1,757,903 research outputs found
Temperature classification of the spectra of dysprosium (Dy I, Dy II)
No full textThe Temperature Classifications are listed for 4584 lines of Dy I and Dy II, as taken from an unpublished manuscript of the late A. S. King. In recording his observations, King used a wavelength list compiled mostly from the early literature. A homogeneous and extensive line list based on new observations has been prepared at the Lawrence Radiation Laboratory (LRL). King's data have been edited and adjusted by the present authors to fit the new wavelength list. In the Table, King's estimated intensities of Dy lines in the spectra of the Arc, Spark, and Furnace are given along with the Temperature Classification. Some of his earlier published work has been used to fill the gaps in this manuscript, which was forwarded to the late W. F. Meggers in 1956
Polymeric micelles and the Dy-166/Ho-166 generator: A study of the loading mechanism of Dy/Dy-166 and Ho-166 into PCL-b-PEO polymeric micelles for imaging and cancer treatment
No full textA radioisotope used in radionuclide therapy is Holmium-166 (Ho-166). The treatment effectiveness of Ho-166 could be improved by the use of a so called in vivo Dysprosium-166(Dy-166)/Ho-166 generator. The application of this generator is hindered by an effect called internal conversion (IC). This affect can arise after the decay of Dy-166 to Ho-166, which can cause separation of Ho-166 from its carrier.Polymeric micelles might form a solution in the application of the Dy-166/Ho-166 generator in radionuclide therapy. The main goal of this thesis was to investigate and understand the loading mechanism of metallic species and polymeric micelles with a focus on the loading of Dy/Dy-166 and Ho-166. It was found that it was not effective to load metallic species (Dy/Dy-166) as free ions or as solid precipitates. Loading metallic species as aqueous hydroxides showed to be crucial for achieving a good loading and high stability. The second goal was to study if polymeric micelles were able to retain Ho-166 inside their core under the effects of internal conversion. No additional losses of Ho-166 were found when Dy/Dy-166 and Ho-166 were loaded into the micelles. It was concluded that the PCL-PEO micelles prevented the loss of Ho-166 under internal conversion effects.Applied Science
Modeling Dynamic architectures using Dy-BIP
No full textBest Paper AwardInternational audienceDynamic architectures in which interactions between components can evolve during execution, are essential for modern computing systems such as web-based systems, reconfigurable middleware, wireless sensor networks and fault-tolerant systems. Currently, we lack rigorous frameworks for their modeling, development and implementation. We propose Dy-BIP a dynamic extension of the BIP component framework rooted in rigorous operational semantics and supporting a powerful and high-level set of primitives for describing dynamic interactions. These are expressed as symbolic constraints offered by interacting components and computed efficiently by an execution Engine. We present experimental results which validate the effectiveness of Dy-BIP and show significant advantages over using static architecture models
Computer Simulation of Enhancement of Coerciviy in Nd-Fe-B/(Nd,Dy)-Fe-B Composite Magnets
No full textThe coercivity Hc of Nd2Fe14B magnets and Nd2Fe14B/(Nd0.7Dy0.3)2Fe14B composite magnets were calculated by computer simulation based on the micromagnetic theory under assumptions that Nd2Fe14B and (Nd0.7Dy0.3)2Fe14B grains have magnetically deteriorated layers on their surfaces and diffusion of Dy from (Nd0.7Dy0.3)2Fe14B grains to Nd2Fe14B ones through the contacting boundaries recovers the magnetic anisotropy of the deteriorated layers of Nd2Fe14B grains. Hc of Nd2Fe14B/(Nd0.7Dy0.3)2Fe14B composite magnets increased by the diffusion of Dy from (Nd0.7Dy0.3)2Fe14B grains to Nd2Fe14B ones and the resultant recovery of the anisotropy field of deteriorated layers of Nd2Fe14B grains. The Hc vs fraction of (Nd0.7Dy0.3)2Fe14B grains curve were convex for the magnets with the degree of alignment between 0.94 and 0.99, which suggests that the above composite magnets have larger Hc values than the alloy-magnets with the same Dy content, and that we can save the consumption of Dy by using these composite magnets
A Study on the Characteristics of Cu-Mn-Dy Alloy Resistive Thin Films
No full textCu-Mn-Dy resistive thin films were prepared on glass and Al2O3 substrates, which was achieved by co-sputtering the Cu-Mn alloy and dysprosium targets. The effects of the addition of dysprosium on the electrical properties and microstructures of annealed Cu-Mn alloy films were investigated. The composition, microstructural and phase evolution of Cu-Mn-Dy films were characterized using field emission scanning electron microscopy, transmission electron microscopy and X-ray diffraction. All Cu-Mn-Dy films showed an amorphous structure when the annealing temperature was set at 300 degrees C. After the annealing temperature was increased to 350 degrees C, the MnO and Cu phases had a significant presence in the Cu-Mn films. However, no MnO phases were observed in Cu-Mn-Dy films at 350 degrees C. Even Cu-Mn-Dy films annealed at 450 degrees C showed no MnO phases. This is because Dy addition can suppress MnO formation. Cu-Mn alloy films with 40% dysprosium addition that were annealed at 300 degrees C exhibited a higher resistivity of 2100 cm with a temperature coefficient of resistance of -85 ppm/degrees C.IM
