2016/05/24 15:20
阅读:43
分享:方案摘要:
产品配置单:
GC5890N气相色谱仪
型号: GC5890N
产地: 江苏
品牌: 南京科捷
¥3万 - 5万
参考报价
联系电话
方案详情:
在富营养化水体中,一些藻、菌微生物群落过剩生长,它们能不断分泌和产生出各种具有异味的次生代谢产物,其中以具有土霉味的2-甲基异茨醇、土腥素和具有草木腥味的β-柠檬醛最为常见,其结构见图。
10ng/L异味化合物就可能使水质与水产品产生刺鼻难闻的异味,导致饮用水水质下降,致使水处理耗费大幅增加,渔业经济直接遭受损失以及大大减少人类消遣和旅游地区的美学价值等。
随着我国湖泊富营养化过程的加剧,水及水产品异味问题也日益严重,因此,建立水中痕量异味化合物的灵敏可靠的分析方法对于我国开展水体异味研究和解决水体异味问题具有十分重要的意义。
目前,国内外对水体异味的检测方法可分为两类,即嗅觉鉴定法和仪器分析法。我国国标中对水样的臭和味的检验只采用嗅觉 法,该法存在难以准确划分异味的类型并无法测定低于嗅觉阈值的异味化合物的缺点;仪器分析法则是先采用不同的前处理方法,如蒸汽蒸馏萃取法、液-液萃取法、吹扫捕集法、闭环捕集法、开环捕集法及固相微萃取法提取异味化合物后,再用气相色谱法分析。但上述方法各有缺点,如:样品需要量大,耗费有机溶剂,操作复杂,灵敏度低,难以测定痕量(ng/L级)的异味化合物。
而应用顶空固相微萃取法(HS-SPME)富集异味化合物,采用顶空进样器、气相色谱-质谱联用仪检测优化了纤维头的类型、盐的浓度、萃取的温度和时间等条件,结合GC-MS对水中痕量的异味化合物进行了测定,可获得满意结果。该法应用于微囊藻的异味性次生代谢产物β-柠檬醛的定量分析,为研究蓝藻水华导致的水体异味问题提供了有效的分析方法。
下载本篇解决方案:
更多
台阶仪在三维形貌表征领域的应用
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.
2008/12/15
YSI防玷污的10个技巧
YSI 防玷污的10点技巧 随着电子技术的进步、电源管理的改进和电池寿命的延长,生物玷污成为目前决定监测仪器投放周期长度的决定因素,特别是应用于长期、连续监测。应用一些防玷污技术可以延长仪器的维护间隔,能够减少野外的仪器维护的次数,并提高水质监测数据精度。 防玷污技巧的详细内容请参考文章《YSI 防玷污的10点技巧》
环保
2014/03/04
NanoBrook产品应用-12-ZetaPALS
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
2015/04/16
4D-脂质组学高通量工作流程
Lipid profiling from complex lipid extracts can be a challenging and time consuming task. The high complexity of samples and co-elution of isobaric or isomeric compounds complicate the confident annotation of lipids. The presented 4D-Lipidomics workflow simplifies and streamlines the annotation and validation process using mobility-enhanced MS data.
医疗/卫生
2021/03/05