Side milling capability of rock cutting tools
Currently, the deviating hole drilling occupies a leading role in Russia. Directional drilling is used when the wells for oil and gas in Western Siberia, in the north of the European part, in the North Caucasus, in Tatarstan, Bashkortostan, Samara region and other areas are drilled, as our regions have a vast number of factors interfering with conventional drilling.
Leaded-tin bronze destruction mechanism
The paper is devoted to comparative analysis of the structure and mechanical properties of leaded-tin bronze with lead inclusions of various morphologies. In order to obtain lead inclusions of certain morphology, casts are cooled at certain velocities. Low cooling velocities cause spheroidizing of lead inclusions, whereas high ones give prolate inclusions with torn uneven surface.
Geologic proof on paleo-glaciation remains in Laoshan Mountain
Laoshan Mountain is the highest mountain in China coast.Various typical geomorphic features of glarosion,glacial deposition,rare glacial moraine coast and glacial moraine fans in east are well developed in Laoshan Mountain.Well preserved four glacial epochs are identified in Laoshan Mountain.In early Pleistocene,the altitude of snowline ranged from 60 m to 90 m in east.More than sixty paleo-glacial tongues were developed in Laoshan Mountain,some of them which located in east extended into the Yellow Sea.Sporopollen analysis indicates that the climate in Laoshan Mountain is very cold during the ice age.Multi-modal grain-size probability curves of the moraines are the typical characteristics of sediments deposited by glaciation.Regional landforms and climatic conditions are the key factors dominating the altitude of snowline during the ice age.