U and Pu separation with U/TEVA resin: Influence of some parameters on chromatographic cycle performances

Journal of Radioanalytical and Nuclear Chemistry - Due to unexpected Pu behavior using the U/TEVA resin and the most-recognized reagents, some key separation stages need to be studied for the...     

Measurement of the total active 8B solar neutrino flux at the Sudbury Neutrino Observatory with enhanced neutral current sensitivity

The Sudbury Neutrino Observatory has precisely determined the total active (nu(x)) 8B solar neutrino flux without assumptions about the energy dependence of the nu(e) survival probability. The measurements were made with dissolved NaCl in heavy water to enhance the sensitivity and signature for neutral-current interactions. The flux is found to be 5.21 +/- 0.27(stat)+/-0.38(syst) x 10(6) cm(-2) s(-1), in agreement with previous measurements and standard solar models. A global analysis of these and other solar and reactor neutrino results yields Deltam(2)=7.1(+1.2)(-0.6) x 10(-5) eV(2) and theta=32.5(+2.4)(-2.3) degrees. Maximal mixing is rejected at the equivalent of 5.4 standard deviations.     

Synthesis and properties of a functionalized heterobimetallic Re(I)–Gd(III) complex as a potential dual-contrast agent for molecular imaging

In the design of dual-imaging probes, the first functionalized and neutral heterobimetallic Re(I)–Gd(III) complex, highly soluble in aqueous solutions, has been prepared. This system exhibits interesting photophysical properties (λ_em = 578 nm, ? = 1.4%) for optical imaging and substantial higher relaxivity (r₁ = 6.6 mM⁻¹ s⁻¹ at 0.47 T and 37 °C) than the clinically used MRI contrast agents. Moreover, this system incorporates an aromatic ester functionality suitable for bioconjugation.     

Independent measurement of the total active 8B solar neutrino flux using an array of 3He proportional counters at the Sudbury Neutrino Observatory

The Sudbury Neutrino Observatory (SNO) used an array of 3He proportional counters to measure the rate of neutral-current interactions in heavy water and precisely determined the total active (nu_x) 8B solar neutrino flux. This technique is independent of previous methods employed by SNO. The total flux is found to be 5.54_-0.31;+0.33(stat)-0.34+0.36(syst)x10(6) cm(-2) s(-1), in agreement with previous measurements and standard solar models. A global analysis of solar and reactor neutrino results yields Deltam2=7.59_-0.21;+0.19x10(-5) eV2 and theta=34.4_-1.2;+1.3 degrees. The uncertainty on the mixing angle has been reduced from SNO's previous results.     

GdAlO3 perovskite

Flux‐grown gadolinium aluminate perovskite, GdAlO₃, was examined using single‐crystal 0.7 Å‐wavelength synchrotron X‐ray diffraction. In the context of other well categorized rare earth aluminate (RAlO₃) perovskite phases, the orthorhombic Pnma symmetry determined for the current compound is unsurprising. Corner‐linked AlO₆ octahedra form the structural backbone of RAlO₃ perovskites and distort to accommodate the various rare earth ions in the structural voids. For GdAlO₃, the octahedral distortion, characterized by tilting of the octahedra about the shortest R—Al—R vectors, and octahedral deformation, characterized by strain of the octahedra along those axes, are in accordance with trends in the RAlO₃ series.     

Morphogenesis of polyoxometalate cluster-based materials to microtubular network architectures

Pressed pellets of polyoxometalate (POM)-based materials are shown to undergo morphogenesis to produce microtubular network architectures without the need for a large single crystal precursor. The compression of the POM material into a pellet lowers the solubility sufficiently to allow tube initiation and growth from POMs that would otherwise be too soluble in their native crystalline state, thus yielding hollow, highly controllable, tubes of diameter 10-100 μm.     

Synchrotron X‐ray study of ortho­rhombic Rb3Ta5O14 with a modified pyrochlore structure

The structure of a new orthorhombic trirubidium pentatantalum oxide (Rb₃Ta₅O₁₄) phase with Pnma symmetry was identified from a half sphere of synchrotron X‐ray data measured at a wavelength of 0.85 Å. This notionally linked TaO₆ octahedral structure broadly consists of three different modifications of the pyrochlore ring motif with layer stacking normal to (205) planes. Successive pyrochlore layers do not simply stack normal to these planes but are offset along the [100] axis. An unusual aspect of this structure is the occurrence of TaO₅ trigonal bipyramids in structurally complex regions where the modified pyrochlore rings connect.     

Paper sheet moisture measurements in the far infrared

Measurement of several parameters pertinent to process and quality control in the manufacture of paper products is a potentially important application of far-infrared lasers. Preliminary measurements of the transmittance and reflectance of moist paper sheets are presented, and their use to determine the percentage moisture content and the dry basis weight of the paper is discussed.