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The effect of nano-hydroxy apatite on re-mineralize white spot lesions prior to orthodontic adhesive removal by different techniques (An In vitro comparative study)
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Background: White-spot lesion is one of the problems associated with the fixed orthodontic treatment. The aims of this in-vitro study were to investigate enamel damage depth on adhesive removal when the adhesive were surrounded by sound, demineralized or demineralized enamel that had been re-mineralized prior to adhesive removal using 10% Nano-Hydroxy apatite and to determine the effect of three different adhesive removal techniques. Materials and methods: Composite resin adhesive (3M Unitek) was bonded to 60 human upper premolars teeth which were randomly divided in to three groups each containing ten sound teeth and ten teeth with demineralized and re-mineralized lesions adjacent to the adhesive. A window of 2 mm was prepared on the buccal surface of the tooth and painted with an acid resistant nail varnish except for the window.The demineralized enamel produced by immersion of teeth in demineralization buffer for 12 days.half of the demineralized window, was covered with acid –resistant red nail varnish, and the samples were then subjected to re-mineralization with 10% of nano hydroxyapatite. The adhesive was removed with either :(1) fiber reinforced composite bur in slow speed handpiece (SS); (2)12 fluted long flame carbide bur in high speed handpiece (HS); (3) ultrasonic scaler (US).damage to the enamel was assessed using stereomicroscope with grid eye piece. Results: the greatest to least mean depth of damage with three different adhesive removal techniques to sound enamel was HS˃ US ˃SS and to demineralized and re-mineralized enamel were SS ˃US˃ HS. Sound enamel had the least amount of damage. Re mineralization before the adhesive removal highly significant reduced the amount of damage produced by all techniques compared with demineralized enamel. Conclusions: When the demineralized enamel was present 12 fluted long flame carbide bur were found to be the least damage in adhesive removal technique and re-mineralization further reduced the amount of enamel damage

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Publication Date
Sat Oct 20 2018
Journal Name
Journal Of Economics And Administrative Sciences
Calculate the Average Run Length (ARL) to Detect the Deviation in the Process A case Study in an Industrial Organization
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Statistical control charts are widely used in industry for process and measurement control . in this paper we study the use of markov chain approach in calculating the average run length (ARL) of cumulative sum (Cusum) control chart for defect the shifts in the mean of process , and exponentially weighted moving average (EWMA) control charts for defect the shifts for process mean and , the standard deviation . Also ,we used the EWMA charts based on the logarithm of the sample variance for monitoring a process standard deviation when the observations (products are selected from al_mamun factory ) are identically and independently distributed (iid) from normal distribution in continuous manufacturing .

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Publication Date
Wed May 24 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Science
Direct and Indirect Spectrophotometric Determination of Paracetamol in Pharmaceutical Preparations By Oxidative Coupling With p-Amino-2-hydroxy Sodium Benzoate
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New simple and sensitive spectrophotometric methods for the determination of paracetamol in aqueous medium were developed. The first method is based on coupling of paracetamol with p-amino-2-hydroxy sodium benzoate (AHB) in the presence of sodium periodate, as oxidizing agent, to form a brownish-orange compound which shows a λmax at 470 nm. The molar absorptivity (εmax) of the colored product was found to be (3371) l. mole1. cm-1 and Sandel’s index 0.0449 μg. cm-2. The method follows Beer’s law in the concentration range of 12.5-500.0 μg of paracetamol in a final volume of 25 ml (0.5-20.0) μg. ml-1 with relative standard deviation percent (RSD%) ranged between 0.26-4.71% and accuracy, expressed by recovery percent, 95-106% for five

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Publication Date
Wed May 24 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Direct and Indirect Spectrophotometric Determination of Paracetamol in Pharmaceutical Preparations By Oxidative Coupling With p-Amino-2-hydroxy Sodium Benzoate
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 New simple and sensitive spectrophotometric methods for the determination of paracetamol in aqueous medium were developed. The first method is based on coupling of paracetamol with p-amino-2-hydroxy sodium benzoate (AHB) in the presence of sodium periodate, as oxidizing agent, to form a brownish-orange compound which shows a λmax at 470 nm. The molar absorptivity (εmax) of the colored product was found to be (3371) l.mole1.cm-1 and Sandel’s index 0.0449 μg.cm-2. The method follows Beer’s law in the concentration range of 12.5-500.0 μg of paracetamol in a final volume of 25 ml (0.5-20.0) μg.ml-1 with relative standard deviation percent (R.S.D%) ranged between 0.26-4.71% and accuracy, expressed by recover

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Publication Date
Fri Oct 20 2023
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
The Gas Sensitivity Properties of Nano Ferrite CuxAl0.3-XNi0.7Fe2O4 Synthesized by Sol-Gel Method
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This study includes the preparation of the ferrite nano ferrite CuxAl0.3-XNi0.7Fe2O4 (where: x = 0, 0.05, 0.1, 0.15, 0.2, 0.25, 0.3) M using the auto combustion method (sol-gel), and citric acid was used as fuel for auto combustion. The ferrite samples were checked by X-ray diffraction (XRD), Field Emission Scanning Electron Microscopes (FE-SEM), and energy dispersive X-ray analyzer (EDX). They showed that the prepared compound has a face-centered cubic structure (FCC). The lattice constant increases with an increase in the percentage of doping of the copper ions, and a decrease for the aluminum ion and that the compound is porous and its grains are spherical, and there are no other

