1536:
1090:
366:
spectrum of a substance is specific to the substance - and NQR spectrum is a so called "chemical fingerprint." Because NQR frequencies are not chosen by the experimenter, they can be difficult to find making NQR a technically difficult technique to carry out. Since NQR is done in an environment without a static (or DC) magnetic field, it is sometimes called "
365:
just as the NMR experimenter is free to choose the Larmor frequency by adjusting the magnetic field. However, in solids, the strength of the EFG is many kV/m^2, making the application of EFG's for NQR in the manner that external magnetic fields are chosen for NMR impractical. Consequently, the NQR
73:
at which transitions occur is unique for a given substance. A particular NQR frequency in a compound or crystal is proportional to the product of the nuclear quadrupole moment, a property of the nucleus, and the EFG in the neighborhood of the nucleus. It is this product which is termed the nuclear
82:
Any nucleus with more than one unpaired nuclear particle (protons or neutrons) will have a charge distribution which results in an electric quadrupole moment. Allowed nuclear energy levels are shifted unequally due to the interaction of the nuclear charge with an electric field gradient supplied by
1797:
There are several research groups around the world currently working on ways to use NQR to detect explosives. Units designed to detect landmines and explosives concealed in luggage have been tested. A detection system consists of a radio frequency (RF) power source, a coil to produce the magnetic
83:
the non-uniform distribution of electron density (e.g. from bonding electrons) and/or surrounding ions. As in the case of NMR, irradiation of the nucleus with a burst of RF electromagnetic radiation may result in absorption of some energy by the nucleus which can be viewed as a
74:
quadrupole coupling constant for a given isotope in a material and can be found in tables of known NQR transitions. In NMR, an analogous but not identical phenomenon is the coupling constant, which is also the result of an internuclear interaction between nuclei in the analyte.
1531:{\displaystyle U=-{\frac {1}{2}}\int _{\mathcal {D}}d^{3}r\rho ({\textbf {r}})\left=-{\frac {1}{2}}\int _{\mathcal {D}}d^{3}r\rho ({\textbf {r}})\left=-{\frac {1}{2}}\left({\frac {\partial E_{i}}{\partial x_{i}}}\right){\Bigg \vert }_{0}\cdot \int _{\mathcal {D}}d^{3}r\left}
87:
of the quadrupole energy level. Unlike the NMR case, NQR absorption takes place in the absence of an external magnetic field. Application of an external static field to a quadrupolar nucleus splits the quadrupole levels by the energy predicted from the
1812:
in realtime. This particular technique allows local or remote monitoring of the extraction process, calculation of the well's remaining capacity and the water/detergents ratio the input pump must send to efficiently extract oil.
652:
479:. This potential may be produced by the electrons as stated above, whose probability distribution might be non-isotropic in general. The potential energy in this system equals to the integral over the charge distribution
221:. The nuclear quadrupole moment is associated with non-spherical nuclear charge distributions. As such it is a measure of the degree to which the nuclear charge distribution deviates from that of a sphere; that is, the
233:
created by the electronic structure of its environment. The NQR transition frequencies are proportional to the product of the electric quadrupole moment of the nucleus and a measure of the strength of the local EFG:
1788:
1620:
909:
303:
1027:
1805:
claimed to exploit NQR to detect explosives but in fact could do no such thing. Nonetheless, the device was successfully sold for millions to dozens of countries, including the government of Iraq.
1029:, the first derivatives can also be neglected. One is therefore left with all nine combinations of second derivatives. However if one deals with a homogeneous oblate or prolate nucleus the matrix
149:
510:
444:
543:
477:
1538:
The remaining terms in the integral are related to the charge distribution and hence the quadrupole moment. The formula can be simplified even further by introducing the
567:
363:
96:
in solids when performed at varying temperature. Due to symmetry, the shifts become averaged to zero in the liquid phase, so NQR spectra can only be measured for solids.
967:
411:
574:
172:
333:
1720:
1083:
61:. Unlike NMR, NQR is applicable only to solids and not liquids, because in liquids the electric field gradient at the nucleus averages to zero (the EFG tensor has
1650:
1057:
1688:
1085:
vanish. This leads to a simplification because the equation for the potential energy now contains only the second derivatives in respect to the same variable:
940:
196:
1727:
667:
108:≥ 1/2 have a magnetic dipole moment so that their energies are split by a magnetic field, allowing resonance absorption of energy related to the
1919:
1544:
240:
1897:
1798:
excitation field and a detector circuit which monitors for a RF NQR response coming from the explosive component of the object.
