2023-01

Science Journal of the University of Zakho (Issue : 2023) (Volume : 11)

The Successive Ionic Layer Adsorption and Reduction (SILAR) method was utilized to produce nanostructured silver thin films on a glass substrate. Ag nanoparticles were grown using SILAR parameters such as silver nitrate (AgNO3), reduction time, reduction agent in an aqueous solution of hydrazine hydrate with various concentrations, and growth cycles. In this study, X-ray diffraction (XRD), scanning electron microscopy (SEM), and UV-visible-NIR absorption spectroscopy techniques were used to assess the produced silver thin film nanostructure. The size and spreading of the formed silver nanoparticles are observed to grow with the reducing agent and eventually saturate for constant growth cycles. As a result, the size and the distribution of the produced Ag nanoparticles grow uniformly. Higher growth cycles, however, caused Ag nanoparticles to lose their homogeneity and change into gravel-shaped particles. Therefore, silver nanoparticles that have been produced with the ideal SILAR conditions can be employed as an extremely sensitive, repeatable substrate with an exceptionally efficient factor. Moreover, the Effect of the concentration of HyH on the properties of SILAR-grown silver thin films has been extensively studied.

2022-09

Passer Journal (Issue : 2) (Volume : 4)

Silver (Ag) thin-film nanostructures are prepared on the glass surface through a dependable method called spin coating. Silver nitrate (AgNO3) has been utilized as precursors, proceeded by the thermal reduction in the H2 atmosphere, and some of the chemical reductions such as sodium borohydride (NaBH4) solution, and hydrazine hydrate solution (N2H4). The effects of several reductants have been discussed. The structure, morphology, and absorbance spectra of the deposited silver thin films have been characterized and measured by using the following techniques X-ray diffraction (XRD), Scanning electron microscope (SEM), as well as UV-visible- NIR absorption spectroscopy, to study more about how the reduction procedure affects the formation of silver nanoparticles. As a result, thermal reduction in the H2 atmosphere is more effective than the chemical reduction in aqueous sodium borohydride and hydrazine hydrate solution for growing consistently sized dispersed silver nanoparticles.

2022-08

Passer Journal (Issue : 2) (Volume : 4)

Supernova remnants (SNRs) are remarkable astronomical objects which are a diffuse, an expanding nebula of gas that is a direct result of a star's explosive death, resulting in a supernova explosion. SNRs play a vital role in the scattering of tough elements which are made in the supernova explosion into the interstellar medium and provide much amount of energy that heats the ISM, as well as its responsible for enormous differences in physical process and properties. In the present work, we study the physical properties, performance, and behavior of dynamical growth of several types (SNR Ia and II) specifically after an explosion of a supernova, and explore how the density of the interstellar environment affects the physical properties and eternity of each SNRs. To achieve such goals, we have utilized the method known as Counting Pixels Method, which has been applied to the SNRs images as well as a new pattern that has been suggested to calculate some of the physical properties such as the expansion velocity and the radius of the chosen remnants, which are based on the age of SNRs and the density of the surrounding medium. The outcomes of the study have depicted that each chosen SNRs type Ia and II likewise in performance and behavior after a long period of explosion Nevertheless, they are displaced either upwards or downwards based on the interstellar density. However, we noted that SNRs are exploded in the lower density environment and expanded without restriction to make a regular shape. We have concluded that further study is required particularly on the physical properties of SNRs when inserted into the radiative phase.

2016-09

International Journal of Astronomy (Issue : 2016) (Volume : 5)

Craters occur when an objects like Asteroids, Comets and Meteorites hits onto the surfaces of Moon and Planets and their impact has became a major geological process. The objective of the project is to investigate how the size of a Meteorite and Asteroid on the Moon and Planets is related to the size of impact crater. We started with a two round stone of different mass and size covered slightly with a layer of a viscous mud fluid as a fragmentation were dropped at variable height onto the flour. However, we have used a layer of sprinkles as a mineral diversity of the surface impacted. We have measured the diameter, depth and the Ejecta distance of the crater each time, there were three trails for each stone drop height. The results shows that, the crater diameter and the crater depth increased as the height and mass of the ball drop increased in addition of increasing Ejecta distance.

2015-09

Advances in Materials Physics and Chemistry (Issue : 2015) (Volume : 5)

The Dye Sensitized Solar Cell (DSSC) plays an important role because of low material cost, ease of production and high conversion efficiency as compared to other thin-film solar cell technologies. The main objective is to create and find the best configuration of the solar cell based on materials that are inexpensive and highly efficient in solar energy conversion and subsequently test the efficiency of dye sensitized titanium dioxide solar cell. We begin the process with two glass plates coated with Fluorine tin oxide (FTO). Titanium dioxide is applied to the conductive side of one plate and the other plate is coated with graphite. A dye is adsorbed on to the TiO2 layer and then the plates are sandwiched together. A drop of iodide electrolyte is then added between the plates. The tests carried out indoors under a lamp emitting all wavelengths in the visible spectrum were not found to provide consistent data due to substantial heating of the cell. The outdoor tests carried out in natural sunlight exhibited steady voltage at much higher level. Future research will involve the incorporation of quantum dots instead of the organic dye as a sensitizer. Quantum dots have the advantages of providing tunable band gaps and the ability to absorb specific wavelength.

2015-04

Advances in Materials Physics and Chemistry (Issue : 2015) (Volume : 5)

In-doped (Se0.7Te0.3) thin films (In: 0, 0.05, and 0.08wt%) with thickness of (150 ± 25 nm) have been deposited on glass substrates by chemical vapor deposition by using selenium, tellurium and indium whose purity is (99.99%) compound alloy. The electrical and optical properties of the thin films were analyzed. The effects of In-doping concentration on the thermoelectric properties of the thin films were investigated by room-temperature measurement of the See beck coefficient and electrical resistivity. The thermoelectric power factor shows the best result at 0.05wt% in doping. The See beck coefficients are positive with increasing in doping concentration from 0 to 0.08wt%. And the thin films show p-type conduction. For optical properties, the transmission of all samples was approximated to 90%.

2015-03

Materials Sciences and Applications (Issue : 2015) (Volume : 6)

The present work measured the bulk etch rate (VB) of solid state nuclear track detector by taking the diameter time measurement of alpha particle in CR-39 detector. The values of the track diame- ter have been found by using TRACK-TEST program from Yu et al. function and Brun et al. function with different energies of alpha particles. The results showed that the time-diameter (t-d) method gave good results of the bulk etch rate (VB) and these values were (1.705 and 1.72) µm・hr−1. They showed good agreement with the values measured by using the other methods, and it was a simple method because it required getting diameters of the tracks in the detector with the etching time.

2015-02

Materials Sciences and Applications (Issue : 2015) (Volume : 6)

The aim of this paper is to determine the maximum values of the track length (Lmax) of alpha particles in Nuclear Track Detector (type CR-39) using a new method by taking the relation between the etching time and the diameter square of alpha particle with different energies at constant bulk etch rate VB (1.45 µm/hr) by using TRACK_TEST program from Brun et al. function and Yu et al. function. Using the new equation, the maximum values of the track lengths of alpha particles measured in CR-39 detector have been found to be in a good agreement with the values measured by using Brun et al. function and Yu et al. function in TRACK_TEST program.