Preferred Language
Articles
/
jbcd-1854
Marginal Discrepancy and Fracture Resistance of CAD/CAM Ceramill Sintron Metal Copings with Different Porcelain Materials
...Show More Authors

Background: This study was performed to compare the marginal fit changes and facture resistance of metal ceramic crowns constructed from Ceramill Sintron metal coping veneered with three different porcelain veneering materials (Vita Master Koromikos VMK, Willi Geller Creation CC and GC initial MC), also to evaluate the influence of thermocycling on load at fracture. Materials and Methods: Master brass die was scanned ,then metal coping was designed and milled from Ceramill Sintron blank to get 60 metal copings, then divided randomly into three groups(20 sample), then veneered with porcelain: VITA, Creation or GC. The marginal gaps were measured before and after porcelain veneering then marginal fit changes was calculated. Fracture resistance test was done by Instron®, the master die was duplicated to sixty analogs then each analog was fixed into acrylic base. After that each crown was cemented onto the corresponding die analog. Ten samples of each group were subjected to compressive loading to fracture and other ten subjected to thermocycling followed by compressive loading to fracture. Result and Conclusion: The result of marginal fit changes showed that GC group had the lowest marginal gap follow by VITA and Creation. While VITA group showed the highest fracture resistance follows by GC then Creation. Thermocycling process did not significantly reduce the load at fracture for all groups.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Mon Oct 01 2018
Journal Name
Journal Of Engineering
The Response of Some Properties of (Al-Si-Mg) Alloy to Nano-Ceramic Materials’ Addition
...Show More Authors

Al-Si alloys which are widely used in engineering applications due to their outstanding properties can be modified for more enhancements in their properties. Current work investigated the ability of these alloys to be modified by casting them through the addition of nanoparticles. So, Multi-wall carbon nanotubes (CNT) and titanium carbide ceramic particles (TIC) with size of (20 nm) were added with different amounts started from (0.5 up to 3%) weight  to cast alloy A356 that was considered to be the base metal matrix, then stirred with different speeds of (270, 800, 1500, 2150) rpm at 520 °C for one minute. The results showed change in microstructure’ shape of the casted alloys from the dendritic to spherical gra

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Sep 19 2021
Journal Name
Journal Of Petroleum Research And Studies
Enhancing the Rheological Properties of Water-Based Drilling Fluid by Utilizing of Environmentally-Friendly Materials
...Show More Authors

Recently, many materials have shown that they can be used as alternatives to chemicals materials in order to be used to improve the properties of drilling fluids. Some of these materials are banana peels and corn cobs which both are considered environmentally- friendly materials. The results of the X-ray diffraction examination have proved that the main components of these materials are cellulose and hemicellulose, which contribute greatly to the increasing of the effectiveness of these two materials. Due to their distinct composition, these two materials have improved the rheological properties (plastic viscosity and yield point) and reduced the filtration of the drilling fluids to a large extent. The addition rates used for each o

... Show More
View Publication
Crossref (6)
Crossref
Publication Date
Tue Jan 18 2022
Journal Name
Materials Science Forum
The Effect of Tidal Energies on the Materials Properties of the Soil at Southern Mesopotamia
...Show More Authors

The materials of soil were affected by multi reasons; such as human activities, floods, tidal waves, ... etc. The change of the soil contents could be measured through different indexes; such as electric conductivities, salinity, concentration of the heavy elements, and concentration of essential elements ... etc. The land cover is affected by natural influences, like tidal energy, which plays a negative role in the salinization of land adjacent to the coasts, causing a problem for soils in all its details represented in changing of the dissolved elements in soil. One of the most important natural factors that cause soil salinity is human activity in all its forms, and one of the most important causes of salinity is the phenomenon o

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Wed Apr 14 2021
Journal Name
Wireless Personal Communications
A Partial CSI Estimation Approach for Downlink FDD massive-MIMO System with Different Base Transceiver Station Topologies
...Show More Authors

