The europium-doped LaF3 nanoparticles were prepared by refluxing method in glycerol/water mixture and characterized with X-ray diffraction(XRD), field emission scanning electron microscopy(FE-SEM), UV-vis diffuse ...The europium-doped LaF3 nanoparticles were prepared by refluxing method in glycerol/water mixture and characterized with X-ray diffraction(XRD), field emission scanning electron microscopy(FE-SEM), UV-vis diffuse reflectance spectrum, and photoluminescence spectra.The results of XRD indicated that the obtained LaF3:Eu^3+ nanoparticles were well crystallized with a hexagonal structure.The FE-SEM image illustrated that the LaF3:Eu^3+ nanoparticles were spherical with an average size around 30 nm.Under irradiation of UV light, the emission spectrum of LaF3:Eu^3+ nanoparticles exhibited the characteristic line emissions arising from the 5D0→7FJ(J=1, 2, 3, 4) transitions of the Eu3+ ions, with the dominating emission centered at 590 nm.In addition, the emissions from the 5D1 level could be clearly observed due to the low phonon energies(-350 cm^-1) of LaF3 matrix.The optimum doping concentration for LaF3:Eu3+ nanoparticles was determined to be 20mol.%.展开更多
The complex fluoride, KNiF3, with perovskite structure was synthesized by refluxing KF and Ni(NO3)2·6H20 in ethanediol. The samples were characterized by X-ray diffraction(XRD), transmission electron microsc...The complex fluoride, KNiF3, with perovskite structure was synthesized by refluxing KF and Ni(NO3)2·6H20 in ethanediol. The samples were characterized by X-ray diffraction(XRD), transmission electron microscopy(TEM), X-ray photoelectron spectroscopy(XPS), and ultraviolet-visible diffuse reflectance speetroseopy(UV-Vis DRS). The results indicate that the mean diameter of KNiF3 particles is about 30-60 nm and the oxygen content in the samples is ≤5%. The prepared KNiF3 shows obvious absorption peaks at 400-830 nm.展开更多
With Pueraria edulis from different habitats in Yunnan Province,Guangdong Province and Guangxi Zhuang autonomous region as materials,the medicinal materials of P.edulis were extracted by ethanol condensation reflux ex...With Pueraria edulis from different habitats in Yunnan Province,Guangdong Province and Guangxi Zhuang autonomous region as materials,the medicinal materials of P.edulis were extracted by ethanol condensation reflux extraction and ultrasound-assisted extraction,and the effects of different extraction methods the contents of total flavonoids in P.edulis from different areas were compared.The results showed that the best extraction time for P.edulis in Yunnan Province was 20 min,and that for Guangdong and Guangxi Zhuang Autonomous Region was 30 min.The yield of total flavonoids from P.edulis extracted by the condensation reflux extraction method was relatively better.The content of total flavonoids in P.edulis in Yunnan was the highest with an average content of 0.2557%,while the average content of total flavonoids in P.edulis in Guangdong was the lowest with an average content of 0.2108%.展开更多
Nano structured LiFexMn1-xPO4 (x=0, 0.2, 0.4) materials were successfully prepared by one-step reflux method in a water/PEG400 mixed solvent, and were coated by carbon using glucose as the precursor. The materials w...Nano structured LiFexMn1-xPO4 (x=0, 0.2, 0.4) materials were successfully prepared by one-step reflux method in a water/PEG400 mixed solvent, and were coated by carbon using glucose as the precursor. The materials were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). The electrochemical properties of the materials were investigated by galvanostatic cycling, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). It was found that the materials consisted of nanorods with a diameter of 50 nm and a length of 500 nm. Galvanostatic cycling showed that the capacity of LiMnPO4 could be largely increased by Fe2+ substitution. At a current rate of C/20, the capacity of the three samples (x=0, 0.2, 0.4) were 47, 107 and 150 mA-h.g-1, respectively. CV result showed that the Fe2+ substitution could decrease the polarization during charging/discharging, ac- celerating the electrochemical process. EIS result showed that the Fe2+ substitution could decrease the charge transfer resistance between the electrode and electrolyte, as well as increase the Li-ion diffusion coefficient in the bulk material, resulting in an improved electrochemical performance.展开更多
We tried to develop an efficient strategy to isolate geniposide from Gardenia fruit and use it to treat chronic pain. Eight extraction solvents and three extraction methods were respectively compared with each other f...We tried to develop an efficient strategy to isolate geniposide from Gardenia fruit and use it to treat chronic pain. Eight extraction solvents and three extraction methods were respectively compared with each other for the efficiency of geniposide extraction from Gardenia fruit. Extraction with 80% ethanol under reflux was found to give the highest yield of geniposide. Orthogonal experiment was conducted to optimize the reflux conditions and the optimal conditions are a mass(of Gardeniajasminoides Ellis powder) to volume(of solvent, 80% ethanol) ratio of 1:7 and reflux twice for 60 rain each. The geniposide obtained by the reflux method was tested on the rats with chronic constriction injury(CCI) for pain relief. The results show that geniposide can enhance pain threshold and relieve pain via repressing tumor necrosis factor-a(TNF-a) expression in either ipsilateral or contralateral dorsal root gan- glion(DRG) cells. These results suggest that geniposide treatement may be an effective clinical method to relieve pain based on the mechanism of molecular biology at DRG due to nerve injury.展开更多
基金supported by the Natural Science Foundation of Henan Province (082300440130, 2008A180039, 2007150049)Startup Fund for Doctoral Program of Zhoukou Normal University
文摘The europium-doped LaF3 nanoparticles were prepared by refluxing method in glycerol/water mixture and characterized with X-ray diffraction(XRD), field emission scanning electron microscopy(FE-SEM), UV-vis diffuse reflectance spectrum, and photoluminescence spectra.The results of XRD indicated that the obtained LaF3:Eu^3+ nanoparticles were well crystallized with a hexagonal structure.The FE-SEM image illustrated that the LaF3:Eu^3+ nanoparticles were spherical with an average size around 30 nm.Under irradiation of UV light, the emission spectrum of LaF3:Eu^3+ nanoparticles exhibited the characteristic line emissions arising from the 5D0→7FJ(J=1, 2, 3, 4) transitions of the Eu3+ ions, with the dominating emission centered at 590 nm.In addition, the emissions from the 5D1 level could be clearly observed due to the low phonon energies(-350 cm^-1) of LaF3 matrix.The optimum doping concentration for LaF3:Eu3+ nanoparticles was determined to be 20mol.%.
