The aim of ＂green chemistry＂ and ＂atom economy＂ is to utilize carbon dioxide and replace harmful reactants such as CO and phosgene for the production of cyclic carbonates. In this paper, metal-free catalysts inclu...The aim of ＂green chemistry＂ and ＂atom economy＂ is to utilize carbon dioxide and replace harmful reactants such as CO and phosgene for the production of cyclic carbonates. In this paper, metal-free catalysts including organic bases, ionic liquids, supported catalysts, organic copolymers and carbon materials for the synthesis of cyclic carbonates by the cycloaddition of carbon dioxide to epoxides are reviewed. Recent advances in the design of the catalysts and the understanding of the reaction mechanism are summarized and discussed. The synergistic effects of organic bases and hydrogen bond donors, organic bases and nucleophilic anions, hydrogen bond donors and nucleophilic anions and active components and supports are highlighted. The challenge is to develop metal-free catalysts suitable for carbon dioxide capture and fixation. The ultimate goal is to synthesize cyclic carbonates in a flow reactor directly using carbon dioxide from industrial flue gas at ambient temperature and atmospheric pressure. By using synergetic effects, a multi-functional approach can meet the design strategy of metal-free catalysts for carbon dioxide adsorption and activation as well as epoxide ring opening.展开更多
Objective:To screen,identify,and compare the serum biomarkers between anovulatory dysfunctional uterine bleeding(ADUB)and ovulatory dysfunctional uterine bleeding(ODUB)in Lizu females.Methods:The subjects included 128...Objective:To screen,identify,and compare the serum biomarkers between anovulatory dysfunctional uterine bleeding(ADUB)and ovulatory dysfunctional uterine bleeding(ODUB)in Lizu females.Methods:The subjects included 128 ADLB patients,63 ODUB patients,and 93controls.The serum and supernate of the subjects'mense were collected and stored at-80°C until use.Differential proteins in the sera of three groups were screened using surface-enhaneed laser desorption ionization time-of-flight mass spectrometry.The screened proteins were then identified by tricine-SDS-PAGE gel and spectrometry.Protein expression levels in the menses of ADUB,ODUB,and control subjects were determined using ELISA,RT-PCR,and Western blotting.SPSS 14.1 was used for statistical analysis and chart drawing(a=0.05),Results:Three differentia)protein peaks with peak values of 11.80,13.59,and 14.68 km/z were,screened and identified as serum amyploid protein A(SAA),vascular endothelial growth factor,and vitamin K epoxide reductase,respectively.The SAA was highly expressed in the menses of ADUB and ODUB patients but poorly expressed in the controls.The vascular endothelial growth factor was highly expressed in the menses of ODUB and controls but poorly expressed in ADUB patients.Meanwhile,the vitamin K epoxide reductase was highly expressed in the menses of ADUB and control subjects but poorly expressed in ODUB patients.Conclusions:The SAA is the common serum biomarker of ADUB and ODUB.ADUB may be related to angiogenesis impairment,whereas ODUB may be associated with blood coagulation disruption.展开更多
基金supported by the National Science and Technology Support Project of China(2013BAC11B03)the National Natural Science Foundation of China(21401054,21476065,21273067)the Graduate Student Scientific Research Innovation Fund Project of Hunan Province(CX2015B082)~~
文摘The aim of ＂green chemistry＂ and ＂atom economy＂ is to utilize carbon dioxide and replace harmful reactants such as CO and phosgene for the production of cyclic carbonates. In this paper, metal-free catalysts including organic bases, ionic liquids, supported catalysts, organic copolymers and carbon materials for the synthesis of cyclic carbonates by the cycloaddition of carbon dioxide to epoxides are reviewed. Recent advances in the design of the catalysts and the understanding of the reaction mechanism are summarized and discussed. The synergistic effects of organic bases and hydrogen bond donors, organic bases and nucleophilic anions, hydrogen bond donors and nucleophilic anions and active components and supports are highlighted. The challenge is to develop metal-free catalysts suitable for carbon dioxide capture and fixation. The ultimate goal is to synthesize cyclic carbonates in a flow reactor directly using carbon dioxide from industrial flue gas at ambient temperature and atmospheric pressure. By using synergetic effects, a multi-functional approach can meet the design strategy of metal-free catalysts for carbon dioxide adsorption and activation as well as epoxide ring opening.
基金supported by the Natural Seience Foundation of Hainan Province(30633,812148)
文摘Objective:To screen,identify,and compare the serum biomarkers between anovulatory dysfunctional uterine bleeding(ADUB)and ovulatory dysfunctional uterine bleeding(ODUB)in Lizu females.Methods:The subjects included 128 ADLB patients,63 ODUB patients,and 93controls.The serum and supernate of the subjects'mense were collected and stored at-80°C until use.Differential proteins in the sera of three groups were screened using surface-enhaneed laser desorption ionization time-of-flight mass spectrometry.The screened proteins were then identified by tricine-SDS-PAGE gel and spectrometry.Protein expression levels in the menses of ADUB,ODUB,and control subjects were determined using ELISA,RT-PCR,and Western blotting.SPSS 14.1 was used for statistical analysis and chart drawing(a=0.05),Results:Three differentia)protein peaks with peak values of 11.80,13.59,and 14.68 km/z were,screened and identified as serum amyploid protein A(SAA),vascular endothelial growth factor,and vitamin K epoxide reductase,respectively.The SAA was highly expressed in the menses of ADUB and ODUB patients but poorly expressed in the controls.The vascular endothelial growth factor was highly expressed in the menses of ODUB and controls but poorly expressed in ADUB patients.Meanwhile,the vitamin K epoxide reductase was highly expressed in the menses of ADUB and control subjects but poorly expressed in ODUB patients.Conclusions:The SAA is the common serum biomarker of ADUB and ODUB.ADUB may be related to angiogenesis impairment,whereas ODUB may be associated with blood coagulation disruption.