Massive multiple-input multiple-output (massive-MIMO) is a promising technology for next generation wireless communications systems due to its capability to increase the data rate and meet the enormous ongoing data traffic explosion. However, in non-reciprocal channels, such as those encountered in frequency division duplex (FDD) systems, channel state information (CSI) estimation using downlink (DL) training sequence is to date very challenging issue, especially when the channel exhibits a shorter coherence time. In particular, the availability of sufficiently accurate CSI at the base transceiver station (BTS) allows an efficient precoding design in the DL transmission to be achieved, and thus, reliable communication systems can be obtaine

... Show More
View Publication
Scopus (6)
Crossref (6)
Scopus Clarivate Crossref
Publication Date
Thu Dec 19 2019
Journal Name
НАУЧНЫЙ ФОРУМ
EMOTIONALLY PAINTED VOCABULARY ON THE FIGHT AGAINST INTERNATIONAL TERRORISM IN MEDIA MATERIALS
...Show More Authors

The article considers the language of the mass media as a synthesis of the language means of all other styles of language. It is alleged that the newspaper and journalistic language actively uses foreign words and elements of words, replenishing the vocabulary of the language. It is noted that the lexical-semantic system of language is sensitive to socio-economic, political, cultural and scientific-technical changes. Attention is focused on the fact that one of the reasons that affect the change in the lexical composition of the language are the mass media. Thus, the language of the media is characterized by the use of a variety of neutral vocabulary, which, in conjunction with other words in atypical combinations for it, can acquire additi

... Show More
Publication Date
Tue Jan 01 2019
Journal Name
Journal Of Radiation Research And Applied Sciences
Determination of muon absorption coefficients in heavy metal elements
...Show More Authors

View Publication
Crossref (2)
Clarivate Crossref
Publication Date
Sat Oct 12 2019
Journal Name
Iop Conf. Series: Journal Of Physics: Conf. Series
Preparation of Some (Transition Metal-Flavylium Salt- Flavon) Complexes
...Show More Authors

Three ligands were prepared, spectroscopic method and elemental analysis verified their structures. The L1 and L2 ligands are flavylium salts while the third one L3 is a Flavon. The reactions between transition metal salts and the ligands have synthesized two groups of new metal complexes, one group contains L1, L3 coordinated with the metal ion. The other group contains L2, L3 and the metal. These complexes have been identified by available spectroscopic tools (UV-Visible and IR), the C.H.N results confirmed the proposed structures. The experimental data disclosed that the complexes were coordinated by 6the coordinate with mono-and bidentate ligands forming octahedral structure, in which L3 acts as monodentate and L1, L2 as bidentate ligan

... Show More
Preview PDF
Publication Date
Sun Jan 21 2024
Journal Name
Biomedicine
Detection of the effect of synthetic siRNA on efflux pump MexA gene expression and antibiotic resistance in clinical isolates of Pseudomonas aeruginosa
...Show More Authors

Introduction and Aim: Pseudomonas aeruginosa is a nosocomial infection with an ability to develop high levels of antibiotic resistance. The efflux pump system is one of the mechanisms that is linked to multidrug resistance in P. aeruginosa. In this study, we employed siRNA loaded on gold nanoparticles against the MexA efflux pump gene to decrease the MexA gene expression in P. aeruginosa and estimated antibiotic resistance after gene silencing.   Materials and Methods: This study examined four strains of P. aeruginosa isolated from patients in various hospitals in Baghdad. Bacteria isolated were identified by biochemical tests and Vitek compact 2 system.  Single-stranded siRNA (33bp) designed in this study was loaded onto gold

... Show More
View Publication
Crossref
Publication Date
Tue Jan 18 2022
Journal Name
مجلة ديالى للعلوم الصرفة
Study the gene expression of aacC1 gene in Acinetobacter baumannii that responsible for Aminoglycoside resistance
...Show More Authors

Publication Date
Mon May 09 2022
Journal Name
مجلة علوم ديالى
The expression of PmrA gene in Acinetobacter baumannii bacteria that is responsible for Colistin resistance
...Show More Authors