The Radiochemical Analysis of Gaseous Samples (RAGS) Apparatus for Nuclear Diagnostics at the National Ignition Facility

The RAGS (Radiochemical Analysis of Gaseous Samples) diagnostic apparatus was recently installed at the National Ignition Facility. Following a NIF shot, RAGS is used to pump the gas load from the NIF chamber for purification and isolation of the noble gases. After collection, the activated gaseous species are counted via gamma spectroscopy for measurement of the capsule areal density and fuel-ablator mix. Collection efficiency was determined by injecting a known amount of {sup 135}Xe into the NIF chamber, which was then collected with RAGS. Commissioning was performed with an exploding pusher capsule filled with isotopically enriched {sup 124}Xe and {sup 126}Xe added to the DT gas fill. Activated xenon species were recovered post-shot and counted via gamma spectroscopy. Results from the collection and commissioning tests are presented. The performance of RAGS allows us to establish a noble gas collection method for measurement of noble gas species produced via neutron and charged particle reactions in a NIF capsule

Chemical Identification of a Long-Lived Isotope of Dubnium, a Descendant of Element 115

The recognition criterion for discovery of a new chemical element includes two aspects, the characterization properties and the assignment properties. In this paper, we will discuss the status of element 115 experiments that have been performed in Dubna, Russia, highlighting the characterization and assignment properties as they specifically relate to a recent experiment. After discussing the status of what is known about the decay properties of element 115 [1], observed previously using the Dubna Gas-Filled Recoil Separator, we will discuss the prior chemical studies that have been performed on the Db descendant of element 115 [2]. Following the success of that experiment, some additional chemical information was desired. Two separation chemistries were then developed at LLNL and JINR. LLNL utilized reversed phase chromatography and JINR utilized anion exchange chromatography to perform not only +4/+5 separations, but also intra-group separations, where Nb-like and Ta-like fractions were eluted. The results from an experiment using these chemistries for the first time during December 2005 in Dubna, Russia, will be compared with prior chemical results. We will conclude with a discussion of possible enhancements to the work already performed and the current status of the future experimental plans

Fusion reaction 48Ca+249Bk leading to formation of the element Ts (Z=117)

The heaviest currently known nuclei, which have up to 118 protons, have been produced in 48Ca induced reactions with actinide targets. Among them, the element tennessine (Ts), which has 117 protons, has been synthesized by fusing 48Ca with the radioactive target 249Bk, which has a half-life of 327 d. The experiment was performed at the gas-filled recoil separator TASCA. Two long and two short α decay chains were observed. The long chains were attributed to the decay of 294Ts. The possible origin of the short-decay chains is discussed in comparison with the known experimental data. They are found to fit with the decay chain patterns attributed to 293Ts. The present experimental results confirm the previous findings at the Dubna Gas-Filled Recoil Separator on the decay chains originating from the nuclei assigned to Ts

First evidence of metal transfer into hydrophobic deep eutectic and low-transition-temperature mixtures: indium extraction from hydrochloric and oxalic acids

International audienceThis is the first report on metallic species transfer from aqueous hydrochloric and oxalic acid media into hydrophobic deep eutectic and low-transition-temperature mixtures composed of quaternary ammonium salts or menthol and carboxylic acids

Characterization and application of alkanethiolate self-assembled monolayers on Au-coated chips for Ir(IV) and Rh(III) sorption

International audienceAu-coated Si alpha-particle detectors have been widely used during the chemical characterization of superheavy elements that have been an area of great interest to scientists for decades. Further experiments are aimed at the functionalization of this type of detector to study the chemical properties of meitnerium. It is expected to be a member of the group 9 elements of the periodic table, and its chemical properties have not been studied before. In this study, self-assembled monolayers (SAMs) of 1-(11-mercaptoundecyl)imidazole (Im-C11-SH) and 12-mercaptododecanoic acid (MDDA) on 1 x 1 cm2 Au-coated Si and glass chips were prepared and characterized using several analytical and optical techniques: atomic force microscopy (AFM), nanoprojectile secondary ion mass spectrometry (NP-SIMS), X-ray photoelectron spectroscopy (XPS), ellipsometry, and instrumental neutron activation analysis (INAA). The coverage of Au-coated Si chips with Im-C11-SH SAMs was (99 +/- 6)%. NP-SIMS showed quantitative sorption of Rh(III) from an HCl medium, the coverage of Im-C11-SH SAMs with Rh(III) was (81.3 +/- 3.8)%. INAA showed quantitative sorption of Ir(IV) and illustrated that it can be adsorbed from a 5.4 mu M initial Ir(IV) solution in 0.55 M HCl on the Im-C11-SH and MDDA SAMs with a surface saturation of (77 +/- 12)% and (84 +/- 16)%, respectively