Development and construction of rotating polarizer analyzer ellipsometer

A detailed mathematical derivation and an experimental characterization of one to two ratio rotating polarizer analyzer ellipsometer (RPAE) are presented. The alignment, calibration, and testing of reference samples are also discussed. The optical properties of some known materials obtained by the proposed ellipsometer will be shown and compared to accepted values. Moreover, the constructed ellipsometer will be tested using two ellipsometry standards with different thicknesses

Theoretical spectroscopic scan of the sensitivity of asymmetric slab waveguide sensors

An extensive theoretical analysis is carried out to investigate the variation of the sensitivity of optical slab waveguide sensors with the wavelength of the guided wave. We consider a three-layer waveguide as an optical sensor. The sensitivity for both polarizations of light: s-polarized light (TE) and p-polarized light (TM), is derived using the characteristic equation of the structure. The dispersion of the materials is taken into account to study the sensitivity spectroscopic scan over the near IR-range from 1.2–2 µm. It is found that an optimum wavelength exists for each guiding layer thickness and this optimum value increases linearly with the thickness of the guiding layer

Comparing optical sensing using slab waveguides and total internal reflection ellipsometry

The sensitivity of the effective refractive index of slab waveguide sensors to variations in the refractive index of the cladding is compared to that of the ellipsometric parameters. The changes of the effective refractive index of a waveguide and the ellipsometric parameter\Delta, due to the index change of the cladding, were derived and plotted as a function of the guiding layer thickness and with the index of the cladding. It is found that these changes almost have the same overall feature but the ellipsometric parameters showed considerable higher sensitivity than the effective index of the conventional waveguide optical sensors

Rotating polarizer, compensator, and analyzer ellipsometry

In this paper we propose theoretically a set of ellipsometric configurations using a rotating polarizer, compensator, and analyzer at a speed ratio of N 1 ω: N 2 ω: N 3 ω. Different ellipsometric configurations can be obtained by giving different integral values to N 1, N 2, and N 3. All configurations are applied to bulk c-Si and GaAs to calculate the real and imaginary parts of the refractive index of the samples. The accuracies of all ellipsometric configurations are investigated in the presence of a hypothetical noise and with small misalignments of the optical elements. Moreover, the uncertainties in the ellipsometric parameters as functions of the uncertainties of the Fourier coefficients are studied. The comparison among different configurations reveals that the rotating compensator—analyzer configuration corresponds to the minimum error in the calculated optical parameters

Optical Parameters of Varies Thickness of Bismuth (Iii) Iodide Thin Films for Photovoltaic and Nonlinear Applications

We report in varies thickness of BiI3 thin films by thermal evaporation techniques onto glass substrate. The films were strongly oriented along the (113) plane. The structural parameters of these films (crystallite size and lattice strain) were determined using (XRD) pattern. The thicknesses and refractive indices of the films were considered using Swanepoels method. The band gap was determined in terms of T and R spectrum in the UV-region of the absorption. The possible optical transitions of all films are found to be allowed direct transition with energy gap fluctuate bout 1.96 ± 2% eV. Dielectric constant, volume-energy-loss function (VELF) and surface-energy-loss function (SELF) for as deposited films were discussed in terms of film thickness rising. The change in optical parameters have been interpreted in terms of the change in microstructure parameters. BiI3 is recommended for photovoltaics and nonlinear optics because of its higher absorption coefficient, dielectric constant, and fair band gap

Assessment of natural radionuclides and heavy metal concentrations in marine sediments in view of tourism activities in Hurghada city, northern Red Sea, Egypt

The specific activity of 40K, 232Th and 226Ra in marine sediment samples collected from National Institute of Oceanography and Fisheries (NIOF) and Safier Hotel area in Hurghada city (the most important regions in Egypt), were measured by gamma ray spectrometry using NaI(Tl) detector. The values of specific activity varied from 7 ± 1 Bq kg-1 to 53 ± 4 Bq kg-1, 6 ± 1 Bq kg-1 to 32 ± 6 Bq kg-1, and from 167 ± 11 Bq kg-1 to 1120 ± 63 Bq kg-1 for 226Ra, 232Th and 40K, respectively. The heavy metals have been measured and analysed by atomic absorption spectrometer. The major range values of heavy metals concentrations in marine sediment samples were: Cu (10.5-78.0 μg g-1), Zn (21-150 μg g-1), Pb (30-53 μg g-1), Cd (2.50-4.00 μg g-1), Fe (5100-13150 μg g-1), Mn (118-298 μg g-1), Ni (17-36 μg g-1) and Co (16-18 μg g-1). The total organic matter (TOC) and carbonates (CaCo3) distribution have been measured at some locations. Also, the frequency distribution and the value of (232Th/226Ra), (232Th/40K) and (226Ra/40K) ratio for all measured samples were determined. Additionally, evaluations have been made of the radiological hazards and the results are diagrammed by Surfer program in maps. © Penerbit Universiti Sains Malaysia, 2019

Thermoelectricity Based on Cuo as a Semiconducting Material

In this paper, thermoelectricity based on copper(II) oxide CuO as semiconducting material is explored. The electrical properties of the samples were studied under different temperature gradients and pressures. Moreover, the effect of baking temperature was also investigated. CuO prepared using decomposition of Cu(NO3)2 as well as CuO nanopowder prepared using microwave-assisted synthesis technique were investigated and their results were compared. It was found that the current density can be enhanced with increasing the pressing pressure of the sample and when the sample undergoes a baking process. Moreover, it was found that the current density can be considerably enhanced with increasing the temperature gradient between the two ends of the sample. The CuO prepared using microwave-assisted synthesis technique was found to exhibit much better results over those of the CuO prepared using decomposition of Cu(NO3)2

Prevalence of blighted ovum in first trimester of pregnancy: a hospital based study

Background: The aim of this study is to know the prevalence of blighted ovum among pregnant women in 1st trimester attending our hospital during their antenatal visits and to know the fate of blighted ovum either if there is spontaneous expulsion of the sac or need of medical induction or surgical evacuation.Methods: This observational study was conducted at Obstetrics and Genecology Department, Women Health Hospital and Sahel Selim Hospital, Egypt from November 2015 to February 2018. All patients recruited in this study attended the antenatal care clinics for antenatal follow-up during their first-trimester of pregnancies.Results: All cases of the study were less than 14 weeks. The mean gestational age was 8.93±1.01 (7.0-11.0) weeks. In patients less than 20 years old, (73%) there is a significant increase in surgical treatment (dilatation & curettage) after failure of medical treatment, patients more than 40 years old (50.7%) there is a significant increase in medical treatment after success taking misoprostol so there is no need to a surgical treatment by (dilatation & curettage) in the majority of cases.Conclusions: The prevalence of blighted ovum was 15.6%. Also, the prevalence of blighted ovum was statistically significant increased with increase maternal age and also, we noticed that there was a statistically significant association between early pregnancy failure and a history of previous early pregnancy loss

ICP-OES Elemental Variation on Bottled Drinking Water

The work describes ICP-OES elemental variation (Be, B, Al, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Se, Mo, Ag, Cd, Sb, Ba,Sn, and Pb) in bottled drinking water.Special thanks for stuff in Faculty of Sciences, Al-azhar university