r*s 发帖数: 2555 | 1 DALLAS — An ex-physician has been charged with capital murder in the
February death of a woman who was left incapacitated in 1988 after being
sexually assaulted and strangled in a case that a team of prosecutors,
investigators and victim advocates funded by a federal cold case grant
helped reinvigorate. George Guo, a former prisoner who is a registered sex
offender, was arrested Wednesday in Houston in connection to the June 1988
attack on Dr. Katherine Bascone, according to the Dallas County Di... 阅读全帖 |
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发帖数: 1 | 2 22岁曹原连发两篇《自然》:两层石墨烯叠成“魔角”可超导
微信公众号“原理”
2018-03-07 20:20
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1911年,荷兰物理学家Heike Kamerlingh Onnes 惊讶地发现,当汞被冷却至接近绝对
零度(零下273.15摄氏度)时,电子可以通行无“阻”。他将这个“零电阻状态”称为
“超导电性”。
从那之后,物理学家就不断地想要找到高温超导材料,以应用在日常生活之中。然而,
大多数材料只有在接近绝对零度时,才会转变为超导体。即使是所谓的“高温”超导体
也只是在相对意义上的:目前零电阻导电的最高温度约为-140ºC。如果有哪种材
料能够在室温下表现出超导电性,就可以为能量传输、医用扫描仪和交通领域带来革命
性的改变。
3月5日,物理学家在两篇发表在《自然》期刊的论文中指出,当两层石墨烯以一个“魔
角”扭曲在一起时,就能在零电阻下导电。更确切地说,物理学家将两层只有原子厚的
石墨烯以特别的角度堆叠在一起,当碳原子间的排列呈1.1度(这个角度就是所谓的“
魔角”)的角度偏移时,就会使材料变为超导体。尽管该系统仍然需要被冷却至绝对零
度以上1.7度,但结果表明了... 阅读全帖 |
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E******d 发帖数: 39 | 3 A few apartment complex at S. Bascon ave and union ave, Campbell, ca 95008.
All of them are close to Ebay Hamilton compus. |
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