carlo method, we examine an effective low-energy model for LaFeAsO derived from an ab initio downfolding scheme. We show that quantum and many-body fluctuations near the antiferromagnetic (AF) quantum critical point largely reduce the antiferromagnetic ordered moment. Our derived model not only quantitatively reproduces the small ordered moment in LaFeAsO, but also accounts for the diversity from LaFePO, BaFe_2As_2 to FeTe. Electron correlation is found to determine the observed material dependence. We also find that LaFeAsO is subject to large orbital fluctuations, sandwiched by the AF Mott insulator and weakly correlated metals. The orbital fluctuations and Dirac-cone dispersion hold keys for the diverse magnetic properties. (author)

International Nuclear Information System (INIS)

The structure of ammonium azide (NH_4)N_3 was (re-)determined ab initio from x-ray powder diffraction experiment using synchrotron radiation. We tried to detail and comment the different steps involved in the structure determination. The compound crystallize in the orthorhombic Pmna space group (no.53) with a = 8.937(1) A, b= 3.8070(5) A, c = 8.664(1) A, V = 294.79(7) A"3; Z= 4. It was possible to locate and refine the hydrogen coordinates, in two different approaches, and to establish the H-bonds. The final structural parameters are in good agreement with previous results based on three-dimensional neutron diffraction. (Author)

Science.gov (United States)

Ab initio lattice dynamics based on linear response method are performed for high pressure phase of yttrium to describe electron-phonon coupling and subsequent superconducting behavior. The critical temperature Tc in fcc-Y increases monotonically with pressure up to 9.25 K at 31 GPa, which is quantitatively in excellent agreement with two quasihydrostatic experiments and is qualitatively compatible with recent experiments. The excellent agreement with experiments gives us a better understanding of the effective pseudopotential ?* as well as spectral function ?2(?)F(?) in yttrium. These results demonstrate that there exists strong electron-phonon coupling in Y within the studied pressure regime, and for lower pressure electron correlation becomes stronger. Generally, it is found that superconductivity in yttrium under pressure can be described quantitatively within standard theory of phonon-mediated superconductivity.

Energy Technology Data Exchange (ETDEWEB)

Ab initio planewave pseudopotential method is used to study carbon diffusion and pairing in crystalline silicon. The calculation is performed with a 40 Ry planewave cutoff and 2x2x2 special k-point sampling with a supercell of 64 atoms. It is found that substitutional carbon attracts interstitial Si forming a <001> C interstitial with a large binding energy of 1.45 eV. The interstitial carbon is mobile and can migrate with a migration energy of 0.5 eV. The interstitial carbon can bind further to another substitutional carbon forming a substitutional carbon-interstitutional carbon pair with a binding energy of 1.0 eV. This model is used to understand the effect of high C concentration on the transient enhanced diffusion in Si.

International Nuclear Information System (INIS)

Ab initio total energy calculations within the framework of density functional theory have been performed for atomic hydrogen and oxygen chemisorption on the (0001) surface of double hexagonal packed (dhcp) americium using a full-potential all-electron linearized augmented plane wave plus local orbitals method. Chemisorption energies were optimized with respect to the distance of the adatom from the relaxed surface for three adsorption sites, namely top, bridge, and hollow hcp sites, the ad-layer structure corresponding to the coverage of a 0.25 monolayer in all cases. Chemisorption energies were computed at the scalar-relativistic level (no spin-orbit coupling NSOC) and at the fully relativistic level (with spin-orbit coupling SOC). The two-fold bridge adsorption site was found to be the most stable site for O at both the NSOC and SOC theoretical levels with chemisorption energies of 8.204 eV and 8.368 eV respectively, ...

UK PubMed Central (United Kingdom)

Model phosphate-metal solvation complexes have been studied by ab-initio self-consistent-field techniques. The complexes studied include (RO)2PO2-(R = H or CH3) with Li+, Na+, K+, Be++, Mg++, Ca++,...Full Text Available

International Nuclear Information System (INIS)

Using ab initio (SCF/6-31G) method, mechanisms of proton migrations in methaboric acid dimers have studied. It is shown that in all the dimers considered a cooperative transfer of protons occurs. The calculated values of activation barriers of cooperative proton transfer reactions in the dimers are equal to 28.6 kcal/mol.

International Nuclear Information System (INIS)

Ab initio total energy calculations within the framework of density functional theory have been performed for water molecule adsorption on the (0001) surface of double hexagonal packed americium using a full-potential all-electron linearized augmented plane wave plus local orbitals method (FP-L/APW+lo). Subsequent partial dissociation (OH+H) and complete dissociation (H+O+H) of the water molecule have been examined. The completely dissociated H+O+H configuration exhibit the strongest binding with the surface (3.35 eV), followed by partially dissociated species OH+H (2.23 eV), with all molecular H_2O configurations showing weak physisorption (0.366 eV). For molecular adsorptions, the flat lying orientation of the water molecule if found to be more favorable for majority of the cases. In the case of partial dissociation (OH+H), the vertical orientation of OH molecule with O facing the surface adsorbed at a h3 adsorption site ...

International Nuclear Information System (INIS)

The structural parameters of various Haegg phases (H or M_n_+_1AX_n phases) are studied experimentally by x-ray and electron spectroscopies, x-ray diffraction, and ab initio full potential as well as full mutiple scattering theoretical calculations. Experimentally it was found that the structure of all ternary compounds analyzed herein are relaxed. The values of the lattice parameters and relaxations obtained from ab initio calculations are in excellent agreement with those deduced from the analysis of the experimental data. The bonding scheme has been analyzed and the charge transfer between constituting atoms determined. It is demonstrated that the strength and electrical transport properties in these materials are principally governed by the metallic planes. For the solid solution (Ti_0_._5Nb_0_._5)_2AlC, the most salient result is that the basal planes are corrugated, which could explain the solid ...

International Nuclear Information System (INIS)

The effects of hydrostatic pressure on the electronic band structure of the semiconductor mineral iron pyrite FeS_2 have been investigated theoretically by an ab initio full-potential linearized-augmented plane wave (FPLAPW) method within a local approximation (LDA/GGA) to the density functional theory. The calculations predict that at a pressure of 94.1 GPa the indirect band gap of pyrite FeS_2 vanishes and the material becomes a metal. This is due to the presence of the S-S and Fe-S bonds, which provide novel energy band distortions in the process of attaining the metallic state. Analysis indicates that, under increasing high pressure, the conduction bands (3p_z of sulfur and 3d_x_"2_-_y_"2+3d_x_y of iron) intrude downwards into the valence bands, which are predominantly 3d in nature. At normal pressure, the lattice constant, the bulk modulus, sulfur position parameter u, S-S bond length, and the indirect band gap of ...

Energy Technology Data Exchange (ETDEWEB)

Infrared spectra of bicyclo[1.1.1]pentane (C5H8) have been recorded at a resolution (0.0015 cm-1) sufficient to resolve for the first time individual rovibrational lines. This initial report presents the ground state constants for this molecule determined from the detailed analysis of three of the ten infrared-allowed bands, v14(e?) at 540 cm-1, v17(a2?) at 1220 cm-1, v18(a2?) at 832 cm-1, and a partial analysis of the v11(e?) band at 1237 cm-1. The upper states of transitions involving the lowest frequency mode, v14(e?), show no evidence of rovibrational perturbations but those for the v17 and v18 (a2?) modes give clear indication of Coriolis coupling to nearby e? levels. Accordingly, ground state constants were determined by use of the combination-difference method for all three bands. The assigned frequencies provided over 3300 consistent ground state difference values, yielding the following constants for the ground state (in units of cm-1): B0 = 0.2399412(2), DJ = 6.024(6) x 10-8, ...

Energy Technology Data Exchange (ETDEWEB)

Density functional theory (DFT) calculations using plane-wave methods were performed for Li2TMPO4F, LiTMPO4F, and TMPO4F (TM=V, Mn, Fe, Co, Ni) to address their feasibility as high-voltage cathode materials for Li ion batteries. We computed their structures, average open circuit voltages, and thermal stabilities for step-wise lithiation/delithation (discharge/charge) reactions. The calculations suggest that associated unit cell volume changes are sufficiently small on average that they should not be a significant detriment to the mechanical stability of the cathode. In the nickel case, the calculated volume change deviates from the series by increasing during the first delithiation step. Furthermore, the volume increases for all these materials during the second delithiation step. It appears that the relative volume expansion in the series during delithiation is directly correlated to the degree of d-p rehybridization. Predicted average open circuit voltages ...

Energy Technology Data Exchange (ETDEWEB)

We present ab-initio calculations of the electronic structure of small Fe clusters (1-9 atoms) on Ni(001), Ni(111), Cu(001) and Cu(111) surfaces. Our focus is on the spin moments and their dependence on cluster size and shape. We derive a simple quantitative rule that relates the moment of each Fe atom linearly to its coordination number. Thus, for an arbitrary Fe cluster the spin moment of the cluster and of the individual Fe atoms can be readily found if the positions of the atoms are known. (orig.)

Energy Technology Data Exchange (ETDEWEB)

An essential issue in gallium (Ga)-stabilized fcc-phase plutonium ({delta}-Pu) is the formation of helium (He) voids and bubbles emanating from the radiolytic decay of the Pu. The rate of formation of He voids and bubbles is related to the He-defect formation energies and their associated migration barriers. The size and shape distributions of the bubbles are coupled to these critical migration processes. The values of the defect formation energies, internal pressure, and migration barriers can be estimated from atomistic calculations. Complicating this picture is the destruction of He-filled voids and bubbles by subsequent radiolytic decay events. The present study concerns the construction of the necessary potential energy surfaces for the Pu-He and He-He interactions within the modified embedded atom method (MEAM). Once fully tested, the potentials will be used to estimate the He-defect formation energies and barriers to the migration of these defects for both interstitial and ...

Energy Technology Data Exchange (ETDEWEB)

We present results from a kinetic Monte Carlo simulation of boron transient enhanced diffusion (TED) in silicon. Our approach avoids the use of phenomenological fits to experimental data by using a complete and self-consistent set of values for defect and dopant energetics derived mostly from {ital ab initio} calculations. The results predict that, during annealing of 40 keV B-implanted Si at 800{degree}C, there exists a time window during which all the implanted boron atoms are substitutional. At earlier or later times, the interactions between free silicon self-interstitials and boron atoms drive the growth of boron clusters and result in an inactive boron fraction. The results show that the majority of boron TED takes place during the growth period of interstitial clusters and not during their dissolution. {copyright} {ital 1998 American Institute of Physics.}

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The portion of the potential energy surface (PES) of acetylacetone relevant for the intramolecular proton transfer reaction is studied using ab initio and DFT methods. The best estimate of the barrier governing proton transfer was found to be 3.4 kcal mol{sup -1} at the MP4(FC)/6-311 + G(2d,2p)//MP2(FC)/6-311 + G(2d,2p) level of theory. Six stationary points on the PES were characterized as well as the reaction paths connecting these points. Special attention paid to the pathway of intramolecular proton transfer reveals that the internal rotation of the methyl group adjacent to the carbonyl group and the proton transfer reaction are consecutive processes.

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.

British Library Electronic Table of Contents (United Kingdom)

The transformation mechanism of hexagonal delta phase from the disordered bcc gamma phase has not been reported before in the Zr-rich U-Zr alloy system. With the help of X-ray diffraction, transmission electron microscopy (TEM) and high-resolution TEM analyses it was shown that the gamma to delta conversion takes place by the lattice collapse mechanism of omega transformation. It was also ascertained that a higher aging temperature or time promotes the growth of all four variants of the delta phase within a parent gamma grain. In addition, ab initio electronic structure calculations showed that the bcc to hexagonal transformation, involving partial ordering of the parent bcc phase followed by (111) plane collapse, is energetically favorable.

