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高效液相色谱法测定虎杖中自藜芦醇,白藜芦醇苷和游离大黄素 李来生1,杨汉荣1,陈雄泉1 (1.南昌大学分析测试中心,南昌,330047) 摘要:用高效液相色谱法同时测定虎杖中白藜芦醇,白藜芦醇苷和游离大黄素含量.色谱柱为Waters Symmetry C18柱(3.9 mm×150 mm,5μm),流动相为0.015 mol-1 H3PO4-甲醇,流速为0.5 mL·min-1,检测波长为284nm.样品采用乙醇-水(1+1)溶液和乙酸乙酯提取.江西产虎杖样品中白藜芦醇,白藜芦醇苷和游离大黄素的回收率分别为97.9%,96.1%,95.6%,相对标准偏差小于5%. 关键词:高效液相色谱法; 梯度淋洗; 虎杖; 白藜芦醇; 白藜芦醇苷; 游离大黄素; [全文内容正在添加中] ......
反相高效液相色谱法测定鬼灯檠中岩白菜素的含量 李多伟1,陈俐宏1,王凡1,郭培莹1,任静1 (1.西北大学,生命科学学院,西安,710069) 摘要:建立了反相高效液相色谱法测定鬼灯檠中岩白菜素的含量.色谱柱为Symmetry C18柱(5 μm,4.6 mm×150 mm),流动相为甲醇-水(1:3),流速为1.0 mL·min-1,柱温30±1 ℃,检测波长为275 nm.该方法线性范围为0.8~4.0 μg(r=0.998 7),平均加标回收率为100.5%,岩白菜素的相对标准偏差为1.6%(n=6),检出限为0.1 ng.方法快速,简单,灵敏度高. 关键词:反相高效液相色谱法; 鬼灯檠; 岩白菜素; [全文内容正在添加中] ......
反相高效液相色法测定水产品中三聚氰胺覃东立1,战培荣1,陈中祥1,孙平21. 中国水产科学研究院黑龙江水产研究所2. 黑龙江省农垦总局疾病预防控制中心摘 要:采用反相高效液相色谱法(RP-HPLC)测定了水产品中的三聚氰胺.色谱柱为Symmetry C18(5μm,4.6 mm×250 mm),流动相为含有0.01 mol/L庚烷磺酸钠和0.01 mol/L柠檬酸的乙腈(1+4)水溶液,检测器为紫外检测器,检测波长240 nm.线性范围为150μg/mL,相关系数为0.9998,最低检出限为0.24μg/mL,样品平均加标回收率为78.8%96.1%,相对标准偏差为3.7%6.4%.方法可用于水产品中三聚氰胺的测定.关键词:三聚氰胺;水产品;反相高效液相色谱法;......
lattice influenced the symmetry types of NaYF4 crystals,resulting in phase transformation of NaYF4 crystals between α and β phase.The pure hexagonal phase of branched NaYF4:Eu3+ was obtained......
symmetry). Magnetic studies indicated the existence of antiferromagnetic interaction in complexes 1–3.关键词:......
by thin hydroxide layer.Size of the nanoparticles is controlled by temperature of calcination.1200℃heating causes drop of luminescence intensity,explained as damage of high symmetry surface emission......
lattice influenced the symmetry types of NaYF4 crystals,resulting in phase transformation of NaYF4 crystals between α and β phase.The pure hexagonal phase of branched NaYF4:Eu3+ was obtained......
symmetry). Magnetic studies indicated the existence of antiferromagnetic interaction in complexes 1–3.关键词:......
by thin hydroxide layer.Size of the nanoparticles is controlled by temperature of calcination.1200℃heating causes drop of luminescence intensity,explained as damage of high symmetry surface emission......
alloy. It is well known that the diffraction pattern showing 5-fold symmetry is typical for the icosahedral quasicrystalline structure [10,22], and the I-phase (Mg30Zn60Er10) is found in Mg-Zn-Er alloy [16]. Figure 3(b) shows the SAED pattern of the I-phase with its 5-fold symmetry. Besides, the SAED patterns of the I-phase with 3-fold symmetry and 2-fold symmetry are observed, as seen in Figs. 3(c......