Home%20Work%208%20(Electrode)

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Home Work 8 (Electrode)

• 6?

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Ranking of Proj.

• 2007102856 ???
• 2005200439 ???
• 2007102854 ???
• 2004200459 ???
• 2004200456 ???

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About Electrode
???? - ?? ????? ?? - NaCl ??? ??
Anode
Cathod
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About Electrode

• ?? ???
• - ??
• ??? ??? to
• ??? ?? ? - to
• ?????
• ??? ??? to
• ??? ?? ? - to

i
?? ??? ?? ?? ??? ??
Anode
Cathod
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Charge double layer
?? - ??? ?????
Halfcell potential(contact potential)
Ehd
Ehd
? ??? Charge double layer(????)??. Ehd?
Halfcell potential ??. Charge double layer?
????? ??? ???? ??? electrod circuit?? ?? ??? ???
??.
Charge double layer
????
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Charge double layer
Cd
Rs
Ehc
Rd
Ehc? ?? ? ??? Cd? ? ??
Polarizable electrode Pt, Ag, Au, Cu ?
Cd
Rs
Ehc
Capacitive
Motion artifact? ??.
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Charge double layer
Ehc? ?? ? ??? ??? Cd? ?? ??
Nonpolarizable electrode Ag AgCl ??
Calomel ??
Resistive
Motion artifact? ??.
(??? ?? ???? ??? ??? ?? ??.) (?? ??? AgCl ??? ?
???? ?? ??.)
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Charge double layer
1mV- 0mV-
501mV- 500mV-
ECG electrode circuit
DC Level ? ?? ??? Overloading? ??? ? ??. ??? HPF?
????.
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Half cell potential
Half cell potential? ? ???? ??? ??? ? ??.
??? ???? ?? Charge double layer? ??? ??? ? ??. ?
??? Half cell potential? ???? ??? ? ??. ???
electrod AgCl? little half cell potential ? ???
?? ??? electrod AgCl ? ???? ??.
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Ag-AgCl electrode
t
I
Ag
Ag
Ag
Anode
AgCl Coating
Cathod
KCl solution
??
AgCl ?? ??? I , t ? ??
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Real circuit of electrode
Sponge with NaCl
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Real circuit of electrode
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Real circuit of electrode
C
Multimeter
R
Z
Z R jX
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Real circuit of electrode
????? ?? ( )
Impedance Analyzer
Impedance Spectrum
R
0.707R
Frequancy Sweeping
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Real circuit of electrode
??
??
Resistance Reactance
Impedance
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Real circuit of electrode
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Real circuit of electrode
Cd
Cd
Rs
Rs
Rd
Rd
Rd Rs
Rs
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Real circuit of electrode
?? ???? ??? ??
Cd
Ps
Rd
??? Cd? open ?? ??? Rd Ps ? ??.
?? ????? Rs? AC? ?? Cd? short ??? ? ??? Rs? ??.
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Real circuit of electrode
Nonpolarizable electrode ? ??
Ag AgCl
Rd Rs
AgCl ?? ????
???? ?? ????? ??? ???. Resistance Electrode
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Real circuit of electrode
Polarizable electrode ? ?? (Pt ??)
Pt
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Real circuit of electrode
??? ?? ?? ?? ? ???? ??? ?? ???? ?? ???
????. ??? ?? ?? ?? ? ???? ??? ?? ???? ??
?? ??? ???. ??? ?? ?? ?? ? ???? ??? ??
???? ?? ?? ??? ???, ??? ?? ?? ?? ?
?? ????? ?? ? ?? ????. ?, ???? ???? ?? ??
???? ?? ???? ?? ?? ??? ??? ?? ????? ? ? ??. ??
??? ??? ?? ??? ?????, ???? ??? ? ????? ??? ???
??? ???? ?????? ??? ???? ???? ????. ??? ?? ???
??? ????? ??? ? ?? ???.