Temperature effects on surface activity and application in oxidation of toluene derivatives of CTAB-SDS with KMnO4

The γ_cmc values of CTAB-SDS decrease from 63.67 mN/m at 10‡C to 36.38 mN/m at 90‡C, slightly lower than those of either CTAB or SDS. Correspondingly, the CMC of CTAB-SDS decreases almost by half. The increase of surface activity of CTAB-SDS can be attributed to the relatively weak electrostatic interaction at high temperature, which is supported by the increase of solubility of CTAB-SDS with rise in temperature. Catalytic effect on oxidation of toluene derivatives with potassium permanganate follows the order CTAB-SDS > SDS > CTAB. This is not caused by the dissociative effect of CTAB-SDS with low surface activity at low temperature, as seen from the fact that almost all oxidative products can be retrieved for different toluene derivatives and surfactants by mimicking the conditions of reaction. In the emulsifications of toluene derivatives at 90‡C, the time that turbid water layers of surfactant solutions take to become clear is the same as that of the catalytic effect on oxidation of toluene derivatives. Thus, it can be inferred that surfactants can improve the oxidation yields of toluene derivatives by increasing the contact between two reacting phases.     

HIRFL–CSR加速器中束流与真空中剩余气体的碰撞损失

研究了重离子加速器中束流与真空中剩余气体的碰撞损失过程和碰撞截面,在依据大量实验数据的基础上,提出了一组计算离子一原子的电荷交换截面的经验公式.以兰州重离子加速器HDRFL及冷却储存环CSR为例,给出了依据碰撞截面的公式计算束流在加速器真空中的传输效率的方法,并计算了在不同真空度下HIRFL的ECR源轴向注入束运线、注入器SFC、前束运线、主加速器SSC和后束运线等不同加速阶段及CSR的传输效率,并提出合理的真空度要求.HIRFL的真空分布测量和束流的损失测量证明了该计算方法的可靠性.     

Solitary waves and their bifurcations of KdV like equation with higher order nonlinearity

We investigate the KdV like equation with higher order nonlinearity ut + a(1 +bun)unux + uxxx = 0with n ≥ 1, a, b ∈ R and α≠ 0. The bifurcations and explicit expressions of solitary wave solutions for theequation are discussed by using the bifurcation method and qualitative theory of dynamical systems. Thebifurcation diagrams, existence and number of the solitary waves are given.     

Syntheses, structures, and properties of novel molybdenum and tungsten complexes of fullerenes

The synthesis and characterization of several fullerene-based organometallic complexes containing Mo and W is reported.     

Effect of ion impinging on the microstructure and field emission of carbon nanotubes

Effects of ion impinging on the microstructure and field electron emission properties of screen-printed carbon nanotube films were investigated. We observed that the plasma treatment modified the microstructure of CNTs along with the remarkable increase of emission site density. With the prolongation of ion impinging time, the emission current falls down first, and then rises up to higher than that of the untreated films. It is proposed that the change of emission characteristics is due to the different emission mechanisms. After the treatment, electrons are emitted predominantly from the nano-nodes on the tube wall instead from the nanotube tips.     

Multilinear interpolation between adjoint operators

Multilinear interpolation is a powerful tool used in obtaining strong-type boundedness for a variety of operators assuming only a finite set of restricted weak-type estimates. A typical situation occurs when one knows that a multilinear operator satisfies a weak L^q estimate for a single index q (which may be less than one) and that all the adjoints of the multilinear operator are of similar nature, and thus they also satisfy the same weak L^q estimate. Under this assumption, in this note we give a general multilinear interpolation theorem which allows one to obtain strong-type boundedness for the operator (and all of its adjoints) for a large set of exponents. The key point in the applications we discuss is that the interpolation theorem can handle the case q?1. When q>1, weak L^q has a predual, and such strong-type boundedness can be easily obtained by duality and multilinear interpolation (cf. Interpolation Spaces, An Introduction, Springer, New York, 1976; Math. Ann. 319 (2001) 151; in: Function Spaces and Applications (Lund, 1986), Lecture Notes in Mathematics, Vol. 1302, Springer, Berlin, New York, 1988; J. Amer. Math. Soc. 15 (2002) 469; Proc. Amer. Math. Soc. 21 (1969) 441).     

基于MMD算法的HMM参数重估计的矩阵表示

本文提出的MMD算法用于提高模型区别错误信息和正确信息的能力．利用该算法在对模型的参数进行重估计时．涉及到复杂的目标函数的梯度运算．击运用矩阵运算使得梯度运算变得简单明了，因此本文给出了MMD算法下的HMM参数重估计的矩阵表示形式并给出了证明．     

含氟碳菁染料聚集行为的研究

本文对五种不同结构的含氟碳菁染料的甲醇溶液及吸附在碘溴化银T 颗粒表面的聚集行为进行了研究 ,测定了照相性能 ,计算了增感倍率。Dye1 ,Dye2 ,Dye3在甲醇溶液中测得的单分子态吸收曲线 ,当取代基从C2 H5→CH3→无取代基时 ,最大吸收峰对应的波长向短波方向移动 ;乙基取代基的增感染料 (Dye1 )吸附在碘溴化银表面形成的J 聚集态峰值较高 ,对应的增感倍率也高。没有取代基的增感染料 (Dye3)不形成J 聚集 ,增感倍率低 ,有减感作用。Dye4与Dye5相比 ,Dye4具有尖而窄的J 聚集反射光谱 ,增感倍率高。结果表明 :不同结构的增感染料吸附在卤化银颗粒上形成的J 聚集态不同 ,吸收谱带窄的J 聚集态增感染料具有较高的增感倍率。     

新型菲涅尔线聚光太阳电池组件特性分析

以PMMA为材料,采用热压成型工艺加工线聚焦菲涅尔聚光棱镜,对在其聚光条件下不同入射角度情况下太阳电池的电流电压特性进行测试,结果表明:该菲涅尔线聚焦棱镜能有效提高太阳电池的单位输出功率,而且具有比较宽泛的集光角的特性,基本满足实际应用的要求.