Angular distribution of characteristic photons after radiative electron capture at strong central fields

We investigate the difference in the angular distribution of Ly-alpha(1) and K alpha(1) photons from hydrogenlike and heliumlike ions of uranium after radiative electron capture to the L shell. The strong anisotropy in the former case is changed to a very small one in the latter case. Our calculations support the observation. The effect takes place even in the limiting case of noninteracting electrons, being caused by the Pauli principle.

Systematics of central heavy ion collisions in the 1A GeV regime

Using the large acceptance apparatus FOPI, we study central collisions in the reactions (energies in A GeV are given in parentheses): Ca-40 + Ca-40 (0.4, 0.6, 0.8, 1.0, 1.5, 1.93), Ni-58 + Ni-58 (0.15, 0.25, 0.4), Ru-96+Ru-96 (0.4, 1.0. 1.5), (96)zr+(96)zr 1.0, 1.5), Xe-129+CsI (0.15, 0.25, 0.4), Au-197 + Au-197 (0.09, 0.12, 0.15, 0.25, 0.4, 0.6, 0.8, 1.0, 1.2, 1.5). The observables include cluster multiplicities, longitudinal and transverse rapidity distributions and stopping, and radial flow. The data are compared to earlier data where possible and to transport model simulations. (C) 2010 Elsevier B.V. All rights reserved.

Synthesis of novel ferrocenylphosphine-amidine ligands with central and planar chirality and their diastereomeric effect in Pd-catalyzed asymmetric allylic alkylation

Some novel ferrocenylphosphine-amidine ligands with central and planar chirality were prepared from (R,S-p)-PPFNH2-R 3 and its diastereomer (S,S-p)-PPFNH2 3a. The efficiency and diastereomeric impact of these ferrocenylphosphine-amidine ligands in the palladium-catalyzed asymmetric allylic substitution was examined, and up to 96% e.e. with 98% yield was achieved by the use of ligand (R,S-p)-4a with a methyl group in the amidino moiety. The results also indicated that (R)-central chirality and (S-p)-planar chirality in these ferrocenylphosphine-amidine ligands were matched for the palladium-catalyzed asymmetric allylic alkylation. (C) 2003 Elsevier Ltd. All rights reserved.

Synthesis of novel P-ketimine bidentate ferrocenyl ligands with central and planar chirality and comparsion in the catalytic activity between P-ketimine and P-aldimine

A series of novel ferrocenylphosphine-ketimine ligands 6 were prepared by reaction of (R,S-p)-PPFNH2-R or (S,S-p)-PPFNH2 with a variety of m-substituted acetophenones. A different catalytic activity was observed between ferrocenylphosphine-ketimine ligands and corresponding aldimine ligands. The efficiency and diastereomeric impact of these ferrocenylphosphine-ketimine ligands in Pd-catalyzed asymmetric allylic alkylation were first investigated, and higher enantioselectivity of over 98% e.e. with 95% yield was obtained by the use of ferrocenylphosphine-ketimine ligands. However, in Rh-catalyzed asymmetric hydrosilylation of aryl ketones, only 42% e.e. was obtained by the use of ferrocenylphosphine-ketimine ligands compared to 90% e.e. with the use of aldimine ligands. (C) 2003 Elsevier Ltd. All rights reserved.

Reconstructing temperature change in Central East China during 601-920 AD

Chinese Academy of Sciences [KZCX2-YW-Q1-01, KZCX2-YW-315]; National Natural Science Foundation of China [40625002]

Digital regionalization of geomorphology in Xinjiang

National Natural Science Foundation of China [40871177]; Project of State Key Lab of Resources and Environmental Information System [088RA304SA]; CAS Knowledge Innovation Project

A methodology of characterizing status and trend of land changes in oases: A case study of Sangong River watershed, Xinjiang, China

National Natural Science Foundation of China [40471134]; program of Lights of the West China by the Chinese Academy of Science

Alteration mineral mapping using masking and Crosta technique for mineral exploration in mid-vegetated areas: a case study in Areletuobie, Xinjiang (China)

Thematic Mapper (TM) and Enhanced Thematic Mapper (ETM)+ data have been successfully employed in the field of mineral exploration to identify key minerals over arid and semi-arid terrains. However, redundant vegetation and cloud may seriously interfere with the discrimination of the minerals with diagnostic features. Therefore, in this study, we use masking technique to eliminate the negative influence of vegetation and cloud and Crosta technique to identify the diagnostic features of hydroxyl-minerals, carbonate-minerals and iron oxides. Then the anomalies were endowed with special colours and overlapped with the remote-sensing and geochemical data, overlaying images as remote-sensing anomalies. The mineral exploration work was carried through by synthetic analysis of the remote-sensing images, geochemical data and structures. Finally, areas with high correlation between the occurrence of hydrothermal alteration and presence of main faults and geochemical anomalies were considered as mineral exploration targets worthy of further detailed exploration programmes.