A new specimen of ankylosaurine dinosaur Crichtonpelta benxiensis is described. The new specimen is based on a nearly completely preserved skull from the same quarry as the holotype of the mid-Cretaceous Sunjiawan For...A new specimen of ankylosaurine dinosaur Crichtonpelta benxiensis is described. The new specimen is based on a nearly completely preserved skull from the same quarry as the holotype of the mid-Cretaceous Sunjiawan Formation in Shuangmiao, Beipiao City, Liaoning Province, China. Cladistic analysis incorporating new information from the new specimen resolves Crichtonpelta benxiensis is more advanced than basal members of Ankylosauridae （Kunbarrasaurus, Liaoningosaurus, Chuanqiiong, Cedarpelta, Gobisaurus and Shamosaurus） and represents the first diverging branch of Ankylosaurinae. Comparisons to other mid-Cretaceous ankylosaurid-bearing dinosaur assemblages in northern China indicate a late Early Cretaceous to early Late Cretaceous age for the Shuangmiao dinosaur assemblage.展开更多
A novel solid-phase extraction(SPE)strategy based on polypyrrole(Ppy)nanofibers was developed for the determination of trace methotrexate and its polyglutamate metabolites(MTXs)in hospital effluents.Ppy was coated on ...A novel solid-phase extraction(SPE)strategy based on polypyrrole(Ppy)nanofibers was developed for the determination of trace methotrexate and its polyglutamate metabolites(MTXs)in hospital effluents.Ppy was coated on the surface of electrospun polystyrene nanofibers by in situ oxidative polymerization to form Ppy electrospun nanofibers.The mechanism of adsorption on MTXs was explored through static adsorption studies.The MTX contents,after extraction,were determined by liquid chromatography-tandem mass spectrometry analysis.Results show that the physical/chemical adsorption of targets occurs on the surface of Ppy nanofibers,which is most likely dominated by multiple adsorptions and heterogeneous adsorption sites.Ppy nanofibers exhibit satisfying extraction performance.The content of targets detected in medical wastewater samples ranges from 21 to 2908 ng/L.The novel strategy based on Ppy nanofiber SPE can extract trace MTXs effectively,guarantee analytical accuracy,and circumvent the storage and transportation of water samples during on-site sampling operations.展开更多
Crystallization is a widely used product refining process.Understanding the characteristics of the crystallization process in the petrochemical industry is helpful to selecting and designing new crystallization proces...Crystallization is a widely used product refining process.Understanding the characteristics of the crystallization process in the petrochemical industry is helpful to selecting and designing new crystallization processes.This review briefly introduces the characteristics of the crystallization process,summarizes the crystallization processes applied in petrochemical industry,and discusses some points for crystallization process design.Crystallization in the petrochemical process is mainly used in the purification of polymer monomers and is often a unit operation in the whole refining process.Designing a reasonable crystallization process requires consideration of process safety,feasibility,and economy from an overall perspective.展开更多
Cultural center is one of the important strategic functions of Beijing. It has become the top priority of financial investment in 2019. The budget of Beijing municipal government departments shows that the municipal b...Cultural center is one of the important strategic functions of Beijing. It has become the top priority of financial investment in 2019. The budget of Beijing municipal government departments shows that the municipal budget strongly supports cultural heritage protection, tourism culture, museums, industrial heritage transformation and physical bookstores. In 2019, RMB 400 million will be spent building subcenter museums and libraries.展开更多
基金provided by the National Natural Science Foundation of China(Grant No.41688103 and 41472020)
文摘A new specimen of ankylosaurine dinosaur Crichtonpelta benxiensis is described. The new specimen is based on a nearly completely preserved skull from the same quarry as the holotype of the mid-Cretaceous Sunjiawan Formation in Shuangmiao, Beipiao City, Liaoning Province, China. Cladistic analysis incorporating new information from the new specimen resolves Crichtonpelta benxiensis is more advanced than basal members of Ankylosauridae （Kunbarrasaurus, Liaoningosaurus, Chuanqiiong, Cedarpelta, Gobisaurus and Shamosaurus） and represents the first diverging branch of Ankylosaurinae. Comparisons to other mid-Cretaceous ankylosaurid-bearing dinosaur assemblages in northern China indicate a late Early Cretaceous to early Late Cretaceous age for the Shuangmiao dinosaur assemblage.
基金The National Natural Science Foundation of China(No.82173575)。
文摘A novel solid-phase extraction(SPE)strategy based on polypyrrole(Ppy)nanofibers was developed for the determination of trace methotrexate and its polyglutamate metabolites(MTXs)in hospital effluents.Ppy was coated on the surface of electrospun polystyrene nanofibers by in situ oxidative polymerization to form Ppy electrospun nanofibers.The mechanism of adsorption on MTXs was explored through static adsorption studies.The MTX contents,after extraction,were determined by liquid chromatography-tandem mass spectrometry analysis.Results show that the physical/chemical adsorption of targets occurs on the surface of Ppy nanofibers,which is most likely dominated by multiple adsorptions and heterogeneous adsorption sites.Ppy nanofibers exhibit satisfying extraction performance.The content of targets detected in medical wastewater samples ranges from 21 to 2908 ng/L.The novel strategy based on Ppy nanofiber SPE can extract trace MTXs effectively,guarantee analytical accuracy,and circumvent the storage and transportation of water samples during on-site sampling operations.
文摘Crystallization is a widely used product refining process.Understanding the characteristics of the crystallization process in the petrochemical industry is helpful to selecting and designing new crystallization processes.This review briefly introduces the characteristics of the crystallization process,summarizes the crystallization processes applied in petrochemical industry,and discusses some points for crystallization process design.Crystallization in the petrochemical process is mainly used in the purification of polymer monomers and is often a unit operation in the whole refining process.Designing a reasonable crystallization process requires consideration of process safety,feasibility,and economy from an overall perspective.
文摘Cultural center is one of the important strategic functions of Beijing. It has become the top priority of financial investment in 2019. The budget of Beijing municipal government departments shows that the municipal budget strongly supports cultural heritage protection, tourism culture, museums, industrial heritage transformation and physical bookstores. In 2019, RMB 400 million will be spent building subcenter museums and libraries.
