Preferred Language
Articles
/
alkej-94
Studying the Mechanical Properties of Denture Base Materials Fabricated from Polymer Composite Materials
...Show More Authors

In this research, the effect of adding two different types of reinforcing particles was investigated, which included: nano-zirconia (nano-ZrO2) particles and micro-lignin particles that were added with different volume fractions of 0.5%, 1%, 1.5% and 2% on the mechanical properties of polymer composite materials. They were prepared in this research, as a complete prosthesis and partial denture base materials was prepared, by using cold cure poly methyl methacrylate (PMMA) resin matrix. The composite specimens in this research consist of two groups according to the types of reinforced particles, were prepared by using casting methods, type (Hand Lay-Up) method. The first group consists of PMMA resin reinforced by (nano-ZrO2) particles, while the second group consists of PMMA resin reinforced by (micro-lignin) particles.

The mechanical tests performed in this research includedtensile test, compression test, impact test and hardness test. The results of this study showed that the values of tensile modulus of elasticity, compressive strength and hardness properties increased with increasing the volume fraction of these particles in PMMA composite materials. While, the values of tensile strength, elongation and impact strength properties decreased. Also, the addition of (nano-ZrO2) particles showed greater effect than that of (micro-lignin) particles in some properties of PMMA composite materials for prosthesis denture base materials specimens, while they have lower effect for the other properties.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Wed Jul 01 2020
Journal Name
Journal Of Engineering
Improvement the Mechanical Characteristics of Alloy Steel DIN 41Cr4 by Shot Peening
...Show More Authors

The effects of shot peening treatment (SPT) were studied at (10,20, and 30) minutes on the rotating bending fatigue behavior and the behavior of the alloy steel DIN 41Cr4 vibrations. The hardness test, tensile test, constant amplitude fatigue tests, and the vibration measurements were performed on samples with and without cracks at room temperature (RT), also, the fracture surface was examined and analyzed by a Scanning Electron Microscope (SEM). The results of the investigations, for example, Stress to Number of cycles to failure (S-N) curves, fatigue strength improvement factor of 5% to 10%, the decreasing percentage of maximum Fast Fourier Transform (FFT) acceleration of the shot-peened condition were compared to untr

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Sun Feb 01 2015
Journal Name
Journal Of Engineering
Vibration Analysis of a Composite Plate with Delamination
...Show More Authors

The use of composite materials has vastly increased in recent years. Great interest is therefore developed in the damage detection of composites using non- destructive test methods. Several approaches have been applied to obtain information about the existence and location of the faults. This paper used the vibration response of a composite plate to detect and localize delamination defect based on the modal analysis. Experiments are conducted to validate the developed model. A two-dimensional finite element model for multi-layered composites with internal delamination is established. FEM program are built for plates under different boundary conditions. Natural frequencies and modal displacements of the intact and damaged

... Show More
View Publication Preview PDF
Publication Date
Mon Aug 01 2022
Journal Name
Journal Of Engineering
Mechanical Integrity of Printed Circuit Heat Exchanger
...Show More Authors

The printed circuit heat exchanger is a plate type heat exchanger with a high performance and compact size. Heat exchangers such as this need a unique form of bonding and other techniques to be used in their construction. In this study, the process of joining plates, diffusion bonding, was performed and studied. A special furnace was manufactured for bonding purposes. The bonding process of copper metal was carried out under specific conditions of a high temperature up to 700 oC, high pressure of 3.45 MPa, and in an inert environment (Argon gas) to make tensile samples. The tensile samples are cylindrical shapes containing groves representing the flow channels in the printed circuit heat exchanger and checking their tensile st

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Sep 01 2014
Journal Name
Al-khwarizmi Engineering Journal
Production of Bioethanol from Waste Potatoes
...Show More Authors

In this research, production of ethanol from waste potatoes fermentation was studied using Saccharmyses cerevisiae. Potato Flour was prepared from potato tubers after cooking and drying at 85°C. Homogenous slurry of potato flour was prepared in water at solid liquid ratio 1:10. Liquefaction of potato flour slurry with α-amylase at 80°C for 40 min followed by saccharification with glucoamylase at 65°C for 2 hr .Fermentation of hydrolysate with Saccharomyces cerevisiae at 35°C for two days resulted in production of 33 g/l ethanol.