972:
1691:
1867:
92:. The technique is very sensitive to the nature and symmetry of the bonding around the nucleus. It can characterize
1816:
Due to the strong temperature dependence of the NQR frequency, it can be used as a precise temperature sensor with
38:
1871:
229:
shape of the nucleus. NQR is a direct observation of the interaction of the quadrupole moment with the local
1539:
230:
943:
118:
62:
65:
zero). Because the EFG at the location of a nucleus in a given substance is determined primarily by the
1653:
482:
416:
659:
84:
58:
515:
449:
341:
175:
548:
948:
392:
1893:
1817:
109:
66:
54:
34:
157:
1850:
93:
311:
662:
in cartesian coordinates (note that the equations below use the
Einstein sum-convention):
1696:
1062:
17:
1625:
1032:
308:
where q is related to the largest principal component of the EFG tensor at the nucleus.
1659:
367:
181:
105:
50:
46:
42:
916:
1913:
1875:
655:
338:
In principle, the NQR experimenter could apply a specified EFG in order to influence
89:
30:
647:{\displaystyle U=-\int _{\mathcal {D}}d^{3}r\rho ({\textbf {r}})V({\textbf {r}})}
1838:
942:
will not be relevant and can therefore be omitted. Since nuclei do not have an
1808:
Another practical use for NQR is measuring the water/gas/oil coming out of an
218:
41:). Unlike NMR, NQR transitions of nuclei can be detected in the absence of a
206:
70:
1809:
226:
222:
210:
202:
658:
at the center of the considered nucleus. This method corresponds to the
1802:
1622:, choosing the z-axis as the one with the maximal principal component
1854:
370:". Many NQR transition frequencies depend strongly upon temperature.
214:
1783:{\displaystyle \nu ={\frac {1}{2}}\left({\frac {e^{2}qQ}{h}}\right)}
1615:{\textstyle V_{ii}={\frac {\partial ^{2}V}{\partial x_{i}^{2}}}=eq}
904:{\displaystyle V({\textbf {r}})=V(0)+\left+{\frac {1}{2}}\left+...}
198:
is the (normally applied) magnetic field external to the nucleus.
69:
involved in the particular bond with other nearby nuclei, the NQR
298:{\displaystyle \omega _{Q}\sim {\frac {e^{2}Qq}{\hbar }}=C_{q}}
1465:
1265:
1119:
593:
554:
1022:{\textstyle {\textbf {E}}=-\mathrm {grad} V({\textbf {r}})}
49:". The NQR resonance is mediated by the interaction of the
45:, and for this reason NQR spectroscopy is referred to as "
1699:
1662:
1628:
1547:
1065:
1035:
975:
951:
919:
551:
518:
485:
452:
419:
395:
1730:
1093:
670:
577:
389:
Consider a nucleus with a non-zero quadrupole moment
344:
314:
243:
184:
160:
121:
1656:
to obtain the proportionality written above. For an
335:
is referred to as the quadrupole coupling constant.
1782:
1714:
1682:
1644:
1614:
1530:
1077:
1051:
1021:
961:
934:
903:
646:
561:
537:
504:
471:
438:
405:
357:
327:
297:
201:In the case of NQR, nuclei with spin ≥ 1, such as
190:
166:
143:
1445:
1350:
1209:
850:
748:
37:technique related to nuclear magnetic resonance (
969:, which would interact with the electric field
8:
1892:. London: Peter Peregrinus Ltd. p. 48.
1874:. In Jacqueline MacDonald, J. R. Lockwood:
1839:"Nuclear Quadrupole Resonance Spectroscopy"
1878:. Report MR-1608, Rand Corporation, 2003.
