Journal of Kufa - physics

In the past quarter century, applications of fluorescence resonance energy transfer (FRET) have grown dramatically, and the technology has become an indispensable tool in a wide variety of biological and biophysical domains. It is utilized, in order to acquire information on the conformational changes that occur in single molecules. By utilizing the fluorescence correlation spectroscopy, the pharmaceutical sector has also built huge fluorescence detection systems with extremely small sample sizes, reachingdown to the level of single molecules. The fluorescence resonance energy transfer (FRET) between the two dyes, Acriflavine (Acf) and Rhodamine B (RhB), were examined in solution. Energy transfer was observed in fluorescence resonance imaging solutions containing Acriflavine and Rhodamine B with different concentrations of the acceptor RhB dye in the range of (1.5×10-5M to 3.5×10-5M). Studies using Both UV–Vis absorption and fluorescence spectroscopy demonstrated that the two dyes, when dissolved in solution, appear largely as monomers.

In this study, the ratio method between the two spectral lines was used to calculate the electron temperature (Te) and the density (ne) of argon gas for a zinc oxide (ZnO) cathode using the spectroscopic method. These parameters were calculated at various pressure and powers parameters (0.03,0.04,0.05,and 0.06 torr) and (50,60,70 and 80 W). The results revealed that while the temperature (Te) increase of the electron with increased power and falls with increasing pressures, the density (ne) of the electrons increases with both power and pressure increases. The measured temperature of the electrons (Te) was within the range of (0.372-0.422 eV).Regarding the electron density (ne), it was in the range of(1.6×1017-7.8×1017cm-3).

The optical properties of polyvinyl chloride (PVC) and PVC/Zinc Oxide (ZnO) films were considered with different amounts of ZnONPs(0.001, 0.002, 0.003, 0.004 and 0.005) g. Using a Tetrahydrofuran (THF) solution all films be prepared by casting method. XRD results showed the amorphous structure of PVC film and Hexagonal crystalline structure of ZnO NPs, PVC/ZnO nanocomposites appear as pattern of PVC films so the peaks of ZnO don’t appear in it. FESEM image of PVC, ZnO and structure of PVC/ZnO nanocomposites seems to have cluster aggregates in different size. FTIR spectra revealed that ZnONPs had no effect on the polymer structure as there are no covalent bonds between PVC and ZnO NPs. Increasing the amounts of ZnONPs was seen to improve the optical properties (Absorbance, absorption coefficient and extinction coefficient) for PVC polymer. PVC polymer transmittance and energy gap decreased from 5.25 eV to 4.98 eV with increasing the amounts of ZnO NPs in nanocomposites. The solar radiation intensity in Baghdad was measured at a rate of 1 hour for the pure PVC films and PVC/ZnONPs for seven consecutive days in a rate from 6 A.M. to 6 P.M. (13 h). As can be observed, all films have the same ratio of transmitted radiation strength to sunlight intensity for all hours and days.

This study concentrates on the examination of the functional, electrical, and sensing qualities of ZnTethin films that were prepared by the thermal evaporation method, with a thickness of 300 nm deposited on glass bases prior to annealing at a temperature of (350ºC). The influence of doping with cadmium (7%) on the structural, electrical, and sensing properties of dopant films was also investigated. The results of XRD showed that the pure and doped films were polycrystalline and cubic. According to the findings of the electrical properties of this study, the specific resistance decreases with increasing temperature. It was found that the sensitivity of ZnTe films rises upon doping and annealing, so the sensitivity was calculated.

