On the vanishing dissipation limit for the incompressible MHD equations on bounded domains

In this paper,we investigate the solvability,regularity and the vanishing dissipation limit of solutions to the three-dimensional viscous magnetohydrodynamic(MHD)equations in bounded domains.On the boundary,the velocity field fulfills a Navier-slip condition,while the magnetic field satisfies the insulating condition.It is shown that the initial boundary value problem has a global weak solution for a general smooth domain.More importantly,for a flat domain,we establish the uniform local well-posedness of the strong solution with higher-order uniform regularity and the asymptotic convergence with a rate to the solution of the ideal MHD equation as the dissipations tend to zero.     

Flow-injection chemiluminescence determination of aminomethylbenzoic acid and aminophylline based on N-bromosuccinimide-luminol reaction

A novel and sensitive chemiluminescence (CL) method for the determination of aminomethylbenzoic acid and aminophylline coupled with flow-injection analysis (FIA) technique is developed in this paper. It is based on the inhibition effect of the studied drugs on the chemiluminescence emission of N-bromosuccinimide-luminol (NBS-luminol) system. Under the optimum conditions, the decreased CL intensity is linear with the concentration of aminomethylbenzoic acid in the range of 2×10⁻⁸ to 1.0×10⁻⁶ g ml⁻¹ and with the concentration of aminophylline in the range of 1×10⁻⁷ to 7.0×10⁻⁶ g ml⁻¹, respectively. The detection limit is 7.0×10⁻⁹ g ml⁻¹ for aminomethylbenzoic acid (3σ) and 3.4×10⁻⁸ g ml⁻¹ for aminophylline (3σ). The relative standard deviations (R.S.D.) for 11 parallel measurements of 2.0×10⁻⁷ g ml⁻¹ aminomethylbenzoic acid and 1.0×10⁻⁶ g ml⁻¹ aminophylline are 2.6 and 3.0%, respectively. The proposed methods have been applied for the determination of the studied drugs in their pharmaceutical formulations with satisfactory results. The possible use of the proposed system for the determination of aminomethylbenzoic acid in plasma sample was also tested. The possible inhibition mechanism of aminomethylbenzoic acid and aminophylline on luminol-NBS system was discussed briefly.     

GLOBAL EXISTENCE OF WEAK SOLUTIONS TO THE NON-ISOTHERMAL NEMATIC LIQUID CRYSTALS IN 2D

In this article, we prove the global existence of weak solutions to the nonisothermal nematic liquid crystal system on T2, on the basis of a new approximate system which is different from the classical Ginzburg-Landau approximation. Local in space energy inequalities are employed to recover the estimates on the second order spatial derivatives of the director fields locally in time, which cannot be derived from the basic energy balance.It is shown that these weak solutions satisfy the temperature equation, and also the total energy equation but away from at most finite many "singular" times, at which the energy concentration occurs and the director field losses its second order derivatives.     

PREFACE

正This special issue of Acta Mathematica Scientia is dedicated to Prof.Boling Guo on the occasion of his 80thbirthday.Prof.Guo was born in Longmen town,Xinluo district,Longyan city,Fujian province,China.After graduating from the Longyan No.1 High School,he was admitted into the Department of Mathematics,Fudan University where he worked after graduation until 1963.In 1963,he moved to Beijing Institute of Applied Physics and     

Pyrazole-based trinuclear and mononuclear complexes: synthesis,characterization, DNA interactions and cytotoxicity studies

Transition Metal Chemistry - A new trinuclear Cu(II) complex [Cu3(μ3-OH)(μ-pz)3(Hpz)2(HCOO)(BTAO)Cl] (1) (Hpz = pyrazole, BTAO = 4,6-bis(dimethylamino)-1,3,5-triazin-2(1H)-one) and four...     

GCr15钢-CVDCr_7C_3镀层摩擦副摩擦振动的研究

本文系统地研究了GCr15钢球-CVDCr_7C_3镀层钢盘摩擦副滑动干摩擦引起的摩擦力(切向力)振动特性及其对材料摩擦磨损性能的影响。试件系统在垂直和水平方向上均处于低刚度、小阻尼状态。试验信号由微机采集、处理并进行频谱分析。结果表明,摩擦力振动的类型与正压力有关,而与拖动速度无关;摩擦力呈周期性自持振动时具有与相对滑动速度典型的非线性关系,振动频率接近(略低)于系统在切向的固有频率,而与拖动速度无关;摩擦力呈非平稳随机振动时,振动频率与系统在法向的振动频率有关,而与系统在切向的固有频率及拖动速度都无关;摩擦偶件运动的平稳性与摩擦力振动的类型有关,而与平均摩擦系数无关;摩擦力所耗费的能量与正压力呈比例关系。     

Stability and Existence of Multidimensional Subsonic Phase Transitions

The purpose of this paper is to prove the uniform stability of multidimensional subsonic phase transitions satisfying the viscosity-capillarity criterion in a van der Waals fluid, and further to establish the local existence of phase transition solutions.     

Electrochemiluminescent aptamer biosensor for the determination of ochratoxin A at a gold-nanoparticles-modified gold electrode using N-(aminobutyl)-N-ethylisoluminol as a luminescent label

A highly selective electrochemiluminescent biosensor for the detection of target nephrotoxic toxin, ochratoxin A (OTA), was developed using a DNA aptamer as the recognition element and N-(4-aminobutyl)-N-ethylisoluminol (ABEI) as the signal-producing compound. The electrochemiluminescent aptamer biosensor was fabricated by immobilizing aptamer complementary DNA 1 sequence onto the surface of a gold-nanoparticle (AuNP)-modified gold electrode. ABEI-labeled aptamer DNA 2 sequence hybridized to DNA 1 and was utilized as an electrochemiluminescent probe. A decreased electrochemiluminescence (ECL) signal was generated upon aptamer recognition of the target OTA, which induced the dissociation of DNA 2 (ABEI-labeled aptamer electrochemiluminescent probe) from DNA 1 and moved it far away from the electrode surface. Under the optimal conditions, the decreased ECL intensity was proportional to an OTA concentration ranging from 0.02 to 3.0 ng mL^-1, with a detection limit of 0.007 ng mL^-1. The relative standard deviation was 3.8% at 0.2 ng mL^-1 (n = 7). The proposed method has been applied to measure OTA in naturally contaminated wheat samples and validated by an official method. This work demonstrates the combination of a highly binding aptamer with a highly sensitive ECL technique to design an electrochemiluminescent biosensor, which is a very promising approach for the determination of small-molecule toxins.