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The process of radiation-chemical coloration of CsI(T1) crystals with different carbonate ion Contamination has been studied. The presence of carbonate in the CsI(T1) crystals deteriorates their photo- and radiation stability. Possible reasons for the charge carrier delocalization in CsI(T1) crystals under exposure to daylight and a role of oxygen-containing impurities in the formation of stable radiation defects have been established. A model of the hole activator color center is suggested. According to the model, the [T1.sup.2+] [v.sup.-.sub.c] center is a [T1.sup.2+] hole activator center perturbed by a cation vacancy. The electron color centers [T1.sup.0] [v.sup.+.sub.a] are stabilized not only by the hole color centers of [T1.sup.2+] [[v.sup.-.sub.c] and [I.sup.-.sub.3], but also by the molecular anions of HC[O.sup.-.sub.3] and C[O.sup.-.sub.3] formed as a result of the photo- and radio-chemical transformation of C[O.sup.2-.sub.3] and O[H.sup.-] ions. Index Terms--Cesium compounds, infrared spectroscopy, photochromism, radiation effects.

Results of the investigation confirmed a possibility of forming artificial microbial consortia based on the blue-green algae (cyanobacteria) Nostoc paludosum. Such associations maintained their structure and activity drying long-term cultivation on the liquid mineral medium in a collection under stable conditions. Compatibility of blue-green algae with Rhizobium leguminosarum. R. galegae, Agrobacterium radiobacter, Pseudomonas fluorescens, and Azospirillum lipoferum is discussed. We have demonstrated the stability of artificial double and triple consortia and arrangement of the partners in them without Azospirilla. The comparison of the seed treatment of Galega orientalis with R. galegae only and seed treatment by consortia Nostoc paludosum + R. galegae showed significant advantages of the consortia inoculation. Prospects of using artificial algal-bacterial associations in agricultural biotechnology are discussed. [ABSTRACT FROM AUTHOR]

Abstract: Spectral-kinetics properties of photo-scintillation excited with single light pulses of a nitrogen laser (λ=337.1nm, t 1/2=5ns, Q=1mJ) have been studied in CsI:Eu crystals at temperature within 80–300K. It is found that the exponential decay of 463nm emission band has a time constant which grows from 0.85μs at 78K to 1.6μs at 380K. Such an anomalous temperature behavior of 463nm emission decay kinetics is discussed in terms of the crystal thermal expansion. It has been proposed that 463nm emission is caused by a cluster center consisting of three dipoles Eu2+vc − bounded with each other in a hexagon. Owing to the exchange resonance in the cluster, the energy passes from an excited dipole to a non-excited one and the distance between them gets longer due to thermal expansion of the crystal. [Copyright &y& Elsevier]

Ce3+-activated YCl3 crystals have been grown by the Bridgman-Stockbarger method, and their scintillation properties have been investigated. The luminescence spectrum of YCl3:Ce has a complex character and consists of two overlapping peaks at 390 and 410 nm, characteristic of Ce3+ luminescence. The light output of YCl3:Ce as a function of Ce3+ concentration has a maximum at 1 mol % Ce3+. [ABSTRACT FROM AUTHOR]