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1.
基于在碱性条件下,银杏黄酮对ClO--鲁米诺体系有显著的抑制作用,结合反相流动注射技术,建立了流动注射-抑制化学发光测定银杏提取物中的银杏黄酮.银杏黄酮质量浓度在0.4~14.0 μg/mL范围与相对发光强度呈线性关系,检出限为0.06 μg/mL,采样频率为120次/h,对10.0 μg/mL的银杏黄酮平行测定11次,其RSD为1.2%,回收率为98.0%~104%.该方法可用于银杏黄酮制剂的测定.  相似文献   

2.
基于在碱性条件下,银杏黄酮对CIO^--鲁米诺体系有显著的抑制作用,结合反相流动注射技术,建立了流动注射.抑制化学发光测定银杏提取物中的银杏黄酮。银杏黄酮质量浓度在0.4~14.0μg/ML范围与相对发光强度呈线性关系,检出限为0.06μg/ML,采样频率为120次/h,对10.0μg/ML的银杏黄酮平行测定11次,其RSD为1.2%,回收率为98、0%~104%。该方法可用于银杏黄酮制剂的测定。  相似文献   

3.
原子吸收法间接测定银杏黄酮   总被引:3,自引:0,他引:3  
提出了间接测定银杏叶精提物中银杏黄酮的原子吸收光谱法。银杏黄酮与乙酸铅发生配合反应,生成难溶的棕黄色沉淀,经离心分离后,用原子吸收法测定上清液中过量的铅离子,可间接测定银杏黄酮。方法线性范围为5.0~30.0μg mL,RSD为1.6%~1.8%,回收率为100.3%~106.0%。  相似文献   

4.
基于在B-R缓冲溶液介质中,Sb(Ⅲ)对H2O2氧化孔雀石绿褪色反应具有催化作用,建立了流动注射催化动力学光度法测定微量元素Sb(Ⅲ)的新分析方法,该方法的线性范围为0.010~2.0μg/mL,检出限为7.8×10-3μg/mL,r=0.9996。对0.1μg/mL Sb(Ⅲ)测定的RSD=0.97%n=11,进样频率为22.8次/h。用于环境水样中微量Sb(Ⅲ)的测定,回收率为97.3%~97.7%。  相似文献   

5.
自行研制了一套流动比色装置,进行了双光束流动注射分析光度法的应用研究.基于二溴羟基苯荧光酮(DBHPF)与钴形成紫色络合物的原理,提出了一种新的流动注射微分测试技术,方法进样速度为110~120次/时,浓度在0~0.6μg/mL呈良好的线性关系.对0.3μg/mL的Co(Ⅱ)连续11次进样平行测定相对标准偏差为1.2%.用于食品中微量钴的测定,结果满意.  相似文献   

6.
基于在碱性条件下,蒽醌对ClO- Luminol化学发光体系的显著抑制作用,结合反向流动注射技术,提出了蒽醌的流动注射 化学发光分析新方法。蒽醌的质量浓度在0.5~100μg mL范围内与化学发光的抑制强度呈良好的线性关系。检出限为0.05μg mL,RSD=1.6%,采样频率为150次 h,回收率为105%~107.5%。  相似文献   

7.
微波溶样流动注射分光光度法在线测定金矿石中的金   总被引:5,自引:0,他引:5  
采用微波溶样 流动注射在线泡塑富集分离 分光光度联用技术建立了在线快速测定金矿石中金的方法。比较了微波溶样法与传统电热板溶样法,二者结果基本一致。前者溶样时间近似为后者的1 9。确定了两条工作曲线:校正曲线范围为0 1~1.0μg mL,检出限2.2×10-2μg mL;校正曲线范围为1.0~9 0μg mL,检出限1.6×10-1μg mL。FI SP系统分散系数为3.78。对管理样GBW(E) 070014平行11次测定,其RSD为1.3%,对所得结果进行t检验,置信度95%时,无系统误差存在。  相似文献   

8.
提出了流动注射-抑制化学发光测定银杏叶中的总黄酮含量的分析方法.它是基于银杏叶中物质黄酮类具有还原性,在碱性条件下还原H_2O_2,抑制鲁米诺-H_2O_2-KIO_4体系的化学发光,其抑制程度的大小与总黄酮的含量成线性关系.方法的线性范围为1.5~30μg/mL,检出限为0.03μg/mL,相对标准偏差(RSD)为1.2%,采样频率为240次/h,回收率为101%~104%.  相似文献   

9.
流动注射化学发光法测定头孢氨苄和头孢拉定   总被引:13,自引:0,他引:13  
基于KMnO4在酸性介质中氧化头孢氨苄和头孢拉定产生微弱的化学发光,同时借助甲醛对发光的增强作用,采用流动注射技术,建立了以上两种头孢类抗生素药物的测定新方法。方法检出限分别为0.096和0.10μg mL;相对标准偏差分别为1.6%和1.8%(n=11),线性范围分别为0.8~25和0.8~32μg mL,进样频率为60次 h。本方法已用于药物制剂的测定。  相似文献   

