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Stylus-based surface profiling is a standard technique for accurate, repeatable surface shape, topography and step height measurement in applications ranging from semiconductor R&D to solar cell QC.

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

抗氧化剂是指能防止或延缓食品氧化，提高食品的稳定性和延长贮存期的食品添加剂。GB5009.32-2016《食品安全国家标准 食品中9种抗氧化剂的测定》中采用GPC和C18小柱对食品中9种抗氧化剂进行前处理，该方法回收率低，测试结果不稳定。安谱实验优化了实验方法，用CNW Poly-Sery PSD SPE小柱进行前处理，克服了国标方法的缺点，方法简单，9种抗氧化剂的回收率均在90%以上。

Ramina过程分析仪为离线手动或自动湿态化学测试提供了一种快速且易于操作的替代方案。相比于传统的拉曼过程监控系统，它的安装和使用变得更加简单。Ramina为用户开始收集数据提供了所需的全部设备，包括拉曼光谱仪和光纤探针，以及便携式监视器、鼠标、键盘和激光安全护目镜。工厂校准可确保Ramina系统随时能够投入使用，其固态结构提供了长期稳定性。这意味着用户可以进行连续、高精度的测量，而无需频繁校准。用户还可以并联使用多个系统来同时测试不同的反应容器，或者在一个反应容器中组合使用多个探针。