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我国首建纳米级角度国家一级标准物质
标准物质研制单位同济大学相关专家介绍,二维铬纳米栅格标准物质突破性地采用分步沉积原子光刻技术,制备难度较大,可直接溯源到自然界量子化物理常数(铬原子跃迁频率),角度绝对准确性在0.001°量级,相当于把一个蛋糕按扇形均分成三十六万份。
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今日热点
Republicans win the House
Lawyers seek to quit case
FBI raids Coplan's home
Ban on executives upheld
Declines WH invitation
Reveals cancer diagnosis
Died of septic shock
Threatened by LSU student?
Gaetz resigns from Congress
‘I was not paid a dime’
Gabbard picked as DNI
Recuses self from AZ case
Wins GOP nod for speaker
Pulled from lunch program
US strikes Iran-linked group
Amtrak service disrupted
Bitcoin rises above $90K
To face US antitrust trial
Starts issuing layoff notices
Recalling pickups, SUVs
Freevee to shut down
US govt. worker charged
How to watch fight?
2,400+ Cybertrucks recalled
Trump, Biden meet at WH
Russia attacks Kyiv
Former solicitor general dies
Next Senate majority leader
US missile base in Poland
US streamer indicted in SK
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