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The study was carried out to determine radioactivity concentrations in surface soil samples of the city of Edirne in connection with the potential radiological hazards due to Chernobyl event. The natural radionuclide ((226)Ra, (232)Th and (40)K) contents were determined for nine dierent locations in nine dierent towns of the Edirne city. Radiation levels were measured. Natural beta-ray activity was also determined for the same locations. The average estimated activity values were determined and compared with reported values for other cities in Turkey and also for many countries of the world. The studied areas do not pose radiological risks to the inhabitants due to harmful eects of the ionizing radiation from the natural radioactivity of the soil.

One of the most widely used structural materials in radiation shielding is concrete. Addition of metal particulates to concrete to enhance its density can be used for gamma and X-ray shielding purposes. In this study radiation shielding performance of concrete containing different amounts of iron filling were evaluated using Betatron X-ray radiation source. For this purpose concretes were produced by adding iron filling in the ratios of 0%, 10%, 20%, 30% (in weight) to the cement. CIT/7.5 Betatron source which is a compact, circular electron accelerator, generating directional X-ray beam, was used in this study. Experiments were performed by using conventional radiography test. The results were compared with results for normal concrete. It was observed that the film density differences between the iron filling and normal concrete are in the range of about 10–60%.

One of the most important parameters in a pipeline to be monitored and measured is the wall thickness. Pipe wall thickness can vary after a certain period of time, as a result of accumulation of various chemical or physical e ects. Pipe wall thickness can be monitored by the proper use of ultrasonic or radiographic inspection methods even while the plant is in operation. Only the radiographic method assures inspection without costly removal of insulation material during operation of the plant. The purpose of this study is to de ne the wall thickness of pipes by using digital radiography technique. The outer diameter of the studied pipes is ranging from 51 mm to 60.3 mm and wall thickness is ranging from 2.9 mm to 3.6 mm. Experiments were repeated by changing the focal detector distance and pulse parameters.

In this study, the in uences of B4C ratios on some mechanical and physical properties such as relative density, microhardness and electrical properties of cold pressed Cu-B4C composites were investigated. Curve tting is applied for the estimation of electrical conductivity. Commercial copper powders with 40 μm particle size were reinforced with B4C, with particle size of 40 μm, at ratios of 1, 2, 3 wt.%, for improving mechanical properties of copper used as electrical conductor. Cu-B4C composites have been fabricated by powder sintering process at a temperature of 900 ◦C for 2 h. The presence of Cu and B4C, which are dominant components in the sintered composites, were con rmed by X-ray di raction analysis technique and SEM-EDS. Scanning electron microscope (SEM-EDS) has shown that B4C particles are distributed homogenously in the copper matrix. The relative densities of Cu and Cu-B4C composites, sintered at 900 ◦C, ranged from 95.7 to 91.6%. Microhardness of composites ranged from 84.5 to 94.6 HB. It was observed that cold pressed Cu-1 wt.% B4C composites revealed promising physical properties. Results of electrical conductivity measurement of Cu-B4C composite material are compared to the results of the model and the overall accuracy level above 96% is obtained.

In this study, gas nitriding behavior of 34CrAlNi7 10 steel was investigated. Single stage processes were carried out at 500 ◦C, 520 ◦C and 540 ◦C for 10, 20, 30 h, respectively. Nitrogen activity on surface was controlled by the nitriding potential KN which is known as thermodynamical control parameter for controlled gas nitriding process. The presence of nitrides formed on surface of test material was determined by X-ray di raction analysis technique. The morphology of nitrided layer was studied by optical microscope. The microhardness of surface of nitrided sample in HV1 was observed between 975 and 1132. Choosing the right nitriding potentials for each temperature, which give the same nitrogen concentration and activity on surface by using the Lehrer diagram, showed that all the samples had almost the same surface roughness of Ra = 0.28 0.32 μm after gas nitriding cycles. The measurements showed that the white layer thickness varies between 4.38 μm and 28.80 μm and the growth of the layer was strongly a ected by process time and temperature. Di usion depths as Nht (HV) for each experiment were determined and compared.