Amongst the materials collected from the Cambrian outcrops in the Holy Cross Mountains by priest professor Włodzimierz Sedlak, there is a holotype and only specimen of Helcionella polonica, as well as a rock fragment with casts of medusoids on its surface. We decided to revise these materials for their importance to discussions on the early molluscs’ size and the medusae fossil record; as well as for the critical nature of previously published revisions of taxa erected by Sedlak.
2
Dostęp do pełnego tekstu na zewnętrznej witrynie WWW
Przedstawiono badania procesu chłodzenia strefy obróbki z wykorzystaniem systemu sprężonego powietrza współpracującego z robotem przemysłowym. Zaprezentowano również możliwości adaptacji systemu chłodzenia sprężonym powietrzem do realizacji procesu szlifowania oraz skrawania, z uwzględnieniem specyfiki współczesnych urządzeń obróbkowych CNC.
EN
The article presents a study on the process of cooling processing zone with the use of compressed air system cooperating with the industrial robot. The paper also presents the possibility of adapting the system of cooling the compressed air to the process of grinding and cutting taking into account the specificity of modern CNC machining equipment.
The present article concerns a characteristics of enigmatic encrusting organisms of the order Microconchida (microconchids), similar to polychaetes of the genus Spirorbis, as well as a description of their finds from the Upper Carboniferous of the Upper Silesia region, southern Poland. The microconchids described here may represent the genus Microconchus. Most of the individuals encrust terrestrial flora and bivalve shells, and thus they certainly inhabited freshwater or, at most, brackish water environment. Similarly as the Recent polychaetes of the genus Spirorbis, the microconchids described here occur in association composed of both adult and juvenile individuals. The juveniles, however, dominate, what may indicate they have died due to some stress conditions (high rate of deposition and/or low oxygen content in the water). The microconchids are poorly-preserved. The original calcitic mineralogy of their tubes was replaced by phases similar to lead sulfide and dolomite.