新一代绿色表面活性剂--APG

介绍了新一代绿色表面活性剂APG的结构和性质,并重点阐述了它的合成、衍生物及其应用,分析了它的市场前景。     

分析科学中的综合分析—剖析技术进展

本文从分析方法和应用两方面，对分析科学中的一个重要分叉－剖析技术予以综合介绍。从方法论看剖析，它充分体现了分析科学综合性的特点、集分离分析、结构分析和成份分析于一体，全面表征物质的结构和成份信息；从应用方面看，它囊括无机，有机，物化和生化等领域中的分析课题，以材料科学、生命科学和环境科学中的各种复杂样品的分析，因此剖析又是把分析科学与合成，加工和应用技术紧密联系的一种系统工程。它的学科地位和广泛的     

柏拉图多面体与高碳原子簇

在简要分析柏拉图多面体的对称性质和几何特性的基础上,讨论了它与一般高对称性原子簇的分子骨架几何构型,特别是它与高对称性高碳原子簇几何构型之间的关系.     

纳米金标记分析

金纳米粒子是一种性能优异的标记物,在光分析和电分析中应用广泛.综述了它在核酸、蛋白质和生物分子检测中的应用及发展趋势.     

人工水晶-X面上的巴西双晶及其形成机制

在人工水晶的-X面{1120}上常可观察到凸起的微小晶状物,作者利用光学和电子光学等方法, 经分析鉴定确认它为巴西双晶(光学双晶),并根据其结晶形态分析了它的结晶习性。     

荧光偏振免疫分析技术的研究进展

对荧光偏振免疫分析技术的研究进展作了详细的评述。介绍了荧光偏振免疫分析技术的基本原理和研究热点,评述了它在临床检验、环境与食品监测和农药残留量分析等领域中的应用,对荧光偏振免疫分析方法的优缺点作了总结,引文献45篇。     

PVC基管状流通钾离子选择电极的研制及其在流动注射分析中的应用

实验装置由PVC基管状流通钾离子选择电极和与它结合的流动注射分析体系两部分组成。对该体系的分析特点和影响测定的参数进行了讨论,建立了土壤浸提液中钾测定方法,样品分析结果和火焰光度法有良好一致性。     

一种新的发射光谱光源辉光放电灯的研制

自从一九六七年Grimm设计了一种结构特殊的辉光放电灯作为发射光谱分析的光源以来,辉光放电光源逐渐引起光谱分析工作者的注意和研究。这种光源的取样和激发机理与惯用的电弧、火花等光源有所不同。它稳定性好,共存元素影响小,谱线自吸收小,并且能对试样表面逐层地取样分析。这使它在高含量合金成份的分析和表层分析方面显示出较大的优越性。我们已研制出这种光源,对它的工作参数、性能及其相互关系进行了初步研究,并与摄谱法配合作了金属表层逐层分析,效果较好。一、设备全部设备由辉光灯、供气系统和稳压电源三部分组成。     

五氧化二磷使乙醇脱水的实证探索与反思

通过实验探究和文献分析,说明五氧化二磷具有强脱水性,它与乙醇反应生成磷酸氢乙酯和磷酸二乙酯,不是乙醇脱水的催化剂,分析了造成人们错误认识的原因。     

高分子化学试题库系统的开发

利用当前通行的关系数据库技术、采用VB编程语言和ACCESS数据库 ,设计了高分子化学教学试题库系统应用软件———“试卷魔术师”。它由四个模块组成 ,即试题库模块、试卷分析模块、资料库模块和辅助模块。具有试题的录入、删除、修改和访查、手工或自动生成试卷、试卷分析以及资料查阅等诸多功能。满足授权的用户可以利用它随机抽卷、查阅相关资料及历史成绩等。它不仅可以作为高分子化学课程教师生成试卷、分析试卷的有力工具 ,又可作为本专业学生进行高分子化学试题训练、自学并阅读课外参考资料的有效手段。它使用方便 ,操作简单 ,针对性强 ,是一种较为实用的计算机辅助教学软件工具     