Energy Technology Data Exchange (ETDEWEB)

We have developed a kinetic Monte Carlo (kMC) simulator that links atomic migration and binding energies determined primarily from first principles calculations to macroscopic phenomena and laboratory time scales. Input for the kMC simulation is obtained from a combination of ab initio planewave pseudopotential calculations, molecular dynamics simulations, and experimental data. The simulator is validated against an extensive series of experimental studies of the diffusion of B spikes in self-implanted Si. The implant energy, dose, and dose rate, as well as the detailed thermal history of the sample, are included. Good agreement is obtained with the experimental data for temperatures between 750 and 950 C and times from 15 to 255 s. At 1050o C we predict too little diffusion after 105 s compared to experiment: apparently, some mechanism which is not adequately represented by our model becomes important at this temperature. Below 1050o C, the ...

Energy Technology Data Exchange (ETDEWEB)

(12/11)CASSCF and (12/11)CASPT2 ab initio electronic structure calculations with both the cc-pVDZ and cc-pVTZ basis sets find that there is a barrier to the very exothermic hydrogen shift that converts singlet methylnitrene, CH{sub 3}N, to methyleneimine, H{sub 2}C{double{underscore}bond}NH. These two energy minima are connected by a transition structure of C{sub s} symmetry, which is computed to lie 3.8 kcal/mol above the reactant at the (12/11)CASPT2/cc-pVTZ//(12/11)CASSCF/cc-pVTZ level of theory. The (12/11)CASSCF/cc-pVTZ value for the lowest frequency vibration in the transition structure is 854 cm{sup {minus}1}, and CASPT2 calculations concur that this a{double{underscore}prime} vibration does indeed have a positive force constant. Thus, there is no evidence that this geometry is actually a mountain top, rather than a transition structure, on the global potential energy surface or that a C{sub 1} pathway of lower energy connects the ...

British Library Electronic Table of Contents (United Kingdom)

We carried out theoretical analyses based on ab initio calculations incorporates in which free energy of the vapor phase is incorporated in order to determine the initial growth kinetics of c-GaN on GaN(001)-(4x1). The feasibility of the theoretical approach had been confirmed by calculations of Ga adsorption-desorption transition temperature and transition beam equivalent pressures on the GaAs(001)-(4x2)b2 surface in our previous work [Y. Kangawa, T. Ito, A. Taguchi, K. Shiraishi, T. Ohachi, Surf. Sci. 493 (2001) 178]. The results of calculations suggest that no Ga adsorption occurs on the initial surface under typical growth conditions but that a Ga adsorption site appears after N adsorption on GaN(001)-(4x1). That is, in the initial growth stage of c-GaN on GaN(001)-(4x1), a N-adsorbed ...

DEFF Research Database (Denmark)

It is well established from experiments in premixed, laminar flames, jet-stirred reactors, flow reactors, and batch reactors that SO2 acts to catalyze hydrogen atom removal at stoichiometric and reducing conditions. However, the commonly accepted mechanism for radical removal, SO2 + H(+M) reversible arrow HOSO(+M), HOSO + H/OH reversible arrow SO2 + H-2/H2O, has been challenged by recent theoretical and experimental results. Based on ab initio calculations for key reactions, we update the kinetic model for this chemistry and re-examine the mechanism of fuel/SO2 interactions. We find that the interaction of SO, with the radical pool is more complex than previously assumed, involving HOSO and SO, as well as, at high temperatures also HSO, SH, and S. The revised mechanism with a high rate constant for H + SO2 recombination and with SO + H2O, rather than SO2 + H-2, as major products of the HOSO + H reaction is in agreement with a range of ...

Energy Technology Data Exchange (ETDEWEB)

The IR double-resonance techniques IR/R2PI (infrared/resonant 2-photon ionization), IR/PIRI (infrared-photo-induced Rydberg ionization) and IR-photodissociation spectroscopy are valuable tools to investigate structure, vibrations, and dynamical processes of neutral and ionic hydrogen-bonded clusters containing aromatic molecules. In this paper we report on the application of the IR double-resonance techniques to determine the NH and OH stretching vibrations of 4-aminophenol and 4-aminophenol(H{sub 2}O){sub 1}, both in the neutral (S{sub 0}) and ionic (D{sub 0}) ground state. All vibrational frequencies obtained for 4-aminophenol and the cluster are compared with the values obtained from ab initio and DFT calculations. In the S{sub 0} state, a trans-linear arrangement of 4-aminophenol(H{sub 2}O){sub 1} is obtained containing an O-H. O hydrogen bond. In the D{sub 0} state an overlay of two spectra can be observed resulting from the trans-linear ...

International Nuclear Information System (INIS)

The atomic structures of calcium sialons Ca_xSi_1_2_-_mAl_mN_1_6 (m = 0.5, 1, 2, 4) with the #alpha#- or #beta#-Si_3N_4-type structure were calculated, using the ab initio DFT approach, including relaxations of both lattice parameters and positions of the atoms. For all m values the #alpha#-Si_3N_4-type structure has a lower energy than the #beta#-type. For m = 1, 2 and 4 the #alpha#-type structure is also stable against decomposition into the metal nitrides, in agreement with experimental data. For m = 0.5 stability becomes uncertain. Al ions prefer positions close to Ca. Rather strong structural relaxations occur around the Ca ion.

Energy Technology Data Exchange (ETDEWEB)

We demonstrate tuning of Schottky energy barriers in organic electronic devices by utilizing chemically tailored electrodes. The Schottky energy barrier of Ag on poly[2-methoxy], 5-(2{prime}-ethyl-hexyloxy)- 1,4-phenylene was tuned over a range of more than 1 eV by using self-assembled monolayers (SAM{close_quote}s) to attach oriented dipole layers to the Ag prior to device fabrication. Kelvin probe measurements were used to determine the effect of the SAM{close_quote}s on the Ag surface potential. {ital Ab} {ital initio} Hartree-Fock calculations of the molecular dipole moments successfully describe the surface potential changes. The chemically tailored electrodes were then incorporated in organic diode structures and changes in the metal/organic Schottky energy barriers were measured using an electroabsorption technique. These results demonstrate the use of self-assembled monolayers to control metal/organic interfacial electronic properties. ...

CERN Document Server

We show that accretion disks, both in the subcritical and supercritical accretion rate regime, may exhibit significant amplitude luminosity oscillations. The luminosity time behavior has been obtained by performing a set of time-dependent 2D SPH simulations of accretion disks with different values of alpha and accretion rate. In this study, to avoid any influence of the initial disk configuration, we produced the disks injecting matter from an outer edge far from the central object. The period of oscillations is 2 - 50 s respectively for the two cases, and the variation amplitude of the disc luminosity is 10^38 - 10^39 erg/s. An explanation of this luminosity behavior is proposed in terms of limit cycle instability: the disk oscillates between a radiation pressure dominated configuration (with a high luminosity value) and a gas pressure dominated one (with a low luminosity value). The origin of this instability is the difference between the heat produced by viscosity and the energy ...

CERN Document Server

The disk around AB Aur was imaged and resolved at 24.6\\,$\\mu$m using the Cooled Mid-Infrared Camera and Spectrometer on the 8.2m Subaru Telescope. The gaussian full-width at half-maximum of the source size is estimated to be 90 $\\pm$ 6 AU, indicating that the disk extends further out at 24.6\\,$\\mu$m than at shorter wavelengths. In order to interpret the extended 24.6\\,$\\mu$m image, we consider a disk with a reduced surface density within a boundary radius $R_c$, which is motivated by radio observations that suggest a reduced inner region within about 100 AU from the star. Introducing the surface density reduction factor $f_c$ for the inner disk, we determine that the best match with the observed radial intensity profile at 24.6\\,$\\mu$m is achieved with $R_c$=88 AU and $f_c$=0.01. We suggest that the extended emission at 24.6\\,$\\mu$m is due to the enhanced emission from a wall-like structure at the boundary radius ...

Energy Technology Data Exchange (ETDEWEB)

Increased nitrogen levels have been correlated with decreased ductility and elevated ductile-to-brittle transition temperature in pressure vessel steels [1]. However, the exact role played by nitrogen in the embrittlement of steels remains unclear. Miller and Burke have reported atom probe ion microscopy findings from neutron-irradiated low-alloy pressure vessel steel showing the presence of a 1 to 2 ruonolayer thick film of Mo, N, and C at prior austenitic grain boundaries (GB's) [2], suggesting a role for nitrogen as an intergranular embrittler. It is of interest for the development of mitigation strategies whether nitrogen must combine with other impurities to form nitride precipitates in order to exert an embrittling effect. Briant et al [1] have associated the embrittling effect of N in steels exclusively with intergranular nitride formation. This association suggests that high nitrogen levels may be acceptable if nitride precipitation at grain boundaries is suppressed. ...

Energy Technology Data Exchange (ETDEWEB)

From the crystal field analysis of optical absorption spectra on monoclinic S.G. P2{sub 1}/c MgNd(BO{sub 2}){sub 5}, where Nd{sup 3+} occupies a single crystallographic position with no symmetry elements, energy level schemes and an expression of the associated wavefunctions for the 4f{sup 3} configuration of Nd{sup 3+} have been derived, considering approximate C{sub 2v} and C{sub s} (C{sub 2}) symmetries. Despite of the low symmetry of Nd{sup 3+}, resulting rms deviations between calculated and experimental levels are very satisfactory. The composition of the crystal field wavefunctions from both sets of phenomenological free-ion and crystal field parameters has been checked through a calculation of the thermal evolution of the paramagnetic susceptibility {chi}, according to the Van Vleck formula. The same simulation was performed with crystal field parameters (CFPs) resulting from the ab initio simple overlap model (SOM), considering the ...

Energy Technology Data Exchange (ETDEWEB)

The total and state-specific electron-ion recombination rate coefficients are obtained for FeI. The calculations are carried out using a new ab initio method that incorporates both the radiative and the dielectronic recombination processes in an unified and self-consistent manner. The computations employ the close coupling approximation and the R-matrix method from atomic collision theory. A 52 state close coupling eigenfunction expansion dominated by the states of the ground 3d{sup 6}4s and excited 3d{sup 7}, 3d{sup 6}4p, 3d{sup 5}4s{sup 2}, and 3d{sup 5}4s4p configurations of FeII are used in the present calculations. The important electron correlation and radiation damping effects are included via explicit coupling of autoionization and radiative channels. This is the first detailed atomic calculation for the recombination rates for FeI. The present rates are considerably higher than the radiative recombination rates being used currently in ...

Energy Technology Data Exchange (ETDEWEB)

In the framework of the search for a ceramic material usable in the radioactive waste storage, uranium and thorium phosphates have been investigated. Their experimental synthesis conditions have been entirely reviewed, they lead to the preparation of four new compounds: U(UO{sub 2})(PO{sub 4}){sub 2}, U{sub 2}O(PO{sub 4}){sub 2}, UCIPO{sub 4}, 4H{sub 2}O, and Th{sub 4}(PO{sub 4}){sub 4}P{sub 2}O{sub 7}. Experimental evidenced are advanced for non existent compounds such as: U{sub 3}(PO{sub 4}){sub 4}, U{sub 2}O{sub 3}P{sub 2}O{sub 7} and Th{sub 3} (PO{sub 4}){sub 4}. Characterization by several techniques (X-rays and neutron powder diffractions, UV-Visible and Infra-red spectroscopies, XPS,...) were performed. The ab initio structure determination of U(UO{sub 2})(PO{sub 4}){sub 2} has been achieved by X-rays and refined by neutron diffractions. Through its physico-chemical analysis, we found that this compound was a new mixed valence uranium ...

UK PubMed Central (United Kingdom)

Abs are central to malaria immunity, which is only acquired after years of exposure to Plasmodium falciparum (Pf). Despite the enormous worldwide burden of malaria,...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

In this study, the biosorption of Acid Blue 290 and Acid Blue 324 on Spirogyra rhizopus, a green algae growing on fresh water, was studied with respect to initial pH, temperature, initial dye concentration and biosorbent concentration. The optimum initial pH and temperature values for AB 290 and AB 324 biosorption were found to be 2.0, 30 deg. C and 3.0, 25 deg. C, respectively. It was observed that the adsorbed AB 290 and AB 324 amounts increased with increasing the initial dye concentration up to 1500 and 750 mg/L, respectively. The Langmuir, Freundlich, Redlich-Peterson and Koble-Corrigan isotherm models were applied to the experimental equilibrium data and the isotherm constants were determined by using Polymath 4.1 software. The monolayer coverage capacities of S. rhizopus for AB 290 and AB 324 dyes were found as 1356.6 mg/g and 367.0 mg/g, respectively. ...

