Interaction between UN and CdCl2 in molten LiCl-KCl eutectic. I. Experiment at 773 K

The interaction between UN and CdCl2 in the LiCl-KCl molten eutectic was studied at 773 K. The reaction was controlled by sampling the melt, as well as by analysis of the resulting precipitate. The process was shown to proceed according to several parallel reactions. The summary reaction was determined to have two stages: a fast one and a slow one. The 19–53% UN → UCl3 conversion was obtained for the molar ratio of CdCl2/UN = 1.22–14.9. The rest of UN converts into the precipitate of complex composition (UNCl + U2N3 + U4N7 + UN2). The increase in the CdCl2/UN molar ratio from 1.22 to 14.9 resulted in the decrease in duration of the first “fast” stage of the process from 18 h to 1 h. © 201

Interaction between UN and CdCl2 in Molten LiCl–KCl Eutectic. II. Experiment at 1023 K

The interaction between UN and CdCl2 in the LiCl–KCl molten eutectic was studied at 1023 K. The chlorination was monitored by sampling and recording the redox potential of the medium. At 1023 K the chlorination of UN with cadmium chloride in the molten LiCl–KCl eutectic proceeds completely and results in the formation of uranium chlorides. The melts of the LiCl–KCl–UCl3 or LiCl–KCl–UCl4 compositions can be obtained by the end of experiment depending on the presence of metallic cadmium in the reaction zone. The higher the concentration of the chlorinating agent, the faster the reaction rate. At [CdCl2]/[UN] = 1.65 (10% excess) the reaction proceeds to completion in about 7.5 h. At [CdCl2]/[UN] = 7 the complete chlorination takes 2.5–3 h. © 2021.The authors gratefully acknowledge for analytical support of the Shared Access Centre "Composition of Compounds" of the Institute of High Temperature Electrochemistry of the Ural Branch of the Russian Academy of Sciences. The present research was partially performed within the Proryv (Breakthrough) project of State Atomic Energy Corporation Rosatom

Towards crystal structure prediction of complex organic compounds - a report on the fifth blind test

Following on from the success of the previous crystal structure prediction blind tests (CSP1999, CSP2001, CSP2004 and CSP2007), a fifth such collaborative project (CSP2010) was organized at the Cambridge Crystallographic Data Centre. A range of methodologies was used by the participating groups in order to evaluate the ability of the current computational methods to predict the crystal structures of the six organic molecules chosen as targets for this blind test. The first four targets, two rigid molecules, one semi-flexible molecule and a 1: 1 salt, matched the criteria for the targets from CSP2007, while the last two targets belonged to two new challenging categories - a larger, much more flexible molecule and a hydrate with more than one polymorph. Each group submitted three predictions for each target it attempted. There was at least one successful prediction for each target, and two groups were able to successfully predict the structure of the large flexible molecule as their first place submission. The results show that while not as many groups successfully predicted the structures of the three smallest molecules as in CSP2007, there is now evidence that methodologies such as dispersion-corrected density functional theory (DFT-D) are able to reliably do so. The results also highlight the many challenges posed by more complex systems and show that there are still issues to be overcome

EFFICIENCY OF COLLECTIVE MOOSE HUNTING IN A FOREST-TAIGA ZONE OF RUSSIA

We discuss results of hunting moose by coordinated drives by various-sized hunting groups in the Kirov region. We report the optimum size of a hunting brigade, its advantages over hunting by individuals or by small groups, and the opportunity for selective harvest by sex and age classes

Chemical composition of basalts and andesites from the Sea of Japan

An investigation of uranium and thorium contents in extrusive rocks from underwater rises in the Sea of Japan demonstrates that concentrations of these radioactive elements can be used as indicators of geodynamic conditions. It is concluded that basalt volcanism of the Sea of Japan is of continental type

Frequency doubling of 859.2 nm radiation in a waveguide formed from Nb2O5 and Ta2O5 films on a KTiOPO4 substrate

It is proposed that second harmonic generation in a waveguide formed from Nb2O5 and Ta2O5 films on a KTiOPO4 crystal substrate can be used to obtain blue coherent radiation. It is shown that the second harmonic generation efficiency in a thin-film stripe waveguide may reach 1010% W-1 ·cm-2, and the spectral phase-matching width may reach 0.45 nm·cm. Generation of the second harmonic of 859.2 nm laser radiation was observed experimentally in a Ta2O5-Nb2O5-KTiOPO4 waveguide. © 1999 American Institute of Physics