20:
368:," stated first author Suchitra Sebastian. Noted Fisher: "Our research group focuses on new materials with unconventional magnetic and electronic properties. Han Purple was first synthesized over 2,500 years ago, but we have only recently discovered how exotic its magnetic behavior is. It makes you wonder what other materials are out there that we haven't yet even begun to explore."
542:
The solid-state reaction to produce barium copper silicates starts at roughly 900 °C. Han purple is formed fastest. Han blue forms when an excess of silica is present and a longer reaction time is allowed. Early
Chinese manufacture generally produced a mixture of Han blue and Han purple
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Han purple fades in acid, so colorless particles found in pigments containing Han blue and Han purple may be particles which were originally purple, but which faded in acidic conditions in burial. In addition, Han blue has fungicidal properties, so preserves better. Han purple reacts with
336:"We have shown, for the first time, that the collective behavior in a bulk three-dimensional material can actually occur in just two dimensions. Low dimensionality is a key ingredient in many exotic theories that purport to account for various poorly understood phenomena, including
1677:
Cheng, Xiaolin; Xia, Yin; Ma, Yanru; Lei, Yong (2007). "Three fabricated pigments (Han purple, indigo and emerald green) in ancient
Chinese artifacts studied by Raman microscopy, energy-dispersive X-ray spectrometry and polarized light microscopy".
945:. The warriors were fired at the same temperature as that needed for the manufacture of Han purple (950–1,050 °C ), so the same kilns may have been used for both processes. No evidence indicates Han blue being used for the warriors (
937:—the expense of producing Han purple and other pigments in such large quantities would have emphasized luxury and status. Han purple seems to have mostly been used on the trousers (pants) of the warriors. The pigment was bound to the
327:
In 2006 scientists at
Stanford, Los Alamos National Laboratory and the Institute for Solid State Physics (University of Tokyo), showed that Han purple "loses a dimension" under suitable conditions when it enters a new state, as a
823:
was introduced, since they link pigment manufacture to the ideology of Taoism. Berke (2007) believes that political changes stopped the distribution of the pigments as the
Chinese Empire was split at the end of the Han period.
594:, and the control of the environment. Technology for achieving and maintaining high temperatures would have been known from metal and ceramic production e.g. the potential use of twin bellows as used in metal production.
439:). The rarity of witherite may favor baryte as the most likely source. Baryte has a slower decomposition rate and so favors Han blue production. Witherite conversely favors Han purple. In the use of baryte, lead salts (
408:. This is the area with large deposits of raw materials. No written records have been found about the production of Han purple or Han blue, so information about manufacture has been achieved through experimentation.
582:
The temperature needed to be high (around 900–1000 °C) and kept at that temperature for long periods. Han purple is thermally sensitive, so temperature control for producing Han purple needed to be fairly constant
1169:
Thieme, C. 2001. (translated by M. Will) Paint Layers and
Pigments on the Terracotta Army: A Comparison with Other Cultures of Antiquity. In: W. Yongqi, Z. Tinghao, M. Petzet, E. Emmerling and C. Blänsdorf (eds.)
774:
That earlier alkali metal glazing techniques were based on knowledge from Egypt, but that the copper silicate pigments (Egyptian blue and Han blue) developed from these glazes in two independent areas: Egypt and
1296:
Wiedemann, H. G. Bayer, G. and Reller, A. 1998. Egyptian blue and
Chinese blue. Production technologies and applications of two historically important blue pigments. In: S. Colinart and M. Menu (eds.)
1715:
Zuo, Jian; Zhao, Xichen; Wu, Ruo; Du, Guangfen; Xu, Cunyi; Wang, Changsui (2003). "Analysis of the pigments on painted pottery figurines from the Han
Dynasty's Yangling Tombs by Raman microscopy".
843:
The Han pigments consist of varying combinations of blue, purple and colorless components. The grinding together of Han purple and Han blue would have allowed a variety of blue-purple shades.