HA (hydroxyapatite) is considered one of the biomaterials widely, it is applied in many applications like the medical and dentistry. In this research, NHA powder was prepared from some natural source rich in calcium carbonate, it was prepared by calcination method at 1200 °C for 2 hours. The samples were diagnosed by using various diagnostic tests including scanning electron microscopy (SEM(, X-ray diffraction (XRD), Fourier transform infrared (FTIR), X-ray spectroscopy (EDX), and the density measurements. The XRD results showed that HA as-prepared high purity and the crystallite size as around 63.561± 11.327nm, while the particle sizes≈ 63nm according to BET,also EDX clearly showed elements (Ca, P, O). As for the density of NHA, it was measured and found to be equal to (2.98±0.1) g/cm3. Characterization results (XRD, SEM, EDX, FTIR, and BET) showed that the morphological and structural properties of the Hydroxyapatite

The goal of this study was to examine the impact of using additional aluminum (Al) and copper (Cu) filters on radiation dose during the adult chest x-ray examination. Adult chest phantoms without and with different slabs of animal fat were used for simulating underweight, overweight, and obese patients, respectively. Phantoms were examined without and with various levels of extra Al and Cu filtering over a range of exposure parameters. A dose area product (DAP) meter was usedto measure the radiation dose. Results demonstrated that radiation doses were significantly reduced (p=0.001) when applying extra filters compared with no filters for all of the different phantom sizes. The highest reduction in radiation dosage was 38, 41, and 42 percent for underweight, overweight, and obese phantom size, respectively, by 1mm Al+0.2mm Cu. In conclusion, the use of extra filters in chest x-ray imaging provides an optimal dose reduction choice regardless of the thickness of the chest region to be radiographed

In this work, optical fibers were designed and implemented as a medical sensor based on surface Plasmon resonance (SPR) to estimate different refractive indices and (Candida) concentrations and improve the endoscope's performance. Using multi-mode and single-mode optical fibers deposited by 40 nm thickness gold metal deposition for the sensing area, In practice, it was found that when the refractive index of the sensitive medium increases, the length of the resonant wave increases due to the decrease in energy.

Differential electron elastic scattering cross sections are attained by ammonia and phosphine molecules for 15 eV to 500 eV and 5 eV to 500 eV, respectively. The required calculations were done with the use of partial waveforms characterizing the target molecule and a single Hartree-Fock Molecular Function Center. Results from this model make evident the significance of the exchange, as well as the contributions of correlation and polarization, particularly at low scattering angles and incident energy, because the potentials utilized contain a constant part—numerically generated through quantum computing. Good agreement was discovered between the calculated differential cross sections and a wide database of experimental data. Different spherical scattering angles and power spectrums are analyzed in this paper.

In this work, a fiber-optic biomedical sensor was manufactured to detect hemoglobin percentages in the blood. SPR-based coreless optical fibers were developed and implemented using single and multiple optical fibers. It was also used to calculate refractive indices and concentrations of hemoglobin in blood samples. An optical fiber, with a thickness of 40 nanometers, was deposited on gold metal for the sensing area to increase the sensitivity of the sensor. The optical fiber used in this work has a diameterof 125μm, no core, and is made up of a pure silica glass rod and an acrylate coating. The length of the fiber was 4cm removed buffer and the splicing process was done. It is found in practice that when the sensitive refractive index increases, the resonant wavelength increases due to the decrease in energy.

The nanofiber membranes prepared by electrospinningmethod attracted the attention of researchers in the field of pollutant treatment due to their ease of manufacture, efficient performance and ease of removal. Some of these membranes lack the possibility of reuse due to low efficiency and high regeneration cost. In this paper, we were able to prepare nanofiber membranes from polyacrylonitrile (PAN) and PAN/TiO2by adding different ratios (5,10 and 15) wt% of TiO2respectively. The resultants nanofibers were characterized using Field Emission Scanning microscope (SEM), Fourier Transform Infrared spectroscopy (FTIR). This prepared membranes enable effective and complete degradation of MB dye in water using ultraviolet (UV) irradiation with the possibility of reuse and high efficiency after washing with distilled water. The efficiency is up to 98% when 15wt% TiO2was used, while the degradation reaches to 83% when reused the nanofibers composite (PAN/TiO2). The work not only explains the possibility of using and reusing nanofiber films in the treatment of pollutants, but also gives a detailed of understanding the behavior of the membrane in dye degradation