决定论性逐步加速交通流模型的渐近稳态行为

研究Nagel-Schreckenberg(NS)交通流元胞自动机模型在不考虑车辆随机延迟情况下的决定论性模型的基本图,即渐近稳态的车流平均速度作为车辆密度的函数关系．证明决定论性NS模型,在车流的自组织作用下,其渐近稳态的基本图,与决定论性Fukui-Ishibashi(FI)交通流模型的基本图完全相同．这个结果表明,若把FI交通流模型中的车辆突然加速方式（即车辆速度可以在仅仅一个时步内加速到其最高速限M或前方空距所允许的最大速度）,改变为车辆逐步加速方式（车辆速度在每一时步中最多仅能增加一个速度单位）,则车辆的自组织相互作用,并不会改变其车流的长时间渐近稳态行为． 关键词：     

有机/无机薄膜凝胶动态过程的实时光学二次谐波产生研究

采用实时光学二次谐波产生(SHG)测量方法,以两亲性分子半花菁为掺杂探针分子,对溶胶-凝胶技术制备的玻璃薄膜的凝胶干燥的动态过程进行了研究.结合紫外—可见吸收光谱的测量,发现：因两亲性分子在膜中的自取向性可诱导出二阶光学非线性,溶胶-凝胶技术制备的有机/无机复合膜的凝胶干燥过程可通过薄膜SHG强度的变化半定量地反映.凝胶干燥收缩导致有序掺杂分子数减少,膜片的光学非线性减弱.该过程随薄膜处理温度的升高而急剧缩短;另外,有机分子在膜中的聚集程度随膜片处理温度的增加而很快减少. 关键词：     

Si基GaN外延层光致发光光谱与二次离子质谱的研究

报道了在Si基上用简便的真空反应法制备出GaN外延层．光致发光光谱测试结果表明不同的生长温度和退火工艺会对GaN外延层的发光特性产生影响,在1050℃下生长的GaN外延层的发光强度高于其他温度下生长的发光强度,退火可以使GaN外延层的发光强度增强．二次离子质谱(SIMS)测试结果表明外延层中Ga和N分布均匀,在表面处Ga发生了偏聚,同时外延层中还存在Si,O等杂质,这使得外延层中背景电子浓度高达1.7×10¹⁸/cm³. SIMS测试结果还表明,在外延生长前采用 关键词：     

硅胶基质弱阳离子交换剂的合成及蛋清中溶菌酶的分离

用间接法合成了硅胶基质弱阳离子交换剂（ＸＩＤＡＣＥ－ＷＣＸ）,详细研究了合成填料的色谱性能,并与商品柱（Ｓｈｉｍ－Ｐａｃｋ ＷＣＸ－１和Ｐｏｌｙ ＣＡＴＡ）进行了比较。结果表明：合成柱比商品柱具有较高的分辨能力。通过考察合成填料的疏水性、蛋白质的保留值与等电点（ｐＩ）的关系、流动相的ｐＨ值和盐浓度对蛋白质保留行为的影响,论证了合成填料的离子交换特征。利用合成的色谱填料从蛋清中分离出纯度较高的溶菌酶     

自粘结低硅铝X型沸石的结构、吸附和N2/O2分离比

用原位合成方法直接将高岭土转化为所需形状的低硅Ｘ型沸石（ＰＬＳＸ）,经Ｘ衍射,＾２９Ｓｉ＾２７ＡｌＭＡＳＮＭＲ谱证实ＰＬＳＸ的结构硅铝比接近１,它含ＬＳＸ的组成为４０．４０％,含４Ａ的组成为１７．９２％,其余为无定形硅、铝氧化物、ＬＳＸ的骨架硅铝比接近１,是骨架负电荷分离最是均匀的Ｘ型沸石,２９３Ｋ时静态法测定和推算ＬＳＸ的饱和吸附水达３９．８０ｗｔ％,ＬＳＸ的组成为Ｎａ９６－ｘＫｘ（Ａｌ９６Ｓｉ     

Balance Equation Approach to Nonlinear Polaronic Transport

Balance equations beyond the lowest order perturbation expansion for high-field electronic transport are developed and used to discuss the polaronic resistivity in polar semiconductors and other systems. Significant corrections in the case of high electric field are expected.     

Reductive Desulfurization of Thioamides to Amines by Catalytic Hydrogen Transfer Reaction

Introduction Reductive desulfurization of thioamides to amines is one of the methods to prepare amines and is generally achieved by a) Zn in acid, b) sodium or aluminum amal- gams, c) lithium alumminium hydride, d) Raney Ni and e) electrolytic reduction. These methods are not very convenient to be operated and some need more complex instrument. Here is reported the reductive desulfurization of thioamides to amines by catalytic hydrogen transfer reaction(CHT).     

Electric Field Effect on the Fractional Quantum Hall Conductivity

We have studied the effect of an external electric field on the dc fractional quantum Hall conductivity of a two-dimensional system with the dynamic structure function in the single-mode approximation. In analogy with the integral quantum Hall effect and euperconductivity, a gap-dependent critical electric current J_c, also exists in the case of fracctional quantum Hall conduction, above which is the maximum current for system to maintain superfluidity. We also find that, depending on the gap width and the phonon velocity, phonon may or may not contribute to the conductivity even at a finite lattice temperature, in agreement with experiments.     

Hot-Electron Transport and Coupled-Mode Optic Phonon in a Polar Semiconductor

The effect of coupled-mode-LO phonons on the electronic transport in a polar semiconductor is studied within a model which takes the internal thermalization time of the LO phonon system and the relaxation time of the whole lattice as parameters. Our analysis shows that although the hot-electron energy-loss to LO phonons is drastically enhanced and the LO-phonon-induced linear mobility is markedly reduced by the formation of coupled modes at low temperatures, in a realistic polar semiconductor when all the scattering mechanisms included, the coupled-mode effect on the transport properties is almost buried.     

过硫酸盐紫外氧化-非分散红外吸收法测定水中痕量总有机碳

采用Ｐｈｏｅｎｉｘ８０００总有机碳分析仪,以ＵＶ－Ｎａ２Ｓ２Ｏ８－ＮＤＩＲ氧化波了水中痕量机碳（ＴＯＣ）。讨论了酸度、氧化剂浓度、有机物氧化效果、无机碳对测定结果的影响等。方法检出限为０．００２４ｍｇ／Ｌ,回收率为９４．０％￣１１２％,精密度０．８￣５．３％。该法已应用于湖水、河水、自来水、地下水、泉水等自然水体及纯净水、蒸馏水、反渗透（ＲＯ）净化水特瓣总有机碳含量的测定。