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锂离子选择性微电极在生物体液中的响应 总被引:2,自引:0,他引:2
最近几年已报道了几种锂离子选择性电极.本文作者曾研制了以苯基膦酸二辛酯(DOPP)为溶剂,四苯硼酸盐为活性物质的PVC膜锂离子选择电极.本文在此基础上研制了锂离子选择性微电极,比较了以四苯硼酸钾(KTPB)及四苯硼酸钠(NaTPB)为活性物质的锂微电极的性能.同时考察了微电极在细胞内液、血清及生理盐液中对锂离子的响应特性. 相似文献
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PreparationandCrystalStructureofPrNb_5O_(14)¥MaoJiang-Gao;ZhuangHong-Hui;HuangJin-Shun(StateKeyLaboratoryofStructuralChemistry... 相似文献
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A very sensitive electroanalytical method was employed to determine bergenin in phosphate buffer with a pH of 6.0, bergenin was accumulated at a 4-(2-pyridylazo)-resorcinol (PAR) polymer film modified glassy carbon electrode (GCE) surface under the condition of open-circuit. In the following anodic sweep from −0.4 to 0.8 V, bergenin adsorbed at the PAR polymer film modified electrode surface, was oxidized and yielded a sensitive oxidation peak at 0.595 V. Due to its unique structure and extraordinary properties, the PAR polymer film shows higher accumulation efficiency toward bergenin compared with a bare GCE. Hence, the amount of bergenin at the PAR polymer film modified GCE surface increases significantly, and finally the oxidation peak current improves greatly. The experimental conditions, such as supporting electrolyte, pH value, accumulation time and scan rate, were optimized for the measurement of bergenin, and a sensitive electroanalytical method was proposed for bergenin determination. The oxidation peak current varies linearly with the concentration of bergenin over the range of 2.0 × 10−7 to 1.2 × 10−5 mol/L, and the detection limit is 2.0 × 10−8 mol/L after 3 min open-circuit accumulation. The relative standard deviation of the same electrode in 10 successive scans is 1.8% for 1.0 × 10−6 mol/L bergenin and 2.1% for interelectrodes, indicating excellent reproducibility. This new method was successfully demonstrated with bergenin tablets and diluted urine. 相似文献
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Studyofthegrowthprocessofcolloidalparticlesofnonequilibriumandirreversibilityisanactiveareaofresearch.Therecognitionofcolloidalaggregatesasfractalobjectshasinspiredalargenumberofexperimentalandtheoreticalstudiesonthestructuralandkineticaspectsofaggregationprocesses"'.Morerecently,kineticsofhematiteaggregationbypolyacrylicacidhavebeenstudiedbyzhangandBume3.Theprimaryhematiteparticleswerequiteuniformandfairlyspherical.Inthispaper,wewillreportthesizeevolutionoffractalaggregatesofinitiallypolydis… 相似文献
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A simple method is developed to synthesize gram quantities of uniform Ge nanowires (GeNWs) by chemical vapor deposition on preformed, monodispersed seed particles loaded onto a high surface area silica support. Various chemical functionalization schemes are investigated to passivate the GeNW surfaces using alkanethiols and alkyl Grignard reactions. The stability of functionalization against oxidation of germanium for various alkyl chain lengths is elucidated by X-ray photoelectron spectroscopy. Among all schemes tested, long chain alkanethiols (> or = C12) are found to impart the most stable GeNW passivation against oxidation upon extended exposure to ambient air. Further, the chemically functionalized oxidation-resistant nanowires are soluble in organic solvents and can be readily assembled into close-packed Langmuir-Blodgett films potentially useful for future high performance electronic devices. 相似文献
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Yizhao Ouyang Miao Zhan Jing Zhou Jiao Jiao Hao Hu Yoichi M. A. Yamada Pengfei Li 《中国化学》2019,37(8):807-810
A rigid C2‐symmetric chiral bipyridine ligand Z‐bpy with a triptycene‐like backbone was designed and synthesized from simple chemicals in a scalable route. Using this new ligand, copper(I) catalyzed cyclopropanation of styrenes with commercial ethyl diazoacetate produced various corresponding cyclopropanes in high yields, diastereoselectivity and enantioselectivity up to 97% ee. 相似文献
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