Beta-irradiation effects on the microstructure of LDPE samples have been investigated
using Positron Annihilation Lifetime Technique (PALT). These effects on the orthopositronium
(o-Ps) Lifetime t3, the free positron annihilation lifetime 2 t , the free-volume
hole size (Vh) and the free volume fraction (fh) were measured as functions of Beta
irradiation - dose up to a total dose of 30.28 kGy.
The results show that the values of t3, Vh and fh increase gradually with increasing Beta
dose up to a total dose of 1.289 kGy, and reach a maximum increment of 17.4%, 32.8% and
5.86%, respectively, while t2 reachs maximum increment of 211.9% at a total dose of 1.59
kGy. Above these doses, the values show nonlinear changes up to a maximum dose of
30.28 kGy.
The results are discussed in the view point that Beta - irradiation may induce degradation,
cross-linking and increasing of crystallinity in the amorphous regions of LDPE
In this study, the effect of intersecting ribs with inclined ribs on the heat transfer and flow characteristics of a high aspect ratio duct has been numerically investigated. The Relative roughness pitch (P/e) is 10 and the Reynolds number range from 35,700 to 72,800. ANSYS (Fluent-Workbench 18.0) software has been utilized to solve the Reynolds averaged Navier-Stokes (RANS) equations with the Standard k-ε turbulence model. Three ribbed models have been used in this study. Model 1 which is a just inclined ribs, Model 2 which has a single longitudinal rib at the center with inclined ribs and Model 3 which has two longitudinal ribs at the sides. The results showed that the heat transfer rate has been enhanced when the int
... Show MorePurpose This study was design to investigate of Purpose This study was design to investigate of P. aeruginosa, an example of Gram-negative bacteria, in seven primary and secondary schools of Baghdad city, and the effects of Ethanol and Dettol of P. aeruginosa biofilm. Design/methodology/approach Seventy swabs were collected from seven primary and secondary schools of Baghdad city, Iraq, during November -December 2022. Swabs were collected from classes desk, doors handles, students hands and water taps. Standard microbiological testing methods were used on the samples for isolation and identification. The ability of bacteria to form biofilm and the effects of Ethanol and Dettol on “preformed” biofilms was examined by microtiter plate wi
... Show MoreThe plant Conyza canadensis, which belongs to Asteraceae (Compositae) family and known as Canadian horseweed. It was used as traditional medicine in China, Pakistan, India, and Africa for the treatment of various diseases causing by bacteria, fungi, or viruses. The plant has antimicrobial, antioxidant, anticoagulant, anti-inflammatory, and anticancer pharmacological activity. This study provides the first phytochemical investigation of the plant in Iraq and is concerned with extraction, fractionation, isolation, and purification of some of the important phytochemicals detected in the plant-like phenolic acids, flavonoids, and alkaloids. Also, the literature survey has revealed that the plant has a substantial antimicrobial activity, so it w
... Show MoreAS Salman, SK Hameed…, Karbala Journal of Physical Education Sciences, 2020
Cadmium oxide (CdO) thin films were deposited using the sequencing ion layer adsorption and reaction (SILAR) method. In this study, the effect of the pH value of an aqueous solution of cadmium acetate at a concentration of 0.2 mol of the cadmium oxide film was determined. The solution source for the cadmium oxide film was cadmium ions and an aqueous ammonia solution. The CdO films were deposited on glass substrates at a temperature of 90 ℃. The cadmium oxide film thickness was determined by the weight difference method at pH values (7.2, 8.2). X-ray diffraction (XRD) and scanning electron microscopy (SEM) showed that the size of the crystals increased with the increase in the solution (pH). While the UV-visible spectra of the fil
... Show MoreGeomorphology is concerned with the topographic units that make up the Earth's surface. These take many forms, such as mountains and rivers, and include many dangers such as landslides, landslides and erosion. Many studies appeared in this field to analyze its effects and risks resulting from it, including urban studies, to determine the trends of optimal urban expansion and its geomorphological interactions. The results showed that the city of Kut originated and expanded near the course of the Tigris River and its branches, and it suffers from unbalanced urban expansion, due to the high rate of population growth, and overcrowding in housing units with the growth of urban land uses in it, which prompted the city to extend horizontally and v
... Show MoreThe aim of this study is to investigate the main causes of the family violence and its
social effects.
The study reveals that main factors causes of the violence are interaction between
multi-factors.
The study shows that the poverty, low educational level, house crowded, large family
size, all of these variables causes of the violence, and then causes of family disorganization
and juvenile delinquency.
The study contain of three sections:
First: Focused on the causes of the violence.
Second: The interaction between multi factors.
Third: Social effects of family violence.