顶空毛细管气相色谱法测定茶多酚中有机溶剂的残留量

文献名： Structural, morphological and optical properties of Bi NPs obtained by laser ablation and their selective detection of L-cysteine 作者： Ramon Gabriel Teixeira Rosaa, Celso de Araujo Duartea , Wido Herwig Schreinera, Ney Pereira Mattoso Filhoa, Arandi Ginane Bezerra Jr.b, Andersson Barisonc, Fernanda Maria Marins Ocamposc a Departamento de Física, Universidade Federal do Paraná Centro Politécnico, CP 19044, 81531-990 Curitiba (PR), Brazil b Departamento Acadêmico de Física, Universidade Tecnológica Federal do Paraná, 80230-901 Curitiba (PR), Brazil c Departamento de Química, Universidade Federal do Paraná Centro Politécnico, CP 19081, 81531-990 Curitiba (PR), Brazil 摘要：In the present work we show the results of the investigation of the properties of bismuth nanoparticles (NPs) obtained by the laser ablation in water. The samples were characterized by various techniques: UV/vis spectroscopy, dynamic light scattering, transmission electron microscopy, X-ray photoelectron spectroscopy, X-ray diffraction, nuclear magnetic resonance and zeta potential. The NPs were metallic and surface oxidated, exhibiting absorption peak at 257 nm due to the surface plasmon resonance. The interaction between the NPs and various amino acids was studied and revealed a selective sensibility to cysteine on a range of concentration from 80 to 720 μM, which we attribute to a dimerization of cysteine to cystine probably complexed to the nanoparticle surface by electrostatic interactions, leading to the modification of the NP absorption spectrum. 关键词：Bismuth; Nanoparticles; Laser ablation; Cysteine

市面上有众多的新冠病毒qPCR检测试剂盒，本应用方案采用韩国Seegene公司的AllplexTM 2019-nCoV检测试剂盒在耶拿荧光定量PCR仪 qTOWER³G上进行样品检测，获得符合预期的结果。

磷酸中杂质的监测对于其应用至关重要。除其它参数外，总有机碳还作为总量参数应用于质量控制中，用于评估有机杂质的整体污染情况。 本文主要对紫外-过硫酸盐氧化法和NDIR检测器对磷酸中TOC杂质的全自动质量控制进行验证。

Thermo Scientific针对空气敏感样品开发了惰性气体/真空保护样品传输系统CleanConnect，为空气敏感材料表征开拓出了全新视野。惰性气体/真空保护样品转移工作流程能够帮助科研工作者拓展空气敏感材料的研究边界，探究更多未知领域。