Preferred Language
Articles
/
jbcd-294
Evaluation the effect of nano-fillers (TiO2, AL2O3, SiO2) addition on glass transition temperature, E-Moudulus and coefficient of thermal expansion of acrylic denture base material
...Show More Authors

Background: The PMMA polymer denture base materials are low in thermal and strength properties. The aim of the study was to investigate the change in glass transition temperature, E-Moudulus and coefficient of thermal expansion of acrylic denture base material by addition of Al2O3, TiO2 and SiO2nano-fillers in 5% by weight. Materials and methods: The type of polymerization is free radical bulk polymerization. one hundred twenty (120) specimens were prepared , the specimens were divided into four groups according to the material had been added (one control and three for Al2O3, TiO2 and SiO2nanocomposite) each group was subdivided in to three groups according to the test had been done on it, the degree of transition (Tg) was measured by The differential scanning calorimeter (DSC), E-Modulus and coefficient of thermal expansion and contraction was measured by Thermo Mechanical Analyzer (TMA) .Each sample was tested at different temperatures (30,40,50,60,70C°). Results: Highly significant decrease in coefficient thermal expansion and contraction and in E-Modulus occurred in acrylic incorporated with Al2O3, TiO2 and SiO2 nano-fillers in 5% by weight when compared to control group. For glass transition temperature a significant increase had occurred with the addition of nanofillers at 5% when compared to control group. Conclusion: The results showed that the polymer nanocomposites possess material properties different from that of unmodified PMMA, nanocomposite has thermal and mechanical stability more than heat neat PMMA.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Wed Dec 18 2019
Journal Name
Baghdad Science Journal
Effect of Refractive Index on Photon Natural Mass and Wavelength
...Show More Authors

In this article it is proved experimentally that the photon is a particle that has mass and constant wavelength by explaining the effect of refractive index on the wavelength and the natural mass of photon. It is very difficult to measure the mass of photon, a simple and easy process was proposed in this paper to calculate the mass length of photon in vacuum (Y) and in medium (Y*), by measuring the length of laser beam in air (Lair) and in medium (Lmed). A new method was postulated to calculate refractive index by using these relations (n = Y*/Y), and (n = Lmed / Lair) which supposed a new theory of light.

View Publication Preview PDF
Scopus Clarivate Crossref
Publication Date
Tue May 01 2018
Journal Name
Journal Of Physics: Conference Series
Doping And Annealing Effect On Evaporation Of ZnO Thin Films
...Show More Authors

View Publication Preview PDF
Scopus (2)
Scopus Clarivate Crossref
Publication Date
Sun Dec 05 2010
Journal Name
Baghdad Science Journal
Effect of vincristine and vinblastine on mice spermatozoa in vitro
...Show More Authors

The aim of this project was to study the in vitro effect of antineoplastic drugs (vincristine and vinblastine) on mice spermatozoa. Eighteen adult (age 8-9 weeks) male mice were divided into three groups equally. The animals in each group were slain by cervical dislocation, the testes were removed and two tails of epididymides isolated. Spermatozoa were obtained from the two tails of epididymides by mincing in 500 µl TCM-199.The first group non-treated (unadded) as a control group, second group added 10 µg/ml of vincristine to TCM-199 and the third group added 10 µg/ml of vinblastine to TCM-199. After 10 minutes from added of vincristine and vinblastin measured the following test: spermatozoa activity, percentage dead spermatozoa and mor

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Wed Mar 15 2023
Journal Name
Bionatura
Effect of traditional and automated sorting on some tomato's properties
...Show More Authors

This study was conducted in a laboratory experiment at the University of Baghdad, College of Science, computing Department, 5 km from the center of Baghdad city, in 2021 to evaluate the sorting method for the tomato crop. The experiments were conducted in a factorial experiment under a complete randomized design with three replications and using SAS analysis, artificial neural network, image processing, the study of external characteristics, and physical features; fruit surface area and fruit circumference were 1334.46 cm2,57.53 cm2 and free diseases. The error value was less than zero, while training with outputs recorded the highest value and which was 5. The neural network's performance between the input and the mean square of th

... Show More
View Publication
Scopus (2)
Crossref (1)
Scopus Crossref
Publication Date
Sat Jan 01 2022
Journal Name
Ssrn Electronic Journal
Developing a Predictive Model and Multi-Objective Optimization of a Photovoltaic/Thermal System Based on Energy and Exergy Analysis Using Response Surface Methodology
...Show More Authors

