Owing to their high performance and earth abundance,copper sulfides(Cu_(2-x)S)have attracted wide attention as a promising medium-temperature thermoelectric material.Nanostructure and grain-boundary engineering are ex...Owing to their high performance and earth abundance,copper sulfides(Cu_(2-x)S)have attracted wide attention as a promising medium-temperature thermoelectric material.Nanostructure and grain-boundary engineering are explored to tune the electrical transport and phonon scattering of Cu_(2-x)S based on the liquid-like copper ion.Here multiscale architecture-engineered Cu_(2-x)S are fabricated by a room-temperature wet chemical synthesis combining mechanical mixing and spark plasma sintering.The observed electrical conductivity in the multiscale architecture-engineered Cu_(2-x)S is four times as much as that of the Cu_(2-x)S sample at 800 K,which is attributed to the potential energy filtering effect at the new grain boundaries.Moreover,the multiscale architecture in the sintered Cu_(2-x)S increases phonon scattering and results in a reduced lattice thermal conductivity of 0.2 W·m^(-1)·K^(-1) and figure of merit(zT)of 1.0 at 800 K.Such a zT value is one of the record values in copper sulfide produced by chemical synthesis.These results suggest that the introduction of nanostructure and formation of new interface are effective strategies for the enhancement of thermoelectric material properties.展开更多
All-trans-retinoic acid(atRA)plays an essential role in organ formation and differentiation,tissue cell proliferation,and apoptosis,and is closely related to the occurrence and development of various diseases.Liquid c...All-trans-retinoic acid(atRA)plays an essential role in organ formation and differentiation,tissue cell proliferation,and apoptosis,and is closely related to the occurrence and development of various diseases.Liquid chromatography-tandem mass spectrometry(LC-MS/MS)has become a powerful tool for metabolic biological analysis because of the high sensitivity,specificity and throughput.We have developed a new method for the quantification of atRA by chemical derivatization with 2-nitrophe-nylhydrazine(2-NPH)for the first time,which reduced the interference of detection by changing the ion mass of the molecule.atRA from its endogenous geometric isomers,such as,9-cis-RA and 13-cis-RA,has been baseline resolved within 15 minute under the optimized chromatographic conditions.The method was applied to measure atRA in mouse serum and tissues including liver,kidney,brain,pancreas,and subcutaneous tissue.The method is easy to operate,highly sensitive and well selective,and can be used for accurate and rapid determination of at RA in biological samples.展开更多
基金financially supported by the National Natural Science Foundation of China(Nos.51702091 and 51702046)the College Outstanding Young Scientific and Technological Innovation Team of Hubei province(No.T201922)+2 种基金the Special Funding of Preventing the Spread of COVID-19,Hubei University of Education(No.20XGZX20)Fok Ying-Tong Education Foundation of China(No.171041)the Program for Professor of Special Appointment(Eastern Scholar)at Shanghai Institutions of Higher Learning,State Key Laboratory for Modification of Chemical Fibers and Polymer Materials,Donghua University。
文摘Owing to their high performance and earth abundance,copper sulfides(Cu_(2-x)S)have attracted wide attention as a promising medium-temperature thermoelectric material.Nanostructure and grain-boundary engineering are explored to tune the electrical transport and phonon scattering of Cu_(2-x)S based on the liquid-like copper ion.Here multiscale architecture-engineered Cu_(2-x)S are fabricated by a room-temperature wet chemical synthesis combining mechanical mixing and spark plasma sintering.The observed electrical conductivity in the multiscale architecture-engineered Cu_(2-x)S is four times as much as that of the Cu_(2-x)S sample at 800 K,which is attributed to the potential energy filtering effect at the new grain boundaries.Moreover,the multiscale architecture in the sintered Cu_(2-x)S increases phonon scattering and results in a reduced lattice thermal conductivity of 0.2 W·m^(-1)·K^(-1) and figure of merit(zT)of 1.0 at 800 K.Such a zT value is one of the record values in copper sulfide produced by chemical synthesis.These results suggest that the introduction of nanostructure and formation of new interface are effective strategies for the enhancement of thermoelectric material properties.
基金Supported by the College Outstanding Young Scientific and Technological Innovation Team of Hubei Province(T201718)。
文摘All-trans-retinoic acid(atRA)plays an essential role in organ formation and differentiation,tissue cell proliferation,and apoptosis,and is closely related to the occurrence and development of various diseases.Liquid chromatography-tandem mass spectrometry(LC-MS/MS)has become a powerful tool for metabolic biological analysis because of the high sensitivity,specificity and throughput.We have developed a new method for the quantification of atRA by chemical derivatization with 2-nitrophe-nylhydrazine(2-NPH)for the first time,which reduced the interference of detection by changing the ion mass of the molecule.atRA from its endogenous geometric isomers,such as,9-cis-RA and 13-cis-RA,has been baseline resolved within 15 minute under the optimized chromatographic conditions.The method was applied to measure atRA in mouse serum and tissues including liver,kidney,brain,pancreas,and subcutaneous tissue.The method is easy to operate,highly sensitive and well selective,and can be used for accurate and rapid determination of at RA in biological samples.