核酸适配体生物传感器在三聚氰胺检测中的应用进展

三聚氰胺常被非法添加到食品中,以提高食品中蛋白质的含量。但是,三聚氰胺一旦进入体内,会对人们的健康造成伤害。因此,对三聚氰胺的检测十分必要。为了弥补传统仪器检测法和免疫检测法的不足,基于核酸适配体开发了一系列新的生物传感器,用于三聚氰胺的检测。按照与三聚氰胺的不同识别机制,把这些新的生物传感器分成了四类,分别为基于多聚胸腺嘧啶DNA链和三聚氰胺识别的生物传感器、基于无嘌呤位点的三链DNA结构和三聚氰胺识别的生物传感器、基于核酸适配体和三聚氰胺识别的生物传感器、基于三聚氰胺和汞离子/铜离子等配位识别的生物传感器。本文按照上述四类方法逐个展开,对核酸适配体生物传感器在三聚氰胺检测中的应用进行了综述,并对它们的优缺点进行阐述。     

Vibrational spectra of melamine diborate,C3N6H62H3BO3

IR and Raman spectra of melamine diborate have been recorded and analysed. Band assignments are given based on the vibrations of melamine and boric acid molecules. Three sets of frequencies observed for the N-H stretching mode region is ascribed to different types of hydrogen bonds in the amino groups of the triazine ring. Due to the lower symmetry of the melamine and boric acid molecules in the crystal, activation of inactive modes and lifting of the degeneracy of certain vibrational modes are observed. Lower symmetry of the melamine molecule in the crystal has resulted in the decrease of intensity of the Raman active melamine band around 1490 cm(-1). All the internal modes of boric acid molecule were identified. All the ring breathing modes of melamine molecule show frequency shift towards the high wavenumber side. In other words, hydrogen bonding affects the ring breathing modes of melamine.     

Colorimetric recognition of melamine in milk using novel pincer zinc complex stabilized gold nanoparticles

A convenient colorimetric approach for visual detection of melamine in raw milk was realized by using gold nanoparticles (AuNPs) stabilized by an unsymmetrical terpyridyl zinc complex with a thymine fragment at one terminal and a quaternary ammonium salt at the other. Even without pre-addition of melamine or relative additives, obvious color change from red to blue was observed by naked eye in the presence of trace amount of melamine, which was attributed to the alternation of aggregation state of AuNPs caused by the selective binding between the thymine fragment and melamine via triple hydrogen-bonding interactions. Remarkably, the detection limit for melamine was as low as 2.4 ppb, providing a highly sensitive and efficient approach for the visual detection of melamine.     

固相萃取-表面增强拉曼光谱法测定奶粉中三聚氰胺

建立了固相萃取-表面增强拉曼光谱法(SPE-SERS)测定奶粉中三聚氰胺的分析方法。待测物经乙腈提取、活性碳吸附及氢氧化钠溶液洗脱后进行SERS检测。该方法的线性范围为0.005 0~1.6 mg/L,检出限为0.100 mg/kg,回收率为75.3%~125%,相对标准偏差(RSD,n=5)不大于9.3%。该法灵敏度高、杂质干扰小、结果准确可靠,能满足奶粉中三聚氰胺的快速检测,在奶粉质量监控方面具有良好的应用潜力。     

Monitoring of melamine contamination in fat watery milk by the photoluminescence analysis

A photoluminescence method to detect the toxic melamine contamination in fat watery milk has been proposed. Despite the quite different luminescence origins of milk and melamine patterns, their wide emission spectra under UV excitation are similar and in the range of 2.2-3.5 eV. The complex milk photoluminescence spectrum composed of riboflavin, furosine, lactulose, Vitamin E and tryptophan emitting species can be modified if milk pattern is undergone by acid treatment (for example, in vinegar). At the same time the melamine emission is not subjected to any modification in vinegar. It allows quantitatively discriminating the melamine contamination in milk in linear range, at least, 0.05-7 g/l from different photoluminescence spectra of milk (water) with and without melamine. Limit of melamine detection achieves 0.01 g/l.     

Integrated photografted molecularly imprinted polymers with a cellulose acetate membrane for the extraction of melamine from dry milk before HPLC analysis

In this study, a new separation technique based on membrane extraction is described for the determination of melamine in dry milk. The water‐compatible cellulose acetate membrane, which is photografted by melamine imprinted nanospheres, was prepared by placing the membrane into the polymerization solution containing methacrylic acid as a functional monomer, ethylene glycol dimethacrylate as cross‐linker, acetonitrile as porogen, and melamine as the template molecule. The characterization of the polymeric membrane was performed by Fourier transmission infrared spectroscopy and scanning electron microscopy. This integrated composite membrane was used as a solid‐phase extraction medium for the extraction of melamine from dry milk samples. Various parameters affecting the extraction efficiency of the membrane were evaluated. The results showed higher binding capacity for melamine imprinted membranes in comparison with the nonimprinted membranes. High‐performance liquid chromatography analysis showed that the extraction of melamine from dry milk by the photografted cellulose acetate membrane had a linear calibration curve in the range of 0.02–11.80 μg/mL with an excellent precision of 2.73%. The limit of detection and quantification of melamine was 0.007 and 0.020 μg/mL, respectively. The recoveries of melamine were in the range of 88.7–94.8%.     