International Nuclear Information System (INIS)

Tripartite efflux systems are responsible for the export of toxins across both the inner and outer membranes of Gram negative bacteria. Previous work has indicated that EmrAB-TolC from Escherichia coli is such a tripartite system, comprised of EmrB an MFS transporter, EmrA, a membrane fusion protein and TolC, an outer membrane channel. The whole complex is predicted to form a continuous channel allowing direct export from the cytoplasm to the exterior of the cell. Little is known, however, about the interactions between the individual components of this system. Reconstitution of EmrA + EmrB resulted in co-elution of the two proteins from a gel filtration column indicating formation of the EmrAB complex. Electron microscopic single particle analysis of the reconstituted EmrAB complex revealed the presence of particles approximately 240 x 140 A, likely to correspond to two EmrAB dimers in a back-to-back ...

International Nuclear Information System (INIS)

Anti-carcinoembryonic antigen monclonal antibody (MAb) CEA 102 was produced by immunization with purified CEA and the specific accumulation of radiolabeled CEA 102 in colorectal cancers was investigated by autoradiography of sugical specimens using Fuji Computed Radiography (FCR). Five patients with colorectal cancer were injected intravenously with "1"3"1I-labeled intact CEA 102 or its F(ab')_2. Primary tumor and liver metastases were successfully detected by external scanning with a gamma camera in 4 cases. Autoradiographic study of the surgical specimens using FCR showed predominant localization of "1"3"1I-labeled CEA 102 in primary tumors and liver metastases in all cases. Even a small liver metastasis (0.5 cm) was clearly visualized in the autoradiogram by FCR. The pixel distribution curves of the density of the respective tissues in the autoradiograms by FCR showed the heterogeneity of the distribution of administreted radiolabeled MAb in ...

UK PubMed Central (United Kingdom)

The multidrug efflux transporter AcrAB-TolC is known to pump out a diverse range of antibiotics, including β-lactams. However, the kinetic constants of the efflux process, needed for the quantitative...Full Text Available

British Library Electronic Table of Contents (United Kingdom)

In order to achieve efficient d-lactic acid fermentation from a mixture of xylose and glucose, the xylose-assimilating xylAB operon from Lactobacillus pentosus (PXylAB) was introduced into an l-lactate dehydrogenase gene (ldhL1)-deficient Lactobacillus plantarum (?ldhL1-xpk1::tkt-?xpk2) strain in which the phosphoketolase 1 gene (xpk1) was replaced with the transketolase gene (tkt) from Lactococcus lactis, and the phosphoketolase 2 (xpk2) gene was deleted. Two copies of xylAB introduced into the genome significantly improved the xylose fermentation ability, raising it to the same level as that of ?ldhL1-xpk1::tkt-?xpk2 harboring a xylAB operon-expressing plasmid. Using the two-copy xylAB integrated strain, successful homo-d-lactic acid production was achieved from a mixture of 25?g/l xylos...

British Library Electronic Table of Contents (United Kingdom)

Aberrant amyloid-b peptide (Ab) accumulation along with altered expression and function of nicotinic acetylcholine receptors (nAChRs) stand prominently in the etiology of Alzheimer's disease (AD). Since the discovery that Ab is bound to a7 nAChRs under many experimental settings, including post-mortem AD brain, much effort has been expended to understand the implications of this interaction in the disease milieu. This research update will review the current literature on the a7 nAChR-Ab interaction in vitro and in vivo, the functional consequences of this interaction from sub-cellular to cognitive levels, and discuss the implications these relationships might have for AD therapies.

British Library Electronic Table of Contents (United Kingdom)

Abstract Hepatitis B (HBV) and C (HCV) viruses are the most important infections transmitted by the parenteral route in patients receiving maintenance dialysis. The prevalence varies markedly from country to country. The aim of this study is to review the efficacy of the strategies to reduce the incidence of these infections and the trend of results in Iran. As a routine, all hemodialysis patients in Iran have biannual blood samples for assessment of serum HBSAg, HBS Abs, and HCV Abs. The data are collected in the Ministry of Health. For statistical analysis, prevalence, and incidence were calculated. There is an increasing prevalence/incidence of end-stage renal disease (ESRD) in Iran, from 238/49.9 pmp in 2000 to 357/63.8 pmp in 2006. The prevalence of positive HBSAg and HCV Abs decrease...

Science.gov (United States)

... QVUX`TcYWjRSZ[YXTeof\\OWXabgn]egig[Z^S]^`PhlWOe_W\\V_DKFFNZSMVT_NT[QXOMX\\\\TY] aSRd[^roan`rdt[\\] pedel\\_ YWdrR`ehUodbi`_abXUbi_O[\\i[ZSfZHX^Zkhc_T^jav ...

British Library Electronic Table of Contents (United Kingdom)

The levels of General Transcription Factor (TF) IIA were examined during mammalian brain development and in rat embryo fibroblasts and transformed cell lines. The large TFIIA subunit paralogues ab and t are largely produced in unsynchronized cell lines, yet only TFIIA ab is observed in a number of differentiated tissue extracts. Steady-state protein levels of the TFIIA t, ab, and g subunits were significantly reduced when human embryonal (ec) and hepatic carcinoma cell lines were stimulated to differentiate with either all-trans-retinoic acid (ATRA) or sodium butyrate. ATRA-treated NT2-ec cells required replating to induce a neuronal phenotype and loss of detectable TFIIA t and g proteins. High levels of TFIIA t, ab, and g and Sp factors were identified in extracts from human fetal and rat...

UK PubMed Central (United Kingdom)

Background/Objective:Three patients with spinal cord injury (SCI) and 3 able-bodied (AB) patients were infused with naloxone during a study to examine their neuroendocrine...Full Text Available

UK PubMed Central (United Kingdom)

The agglutination of human platelets by ristocetin and von Willebrand factor was inhibited by aggregated immunoglobulin (Ig)G and by Fc fragments of IgG, but not by Fab, F(ab′)₂ or...Full Text Available

Energy Technology Data Exchange (ETDEWEB)

The device is designed for automatic testing of the degree of discharge of tractive storage batteries (AB) for electric loaders, electric cars and electric ore locomotives. The basic electrical schematic of the device is cited.

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A {lambda}gt11 cDNA library was constructed from poly(U)-Spharose-selected Entamoeba histolytica trophozoite RNA in order to clone and identify surface antigens. The library was screened with rabbit polyclonal anti-E. histolytica serum. A 700-base-pair cDNA insert was isolated and the nucleotide sequence was determined. The deduced amino acid sequence of the cDNA revealed a cysteine-rich protein. DNA hybridizations showed that the gene was specific to E. histolytica since the cDNA probe reacted with DNA from four axenic strains of E. histolytica but did not react with DNA from Entamoeba invadens, Acanthamoeba castellanii, or Trichomonas vaginalis. The insert was subcloned into the expression vector pGEX-1 and the protein was expressed as a fusion with the C terminus of glutathione S-transferase. Purified fusion protein was used to generate 22 monoclonal antibodies (mAbs) and a mouse polyclonal antiserum specific for the E. histolytica portion of the fusion protein. ...

International Nuclear Information System (INIS)

The helicase action of the Escherichia coli UvrAB complex on a covalently closed circular DNA template was monitored using bacterial DNA topoisomerase I, which specifically removes negative supercoils. In the presence of E. coli DNA topoisomerase I and ATP, the UvrAB complex gradually introduced positive supercoils into the input relaxed plasmid DNA template. Positive supercoils were not produced when E. coli DNA topoisomerase I was replaced by eukaryotic DNA topoisomerase I or when both E. coli and eukaryotic DNA topoisomerases I were added simultaneously. These results suggest that like other DNA helix-tracking processes, the ATP-dependent action of the UvrAM complex on duplex DNA simultaneously generates both positive and negative supercoils, which are not constrained by protein binding but are torsionally strained. The supercoiling activity of UvrAB on UV-damaged DNA was also studied using UV-damaged plasmid DNA and a ...

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In this study, SnO{sub 2} thin films have been grown using spray pyrolysis technique on glass substrates under a substrate temperature (T{sub s} = 440 {sup o}C). The precursors were methanol CH{sub 4}O and anhydrous tin tetrachloride. XRD analyses yielded strong (1 1 0)-(1 0 1)-(2 0 0) X-ray diffraction peaks which are characteristics to tetragonal crystals. Atomic Force Microscopy (AFM) analyses showed the existence of clusters with particular pyramidal shapes. The main part of this study concerns the optical measurements of transmittance T({lambda}) and reflectance R({lambda}) spectra inside 250-1800 nm domain. Conjoint optical and thermal properties were deduced using the Amlouk-Boubaker Opto-Thermal Expansivity {psi}{sub AB}. The obtained value: {psi}{sub AB} {approx} 23.4 m{sup 3} s{sup -1} helped situating the performance of the as-grown SnO{sub 2} compound among most known PV-T oxides like ZnO and TiO{sub 2}.

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The diagnosis of dialysis-related amyloid (AB-amyloid) has been based usually on clinical and radiological criteria. Following the discovery that beta 2-microglobulin was the major protein of this amyloid, we isolated and radiolabelled uremic plasma beta 2-microglobulin. After intravenous injection, gamma-camera images of selected joint areas were obtained from 42 patients who were on regular hemodialysis therapy. Positive scans involving the shoulder, hip, knee and carpal regions were found in 13 of 14 patients treated for more than 10 years and 10 of 16 patients treated for 5 to 10 years. Patients treated for less time had negative scans. Specificity was indicated by negative scans in non-amyloid inflammatory lesions in control hemodialysis patients. Up to 48-fold tracer enrichment was detected in excised AB-amyloid containing tissue as compared to amyloid-free tissue. These findings suggest that circulating radiolabelled beta 2-microglobulin ...

Science.gov (United States)

density is slightly higher, its electrical conductivity is much higher, and it is slightly ... Sea water has characteristic properties (e.g. density) that are independent of ...

British Library Electronic Table of Contents (United Kingdom)

Summary The objective of this study was to examine the role of root carbohydrate levels and metabolism in the waterlogging tolerance of contrasting mung bean genotypes. An experiment was conducted with two cultivated mung bean (Vigna radiata) genotypes viz., T44 (tolerant) and Pusa Baisakhi (PB) (susceptible), and a wild Vigna species Vigna luteola under pot-culture to study the physiological and molecular mechanism of waterlogging tolerance. Waterlogging resulted in decrease in relative water content (RWC), membrane stability index (MSI) in root and leaf tissues, and chlorophyll (Chl) content in leaves, while the Chl a/b ratio increased. Waterlogging-induced decline in RWC, MSI, Chl and increase in Chl a/b ratio was greater in PB than V. luteola and T44. Waterlogging caused decline in tot...

British Library Electronic Table of Contents (United Kingdom)

Ethnopharmacological relevance: Tong Luo Jiu Nao (TLJN) is a modern Chinese formula based on Traditional Chinese Medicine theory that has been used to treat ischemic cerebral stroke and vascular dementia. TLJN belongs to the ethnopharmacological family of medicines. In this study, we investigated the mechanism of the TLJN effect on Alzheimer's disease (AD). Aim of the study: To investigate the effect of TLJN on b-amyloid-degrading enzymes and learning and memory in the AD rat brain. Materials and methods: AD rats whose disease was induced by Ab25-35 injection into the bilateral hippocampus CA1 region were subjected to intragastric administration of various preparations. The experimental animals were healthy male Sprague-Dawley rats which were randomly divided into normal, sham, model, TLJN...

