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The effect of in office bleaching on surface roughness and micro-hardness of newly developed composite materials (In vitro study)
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Background: Alterations in the microhardness and roughness are commonly used to analyze the possible negative effects of bleaching products on restorative materials. This in vitro study evaluated the effect of in-office bleaching (SDI pola office +) on the surface roughness and micro-hardness of four newly developed composite materials (Z350XT –nano-filled, Z250XT-nano-hybrid, Z250-mico-hybrid and Silorane-silorane based). Materials and methods: Eighty circular samples with A3 shading were prepared by using Teflon mold 2mm thickness and 10mm in diameter. 20 samples for each material, 10 samples for base line measurement (surface roughness by using portable profillometer, and micro-hardness by usingDigital Micro Vickers Hardness Tester), and 10 samples for after bleaching measurement. The appropriate bleaching procedure was performed on the top surface of test groups for 90 minutes total bleaching period. Then surface roughness and hardness were tested at the end of the duration. Statistical analysis was carried out using ANOVA, LSD and t-test. Results: There was a highly significant increase in surface roughness of all tested groups after bleaching. There is a highly significant increase in micro-hardness for Z250, there is decrease in Micro-hardness for siloraneand Z250xt and there is a non-significant increase in micro-hardness of Z350xt. Conclusion: bleaching has a negative effect on surface roughness of all the tested materials, as surface roughness increased after bleaching. Micro-hardness is a material dependent, there is different reaction to bleaching depending on the resin, load and size of the fillers used in the materials. Nano-filled composite is the material that has better performance than the other tested materials, as it is the material that has the least affection by bleaching.

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Publication Date
Thu Oct 01 2015
Journal Name
Applied Research Journal
Experimental Study of the Behavior of Composite Concrete Castellated Steel Beams Subjected to Pure Bending
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The aim of this study is to investigate the behavior of composite castellated beam in which the concrete slab and steel beam connected together with headed studs shear connectors. Four simply supported composite beams with various degree of castellation were tested under two point static loads. One of these beams was built up using standard steel beam, i.e. without web openings, to be a reference beam. The other three beams were fabricated from the same steel I-section with various three castellation ratios, (25, 35, and 45) %. In all beams the concrete slab has the same section and properties. Deflection at mid span of all beams was measured at each 10 kN load increment. The test results show that the castellation process leads to

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Publication Date
Thu Dec 01 2022
Journal Name
Case Studies In Construction Materials
Experimental study of temperature effect on the mechanical tensile fatigue of hydrated lime modified asphalt concrete and case application for the analysis of climatic effect on constructed pavement
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Previous experimental studies have suggested that hot mixed asphalt (HMA) concrete using hydrated lime (HL) to partially replace the conventional limestone dust filler at 2.5% by the total weight of all aggregates showed an optimum improvement on several key mechanical properties, fatigue life span and moisture susceptibility. However, so far, the knowledge of the thermal response of the modified asphalt concrete and thermal influence on the durability of the pavement constructed are still relatively limited but important to inform pavement design. This paper, at first, reports an experimental study of the tensile fatigue life of HMA concrete mixes designed for wearing layer application. Tests were conducted under three different temperatur

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Publication Date
Thu Apr 14 2016
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
Study The Effect of α-amylase Inhibitors Isolated from Plant Sources on Some Mold.: Study The Effect of α-amylase Inhibitors Isolated from Plant Sources on Some Mold.
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Activity test of the inhibitors purified from barley and broad beans crop proved the inhibition activity against 6 types of rots Pencillium ssp and Aspergellusflavus and Aspergillus niger and Fusarium solani and Fusarium semitectum and Mucor with three concentrations 0.1 and 0.2 and 0.3 mg/ml, where the inhibitor purified from the second peak of broad beans proved that it had a higher inhibition activity against the growth of test rots which were 53.75 and 62.5 and 78.5 and 76.25 and 84 and 18.8% respectively, at 0.3 mg/ ml followed by the first peak of the inhibitor purified from broad beans the inhibition activity were 43.75 and 50 and 62.96 and 75 and 80 and 12.5 then the inhibitor purified from barley in which the inhibition activity

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Publication Date
Tue May 01 2018
Journal Name
Photomedicine And Laser Surgery
In Vitro Influence of Low-Power Diode Laser Irradiation Time on Human Red Blood Cells
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Objective: The present study investigates whether the exposure to low-power diode laser induces denaturation in red blood cell (RBC) membrane protein composition, and determines the irradiation time for when denaturation of membrane protein process begins. Background: A low-energy laser has been used extensively in medical applications. Several studies indicated significant positive effects of laser therapy on biological systems. In contrast, other studies reported that laser induced unwanted changes in cell structure and biological systems. The present work studied the effect of irradiation time of low-power diode laser on the structure of membrane proteins of human RBCs. Materials and methods: The RBC suspension was divided into five equa

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Publication Date
Thu Jun 30 2022
Journal Name
International Journal Of Drug Delivery Technology
Physiological and Immunological Assessment in Infertile Women Undergoing In-vitro Fertilization
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All the available reports on the issue of infertility confirmed the increase in this population problem worldwide. Although the accurate estimate of the number of infertile people is due to several reasons, including the discrepancy in the true definition of infertility (whether it extends for one, two or five years of failed pregnancy attempts), as well as the great discrepancy in the size of the selected population groups (large population sample size versus epidemiological studies) and defining the category that diagnosed included (individuals, women, or couples). The goal of today’s IVF program is to obtain high-quality embryos with high efficiency in development, which leads to an increase in live birth rates.