1758:
1751:
1737:
1729:
1698:
1672:
1661:
1633:
1627:
1594:
1589:
1571:
1564:
1552:
1546:
1517:
1512:
1496:
1495:
1475:
1464:
1463:
1450:
1444:
1443:
1429:
1414:
1404:
1390:
1373:
1368:
1355:
1349:
1348:
1334:
1319:
1309:
1291:
1290:
1275:
1264:
1263:
1249:
1232:
1227:
1214:
1208:
1207:
1193:
1188:
1170:
1163:
1145:
1144:
1129:
1118:
1117:
1103:
1092:
1064:
1040:
1034:
1010:
1009:
989:
977:
976:
974:
953:
952:
950:
918:
878:
868:
855:
849:
848:
834:
824:
806:
799:
780:
766:
753:
747:
746:
732:
714:
678:
677:
669:
635:
634:
619:
618:
603:
592:
591:
576:
553:
552:
550:
526:
525:
517:
493:
492:
484:
460:
459:
451:
427:
426:
418:
397:
396:
394:
349:
343:
319:
313:
289:
264:
257:
248:
242:
183:
159:
126:
120:
1868:Appendix K: Nuclear quadrupole resonance
1829:
277:
1890:Temperature measurement & control
446:, which is surrounded by a potential
7:
144:{\displaystyle \omega _{L}=\gamma B}
1876:Alternatives for Landmine Detection
1497:
1292:
1146:
1059:will be diagonal and elements with
1011:
978:
954:
679:
636:
620:
527:
494:
461:
428:
398:
1582:
1568:
1422:
1407:
1327:
1312:
1181:
1167:
999:
996:
993:
990:
817:
803:
725:
717:
25:
654:One can write the potential as a
505:{\textstyle \rho ({\textbf {r}})}
439:{\textstyle \rho ({\textbf {r}})}
374:Derivation of resonance frequency
1837:Smith, J. A. S. (January 1971).
1803:fake device known as the ADE 651
104:In the case of NMR, nuclei with
1502:
1492:
1297:
1287:
1151:
1141:
1016:
1006:
929:
923:
699:
693:
684:
674:
641:
631:
625:
615:
532:
522:
499:
489:
466:
456:
433:
423:
1:
1843:Journal of Chemical Education
1690:nucleus one obtains with the
538:{\textstyle V({\textbf {r}})}
472:{\textstyle V({\textbf {r}})}
231:electric field gradient (EFG)
28:Nuclear quadrupole resonance
562:{\textstyle {\mathcal {D}}}
358:{\displaystyle \omega _{Q}}
1936:
1920:Nuclear magnetic resonance
962:{\textstyle {\textbf {p}}}
406:{\textstyle {\textbf {Q}}}
219:electric quadrupole moment
1872:Naval Research Laboratory
1692:frequency-energy relation
913:The first term involving
18:Nuclear quadrupole moment
1888:Leigh, James R. (1988).
1870:, by Allen N. Garroway,
53:gradient (EFG) with the
1820:on the order of 10 °C.
1540:electric field gradient
167:{\displaystyle \gamma }
1784:
1716:
1684:
1646:
1616:
1532:
1079:
1053:
1023:
963:
944:electric dipole moment
936:
905:
648:
563:
539:
506:
473:
440:
407:
359:
329:
299:
192:
168:
145:
1785:
1717:
1685:
1647:
1617:
1533:
1080:
1054:
1024:
964:
937:
906:
649:
564:
540:
507:
474:
441:
408:
360:
330:
328:{\displaystyle C_{q}}
300:
193:
169:
146:
1728:
1715:{\textstyle E=h\nu }
1697:
1660:
1626:
1545:
1091:
1078:{\textstyle i\neq j}
1063:
1033:
973:
949:
917:
668:
575:
549:
516:
483:
450:
417:
393:
342:
312:
241:
182:
158:
119:
1645:{\textstyle Q_{zz}}
1599:
1522:
1378:
1237:
1198:
1052:{\textstyle Q_{ij}}
660:multipole expansion
413:and charge density
59:charge distribution
1780:
1712:
1683:{\textstyle I=3/2}
1680:
1642:
1612:
1585:
1528:
1508:
1364:
1223:
1184:
1075:
1049:
1019:
959:
932:
901:
644:
559:
535:
512:and the potential
502:
469:
436:
403:
355:
325:
295:
188:
176:gyromagnetic ratio
164:
141:
90:Zeeman interaction