1272:
Wiedemann, H. G. and Berke, H. 2001. Chemical and
Physical Investigations of Egyptian and Chinese Blue and Purple. In: W. Yongqi, Z. Tinghao, M. Petzet, E. Emmerling and C. Blänsdorf (eds.)
1660:
Rogner, I. 2001. New
Methods to Characterise and to Consolidate the Polychrome Qi-lacquer of the Terracotta Army. In: W. Yongqi, Z. Tinghao, M. Petzet, E. Emmerling and C. Blänsdorf (eds.)
364:"Spin currents are capable of carrying far more information than a conventional charge current—which makes them the ideal vehicle for information transport in future applications such as
1533:
Liu, Z.; Mehta, A.; Tamura, N.; Pickard, D.; Rong, B.; Zhou, T.; Pianetta, P. (2007). "Influence of Taoism on the invention of the purple pigment used on the Qin terracotta warriors".
587:. Han blue is thermally less sensitive. Under the right conditions, the manufacture of Han purple would have taken around 10–24 hours, while Han blue would have taken twice as long.
909:
These are compact bodies (solid sticks/rods) with shades ranging from light blue to dark purple. The range of colors is due to varying proportions of Han blue, Han purple, and
1046:. The light blue color of this coordination polymer may explain the light blue color of some of the Terracotta Warriors' trousers – the color resulting from the presence of
767:. Independent innovation in China would still have been needed to replace calcium with barium (the Han pigments start to form at 100 – 200°C higher than the Egyptian blue).
292:
Han blue, like Han purple, has a layered structure with silicate forming the structural framework. However, Han blue is more stable because of structural features such as
794:
and Han purple and Han blue has been used to suggest a connection between glassmaking and the manufacture of pigments, and to argue for independent
Chinese invention.
1026:
formed in the decomposition of Han purple (see section on color) remains stable, but Han purple continues to deteriorate, and its purple color increases with time.
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material. They are thought to be pigment sticks which were traded then ground to be used as pigment bases in paints. They may have been of importance themselves, as
420:, a copper mineral, and a lead salt. It is unknown whether minerals were used in their natural form or were treated, though no evidence exists as yet of treatment.
385:. Han purple starts to decompose at temperatures more than 1050–1100 °C and forms a green-black glass at around 1200°C. It becomes more purplish when ground.
97:
was the only natural blue pigment used in early China. Early China seems not to have used a natural purple pigment and was the first to develop a synthetic one.
1013:
An Eastern Han-period tomb mural painting in the Xi'an area is one of the last examples of the use of synthetic barium copper silicate pigments (Han purple).
1274:
The Polychromy of Antique Sculptures and the Terracotta Army of the First Chinese Emperor: Studies on Materials, Painting Techniques and Conservation.
1172:
The Polychromy of Antique Sculptures and the Terracotta Army of the First Chinese Emperor: Studies on Materials, Painting Techniques and Conservation.
1755:
1662:
The Polychromy of Antique Sculptures and the Terracotta Army of the First Chinese Emperor: Studies on Materials, Painting Techniques and Conservation
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particles in various ratios, but pure colors were sometimes manufactured. Han blue could have been brought to a melt, but Han purple does not form a
1604:
1765:
319:
Han purple and blue are similar in many of their physical properties, which allow them to be mixed, but they differ in their chemical properties.
1399:
770:
The two hypotheses underlying the speculations about the exact chronology of the invention of these blue pigments can be summarized as follows:
146:. Perhaps the most accurate designation for the color would be to call it 'Han indigo', although it could also be regarded as a bright shade of
1341:
Berke, H.; Wiedemann, H. G. (2000). "The Chemistry and Fabrication of the Anthropogenic Pigments Chinese Blue and Purple in Ancient China".
787:
The case against links with Egyptian blue includes the absence of lead in Egyptian blue and the lack of examples of Egyptian blue in China.
