Lattice Boltzmann Simulation of Sedimentation of a Single Charged Elastic Dumbbell in a Newtonian Fluid

Based on the lattice Boltzmann method, the sedimentations of elastic dumbbells with different charges in a Newtonian fluid under the same and different initial conditions are simulated. Due to the polarizing effects, there are Coulomb forces exerted on the charged elastic dumbbells during their sedimentations, which change their original motions significantly. All of the numerical results show that, if the charged elastic dumbbells are released at offset-centreline positions with zero velocity and settle under gravity, they fall down vertically off the centreline and their orientations tend to be the horizontal finally, and the distances apart from the centreline increase with the increasing charges of the elastic dumbbells.     

Λ超核9Be、6Be和10Be的动力学结构

本文在α集团模型下,利用谐振子基展开和广义Talmi-Moshinsky交换,完成了对Λ超核⁹Be、⁶Be和¹⁰Be能谱的变分计算,借助统一的α-α、Λ-Λ势和修正的Λ-α势,使⁹Be、⁶Be和¹⁰Be能级得到自洽的描述.此外,对上述三个Λ超核的结构和粒子间的关联也作了研究和分析,得到一些有意义的结果.     

椭圆柱体在牛顿流体中运动的格子Boltzmann方法模拟

用格子Boltzmann方法建立了椭圆柱体的二维动力学模型，利用所建立的模型，数值模拟了 牛顿流体中不同形状的椭圆柱体在相同初始条件下的运动和同一椭圆柱体在不同初始条件下 的运动，并通过比较相同条件下圆柱体的运动，讨论了椭圆柱体二维运动的特征，得到了一 些有意义的结果. 关键词： 格子Boltzmann方法 椭圆柱体 牛顿流体     

Lattice Boltzmann simulation of fluid flows in two-dimensional channel with complex geometries

Boundary conditions (BCs) play an essential role in lattice Boltzmann (LB) simulations. This paper investigates several most commonly applied BCs by evaluating the relative L₂-norm errors of the LB simulations for two-dimensional (2-D) Poiseuille flow. It is found that the relative L₂-norm error resulting from FHML's BC is smaller than that from other BCs as a whole. Then, based on the FHML's BC, it formulates an LB model for simulating fluid flows in 2-D channel with complex geometries. Afterwards, the flows between two inclined plates, in a pulmonary blood vessel and in a blood vessel with local expansion region, are simulated. The numerical results are in good agreement with the analytical predictions and clearly show that the model is effective. It is expected that the model can be extended to simulate some real biologic flows, such as blood flows in arteries, vessels with stenosises, aneurysms and bifurcations, etc.     

油桐尺蠖感染核型多角体病毒后血淋巴酯酶的变化

用核型多角体病毒（nuclear polybedrosis virus）感染油桐尺蠖（Buzura suppressaria）四龄初幼虫，以染病后12，24，48，72h分别对幼虫血淋巴进行酯酶同工酶（EST）电泳分析（Native-PAGE),并用薄层扫描仪检测酶带的相对含量，染病幼虫血淋巴的一部分EST含量低于同期对照组，而另一部分却高于对照组；就谱带而言，某些样品酶带在感染后出现迁移率的变化，而有些则出现新的酶带，这二种变化均表现在某一特定的酶带上，提示该酶带在病毒感染的血淋巴病理生化方面可能具有特殊意义。     

双Λ超核_(ΛΛ)~6He和_(ΛΛ)~(10)Be的少体动力学

在α集团模型下，完成了对６ΛΛＨｅ和１０ΛΛＢｅ的变分计算，并研究了各种Λα势和ΛΛ势，借助拟合６ΛΛＨｅ数据所得的修正Λα势与统一的ΛΛ势，获得了超核６ΛΛＨｅ，９ΛＢｅ和１０ΛΛＢｅ的自洽描述。此外，对上述超核的基态结构和粒子关联也作了研究和分析。相互作用矩阵元利用著名的Ｔａｌｍｉ－Ｍｏｓｈｉｎｓｋｙ变换计算     

∧超核_∧~9Be、_(∧∧)~6He和_(∧∧)~(10)Be的动力学结构

本文在α集团模型下,利用谐振子基展开和广义Talmi-Moshinsky变换,完成了对Λ超核_Λ~9Be、_(ΛΛ)~6He和_(ΛΛ)~(10)Be能谱的变分计算.借助统一的α-α、Λ-Λ势和修正的Λ-α势,使_Λ~9Bc、_(ΛΛ)~6He和_(ΛΛ)~(10)Be的能级得到自洽的描述.此外,对上述三个Λ超核的结构和粒子间的关联也作了研究和分析,得到一些有意义的结果.     

用格子Boltzmann方法研究Selkov反应扩散模型中的非线性波

采用五速正方格子模型,对各向同性的平衡分布函数进行推导得到了反应扩散方程。在 零流情况下进行计算机数值模拟,模拟出二维Selkov反应扩散模型的非线性波-环状 波和螺旋波。     

基于纳米金辅助信号生成顺序堆积的毛细管电泳免疫分析研究

短裸甲藻毒素（BTX）是具有极强毒性的生物毒素,能够通过食物链传递引起人类中毒.由于该毒素没有光学和电化学信号,检测十分困难.本工作利用纳米金作为载体,将辣根过氧化物酶（HRP）和毒素抗体同时固定到纳米金表面,通过HRP催化H₂O₂氧化邻氨基酚（OAP）产生的电化学信号检测样品中的毒素,增大纳米金表面HRP和抗体的物质的量比使电化学信号得到极大增强.免疫反应样品电动进样引入分离毛细管中,在毛细管入口端进行顺序堆积在线富集,使检测灵敏度进一步提高.该方法通过纳米金辅助信号生成和顺序堆积在线富集技术实现了对扇贝样品中BTX-B的快速灵敏检测,线性范围为0.1~120 ng/mL,检出限为26 ng/L,检出限比常规酶联免疫分析（ELISA）法低365倍.     

A mass-conserved multiphase lattice Boltzmann method based on high-order difference

The Z–S–C multiphase lattice Boltzmann model [Zheng, Shu, and Chew(ZSC), J. Comput. Phys. 218, 353(2006)]is favored due to its good stability, high efficiency, and large density ratio. However, in terms of mass conservation, this model is not satisfactory during the simulation computations. In this paper, a mass correction is introduced into the ZSC model to make up the mass leakage, while a high-order difference is used to calculate the gradient of the order parameter to improve the accuracy. To verify the improved model, several three-dimensional multiphase flow simulations are carried out,including a bubble in a stationary flow, the merging of two bubbles, and the bubble rising under buoyancy. The numerical simulations show that the results from the present model are in good agreement with those from previous experiments and simulations. The present model not only retains the good properties of the original ZSC model, but also achieves the mass conservation and higher accuracy.