Numerical simulations were carried out to evaluate the effects of different aberrations modes on the performance of optical system, when observing and imaging the solar surface. Karhunen-Loeve aberrations modes were simulated as a wave front error in the aperture function of the optical system. To identify and apply the appropriate rectification that removes or reduces various types of aberration, their attribute must be firstly determined and quantitatively described. Wave aberration function is well suitable for this purpose because it fully characterizes the progressive effect of the optical system on the wave front passing through the aperture. The Karhunen-Loeve polynomials for circular aperture were used to

    As part of our research on efficiency improvement of PERC (Passivated Emitter Rear Solar Cell), achieving very low reflectivity values of solar cell surface is a must. One of the most advance technologies to do so is the use of advanced texturing for the front surface of the cells. This texture, also known as Black Silicon, consists of peaks and valleys of nano metric dimensions and capable of dramatically reducing the reflectance of the front surface. A reflectance around 5%  was reached ,using simulation, when using a Black-Silicon texturing with height of 50nm with peak rounding of 5nm. Even though this texturing may affect other parameters such as series resistance or surface recombination, as a starting point

In this research, we investigate and evaluate the efficiency of a hetero junction N749-  device based on a simple donor-acceptor model for electron transfer. Electron transfer from a photo-excited N749 sensitized into a wide-band gap  is the basic charge separation in dye-sensitized solar cells, or "DSSCs". Due to the understanding of the current of the DSSCs functioning mechanism, the energy levels of the hetero junction N749-  device surrounded by DCM solvent as polar media must be continuum levels. The current-voltage (J-V) characteristics of the N749- device are calculated in two concentrations at room temperature (T=300 k) and 100   irradiation. The fill factor and efficiency of the device are found to be 0.134 and 6.990 for con

Solar cells thin films were prepared using polyvinyl alcohol (PVA) as a thin film, with extract of natural pigment from local flower. A concentration of 0.1g/ml of polyvinyl alcohol solution in water was prepared for four samples, with various concentrations of plant pigment (0, 15, 25 and 50) % added to each of the four solutions separately for preparing (PVA with low concentrated dye , PVA with medium concentrated dye and PVA with high concentrated dye ) thin films respectively . Ultraviolet absorption regions were obtained by computerized UV-Visible (CECIL 2700). Optical properties including (absorbance, reflectance, absorption coefficient, energy gap and dielectric constant) via UV- Vis were tested, too.  Fourier transform infra

The aim of this article is to solve the Volterra-Fredholm integro-differential equations of fractional order numerically by using the shifted Jacobi polynomial collocation method. The Jacobi polynomial and collocation method properties are presented. This technique is used to convert the problem into the solution of linear algebraic equations. The fractional derivatives are considered in the Caputo sense. Numerical examples are given to show the accuracy and reliability of the proposed technique.

The issue of the prisoners' rights and the way of dealing with them is not just a minor or
primary issue according to the contemporary attitudes to deal with criminals, but it is a fatal
issue that goes with the development of life and comprehension of human rights. As the
criminal is considered as a human-being who can be reformed and qualified, according to the
aims of the contemporary social service the prisoner is regarded as an idle human source who
can be reformed, treated and qualified so as to make him participate to improve his family and
society in the end.
This study aims at reconstructing the prisons bases when applying the laws of the lowest
level of treatment through the research of oppositions, atti

     In this work, the annual behavior and cross-correlation between three different solar-ionospheric indices were evaluated: Smoothed Sunspot Number (SSN), Ionospheric T-Index (T-index), and Solar Flux (F10.7 cm) index during solar cycles 23 and 24. The annual behavior for the three tested indices of the maximum and minimum years of the two solar cycles was studied. The correlative conducts between the studied indices were evaluated for the studied periods (1996-2008) and (2008-2019) of the 23rd and 24th solar cycles. The annual correlation between the studied indices was represented by the linear regression equation. The suggested mutual correlation equation gave a good agreement with the observed annual average values of the test

This work is an experimental investigation for single basin-single slope solar still coupled with an evacuated tube solar collector. The work is carried out under the climatic conditions of Baghdad city (33.2456º North and East latitude, 44.3337º longitude) through certain days of the months of the year 2019 to study the impact of using evacuated tube solar collector on the daily productivity and efficiency under the outdoors climatic conditions. It was found that using the evacuated tube solar collector increase daily productivity from 2.175 kg/  to 2.95 kg/ for 9 hours (35.63 %) for clear days, also an enhancement about 10.97 % in daily efficiency.

Strong acids were determined via the precipitation reaction of loaded copper (II) ion on strong cation exchange resin which in turn reacts with potassium hyxacyano ferrate (II). The attenuation effect of formed precipitate Cu2 [Fe (CN) 6] on (0 -180o) incident LED light was measurement via homemade AYAH 5SX4-ST-5D solar CFI analyser. Optimum parameters were 0.005M.L-1 [Fe(CN)6]-4 , flow rate of 2.4 mL.min-1 , sample volume 204 μL , sample purge time of 64 seconds was chosen, and 1.6 V for light intensity. A liner calibration graph of 0.005 -0.2 M.L-1 were obtains for HCl, HNO3, HCLO4 and H2SO4, with a linearity (r2 %) 96 -97 % and L.O.D based on gradual dilution of lowest concentration in calibration graph was 37.19 μg for HCl, 64.273