Preferred Language
Articles
/
pBY3UogBVTCNdQwCs3aq
Characterizations and testing some mechanical properties of prepared PMMA-Lithium disilicate glass ceramic composite for denture base application
...Show More Authors

Denture bases are fabricated routinely using Poly(methyl methacrylate) (PMMA) acrylic resin. Yet, it is commonly known for its major drawbacks such as insufficient strength and ductility. The purpose of this study was to improve the performance of PMMA acrylic resin as a denture base material by reinforcement with surface treated lithium disilicate glass ceramic powder. The ceramic powder was prepared by grinding and sieving IPS e.max CAD MT blocks. Then, the powder was surface treated with an organosilane coupling agent (TMSPM) and added to PMMA in amount of 1%, 3%, 5% and 7% by weight. Characterizations of the powder was done by particle size analysis, XRD and FTIR. Transverse strength, Impact strength, Shore D hardness and surface roughness were tested for the prepared composites and neat PMMA. Particle size analysis showed that the average particle diameter was 1.46 µm. XRD confirmed the microstructure of IPS e.max CAD MT. FTIR showed the presence of TMSPM functional groups in the powder after treatment and there was a chemical interaction between the treated powder and the PMMA after the addition. One-way ANOVA and Tukey’s HSD test showed that there was a highly significant increase (P < 0.01) in transverse strength, impact strength and hardness with non-significant increase in roughness for 1% group. The mean values of 1% group were 67.3 MPa for transverse strength, 5.21 kJ/m2 for impact strength, 89.8 for Shore D hardness and 1.22 µm for surface roughness. While for control group, mean values were 59.3 MPa for transverse strength, 3.74 kJ/m2 for impact strength, 87.1 for Shore D hardness and 1.1 µm for surface roughness. However, with higher amounts of powder, there was a highly significant decrease in transverse strength and increase in roughness which was considered undesirable. In conclusion, reinforcing PMMA denture base material with 1% lithium disilicate glass ceramic powder may have the potential for enhancing the clinical performance of this material.

Scopus Clarivate Crossref
View Publication
Publication Date
Fri Dec 01 2017
Journal Name
International Communications In Heat And Mass Transfer
Synthesis, stability, and thermophysical properties of aqueous colloidal dispersions of multi-walled carbon nanotubes treated with beta-alanine
...Show More Authors

In the present study, multi-walled carbon nanotubes (MWCNTs) with outside diameters of< 8 nm and 20−30 nm were covalently functionalized with β-Alanine using a novel synthesis procedure. The functionalization process was proved successful using Raman spectroscopy, FTIR, and TEM. Utilizing the two-step method with ultrasonication, the MWCNTs treated with β-Alanine (Ala-MWCNTs) with weight concentrations of 0.025%, 0.05%, 0.075%, and 0.1% were dispersed in distilled water to prepare water-based nanofluids. The aqueous colloidal dispersions of pristine MWCNTs were unstable. While for Ala-MWCNTs and after> 50 days from preparation, higher colloidal stability was obtained up to relative concentration of 0.955 and 0.939 for the 0.075-wt% samp

... Show More
Crossref (25)
Crossref
Publication Date
Thu Apr 01 2021
Journal Name
Iraqi Journal Of Applied Physics
Effects of Solvent Properties on Absorption and Fluorescence Characteristics of Two Organic Dyes Used as Random Gain Media
...Show More Authors

In this work, the effects of solvent properties on the characteristics of absorption and fluorescence for two laser dyes was studied. Dyes used in this work include Coumarin 5400 and DCM, while the solvents include ethanol, methanol, acetone, propanol and chloroform. Coumarin 5400 dye shows sharp fluorescence peaks in the green band of visible region while the DCM dye shows relatively wide band within 590-630 nm. Therefore, the selection of any dye for random gain medium applications should be performed after determining the most appropriate solvent as the optimum fluorescence characteristics are obtained.

View Publication Preview PDF
Publication Date
Fri Dec 31 2010
Journal Name
Journal Of Legal Sciences
The moment of concluding the contract according to the United Nations Convention on Contracts for the International Sale of Goods (1980) (A comparative study with some Arab and foreign legislations)
...Show More Authors

There are two ways that the contract might be formed with (contracting between persons who are attended and contracting between absence persons).the need for determining the precise moment of the contract , is so clear because there is a specify period separate between the declaration of acceptance and the knowledge with it .and it is clear from the four theories known for jurisprudence (theory of the declaration of the acceptance, theory of exporting the acceptance , theory of the arrival of the acceptance , theory of the knowledge with the acceptance ) . It is difficult to promote one theory on another one if we look at each one and the justification of its supporters and what the opponents of each theory expose. Legal background and diff

... Show More
View Publication
Publication Date
Sun Jan 24 2016
Journal Name
Al-academy
Babylonian theater (Its history, models and properties) a historical comparative study: محمد صبري صالح
...Show More Authors

The building of the Babylonian theater is considered as one of the distinctive buildings where its foundations have remained steadfast in the face of geographical changes, social's erosion and groundwater that threatened almost all traces of Babylon despite the destruction of the outer structure of the building. The general directorate of antiques performed prospection for those foundations (the ground map), and then the building was completed by new bricks over the original scheme. It became clear when examining the building; its components and foundations, that the building is unique in comparison with the old buildings of the world throughout Iraq. There are similar buildings in other places like Jordan and North Africa such as

