Nature and evolution of the lithospheric mantle revealed by water contents and He-Ar isotopes of peridotite xenoliths from Changbaishan and Longgang basalts in Northeast China.

The nature and evolution of the lithospheric mantle underlying Northeast (NE) China were investigated by assessing the mineral chemistry, water contents, and noble gas (He-Ar) isotopes of peridotite xenoliths captured by Cenozoic basalts from the Changbaishan and Longgang regions. The xenoliths, which have 863-1141 °C equilibration temperatures, primarily comprise spinel lherzolites and rare spinel harzburgites. The Mg (Fo) values of olivine in the peridotite xenoliths vary from 86.

Synthesis of high-silica EU-1 zeolite in the presence of hexamethonium ions: a seeded approach for inhibiting ZSM-48.

A seeded approach was developed to synthesize high-silica EU-1 zeolite via inhibiting the co-crystallization of ZSM-48 in the presence of hexamethonium (HM) ions. A systematic study was carried out to determine factors such as seed content and SiO(2)/Al(2)O(3) ratio, which influenced the crystallization of high-silica EU-1 and transformation of EU-1 into ZSM-48. Using EU-1 seeds, not only well-crystallized pure EU-1 zeolites with SiO(2)/Al(2)O(3) ratios more than 500 were synthesized, but also the co-crystalline of ZSM-48/EU-1 or pure ZSM-48 was obtained in control from silica-rich mixture gels.