目的建立能同时测定冠心安口服液中蒙花苷、延胡索乙素和2,3,5,4’-四羟基二苯乙烯-2-O-β-D-葡萄糖苷含量的HPLC分析方法。方法Capcell Pak UG C_(18)色谱柱分离;蒙花苷、延胡索乙素和2,3,5,4’-四羟基二苯乙烯-2-O-β-D-葡萄糖苷检测...目的建立能同时测定冠心安口服液中蒙花苷、延胡索乙素和2,3,5,4’-四羟基二苯乙烯-2-O-β-D-葡萄糖苷含量的HPLC分析方法。方法Capcell Pak UG C_(18)色谱柱分离;蒙花苷、延胡索乙素和2,3,5,4’-四羟基二苯乙烯-2-O-β-D-葡萄糖苷检测波长分别设定为334、281、320 nm;柱温为室温;进样体积为10μL;以乙腈为流动相A,1 mL·L^(−1)磷酸溶液(三乙胺调节pH至6.0)为流动相B,梯度洗脱。结果蒙花苷、延胡索乙素和2,3,5,4’-四羟基二苯乙烯-2-O-β-D-葡萄糖苷的质量浓度分别在0.0245~2.4500、0.0457~4.5700、0.0474~4.7400μg·mL^(−1)范围内线性良好;平均回收率分别为100.8%、99.9%、101.4%;精密度和重复性RSD值(n=6)均在5.0%以内;供试品溶液在24 h内稳定。结论此方法具有前处理简单、分析时间短和检测结果准确等优点,适用于冠心安口服液制剂的质量控制。展开更多
The isotope composition in precipitation has been widely considered as a tracer of monsoon activity.Compared with the coastal region,the monsoon margin usually has limited precipitation with large fluctuation and is u...The isotope composition in precipitation has been widely considered as a tracer of monsoon activity.Compared with the coastal region,the monsoon margin usually has limited precipitation with large fluctuation and is usually sensitive to climate change.The water resource management in the monsoon margin should be better planned by understanding the composition of precipitation isotope and its influencing factors.In this study,the precipitation samples were collected at five sampling sites(Baiyin City,Kongtong District,Maqu County,Wudu District,and Yinchuan City)of the monsoon margin in the northwest of China in 2022 to analyze the characteristics of stable hydrogen(δD)and oxygen(δ18O)isotopes.We analyzed the impact of meteorological factors(temperature,precipitation,and relative humidity)on the composition of precipitation isotope at daily level by regression analysis,utilized the Hybrid Single-Particle Lagrangian Integrated Trajectory(HYSPLIT)-based backward trajectory model to simulate the air mass trajectory of precipitation events,and adopted the potential source contribution function(PSCF)and concentration weighted trajectory(CWT)to analyze the water vapor sources.The results showed that compared with the global meteoric water line(GMWL),the slope of the local meteoric water line(LMWL;δD=7.34δ^(18)O-1.16)was lower,indicating the existence of strong regional evaporation in the study area.Temperature significantly contributed toδ18O value,while relative humidity had a significant negative effect onδ18O value.Through the backward trajectory analysis,we found eight primary locations that were responsible for the water vapor sources of precipitation in the study area,of which moisture from the Indian Ocean to South China Sea(ITSC)and the western continental(CW)had the greatest influence on precipitation in the study area.The hydrogen and oxygen isotopes in precipitation are significantly influenced by the sources and transportation paths of air mass.In addition,the results of PSCF and CWT analysis showed that the water vapor source areas were primarily distributed in the south and northwest direction of the study area.展开更多