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1. In order to carry out isothermic crystal growth experiments of YBCO the 123 primary crystallization field was determined by means of phase diagram investigations and crystal growth experiments at different oxygen partial pressure. 2. YBCO single crystals of high crystallographic perfection were grown and conclusions on the flux pinning mechanism were drawn. 3. By means of Liquid Phase Epitaxy (LPE) single crystalline (Tc{approx}90 K; {Delta}T{<=}0.5 K) c- and a,b- YBCO fils have been prepared on NdGaO{sub 3} and LaGaO{sub 3} substrates. The films were characterized structurally and magnetically. 4. Our fist melt textured YBCO ``single crystals`` possess intracrystalline critical current densities >10{sup 4} A/cm{sup 2} at B{<=}2T. The irreversibility inductions are {<=}6 T at 77 K. A simple demonstrator was constructed together with the IFW Dresden and a growth model was developed. 5. Using above all torque magnetometer ...

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No abstract prepared.

Science.gov (United States)

... 44 2. Luminance Power Spectral Density Measurements ..... 44 ... 50 4. Chrominance Power Spectral Density Measurements ..... 53 ...

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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.

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We show that the relation between D-branes and noncommutative tachyons leads very naturally to the relation between D-branes and K-theory. We also discuss some relations between D-branes and K-homology, provide a noncommutative generalization of the ABS construction, and give a simple physical interpretation of Bott periodicity. In addition, a framework for constructing Neveu--Schwarz fivebranes as noncommutative solitons is proposed.

International Nuclear Information System (INIS)

Papers presented at a meeting on indoor and outdoor climates on sites polluted with volatile organic chemicals. The papers deal with the subject of evaporation of organic chemicals on the polluted sites in relation to the influence on indoor and outdoor climates. Themes dealt with are diffusion through soils and transport of pollutants from the soil into buildings. (AB).

UK PubMed Central (United Kingdom)

In this study we show the effect of anti-sulfatide (RmAb) antibodies and inflammatory cytokines, TNF-α and IFN-γ in inducing myelin basic protein (MBP) degradation in myelin...Full Text Available

UK PubMed Central (United Kingdom)

The influence of obesity on the metabolism of apolipoprotein B (apo B) in very low density lipoprotein (VLDL), intermediate density lipoprotein (IDL), and low density lipoprotein (LDL) was investigated...Full Text Available

UK PubMed Central (United Kingdom)

Parasite transmission generally exhibits some form of positive density dependence. Thus, as population density increases, so too does the per capita risk of becoming infected. Under...Full Text Available

Science.gov (United States)

Plasma generated in low-density vapor by a negative ion beam has been studied experimentally and computationally. We show that space charge neutralization of the beam occurs at very low vapor density, and that correspondingly the electron density may be much less than the beam and plasma ion densities. When there is a large local gas density, as in a charge changing cell, the resulting high electron density is also localized to the same region. Therefore, very few electrons will reach a negative ion accelerator even if it is placed one or two beam diameters from such a cell.

CERN Document Server

Let A and B be two affinely generating sets of (Z_2)^n. As usual, we denote their Minkowski sum by A+B. How small can A+B be, given the cardinalities of A and B? We give a fairly tight answer to this question. Our bound is attained when both A and B are unions of cosets of a certain subgroup of (Z_2)^n. These cosets are arranged as Hamming balls, the smaller of which has radius 1. By similar methods, we reprove the Freiman-Ruzsa theorem in (Z_2)^n, with an optimal upper bound. Denote by F(K) the maximal spanning constant || / |A|, over all subsets A of (Z_2)^n with doubling constant |A+A| / |A| < K. We explicitly calculate F(K), and in particular show that 4^K / 4K < F(K) (1+o(1)) < 4^K / 2K. This improves the estimate F(K) = poly(K) 4^K, found recently by Green and Tao and by Konyagin.

British Library Electronic Table of Contents (United Kingdom)

Previous research utilizing the AcB/BcA recombinant congenic strains (RCS) of mice mapped provisional quantitative trait loci (QTLs) for the psychostimulant effects of nicotine to multiple regions on chromosomes 7, 11, 12, 14, 16, and 17. The current study was designed to confirm these QTLs in an A/J (A)??C57Bl/6J (B6) F2 cross and a panel of B6.A chromosome substitution strains (CSS). The panel of B6.A CSS consists of 21 strains, each carrying a different A/J chromosome on a B6 background. The A??B6 F2, CSS, A, and B6 mice were tested for sensitivity to the effects of nicotine on locomotor activity using a computerized open-field apparatus. In A??B6 F2 mice two QTLs were identified which confirm those previously observed in the AcB/BcA RCS. Significant differences in the expression of ...

International Nuclear Information System (INIS)

... californium 252 fftf reactor mockup power density reactor cores reactor noise

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Electronic structure calculations frequently invoke periodic boundary conditions to solve for electrostatic potentials. For systems that are electronically charged, or contain dipole (or higher) moments, this artifice introduces spurious potentials due to the interactions between the system and multipole moments of its periodic images in aperiodic directions. I describe a method to properly handle the multipole moments of the electron density in electronic structure calculations using periodic boundary conditions. The density for which an electrostatic potential is to be evaluated is divided into two pieces. A local density is constructed that matches the desired moments of the full density, and its potential computed treating this density as isolated. With the density of this local moment countercharge removed from the full density, the ...

Science.gov (United States)

... Compilation Part Notice ADP023645 TITLE: Filtered Density Function for Subgrid Scale Modeling of Turbulent Diffusion Flames ...

Science.gov (United States)

FIG. 4. Power Spectral Density of the MAP W11 radiometer. The red and black traces are the power spectral density measurements of the two detectors on the ...

Science.gov (United States)

t5I gU9S y`xmRv A'b9 (RW$ F]>H ?ts6@ Snnl yHl$- #|t_C 6G8@ u,H8 3($ds #~^iy { aN2s VFR@1 zs|9n] %pyNv Z{+; !C 1cs= ||8_ 6r$0j n9X 8n`@ ,FH8S hg3` TBq*p UP09 ...

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Partial oxidation of 2-propanol was carried out on AB{sub 1-x}B`{sub x}O{sub 3} (A=Ba, B=Pb, Ce, Ti; B`=Bi, Sb and Cu) type perovskite oxides. Acetone was the major product observed on all the catalysts. All the catalysts underwent partial reduction during the reaction depending on the composition of the reactant, nature of the B site cation and the extent of substitution at B site. The catalytic activity has been correlated with the reducibility of the perovskite oxides determined from Temperature Programmed Reduction (TPR) studies. (orig.)

CERN Document Server

We review an analysis of a consistent renormalization of the top and bottom quark/squark sector of the MSSM with complex parameters (cMSSM). Various renormalization schemes are defined, analyzed analytically and tested numerically in the decays Stop_2 -> Sbottom_i H^+/W^+ (i = 1,2). No scheme is found that produces numerically acceptable results over all the cMSSM parameter space, where problems occur mostly already for real parameters. Some numerical examples for Gamma(Stop_2 -> Sbottom_1 H^+) in our preferred scheme, "m_b, A_b DRbar" are shown.

CERN Document Server

In this note, we derive from Anstee's fractional $(g,f)$-factor theorem a similar characterization for the property of all fractional $(g,f)$-factors. Let $a$ be two positive integers and $G$ a graph of order $n$ sufficiently large for $a$ and $b$. Then G has all fractional $[a, b]$-factors if the minimum degree is at least $\\delta(G)\\geq \\frac{1}{4a}((a+b-1)^2+4b)$ and every pair of non-adjacent vertices has cardinality of the neighborhood union at least $bn/(a + b)$. This lower bounds are sharp.

Science.gov (United States)

... Title : THE INFLUENCE OF GRAIN BOUNDARY CARBIDE DENSITY ON THE BRITTLE FRACTURE OF FERRITE PEARLITE STEELS. ...

Science.gov (United States)

... Descriptors : *PROPELLING CHARGES, *NITROCELLULOSE, *COMBUSTIBLE CARTRIDGE CASES, DENSITY, FIBERS, MANUFACTURING ...

Energy Technology Data Exchange (ETDEWEB)

This work shows the influence of the consumer density (density/km) in rural electric networks implementation costs. The analysis of the costs aims the criteria definition for the calculation of the financial involving rates of the rural consumer density. 3 figs., 10 tabs.

International Nuclear Information System (INIS)

By the methods of small-angle X-ray scattering and translucent electron microscopy the existence of inhomogeneity of electron density in hydrogenated films of amorphous silicon is confirmed. The decreased density regions are extended and form a branched network of channels oriented mostly by the normal direction to the films surface. The typical size of the decreased density regions network constitutes 10 nm in the 100-800 nm films thickness range. The increase of hydrogen total partial pressure in gas mixture in case of films growth results at first in the decrease of extension of these regions and than to micropores generation in the network nodal points of the decreased electron density regions.

International Nuclear Information System (INIS)

The possibilities, advantages, and difficulties of determining nuclear matter densities by elastic scattering of alpha-particles are generally discussed. On the basis of particular experimental data - 104 MeV alpha-particle scattering from "4"0,"4"2,"4"4,"4"8Ca - a refined folded potential is introduced using a density-dependent alpha-nucleon-interaction and target nucleus densities described by Fourier-Bessel-series. Thereby, the total nucleon densities of these isotopes were determined with little model dependence. The resulting root-mean-square radii and density differences are compared with other experimental results obtained by different methods. (orig.).

Energy Technology Data Exchange (ETDEWEB)

Pd/sub 2/Si formation at the Pd-Si interface induced by irradiation with ions having a wide range of nuclear energy of deposition density has been investigated. It is found that the thickness of the silicide layer formed by irradiation is proportional to the ion fluence for irradiation with ions having low energy-deposition densities, while it is proportional to the square root of the fluence for irradiation with ions having energy-deposition densities. The results indicate that Pd/sub 2/Si formation is reaction limited when the energy-deposition density at the interface is low and is diffusion limited when it is high. The results are compared with the phenomenological theory developed by Horino et al. and it is shown that such a dependence of the limiting processes on the energy depositon density is induced when the diffusion is thermally activated while the reaction at the ...

Science.gov (United States)

We describe the Hubble Space Telescope (HST) Wide Field Camera 3 (WFC3) Early Release Science (ERS) observations in the GOODS-South field. The new WFC3 ERS data provide calibrated, drizzled mosaics with FHWM=0.07--0.15" in the near-UV (filters F225W, F275W, and F336W) and near-IR (F098W, F125W, and F160W) in typically 2 orbits per filter. Together with the existing HST/ACS GOODS-S mosaics in the BVi'z' filters, the 10-band ERS data cover 40-50 sq. arcmin to AB=26-27.0 mag (10-sigma for point sources). In this poster, we describe the: (1) scientific rationale, data taking and reduction procedures of the WFC3 ERS mosaics; (2) object cataloging and star-galaxy separation techniques used in these 10 different filters; (3) reliability and completeness of the 10-band object catalogs from the ERS mosaics; (4) object counts in 10 different filters from 0.2-1.7 microns to AB=26.0-27.0 mag; and (5) the full-color 10-band ERS images. We discuss the ...

British Library Electronic Table of Contents (United Kingdom)

Tungsten, in the form of tungstate, polymerizes with phosphate, and as extensive polymerization occurs, cellular phosphorylation and dephosphorylation reactions may be disrupted, resulting in negative effects on cellular functions. A series of studies were conducted to evaluate the effect of tungsten on several phosphate-dependent intracellular functions, including energy cycling (ATP), regulation of enzyme activity (cytosolic protein tyrosine kinase [cytPTK] and tyrosine phosphatase), and intracellular secondary messengers (cyclic adenosine monophosphate [cAMP]). Rat noncancerous hepatocyte (Clone-9), rat cancerous hepatocyte (H4IIE), and human cancerous hepatocyte (HepG2) cells were exposed to 1-1000 mg/l tungsten (in the form of sodium tungstate) for 24 h, lysed, and analyzed for the ab...

