On 28/7/2019 the graduate student (doctorate) "Zena AbdulAmir Salman AlJanabi" discussed her thesis entitled

"Manufacture of Triple Metal Oxides Gas Detector for Diagnostic Medical Applications"

The discussion committee consisted of the following gentlemen:

Abstract

This thesis describes the use of semi-conductive gas detectors to diagnose diseases (kidney failure, colonic emphysema and asthma) that may serve as a portable instrument that diagnoses the components of breathing air to manufacture a detector. Three different metal oxides prepared using thermal spray technology developed using two spray nozzles. A laboratory system prepared for the manufacture of oxide membranes using tungsten salt as a base salt with four additives of tin, zinc, iron and chromium in three weight ratios (3: 1, 1: 1, 1: 3) at a concentration of 0.1 molar using water as a solvent. The salts were sprayed separately at the same time on a heated silicon base followed by heat treatment at (400C 400) for one hour.

A series of tests were carried out for these prepared oxides, including synthetic tests, including the electronic scanner (SEM) to study the morphology of the surface of the samples. X-ray diffraction (XRD) tests were also conducted to obtain the structural information of the samples, the electronic power microscope (AFM) and the optical tests (UV-Visible) to determine the energy gap and Hall effect tests to determine the type of conductivity of the oxides prepared. A system of sensitization tests was used to sensitize ammonia, hydrogen, and carbon monoxide at concentrations (5, 20 and 5) ppm respectively to measure and compare the sensitivity and response time of samples at different temperatures (25, 100, 200 300 ˚C). In dry air. The effect of moisture at 80% at different temperatures for all samples without gases was studied. The results of XRD showed the formation of trioxides (SnWO4, ZnWO4, FeWO4) had different crystalline structures. The results of the scanning electron microscope revealed different microscopic structures (granules, gaps, rods and small needles) with a homogeneous surface. The lowest response was to ammonia gas for all samples, and the sensitivity was improved by the presence of additives due to the formation of microscopic structures with a high surface area with a rough surface that makes them suitable for sensing the lowest concentration of gases. Therefore, they were selected to manufacture portable reagents in disease detection ( Renal failure, flatulence and asthma) respectively.

The controlled gas detector is manufactured using a 3D printer by connecting the prepared reagents with the DAQ panel to process the response values ​​and converting them into an external electrical signal and translating it into a digital signal, where the patient's condition (normal or abnormal) is determined for each detector.

The thesis was evaluated scientifically by Asst. Prof. Dr. Shatha Kazem Abdul Latif / University of Baghdad / College of Engineering Al-Khwarizmi, and evaluated linguistically by Asst. Prof.Dr. Samir Ali Amin / University of Technology / Department of Mechanical Engineering.

The discussion took place in a scientific atmosphere at the Graduate Hall of Building C / Materials Engineering Department / University of Technology the Grad student was awarded Pass with Credit after doing the required corrections done by the committee