Sharif Digital Repository

Considering the advantages and disadvantages of reported micropumps, we aimed to introduce a novel idea to diminish the disadvantages and promote the advantages of PiezoElectric micropumps. This novel idea operates based on a mercury slug actuation in a microchannel. This cyclic motion of the mercury slug which is similar to a piston, push the fluid in the microchannel and pump the flow. However, to bring this idea into the practice, a control system must be designed. This system contains: LABVIEW code, DAQ board & a switching Board. The pattern of actuating mercury is drawn in LABVIEW. DAQ Board produces electrical signals according to LABVIEW code. Switching board will transform the... 

Lithium has two stable isotopes naturally including 6Li at 7.5% and 7Li at 92.5% relative abundance. In spite of the similarities of lithium isotopes in common chemical reactions, they have some completely distinctive behaviors in nuclear reactions. 6Li has considerable neutron cross section capturing in thermal neutron range about 945 barns while this feature for 7Li is insignificant about 0.037 barns. This difference makes them to play different roles in nuclear uses. 7LiOH is applied for pH adjustment of coolant in light water reactors. 6Li is not only used as a shielding material against thermal neutrons, but also is known as a source of tritium in the blanket of fusion reactors which... 

As today's tremendous advance occurred in biotechnology and nanotechnology, the microfluidic devices made a new success that was not possible with the traditional equipments. It was useful in such a way that by using a microliter volume of that fluid, we could have the ability to use it in biologics, medicine, aerospace, cooling electronic systems and medical discovery. One of the main component of fluidic microsystems are micropumps in which they divide into two types. Reciprocating micropumps have been worked by stimulating electromagnetic micropumps which is based on Lorentz law. In this project, we try to investigate the impact of effective parameters in the movement of the mercury mass.... 

Detection and determination of ultra-trace electroactive materials using electrochemical methods have been widely employed by researchers since they offer a fast, easy and reliable approach. In this way, developing of new nanoelectrodes with special and unique properties plays a profound role on the achievement of better results.
Gold nanoelectrode ensembles are one of the most important nanoelectrodes which due to the high surface area, chemical, electrochemical and physical stability, and integration of a large number of individual nanoelectrodes, introduce excellent opportunities to be employed as promising nanoelectrodes in determinations applications.
In this work, preparation... 

In this investigation Magneto Mercury Reciprocating Micrpump (MMRM) the combination of Magneto-Hydrodynamic and Reciprocating micropumps has been analyzed. To achieve the analytical and numerical solution of one-tank and three-tank MMRM, the momentum, continuity, volume fraction and magnetohydrodynamic equations have been presented. The dimensionless analytical solution of one-phase and two-phase three dimensional MHD flow in the condition of using constant current and potential electrical source, has been offered.
The boundary between mercury and air has been tracked via VOF method in OpenFOAM software. VOF equation has been solved by explicit method with variable time step and maximum... 

Design, fabrication and performance of the reciprocating micropumps with actuated fluid slug have been investigated. In these micropumps, pumping principle is based on reciprocating movement of a fluid slug. The fluid slug must be conductive in magnetohydrodaynamic micropump to be actuated by Lorentz force and have good magnetic properties in ferrofluidic micropumps to be actuated by an external magnetic field.
On the other hand, a theory is developed in ahead of design and fabrication process to diagnose the critical and the most influential parameters. Magnetohydrodynamic micropumps in 4 distinict design using nozzle-diffuser element, passive ball valve and active mercury valve have... 

The efficiencies of perovskite solar cells have increased rapidly in recent years and reached about 22%. Which hopes to make this type of solar cell more functional. In the normal structure of perovskite solar cells, the presence of mesoporous TiO2 mesoporous layer has increased sustainability and efficiency. To create this layer, a common method is placing the sample in a furnace for 30 minutes at 450°C-500°C. Using the furnace, in addition to being time consuming, has a high energy consumption. In this study, we tried to create a TiO2 mesoporous layer with the help of lighting. To create TiO2 mesoporous layer, What causes porosity in the layer is the removal of ethyl cellulose and create...