743:
Han blue and Egyptian blue have the same basic structure and have very similar properties. The main difference is that Egyptian blue (CaCuSi
161:
O) which is formed when Han purple decomposes (the red and blue making purple). The decomposition of Han purple to form copper (I) oxide is
337:
778:
Alternatively, that examples of Han blue predate the official Silk Road and therefore that development was completely independent.
458:. The amount of lead is important. Too much lead (more than 5%) causes partial melting and glass formation above 1000 °C.
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Han blue is more chemically and thermally stable. It does not break down in dilute acids, and becomes more bluish when ground.
1428:
Conservation of Ancient Sites on the Silk Road: Proceedings of an International Conference on the Conservation of Grotto sites
1058:
Two other synthetic blue barium copper silicate compounds have been found in trace amounts, but are as yet unnamed. They are
815:
dynasties see a shift from lead-barium-silicate type glass to lead-soda-lime glass. The reason for decline is debatable. Liu
1426:
Wiedemann, H. G. and Bayer, G. 1997. Formation and Stability of Chinese Barium Copper-Silicate Pigments. In: N. Agnew (ed.)
1022:
Due to the instability of Han purple, it shows significant signs of weathering on archaeologically excavated artifacts. The
763:). The similarity led some to suggest that Han blue was based on Egyptian blue knowledge, which had traveled east along the
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Production seems to have been focused in northern China, around 200–300 km (120–190 mi) north of the city of
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The increase and decrease of barium glasses, and Han purple and Han blue, follow similar patterns. Both peaked in the
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447:) would have been needed to increase yield. Lead has been detected in association with Han purple and Han blue.
348:
Other research team members alluded to potential applications to quantum computing. In conventional computers,
329:
143:
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FitzHugh, E. W. and Zycherman, L. A. 1983. An Early Man-Made Blue Pigment from China: Barium Copper Silicate.
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Manufacturing depends on the raw materials, their ratios, fluxes, temperature, atmosphere, and reaction time.
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Temperature would have been controlled by testing of firing materials, the size, shape, and material of the
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Ancient pigment reveals secrets about unusual state of matter. National Science Foundation, July 11,2006
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Seligman, C. G.; Ritchie, P. D.; Beck, H. C. (1936). "Early Chinese Glass from Pre-Han to Tang Times".
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FitzHugh, E. W. and Zycherman, L. A. 1992. A Purple Barium Copper Silicate Pigment from Early China.
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Bronze vessels in the Han dynasty, e.g. a bowl and top of a steamer, were decorated with Han purple.
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Han purple and Han blue were first used in paints in the Qin dynasty. Han purple was used for the
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Some of the earliest examples of the use of the Han pigments are beads which date back to the
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Each four-ring silicate is linked to four others in the adjacent level, in a zig-zag pattern.
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were painted with a light blue pigment consisting of blue, purple, and colorless components.
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Artificial barium copper silicate pigments developed in ancient China during the Han dynasty
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Smaller painted pottery figurines have been found e.g. the Western Han dynasty Chu Tombs,
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The lead is used by pigment maker to lower the melting point of the barium in Han Purple.
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Berke, H. 2002. Chemistry in Ancient Times: The Development of Blue and Purple Pigments.
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Exotic properties and applications to superconductivity and quantum computing research
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Berke, Heinz (2007). "The Invention of Blue and Purple Pigments in Ancient Times".
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1605:"A Lost Purple Pigment, Where Quantum Physics and the Terracotta Warriors Collide"
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The purple color seen in samples of Han purple is created by the presence of red
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period. The pigments are either present as compact bodies or in glazed layers.
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3-D insulator called Han Purple loses a dimension to enter magnetic 'Flatland'
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229:). However, they differ in their formula, structure, and chemical properties.
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1300:. Actes de la Table Ronde Ravello, 20–22 mars 1997. Bari: Edipuglia, 195–203.
