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
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
Bismuth-doped tin dioxide (BTO) nanometer powders were prepared by the wet chemical method using tin tetrachloride (SnCl4), bismuth nitrate [Bi(NO3) 3 ] and ammonia as raw materials. Non-bridge hydroxides and ca...Bismuth-doped tin dioxide (BTO) nanometer powders were prepared by the wet chemical method using tin tetrachloride (SnCl4), bismuth nitrate [Bi(NO3) 3 ] and ammonia as raw materials. Non-bridge hydroxides and capillary force between particles were found to be key factors causing hard aggregation of BTO through analyzing the formation mechanism of hard aggregation. The hard aggregation of BTO was eliminated effectively when the Bi-Sn precursor (BSP) was treated with post processing including dispersing with ultrasonic wave, refluxing and distilling with addition of n-butanol and benzene (DRD) and drying by microwave. Characterized with X-ray diffraction (XRD) and transmission electron microscopy (TEM), BTO spherical particles with tetragonal phase structure are well crystallized, dispersed easily and the average size was less than 10 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
目的:研究祛瘀护膜法对反流性食管炎(RE)大鼠食管TGF-β/Smad通路及E-钙黏蛋白(E-Cadherin)表达的影响。方法:使用“4.2 mm幽门夹+2/3胃底结扎术”建立RE大鼠模型56只,造模成功后,随机分为西药组1、西药组2、治疗组、优化组、祛瘀护膜...目的:研究祛瘀护膜法对反流性食管炎(RE)大鼠食管TGF-β/Smad通路及E-钙黏蛋白(E-Cadherin)表达的影响。方法:使用“4.2 mm幽门夹+2/3胃底结扎术”建立RE大鼠模型56只,造模成功后,随机分为西药组1、西药组2、治疗组、优化组、祛瘀护膜剂组、加味祛瘀护膜剂组,每组8只,另设空白组8只。连续给药14 d,第15天采血后处死大鼠并取出食管组织。采用HE染色光镜下观察食管组织病理变化;透射电镜观察食管上皮细胞间隙;ELISA法检测转化生长因子-β1(TGF-β1)、肿瘤坏死因子-α(TNF-α)水平;RT-PCR法检测Snail m RNA、Slug m RNA、Twist m RNA、E-Cadherin m RNA表达水平;Western blotting检测TGF-β1、Snail、Slug、Twist、NLRP3、Smad2/3、p-Smad2/3蛋白表达水平;免疫组织化学染色测定TGF-β1、E-Cadherin、NLRP3表达。结果:祛瘀护膜法治疗的RE大鼠一般情况好转,体质量增加;食管黏膜损伤改善;上皮细胞间隙呈缩小趋势;食管组织中TGF-β1、Snail、Slug、Twist、NLRP3蛋白表达及Smad2/3磷酸化占比低于模型组(P<0.05),E-Cadherin蛋白及E-Cadherin m RNA表达高于模型组(P<0.05);血清中TNF-α、TGF-β1低于模型组(P<0.05)。结论:祛瘀护膜法可能通过抑制TGF-β/Smad信号通路,干预该通路介导的E-cadherin表达,促进食管炎黏膜修复,拮抗RE大鼠食管黏膜炎症。展开更多
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 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.
文摘Bismuth-doped tin dioxide (BTO) nanometer powders were prepared by the wet chemical method using tin tetrachloride (SnCl4), bismuth nitrate [Bi(NO3) 3 ] and ammonia as raw materials. Non-bridge hydroxides and capillary force between particles were found to be key factors causing hard aggregation of BTO through analyzing the formation mechanism of hard aggregation. The hard aggregation of BTO was eliminated effectively when the Bi-Sn precursor (BSP) was treated with post processing including dispersing with ultrasonic wave, refluxing and distilling with addition of n-butanol and benzene (DRD) and drying by microwave. Characterized with X-ray diffraction (XRD) and transmission electron microscopy (TEM), BTO spherical particles with tetragonal phase structure are well crystallized, dispersed easily and the average size was less than 10 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%.
文摘目的:研究祛瘀护膜法对反流性食管炎(RE)大鼠食管TGF-β/Smad通路及E-钙黏蛋白(E-Cadherin)表达的影响。方法:使用“4.2 mm幽门夹+2/3胃底结扎术”建立RE大鼠模型56只,造模成功后,随机分为西药组1、西药组2、治疗组、优化组、祛瘀护膜剂组、加味祛瘀护膜剂组,每组8只,另设空白组8只。连续给药14 d,第15天采血后处死大鼠并取出食管组织。采用HE染色光镜下观察食管组织病理变化;透射电镜观察食管上皮细胞间隙;ELISA法检测转化生长因子-β1(TGF-β1)、肿瘤坏死因子-α(TNF-α)水平;RT-PCR法检测Snail m RNA、Slug m RNA、Twist m RNA、E-Cadherin m RNA表达水平;Western blotting检测TGF-β1、Snail、Slug、Twist、NLRP3、Smad2/3、p-Smad2/3蛋白表达水平;免疫组织化学染色测定TGF-β1、E-Cadherin、NLRP3表达。结果:祛瘀护膜法治疗的RE大鼠一般情况好转,体质量增加;食管黏膜损伤改善;上皮细胞间隙呈缩小趋势;食管组织中TGF-β1、Snail、Slug、Twist、NLRP3蛋白表达及Smad2/3磷酸化占比低于模型组(P<0.05),E-Cadherin蛋白及E-Cadherin m RNA表达高于模型组(P<0.05);血清中TNF-α、TGF-β1低于模型组(P<0.05)。结论:祛瘀护膜法可能通过抑制TGF-β/Smad信号通路,干预该通路介导的E-cadherin表达,促进食管炎黏膜修复,拮抗RE大鼠食管黏膜炎症。