XAFS

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XAFS

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1. XAFS??? ????????????? ????????? ?? ??

2. XAFS??????? ???·XAFS??? Ti K?(4.96keV) Cs LIII?(5.01keV) Ba LIII?(5.24keV) k~8.6A-1 ????????

3. ??? · XAFS???????? ???????????????????????????????????? I0 = IIN {1-exp(-m0x0)} I = (IIN-I0) exp (-mSX) mt = ln(I0/I) = ln {1-exp(-m0x0)} + m0x0 +mSX ???????????????????

4. XAFS??c

5. ??????? I0????? (mx)0 = 0.245 ????? mX=2.55 ?S/N??? S/N = 0.556 DmA/m (IIN)1/2 DmA : XAFS???? m : ?????? IIN : ????? I????? 0.9~<1

6. X????????? ????????S/N???????yes ??????????????????????(KMnO4????…) ?????????????S/N???????(?????????…)

7. ??????? ????????? · ???????mt?????4???? ????????ecl<4??? ?????????( Dmt)????????? (<2) Dmt~3 ???? 2V ? ???? 0.1V ????dynamic range ????????????????????

8. ??????? I/I0 = exp(-mMrx) = exp(-mx) mM : ?????? (cm2/g) m : ????? (cm-1) r : ?? (gcm-3) x : ????? (cm) mM = S mMi Wi =Cl3?Dl4 0.1mol dm-3?Cu?????

9. ????? ????????????? ????

10. X??????????

11. ??? 2d sin q = nl (n = 1, 2, 3…) ?????? ?????? a:1×10-1?b: 2×10-3?c: 6×10-5 <10-4 ???? a: Ti(5mm) + Al(30mm) b,c : Ti(5mm) + Al(60mm)

12. glitch ?????????????I0???????????? · ??????????????????????? · ???????????? · ???????? · ????? ???????????? ??????????

13. ?????(1) ?????? ???

14. ?????(2) ?????? ???

15. ???????

16. ??????????? ?????????????????? ????10-4???????? ????????X?????????? ????????????????

17. ?????? ??? ?????? ?????? wt%

18. ??? ??X?????X???????????? ??? ???????????? ??????????

19. ???????? [??] ????????????????? ????? eW/8p > mA/mT e~0.5 (Ga)? W/4p ~0.15 0.3wt%?Cu/SiO2 0.02 mol dm -3?Cu aq.

20. ???(??????)

21. ??XAFS???? Lytle detector

22. ??????(SSD) ?????????????? ???????? S/N = S/(S+B)1/2, S/B~1/200 ??X????X???????

23. ???????(CEY)

24. ?X??????? ??????? ??? : ???????????????? ??????????Photo Diode ??? : ????????S/B??? Photo Diode?PC?SSD ???????? ?????(AEY/PEY/TEY):???????????? CEM?EM???????

25. ?X???????

26. ????CEY?

27. ???? ?????? ?X????? · ???/He????/??? · ???/???(~10K) ????????? ??(?????????????) ??????(???) ???? ???????(SPring-8) ????? ?????? ????(??He) ???(?????????????DAC????..) ??????/??????? in -situ??? ??????(s~ms)

28. XAFS???? In one trip to the synchrotron we collected more and better data in three days than in the previous ten years.(F.W. Lytle, J. Synchrotron Rad., 6, 123 (1999)) ????????

29. ?????

30. ???????

31. ???????XAFS??

32. ?????????

33. ?????? ????? ????? ????? ????? ??????????

34. ??????? ????(???????) ???? ???? ??? ???????

35. ?????? Bragg?? 2d sin q = nl n=1 ??? n>1 ??????? ??????????? E l = hc = 12398.52 [eV A]

36. ???????? ????????

37. ??? ??/??????? 1m????????? ??:Si???????????? ??:Rh?Pt?Ni... ????? ????????????

38. ???·??? ??? X?????????? ??????? ?????????????????????

39. Photon Factory

41. ????XAFS?? Advantage 1. ??????????????(?????????) 2. ???????? 3. ???? 4. ????????????? 5. ??? Disadvantage 1. X???????????????? 2. ??????????? 3. ????? 4. ??? 5. ?????????? [??????XAFS???] ·1920??????????????????????????????????????????????????????1970???????????????????????XAFS?????????????????????????????????????????in-laboratory????????XAFS????????????????????????? ·Photon Factory?Spring-8??????????????????????????????????????????????????????????????????????????????XAFS????????? ·???????????????????????????????????????????????????????????????????????????????????????????????XAFS?????????????????????????????????? [??????XAFS???] ·1920??????????????????????????????????????????????????????1970???????????????????????XAFS?????????????????????????????????????????in-laboratory????????XAFS????????????????????????? ·Photon Factory?Spring-8??????????????????????????????????????????????????????????????????????????????XAFS????????? ·???????????????????????????????????????????????????????????????????????????????????????????????XAFS??????????????????????????????????

42. [XAFS??????] ·??????????????????????????????????????????????????? ·??????????????????????????????????????????????????????????????????????????????????? [XAFS??????] ·??????????????????????????????????????????????????? ·???????????????????????????????????????????????????????????????????????????????????

43. ??XAFS????? ??????? 5 ~ 25keV ????????????????????(>20keV)???????????????? ???? 1??~1? ??????1?????????????????????????????????????????1??????????????????????????????? ???? 0.1wt%??? ??????????????????????????????????? ?????5mM?FeCl3????XAFS?????????????

44. ???????? ???????? ????????

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