10.
基于亚硫酸盐在碱性条件下与碱性品红的褪色反应,建立了流动注射光度分析测定食品中亚硫酸盐的新方法.在38样/h采样频率下检出限为0.016μg/mL,SO32-质量浓度在0.04~1.5 μg/mL范围符合朗伯比耳定律,测定1.2μg/mL SO32- 11次,相对标准偏差为0.41%.该法可用于食品中亚硫酸盐的测定.  相似文献   

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Oxidation of fully substituted imidazoles 1 by singlet oxygen gives in good yield fully substituted 2-hydroperoxy-2H-imidazoles 2 . Reduction of 2 by triphenylphosphine leads to 2-hydroxy-2H-irnidazoles 3 . Limitations of the methods are reported.  相似文献   

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15.
[(n‐Bu)2Sn(O2PPh2)2] ( 1 ), and [Ph2Sn(O2PPh2)2] ( 2 ) have been synthesized by the reactions of R2SnCl2 (R=n‐Bu, Ph) with HO2PPh2 in Methanol. From the reaction of Ph2SnCl2 with diphenylphosphinic acid a third product [PhClSn(O2PPh2)OMe]2 ( 3 ) could be isolated. X‐ray diffraction studies show 1 to crystallize in the monoclinic space group P21/c with a = 1303.7(1) pm, b = 2286.9(2) pm, c = 1063.1(1) pm, β = 94.383(6)°, and Z = 4. 2 crystallizes triclinic in the space group , the cell parameters being a = 1293.2(2) pm, b = 1478.5(4) pm, c = 1507.2(3) pm, α = 98.86(3)°, β = 109.63(2)°, γ = 114.88(2)°, and Z = 2. Both compounds form arrays of eight‐membered rings (SnOPO)2 linked at the tin atoms to form chains of infinite length. The dimer 3 consists of a like ring, in which the tin atoms are bridged by methoxo groups. It crystallizes triclinic in space group with a = 946.4(1) pm, b = 963.7(1) pm, c = 1174.2(1) pm, α = 82.495(6)°, β = 66.451(6)°, γ = 74.922(6)°, and Z = 1 for the dimer. The Raman spectra of 2 and 3 are given and discussed.  相似文献   

16.
Summary The ability of [MoS4]2–, anions to be used as ligands for transition metal ions has been widely demonstrated, especially with Fe2+. The present study has been restricted to linear complexes such as (NEt4)2 [Cl2FeS2MoS2] and (NEt4)2[Cl2FeS2MoS2FeCl2]. Their electrochemical properties are described: upon electrochemical reduction, these compounds yield MoS2, as a black precipitate, and an iron complex in solution, assumed to be [SFeCl2]2–. The electrochemical reduction goes through two electron transfers, coupled with the breakdown of the molecular skeleton: a DISPl and an ECE mechanism. Depending on the solvent, the following equilibrium may be observed: [Cl4Fe2MoS4]2–[Cl2FeMoS4]2–+FeCl2. The equilibrium constant, KD, was evaluated by differential pulse polarography. KD is tightly related to the donor number of the solvent.  相似文献   

17.
Irradiation of 5,5-dimethyl-6-oxocyclohex- l-ene- l-carbonitrile ( 1 ) in the presence of 2,3-dimethylbut-2-ene afforded 3,3,4,4,7,7-hexamethyl-3,4,4a,5,6,7-hexahydroindeno[1,7-c,d]-],2-oxazole (3) in nearly quantitative yield. In contrast, 4,4-dimethyl-5-oxo-cyclopent-l-ene-l-carbonitrile ( 2 ) under the same conditions reacted not to a tricyclic isoxazole but to a 2:1 mixture of 3,3,6,6,7,7-hexamethyl-2-oxo-bicyclo[3.2.0]heptane-l-carbonitrile ( 4 ) and trans-3,3-dimethyl-2-oxo-5-(2,3-dimethylbut-3-en-2-yl)cyclopentane-l-carbonitrile ( 5 ), respectively.  相似文献   

18.
TG and DTA studies on Me3SnO2PCl2, Me2Sn(O2PCl2)2 and Ph3SnO2PCl2 were carried out under dynamic argon atmosphere. The results show that the decomposition proceeds in different stages leading to the formation of Sn3(PO4)2 as a stable product. This compound was characterized by IR spectroscopy. Decomposition schemes involving reductive elimination reactions were proposed.  相似文献   

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Alkylation and oxidation of 2H-2-imidazolines, followed by regioselective deprotection, thionation and microwave-assisted Liebeskind-Srogl reaction, efficiently led to 2-aryl-2-imidazolines as new analogues of p53-hdm2 interaction inhibitors (Nutlins).  相似文献   

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