Preferred Language
Articles
/
ijl-230
Pulsed Er,Cr:YSGG Laser For Surface Modification of Dental Zerconia Ceramic
...Show More Authors

Background: Surface treatment of machined dental zirconia for enhancement of the adhesion to resin cement, using Er,Cr:YSGG  Laser. Materials and Methods: Total number of 42 zirconia disc specimens (9 mm diameter, and 2 mm height) was sintered according to the manufacturer instruction. They are divided into six groups, each group of seven samples. Laser groups (Experiment parameters) were depend on laser total irradiation time, pulse duration, and power. Group (A): 20 sec., 60 µs pulse duration. Group (B): 30 sec., 60 µs pulse duration. Group (C): 40 sec., 60 µs pulse duration. Group (D): 20 sec., 700 µs pulse duration. Group (E): 30 sec., 700 µs pulse duration, with different powers used (1, 1.50, 2, 2.50, 3, 3.50, 4) W. And finally group (N): untreated samples representing the control group. Luting cement was applied to laser treated zirconia sample’s surfaces and cured by light for 40 s. Then all sample surfaces were examined under a stereo microscope, for determining the depth mean values of the created pulse holes, for each specimen. The bond between the laser treated zirconia surfaces and the applied resin cement, were examined for all samples by using a universal testing machine, for determination of the shear bond strength values. Six additional specimens: one untreated sample and five other samples that were laser irradiated with the parameters that exhibited the highest shear bond strength values in each treated group, were examined for their average surface roughness by using an atomic force microscope. Another similar six specimens were also examined for their surface morphology, by using a scanning electron microscope. Both surface examination methods were performed by specialized operators. The bond failure modes were also examined by an optical microscope. Results obtained from shear bond strength test and laser pulse depth examination were statistically analyzed. Results: There was significant differences in the shear bond strength values, indicating a clear increase in zirconia-resin cement bonding, especially in group B (30 s, 60 µs, 4W), reaching  (8.63 Mpa). Whereas, the control group had (4.49 Mpa), and an enhanced zirconia surface average roughness, that group E (30 s, 700 µs, 3.5 W) specimen had the highest value (14.5nm), among the six examined specimens. While the control specimen had the least value examined which is (3.05nm). Conclusion: A relation between the cement bonding efficiency and the laser treated zirconia surface roughness, laser pulse depths was detected. The Er,Cr:YSGG laser pulse duration and  power is  crucial parameters in the surface roughness enhancement of the zirconia ceramic.

 

View Publication Preview PDF
Quick Preview PDF
Publication Date
Fri Feb 01 2019
Journal Name
Construction And Building Materials
Utilization of magnetic water in cementitious adhesive for near-surface mounted CFRP strengthening system
...Show More Authors

Cement-based adhesive (CBA) is used as a bonding agent in Carbon Fibre Reinforced Polymer (CFRP) applications as an alternative to epoxy-based adhesive due to the drawbacks of the epoxy system under severe service conditions which negatively affect the bond between the CFRP and strengthened elements. This paper reports the results of, an investigation carried out to develop two types of CBA using magnetized water (MW) for mixing and curing. Two magnetic devices (MD-I and MD-II), with different magnetic field strengths (9000 and 6000 Gauss) respectively, were employed for water magnetization. Different water flows with different water circulation times in the magnetizer were used for each device. Compressive and splitting tensile strength te

... Show More
Scopus (11)
Crossref (10)
Scopus Clarivate Crossref
Publication Date
Tue Jan 01 2019
Journal Name
Energy Procedia
Calculating Surface Roughness for a Large Scale SEM Images by Mean of Image Processing
...Show More Authors

View Publication
Scopus (25)
Crossref (26)
Scopus Clarivate Crossref
Publication Date
Sat Nov 30 2019
Journal Name
Journal Of Engineering And Applied Sciences
Distribution of Land Surface Temperatures from Satellite Images for Al-Hammar Marshes In Iraq
...Show More Authors

View Publication
Scopus Crossref
Publication Date
Sat Jan 02 2021
Journal Name
Al-qadisiyah Journal For Engineering Sciences
Improving the Moisture Damage Resistance of HMA by Using Ceramic Fiber and Hydrated Lime
...Show More Authors