View Publication
Crossref (4)
Crossref
Publication Date
Sun Mar 03 2019
Journal Name
Diyala Journal For Pure Scince
Study influence of thickness and electrode mater on some electrical properties for ZnSe thin films prepared by thermal evaporation in vacuum
...Show More Authors

Thin films of Zinc Selenide ZnSe have been prepared by using thermal evaporation in vacuum technique (10-5Torr) with thickness (1000, 2700, 4000) A0 and change electrode material and deposited on glass substrates with temperature (373K) and study some electrical properties at this temperature . The graphs shows linear relation between current and voltage and the results have shown increases in the value of current and electrical conductivity with increase thickness and change electrode material from Aluminum to Copper

Publication Date
Sun Mar 06 2011
Journal Name
Baghdad Science Journal
Studying of the optical properties of poly (vinyl alcohol) films using Aluminum sulphate as additive by measuring allowed direct transition energy gap
...Show More Authors

The change in the optical band gap and optical activation energy have been investigated for pure Poly (vinyl alcohol)and Poly (vinyl alcohol) doped with Aluminum sulphate to proper films from their optical absorption spectra. The absorption spectra were measured in the wave range from (200-700) nm at temperature range (25-140) 0C. The optical band gap (Eg) for allowed direct transition decrease with increase the concentration of Aluminum sulphate. The optical activation energy for allowed direct transition band gap was evaluated using Urbach- edges method. It was found that ?E increases with increasing the concentration of Al2 (SO4)3 and decreases when temperature increases.

View Publication Preview PDF
Crossref
Publication Date
Tue Feb 01 2022
Journal Name
International Journal Of Nanoscience
Study of the Transition State of SnO<sub>2</sub> Cluster with NO<sub>2</sub> Gas Molecule via Density Functional Theory
...Show More Authors

Density functional theory (DFT) with B3LYP level and 6-311G[Formula: see text] basis sets for light atoms like N and O and SDD basis sets for heavy atoms like Sn is used to examine the interaction of tin dioxide nanocrystals with nitrogen dioxide as a function of temperature from 273[Formula: see text]K to 373[Formula: see text]K through a Gaussian 09W software program. Gibbs free energy, enthalpy, and entropy of activation and reaction are calculated. The situation of transition of SnO2 clusters toward nitrogen dioxide is investigated. According to the findings, the activation energy of SnO2 clusters with nitrogen dioxide increases as the temperature rises (in negative value). Gauss view 0

... Show More
View Publication
Scopus (1)
Scopus Clarivate Crossref
Publication Date
Sat Nov 29 2025
Journal Name
Journal Of Baghdad College Of Dentistry
An In Vitro Evaluation of the Effectiveness of Gotu Kola (Centella asiatica) on Inhibiting the Growth of Selected Microorganismsin Human Saliva
...Show More Authors

Background: Gotu Kola (Centella asiatica) has been used as a traditional medicine for many years to cure different kinds of diseases. Studies have been reported that Gotu Kola extracts might be used as a cure for oral diseases such as periodontal disease. In the present study, Gotu Kola leaves extracted with water will be used to evaluate its effect on some microorganisms living in the human saliva using minimum inhibitory concentration (MIC) method. Material and Method:Gotu Kola fresh leaves extract have been used with water as a solvent, a rotary evaporator was used to separate the solvent from the extract. The following microorganisms: Streptococci, Lactobacilli, and Staphylococcus aureus have been isolated fromthe Saliva of ten voluntee

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Dec 24 2023
Journal Name
Journal Of The College Of Basic Education
Structural, Characterization, Biological and Studying the Enzyme Activity of some transition metal complexes with 4- )(2- hydroxy phenyl imino) methyl) -2, 6-dimethoxy phenol
...Show More Authors

A new Schiff bases ligand 4- ((2-hyolroxy phenylimino) methyl) -2, 6-dimethoxyphenol  derived from condensation of 2- amino phenol with 4-hydroxy -3, 5-dimethoxy benzaldehyde have been synthesized and characterized by  spectroscopy,  spectra, Mass spectrum and elemental microanalysis (C.H.N). Metal Complexes with ions have been also synthesized and characterized spectroscopic methods  spectroscopy, flame atomic absorption, molar conductivity measurements and magnetic susceptibility. These studies indicate that the moler ratio  for the complexes. The complexes  showed characteristics octahedral geometry with the (O,N) ligand coordinated in bidentate mode while with  showed square planer. The enzyme activity of the ligand and i

... Show More
View Publication
Crossref