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Publication Date
Wed Nov 14 2018
Journal Name
Journal Of Engineering And Applied Sciences
DEMONSTRATE OF MAGNETIC FIELD EFFECT ON THE CAPABILITY OF ADSORPTION PROCESS IN THE REMOVAL OF AZO DYE FROM THE AQUEOUS SOLUTIONS ON CALCINED IRAQI BENTONITE CLAY MINERAL VIA COLUM
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Publication Date
Wed Jul 01 2020
Journal Name
Journal Of Engineering
Study the Effect of Catalyst -to- Oil Ratio Parameter (COR) on Catalytic Cracking of Heavy Vacuum Gas Oil
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This work deals with the production of light fuel cuts of (gasoline, kerosene and gas oil) by catalytic cracking treatment of secondary product mater (heavy vacuum gas oil) which was produced from the vacuum distillation unit in any petroleum refinery. The objective of this research was to study the effect of the catalyst -to- oil ratio parameter on catalytic cracking process of heavy vacuum gas oil feed at constant temperature (450 °C). The first step of this treatment was, catalytic cracking of this material by constructed batch reactor occupied with auxiliary control devices, at selective range of the catalyst –to- oil ratio parameter (  2, 2.5, 3 and 3.5) respectively.  The conversion of heavy vacuum gas

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Publication Date
Tue Jun 15 2021
Journal Name
Al-academy
Abstract Expressionist features in drawings by Eric Bartot and Serwan Baran " A Comparative Study": علي ابراهيم مردان
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  Amidst the changes resulting from the subject matter of expression in art. The necessity of searching for the expressive features of thought that leaves different imprints with aesthetic features and values which called for re-modifying the expressive vision of contemporary drawings. Therefore, this research has been concerned with the study of (abstract expressive features in the drawings of (Serwan Baran) and (Eric Barto) - a comparative study), and the research includes four chapters. The first chapter is devoted to explaining the research problem, its importance, need, purpose, and limits, then determining the most important terms mentioned in it. Where the research problem dealt with the subject of abstract expressive feature

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Publication Date
Fri Nov 24 2023
Journal Name
Iraqi Journal Of Science
Evaluation Cytotoxic Effect of Nostoc sp. and Scenedesmus acuminatus Extracts on Cell Line Hep -2 in vitro
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In this Study, isolate and identification two types of algae Scenedesmus acuminatus (Lag.) Chodat belonging to Division of green –algae and Nostoc sp. Of the belong to Division of cyanobacteria from fountain pool at the University of Al- Mustansiriya. Use culture medium Chu- 10 for growth of algae on batch culture in the laboratory conditions (25 ˚ c ±2 and light intensity 200 μE/m²/sec the light:dark regime was used 16:8 hrs). Harvested culture after fourteen days of age farm. Use methanol 95% to extract active compound from raw dry biomass, Tested the effectiveness of the efficiency of the cell extract toward the cell line (human larynx cancer) Hep-2 from biotechnology center at the University of Alnahrain university and differen

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Publication Date
Fri Nov 24 2023
Journal Name
Iraqi Journal Of Science
Effect of Different Percentages of Titanium Dioxide Additives on the Enamel Protecting of Steel Surface
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This work involves the development of ceramic coating to steel surfaces (enamel).This enamel high quality consisted of two ceramic layers to ensure excellent bonding with the steel surfaces. The first is called the ground coat which proved bonding between the steel base and the second outer layer called the cover coat. Various concentrations of TiO2 were separately added to the mixture of the cover coat, resulting in to much better densification of the ceramic outer layer, the hardness, thermal shock resistances, and glossiness were improved also .Moreover this addition has raised the corrosion resistances of the ceramic in harsh acidic environment and at higher temperatures Also this enamel was used to protect the surfaces of steels whi

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Publication Date
Thu Jan 30 2025
Journal Name
Journal Of Baghdad College Of Dentistry
An in vitro evaluation of fit of the crowns fabricated by zirconium oxide-based ceramic CAD/CAM systems, before and after porcelain firing cycles and after glaze cycles
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Background: The objective of this in vitro study was to evaluate the vertical marginal fit of crowns fabricated with ZrO2 CAD/CAM, before and after porcelain firing cycles and after glaze cycles. Materials and Methods: An acrylic resin model of a left maxillary first molar was prepared and duplicated to have Nickel-Chromium master die. Ten die stone dies were sent to the CAD/CAM (Amann Girrbach) for crowns fabrication. Marginal gaps along vertical planes were measured at four indentations at the (mid mesial, mid distal, mid buccal, mid palatal) before (Time 0) and after porcelain firing cycles (Time 1) and after glaze cycles (Time 2) using a light microscope at a magnification of ×100. One way ANOVA LSD tests were performed to determine wh

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