1384:"Purple Haze: Ancient Pigment Reveals Secrets About Unusual State Of Matter"
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and thermally less stable than Han blue. It fades and decomposes in dilute
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Effenbergerite mineral information. Mindat. Accessed September 23, 2008
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Han purple in its pure form is actually a dark blue, that is close to
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Both Han purple and Han blue are barium copper silicates (containing
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Prolonged firing causes Han purple to break down and form Han blue:
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and water vapor as by-products according to the following reaction:
285:. In 1993, it was discovered to occur naturally as the rare mineral
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may have developed Han purple from their knowledge of glassmaking.
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are very strongly contained within the stable silicate structure.
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La couleur dans la peinture et l'émaillage de l'Égypte ancienne
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126:. It is not, however, a purple in the way the term is used in
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Dye first made 2,500 years ago is focus of quantum spin study
1119: – Azure blue pigment made in pre-Columbian Mesoamerica
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Han blue and Han purple were used to decorate Han dynasty
269:
more unstable than Han blue (metal-metal bonds are rare).
100:
Han blue in its pure form is, as the name suggests, blue.
1430:. Los Angeles: The Getty Conservation Institute, 379–387.
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players, containing both Han blue and Han purple pigments
150:(classifying ultramarine as a color and not a pigment).
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attribute the decline to the decline of Taoism when
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1587:"Ancient Warriors and the Origin of Chinese Purple"
1125: – Blue colour associated with Persian pottery
965:Province and in the Han dynasty Yangling tombs of
790:The use of quartz, barium, and lead components in
454:in the decomposition of barium minerals and as a
340:, but until now there were no clear examples of '
1276:Monuments and Sites III. Paris: ICOMOS, 154–169.
832:Han blue seems to have been favored in earlier (
71:and used in ancient and imperial China from the
23:Detail of a mural from an Eastern Han tomb near
1664:. Monuments and Sites III. Paris:ICOMOS, 46–51.
416:The raw materials needed are a barium mineral,
1174:Monuments and Sites III. Paris: ICOMOS, 52–57.
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836:) periods, and Han purple in later periods (
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356:might in the future play a similar role in "
75:period (1045–771 BC) until the end of the
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1373:. Stanford University News, June 2, 2006
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277:Han blue has the chemical formula BaCuSi
233:Chemical formula and molecular structure
1454:Angewandte Chemie International Edition
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1113: – Pigment used in ancient Egypt
344:' in real materials," said Ian Fisher
7:
1768:(credit: Marcelo Jaime of MST-NHMFL)
547:melt, so it would have had to use a
811:, declining afterwards. Pre-Han to
663:Minimum temperature for production
482:The preparation of Han blue using
338:high-temperature superconductivity
14:
1535:Journal of Archaeological Science
193:breaks down to copper (I) oxide:
315:Chemical and physical properties
142:on the 'line of purples' on the
1766:Microscopic image of Han Purple
111:in the way the term is used in
1762:(Magnet Lab, FSU) May 21, 2006
969:and his Empress (156–141 BC).
494:as raw minerals also releases
118:, i.e., it is a color between
1:
1753:Raiders of the Lost Dimension
1717:Journal of Raman Spectroscopy
1681:Journal of Raman Spectroscopy
1006:from a Han dynasty tomb near
882:Ceramic vessels (Han dynasty)
423:The barium source was either
332:. The researchers noted that
80:
888:Wall paintings (Han dynasty)
846:The pigments were used for:
721:Color increase when ground?
189:Above 1050 °C, the CuO
981:dark grey pottery vessels.
885:Metal objects (Han dynasty)
352:transport information, but
1838:
1145:List of inorganic pigments
688:Decomposition temperature
1565:10.1016/j.jas.2007.01.005
1355:10.1163/26669323-01701006
1131: – Synthetic pigment
953:Painted pottery figurines
828:Uses in cultural contexts
478:The manufacturing process
257:Han purple has a layered
949:was used for the blue).
330:Bose-Einstein Condensate
144:CIE chromaticity diagram
1504:Studies in Conservation
1480:Studies in Conservation
933:in the tomb of Emperor
857:Octagonal sticks (from
1243:10.1002/chin.200719227
854:period (1201–771 BC) )
370:
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1135:Ancient Chinese glass
921:items of importance.