Energy Technology Data Exchange (ETDEWEB)

The human articular cartilagineous proteoglycans (PG) R.I.A. is highly specific. The PG used as the standard and the /sup 125/I labelled molecule appear to be pure. Under these conditions, all the potential interfering substances which have been tested show no cross reaction. For instance, the Ag-Ab equilibrium is not affected by adding human IgG, human albumin, hyaluronic acid, chondroitin sulfate, rat type II collagen or total human serum proteins. This R.I.A. also exhibits a species spcificity since there is no cross reaction with rat PG and negligible cross section with dog PG. The results obtained after addition of enzymes to the antigen demonstrate that the antigenic sites are localized on the protein region and not on the glycosaminoglycan region of the molecule.

Energy Technology Data Exchange (ETDEWEB)

A survey was undertaken of literature on the conversion of coke-fired cupola furnaces so that they can be fuelled, either wholly or partially, with natural gas. The aim was to determine the most suitable method for a specific furnace. Substitution with natural gas can result in speedier adjustment and control of the smelting process and in addition operational costs are reduced as natural gas is a cheaper fuel. The payback period would be one year. Pollutive emissions would be reduced. It was concluded that the most satisfactory solution would be that 3-4 gas burners should be placed immediately above the smelting zone in the furnace. Each burner should be placed in a separate combustion box in which the complete combustion process could take place. The burners should be placed symmetrically about the furnace, pointing at a small degree downwards. In this way the combustion chamber will not be filled with materials from the furnace and the burners will not be damaged. ...

British Library Electronic Table of Contents (United Kingdom)

A new chemical reactor, the Open Plate Reactor, is being developed by Alfa Laval AB. It combines good mixing with high heat transfer capacity into one operation. With the new concept, highly exothermic reactions can be produced using more concentrated reactants. A nonlinear model of the reactor is derived and a control system is developed. For temperature control a cooling system is designed and experimentally verified, which uses a mid-ranging control structure to increase the operating range of the hydraulic equipment. A Model Predictive Controller is proposed to maximize the conversion under hard input and state constraints. An extended Kalman filter is designed to estimate unmeasured concentrations and parameters. Simulations show that the designed control system gives high conversion ...

Energy Technology Data Exchange (ETDEWEB)

ABB High Voltage Cables AB started the MPS (More Power Submarine cables) project in 1993 with a view to exploring new technology opportunities. The goal is to design and type test a submarine HVDC cable for a capacity of 1200 MW at 600 kV. On the day before ABB announced its success in winning the contract for the world`s largest ever submarine HVDC link project for the gigantic Bakun project in Malaysia, ABB Power Systems described progress to date at a symposium in Karlskrona. The proceedings included a test demonstration on an extruded cable which eventually broke down at a stress of over 935 kV -not in the insulation itself but in the end terminations. The electric field was in excess of 200 kV/mm which is higher than ever before reported. (UK)

British Library Electronic Table of Contents (United Kingdom)

2-methylpropan-1-ol (isobutanol) is a leading candidate biofuel for the replacement or supplementation of current fossil fuels. Recent work has demonstrated glucose to isobutanol conversion through a modified amino acid pathway in a recombinant organism. Although anaerobic conditions are required for an economically competitive process, only aerobic isobutanol production has been feasible due to an imbalance in cofactor utilization. Two of the pathway enzymes, ketol-acid reductoisomerase and alcohol dehydrogenase, require nicotinamide dinucleotide phosphate (NADPH); glycolysis, however, produces only nicotinamide dinucleotide (NADH). Here, we compare two solutions to this imbalance problem: (1) over-expression of pyridine nucleotide transhydrogenase PntAB and (2) construction of an NADH-de...

Energy Technology Data Exchange (ETDEWEB)

The overall aim is to develope programme modules for a Danish integrated computer system for projecting buildings and to ensure that Danish programmes are compatible with international systems. The programmes to be integrated here were AutoCAD and SCRIBE-Models and the simulation programme tsbi3 for the calculation of indoor climate conditions, power demand and energy consumption in buildings. For the calculation of humidity and temperature conditions in constructions a certain amount of integration is carried out with the MATCH programme (Moisture And Temperature calculations for Constructions of Hygroscopic materials). The activities embodied in the pilot projects are described in this working report in addition to individual computer programmes and prototypes, and examples and diagrams are presented. The programmes described deal with handling design elements in relation to AutoCAD designs, and the formatting of a building`s data from AutoCAD to tsbi3 format. ...

Science.gov (United States)

Phase II Randomized Study of the Effect of Zoledronate Versus Observation on Bone Mineral Density of the Lumbar Spine in Patients Undergoing Risk-Reducing Excision of Both Ovaries (GOG-0215). See the protocol summary.

UK PubMed Central (United Kingdom)

We use high-density single nucleotide polymorphism (SNP) genotyping microarrays to demonstrate the ability to accurately and robustly determine whether individuals are in a complex genomic DNA mixture....Full Text Available

Energy Technology Data Exchange (ETDEWEB)

Effects associated with the temperature dependence of the level density parameter, a(T), are investigated in connection with neutron evaporation processes. Different approximations, for this temperature dependence, are compared for the case of neutron emission from the compound nucleus /sup 209/Pb.

Science.gov (United States)

Sep 1, 2011 ... Title: Hardness, density, and shrinkage characteristics of silk-oak from Hawaii. Author: Youngs, R. L.. Date: 1964. Source: Research note FPL ...

UK PubMed Central (United Kingdom)

Phonological density refers to the number of words that can be generated by replacing a phoneme in a target word with another phoneme in the same position. Although the precise nature of the...Full Text Available

UK PubMed Central (United Kingdom)

Objectives To assess the effectiveness of calcium supplementation for improving bone mineral density in healthy children and to determine if any effect is modified by other factors and...Full Text Available

UK PubMed Central (United Kingdom)

Various physico-chemical tissue optical clearing (TOC) methods have been suggested to maximize photon density in tissue. In order to enhance photon density, a compression-controlled low-level...Full Text Available

UK PubMed Central (United Kingdom)

In the growing chloronema cell suspension cultures of the moss Funaria hygrometrica Hedw., activities of several enzymes have been found to be cell-density-dependent. Cyclic nucleotide...Full Text Available

UK PubMed Central (United Kingdom)

BackgroundLymph node metastasis in endometrial cancer significantly decreases survival rate. Few data on the influence of intratumoral lymphatic microvessel density (LMVD) on survival...Full Text Available

Science.gov (United States)

... Measuring Instruments ..... 7-18 7.4 Power Spectral Density Measurements of Random DaL. .... 7-19 7 ...

International Nuclear Information System (INIS)

Excitation of the HF electric field in the local plasma resonance region (LPRR) of inhomogeneous plasma by pumping electric field or modulated electron beam results to appearance of the ponderomotive force that presses plasma out of this region. Density cavity is formed in the LPRR due to this field. Further dynamics in this region depends on the plasma properties. For plasma with hot electrons ion-acoustic pulses run away from the cavity. at the local density maximum the new peak of electric field is excited. It results to the formation of new density cavity, etc. For isothermal plasma the density jump is formed.

Energy Technology Data Exchange (ETDEWEB)

Techniques for studying nuclear structure are reviewed. Examples are given of charge density determinations by electron and proton inelastic scattering. (AIP)

CERN Document Server

Full-Potential Electronic Structure Method

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

International Nuclear Information System (INIS)

... actinides comparative evaluations deformed nuclei even-even nuclei governor

Energy Technology Data Exchange (ETDEWEB)

Electron scattering data have been used to obtain transition charge densities for the low-lying E2 transitions in /sup 88/Sr, /sup 89/Y, and /sup 90/Zr. These charge densities show a characteristic shape indicative of their microscopic constituency, modified by core-polarization effects. A good description of transitions in the even-even nuclei is obtained by using the measured single-particle transitions in /sup 89/Y as effective densities. .ID LV2086 .PG 19 22

Science.gov (United States)

... measurement. Power spectral density measurements are made by the dynamic signal analyzer for each channel. A cross power ...

Energy Technology Data Exchange (ETDEWEB)

It is noted that the existence of cosmic-ray semidiurnal anisotropy of interplanetary origin has generally been attributed to the symmetrically rising density gradients perpendicular to the solar equatorial plane. An increase in the magnitude of the semidiurnal anisotropy of cosmic rays during the years 1973-1975 by a factor of 2 is in theory expected to be associated with larger magnitudes of the heliolatitudinal density gradients. The distribution of cosmic-ray intensity in the heliolatitude range + or - 7.25 deg obtained using the data of the Deep River neutron monitor is shown not to support the density gradient hypothesis. The presence of symmetrical gradients at higher heliolatitudes, however, cannot be ruled out.

Energy Technology Data Exchange (ETDEWEB)

No abstract prepared.

UK PubMed Central (United Kingdom)

In this study, bone mineral density (BMD) of normal (CON), ovariectomized (OVX) and partially nephrectomized (NFR) rats was measured by ³¹P NMR spectroscopy; bone matrix density was...Full Text Available

International Nuclear Information System (INIS)

The effect of two-body nature of the nuclear shell model potential on the recent numerical calculations of the nuclear level density has been examined. For the two most widely used single particle energy level schemes based on harmonic oscillator and Woods-Saxon potential, this effect is shown to significantly modify the excitation energy dependence of the level densities. (author).

Energy Technology Data Exchange (ETDEWEB)

Separate entries were made in the data base for 17 of the 19 papers included. Two papers were previously included in the data base. Workshop reports are included on (1) nuclear level density theories and nuclear model reaction cross-section calculations and (2) extraction of nuclear level density information from experimental data. (WHK)

International Nuclear Information System (INIS)

Dynamical models are presented that start with interstellar gas in an initial diffuse state and consider their gravitational collapse and the formation of dense cores. Frozen-in tangled magnetic fields are included to mimic forces that might oppose gravitational contraction and whose effectiveness may increase with increasing core densities. Results suggest the possibility that dense cloud cores may be dynamically evolving ephemeral objects, such that their lifespan at a given core density decreases as that density increases. 66 refs.

Energy Technology Data Exchange (ETDEWEB)

A general expression for the current-density distribution of a focused-ion beam (FIB) in the chromatic-aberration region is set up in the form of a definite integral. With the experimentally obtained ion-energy distribution of a liquid-metal ion source, its contribution to the FIB current-density distribution is estimated. Calculated results explain the wide-exponential tail of a FIB.

CERN Document Server

A consistent combination of quantum geometry effects rules out a large class of models of loop quantum cosmology and their critical densities as they have been used in the recent literature. In particular, the critical density at which an isotropic universe filled with a free, massless scalar field would bounce must be well below the Planck density. In the presence of anisotropy, no model of the Schwarzschild black hole interior analyzed so far is consistent.

Energy Technology Data Exchange (ETDEWEB)

Radioisotopes of Pb(II) have been of some interest in radioimmunotherapy and radioimmunoimaging (RII). However, the absence of a kinetically stable bifunctional chelating agent for Pb(II) has hampered its use for these applications. {sup 203}Pb (T{sub 1/2}=52.02 h) has application potential in RII, with a {gamma}-emission that is ideal for single photon emission computerized tomography, whereas {sup 212}Pb (T{sub 1/2}=10 h) is a source of highly cytotoxic {alpha}-particles via its decay to its {sup 212}Bi (T{sub 1/2}=60 min) daughter. The synthesis of the novel bifunctional chelating agent 2-(4-isothiocyanotobenzyl)-1,4,7,10-tetraaza-1,4,7,10-tetra-(2-carbamoyl methyl)-cyclododecane (4-NCS-Bz-TCMC) is reported herein. The Pb[TCMC]{sup 2+} complex was less labile to metal ion release than Pb[DOTA]{sup 2-} at pH 3.5 and below in isotopic exchange experiments. In addition to increased stability to Pb{sup 2+} ion release at low pH, the bifunctional TCMC ligand was found to have many other ...

