Journal of Kufa - physics

Gold nanorods (GNRs) have emerged as pivotal nanostructures in optical and electronic applications due to their unique localized surface plasmon resonance (LSPR) properties, which are highly sensitive to particle geometry and the surrounding medium. This study investigates the effects of spatial variations, radius of the cylindrical structure, surrounding media, and insulating layers on the scattering behavior of GNRs under illumination at selective wavelengths (610, 710, 810, 910) nm. Three key simulation models were developed: The first simulation model was on the impact of varying interparticle distances in different media (air and water), revealing significant shifts in scattering intensity and plasmonic spectra due to enhanced interactions at closer proximities. The second simulation model explored the role of insulating layers, demonstrating that coatings such as silica altered electric field distributions and attenuated environmental influences, resulting in modified scattering spectra. The third simulation model focused on the impact of varying the radius of GNRs in different media (air and water), again showing notable shifts in scattering intensity and plasmonic behavior. The results clearly highlight the critical role of gold nanoparticles as active nanostructures in controlling the optical response, particularly through the LSPR mechanism. This emphasizes their potential in nanophotonic applications, such as high-sensitivity optical sensors, nanoscale imaging systems, and optoelectronic devices. The findings also show that the maximum benefit of nanostructures in medical fields can be obtained by carefully designing these structures.

Occupational exposure to ionizing radiation from radiology equipment is believed to impact the health of healthcare professionals, particularly those working in radiology departments. This study investigates the long-term effects of chronic X-ray exposure on hematological parameters in radiology staff across multiple hospitals in Raniya City. This cohort study was conducted in six government hospitals in the Raparin district of Sulaimaniyah Governorate. A total of 96 participants were enrolled: 48 radiographers (case group) with prolonged exposure to X-rays and 48 medical laboratory professionals (control group) without such exposure. The study focused on evaluating the correlation between annual radiation dose and changes in the hematological parameters (cases/ controls), including white blood cell (WBC), red blood cell (RBC), and platelet (PLT) counts. A minimum and maximum value of occupational chronic X-ray exposure for the radiographer was 1.69 μSv to 414.27 μSv, respectively. A significant increase in risk was observed when the X-ray dose exceeded 100 μSv. WBC count shows very weak and non-significant negative correlation with radiation dose. RBC count shows strong and statistically significant negative correlation, suggesting radiation exposure is associated with lower RBC counts. PLT count shows moderate and significant negative correlation, indicating platelet counts tend to decrease with higher radiation doses

In this research, coating mixtures of several percentages were prepared using aluminium oxide or alumina powder AL2O3. Pieces of petroleum derivatives pipes were selected and formed with equal dimensions (2x2x2) mm with a number of (5) pieces. The mixtures were prepared using the liquid mixing method and ultrasonic technology to stimulate the composites (coatings) from a percentage of (5%) to a percentage of (20%) of (AL2O3). Then they were mixed and added to the paint used in coating the pipes by immersion. The Tafel method was used to calculate the corrosion rate (electrochemical method) and the soil immersion method, and the results were compared between the two methods. The results showed a significant improvement for the samples reinforced with a percentage of (10%), the lowest corrosion rate, compared to the pure model and the coated model free of additives and the rest of the percentages.

In this work, nanostructured zinc oxide were doped with various silver doping ratios of 0%, 2%, 4%, and 8%. The nanorods were grown on silicon wafers using the chemical bath deposition (CBD) method. Aluminum contacts were evaporated onto the prepared samples using a thermal evaporation technique. Al/Ag:ZnO/Si/Al detectors were produced according to the above ratios, and were named as X1, X2, X3, and X4, respectively. The structural properties and surface morphology of the fabricated detectors were studied. The effect of (I-V) and (I-T) was also studied at a room temperature. The current values at UV wavelengths of 365 nm and 385 nm showed a distinct difference between the synthesized detectors. The photosensitivity values of the detectors based on Ag:ZnO composition (i.e. 0%, 2%, 4%, and 8%) under an applied source voltage of 5 V for samples X1, X2, X3, and X4 were 413%, 9722%, 2055% and 753% at a wavelength of 365 nm, and 444%, 4810%, 930% and 602% at a wavelength of 385 nm in UV light and a power density of 40 μW/cm², respectively. By calculating the rise and decay time for each sample and at each UV wavelength of 365 nm and 385 nm, it was found that the effect of doping was effective and good in improving and developing the prepared detectors. All detectors exhibited stability and high-speed response, especially for the extinction time.

In this study, a poly[(9,9-dioctylfluorenyl-2,7-diyl)-co-(4,4′-(N-(4-sec-butylphenyl) diphenylamine))] (TFB) polymer was added to silver oxide (AgO) thin films to increase their sensitivity. The S2 (TFB/AgO) sample demonstrated the highest sensitivity of 172.6% at an operating temperature of 150 °C and the shortest recovery time of 6 s at 25 °C and 200 °C. The composite films showed the biggest change in electrical resistance. Pulsed laser deposition (PLD) was used to deposit AgO thin films on glass and quartz substrates, and spin coating was used to deposit TFB polymer layers to create uniform films. AgO has a polycrystalline cubic structure, and the addition of TFB did not change this crystal structure, according to X-ray diffraction (XRD) analysis, which verified that TFB is amorphous. The TFB/AgO sample displayed dominant AgO absorption in the optical absorption spectra, while the polymer encasing the AgO particles made TFB absorption more noticeable in the TFB:AgO mixed film. Both AgO and TFB were identified by Fourier-transform infrared (FTIR) analysis, which showed distinct absorption peaks with observable shifts and intensity variations in the composite samples. The interaction between TFB and AgO and the creation of altered interfacial bonds are confirmed by these spectral shifts.

In this study, nanocomposite films of titanium oxide (TiO2) were prepared on Si plates by hydrothermal method at high temperatures (i.e.150 °C, 160 °C and 170 °C) with the concentration of titanium oxide was fixed at 0.75 ml and the deposition time constant at 6 h. These films were prepared by adding 0.75 ml of titanium butoxide (TiO2), 20 ml of hydrochloric acid and 40 ml of deionized water. The heat treatment was carried out at 450 °C for 2 hrs. UV-vis tests were performed on FTO samples (T1, T2 and T3) at different temperatures, when the absorbance and energy gaps of the samples were studied. XRD examinations showed the peaks of each sample, and FESEM images also showed the shapes of nanorods for all samples. With using a photoluminescence device, it was found that the photoluminescence value was concentrated at (415 - 405 nm) in the samples prepared with TiO2, and its intensity was observed to increase with increasing temperature. Si/TiO2 photodetectors prepared at different temperatures. The sensitivity (844%, 500% and 440%) and photoresponse (0.0152, 0.0075 and 0.00585 A/W) were obtained for the temperatures (150 °C, 160 °C and 170 °C), respectively. These parameters were calculated using UV light with a wavelength of 385 nm and an intensity of 0.05 mW/cm2 at a room temperature, applying a bias voltage of 3 V, consistent with the electrical configuration used during photoresponse measurements with an on time of 20 s and off time of 20 s. These rays were incident perpendicularly on the photodetectors at a distance of 5 cm. In this study, we will focus on the best results obtained from the measurements.