Navier-Stokes方程带Backtracking技巧的两重网格算法

1 引 言考虑二维不可压 Navier-Stokes方程:     

Melt rheology of polylactide/montmorillonite nanocomposites

In this article, the linear and nonlinear shear rheological behaviors of polylactide (PLA)/clay (organophilic‐montmorillonite) nanocomposites (PLACNs) were investigated by an Advanced Rheology Expanded System rheometer. The nanocomposites were prepared by master batch method using a twin‐screw extruder with poly(ε‐caprolactone) (PCL) as a compatibilizer. The presence of org‐MMT leads to obvious pseudo‐solid‐like behaviors of nanocomposite melts. The behaviors caused by the formation of a “percolating network” derived from the reciprocity among the strong related sheet particles. Therefore, the storage moduli, loss moduli, and dynamic viscosities of PLACNs show a monotonic increase with MMT content. Nonterminal behaviors exists in PLACNs nanocomposites. Besides the PLACNs melts show a greater shear thinning tendency than pure PLA melt because of the preferential orientation of the MMT layers. Therefore, PLACNs have higher moduli but better processibility compared with pure PLA. © 2007 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 45: 3189–3196, 2007     

Crystallographic report: Crystal structure of tetra(4‐methyl‐5‐imidazole‐carboxyaldehyde)zinc(II) diperchlorate

The central zinc(II) atom in the title complex is tetrahedrally coordinated by four nitrogen atoms derived from 4‐methyl‐5‐imidazolecarboxyaldehyde ligands with Zn? N in the range 2.007(3) to 2.026(4) Å. Copyright © 2003 John Wiley & Sons, Ltd.     

New Interfaces for Coupling TLC with TOF SIMS

JPC – Journal of Planar Chromatography – Modern TLC - Two interfaces have been tested for coupling thin-layer chromatography (TLC) with time-of-flight secondary-ion mass spectrometry...     

The Gain Properties of 1-D Active Photonic Crystal

The terminology ‘ID frequency’(w ID) is proposed after analyzing the 1D active photonic crystal based on the transfer matrix method. The relationship between wID and the structure parameters of the photonic crystal is investigated.     

Probing proton halo of the exotic nucleus28S by elastic electron scattering

Elastic electron scattering on the exotic light nucleus²⁸S is investigated in the plane wave Born approximation. The variation of the squared form factors of²⁸S with momentum transfer is compared with that of³²S. It is found that the behavior of the form factors near the second minimum (with a moderate momentum transfer) is sensitive to the alteration of the charge density distribution of halo protons in²⁸S. This indicates that elastic electron scattering can be a good probe of the structure of proton-halo nuclei.     

CT实验仪的研制及其在物理教学中的应用

介绍了我们研制的CT实验仪的原理及开发，使用情况，包括CT的物理，数学原理，CT装置的结构，性能、工作原理等，文末给出实验结果，并对装置在物理实验教学中的意义作了讨论。     

大米中硒的FI-HG-AAS测定方法研究

研究了原子化器温度、载气流速、KBH4 浓度等条件对流动注射 氢化物发生 原子吸收光谱法 (FI-HG -AAS)测定硒时的影响。建立了FI-HG -AAS测定大米中硒的分析方法。在优化的工作条件下 ,测定硒的最低检测浓度为 0 3 3 μg·L- 1,线性范围为 0～ 5 0 μg·L- 1,相对标准偏差小于 4% ,加标回收率为 94%～ 1 0 2 %。本法克服了传统的间断氢化物发生 原子吸收光谱法分析速度慢、样品耗量大、操作繁琐且因手工进样在进样速度和进样体积上容易带来误差等缺点。方法操作简便、快速 ,灵敏度及自动化程度高 ,已广泛应用于大米及富硒大米中微量硒的测定     

聚合物分散液晶光栅的衍射特性的研究

报道了一种由聚合物分散液晶膜与具有周期性条状电极结构板结合的新型光栅器件，借助于聚合物分散液晶膜的电光特性，这种栅对入射光的散射或衍射取决于对其施加的电压，即它是电场可调的，实验结果显示出当驱动电压超过器件器件阈值电压时，衍射光的强度和衍射斑的可见级次被电场调制，而且它能入射光的线性偏振态变为椭圆偏振态。     

注入控制铜蒸气激光方向性时间过程测量

实验研究了注入控制对铜蒸气激光非稳腔输出光束质量的影响，从输出光发散角时间分辨过程的测量结果说明注入加速被注入腔内激光发散角的减小过程。由于被注入腔内放大自发辐射的存在，为得到较好的注入控制效果，注入光的脉宽和进入被注入腔的延时必须恰当。