啤酒分析资料

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。

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。

2022年3月15日，国家市场监督管理总局（国家标准化管理委员会）批准了新版《生活饮用水卫生标准》（GB5749-2022），该标准将于2023年4月1日起正式施行，全部代替现行的GB5749-2006。在新版国家标准中水质指标由原来的106项调整为97项，包括常规指标43项和扩展指标54项；水质参考指标由原来的28项调整为55项。北京宝德仪器有限公司现有产品可帮助用户解决14项常规指标、4项扩展指标和4项水质参考指标的测定。