      The parameters studied were; temperature, time of fermentation and pH. It was found that Saccharification process is affected by enzyme Amylo 300 conc

... Show More
View Publication Preview PDF
Publication Date
Sun Dec 01 2024
Journal Name
Energy Storage
Comprehensive Study of <scp>PAN</scp>‐<scp>NaBF<sub>4</sub></scp> Solid Polymer Electrolytes: Insights Into Optical, Structural, Thermal, Electrical, and Electrochemical Properties for Sodium‐Ion Batteries
...Show More Authors
ABSTRACT<p>This research explores the use of solid polymer electrolytes (SPEs) as a conductive medium for sodium ions in sodium‐ion batteries, presenting a possible alternative to traditional lithium‐ion battery technology. The researchers prepare SPEs with varying molecular weight ratios of polyacrylonitrile (PAN) and sodium tetrafluoroborate (NaBF<sub>4</sub>) using a solution casting method with dimethyl formamide as the solvent. Through optical absorbance measurements, we identified the PAN:NaBF<sub>4</sub> (80:20) SPE composition as having the lowest energy band gap value (4.48 eV). This composition also exhibits high thermal stability based on thermogravimetric analysis results. </p> ... Show More
View Publication
Scopus (7)
Crossref (7)
Scopus Clarivate Crossref
Publication Date
Sun Jun 01 2014
Journal Name
Baghdad Science Journal
Study of Some Physical and Chemical Properties of Staphylolysin Enzyme purified from Pseudomonas aeruginosa
...Show More Authors

Some of the characters of the Staphylolysin A and D enzymes purified from Pseudomonas aeruginosa P16 and P5 respectively were studied, the molecular weights of Staphylolysin A and D were 20.417 kilo dalton and 23.988 kilo Dalton respectively by SDS- polyacryl amide gel electrophoresis. The optimum pH for staphylolysin A activity was found to be 8 which gives higher activity reaches 150 unit/ml, and for enzyme stability was 7.5-8.5 in which the enzyme nearly retained its full activity, while it was 9.5 for staphylolysin D that gives higher activity of 16 unit/ml,and 8.5-9.5 for enzyme stability in which the enzyme nearly retained its full activity, Maximum activity of two enzymes was obtained at 40C in which the specific activity for st

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Jun 01 2022
Journal Name
Baghdad Science Journal
Investigating the Effect of Drugs of Chloramphenicol and Gentamicin on Acanthamoeba genotype T3 Causing keratitis Isolated from Environmental samples in vitro
...Show More Authors

This study is an investigation of the drugs effect on some pathogenic Acanthamoeba isolated from Iraqi waters, where the problem of environmental adaptation that characterizes this organism in addition to being a reservoir for many pathogenic microorganisms that take shelter in it to escape disinfectants and medicines is sometimes difficult to treat it with traditional treatments.  Twenty water samples were collected from different water regions in Iraq, namely the Dokan Lake, Tigris River, Euphrates River and Najaf Sea, 5 samples from each source.  Acanthamoeba was isolated from water samples on NNA and PYG media, using an inverted microscope with an electron microscope to determine their phenotypic features. PCR and

... Show More
View Publication Preview PDF
Scopus Clarivate Crossref
Publication Date
Wed Jan 21 2026
Journal Name
Al–bahith Al–a'alami
THE ROLE OF WESTERN LEGISLATIONS AND LAWS IN PROTECTING CHILDREN FROM ADVERTISEMENT
...Show More Authors

This study aims to identify the most important legislatures and legal frameworks pertaining to advertisement for children. It focuses on the western approach, which is characterized by the variety of its perspectives in presenting issues and in identifying problems. However, if studies show that there is a certain awareness about the advertisement impact on children, it is obvious that most of legislatures reject the laws restricting the broadcast advertising spots intended for children under 12 years of age, with the exception of the Swedish and the Canadian province of Quebec experiences, which opted for total ban on advertising spots broadcast messages targeting children.

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Jan 03 2016
Journal Name
Journal Of Educational And Psychological Researches
Professional competencies and teaching university professor from the point of view of students
...Show More Authors

Targeted Search:

-scale preparation of teaching and professional competencies required for university professor from the perspective of students from different disciplines.

-scale application prepared by the researcher for the students to see how their preference for these competencies to their professors.

-limited Search: Find determined to present the following

-students of both sexes in the University of Baghdad.

2013 -      2012

... Show More
View Publication Preview PDF
Publication Date
Sun Dec 31 2023
Journal Name
College Of Islamic Sciences
Imam Al-Mubarakpuri's Jurisprudential Choices (d.1353 AH) in the Borders from his book "Tuhfat Al-Ahwadi" with the explanation of "Jami' Al-Tirmidhi / a comparative jurisprudential study
...Show More Authors

Praise be to God, Lord of the Worlds, and prayers and peace be upon the Master of Messengers and his family and companions.

The study of the jurisprudential opinions of scholars, their choices, or their weightings, sheds light on the approach they followed in their choices, and reveals the originality of the scholar or his influence on those who preceded him from among the scholars.

And the commentators of the noble hadith of the Prophet have their important contributions in this aspect, as they undertake the task of explaining the noble hadith, the second source of legislation

Contemporary commentators have their share in the service of the honorable hadith, and the statement of their choices and preferences, and am

... Show More
View Publication Preview PDF