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急速凍感◆超導體驗

learnenergy2
September 19, 2024
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 急速凍感◆超導體驗

learnenergy2

September 19, 2024
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  1. 冰 Ice 0°C -78°C 乾冰 Dry Ice -196°C 液態氮 LN2

    -269°C 液態氦 LHe 這些物質的溫度? Dry ice is the solid form of carbon dioxide(二氧化碳)
  2. 當水遇上液態氮 When WATER met LN2 液態氮在常溫中會吸收熱量,迅速汽化並使周圍 溫度降低。因此使水達凝固點結冰,最終液氮消 失剩下冰晶。 Liquid Nitrogen

    will be rapidly vaporized at room temperature. It will also absorb the heat of vaporization and reduce ambient temperature, thus the WATER turns into a solid.
  3. 液態氮的應用 Used 低溫保存 遠洋漁業冷藏船注入少量液氮 進行冷卻。 Seafood is sensitive and spoils

    quickly. The high speed of snap freezing, in which the product is cooled down in a very short time to temperatures below -70°C, is usually achieved through immersion in liquid nitrogen.
  4. 液態氮的應用 Used 地面凍結 Ground freezing 含水量多、易坍陷的地帶挖掘隧道,可先用液 態氮將水凝結成冰後進行挖掘。 Pipes are run

    through the soil to be frozen, and then refrigerants are run through the pipes, freezing the soil. Frozen soil can be as hard as concrete.
  5. 超導體 superconductor 指可以在特定溫度以下,呈現電 阻為零的導體。 Superconductivity is the flow of electric

    current without resistance in certain metals, alloys, and ceramics at temperatures near absolute zero
  6. Nb3 Sn Pb 277 140 120 100 80 60 40

    20 Year 2030 2010 1990 1970 1950 1930 1910 2050 Hg Nb NbC NbN Nd-Al-Ge Nb3 Ge LaBaCuO LaSrCuO(1986) YBaCuO(2/87) BiCaSrCuO(1/88) TiCaSrCuO(2/88) HgCaBaCuO(4/93) ? TiCaBaCuO(6/91) Room temperature 1986 Bednorz ,& Müller 1913 Nobel Heike Kamerlingh Onnes 4K
  7. Nb3 Sn Pb 277 140 120 100 80 60 40

    20 Year 2030 2010 1990 1970 1950 1930 1910 2050 Hg Nb NbC NbN Nd-Al-Ge Nb3 Ge LaBaCuO LaSrCuO(1986) YBaCuO(2/87) BiCaSrCuO(1/88) TiCaSrCuO(2/88) HgCaBaCuO(4/93) ? TiCaBaCuO(6/91) Room temperature 1987 朱經武、吳茂昆發現 YBaCuO with Tc > 77K (-196 oC) -183oC 液態氮沸點-196oC -233oC Room temperature oK 77K -269oC Could it be you?
  8. 零電阻 zero-resistance 0 1 2 3 4 5 6 7

    0 40 80 120 160 200 240 280 K (溫度temperature) Ohm ( 電阻Resistance ) 超導態 (電阻為零) Critical temperature ↙超導臨界溫度(Tc)為90K(-183oC) 超導體溫度降至臨界溫度 以下,電阻完全消失,此 稱為零電阻。 BCS 超導電子對
  9. 牛頓雜誌 56期 1988年 1月號 SC Normal •Meissner effect 麥士那效應 •排斥磁力線

    •感覺到斥力 ~ 反磁 •磁力線無法進入超導體 •(反磁效應 = 排斥力) ▪ (Eddy current demonstration) 超導磁浮&磁懸浮