基于氧化石墨烯淬灭效应的DNA传感器特异性检测三聚氰胺

三聚氰胺(Melamine)在食品中的违规添加造成了严重的社会后果,引起了人们对三聚氰胺及其衍生物的普遍关注。本文利用氧化石墨烯(GO)独特的淬灭效应,以及GO与DNA和三聚氰胺相互作用的差异,建立了一种简便快速、特异性好的三聚氰胺检测方法。GO吸附荧光标记寡核苷酸(Fam-DNA)并导致荧光淬灭,得到低荧光的复合物,加入三聚氰胺后,GO与三聚氰胺的强相互作用导致DNA从GO表面脱落下来,荧光得到恢复。加入对照样品葡萄糖、麦芽糖、果糖等,荧光值没有明显升高。相比于以往检测三聚氰胺的方法,该方法操作简便、成本低廉、特异性好,适用于大量样品的快速初步筛选。     

蜜胺泡沫塑料在建筑中的应用

作为一种高开孔率的三维网丝结构的新型泡沫塑料,蜜胺泡沫塑料在阻燃、耐热稳定、隔热保温、吸音降噪等方面的优异性能,对于节能降耗、有效提升建筑环境舒适度和提高建筑自身安全水平方面具有重要的作用,作为一种新型多功能建筑材料,蜜胺泡沫塑料在建筑领域中具有广阔的应用前景。     

Morphology and thermo-mechanical properties of new hybrid coatings based on polyester/melamine resin and pyrogenic silica

Polyester/melamine (PM)-based formulations used in coil-coating applications were modified with pyrogenic silicas of different types. The influence of the chemical modification of the silica surface on various properties was investigated. The viscosity of filled PM formulations was measured. Transmission electron microscopy and dynamic mechanical measurements were used to characterize nanocomposite films. Roughness and gloss measurements were done on nanocomposite coatings. The results show that the viscosity and morphology observed are directly linked to the balance and nature of the interactions developed between the silica surface and the organic medium. Both hydrophilic and hydrophobic silica lead to too high viscosity of the filled formulation, to different silica dispersion and, as a consequence, to low gloss coatings. However with an adequate organo-modification of the silica, formulations compatible with the process and having a high gloss can be obtained. Additionally, the surface modification of silica has no obvious influence on the dynamic mechanical properties.     

低毒脲醛树脂胶的合成及胶液中游离甲醛的测定

探讨了改性剂对降低游离甲醛含量、改善胶粘剂性能的作用机理,研究了三聚氰胺、聚乙烯醇（PVA）改性脲醛树脂胶粘剂（UF胶）的制备工艺和配方,实验得出：采用弱碱-弱酸-弱碱的工艺,添加适量三聚氰胺和聚乙烯醇,反应最高温度控制在90℃,反应时间2~3 h,n（尿素）∶n（甲醛）=1∶1.4,尿素按7.0∶2.0∶1.0的质量比分3次投料,可制得低毒脲醛树脂胶粘剂。     

三聚氰胺反应器投料的优化操作

分析了三聚氰胺反应器的投料工况,总结归纳出3万t三聚氰胺反应器的投料条件和投料的最佳负荷为：反应器压力8．0MPa,投料负荷为27％,投料温度为400℃,加氨量为780～800kg/h。     

高效液相色谱法检测食品接触材料中三聚氰胺的残留量

建立了一种用液相色谱技术检测分析食品接触材料中三聚氰胺残留量的方法。样品采用0.1 mol/L盐酸作为提取溶液,70℃水浴超声提取。色谱分离采用NH2柱,流动相为V(乙腈):V(5mmol/L磷酸盐缓冲溶液,pH 6.5)=75:25,二极管阵列检测器检测。在优化条件下,三聚氰胺浓度在0.2-100 mg/L范围内与其峰面积线性关系良好,检出限(S/N=3)为0.02 mg/L。在100μg的添加水平下,三聚氰胺的回收率在80-99%之间,相对标准偏差(RSD)为2.80-4.32%。揭示了原料中三聚氰胺残留量与成型品的三聚氰胺迁移量的正相关关系。结果表明,该法简便、快速,可准确测定食品接触材料中三聚氰胺残留量。     

Effects of melamine on the Maillard reaction between lactose and phenylalanine

The effects of melamine on Maillard reaction were investigated in chemical model systems. The reaction products in the model systems with/without melamine were analysed by GC–MS and LC–MS/MS. Impact of melamine on Maillard browning in the above models was also examined by colourimetric methods. It was found that melamine can react directly with lactose and Strecker aldehydes formed in Maillard reactions to produce new adducts. In addition, the presence of melamine in chemical model systems also affects the formation of Maillard flavours and browning.     

国内外三聚氰胺生产技术的最新进展（上）

综述了国内外三聚氰胺生产技术的新进展,着重介绍高压法的工和近几年来专利简介。     

蜜胺泡沫塑料性能与应用

蜜胺泡沫塑料是以蜜胺为主要原料生产的柔性泡沫塑料,不但具有一般泡沫塑料的性能,还具有优异的阻燃、无毒卫生、吸声、隔热等性能。作为一种新型材料,在许多领域具有非常广泛的市场前景。     

蜜胺浆液吸收低浓度SO_2动力学研究

本文采用双全混搅拌反应器,对蜜胺浆液吸收低浓度SO_2气体这一气、液、固三相反应过程的规律进行了研究。通过理论分析和实验考察,证明在该三相反应过程中,SO_2与蜜胺的化学反应是在极其靠近气液界面的液膜内进行的瞬时反应;SO_2在气相中的传质为三相反应过程的速率控制步骤。该三相反应过程的动力学模型可简化为: N_A=k_(Ag)p_A 并且用实验证明了该模型的正确性。通过对实验数据回归,得到了双全混搅拌反应器中气相传质系数的关联式: k_(Ag)=1.2706×10~(=5)+8.1108×10~(=9)Re