In recent years, there has been remarkable progress in the performance of metal halide perovskite solar cells. Studies have shown significant interest in lead-free perovskite solar cells (PSCs) due to concerns about t...In recent years, there has been remarkable progress in the performance of metal halide perovskite solar cells. Studies have shown significant interest in lead-free perovskite solar cells (PSCs) due to concerns about the toxicity of lead in lead halide perovskites. CH3NH3SnI3 emerges as a viable alternative to CH3NH3PbX3. In this work, we studied the effect of various parameters on the performance of lead-free perovskite solar cells using simulation with the SCAPS 1D software. The cell structure consists of α-Fe2O3/CH3NH3SnI3/PEDOT: PSS. We analyzed parameters such as thickness, doping, and layer concentration. The study revealed that, without considering other optimized parameters, the efficiency of the cell increased from 22% to 35% when the perovskite thickness varied from 100 to 1000 nm. After optimization, solar cell efficiency reaches up to 42%. The optimization parameters are such that, for example, for perovskite: the layer thickness is 700 nm, the doping concentration is 1020 and the defect density is 1013 cm−3, and for hematite: the thickness is 5 nm, the doping concentration is 1022 and the defect concentration is 1011 cm−3. These results are encouraging because they highlight the good agreement between perovskite and hematite when used as the active and electron transport layers, respectively. Now, it is still necessary to produce real, viable photovoltaic solar cells with the proposed material layer parameters.展开更多
目的 :研究南葶苈子中槲皮素 3 O β D 葡萄糖 7 O β D 龙胆双糖苷的含量测定方法 ,建立南葶苈子药材质量标准。方法 :采用反相高效液相色谱法 ,以自制标准品作对照 ,对南葶苈子药材中主要有效成分槲皮素 3 O β D 葡萄糖 7 O β D...目的 :研究南葶苈子中槲皮素 3 O β D 葡萄糖 7 O β D 龙胆双糖苷的含量测定方法 ,建立南葶苈子药材质量标准。方法 :采用反相高效液相色谱法 ,以自制标准品作对照 ,对南葶苈子药材中主要有效成分槲皮素 3 O β D 葡萄糖 7 O β D 龙胆双糖苷进行了含量测定。 结果 :回收率为 99.78% ,RSD为 2 .4 %。结论 :该方法可用于南葶苈子药材的质量控制。展开更多
依据乌鲁木齐河流域山区3个站点实测次降水δ18O和δD数据以及气象观测资料,结合临近GNIP(Global Network of Isotopes in Precipitation)站点数据,对其降水δ18O和δD特征及水汽来源进行了分析。结果表明,大气降水中δ18O值波动范围大...依据乌鲁木齐河流域山区3个站点实测次降水δ18O和δD数据以及气象观测资料,结合临近GNIP(Global Network of Isotopes in Precipitation)站点数据,对其降水δ18O和δD特征及水汽来源进行了分析。结果表明,大气降水中δ18O值波动范围大,但呈现明显的季节性变化:冬季降水δ18O较低,夏季降水δ18O较高。受流域山区气候和地理条件影响,从上游到下游各站点大气降水线截距和斜率均呈现逐渐减小趋势。大气降水中δ18O和δD与日均气温存在密切正相关关系,且温度与δ18O之间的相关性优于δD。降水中d-excess值也表现出季节性变化,冬季降水d-excess值高于夏季降水。利用HYSPLIT 4.0气团轨迹模型,得出夏季水汽主要来源西风环流输送,冬季受西风环流和极地气团共同影响。展开更多
文摘目的建立能同时测定冠心安口服液中蒙花苷、延胡索乙素和2,3,5,4’-四羟基二苯乙烯-2-O-β-D-葡萄糖苷含量的HPLC分析方法。方法Capcell Pak UG C_(18)色谱柱分离;蒙花苷、延胡索乙素和2,3,5,4’-四羟基二苯乙烯-2-O-β-D-葡萄糖苷检测波长分别设定为334、281、320 nm;柱温为室温;进样体积为10μL;以乙腈为流动相A,1 mL·L^(−1)磷酸溶液(三乙胺调节pH至6.0)为流动相B,梯度洗脱。结果蒙花苷、延胡索乙素和2,3,5,4’-四羟基二苯乙烯-2-O-β-D-葡萄糖苷的质量浓度分别在0.0245~2.4500、0.0457~4.5700、0.0474~4.7400μg·mL^(−1)范围内线性良好;平均回收率分别为100.8%、99.9%、101.4%;精密度和重复性RSD值(n=6)均在5.0%以内;供试品溶液在24 h内稳定。结论此方法具有前处理简单、分析时间短和检测结果准确等优点,适用于冠心安口服液制剂的质量控制。
基金supported by the National Natural Science Foundation of China(42161007)the Scientific Research Program for Higher Education Institutions of Gansu Province(2021B-081)the Natural Science Foundation of Gansu Province(22JR5RA074).
