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In recent years, forming a 3D microfluidic channels on the electrical non-conductive material such as Polydimethylsiloxane (PDMS) in the micro-electromechanical system (MEMS) and medical applications is of great interest. Lithography is the most know process to create patterns on the PDMS however there are a few drawbacks to this process such as high operational cost and time, and sidewall angle. In all applications, the quality of the micro-channel surface determines the performance of it. In this research as innovatively the electrochemical discharge milling (ECDM) which is known for lower operational cost and proper material removal rate (MRR; i.e. process time), and is capable of creating patterns on electrical non-conductive material, was used to form a micro-channel on the PDMS. To that end, the effect of process parameters such as electrolyte concentration, feed rate and cutting speed and voltage on the surface roughness and surface integrity deeply investigated. It was observed that ECDM is capable of creating patterns on the PDMS with surface integrity which is comparable with the lithography microchannel. It is also observed that decreasing the rotational speed from 10000 to 0rpm results in increasing the surface roughness 2 to 4 times. This happens due to the increasing the thickness of the gas film around the tool, and subsequently increasing the flying sparks which results in higher surface roughness. Increasing the Voltage from 38 to 42V results in 36% enhancement of surface roughness. The 25% electrolyte concentration results in lower surface roughness. [ABSTRACT FROM AUTHOR]

The moisture content of the beans and the pods of the green beans were determined and the samples were then subjected to ohmic pretreatment at the specified levels. For this purpose, force-deformation device was used. Static loading was performed to determine the mechanical properties of the pretreated specimens. Experiments were carried out in a completely randomized design with factorial experiment. The effect of ohmic heating parameters at three time levels of 3,6 and 9 minutes and three voltage levels of 30,50,70 V and for vertical loading at one surface was investigated. The results showed that both factors (ohmic heating time and voltage value) had a significant effect on fracture force and other mechanical properties, so that with increasing ohmic heat duration the amount of fracture force and other mechanical properties decreased. The result of the loading was that in the fracture force section of the grain the maximum value of 3 minutes was 30 V with a value of 19.193 N and the lowest value was 9 minutes with a voltage of 70 grain equal to 5.58 and in the discussion of grain failure energy the highest and The lowest values were 21.622 N and 5.77 N respectively, which were 30 V and 3 min for maximum and 70 V and 6 min for minimum. In the discussion of the fracture force of green bean pod with grain the highest value was 30 V and 3 min time equal to 578.13 N and 72.35 N 35 min which was 70 V and 3 min time and also the highest and lowest energy The fracturelike fracture force of this sample at the same time and voltage were 656.49 and 187.38, respectively. [ABSTRACT FROM AUTHOR]