In developing the new friction welding technology, the thermal elastic-plastic stress analysis by the finite element method was carried out to seek the suitable welding conditions such as the friction pressure, the fr...In developing the new friction welding technology, the thermal elastic-plastic stress analysis by the finite element method was carried out to seek the suitable welding conditions such as the friction pressure, the friction speed and the upset pressure. The results obtained are as follows： Heat transfer to the specimens and the intermediate material during friction process was made clear; The operational conditions such as the rotation number of the intermediate material and the friction pressure to reach the liquidus in the interface could be estimated; Further, as the overhang length near the interface is well related to the joint efficiency, we tried to obtain the operational conditions by numerical analysis to acquire a certain length of the overhang length near the interface.展开更多
Since 1947 （Addy） [1, 2], marine biologists have conducted experiments in order to re-establish meadows using various methods of transplant. A 27-month experiment of germinating and growing Posidonia oceanica （L.）...Since 1947 （Addy） [1, 2], marine biologists have conducted experiments in order to re-establish meadows using various methods of transplant. A 27-month experiment of germinating and growing Posidonia oceanica （L.） Delile seeds was carried out in two areas near Piombino in the Leghorn Province （Italy）. Seeds in direct contact with the sea bottom were taken from other seaside areas. The leaf growth and the percentage of well-developed plants in the study areas were calculated. The results confirm that this method appears to be a good re-establishment technique despite the problems associated with finding a large number of seeds anywhere along Mediterranean coasts.展开更多
文摘In developing the new friction welding technology, the thermal elastic-plastic stress analysis by the finite element method was carried out to seek the suitable welding conditions such as the friction pressure, the friction speed and the upset pressure. The results obtained are as follows： Heat transfer to the specimens and the intermediate material during friction process was made clear; The operational conditions such as the rotation number of the intermediate material and the friction pressure to reach the liquidus in the interface could be estimated; Further, as the overhang length near the interface is well related to the joint efficiency, we tried to obtain the operational conditions by numerical analysis to acquire a certain length of the overhang length near the interface.
文摘Since 1947 （Addy） [1, 2], marine biologists have conducted experiments in order to re-establish meadows using various methods of transplant. A 27-month experiment of germinating and growing Posidonia oceanica （L.） Delile seeds was carried out in two areas near Piombino in the Leghorn Province （Italy）. Seeds in direct contact with the sea bottom were taken from other seaside areas. The leaf growth and the percentage of well-developed plants in the study areas were calculated. The results confirm that this method appears to be a good re-establishment technique despite the problems associated with finding a large number of seeds anywhere along Mediterranean coasts.
