3D integrated microfluid devices are a group of engineered microelectromechanical systems (MEMS) whereby the feature size and operating range of the components are on a microscale. These devices or systems have the ability to detect, control, activate, and create macroscale effects. On this basis, microfluidic chips are systems that enable microliters and smaller volumes of fluids to be controlled and moved within microscale-sized (one-millionth of a meter) channels. While this small scale can be compared to microfluid chips of larger applications, such as pipes or plumbing practices, their small size is commonly useful in controlling and monitoring the flow of fluid. Through such applications, microfluidic chip technology has become a popular tool for analysis in biochemistry and bioengineering with their most recent uses for artificial organ production. For this purpose, microfluidic chips can be instantly controlled by the human body, such as pulse, blood flow, blood pressure, and transmitting data such as location and the programmed agents. Despite its vast uses, the production of microfluidic chips has been mostly dependent upon conventional practices that are costly and often time consuming. More recently, however, 3D printing technology has been incorporated in rapidly prototyping microfluid chips at microscale for major uses. This state-of-the-art review highlights the recent advancements in the field of 3D printing technology for the rapid fabrication, and therefore mass production, of the microfluid chips.

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With the air leakage test methods, the leakage tests of the products that are required to be leakproof are carried out. This leakage test starts with placing the product on a fixture. The in-ternal pressure is increased by filling compressed air into the product placed in the Fixture. The product is filled with compressed air up to a previously calculated test pressure value. After the test pressure value is reached for the desired product, the air filling process is completed, and the stabilization period begins. At the end of this period, information about the leakage of the product is obtained, depending on whether there is a change in the internal pressure of the product. In order to fill the product with compressed air, there must be an air hole on the product. Products without this air hole cannot be tested with these methods. With the new method we will develop, it will be possible to test the leakage of closed products without atmosphere-air connection.

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In this study, various mechanical behaviors of a shape memory alloy, depending on different thermal and electrical conditions to be used in areas such as biomedical, aerospace and aeronautics. Temperature changes and length change rates under different electrical current values of a shape memory alloy named "nickel titanium", or "nitinol" (NiTi) has been observed. It has been seen that a 0.3 mm diameter wire can generate a force of 25 N while the material extends its linear measurement with a rate of 3.7 mm/s. It is observed that, under diverse constant electrical current values, the displacement and temperature relations of the nickel titanium wire is varying. It has empirically been seen that the nickel titanium alloy actuators are advantageous than their alternatives in terms of the generated strength to weight ratio and shape memory alloy materials can be used as actuators in industrial and biomedical applications.