化学发光法测定奶粉中的三聚氰胺

在碱性条件下,三聚氰胺对鲁米诺-铁氰化钾体系化学发光反应具有明显的增敏作用;据此建立了流动注射化学发光测定奶粉中三聚氰胺的分析方法,确定了优化测定条件,并将该方法用于测定奶粉中的三聚氰胺.结果表明,在优化测定条件下,三聚氰胺的质量浓度在1.0×10-6～4.0×10-5 g.L-1范围内与发光强度呈现良好的线性关系,检出限为2.6×10-7 g.L-1,11次平行测定4.0×10-6 g.L-1三聚氰胺的相对标准偏差为3.42%.与此同时,将所建立的方法用于奶粉中三聚氰胺的测定,结果令人满意.     

Molecularly imprinted polymer as SPE sorbent for selective extraction of melamine in dairy products

In this paper, a highly selective sample cleanup procedure combining molecular imprinting and solid-phase extraction (MI-SPE) was developed for the isolation of melamine in dairy products. The molecularly imprinted polymer (MIP) was prepared using melamine as the template molecule, methacrylic acid as the functional monomer and ethylene glycol dimethacrylate as the cross-linking monomer. The melamine imprinted polymer was used as selective sorbent for the solid-phase extraction of melamine from dairy products. An off-line MI-SPE method followed by high-performance liquid chromatography with diode-array detection for the detection of melamine was also established. The mean recoveries of melamine from ultra-heat treatment (UHT) milk and milk powders were 92.9-98.0% and 91.6-102.8%, respectively. Good linearity was obtained from 0.5 μM to 10 μM (r > 0.999) with a quantitation limit of 0.5 μmol/L (0.06 ppm) which was sufficient to analyse melamine at the maximum level permitted by U.S. Food and Drug Administration (1 ppm) in dairy products. It was demonstrated that the proposed MI-SPE-HPLC method could be applied to direct determination of melamine in dairy products.     

Synergistic flame retardant effect of melamine in ethylene–vinyl acetate/layered double hydroxides composites

Mg–Al–Fe ternary layered double hydroxides (LDHs) were synthesized based on Bayer red mud by a calcination–rehydration method, and characterized by X-ray diffraction (XRD) and thermogravimetric analysis (TG). The synergistic effects between melamine and LDHs in ethylene–vinyl acetate (EVA) composites were studied using limiting oxygen index (LOI), UL 94, cone calorimeter test (CCT), smoke density test (SDT), and thermogravimetry–fourier transform infrared spectrometry (TG–IR). Though melamine decreases the LOI values of EVA/LDHs/melamine composites, a suitable amount of melamine can apparently improve UL 94 rating; the composite with 45 % LDHs and 5 % melamine can pass UL 94 test. The CCTs results indicate that heat release rates (HRR) of EVA/LDHs/melamine composites decreased in comparison with that of EVA/LDHs composites. The SDT results show that melamine is helpful to smoke suppression. The TG–IR data show that the ternary composites have a higher thermal stability than that of the binary composites.     

磺化改性聚四氟乙烯纤维固相萃取-高效液相色谱联用测定奶制品中的三聚氰胺

采用新型固相萃取材料磺化的甲基丙烯酸缩水甘油酯接枝聚四氟乙烯（PTFE-g-GMA-SO3H）纤维填充微柱预富集和流动注射(FI)与高效液相色谱(HPLC)联用测定样品中痕量的三聚氰胺。 建立了以该纤维作为吸附剂在线测定奶制品中三聚氰胺的新方法。 对三聚氰胺的富集与洗脱条件进行了优化,并得出三聚氰胺的分析特性：该方法对三聚氰胺的检出限为1.13×10-2 mg/L,富集倍数为300,RSD为7.6%（n=9,三聚氰胺质量浓度为0.2 mg/L）。 该方法应用于2种奶制品中的痕量三聚氰胺的测定,样品加标回收率分别为98%和102.5%。