甲烷-空气-H2O模拟光化学反应体系中CH3OO

在1.013×105 Pa,(298±2)K及O2-N2气氛下,研究了羟基自由基*OH引发的甲烷光化学反应体系中过氧甲基自由基CH3OO*自身复合反应.反应物和产物采用长光路Fourier红外光谱(LP-FTIR)和高效液相色谱(HPLC)测定.证实产物中有甲基过氧化氢(CH3OOH,MHP)和过氧甲醚(CH3OOCH3,DMP)存在并首次在该体系中发现了羟甲基过氧化氢(HOCH2OOH,HMHP).HMHP的检出表明,CH3OO*自身复合的可能途径之一生成了Criegee中间体过氧次甲基双自由基*CH2OO*.采用G2,G2(MP2)和G2(ful)方法对一些反应的标准焓变和标准Gibbs自由能变化进行了理论计算.结果表明CH3OO*自身复合生成*CH2OO*及*CH2OO*与H2O反应生成HMHP的途径在热力学上是可能的.     

丙烯酰胺共聚合及产物分散性的研究

采用水溶性引发体系研究了丙烯酰胺的均聚以及与几种乙烯基单体的共聚反应。探讨了引发剂、温度、单体浓度及加热时间对所得聚合物相对分子质量及其分散性能的影响。对产物的结构特性和相对分子质量分布进行了表征,并考察了共聚物的分散性能。丙烯酰胺共聚物同均聚物相比,分散性能有明显的改善。     

侧基发光性单体与无机纳米颗粒的组装及其光学性质

发光二极管可广泛应用于计算机、电视以及公共场所大型平板显示器等领域 .其所用的发光材料包括无机材料、有机小分子材料和高分子材料等几类 .作为发光材料要具有高的发光效率,良好的稳定性,以及为了实现全色显示其发光波长要能调节 .发光波长的调节,一般是通过能带的变化来实现 .通常使能带变化的方法有掺杂、改变共轭长度（有机材料） [1－ 4]、和改变颗粒大小（半导体纳米材料） [5, 6]等 .我们在进行无机半导体纳米材料与有机分子材料的组装复合时发现有机发光分子在无机颗粒表面的有序排列也能使发光波长显著变化,这可望成为调…     

乙烯基单体-N-取代马来酰亚胺共聚物玻璃化温度研究

用差示扫描量热仪对乙烯基单体/N-取代马来酰亚胺共聚物的玻璃化温度(T_g)进行测定.研究了共聚物组成、序列结构、乙烯基单体和N-取代马来酰亚胺种类对共聚物T_g的影响.提出了含共聚物组成和序列结构的T_g预测方程,该方程不仅适合于无规共聚物,还适合于具有严重交替倾向的共聚物.     

弱可约极大三角代数的上同调

In this paper, we introduce the concept of weakly reducible maximal triangular algebras φwhich form a large class of maximal triangular algebras. Let B be a weakly closed algebra containing 5φ, we prove that the cohomology spaces H^n(φ, B) (n≥1) are trivial.     

Carrier--envelope phase effects for a dipolar molecule interacting with ultrashort laser pulse

In this paper the phase-dependent features of ultrashort laser pulse resonant propagation in a two-level dipolar molecule are demonstrated by solving full Maxwell--Bloch equations. The electronic properties of dipolar molecule 4-trans-[p-(N, N-Di-n-butylamino)-p -stilbenylvinyl] pyridine (DBASVP) molecule, one-dimensional asymmetric organic molecule, is calculated by density functional theory at \textit{ab initio} level. The numerical results show that the carrier propagation and the spectrum evolution of the pulse are sensitive to its initial phase and the phase sensitivity is more obvious for larger area pulse. The phase-dependent feature is more evident in dipolar molecule because the permanent dipole moment makes the nonlinear effects stronger.     

Solitary Excitations of Dipolar Bosons in Optical Lattice under Magnetic Fields

We obtain the multisolitary solutions of the extended Bose-Hubbard model which describes dipolar Bose- Einstein condensates in optical lattices under time-dependent magnetic fields, and indicate that the nonlinearity is due to both on-site short-range interactions and also （long-range） dipole-dipole interactions which can act between neighboring sites. The discrete breathers as nonlinear excitations are always oscillatory in time and can also be spatially localized, while the oscillatory frequencies are determined by an external field. We show that these excitations will be observable and discuss how the parameters can be tuned in future experiments.     

含三苯基乙基苯氧基聚氧乙烯醚甲基丙烯酸酯功能单体的缔合型乳液增稠剂的制备及增稠机理

采用半连续法乳液聚合以甲基丙烯酸、丙烯酸乙酯、邻苯二甲酸二烯丙酯和不同量的功能单体三苯基乙基苯氧基聚氧乙烯醚甲基丙烯酸酯(SEM-25)为原料合成了疏水改性碱溶性增稠剂乳液. 测定了增稠剂乳液的粘度、透光率、pH、粒径及其分布, 结果表明随着pH值的增加, 乳液的粘度和透光率首先迅速升高, 然后缓慢下降. 随着SEM-25用量的增加, 乳胶粒的粒径先增大后减小. 与不含SEM-25的乳液增稠剂相比较, SEM-25低含量增稠剂的增稠效果和抗剪切性没有提高, 只有当SEM-25用量提高至单体质量的12%, 且乳液固含量大于0.65%时, 所制备缔合型增稠剂乳液的粘度和流变性比不含SEM-25的增稠剂才有明显提高. 在此基础上研究了增稠剂对苯丙乳液的增稠性. 含有增稠剂的苯丙乳液的粘度和透光率随pH值的变化与纯增稠剂乳液的变化类似. 只有当加入0.34 wt%苯丙乳液固体质量的增稠剂, 并且增稠剂中SEM-25含量达到5 wt%时苯丙乳液的粘度与使用不含SEM-25的增稠剂增稠的粘度相比才有明显增高. 在此基础上对增稠剂的增稠机理进行了探讨.     

甲基丙烯酸羟乙酯的乳液聚合

甲基丙烯酸羟乙酯;乳液聚合;单体转化率;凝聚率;粒径     

Hydrothermal Syntheses and Characterizations of Two One-dimensional Molybdenum 1,4-Butylenediphosphonates

1 INTRODUCTION Interest in metal phosphonate chemistry has in- creased in recent years, not only because of their rich structural chemistry[1～3] but also owing to their potential applications in catalysis, absorption and intercalation reaction[4～6]. The introduction of a se- cond metal-ligand component as a charge-compen- sating unit and structure-directing component into polyoxomolybdenum/oxovanadium organodi-phos- phonates has provided us a powerful method to syn- thesize this family o…