International Nuclear Information System (INIS)

Adduct formation between U(TTA)_4 and several neutral donor (S) was investigated by utilizing the changes in the absorption spectra of U(IV) resulting from the addition of neutral donors to a solution of U(TTA)_4. All the donors used in the present work from 1:1 adducts with U(TTA)_4. From the spectral changes, the equilibrium constants #beta#sub(AB) for the adduct formation reaction viz U(TTA)_4 S reversible U(TTA)_4.S were calculated for a few neutral donors. The log #beta#sub(AB) values obtained in benzene medium, are :TOPO (6.23), TBPO (6.13), TPPO (4.72), DBBP(4.04) TBP(3.04), TIOTP(1.27) and MIBK(-0.10) and a value of 3.98 for TOPO in chloroform medium. The adduct formation was found to result in increasing the coordination number of U(IV) from 8 in U(TTA)_4 to 9 in the adducts it forms with the neutral donors. Similar absorption spectral studies with U(DBM)_4 revealed that it forms much weaker adducts than the corresponding ones with ...

Science.gov (United States)

In 1999, RECONS (Research Consortium on Nearby Stars) began gathering astrometric data using the CTIO 0.9m under the auspices of the NOAO Surveys Program. In 2003, SMARTS began operating the 0.9m and the program continued, with an enhanced ability to acquire long-term astrometric series on the nearest stars. With over a decade of milli-arcsecond astrometry for hundreds of red dwarfs within 25 pc, we now have a rich dataset in which to search for previously unknown stellar, substellar, and planetary companions. We can also use our data to better constrain the orbits of known binaries to reduce their mass errors to less than a few percent, and consequently test astrophysical models as never before. Here we present our orbit fitting analysis of M dwarfs that show clear evidence of gravitational perturbations due to unseen companions, after solving for their proper motion and parallax signals. We show discoveries such as LHS 3738AB, found for the first time to have a ...

International Nuclear Information System (INIS)

The energy-versus-volume curve of the spin-density wave (SDW) in body-centred-cubic Cr is calculated with the density functional theory/full-potential linearized augmented plane wave (DFT/FLAPW) method using the generalized gradient approximation (GGA). The predicted ground state is not the SDW, in contrast to an earlier FLAPW calculation. A conjecture is formulated that the widely varying results of the local density approximation (LDA) and GGA - and of different solution methods - can be scaled by the size of the calculated moment. As a consequence, experimentally relevant properties of the SDW can be calculated by tuning the moment. The implications of these results for the ability of DFT to describe Cr are discussed. (author)

International Nuclear Information System (INIS)

Published density profiles and central velocity dispersions place important constraints on the stellar velocity ellipsoid and on the distribution of dark matter (DM) in the dwarf spheroidal galaxies Draco and Ursa Minor. Central velocity dispersions of 9 km/s are adopted for Draco and 11 km/s for Ursa Minor. Then, for an isotropic stellar velocity distribution, the central DM densities are 0.8 and 1.0 solar mass/cu pc, respectively, if visible and dark matter have the same core radius. If DM has a much larger core radius than visible matter but nevertheless dominates the potential, these densities are reduced by a factor of 2. Central DM densities can be lower than this only if the stellar velocity distribution is anisotropic. Simple two-component King models are used to investigate this and to look for the smallest DM densities that are consistent with the observations. 36 refs.

British Library Electronic Table of Contents (United Kingdom)

Abstract The distribution and abundance of native ungulates were measured on commercially managed, semi arid rangeland in central Kenya over a 3 year period that encompassed severe drought and above average rainfall. Native ungulate biomass density averaged 5282 kg km 2 over the study and was dominated by elephant (Loxodonta africana), impala (Aepyceros melampus) and dik dik (Madoqua kirkii). Biomass density of domestic cattle (Bos taurus) averaged 2280 kg km 2 during the study. Responses of native ungulates to severe drought were variable. Impala densities were similar to or greater than densities for similar habitat in protected areas, and varied from 12 to 16 km 2 during and following the drought to 24 29 km 2 following above average rainfall. Dik dik densities were also greater than de...

Energy Technology Data Exchange (ETDEWEB)

Changes in mass density of amorphous Pd{sub 80}Si{sub 20} were monitored in situ during irradiation with He{sup 2+} and H{sup +} ions at temperatures below 100 K and during subsequent thermal treatment. The mass density decreased with increasing ion fluence and exponentially approached a saturation value of -1.2%, corresponding to a recombination volume of 190 atomic volumes. The initial swelling rate was 2.3 atomic volumes/displaced atom. The mass density of the irradiated material increased during subsequent thermal treatment, and the irradiation-induced decrease of the mass density recovered completely at room temperature.

Energy Technology Data Exchange (ETDEWEB)

(Boiling site densities and heat-transfer coefficients have been measured for ethanol-water and ethanol-benzene mixtures at 1.01 bar for a heated vertical brass disk. A strong effect of composition on the boiling site density was observed, which was attributed to the nature of the activation of the boiling surface and mass diffusion effects. The boiling heat-transfer coefficient was found to decrease with increasin subcooling, but for the mixtures at a given level of subcooling the decrease was less than that for the single components and azeotropic mixtures.) The heat-transfer coefficient at a given heat flux was seen to be quite insensitive to the very large increase in boiling site density in comparing the pure water and the ethanol-water azeotrope results, leading one to question pool boiling models that predict heat-transfer rates on the basis of boiling site density.

International Nuclear Information System (INIS)

In the convolution/superposition method of photon beam dose calculations, inhomogeneities are usually handled by using some form of scaling involving the relative electron densities of the inhomogeneities. In this paper the accuracy of density scaling as applied to primary electrons generated in photon interactions is examined. Monte Carlo calculations are compared with density scaling calculations for air and cork slab inhomogeneities. For individual primary photon kernels as well as for photon interactions restricted to a thin layer, the results can differ significantly, by up to 50%, between the two calculations. However, for realistic photon beams where interactions occur throughout the whole irradiated volume, the discrepancies are much less severe. The discrepancies for the kernel calculation are attributed to the scattering characteristics of the electrons and the consequent oversimplified modeling used in the ...

Energy Technology Data Exchange (ETDEWEB)

Mass density of a composite is generally taken as the volume-averaged value of components' densities. Moreover, the same volume-averaged mass density is usually used to calculate the wave speed in the long-wavelength limit, i.e., where the wavelength is much larger than the size of the inhomogeneities. In this paper, we show via rigorous derivation that the dynamic mass density used in the calculation of (long-wavelength) wave speed can differ significantly from the static volume-averaged value. This recognition is shown to yield an excellent account of some recent experimental data, as well as to make possible the realization of acoustic metamaterials. Physical reason for the difference between two mass densities is attributed to the relative motion between the components. That is, the implicit assumption-that all components in a composite must move uniformly in the ...

Energy Technology Data Exchange (ETDEWEB)

Diagnostic capability of Fuji Computed Radiography (FCR) of the chest was compared to the conventional radiography (CoR) using regular film-screen system. FCR utilizers imaging plates of scanning laser stimulated luminescence. Visibility of 14 structures of the chest radiography was evaluated by 3 radiologists in 100 pairs of FCR and CoR which were taken at the same time with the same exposure factors. FCR was superior to CoR especially in observation of the mediastinum and areas behind the heart and diaphragm. The minor fissure was better seen on CoR. Superiority of FCR to CoR was thought to be mainly due to the processed image of FCR, and the so-called normal image of FCR had little diagnostic advantage. Simulated abnormal densities: nodular, alveolar, and interstitial densities with a chest phantom, were made, and detectability of alteration of these densities on FCR and CoR was evaluated by 19 radiologists, using ROC ...

Science.gov (United States)

In this paper we consider the adsorption of argon on the surface of graphitized thermal carbon black and in slit pores at temperatures ranging from subcritical to supercritical conditions by the method of grand canonical Monte Carlo simulation. Attention is paid to the variation of the adsorbed density when the temperature crosses the critical point. The behavior of the adsorbed density versus pressure (bulk density) shows interesting behavior at temperatures in the vicinity of and those above the critical point and also at extremely high pressures. Isotherms at temperatures greater than the critical temperature exhibit a clear maximum, and near the critical temperature this maximum is a very sharp spike. Under the supercritical conditions and very high pressure the excess of adsorbed density decreases towards zero value for a graphite surface, while for slit pores negative excess ...

International Nuclear Information System (INIS)

The 1.04 GeV-proton elastic scattering from "4"0Ca is studied in the framework of the coherent density fluctuation model (CDFM). The calculations are carried out in the Glauber theoretical scheme with three different charge densities. It is shown that: i) the account of the flucton correlations leads to results considerably different from those obtained in the independent particle Glauber approach (IPGA); ii) in contrast to the case of IPGA the use of a more realistic density improves the agreement of CDPM-results with the experimental data. (orig.).

International Nuclear Information System (INIS)

Reflection coefficients of electromagnetic waves in a nonuniform plasma layer with electrons, positive ions and negative ions, covering a metal surface are investigated by using the finite-difference-time-domain method. It is shown that the reflection coefficients are influenced greatly by the density gradient on the layer edge, layer thickness and electron proportion, i.e., the effect of the negative ions. It is also found that low reflection or high attenuation can be reached by properly choosing high electron proportion, thick plasma layer, and smooth density gradient in the low frequency regime, but sharp density gradient in the high frequency regime. (authors)

International Nuclear Information System (INIS)

An advanced video system has been assembled from commercially available equipment to support the real-time neutron radiography facility established jointly by the University of Virginia Department of Nuclear Engineering and Engineering Physics, and the Philip Morris Research Center. A schematic diagram of the equipment used for real-time neutron radiography is presented. To obtain quantitative density measurements with this system, several modifications of both hardware and image processing software were required. After implementation of these changes, the system was capable of determining material densities by measuring the degree of neutron attenuation.

Energy Technology Data Exchange (ETDEWEB)

A low power polychromatic beam of microwaves is used to diagnose the behavior of turbulent fluctuations in the core of the JT-60U tokamak during the evolution of the internal transport barrier. A continuous reduction in the size of turbulent structures is observed concomitant with the reduction of the density scale length during the evolution of the internal transport barrier. The density correlation length decreases to the order of the ion gyroradius, in contrast to the much longer scale lengths observed earlier in the discharge, while the density fluctuation level remain similar to the level before transport barrier formation.

International Nuclear Information System (INIS)

Based on the single-particle levels given by Nilsson, the intrinsic and effective (with collective effects) level density parameters as a function of the excitation energy for the "1"8"6Os, "1'8"7Ir, "1"8"9Os and "1"9"3Au deformation nuclei have been calculated in the range of the excitation energy up to 150 MeV. The calculated fission probabilities P_f (U) are consistent satisfactorily with the experimental data when a nonadiabatic estimation of the collective effects was used to calculated the nuclear level density parameters.

Energy Technology Data Exchange (ETDEWEB)

In the early 1970s Yang and Menichelli demonstrated that direct laser illumination of low-density secondary explosive prr:ssings through a transparent window could produce detonation. 'The energy requirement for threshold initiation of detonation was reduced when a thin metal coating of metal covered the side of the window against which the low-density explosive was pressed. We have obtained experimental results that are in general agreement with the results of Renllund, Stanton and Trott (1 989) and recent: work by Nagayama, hou and Nakahara (2001). We report exploration of the effects of laser beam diameter, PEiTN density and specific surface area, and thickness of a titanium coating on the window.

Energy Technology Data Exchange (ETDEWEB)

Density oscillations induced by MHD activities were observed in NBI heated plasmas on CHS by using an HCN laser interferometer. The accompanied changes of the density profiles were also observed. The oscillations are composition of m=0 sawteeth like crash and m=2 sinusoidal oscillations as a post courser of the crash. Possible models of the oscillation structure are examined in order to explain experimental data of the interferometer. Rotating plasma core, which is hollow profile and keeps constant elongation of the flux surface can explain amplitude and phase distribution of the sinusoidal oscillation. (author)

Energy Technology Data Exchange (ETDEWEB)

We show that specially designed two-dimensional arrangements of full elastic cylinders embedded in a nonviscous fluid or gas define (in the homogenization limit) a new class of acoustic metamaterials characterized by a dynamical effective mass density that is anisotropic. Here, analytic expressions for the dynamical mass density and the effective sound velocity tensors are derived in the long wavelength limit. Both show an explicit dependence on the lattice filling fraction, the elastic properties of cylinders relative to the background, their positions in the unit cell, and their multiple scattering interactions. Several examples of these metamaterials are reported and discussed.