文摘The isotope composition in precipitation has been widely considered as a tracer of monsoon activity.Compared with the coastal region,the monsoon margin usually has limited precipitation with large fluctuation and is usually sensitive to climate change.The water resource management in the monsoon margin should be better planned by understanding the composition of precipitation isotope and its influencing factors.In this study,the precipitation samples were collected at five sampling sites(Baiyin City,Kongtong District,Maqu County,Wudu District,and Yinchuan City)of the monsoon margin in the northwest of China in 2022 to analyze the characteristics of stable hydrogen(δD)and oxygen(δ18O)isotopes.We analyzed the impact of meteorological factors(temperature,precipitation,and relative humidity)on the composition of precipitation isotope at daily level by regression analysis,utilized the Hybrid Single-Particle Lagrangian Integrated Trajectory(HYSPLIT)-based backward trajectory model to simulate the air mass trajectory of precipitation events,and adopted the potential source contribution function(PSCF)and concentration weighted trajectory(CWT)to analyze the water vapor sources.The results showed that compared with the global meteoric water line(GMWL),the slope of the local meteoric water line(LMWL;δD=7.34δ^(18)O-1.16)was lower,indicating the existence of strong regional evaporation in the study area.Temperature significantly contributed toδ18O value,while relative humidity had a significant negative effect onδ18O value.Through the backward trajectory analysis,we found eight primary locations that were responsible for the water vapor sources of precipitation in the study area,of which moisture from the Indian Ocean to South China Sea(ITSC)and the western continental(CW)had the greatest influence on precipitation in the study area.The hydrogen and oxygen isotopes in precipitation are significantly influenced by the sources and transportation paths of air mass.In addition,the results of PSCF and CWT analysis showed that the water vapor source areas were primarily distributed in the south and northwest direction of the study area.
文摘In recent years, there has been remarkable progress in the performance of metal halide perovskite solar cells. Studies have shown significant interest in lead-free perovskite solar cells (PSCs) due to concerns about the toxicity of lead in lead halide perovskites. CH3NH3SnI3 emerges as a viable alternative to CH3NH3PbX3. In this work, we studied the effect of various parameters on the performance of lead-free perovskite solar cells using simulation with the SCAPS 1D software. The cell structure consists of α-Fe2O3/CH3NH3SnI3/PEDOT: PSS. We analyzed parameters such as thickness, doping, and layer concentration. The study revealed that, without considering other optimized parameters, the efficiency of the cell increased from 22% to 35% when the perovskite thickness varied from 100 to 1000 nm. After optimization, solar cell efficiency reaches up to 42%. The optimization parameters are such that, for example, for perovskite: the layer thickness is 700 nm, the doping concentration is 1020 and the defect density is 1013 cm−3, and for hematite: the thickness is 5 nm, the doping concentration is 1022 and the defect concentration is 1011 cm−3. These results are encouraging because they highlight the good agreement between perovskite and hematite when used as the active and electron transport layers, respectively. Now, it is still necessary to produce real, viable photovoltaic solar cells with the proposed material layer parameters.
文摘目的 :研究南葶苈子中槲皮素 3 O β D 葡萄糖 7 O β D 龙胆双糖苷的含量测定方法 ,建立南葶苈子药材质量标准。方法 :采用反相高效液相色谱法 ,以自制标准品作对照 ,对南葶苈子药材中主要有效成分槲皮素 3 O β D 葡萄糖 7 O β D 龙胆双糖苷进行了含量测定。 结果 :回收率为 99.78% ,RSD为 2 .4 %。结论 :该方法可用于南葶苈子药材的质量控制。
文摘依据乌鲁木齐河流域山区3个站点实测次降水δ18O和δD数据以及气象观测资料,结合临近GNIP(Global Network of Isotopes in Precipitation)站点数据,对其降水δ18O和δD特征及水汽来源进行了分析。结果表明,大气降水中δ18O值波动范围大,但呈现明显的季节性变化:冬季降水δ18O较低,夏季降水δ18O较高。受流域山区气候和地理条件影响,从上游到下游各站点大气降水线截距和斜率均呈现逐渐减小趋势。大气降水中δ18O和δD与日均气温存在密切正相关关系,且温度与δ18O之间的相关性优于δD。降水中d-excess值也表现出季节性变化,冬季降水d-excess值高于夏季降水。利用HYSPLIT 4.0气团轨迹模型,得出夏季水汽主要来源西风环流输送,冬季受西风环流和极地气团共同影响。
