日韩午夜精品视频,欧美私密网站,国产一区二区三区四区,国产主播一区二区三区四区

--- SEARCH ---
WEATHER
CHINA
INTERNATIONAL
BUSINESS
CULTURE
GOVERNMENT
SCI-TECH
ENVIRONMENT
SPORTS
LIFE
PEOPLE
TRAVEL
WEEKLY REVIEW
Learning Chinese
Learn to Cook Chinese Dishes
Exchange Rates
Hotel Service
China Calendar


Hot Links
China Development Gateway
Chinese Embassies

Manufacturers, Exporters, Wholesalers - Global trade starts here.

The Alloy Ingredients of the Yongle Bell

The fine fluidity in the process of casting had a direct bearing on the surface effects of the cast. In 1993, in cooperation with No. 621 Research Institute of the Ministry of Aerospace Industry, we made another test of the alloy ingredients of the Yongle Bell, including the trace elements. We obtained new data. For the first time we found that besides copper, tin, lead, zinc, aluminum, iron and magnesium, the big bell contained gold and silver. The gold was good for resisting rust and corrosion, and the silver enhanced the fluidity of casting fluid.

Print This Page | Email This Page
About Us SiteMap Feedback
Copyright © China Internet Information Center. All Rights Reserved
E-mail: webmaster@china.org.cn Tel: 86-10-68326688
主站蜘蛛池模板: 化隆| 滨海县| 富锦市| 花莲县| 泸定县| 靖边县| 金寨县| 名山县| 贵南县| 宜春市| 南木林县| 靖宇县| 阳山县| 会泽县| 广河县| 徐州市| 汽车| 天祝| 陆川县| 南安市| 浮山县| 呈贡县| 永泰县| 汾西县| 凤凰县| 乌什县| 菏泽市| 沐川县| 乌兰察布市| 开封市| 常宁市| 汾阳市| 丰镇市| 安丘市| 安阳县| 东山县| 延边| 永城市| 阳谷县| 北辰区| 河曲县|