1774:
1745:
1601:
1499:
1436:
1398:
1341:
1294:
1257:
1200:
1148:
1111:
1013:
980:
956:
935:{\textstyle V(0)}
841:
788:
739:
681:
638:
622:
529:
496:
463:
430:
400:
280:
191:{\displaystyle B}
94:phase transitions
67:valence electrons
55:quadrupole moment
35:chemical analysis
16:(Redirected from
1927:
1904:
1903:
1885:
1879:
1865:
1859:
1858:
1855:10.1021/ed048p39
1834:
1789:
1787:
1786:
1781:
1779:
1775:
1770:
1763:
1762:
1752:
1746:
1738:
1721:
1719:
1718:
1713:
1689:
1687:
1686:
1681:
1676:
1654:Laplace equation
1651:
1649:
1648:
1643:
1641:
1640:
1621:
1619:
1618:
1613:
1602:
1600:
1598:
1593:
1580:
1576:
1575:
1565:
1560:
1559:
1537:
1535:
1534:
1529:
1527:
1523:
1521:
1516:
1501:
1500:
1480:
1479:
1470:
1469:
1468:
1455:
1454:
1449:
1448:
1441:
1437:
1435:
1434:
1433:
1420:
1419:
1418:
1405:
1399:
1391:
1383:
1379:
1377:
1372:
1360:
1359:
1354:
1353:
1346:
1342:
1340:
1339:
1338:
1325:
1324:
1323:
1310:
1296:
1295:
1280:
1279:
1270:
1269:
1268:
1258:
1250:
1242:
1238:
1236:
1231:
1219:
1218:
1213:
1212:
1205:
1201:
1199:
1197:
1192:
1179:
1175:
1174:
1164:
1150:
1149:
1134:
1133:
1124:
1123:
1122:
1112:
1104:
1084:
1082:
1081:
1076:
1058:
1056:
1055:
1050:
1048:
1047:
1028:
1026:
1025:
1020:
1015:
1014:
1002:
982:
981:
968:
966:
965:
960:
958:
957:
941:
939:
938:
933:
910:
908:
907:
902:
888:
884:
883:
882:
873:
872:
860:
859:
854:
853:
846:
842:
840:
839:
838:
829:
828:
815:
811:
810:
800:
789:
781:
776:
772:
771:
770:
758:
757:
752:
751:
744:
740:
738:
737:
736:
723:
715:
683:
682:
656:Taylor-expansion
653:
651:
650:
645:
640:
639:
624:
623:
608:
607:
598:
597:
596:
568:
566:
565:
560:
558:
557:
545:within a domain
544:
542:
541:
536:
531:
530:
511:
509:
508:
503:
498:
497:
478:
476:
475:
470:
465:
464:
445:
443:
442:
437:
432:
431:
412:
410:
409:
404:
402:
401:
386:
385:
381:
364:
362:
361:
356:
354:
353:
334:
332:
331:
326:
324:
323:
304:
302:
301:
296:
294:
293:
281:
276:
269:
268:
258:
253:
252:
197:
195:
194:
189:
173:
171:
170:
165:
150:
148:
147:
142:
131:
130:
110:Larmor frequency
100:Analogy with NMR
21:
1935:
1934:
1930:
1929:
1928:
1926:
1925:
1924:
1910:
1909:
1908:
1907:
1900:
1887:
1886:
1882:
1866:
1862:
1836:
1835:
1831:
1826:
1795:
1754:
1753:
1747:
1726:
1725:
1695:
1694:
1658:
1657:
1629:
1624:
1623:
1581:
1567:
1566:
1548:
1543:
1542:
1488:
1484:
1471:
1459:
1442:
1425:
1421:
1410:
1406:
1400:
1347:
1330:
1326:
1315:
1311:
1305:
1304:
1300:
1271:
1259:
1206:
1180:
1166:
1165:
1159:
1158:
1154:
1125:
1113:
1089:
1088:
1061:
1060:
1036:
1031:
1030:
971:
970:
947:
946:
915:
914:
874:
864:
847:
830:
820:
816:
802:
801:
795:
794:
790:
762:
745:
728:
724:
716:
710:
709:
705:
666:
665:
599:
587:
573:
572:
547:
546:
514:
513:
481:
480:
448:
447:
415:
414:
391:
390:
387:
383:
379:
377:
376:
345:
340:
339:
315:
310:
309:
306:
285:
260:
259:
244:
239:
238:
217:, also have an
180:
179:
156:
155:
152:
122:
117:
116:
102:
80:
57:of the nuclear
23:
22:
15:
12:
11:
5:
1933:
1931:
1923:
1922:
1912:
1911:
1906:
1905:
1898:
1880:
1860:
1828:
1827:
1825:
1822:
1794:
1791:
1778:
1773:
1769:
1766:
1761:
1757:
1750:
1744:
1741:
1736:
1733:
1711:
1708:
1705:
1702:
1679:
1675:
1671:
1668:
