模拟

Abstract(#br)We present a microfluidic chip for cell handling applications fabricated in polydimethylsiloxane (PDMS). The chip was designed to accumulate cells inside a reaction chamber where they can be manipulated under attendance of a liquid reagent (PEG–polyethylene glycol) for cell fusion. To enable the cell handling a fluid management system was developed which includes pneumatically actuated microfluidic valves integrated into the chip. Various valve geometries were simulated in ANSYS and characterized in a series of tests to identify a feasible valve concept.

In this paper we present various pneumatically actuated microfluidic valves to enable user-defined fluid management within a microfluidic chip. To identify a feasible valve design, certain valve concepts are simulated in ANSYS to investigate the pressure dependent opening and closing characteristics of each design. The results are verified in a series of tests. Both the microfluidic layer and the pneumatic layer are realized by means of soft-lithographic techniques. In this way, a network of channels is fabricated in photoresist as a molding master.

高能源需求、竞争激烈的燃料价格以及对环境友好工艺的需要，导致了酒精工业的不断发展。渗透汽化被看作是一种分离过程，能耗低，在乙醇的发酵脱水方面具有很高的应用潜力。本工作给出了渗透汽化回收乙醇的实验和部分通量的半经验模型。在乙醇进料浓度为4 ~ 37 mM ( 1 ~ 9 wt % )、温度为34 ~ 50 μ mol / L ~ ( - 1 )、渗透通量为15.6 ~ 68.6 mol · m ~ ( - 1 ) ~ ( - 1 ) ( 289 ~ 1565 ) g · m ~ ( - 1 ) ~ ( - 2 ) h ~ ( - 1 ) )、分离因子为3.4 ~ 6.4、乙醇摩尔分数为16 ~ 171 mM ( 4 ~ 35 wt % )的条件下，采用商业聚二甲基硅氧烷( PDMS )膜，获得了总渗透通量为15.6 ~ 68.6 mol · m ~ ( - 1 ) ( 289 ~ 1565 ) g · m ~ ( - 2 ) · h ~ ( - 1 )，分离因子为3.4 ~ 6.4。从实验数据出发，综合考虑温度和进料组成的影响，以及表观活化能的行为，建立了描述部分渗透通量行为的半经验模型。因此，所得到的模型显示出一种修正的Arrhenius型行为，能够高精度地计算部分渗透通量。此外，模型在乙醇回收、乙醇和丁醇脱水等过程中显示了通用性。

高能源需求、竞争激烈的燃料价格以及对环境友好工艺的需要，导致了酒精工业的不断发展。渗透汽化被看作是一种分离过程，能耗低，在乙醇的发酵脱水方面具有很高的应用潜力。本工作给出了渗透汽化回收乙醇的实验和部分通量的半经验模型。在乙醇进料浓度为4 ~ 37 mM ( 1 ~ 9 wt % )、温度为34 ~ 50 μ mol / L的PDMS膜上，总渗透通量为15.6 ~ 68.6 mol m-2 h-1 ( 289 ~ 1565 g m-2 h-1 )，分离因子为3.4 ~ 6.4，乙醇摩尔分数为16 ~ 171 mM ( 4 ~ 35 wt % )。从实验数据出发，综合考虑温度和进料组成的影响，以及表观活化能的行为，建立了描述部分渗透通量行为的半经验模型。因此，所得到的模型显示出一种修正的Arrhenius型行为，能够高精度地计算部分渗透通量。此外，模型在乙醇回收、乙醇和丁醇脱水等过程中显示了通用性。