Recently, Professor Pan Jianwei, professor of University of Science and Technology of China, and colleagues Peng Chengzhi and Zhang Qiang, for the first time in the world, succeeded in achieving the quantum key distribution in the free space for a long time during the daytime (53.......

Recently, researcher Tang Yongbing and his research team of Functional Film Materials Research Center of Institute of Advanced Institute of Technology, Institute of Advanced Technology of Chinese Academy of Sciences successfully developed a new type of high-performance, low-cost .......

Over the years, the lighting industry has continued to be in a downturn due to the impact of the environment. When the newspaper surveyed the national lighting market, it was found that most of the city's lighting market was bleak and the transaction was bleak. Some businessmen bluntly said.......

Wit.......

• Posted on November 13, 2021

(1) Nugget layout

The layout of the ore block is divided into two types: the strike direction and the cut direction.

1 Arrange along the strike—When the ore and surrounding rock are relatively stable, when the thickness of the ore body does not exceed 10-15 meters, it.......

In pharmaceutical plants, compressed air is mainly used in filling machines in liquid preparations, granulators in a solid preparation, a granulator, a filling machine, a packaging machine, a printing machine, and an extraction tank in an extraction process, in addition to compressed air........

(1) Features:

(1) Divide the ore into a mine room and a pillar, first pick the house, then pick the column, and pick it up in two steps. The mining room is layered and recovered from the bottom up. With the upward movement of the mining face, the goaf is filled layer by layer to maintain th.......

July 21, State Grid Henan Provincial Power Company held a relay protection work conference, calling for continuously strengthening team building, continuing to strengthen the entire process of management, and effectively enhance the relay protection and grid intrinsically safe le.......

Drought disaster is one of the most serious natural disasters in agricultural production. In recent years, with the continuous changes in the climate, the area of ​​agricultural disasters has also been expanding year by year, and the frequency of occurrence has been.......