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
beta-delayed proton decays and spin assignments for Tb-140, Dy-141 and Dy-143
No full textThe proton-rich isotopes Tb-140 and Dy-141 were produced via the fusion evaporation reaction Ca-40+ Cd-106. Their beta-delayed proton decays were studied by p-gamma coincidence in combination with a He-jet tape transport system, and half-lives, proton energy spectra, gamma-transitions following the proton emission, as well as beta-delayed proton branching ratios to the low-lying states in the grand-daughter nuclei were determined. Comparing the experimental data with statistical model calculations, the ground-state spins of Tb-140 and Dy-141 were found to be consistent with 7 and 9/2, respectively. The configuration-constrained nuclear potential energy surfaces (NPES) of Tb-140 and Dy-141 were calculated using the Woods-Saxon-Strutinsky method, which suggest the ground-state spins and parities of Tb-140 and Dy-141 to be 7(+) and 9/2(-), respectively. In addition, the configuration-constrained NPES of Dy-143 were calculated, which predict a 1/2(+) ground state and a 11/2(-) isomer with excitation energy of 198 keV. These findings are consistent with our previous experimental data on Dy-143 reported in Eur. Phys. J. A 16, 347 (2003).Physics, NuclearPhysics, Particles & FieldsSCI(E)3ARTICLE137-402
Dy/Dy*: Variations Arising from Mantle Sources and Petrogenetic Processes
No full textDy/Dy* is the measured value of Dy, a representative middle rare earth element (REE), compared with the value interpolated between La and Yb on a REE plot. It is essentially a measure of the ‘concavity’ of a REE pattern. The use of Dy/Dy* as a proxy for REE pattern shape allows us to compare large amounts of REE data, which can be difficult using standard REE patterns. When Dy/Dy* is combined with Dy/Yb (the slope of the middle-to-heavy REE pattern) REE patterns can effectively be classified by shape. We present a new set of high-quality REE (and other trace element) data for young volcanic rocks from six arcs. When plotted on the Dy/Dy*–Dy/Yb diagram they define a broad negative correlation from LREE-depleted (Tonga–Kermadec) to LREE-enriched (Philippines and Indonesia). This trend corresponds to decreasing Dy/Dy*, reflecting REE patterns varying from concave-down to concave-up respectively. When cogenetic suites from single volcanoes are plotted they define clear trends of decreasing Dy/Yb and Dy/Dy* with differentiation, roughly orthogonal to the general depletion–enrichment trend. The trends for single arc volcanoes are interpreted as most probably reflecting an amphibole control, consistent with the concomitant decreases in Ti/Ti* and increasing SiO2. Available distribution coefficients are, however, also permissive of cpx control on arc REE patterns. Estimated compositions of the continental crust fall along these same trends. In contrast, ocean island basalt (OIB) data all fall to high Dy/Yb, suggesting a significant control by garnet. A global consideration of the data suggests that (1) arc magmas are derived from variably depleted asthenospheric (mid-ocean ridge basalt) mantle sources, (2) arc magma (and continental crust) differentiation is controlled by a mineral phase (or phases) that preferentially partitions MREE and (3) OIB genesis appears to always involve garnet control. We propose that Dy/Dy* is potentially a powerful tool for representing the shapes of REE patterns, especially for large datasets. We also note the importance of using cogenetic rock suites to identify petrogenetic processes rather than regional suites
Binding Mode between Trp-Dy(III) Complex and Herring Sperm DNA
No full textBy means of UV and fluorescence spectra, the binding ratios between Dy(III)(Trp)(3) and DNA. in physiological pH environment(pH7.40) were determined as n(Dy(III)(Trp)),:n(DNA) = 2:1 and n(Dy(III)):n(Trp)=1:3. The binding constant of K-25 degrees C= 5.75 x 10(7) L.mol(-1) and K-37 degrees C=3.27 x 10(5) L.mol(-1) were obtained by double reciprocal method. Thermodynamic function computation demonstrates that Delta S-r(m)circle minus and Delta H-r(m)circle minus are the primary driving power of the interaction between Dy(III)(Trp)(3) and DNA. By combination analysis of the Scatchard and viscometry methods, we suggested that the interaction mode between Dy(III)(Trp)(3) complex and herring sperm DNA be electrostatic and intercalation bindings
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