859:Warring States period
792:ancient Chinese glass
461:The role of lead is:
362:
342:dimensional reduction
334:
261:with isolated 4-ring
22:
1807:Copper(II) compounds
1107: – Blue pigment
1050:-excreting lichens.
739:Hypothesis on origin
691:1050 – 1100 °C
1729:2003JRSp...34..121Z
1694:2007JRSp...38.1274C
1632:1936Natur.138..721S
1607:. 18 December 2014.
1591:Stanford University
1547:2007JArSc..34.1878L
875:Painted figurines (
666:900 – 1000 °C
242:Han purple has the
1797:Inorganic pigments
1758:2014-12-25 at the
1402:2017-01-07 at the
1089:(light blue color)
699:Thermally stable?
37:
31:showing a pair of
1456:41/14, 2483–2487.
850:Beads (from late
783:Chinese invention
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730:
694:>1200 °C
677:Manufacture time
366:quantum computing
191:copper (II) oxide
132:nonspectral color
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1802:Barium compounds
1787:Shades of violet
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1593:. 30 March 2007.
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390:
387:
377:Han purple is
374:
371:
324:
321:
316:
313:
312:
311:
304:
301:
287:effenbergerite
282:
278:
274:
271:
251:
247:
239:
236:
234:
231:
210:
207:
206:
205:
202:
198:
187:
186:
182:
178:
174:
170:
166:
158:
91:
88:
48:Chinese purple
15:
13:
10:
9:
6:
4:
3:
2:
1834:
1823:
1822:Ancient China
1820:
1818:
1815:
1813:
1810:
1808:
1805:
1803:
1800:
1798:
1795:
1793:
1790:
1788:
1785:
1783:
1780:
1779:
1777:
1767:
1764:
1761:
1757:
1754:
1751:
1750:
1746:
1738:
1734:
1730:
1726:
1722:
1718:
1711:
1708:
1703:
1699:
1695:
1691:
1687:
1683:
1682:
1673:
1671:
1667:
1663:
1657:
1654:
1649:
1645:
1641:
1637:
1633:
1629:
1626:(3495): 721.
1625:
1621:
1614:
1611:
1606:
1600:
1597:
1592:
1588:
1582:
1579:
1574:
1570:
1566:
1562:
1557:
1552:
1548:
1544:
1540:
1536:
1529:
1527:
1525:
1523:
1521:
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1517:
1515:
1513:
1509:
1505:
1499:
1497:
1495:
1493:
1491:
1489:
1485:
1481:
1475:
1473:
1471:
1469:
1467:
1465:
1463:
1459:
1455:
1449:
1447:
1445:
1443:
1441:
1439:
1437:
1433:
1429:
1423:
1421:
1419:
1417:
1415:
1413:
1409:
1405:
1401:
1398:
1393:
1390:
1385:
1379:
1376:
1372:
1369:
1364:
1361:
1356:
1352:
1348:
1344:
1337:
1335:
1333:
1331:
1329:
1327:
1325:
1323:
1321:
1319:
1315:
1311:
1306:
1303:
1299:
1293:
1291:
1289:
1287:
1285:
1283:
1279:
1275:
1269:
1267:
1265:
1263:
1261:
1259:
1257:
1255:
1253:
1249:
1244:
1240:
1236:
1232:
1225:
1223:
1221:
1219:
1217:
1215:
1213:
1211:
1209:
1207:
1205:
1203:
1201:
1199:
1197:
1195:
1193:
1191:
1189:
1187:
1185:
1183:
1181:
1177:
1173:
1166:
1164:
1162:
1160:
1156:
1150:
1146:
1143:
1141:
1138:
1136:
1133:
1130:
1129:Prussian blue
1127:
1124:
1121:
1118:
1115:
1112:
1111:Egyptian blue
1109:
1106:
1103:
1101:
1100:Blue pigments
1098:
1097:
1093:
1076:
1061:
1060:
1059:
1053:
1051:
1049:
1033:
1027:
1025:
1017:
1012:
1009:
1005:
1001:
997:
996:
992:
990:
985:Metal objects
984:
982:
980:
972:
970:
968:
967:Emperor Liuqi
964:
960:
952:
950:
948:
944:
941:surface with
940:
936:
935:Qin Shi Huang
932:
924:
922:
920:
916:
912:
904:
902:
900:
892:
887:
884:
881:
878:
874:
871:
867:
863:
860:
856:
853:
849:
848:
847:
844:
841:
839:
835:
827:
825:
822:
818:
814:
810:
805:
802:
800:
797:
793:
788:
782:
777:
773:
772:
771:
768:
766:
754:
738:
733:
726:
723:
720:
719:
715:
712:
709:
708:
704:
701:
698:
697:
693:
690:
687:
686:
682:
679:
676:
675:
672:1000 °C
671:
668:
665:
662:
661:
653:(BaO·CuO·4SiO
642:
635:(BaO·CuO·2SiO
624:
622:
615:
614:
610:
607:
604:
603:
597:
595:
593:
588:
557:
556:
555:
552:
550:
546:
501:
500:
499:
497:
493:
489:
485:
477:
464:
463:
462:
459:
457:
453:
448:
446:
442:
434:
426:
421:
419:
412:Raw materials
411:
409:
407:
402:
396:
394:
388:
386:
384:
380:
372:
369:
367:
361:
359:
355:
354:electron spin
351:
345:
343:
339:
333:
331:
322:
320:
314:
309:
305:
302:
299:
295:
294:
293:
290:
288:
272:
270:
268:
264:
260:
255:
245:
237:
232:
230:
228:
224:
220:
216:
208:
196:
195:
194:
192:
164:
163:
162:
156:
151:
149:
145:
141:
137:
133:
129:
128:color science
125:
121:
117:
114:
110:
106:
101:
98:
96:
89:
87:
84: 220 AD
78:
74:
70:
67:developed in
66:
63:
60:
57:
53:
49:
46:(also called
45:
41:
34:
30:
26:
21:
1720:
1716:
1710:
1688:(10): 1274.
1685:
1679:
1661:
1656:
1623:
1619:
1613:
1599:
1590:
1581:
1541:(11): 1878.
1538:
1534:
1506:28/1, 15–23.
1503:
1482:28/1, 15–23.
1479:
1453:
1427:
1392:
1378:
1370:
1363:
1346:
1342:
1305:
1297:
1273:
1234:
1230:
1171:
1123:Persian blue
1074:(blue color)
1057:
1028:
1021:
1018:Preservation
988:
976:
956:
928:
919:bureaucratic
908:
899:Western Zhou
896:
852:Western Zhou
845:
842:
837:
831:
821:Confucianism
816:
806:
803:
789:
786:
769:
742:
669:
589:
581:
553:
541:
481:
469:+ PbO ⇌ PbSO
460:
449:
422:
415:
403:
400:
392:
376:
363:
347:
335:
326:
318:
291:
276:
256:
241:
212:
197:4 CuO → 2 Cu
188:
152:
102:
99:
93:
73:Western Zhou
52:Chinese blue
51:
47:
43:
39:
38:
1397:Purple Haze
1105:Cobalt blue
1032:oxalic acid
877:Han dynasty
870:Qin dynasty
809:Han dynasty
608:Han purple
545:homogeneous
397:Manufacture
360:" devices:
306:The copper
296:It is more
148:ultramarine
77:Han dynasty
1776:Categories
1723:(2): 121.
1349:: 94–120.
1231:ChemInform
1151:References
939:terracotta
915:ceremonial
840:400 BC).
