活性/可控自由基聚合制备分子印迹纳米膜

通过可逆加成-断裂链转移(RAFT)自由基反应,在球形硅胶表面制备了分子印迹纳米膜.茶碱吸附实验显示,与对照组的杂化球形硅胶相比,分子印迹纳米膜杂化球形硅胶对茶碱具有更高的吸附结合能力.利用RAFT所具有的活性/可控的特点,通过改变实验条件控制分子印迹纳米膜在硅胶表面的生长,可以得到较厚的分子印迹纳米膜以获得较好的吸附量,也可以得到较薄的分子印迹纳米膜以获得较好的吸附效率.     

RAFT法在纳米SiO_2表面接枝PBA及其对POM的改性研究

采用可逆加成-断裂链转移(RAFT)聚合法在纳米二氧化硅(SiO2)表面接枝聚丙烯酸丁酯(PBA),并采用透射电镜(TEM)、广角X射线衍射(WAXD)、差示扫描量热仪(DSC)及热重分析仪(TGA)等手段研究纳米SiO2及SiO2-PBA复合粒子的添加对聚甲醛(POM)结晶性能及热稳定性的影响.结果表明:用RAFT聚合方法有少量的PBA接枝于纳米SiO2表面;纳米SiO2及SiO2-PBA复合粒子的添加不改变聚甲醛的晶型;粒子的添加使用POM结晶温度、熔点和结晶度升高;且粒子的添加均使POM热稳定性提高.     

HPAR／HDIT聚氨酯材料的热降解动力学

用热重-红外联用和动态力学热分析法研究了羟基丙烯酸树脂与六亚甲基二异氰酸酯三聚体反应生成的聚氨酯材料(PU)在254 nm紫外线(UV)照射加速老化前后的热降解动力学,结果表明在N2氛中硬链段热降解成含—NCO的化合物,而软链段热降解成含—COOR或—CO—的化合物,热降解是一级反应.在4个不同温度阶段,热降解反应的活化能(E)和频率因子随温度的变化而变化.UV照射前,PU硬链段的E在40.4~43.7 k J/mol,软链段的E在144.5~163.4 k J/mol,硬链段的热稳定性比软链段差.经UV照射8 500 h后,硬链段的E在43.3~50.6 k J/mol,软链段的E在136.5~157.2 k J/mol,PU的最大热降解速率温度降低了2~7 K.UV照射虽劣化了软链段的热稳定性,但也使PU进一步发生聚合,玻璃化转变温度有所提高.     

Photodegradation of N-nitrosodiethylamine in water with UV irradiation

The direct photolysis of N-nitrosodiethylamine(NDEA) in water with ultraviolet(UV) irradiation was investigated.Results showed that NDEA could be completely degraded under the direct UV irradiation.The effects of the experimental conditions,including the initial concentration of NDEA,humic acid and solution pH,were studied.The degradation products of NDEA were identified and quantified with gas chromatography-mass spectrometry(GC-MS) and high performance liquid chromatography(HPLC).It was confirmed that methylamine(MA),dimethylamine(DMA),ethylamine(EA),diethylamine(DEA),NO2-and NO3-were the main degradation products.The photolysis degradation mechanism of NDEA was also discussed.As a result of N-N bond fission,NDEA was degraded by direct UV irradiation.     

Styrene polymerization catalyzed by nickel complexes bearing hydroxyindanone-iminate ligands

Activated by methylaluminoxane, mononuclear bis（hydroxyindanone-iminate）nickel complexes Ni[ArN=CC2H3（CH3）C6H2（R）O]2 （Ar = 2,6-i-Pr2C6H3, R=Me（1）, R=CI（2）, and R=H（3）） showed good activity for the styrene polymerization. The effect of many reaction parameters including the AI/Ni ratio, temperature, and reaction time on catalytic activities of catalytic systems and the molecular weights of the obrained polystyrene was ascertained. The highest activity of 1.34×10^5g（PS）·mol^-1（Ni）·h^-1 was obtained under the optimum reaction condition. The ^13C NMR spectra of the polymers revealed that the polymer was isotactic-rich atactic polystyrene. And the coordination mechanism was confirmed by the analyses of the polymer chain end-groups.     

激光辐照加工的硅氧化结构的受激发光(英文)

我们用1064nm脉冲激光在硅表面加工出小孔结构,再作高温退火处理形成硅氧化纳米结构,发现该结构在692和694nm波长处有很强的光致受激发光(PL).通过进一步实验发现:该PL发光有明显的阈值表现和光泵线性增强效应,证明该PL发光确实是光致受激辐射.我们提出氧化界面态模型来解释光致受激发光机理,在氧化界面态与价带顶空穴态之间形成粒子数反转.这项工作为硅基上发光器件的光电子集成研发开辟了新的途经.     

无甲醛防皱整理剂MA-AA-IA共聚物的合成和性能研究

以顺丁烯二酸酐(MA)、丙烯酸(AA)和衣糠酸(IA)为主要单体进行水溶液聚合,通过采用过氧化顺丁烯二酸引发体系制备了羧基封端的三元共聚物,测定了其作为纺织品无甲醛防皱整理剂的性能,探讨了端基对聚合物应用性能的影响,确定了AA与MA的最佳合成条件:AA与MA的质量比为2.5∶1,MA-AA与IA为9∶1,聚合温度80～90℃,双氧水用量为单体的30%;在优化的应用条件下,该三元共聚物的防皱整理性能与丁烷四羧酸(BTCA)相当.     

国审小麦新品种“富麦2008”的选育研究

利用"豫麦57"为基础材料,通过辐射诱变与太空诱变选育出具有高产、稳产、优质、抗逆和广适性小麦新品种"富麦2008".该品种与原始亲本"豫麦57"相比,克服了原品种黑胚率高、落黄差的严重缺陷,同时,保留了原品种的高产特性.     

Reverse atom transfer radical polymerization of styrene in emulsion initiated by AIBN or V50

Reverse atom transfer radical polymerization of styrene was conducted in emulsion by using Cu（Ⅱ）/2,2＇bipydine or Cu（Ⅱ）/phen complexes, AIBN or V50 as the initiator, Brij-98 or OP-10 as the surfactant. The results of GPC showed that both polymerization processes exhibit living characters when using AIBN as the initiator. However, when V50 was used, the monomer conversion was fairly low and the whole polymerization was not controlled well. The measurement of particle size and its distribution told us that the latex particles were mean and stable when using Brij-98 as the surfactant.     

混合钌配合物[Ru(bpy)_n(Hdpa)_(3-n)]~(2+)中中心离子与配体之间的相互作用

通过微波加热方式,快速地合成了钌与联吡啶和二吡啶胺所形成的系列配合物,［Ｒｕ（ｂｐｙ）ｎ（Ｈｄｐａ）３－ｎ］２＋（ｎ＝０,１,２,３）．测定并归属了各种配合物的１３Ｃ－ＮＭＲ谱．通过比较各配合物及自由配体的化学位移,得出Ｒｕ（Ⅱ）对Ｈｄｐａ的ｄ－π反馈作用大于其对ｂｐｙ的ｄ－π反馈作用;混合配合物中不同配体之间的屏蔽作用大于单一配合物中同种配体之间的相互屏蔽作用．