The traditional transformer is trending towards pocketsize and noiselessly in inverter using high-frequency link technique,but the control circuit becomes difficult to be designed.
Underground coal gasification is implemented under changefully natural environment which is difficult and complicated to execute,so scientific safety preventive measures should be adopted.
The underground diaphragm wall in Yellow River Undercrossing Project of the Middle Route in the South-to-North Water Diversion is the deepest and thickest one in China.
It was estimated that the prospect perspective were weakness in Zhidan area once, since data was narrow, and prospect is difficult for complicated landforms (vale, ridge and replat).
Abstract : It is difficulty to select and breed apomictic germplasm among diploid rices at present, but it has become a hotspot to select and breed apomictic germplasm among polyploid rices.