基金Supported by the National Natural Science Foundation of China(No.20671069)
文摘The complex fluoride, KNiF3, with perovskite structure was synthesized by refluxing KF and Ni(NO3)2·6H20 in ethanediol. The samples were characterized by X-ray diffraction(XRD), transmission electron microscopy(TEM), X-ray photoelectron spectroscopy(XPS), and ultraviolet-visible diffuse reflectance speetroseopy(UV-Vis DRS). The results indicate that the mean diameter of KNiF3 particles is about 30-60 nm and the oxygen content in the samples is ≤5%. The prepared KNiF3 shows obvious absorption peaks at 400-830 nm.
基金Supported by Hunan Provincial University Innovation Platform Open Fund Project(19K049)。
文摘With Pueraria edulis from different habitats in Yunnan Province,Guangdong Province and Guangxi Zhuang autonomous region as materials,the medicinal materials of P.edulis were extracted by ethanol condensation reflux extraction and ultrasound-assisted extraction,and the effects of different extraction methods the contents of total flavonoids in P.edulis from different areas were compared.The results showed that the best extraction time for P.edulis in Yunnan Province was 20 min,and that for Guangdong and Guangxi Zhuang Autonomous Region was 30 min.The yield of total flavonoids from P.edulis extracted by the condensation reflux extraction method was relatively better.The content of total flavonoids in P.edulis in Yunnan was the highest with an average content of 0.2557%,while the average content of total flavonoids in P.edulis in Guangdong was the lowest with an average content of 0.2108%.
基金supported by Zijin Program of Zhejiang University, Chinathe Fundamental Research Funds for the Central Universities (No. 2010QNA4003)+3 种基金the Ph.D.Programs Foundation of Ministry of Education of China(No. 20100101120024)the Foundation of Education Office of Zhejiang Province, China (No. Y201016484)the Qianjiang Talents Project of Science Technology Department of Zhejiang Province, China (No. 2011R10021)the National Natural Science Foundation of China (No.51101139)
文摘Nano structured LiFexMn1-xPO4 (x=0, 0.2, 0.4) materials were successfully prepared by one-step reflux method in a water/PEG400 mixed solvent, and were coated by carbon using glucose as the precursor. The materials were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). The electrochemical properties of the materials were investigated by galvanostatic cycling, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). It was found that the materials consisted of nanorods with a diameter of 50 nm and a length of 500 nm. Galvanostatic cycling showed that the capacity of LiMnPO4 could be largely increased by Fe2+ substitution. At a current rate of C/20, the capacity of the three samples (x=0, 0.2, 0.4) were 47, 107 and 150 mA-h.g-1, respectively. CV result showed that the Fe2+ substitution could decrease the polarization during charging/discharging, ac- celerating the electrochemical process. EIS result showed that the Fe2+ substitution could decrease the charge transfer resistance between the electrode and electrolyte, as well as increase the Li-ion diffusion coefficient in the bulk material, resulting in an improved electrochemical performance.
基金Supported by the Natural Science Foundation of Jilin Province, China(No.20125059).
文摘We tried to develop an efficient strategy to isolate geniposide from Gardenia fruit and use it to treat chronic pain. Eight extraction solvents and three extraction methods were respectively compared with each other for the efficiency of geniposide extraction from Gardenia fruit. Extraction with 80% ethanol under reflux was found to give the highest yield of geniposide. Orthogonal experiment was conducted to optimize the reflux conditions and the optimal conditions are a mass(of Gardeniajasminoides Ellis powder) to volume(of solvent, 80% ethanol) ratio of 1:7 and reflux twice for 60 rain each. The geniposide obtained by the reflux method was tested on the rats with chronic constriction injury(CCI) for pain relief. The results show that geniposide can enhance pain threshold and relieve pain via repressing tumor necrosis factor-a(TNF-a) expression in either ipsilateral or contralateral dorsal root gan- glion(DRG) cells. These results suggest that geniposide treatement may be an effective clinical method to relieve pain based on the mechanism of molecular biology at DRG due to nerve injury.