A remarkable new leaf-cutter bee from Thailand (Hymenoptera: Megachilidae)

This is the publisher's version, copyright by Akademie Verlag.A remarkable new species of leaf-cutter bee, Megachile trichorhytisma ENGEL sp. n., is described and figured from two males collected in northern Thailand. The species is placed in a new subgenus, Aethomegachile ENGEL & BAKER subgen. n., and is differentiated from previously known lineages of Megachile

Rapid Stabilization of Sands with Deep Mixing Method Using Polyester

Rapid stabilization of weak soils is one of the important and current topics in geotechnical researches such as military application and stabilization of landslides. Deep mixing is an improvement method applied in the form of creating mixed columns which involves in-situ mixing of soil and lime or Portland cement with special equipment. The aim of this study was to evaluate the feasibility of utilizing polymers as a binder for rapid stabilization of sandy soils with deep mixing method. For this purpose, a series of unconfined compression tests were conducted on three dierent sandy soils improved with polyester. In the experiments, polyester was used at three dierent ratios of 10%, 20% and 30% and samples cured for 3 hour, 1, 3, 7 and 28 days. The laboratory test results of 3 hours samples showed that soils mixed with adequate polyester could reach a similar strength range of 28 days cured soils improved with cement or lime which was reported in the literature. The unconfined compressive strength increased with the increasing polyester ratio, effective diameter, and relative density and curing period, whereas, the changes on unconfined compressive strength were insignificant with the increase of freeze-thaw cycles. The overall evaluation of results has revealed that polyester is a good promise and a potential candidate for rapid deep mixing applications