不同边界条件下球形颗粒吸附剂内扩散方程的分析解和数值解的比较

吸附质在球形颗粒的内扩散可用固相内扩散偏微分方程描述，当使用吸附剂球心的浓度为零时，可得到解析解模型；当使用在球心的浓度梯度为零时，只能得到数值解。本文分析了在这两种不同的边界条件下导出的分析解和数值解模型之间的差别，当分别用两种模型计算颗粒内瞬时溶质浓度分布和吸附剂颗粒体积平均吸附量的结果表明：在吸附发生的初期（如τ＝０．０００１），二者的相对误差为２４％，当吸附持续较长时间时，二者的数值基本相     

两种由萘二酰亚胺衍生物构建的配位聚合物的合成、结构和光致变色性能

具有可逆颜色变化和适当变色寿命的光致变色材料对于无墨水和可擦除打印技术十分重要。我们将1，4，5，8-萘四羧酸二酐与甲硫氨酸结合，设计了一种基于 1，4，5，8-萘二酰胺(NDI)的桥联有机配体(H₂ncm)，并以 Zn²⁺和 H₂ncm为原料，通过溶剂热反应合成了2种配位聚合物。化合物[Zn(ncm)(H₂O)₄]·2DMF (1)包含1个Zn²⁺、1个ncm^2-配体、4个配位水分子和2个DMF分子。Zn²⁺处于八面体的配位环境中，并通过 ncm^2-配体连接形成链状结构。化合物[Zn₂(ncm)₂(H₂O)₄] (2)包含 2个 Zn²⁺、2个 ncm^2-配体和4个配位水分子。2个Zn²⁺原子通过2个羧基桥联形成双核结构，并进一步通过ncm^2-配体连接形成二维层结构。2显示出从黄色到深棕色的光致变色现象。这种光诱导产生的颜色可以稳定至少3周，但在70 ℃加热时在5 min内即可恢复本来的颜色。我们证明了这种光致变色是源于光照射下NDI·自由基的产生。     

A REVIEW OF OXYGEN-CONTAINING SURFACE GROUPS AND SURFACE MODIFICATION OF ACTIVATED CARBON

1. INTRODUCTION Activated carbons (ACs) have been widely used as adsorbents in environmental protection, e.g. removing organic or inorganic pollutants from liquid effluents and voltaic organic compounds (VOCs) from polluted air. It has been well known that the adsorptive capacity of ACs is not only determined by its textural properties (e.g. specific surface area, pore size distribution, pore volume), but also related to its surface chemistry. Many studies have demonstrated that the ad…     

EXPERIMENTAL STUDY ON THE UNIFORMITY OF LARGE AREA INTENSE RELATIVISTIC ELECTRON BEAMS

The uniformity of intense relativistic electron beams under a converging magnetic guide field is studied experimentally in this paper. In the experiments, fluence calorimeter and X-ray pinhole photograph were used to measure the beam uniformity. The experimental results show that the externally applied magnetic flux density at the cathode and the shape of cathode face have considerable influence on the beam uniformity, The beam uniformity better than 80% is obtained over an area of 200cm² when the externally applied magnetic flux density at the cathode is about 0.6T and the cathode face is concave to a depth of 1.5 mm, relative to the cathode edge.     

猪脊髓中两个生物活性肽的分离与部份鉴定

从猪脊髓中分离了两个生物活性肽,并进行了部分鉴定.氨基酸分析、电泳、等电聚焦及N末端残基丹磺酰衍生物层析分析表明,这两个肽都是纯肽.氨基酸组成分析及Sephadex G50(超细)薄层层析测定的表观分子量表明SCP-1是个31肽,SCP-2是个25肽.SCP-1及SCP-2的N末端氨基酸分别为精氨酸及色氨酸。SCP-1刺激离体豚鼠迥肠收缩,SCP-2引起大鼠血压降低,两者均无吗啡样活性。SCP-I及SCP-2的化学组成和生物学性质与迄今发现的所有已知肽不同。     

用小波和分维数方法处理喘振实验数据

本文针对离心压缩机喘振的实验数据，采用小波分析，发现喘振先兆的频率与后来发生的喘振频率接近，且喘振先兆和喘振均为周期性的脉动．用分维数方法进行处理分析，通过计算压缩机系统不同工况下的关联维数，可以看出关联维数是信号复杂程度的度量．以上工作为实施喘振的主动控制提供了依据．     

Nonadiabatic Geometric Quantum Computation with Asymmetric Superconducting Quantum Interference Device

We propose a method of controlling the dc-SQUID (superconducting quantum interference device) systemby changing the gate voltages, which controls the amplitude of the fictitious magnetic fields Bz, and the externallyapplied current that produces the piercing magnetic fiux φx for the dc-SQUID system. We have also introduced aphysical model for the dc-SQUID system. Using this physical model, one can obtain the non-adiabatic geometric phasegate for the single qubit and the non-adiabatic conditional geometric phase gate (controlled NOT gate) for the twoqubits. It is shown that when the gate voltage and the externally applied current of the dc-SQUID system satisfies anappropriate constraint condition, the charge state evolution can be controlled exactly on a dynamic phase free path. Thenon-adiabatic evolution of the charge states is given as well.     

用电光相位调制器显示超声行波波前

本文提出了一种用连续激光器,在时间相关理论依据下,以电光相位调制显示超声行波波前的新方法;并考虑到运动相位和静止相位的差异,提出了一种特殊的空间滤波技术,从而显示了超声行波的高对比像.     

无水NdCl3和无水PrCl3单晶体中Nd3+的吸收光谱及其量子态

在光谱的可见和近红外区域内系统地研究了无水NdCl₃和无水PrCl₃(含0.1％NdCl₃)单晶体中Nd³⁺的吸收光谱。其吸收光谱线群的结构与含2％NdCl₃的无水LaCl₃单晶体中的Nd³⁺的吸收光谱一样,只是所有相应的吸收光谱线群有一个向光谱长波端的整体移位。相应上子能级间的移位(相对于基态)与单晶体原胞长度c₀成正比(见图3)。 关键词：