Wednesday, November 26, 2014

公开密钥加密


Just two lines by Francesca Lidia Ortenzi


Levon Grigori Aronian – Hikaru Nakamura
Showdown in Saint Louis; match game 2; Saint Louis, November 22, 2014
Catalan Opening E05

1. c4 e6 2. g3 d5 3. Bg2 Nf6 4. Nf3 Be7 5. 0-0 0-0 6. d4 dxc4 7. Ne5 Nc6 8. Bxc6 bxc6 9. Nxc6 Qe8 10. Nxe7+ Qxe7 11. Na3 c5 12. dxc5 Qxc5 13. Be3 Qb4 14. Qc1. For 14. Qd4 Ba6 see 居文君 (Jū Wénjūn) – 赵雪 (Zhào Xuě), FIDE Women’s Grand Prix, Sharjah 2014. 14. ... Ba6 15. Bd4 Rfd8 16. Rd1 Rac8 17. Qc3 Qa4. Aronian then said he did not expect this move, after which White gets nothing. 18. Qc2 Qxc2 19. Nxc2 c3! Elegant and dynamic play by Nakamura! 20. Bxc3 Rxd1+ 21. Rxd1 Bxe2 22. Re1 Bc4. Even stronger looks 22. ... Bf3!, but also the text is sufficient to survive. 23. Ne3 Nd5 24. Nxc4 Rxc4 25. Bd2 Kf8 26. Rc1 Rxc1+ 27. Bxc1. Ulhumbrus says: “White has a powerful Bishop against a Knight and an asymmetrical Pawn structure which includes a Queenside Pawn majority”. Not so much, but it's better than nothing. 27. ... Ke7 28. Kf1 e5 29. Ke2 e4 30. Kd2 f5 31. Kc2 Nb4+?! More to the point was 31. ... Kd6 32. Kb3 Kc5 with roughly equal chances. 32. Kb3 Nd3 33. Be3 a6 34. Kc3 Kd6 35. h4. Now Black’s Kingside Pawn majority is stuck, whereas White’s Queenside Pawn majority is not. As originally noted by Ulhumbrus the endgame is reminiscent of a vintage background Capablanca – Corzo, Habana 1901, match game 9. 35. ... g6 36. b4 Kd5. The computer move 36. ... Kc6 could perhaps work better, but, objectively speaking, it has anything human. 37. a4 Ne5 38. b5


38. ... a5? A serious mistake instead of which he should have played 38. ... axb5 39. axb5 Nd3! after which the smooth 40. Kb3 (intending Kb3-a4-a5) is nullified by 40. ... h6! 41. Kc3 g5 42. b6 Kc6 43. hxg5 hxg5=. 39. Bb6 Nc4 40. Bd8! Kc5 41. Bc7! h5 42. Kc2 Kd5 43. Kb3 Nd2+ 44. Kc3 e3. On 44. ... Nb1+ 45. Kc2 Na3+ 46. Kb3 Nc4 47. b6 simply wins. 45. fxe3 Ne4+ 46. Kb2 Nc5 47. Bxa5 Nxa4+ 48. Ka3 Nc5 49. Bb4 Nb7 50. Ka4 1 : 0. Black is in Zugzwang. If the Knight moves, White’s King advances and soon “Queens” the passed Pawn. If instead the King moves, White plays b5-b6 and the King breaks in via the b5-square.

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