International Nuclear Information System (INIS)

Since the 1970s, Danish electricity supply has been dependent on imported coal. This has lead to greater reliability of supply, as could be seen during the Gulf War when Danish electricity prices remained stable in contrast to conditions in other countries. The disadvantage is the air pollution caused by coal combustion. This is regulated, it is stated, by several international laws and agreements, and these are named here. The nature of this form of pollution is explained in relation to actual Danish power plants and their efforts to reduce emissions of sulphur dioxide and nitrogen oxides. Carbon dioxide, which is a greenhouse gas, is also emitted. Danish environmental policy concentrates on these problems. The efforts of the electric power companies to reduce air pollution are detailed, both nationally and internationally, and their positive consequences are described. Desulphurization and denitrification costs are claimed to be 4.6 Danish oere and 1.9 Danish oere per year per kWh ...

CERN Document Server

The influence of extended convective mixing (overshoot) on asymptotic giant branch stellar evolution is investigated in detail. The extended mixing is treated time-dependently, and the efficiency declines exponentially with the geometric distance from the convective boundary. It has been considered at all convective boundaries, including the He-flash convection zone in the intershell region which forms during the thermal pulses. Both the structural and the chemical evolution are affected by the inclusion of overshoot. The main results include a very efficient third dredge-up which leads to the formation of carbon stars of low mass and luminosity. A C13 pocket which may serve as a neutron source for the s-process can form after the third dredge-up has reached into the C12 rich intershell. Overshoot applied to the pulse-driven convective zone during the He-flash leads to a deeper penetration of the bottom of this convective zone into the C/O core below the He-burning shell. This in turn ...

Energy Technology Data Exchange (ETDEWEB)

Vaarst Vestervang (Denmark) comprises 16 villas and 1 communal building. The complex was designed by the inhabitants themselves with the aim of polluting the environment as little as possible. The land area constitutes 69.000 square meters where it is possible to grass animals. The document reports a measuring programme concerning the overall heat consumption as one of the main aims of the inhabitants is to save energy and thus contribute to the protection of the environment. The capacity of the solar collectors predominantly used in the building complex was 235 kWh/m{sup 2}. Supplementary heating is provided by boilers fired with wood. The measuring system is described in detail. Tables show the influence of heat transmission losses, ventilation, airing out of rooms, the angle of the sun`s rays within the buildings and heating needs on energy consumption. Energy consumption data is presented in relation to the forms of space and water heating utilized. Daily measurements were also ...

Energy Technology Data Exchange (ETDEWEB)

A century of technical development put steam turbines on a high level regarding efficiency and reliability. This procedure is still ongoing. The technological-commercial point of view - influenced intensively by liberalisation of the energy-market - makes great demands on field services. Well suited concepts in service and modernization are the solutions, as shown in NPP Emsland upgrade. [German] Ein Jahrhundert technischer Entwick lung brachte Dampfturbinen auf ein hohes Niveau bezueglich Effizienz und Zuverlaessigkeit. Dieser Vorgang ist auch in der heutigen Zeit nicht ab geschlossen. Die technologisch-wirtschaftliche Betrachtungs weise '' von der Liberalisierung des Strommarktes intensiv beeinflusst '' stellt dementsprechend hohe Anforderungen auch an den Kraftwerksservice. Massgeschneiderte Modernisierungs- und Servicekonzepte sind die Antwort, wie das Beispiel Kernkraftwerk Emsland zeigt. (orig.)

International Nuclear Information System (INIS)

To define the prognostic factors after surgical resection and evaluate the effectiveness of Post Operative Radiotherapy (PORT) in cases with cholangiocarcinoma, 44 cases with proximal cholangiocarcinoma were examined. The mean observation period was 20.6 months, and the survival rates 1, 3 and 5 years after the resection were 79.9%, 59.8% and 39.3%, respectively. Univariate analysis revealed that the presence of lymph node metastasis and absence of PORT were significant poor prognostic factors. Multivariate analysis revealed that the absence of PORT was a significant poor prognostic factor. The survival rates for 1 and 3 years after the resection were 80.0% and 40.0% in the curable A/B and PORT (-) group, and 100% and 53.3% in curable C and PORT (+) group. There were no local reccurences in the pathologically classified hm2 and em2 patients who underwent PORT. Even when the surgical margin is positive for the carcinoma pathologically, it is possible to avoid local ...

CERN Document Server

Context. The I(15.01 A)/I(16.78 A) emission line intensity ratio in Fe XVII has been reported to deviate from its theoretical value in solar and stellar X-ray spectra. This is attributed to opacity in the 15.01 A line, leading to a reduction in its intensity, and was interpreted in terms of a geometry in which the emitters and absorbers are spatially distinct. Aims. We study the I(15.01 A)/I(16.78 A) intensity ratio for the active cool dwarf EV Lac, in both flare and quiescent spectra. Methods. The observations were obtained with the Reflection Grating Spectrometer on the XMM-Newton satellite. The emission measure distribution versus temperature reconstruction technique is used for our analysis. Results. We find that the 15.01 A line exhibits a significant enhancement in intensity over the optically thin value. To our knowledge, this is the first time that such an enhancement has been detected on such a sound statistical basis. We interpret this enhancement in terms of a geometry in ...

British Library Electronic Table of Contents (United Kingdom)

Abstract Background & aims: Hepatitis B or C virus infection is considered to be the main cause of hepatocellular carcinoma (HCC) in Japan. Aflatoxin B1 (AFB1) is a carcinogen associated with HCC in regions with high exposure. Mutations in codon 249, exon 7 are a hallmark of AFB1 exposure. Therefore, to clarify the role of AFB1 in hepatocarcinogenesis, we examined AFB1-DNA in liver tissue and sequenced TP53 in Japanese patients with HCC. Methods: Hepatocyte AFB1-DNA adducts were determined immunohistochemically and direct sequencing of TP53 was done to determine mutations in 188 of 279 patients who underwent hepatic resection for HCC. We assessed hepatitis C virus antibodies (HCV Ab) and HBSAg expression; patients without either were defined as having non-B non-C hepatocellular carcinoma (...

Energy Technology Data Exchange (ETDEWEB)

Light increased the rate of LHCP synthesis as measured by pulse-labeling with /sup 35/SO/sub 4/ and immunoprecipitation with antibody specific for Euglena LHCP. In addition to the mature LHCP, 26,000 daltons, the LHCP specific antibody immunoprecipitated large amounts of several proteins having molecular weights of approximately 100,000. On immunoblots of immunoprecipitated unlabeled protein, the antibody only detected the mature LHCP suggesting that the high molecular weight proteins are not LHCP aggregates produced during immunoprecipitation. After a 10 min pulse with /sup 35/SO/sub 4/, the 100,000 dalton proteins constituted over 80% of the immunoprecipitated material. In a subsequent chase, the radioactivity in the 100,000 dalton proteins decreased and the radioactivity in the mature LHCP increased suggesting a precursor-product relationship. After a 35 minute chase, the mature LHCP was the major radioactive protein immunoprecipitated. Peptide mapping and in vitro translation are ...

British Library Electronic Table of Contents (United Kingdom)

Forty synthetic food colors were determined in drinks and candies by reversed-phase high-performance liquid chromatography with photodiode array detection. The following food colors were analyzed within 19min using a short analytical column (50mmx4.6mm i.d., 1.8mm) at 50degreeC with gradient elution: Ponceau 6R, Tartrazine, Fast yellow AB, Amaranth, Indigotine, Naphthol yellow S, Chrysoine, Ponceau 4R, Sunset yellow FCF, Red 10B, Orange G, Acid violet 7, Brilliant black PN, Allura red AC, Yellow 2G, Red 2G, Uranine, Fast red E, Green S, Ponceau 2R, Azorubine, Orange I, Quinoline yellow, Martius yellow, Ponceau SX, Ponceau 3R, Fast green FCF, Eosine, Brilliant blue FCF, Orange II, Orange RN, Acid blue 1, Erythrosine, Amido black 10B, Acid red 52, Patent blue V, Acid green 9, Phloxine B, Ben...

Energy Technology Data Exchange (ETDEWEB)

The overall aim is to develope programme modules for a Danish integrated computer system for projecting buildings and to ensure that Danish programmes are compatible with international systems. The programmes to be integrated here were AutoCAD and SCRIBE-models and the simulation programme tsbi3 for the calculation of indoor climate conditions, power demand and energy consumption in buildings. For the calculation of humidity and temperature conditions in constructions a certain amount of integration is carried out with the MATCH programme (Moisture And Temperature calculations for Constructions of Hygroscopic materials). The activities embodied in the pilot projects are described in this working report in addition to the individual computer programmes and prototypes, and examples and diagrams are presented. The programmes included are a geometry programme for the calculation of areas, lengths and volumes, a programme for the calculation of heat losses in buildings and for moisture in ...

Energy Technology Data Exchange (ETDEWEB)

The aim was to gain experience on how to produce Alkali Metal Thermo-Electric-Converter (AMTEC) cells, for the demonstration of their principles and potentials, as a basis for future commercialization. These cells should be able to present an efficient and direct conversion of thermal energy to electric energy. The system is based on an electro-chemical concentration cell built around a {beta}`` aluminium oxide membrane that separates the two chambers. This material is a good conductor of sodium and a bad conductor of electrons, and it is this property which is taken advantage of. In the two chambers of the cell is found saturated sodium vapour at two temperatures. The motive power is the expansion over the membrane where the sodium ions are transported through it whilst the electrons are forced through the outer cycle. This concept is described in detail in addition to the choice of materials, performance testing and results. It was found possible to produce AMTEC electrodes via ...

CERN Document Server

A new estimator of the local density of dark energy is suggested which comes from the virial theorem for non-relativistic gravitating systems embedded in the uniform dark energy background.

CERN Document Server

We demonstrate the use of a variational method to determine a quantitative lower bound on the rate of convergence of Markov Chain Monte Carlo (MCMC) algorithms as a function of the target density and proposal density. The bound relies on approximating the second largest eigenvalue in the spectrum of the MCMC operator using a variational principle and the approach is applicable to problems with continuous state spaces. We apply the method to one dimensional examples with Gaussian and quartic target densities, and we contrast the performance of the basic Metropolis-Hastings algorithms with a ``smart'' variant that incorporates gradient information into the trial moves. We find that the variational method agrees quite closely with numerical simulations. We also see that the smart MCMC algorithm often fails to converge geometrically in the tails of the target density except in the simplest case we examine, ...

International Nuclear Information System (INIS)

A high-density gas jet supersonic nozzle is reported in this paper. The jitter and actuation time of the nozzle is determined by the pin discharge and laser spark radiation respectively. The jitter time of the nozzle is within 10 ?s with the backing pressure as high as 25 bar. With a nanosecond laser pulse focused on the gas jet about 1 mm below the nozzle, the actuation time is calculated to be about 15 ms by detecting the laser produced spark radiation, which reveals the existence of the gas jet and the relative gas density evolving with time. Consequently the gas density is estimated to be well above 1019 cm-3, compared with theoretical simulations from the nozzle parameters.

