中文在线观看视频,九九热精品免费视频,成年人免费看黄色,成年人免费看黄色,亚洲免费在线播放视频,国产aⅴ精品久久久久久,国产精品推荐精品

All quartz products of the company are made of high-purity fused silica and processed with modern ceramic technology. The product is of high purity and corrosion resistance. The main component is SiO ? not less than 99.99%, and the content of impurities (K2O, Na2O, Fe2O3) is not more than 0.10%, with high strength and high thermal shock resistance. High density, tolerant of acid and alkali, does not contaminate raw materials at high temperatures, does not crack during feeding, and can be used continuously multiple times