1665:
1652:and using the
1639:
1636:
1632:
1611:
1608:
1605:
1597:
1592:
1588:
1584:
1579:
1574:
1570:
1563:
1558:
1555:
1551:
1526:
1520:
1515:
1511:
1507:
1504:
1494:
1491:
1487:
1483:
1478:
1474:
1467:
1462:
1458:
1453:
1447:
1440:
1432:
1428:
1424:
1417:
1413:
1409:
1403:
1397:
1394:
1389:
1386:
1382:
1376:
1371:
1367:
1363:
1358:
1352:
1345:
1337:
1333:
1329:
1322:
1318:
1314:
1308:
1303:
1299:
1289:
1286:
1283:
1278:
1274:
1267:
1262:
1256:
1253:
1248:
1245:
1241:
1235:
1230:
1226:
1222:
1217:
1211:
1204:
1196:
1191:
1187:
1183:
1178:
1173:
1169:
1162:
1157:
1153:
1143:
1140:
1137:
1132:
1128:
1121:
1116:
1110:
1107:
1102:
1099:
1096:
1074:
1071:
1068:
1046:
1043:
1039:
1018:
1008:
1005:
1001:
998:
995:
992:
988:
985:
931:
928:
925:
922:
900:
897:
894:
891:
887:
881:
877:
871:
867:
863:
858:
852:
845:
837:
833:
827:
823:
819:
814:
809:
805:
798:
793:
787:
784:
779:
775:
769:
765:
761:
756:
750:
743:
735:
731:
727:
722:
719:
713:
708:
704:
701:
698:
695:
692:
689:
686:
676:
673:
643:
633:
630:
627:
617:
614:
611:
606:
602:
595:
590:
586:
583:
580:
556:
534:
524:
521:
501:
491:
488:
468:
458:
455:
435:
425:
422:
375:
372:
368:zero field NMR
352:
348:
322:
318:
292:
288:
284:
279:
275:
272:
267:
263:
256:
251:
247:
236:
187:
163:
140:
137:
134:
129:
125:
114:
101:
98:
79:
76:
51:electric field
47:zero Field NMR
43:magnetic field
24:
14:
13:
10:
9:
6:
4:
3:
2:
1932:
1921:
1918:
1917:
1915:
1901:
1899:0-86341-111-8
1895:
1891:
1884:
1881:
1877:
1873:
1869:
1864:
1861:
1856:
1852:
1848:
1844:
1840:
1833:
1830:
1823:
1821:
1819:
1814:
1811:
1806:
1804:
1799:
1792:
1790:
1776:
1771:
1767:
1764:
1759:
1755:
1748:
1742:
1739:
1734:
1731:
1723:
1709:
1706:
1703:
1700:
1693:
1677:
1673:
1669:
1666:
1663:
1655:
1637:
1634:
1630:
1609:
1606:
1603:
1595:
1590:
1586:
1577:
1572:
1561:
1556:
1553:
1549:
1541:
1524:
1518:
1513:
1509:
1505:
1489:
1485:
1481:
1476:
1472:
1460:
1456:
1451:
1438:
1430:
1426:
1415:
1411:
1401:
1395:
1392:
1387:
1384:
1380:
1374:
1369:
1365:
1361:
1356:
1343:
1335:
1331:
1320:
1316:
1306:
1301:
1284:
1281:
1276:
1272:
1260:
1254:
1251:
1246:
1243:
1239:
1233:
1228:
1224:
1220:
1215:
1202:
1194:
1189:
1185:
1176:
1171:
1160:
1155:
1138:
1135:
1130:
1126:
1114:
1108:
1105:
1100:
1097:
1094:
1086:
1072:
1069:
1066:
1044:
1041:
1037:
1003:
986:
983:
945:
926:
920:
911:
898:
895:
892:
889:
885:
879:
875:
869:
865:
861:
856:
843:
835:
831:
825:
821:
812:
807:
796:
791:
785:
782:
777:
773:
767:
763:
759:
754:
741:
733:
729:
720:
711:
706:
702:
696:
690:
687:
671:
663:
661:
657:
628:
612:
609:
604:
600:
588:
584:
581:
578:
570:
519:
486:
453:
420:
382:
373:
371:
369:
350:
346:
336:
320:
316:
305:
290:
286:
282:
273:
270:
265:
261:
254:
249:
245:
235:
232:
228:
224:
220:
216:
212:
208:
204:
199:
185:
177:
161:
151:
138:
135:
132:
127:
123:
113:
111:
107:
99:
97:
95:
91:
86:
77:
75:
72:
68:
64:
60:
56:
52:
48:
44:
40:
36:
32:
29:
19:
1889:
1883:
1863:
1846:
1842:
1832:
1815:
1807:
1800:
1796:
1793:Applications
1724:
1087:
912:
664:
571:
388:
337:
307:
237:
200:
153:
115:
103:
85:perturbation
81:
33:or NQR is a
31:spectroscopy
27:
26:
1824:References
1818:resolution
1849:: 39–41.
