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Episode 25Open the course of "Gem Processing Technology", It is found that it is based on "Gem Processing Technology" written by Professor Liu Ziqiang of Jewelry Department of Jinling Institute of Science and Technology. Including six aspects of knowledge-a preliminary understanding of some gemstone raw materials, Understand the names, characteristics and development history of different gemstone cut styles, understand some basic equipment and accessories for gemstone processing, understand the processing principles and technological methods of gemstones, see the processing process of standard round polyhedral styles, and learn the processing quality evaluation of gemstones (including jadeite).Private static ConnectionPool instance = null;< h2 > This is a heading 6. The output is generally 300 kg, which is as high as 500-600 kg. The output in the second year will be slightly higher. Because of the original shrimp breeding, a pair of parent shrimps can breed hundreds of shrimps a year. In the second year, there is generally no need to replenish seedlings. If the first year is overworked, it is recommended to replenish part in March-April of the second year.Extinguish Application Layer Attacks Internally