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Publication Date
Mon Jan 01 2024
Journal Name
Baghdad Science Journal
Surface Modification of the Improved Stainless Steel Alloy AISI-304 and the Use of Diffusion Coating and a Study of Its Efficiency in Resistivity Hot Corrosion in an Atmosphere of Sodium Chloride Vapor NaCL and Sodium SulfateNa_2 SO_4
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       This research aims to modify the components of stainless steel alloy by the method of surface engineering through the single diffusion coating technique in order to obtain new alloys with high efficiency in resisting harsh environmental conditions. Steam a mixture of sodium chloride ( ) and sodium sulfate ( ) at a temperature of 900 and then compare it with the base alloy. The results showed that the alloys produced in this way are very efficient. The results showed that the aluminum coating showed high efficiency in resisting oxidation and provided better protection for a longer time compared to the uncoated alloy due to the  oxide crust layer formed with high adhesion as well as the aluminum-rich phases, whether the phase

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Publication Date
Fri Aug 31 2012
Journal Name
Al-khwarizmi Engineering Journal
Study of Mechanical Properties of (Al-Cu-Mg) Alloy Matrix Composite
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The present research had dealt with preparing  bars  with the length of about  (13 cm) and  adiametar  of  (1.5 cm) of composite materials with metal  matrix  represented by (Al-Cu-Mg) alloy cast enforced by (ZrO2) particles with chosen weight  percentages (1.5, 2.5 ,3.5, 5.5 %). The base  cast and the composite  materials were prepared by casting method by uses vortex  Technique inorder to  fix up (ZrO2) particles in homogeneous way on  the  base cast. In addition to  that, two main groups of composite materials were prepared depending on the particles size of (ZrO2) , respectively.       &n

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Publication Date
Mon Feb 04 2019
Journal Name
Iraqi Journal Of Physics
A study of the Zn:Sn mixing ratio effect on the gas detector properties
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Semiconductor-based metal oxide gas detector of five mixed from zinc chloride Z and tin chloride S salts Z:S ratio 0, 25, 50, 75 and 100% were fabricated on glass substrate by a spray pyrolysis technique. With thickness were about 0.2 ±0.05 μm using water soluble as precursors at a glass substrate temperature 500 ºC±5, 0.05 M, and their gas sensing properties toward CH4, LPG and H2S gas at different concentration (10, 100, 1000 ppm) in air were investigated at room temperature which related with the petroleum refining industry.
Furthermore structural and morphology properties were scrutinize. Results shows that the mixing ratio affect the composition of formative oxides were (ZnO, Zn2SnO4, Zn2SnO4+ZnSnO3, ZnSnO3, SnO2) ratios ment

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Publication Date
Mon Apr 09 2018
Journal Name
Al-khwarizmi Engineering Journal
Study the Effect of Forming Media on the Hydroforming Process for Copper Tube
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To observe the effect of media of the internal pressure on the equivalent stress distribution in the tube, an experimental study is done by constructing a testing rig to apply the hydraulic pressure and three dies are manufactured with different bulging configurations (square, cosine, and conical). In the other part, ANSYS APDL is generated to analyze the bulging process with hydraulic and rubber (natural and industrial) media. It was found that when the media is a rubber, the stress is decreased about 9.068% in case of cosine die and 5.4439% in case of conical die and 2.8544% in case of square die. So, it can be concluded that the internal pressure in the rubber media is much better than in hydraulic media. Also, the force needed for fo

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Publication Date
Mon Oct 13 2025
Journal Name
Mesopotamian Journal Of Cybersecurity
Improvement of the Face Recognition Systems Security Against Morph Attacks using the Developed Siamese Neural Network
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Face Recognition Systems (FRS) are increasingly targeted by morphing attacks, where facial features of multiple individuals are blended into a synthetic image to deceive biometric verification. This paper proposes an enhanced Siamese Neural Network (SNN)-based system for robust morph detection. The methodology involves four stages. First, a dataset of real and morphed images is generated using StyleGAN, producing high-quality facial images. Second, facial regions are extracted using Faster Region-based Convolutional Neural Networks (R-CNN) to isolate relevant features and eliminate background noise. Third, a Local Binary Pattern-Convolutional Neural Network (LBP-CNN) is used to build a baseline FRS and assess its susceptibility to d

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