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H. Bharti and I. Gul

Echinopla Cherapunjiensis sp. n. (Hymenoptera, Formicidae) from India

Echinopla cherapunjiensis Bharti et Gul, sp. n. is described from India. This represents the second species of genus reported in India, with only Echinopla lineata senilis Mayr, 1862 described earlier from Nicobar Islands. The species distinctly differs from all other known species of this genus by the following combination of characters: globose shape of head, presence of seven teeth on petiolar scale, flat dorsum of mesosoma with promesonotal and mesometanotal sutures obsolete, whole body surface (dorsum) rough due to sinuous sculpture, deep excavations and spiky elevations on head and mesosoma and excavations on gaster.

Open access

P. Petkova, P. Vasilev, Gulsah Celik Gul, M. Mustafa and I. Parushev

Abstract

The absorption coefficient of Bi12TiO20:AlI, Bi12TiO20:AlII, Bi12SiO20:P and Bi12SiO20:Al+P single crystals is measured in the spectral region of Urbach’s rule (1.52 – 2.92 eV) at room temperature. The parameters of electron-phonon interaction, Urbach’s energy and the constants of Urbach’s rule are calculated. The behavior of the acceptors Al3+ and P5+ in Urbach’s rule region has been considered.