Whole-rock Sm-Nd isotopes were investigated for Cambrian-Ordovician strata from the Jinggangshan area between the Yangtze Block and Cathysia Block in South China. These strata were deposited as a greatly thick unit of...Whole-rock Sm-Nd isotopes were investigated for Cambrian-Ordovician strata from the Jinggangshan area between the Yangtze Block and Cathysia Block in South China. These strata were deposited as a greatly thick unit of muddy-sandy laminas with intercalated carbonate and organic carbon-bearing layers. They have low εNd(t) values of –13.9 to –7.9 and old Nd model ages of 1842 to 2375 Ma. In tDM-tStr diagram, they are far away from the concordant line but fall within the evolution zone of the Proterozoic crust of South China. This indicates that the Cambrian-Ordovician strata are mainly composed of mat- ters eroded from ancient Paleoproterozoic crust that may mainly consist of continental-derived detrital sediments with high maturity in the Cathysia Block. However, the Ordovician Jueshangou Formation and Dui’ershi Formation have εNd(t) values of –10.5 and –7.9 at the higher end of the above range and Nd model ages of 1842 to 2059 Ma at the lower end of the above range. This suggests involvement of more detritus that were eroded from the relatively juvenile crust from Late Paleoproterozoic to the Early Neoproterozoic. All the Nd model ages for the Cambrian-Ordovician sedimentary rocks in the Cathysia Block and the southeastern margin of the Yangtze Block are older than 1800 Ma, suggesting that no material from the Early Paleozoic depleted mantle-derived magmas was involved in these regions.展开更多
The oxidation of 2,3,6-trimethylphenol(TMP)can produce both 2,3,5-trimethyl-1,4-benzoquinone(TMQ)and 2,3,5-trimethyl-1,4-hydroquinone(TMHQ)as important intermediates of vitamin E.With a soluble and porous polymer of i...The oxidation of 2,3,6-trimethylphenol(TMP)can produce both 2,3,5-trimethyl-1,4-benzoquinone(TMQ)and 2,3,5-trimethyl-1,4-hydroquinone(TMHQ)as important intermediates of vitamin E.With a soluble and porous polymer of intrinsic microporosity(PIM-1),we developed a highly active and reusable CuO@PIM-1 catalyst for the aerobic oxidation of TMP to TMQ and TMHQ.The CuO@PIM-1 catalyst is high active and selective for the aerobic oxidation of TMP,and TMQ and TMHQ can be obtained in yields of 81%and 19%,respectively.The CuO@PIM-1 catalyst has both advantages of homogeneous and heterogeneous and the CuO@PIM-1 catalyst showed a higher activity than homogeneous(CuCl_(2))and heterogeneous(supported CuO)catalysts.Moreover,CuO@PIM-1 catalyst can be recovered easily and reused at least 5 times without deactivation.展开更多
基金Supported by National Natural Science Foundation of China (Grant Nos. 40634022 and 40572118)the Project of Ministry of Education of China (Grant No. 20060284008)
文摘Whole-rock Sm-Nd isotopes were investigated for Cambrian-Ordovician strata from the Jinggangshan area between the Yangtze Block and Cathysia Block in South China. These strata were deposited as a greatly thick unit of muddy-sandy laminas with intercalated carbonate and organic carbon-bearing layers. They have low εNd(t) values of –13.9 to –7.9 and old Nd model ages of 1842 to 2375 Ma. In tDM-tStr diagram, they are far away from the concordant line but fall within the evolution zone of the Proterozoic crust of South China. This indicates that the Cambrian-Ordovician strata are mainly composed of mat- ters eroded from ancient Paleoproterozoic crust that may mainly consist of continental-derived detrital sediments with high maturity in the Cathysia Block. However, the Ordovician Jueshangou Formation and Dui’ershi Formation have εNd(t) values of –10.5 and –7.9 at the higher end of the above range and Nd model ages of 1842 to 2059 Ma at the lower end of the above range. This suggests involvement of more detritus that were eroded from the relatively juvenile crust from Late Paleoproterozoic to the Early Neoproterozoic. All the Nd model ages for the Cambrian-Ordovician sedimentary rocks in the Cathysia Block and the southeastern margin of the Yangtze Block are older than 1800 Ma, suggesting that no material from the Early Paleozoic depleted mantle-derived magmas was involved in these regions.
基金This work was supported by the National Natural Science Foundation of China(No.21676140).
文摘The oxidation of 2,3,6-trimethylphenol(TMP)can produce both 2,3,5-trimethyl-1,4-benzoquinone(TMQ)and 2,3,5-trimethyl-1,4-hydroquinone(TMHQ)as important intermediates of vitamin E.With a soluble and porous polymer of intrinsic microporosity(PIM-1),we developed a highly active and reusable CuO@PIM-1 catalyst for the aerobic oxidation of TMP to TMQ and TMHQ.The CuO@PIM-1 catalyst is high active and selective for the aerobic oxidation of TMP,and TMQ and TMHQ can be obtained in yields of 81%and 19%,respectively.The CuO@PIM-1 catalyst has both advantages of homogeneous and heterogeneous and the CuO@PIM-1 catalyst showed a higher activity than homogeneous(CuCl_(2))and heterogeneous(supported CuO)catalysts.Moreover,CuO@PIM-1 catalyst can be recovered easily and reused at least 5 times without deactivation.