799:alchemists
598:Comparison
522:→ 2 BaCuSi
445:lead oxide
379:chemically
373:Han purple
358:spintronic
238:Han purple
113:colloquial
107:. It is a
40:Han purple
1817:Silicates
1551:CiteSeerX
1117:Maya blue
911:colorless
765:Silk Road
611:Han blue
585:(± 50 °C)
574:+ 2 BaSiO
551:process.
549:sintering
492:witherite
484:malachite
425:witherite
263:silicates
259:structure
209:Chemistry
181:+ 2 BaSiO
130:, i.e. a
1792:Pigments
1756:Archived
1573:17797649
1400:Archived
1094:See also
1004:pediment
566:→ BaCuSi
558:3 BaCuSi
518:+ 2 BaCO
452:catalyst
389:Han blue
273:Han blue
267:compound
173:→ BaCuSi
165:3 BaCuSi
134:between
65:pigments
62:silicate
44:Han blue
1725:Bibcode
1690:Bibcode
1648:4097744
1628:Bibcode
1543:Bibcode
1048:oxalate
1008:Luoyang
963:Jiangsu
947:azurite
943:lacquer
753:calcium
734:History
578:+ 2 CuO
514:+ 8 SiO
223:silicon
185:+ 2 CuO
116:English
95:Azurite
25:Luoyang
1812:Oxides
1646:
1620:Nature
1571:
1553:
1237:(19).
1000:lintel
959:Xuzhou
817:et al.
796:Taoist
775:China.
751:) has
643:BaCuSi
625:BaCuSi
530:+ 3 CO
488:silica
433:baryte
418:quartz
300:-rich.
298:silica
246:BaCuSi
227:oxygen
225:, and
219:copper
215:barium
140:violet
109:purple
105:indigo
59:copper
56:barium
1644:S2CID
1569:S2CID
1054:Notes
893:Beads
838:circa
670:circa
510:)(OH)
473:+ BaO
435:(BaSO
431:) or
427:(BaCO
406:Xi'an
201:O + O
90:Color
69:China
33:Liubo
29:Henan
1081:CuSi
1062:BaCu
1002:and
864:The
834:Zhou
813:Tang
727:Yes
724:Yes
716:Yes
705:Yes
592:kiln
490:and
465:BaSO
456:flux
383:acid
308:ions
138:and
124:blue
122:and
50:and
42:and
1733:doi
1698:doi
1636:doi
1624:138
1561:doi
1351:doi
1239:doi
917:or
713:No
702:No
534:+ H
506:(CO
443:or
157:(Cu
136:red
120:red
86:).
1778::
1731:.
1721:34
1719:.
1696:.
1686:38
1684:.
1669:^
1642:.
1634:.
1622:.
1589:.
1567:.
1559:.
1549:.
1539:34
1537:.
1511:^
1487:^
1461:^
1435:^
1411:^
1347:17
1345:.
1317:^
1281:^
1251:^
1235:38
1233:.
1179:^
1158:^
1077:Ba
1066:Si
998:A
979:Hu
961:,
761:10
749:10
649:10
572:10
528:10
502:Cu
486:,
289:.
283:10
254:.
221:,
217:,
179:10
81:c.
27:,
1739:.
1735::
1727::
1704:.
1700::
1692::
1650:.
1638::
1630::
1575:.
1563::
1545::
1386:.
1357:.
1353::
1312:"
1245:.
1241::
1087:7
1085:O
1083:2
1079:2
1072:7
1070:O
1068:2
1064:2
1044:2
1042:)
1040:4
1038:O
1036:2
879:)
872:)
868:(
861:)
759:O
757:4
747:O
745:4
657:)
655:2
647:O
645:4
639:)
637:2
631:6
629:O
627:2
576:3
570:O
568:4
564:6
562:O
560:2
538:O
536:2
532:2
526:O
524:4
520:3
516:2
512:2
508:3
504:2
471:4
467:4
437:4
429:3
281:O
279:4
252:6
250:O
248:2
203:2
199:2
183:3
177:O
175:4
171:6
169:O
167:2
159:2
79:(
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