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Jun 30 2021
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
SYNTHESIS, CHARACTERIZATION, AND STUDY THE BIOLOGICAL ACTIVITY OF SOME SCHIFF'S BASES, AND 1,3 - OXAZEPINE COMPOUNDS DERIVED FROM SULFAMETHOXAZOLE DRUG: SYNTHESIS, CHARACTERIZATION, AND STUDY THE BIOLOGICAL ACTIVITY OF SOME SCHIFF'S BASES, AND 1,3 - OXAZEPINE COMPOUNDS DERIVED FROM SULFAMETHOXAZOLE DRUG
...Show More Authors

This study including synthesis of some new Schiff bases compounds [16] from the reaction of Sulfamethoxazole drug with some aromatic aldehydes in classical Schiff base method then treatment Schiff  bases with succinic anhydride to get oxazepines rings [7-11]These derivatives were characterized by melting point, FTIR, 1H NMR and mass spectra. Some of synthesized compounds were evaluated in vitro for their antibacterial activities against three kinds of pathogenic strains Staphylococcus aureus, Escherichia coli

... Show More
View Publication Preview PDF
Publication Date
Mon Jun 30 2008
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
The Relationships between the Physical and Chemical Properties of Narrow Fractions Distilled From Mixed Kirkuk and Sharki-Baghdad Crude Oils
...Show More Authors

Mixed Kirkuk and Sharki-Baghdad crude oils were distilled into narrow fractions. The range of these narrow fractions were 10oC, starting from IBP to 350oC. The total distillates from mixed Kirkuk and Sharki-Baghdad crude oils were 58.25 vol % and 44.65 vol %, respectively.The hydrocarbons compositions (paraffin, naphthene, aromatic) in light fractions starting from IBP to 250oC were determined by using PONA analysis method. The results show that the paraffin content decreases with increasing mid percent boiling point of the fraction, while the naphthene, and aromatic increase with the increase of mid percent boiling point of mixed Kirkuk and Sharki-Baghdad crude oils. Three groups of empirical equations were developed for the prediction

... Show More
View Publication Preview PDF
Publication Date
Thu Dec 01 2011
Journal Name
Journal Of Economics And Administrative Sciences
application of business managment in the field of football with studuy of the case of spanish club (Real Madrid) و (Barcelona
...Show More Authors

Football has progressed from being a ritual and a celebration to become an amateur sport, a professional sport, and now, increasingly, a commercial sport. In the analysis of football business model, the systemic approach should be adopted. If sport is regarded as one of the business sectors, then the application of business system methodology can be fully justified. The interest to create strong football business system calls for the search of the ways of popularizing football business model and boosting the economic potential of its participants. In the research literature tend to ignore the business processes within the sports business. Besides, the systemic approach in football business is usually limited to p

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Nov 24 2024
Journal Name
Polymer-plastics Technology And Materials
Li <sub>2</sub> CO <sub>3</sub> as a Modifier for PVA/PVP/PEG Blend Polymer Electrolytes: Effects on Structural Integrity, Electrical Performance, Thermal Behavior and Optical Properties
...Show More Authors

View Publication
Scopus (7)
Crossref (6)
Scopus Clarivate Crossref
Publication Date
Wed Apr 10 2019
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
QUALITY SYSTEMS.POSSIBILITY OF IMPLEMENTING IN SOME LOCAL FOOD ESTABLISHMENTS: QUALITY SYSTEMS.POSSIBILITY OF IMPLEMENTING IN SOME LOCAL FOOD ESTABLISHMENTS
...Show More Authors

In order to have an idea about what happens in Iraqi food establishments in relation to implement quality management system ISO 9001, this study was performed to show the actual situation of Iraqi food establishments concerning quality management system (ISO 9001:2015), reasons of implementing, factors that hinder implementing and problems faced high administration for getting establishments certification ISO 9001:2015. The study demonstrated from the questionnaire some difficulties to implement ISO 9001 for both of establishments that implemented the quality system or which in implementing of this international standard. The most important problems during implementing were business culture and costs and the most important proble

... Show More
View Publication Preview PDF
Publication Date
Mon Apr 04 2016
Journal Name
Iraqi Journal Of Physics
Thickness and gamma-ray effect on physical properties of CdO thin films grown by pulsed laser deposition
...Show More Authors

Polycrystalline Cadmium Oxide (CdO) thin films were prepared using pulsed laser deposition onto glass substrates at room temperature with different thicknesses of (300, 350 and 400)nm, these films were irradiated with cesium-137(Cs-137) radiation. The thickness and irradiation effects on structural and optical properties were studied. It is observed by XRD results that films are polycrystalline before and after irradiation, with cubic structure and show preferential growth along (111) and (200) directions. The crystallite sizes increases with increasing of thickness, and decreases with gamma radiation, which are found to be within the range (23.84-4.52) nm and (41.44-4.974)nm before and after irradiation for thickness 350nm and 4

... Show More