安琪 , 潘绍丰 , 栾兴龙 ,
生命现象中存在许多复杂的时空调节机制，以便对一些生物活性因子进行合理分配。其中，最为常见的是动态的时空浓度梯度，即随着时间积累，空间各处浓度将不断地发生变化；这一过程对于生物体来说是十分重要的。 本文受生物体系中，扩散过程中快速可逆的超分子结合作用调控浓度梯度的启发，报道水凝胶材料中快速可逆超分子结合调控物质浓度梯度的概念。在接有环糊精的水凝胶基质中，客体分子偶氮苯的扩散受超分子结合的影响，产生与自由扩散不同的浓度梯度分配。 模拟过程运用了 COMSOL Multiphysics 5.2中化学反应工程下的稀物质传递模块。建立一个长 5mm、宽 2mm、高 0.5mm的三维几何体，作为水凝胶基底的模型。然后将 2*0.5mm 截面的某一面设置为具有恒定浓度的边界，其物质为对氨基偶氮苯，作为对氨基偶氮苯溶液与水凝胶的边界；对氨基偶氮苯的两种顺反异构体与 beta ...
J. E. Toney
Pennsylvania State University Electro-Optics Center, Freeport, Pennsylvania, USA
We demonstrate the use of Comsol Multiphysics with Matlab to model signal generation in wide-bandgap semiconductor radiation detectors. A quasi-hemispherical detector design is compared with a simple, planar detector. Results show that the quasi-hemispherical design can simply and effectively compensate for the poor hole transport of most compound semiconductor materials.
P. Masson, and R. Meinke
Advanced Magnet Lab, Palm Bay, Florida, USA
Superconductors have the unique capability of trapping magnetic flux. This feature has the potential to enable and improve several applications including high power density rotating machines. Current material used as trapped flux magnets (TFM) is single domain YBCO that present numerous limitations interms of performance, stability and size. One way to overcome the limitations is to use thin ...
P. Krastev, and B. Tracey
Neurometrix, Inc., Waltham, Massachusetts, USA
Nerve localization is important for applications in regional anesthesia. Localization is achieved by stimulating the nerve with an electric field produced by a current from a needle inserted into the body of the patient, close to the target nerve. Modeling of the electric field in close proximity to the nerve may help to explain observed variations in threshold currents and can help to ...
R. Viola, F. Zama, M.Tuller, and E. Mesini
DICMA, University of Bologna, Bologna, Italy
Dep. of Mathematics, University of Bologna, Bologna, Italy
Dep. of Soil, Water, and Environmental Science, University of Arizona, Arizona, USA
Advances in visualization and discretization of pore structures by means of Computed Tomography, and rapidly increasing computational capabilities, allow numerical modeling of pore-scale fluid flow based on the incompressible Navier-Stokes equations rather than using a macroscopic approach based on Darcy’s law. To test the capabilities of the COMSOL Multiphysics modeling platform, we ...
L. Braci, S. Ognier, and S. Cavadias
Laboratoire de Génie des Procédés Plasmas et Traitements de Surfaces, Ecole Nationale Supérieure de Chimie de Paris, University Pierre et Marie Curie, Paris, France
Non-thermal plasma, generated in atmospheric pressure discharges, has been investigated in our laboratory in order to treat highly diluted (300 ppm to 1000 ppm) volatile pollutant. The collision of electrons created in the discharge with atmospheric air, leads to the formation of reactive species that can totally or partially oxidize the pollutants at near ambient temperature. The purpose of the ...
G. Jehle, D. Kern, and W. Seemann
Karlsruhe Institute of Technology (KIT), Karlsruhe, Germany
This paper proposes the design of a 3-Degree of Freedom(DoF) motor based on surface acoustic waves in elastic solids. The rotor is propelled by wave fields, for linear and rotational motion respectively, in the stator, that can be steered by the driving signal of the piezoelectric actuators, which are placed on an elastic plate. The next considerations concern the feasibility of the proposed ...
S. Lazzari, A. Priarone, and E. Zanchini
DIENCA, University of Bologna, Bologna, Italy
A numerical investigation of the long-term performance of double U-tube borehole heat exchanger (BHE) fields, in the case of non-negligible effects of groundwater movement, is performed by means of COMSOL Multiphysics. Two time periodic heat loads, with a period of one year, are studied: Q1, with a partial compensation between winter heating (principal load) and summer cooling; Q2, with no ...
Fudan University, Shanghai, China
COMSOL Multiphysics is a powerful tool in theoretical study. Lei Zhou, Jiping Huang and other professors in Physics Department, Fudan University have achieved some exciting results of soft, tunable metamaterials. We use it to study non-equilibrium behavior of rhoeological (ER) fluids and polar molecule dominated rheological (PM-ER) fluids. Numerical solutions using the Onsager’s principle would ...
Using Comsol 4.1 to Build a Transient Model of a Drift Tube Ion Mobility Spectrometer with Improved Performance
J. Langejürgen, P. Cochems, U. Günay, M. Allers, and S. Zimmermann
Leibniz University Hannover
An Ion Mobility Spectrometer is a device to analyze different components of a gas mixture. A feature of this technology is the ultra-low detection limit which can be obtained for most trace gases. Due to a limited resolution which is needed to differ between different components an improvement of the IMS field geometry is needed. Especially for novel ionization sources the influence of Coulomb ...