International Nuclear Information System (INIS)

... Borisko, VN Tseluyko, AF Zinov'ev, DV Lazurik, VT Kharkov National University,

UK PubMed Central (United Kingdom)

Bone mineral density is considered to be the standard measure for the diagnosis of osteoporosis and the assessment of fracture risk. The majority of fragility fractures occur in patients with bone mineral...Full Text Available

UK PubMed Central (United Kingdom)

The extent (density and diameter) of the native (preexisting) collateral circulation in healthy tissues and the capacity of collaterals to enlarge/remodel in obstructive arterial disease are important...Full Text Available

International Nuclear Information System (INIS)

... 900526-11-8 277 p. MATERIALS SCIENCE antiferromagnetic materials cerium

Science.gov (United States)

... 17 IV. Spatial Amplitude Distributions of Terrain and Sea.....23 Clutter V, Spectral Density Measurements ..... 53 A. Terrain Clutter ..... ...

KoreaScience (Korea)

Full Text Available

Energy Technology Data Exchange (ETDEWEB)

A new method of determining the nuclear level density is presented. This method is based on the statistical analysis of the partial width fluctuations appearing in an excitation function of the radiative proton capture. The method was applied in the case of the /sup 88/Sr(p,..gamma..sub(..omega..))/sup 89/Y and /sup 89/Y(p,..gamma..sub(..omega..))/sup 90/Zr reactions. The density of levels with spin I/sup -/ in /sup 90/Zr and the densities of levels with spins 1/2/sup +/ and 3/2/sup +/ in /sup 89/Y at excitation energies from 10.9 to 11.6 MeV and from 9.3 to 10.8 MeV respectively, were determined with an uncertainty of about 35%.

UK PubMed Central (United Kingdom)

SummaryThe polarized nature of neurons as well as the size and density of synapses complicates the manipulation and visualization of cell biological processes that control synaptic...Full Text Available

Science.gov (United States)

results of motion energy spectral density measurements in the upper atmosphere for the time interval of 5 minutes to 12 hours, in ...

Energy Technology Data Exchange (ETDEWEB)

A nonneutral /sup 7/Li/sup +/ ion plasma is described in which ion Langmuir waves are observed for the first time. The properties of these waves near the Brillouin density limit are investigated.

UK PubMed Central (United Kingdom)

BackgroundAlterations in protein composition and oxidative damage of high-density lipoprotein (HDL) have been proposed to impair the cardioprotective properties of...Full Text Available

International Nuclear Information System (INIS)

The coherent flucton model is applied to the description of some basic nuclear properties, such as: ground state energies, bond energies, nucleon momentum spectra, and nuclear density distributions. It is shown that the momentum distributions of the nucleons coincide with the Fermi distribution for small momenta and exhibit a well pronounced high energy ''tail'', thus providing inclusive reactions of pi-meson generations in kinematically forbidden areas at nucleon-nucleon collisions. Analytical expressions for the bond energy and nuclear density distribution are derived. An agreement with the experimentally obtained data is achieved. The model features are discussed referring to the processes, characterized mainly by the geometric and dynamic properties of the nuclei, as well as by nuclear density distribution. In particular, ion-ion scattering processes at high energy are considered.

British Library Electronic Table of Contents (United Kingdom)

Heavily doped emitters with low saturation current density are of particular interest for selective emitter solar cells. These emitters can be obtained by laser doping through the phosphosilicate glass layer formed after thermal diffusion from POCl3 gas. The experimental results show that in contrast to purely POCl3 furnace-diffused emitters, the saturation current density of laser-doped emitters does not increase linearly as sheet resistance decreases, but rather features two distinct regimes. In one of these regimes, the saturation current density is found to decrease as the sheet resistance decreases, reaching values lower than those of furnace emitters. This peculiar behaviour was explained by both qualitative analysis and numerical simulations.

International Nuclear Information System (INIS)

Isotropic Compton profiles of TaC and TaN have been measured for the first time, at an intermediate resolution, using 662 keV #gamma#-radiation. Energy bands, density of states and Fermi surface topology of TaC and TaN have been computed using linear combination of atomic orbitals with density functional theory and full potential linearised augmented plane wave method. Both band structure calculations predict the metallic character of TaC and TaN. The electron momentum densities calculated using various approaches of density functional theory are compared with the present measurements. On the basis of Mulliken's population, it is also seen that TaC has more covalent bonding than TaN. The optical properties computed using full potential linearised augmented plane wave method are explained in terms of intraband transitions.

British Library Electronic Table of Contents (United Kingdom)

Density functional theory calculations were performed to study the effects of different substituents and bridge groups on the heats of formation (HOFs), thermal stability, and detonation properties for a series of diiminotetrazole derivatives. The isodesmic reaction method was employed to calculate the HOFs of the derivatives using total energies obtained from electronic structure calculations. The bond dissociation energies and bond orders for the weakest bonds were analyzed to investigate the thermal stability of the diiminotetrazole derivatives. The detonation velocities and pressures were evaluated by using the semiempirical Kamlet-Jacobs equations, based on the theoretical densities and HOFs. These results provide basic information for the molecular design of novel high-energy density...

British Library Electronic Table of Contents (United Kingdom)

Fyn is a Src-family tyrosine kinase that affects long term potentiation (LTP), synapse formation, and learning and memory. Fyn is also implicated in dendritic spine formation both in vitro and in vivo. However, whether Fyn's regulation of dendritic spine formation is brain-region specific and age-dependent is unknown. In the present study, we systematically examined whether Fyn altered dendritic spine density and morphology in the cortex and hippocampus and if these effects were age-dependent. We found that Fyn knockout mice trended toward a decrease in dendritic spine density in cortical layers II/III, but not in the hippocampus, at 1month of age. Additionally, Fyn knockout mice had significantly decreased dendritic spine density in both the cortex and hippocampus at 3months and 1year, an...

Science.gov (United States)

The data were collected over three growing seasons. They include density, vegetative biomass, and seed biomass of the two species within the plots. There ... ...

Energy Technology Data Exchange (ETDEWEB)

Spiral orbit tribometry friction tests performed on Ni-rich Ni55Ti45 titanium ball bearings indicate that this alloy is a promising candidate for future aerospace bearing applications. Microstructural characterization of the bearing specimens was performed using transmission electron microscopy and energy dispersive spectroscopy, with NiTi, Ni4Ti3, Ni3Ti, and Ni2Ti4Ox phases identified within the microstructure of the alloy. Density functional theory was applied to predict the electronic structure of the NixTiy phases, including the band structure and site projected density of states. Ultraviolet photoemission spectroscopy was used to verify the density of states results from the density functional theory calculations, with good agreement observed between experiment and theory.

KoreaScience (Korea)

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Science.gov (United States)

... 37 18 Power Spectral Density Measurements of Buffet Pressures for Two Different Microphone Positions Compared with PSD Values Inferred from ...

International Nuclear Information System (INIS)

Doping of manganese (Mn3+/Mn4+) into the Aurivillius phase Pb1-xBi4+xTi4-xMnxO15 was carried out using the molten salt technique for various Mn concentrations (x=0, 0.2, 0.4, 0.6, 0.8, and 1). Single phase samples could be obtained in the composition range with x up to 0.6 as confirmed by X-ray and neutron diffraction analysis. Dielectric measurements show a peak at 801, 803, 813 and 850 K for samples with x=0, 0.2, 0.4, and 0.6, respectively, related to the ferroelectric transition temperature (Tc). The main contribution of the in-plane polarization for x?0.2 which was calculated from the atomic positions obtained by the structure analysis is the dipole moment in the Ti(1)O6 layer; however, for x?0.4 the polarization originates from the dipole moment in the Ti(2)O6 layer. Mn doping in the Pb1-xBi4+xTi4-xMnxO15 does not show any long range magnetic ordering. -- Graphical abstract: The dipole moment of TiO6 dependence of x in Pb1-xBi4+xTi4-xMnxO15 (0?x?0.6): (a) along a-axis and (b) on ...

Energy Technology Data Exchange (ETDEWEB)

A method to deduce the 2 x 2 transport matrix for coupled heat and particle transport in Tokamaks is proposed. The method applies to perturbative experiments, and is based on a Fourier transform of the measured signals of temperature and density. By analyzing different linear combinations of temperature and density, the eigenvectors and eigenvalues of the transport matrix are determined. The method is tested for a number of illustrative cases using simulated data, and the sensitivity to noise on the signals is evaluated. (author).

International Nuclear Information System (INIS)

The analysis of plasma density oscillations and ExB rotation of U-3M torsatron plasma was performed by UHR correlation reflectometry during the transport barrier formation. The connections between these characteristics and the phenomenon of inner and edge transport barrier formation were determined experimentally at the different values of HF power and plasma density.

CERN Document Server

Let ${\\mathcal F}_\\lambda(\\mathbb{S}^n)$ be the space of tensor densities on $\\mathbb{S}^n$ of degree $\\lambda$. We consider this space as an induced module of the nonunitary spherical series of the group $\\mathrm{SO}_0(n+1,1)$ and classify $(\\mathrm{so}(n+1,1),\\mathrm{SO}(n+1))$-sim$unitary submodules of ${\\mathcal F}_\\lambda(\\mathbb{S}^n)$ as a function of $\\lambda$.

Energy Technology Data Exchange (ETDEWEB)

A microscopic calculation of the level density is performed, based on a combinatorial evaluation using a realistic single-particle level scheme. This calculation relies on a fast Monte Carlo algorithm, allowing to consider heavy nuclei (i.e., large shell model spaces) which could not be treated previously in combinatorial approaches. An exhaustive comparison of the predicted neutron s-wave resonance spacings with experimental data for a wide range of nuclei is presented.

Energy Technology Data Exchange (ETDEWEB)

The strength of adhesion of polybutylene terephthalate (PBT) on aluminium is investigated using density functional theory-based energy calculations. The aluminium atom is connected to a PBT monomer at different orientations, and total energies are calculated and compared to determine the most stable orientation. The binding is strongest when the Al is oriented at 180{sup 0} to the ester group of the monomer. Using this orientation as a basis, PBT adhesion on Ti, Ag, and Au is also investigated.

International Nuclear Information System (INIS)

The optical properties of uranium monochalcogenides and monopnictides are discussed in terms of their electronic structure. A comparison is made with corresponding rare earth compounds. It is shown that there are close similarities to mixed valence CeN. the results support the occurrence of a dip in the density of d states near Esub(F), where the f density of states has its maximum. Empirical energy level schemes are derived which are found to agree with the existing information from XPS measurements and recent theories. (orig.).

Science.gov (United States)

A mathematical model describing the behavior of a gas of any density released into a turbulent atmosphere was developed. A numerical treatment was established for two dimensional flow. An understanding of the effects of accidental or continuous release wa...

Science.gov (United States)

In this work, energy-based features for gear fault diagnosis and prediction are proposed. The instantaneous energy density is shown to obtain high values when defected teeth are engaged. Three methods are compared in terms of sensitivity, reliability and computation effectiveness. The Wigner Ville distribution is contrasted to the wavelet transform and the newly proposed empirical mode decomposition scheme. It is shown that all three methods are capable of a reliable prediction. An empirical law, which relates the energy content to the crack magnitude is established.

Wastenet

...Correction Discussion Editorial Letter Opinion Review Short Note Technical Note Special Issue all A Systematic Development Method for Rational Drug Design Advances in Molecular Electronic Structure Calculations Algorithms and Molecular Sciences Antimicrobial Agents Application of Density Functional Theory Applications of Density Functional Theory Applications of Molecular Dynamics Atoms in Molecules ...

International Nuclear Information System (INIS)

A radiometric method was elaborated for surface density determinations of the adhesive layer of plasters by radionuclide X-ray fluorescence using the 17.47 keV bremsstrahlung of "1"4"7Pm/Mo. The bremsstrahlung line excites the 8.63 keV characteristic K#alpha# line of Zn contained in the adhesive layer of the plaster as a filling material in the form of ZnO. In homogeneous adhesive layers the Zn content is proportional to surface density. (author).

British Library Electronic Table of Contents (United Kingdom)

Layered carbon fiber mats have been prepared by layer-by-layer (LBL) electrospinning of polyacrylonitrile onto thin natural cellulose paper and subsequent carbonization. The layered carbon fiber mat has been proved to be a promising microbial fuel cell anode for high density layered biofilm propagation and high bioelectrocatalytic anodic current density.