The Moisture damage is considered as one of the main challenge for the experts in the field of asphalt pavement design. The aims of the present study is to modify moisture resistance of the asphalt concrete by utilizing ceramic fibers as a type of reinforcement incorporated with hydrated lime. For this purpose, a penetration grade of the asphalt cement (40-50) was utilized as a binder with an aggregate of the maximum nominal size of 12.5mm and mineral filler limestone dust. A series of specimens has been fabricated by utilizing 0.50, 1.0, 1.5, and 2.0 percentages of ceramic fibers. For each of these contents, another subsequent group of specimens with hydrated lime with 0.0, 1.0, 1.5, and 2.0 percentages were moulded. For the additi

... Show More
Crossref (1)
Crossref
Publication Date
Tue Oct 02 2018
Journal Name
Iraqi Journal Of Physics
Preparation of unsaturated polyester/nano ceramic composite and study electric, thermal and mechanical properties
...Show More Authors

The composites were manufactured and study the effect of addition of filler (nanoparticles SiO2 treated with silane) at different weight ratios (1, 2, 3, 4 and 5) %, on electrical, mechanical and thermal properties. Materials were mixed with each other using an ultrasound, and then pour the mixture into the molds to suit all measurements. The electrical characteristics were studied within a range of frequencies (50-1M) Hz at room temperature, where the best results were shown at the fill ratio (1%), and thermal properties at (X=3 %), the mechanical properties at the filler ratio (2%).

View Publication Preview PDF
Crossref (10)
Crossref
Publication Date
Tue Apr 13 2021
Journal Name
Neuroquantology
Sintering Additives Effects on the Microstructure and Electrical Behavior of Yttrium Oxide Ceramic Composites
...Show More Authors

Ceramics type Yttrium oxide with Silicon carbide. were selected to investigate its sintered density, microstructure and electrical properties, after adding V2O5, of 100 nm grain size. Different weight percentages ranging from (0.01,0.02,0.03 and 0.04) were used. Dry milling applied for twelve hours. The pelletized samples were sintered at atmospheric of static air and at sintering temperature 1400 ˚C, for three hours. The crustal structure test shoes the phase which is yttrium silicon carbide Scanning electron microscopy, scan sintered microstructure. Samples after sintering were electrically investigated by measuring its capacitance, dielectric constant and their results showed increasing after added V2O5 particles at the combinat

... Show More
View Publication Preview PDF
Scopus Crossref
Publication Date
Mon Dec 21 2020
Journal Name
Frontiers In Medicine
Anxiety, Practice Modification, and Economic Impact Among Iraqi Dentists During the COVID-19 Outbreak
...Show More Authors

Objectives: As health care workers on the front line during the coronavirus (COVID-19) pandemic, dental practitioners are amongst those at risk due to their close contact with potentially infected individuals. The aim of the current study was to assess the anxiety, awareness practice modification, and economic impact amongst Iraqi dentists whilst working during the outbreak.

Methods: This study was performed using an online survey questionnaire with aid of Google forms from 2nd to 23rd July 2020. A total of 484 clinicians responded. The questionnaire was composed of open end, closed end, and Likert five-point scale questions to assess anxiety, awareness and financial impa

... Show More
View Publication Preview PDF
Crossref (33)
Crossref
Publication Date
Mon Jan 01 2018
Journal Name
Biochemical And Cellular Archives
Optimization of enzymatic conversion of waste office paper using response surface methodology for bioethanol production
...Show More Authors

Scopus
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
Sat Dec 15 2018
Journal Name
Journal Of The College Of Education For Women
The Reasons for the Behavior of Bullying school Students in the first grade average from the point of view of teachers and teachers and methods of modification
...Show More Authors

 هدف البحث التعرف الى اسباب سلوك التنمر لدى طلاب الصف الاول المتوسط من وجهة نظر المدرسين والمدرسات واساليب تعديله، واستعمل الباحثان المنهج الوصفي واختيار عينة عشوائية من المدرسين والمدرسات في متوسطة أرض الرافدين ومتوسطة الرحمن للبنين وكان عددهم (46) مدرساً ومدرسة بواقع (32) مدرساً و(14) مدرسة، واعتمد الباحثان الاستبانة أداة للتعرف الى اسباب سلوك التنمر واساليب تعديله، واشارت نتائج البحث الى تنوع اسباب التن

... Show More
View Publication Preview PDF