Cardiac imaging with multiple-row detector computed tomography (CT) has become possible due to rapid advances in CT technologies. Images with high temporal and spatial resolution can be obtained with multiple-row detector CT scanners; however, the radiation dose associated with cardiac imaging is high. Understanding the physics of cardiac imaging with multiple-row detector CT scanners allows op...

The imaging characteristics of an arc-shaped xenon gas ionization chamber for the purpose of megavoltage CT imaging were investigated. The detector consists of several hundred 320 microm thick gas cavities separated by thin tungsten plates of the same thickness. Dose response, efficiency and resolution parameters were calculated using Monte Carlo simulations. The calculations were compared to m...

Copper layers of Printed Circuit Board (PCB) have been used as electrodes for PbS infrared structure detector to introduce low cost and simple in preparation. PbS deposition as an active layer detector has been prepared for a few micrometers in thickness using an evaporation technique under vacuum pressure at 10 Torr. Photoconductivity phenomenon has been observed from the measurement when IR r...

abstract   background : the application of du emanation for first time contaminated certain areas in the south west region of iraq after the second gulf war (1991). these contaminated areas were discovered in 1994. radioactive contamination was detected using the nuclear enterprise pcm5/1 in soil samples collected from two regions near by grazing lands. this study was done for assessment of du ...

The NDIR gas detection method is based on the absorption of infrared radiation, which is shown by many polyatomic or heterodimer diatomic gases. For example CO2 gas absorbs IR radiation at 4.26μm wavelength. The detected radiation intensity at this wavelength decreases if the concentration of CO2 increases between source and detector. The extent of absorption mainly depends on the absolute numb...

the harmful effects of the long-term ocular exposure to cumulative levels of infrared radiation (ir) in glassblowing and foundries have been recognized since the late 19th century. these effects include cataracts, keratitis, and chronic dry eye problems. therefore, infrared radiation measurements are critical and need to be assessed regularly in the industries and workplaces where there are hig...

Background: High level radiation areas have been recognized on various parts of the earth. Mahallat hot spring region is one of these areas. Study of exposure in these areas can be helpful in investigating the effects of ionizing radiation. Internal and external exposure to the staff was studied. Materials and Methods: Used materials and instruments include: RSS-112 ionizing chamber fo...