1732:ν
1710:ν
1583:∂
1569:∂
1506:⋅
1490:ρ
1461:∫
1457:⋅
1423:∂
1408:∂
1388:−
1362:⋅
1328:∂
1313:∂
1285:ρ
1261:∫
1247:−
1221:⋅
1182:∂
1168:∂
1139:ρ
1115:∫
1101:−
1070:≠
987:−
862:⋅
818:∂
804:∂
760:⋅
726:∂
718:∂
613:ρ
589:∫
585:−
487:ρ
421:ρ
347:ω
278:ℏ
255:∼
246:ω
162:γ
136:γ
124:ω
78:Principle
71:frequency
1914:Category
1810:oil well
223:prolate
174:is the
1896:
378:": -->
227:oblate
154:where
63:trace
1894:ISBN
380:edit
213:and
178:and
106:spin
1851:doi
225:or
39:NMR
1916::
1847:48
1845:.
1841:.
1801:A
1722::
569::
215:Cu
211:Cl
209:,
205:,
112::
1902:.
1857:.
1853::
1777:)
1772:h
1768:Q
1765:q
1760:2
1756:e
1749:(
1743:2
1740:1
1735:=
1707:h
1704:=
1701:E
1678:2
1674:/
1670:3
1667:=
1664:I
1638:z
1635:z
1631:Q
1610:q
1607:e
1604:=
1596:2
1591:i
1587:x
1578:V
1573:2
1562:=
1557:i
1554:i
1550:V
1525:]
1519:2
1514:i
1510:x
1503:)
1498:r
1493:(
1486:[
1482:r
1477:3
1473:d
1466:D
1452:0
1446:|
1439:)
1431:i
1427:x
1416:i
1412:E
1402:(
1396:2
1393:1
1385:=
1381:]
1375:2
1370:i
1366:x
1357:0
1351:|
1344:)
1336:i
1332:x
1321:i
1317:E
1307:(
1302:[
1298:)
1293:r
1288:(
1282:r
1277:3
1273:d
1266:D
1255:2
1252:1
1244:=
1240:]
1234:2
1229:i
1225:x
1216:0
1210:|
1203:)
1195:2
1190:i
1186:x
1177:V
1172:2
1161:(
1156:[
1152:)
1147:r
1142:(
1136:r
1131:3
1127:d
1120:D
1109:2
1106:1
1098:=
1095:U
1073:j
1067:i
1045:j
1042:i
1038:Q
1017:)
1012:r
1007:(
1004:V
1000:d
997:a
994:r
991:g
984:=
979:E
955:p
930:)
927:0
924:(
921:V
899:.
896:.
893:.
890:+
886:]
880:j
876:x
870:i
866:x
857:0
851:|
844:)
836:j
832:x
826:i
822:x
813:V
808:2
797:(
792:[
786:2
783:1
778:+
774:]
768:i
764:x
755:0
749:|
742:)
734:i
730:x
721:V
712:(
707:[
703:+
700:)
697:0
694:(
691:V
688:=
685:)
680:r
675:(
672:V
642:)
637:r
632:(
629:V
626:)
621:r
616:(
610:r
605:3
601:d
594:D
582:=
579:U
555:D
533:)
528:r
523:(
520:V
500:)
495:r
490:(
467:)
462:r
457:(
454:V
434:)
429:r
424:(
399:Q
384:]
351:Q
321:q
317:C
291:q
287:C
283:=
274:q
271:Q
266:2
262:e
250:Q
207:O
203:N
186:B
139:B
133:=
128:L
20:)
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