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An Evaluation of Some Mechanical Properties of Autopolymerizing Acrylic Resin with the Modified One after Changing the Curing Environment: (In vitro Study)
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Background: Studying and investigating the transverse strength(Ts), impact strength(Is), hardness (Hr) and surface roughness(Ra) of conventional and modified autopolymerizing acrylic resin with different weight percentages of biopolymer kraftlignin, after curing in different water temperatures; 40°C and 80°C. Material and Methods: Standard acrylic specimens were fabricated according to ADA specification No.12 for transverse strength, ISO 179 was used for impact testing, Shore D for hardness and profilometerfor surface roughness. The material lignin first dispersed in the monomer, then the powder PMMA is immediately added. Ligninadded in different weight percentages. Then cured using pressure pot (Ivomet) in two temperatures;40°C and 80°C under 2 bar pressure, for 30 minutes.Atotal of 144samples were prepared for this study. Ts, Is, Ra, and Hr were tested, by using Instron universal testing machine, charpy impact tester, shore D tester, and profilometer respectively. Results: The transverse strength increased in both the conventional and modified onewhen compared with that cured in air. The addition of 0.5wt% lignin gave the higher effect (78.0017MPa) with highly significant difference found between groups at 40°C polymerizing temperature. While the impact strength in both temperatures in the modified resin revealed increased results than conventional one, 1.25wt% of kraft lignin gave the highest value (12.7355KJ/m2) with highly significant differences found between groups at 80°C polymerizing temperature. Hardness and surface roughness showed also highly significant differences found between groups at 40°C polymerizing temperature, all the groups had increased Hr. than the control one (78.95), while the Ra. decreased for 1.0% ,1.25,1.50 and 1.75 wt% lignin content to (0.26,0.10,0.063, 0.12µm) respectively in 40°C polymerizing temperature, the lowest value present in 1.75 wt% lignin (0.05 µm) at 80°Cpolymerizing temperature. Conclusions: It seems that increasing the polymerizing temperature to 40°C had a positive effect on the mechanical properties of autopolymerizing acrylic resin and the one enforced by kraft lignin biopolymer in low percentages. Increasing the polymerizing temperature to 80°C will doesn’t have much positive effect but it doesn’t deteriorate the mechanical properties. However, when submitted to increasing the temperature to 80°C, specimens showed a significant increase in impact strength.

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Publication Date
Mon Mar 13 2017
Journal Name
Journal Of Baghdad College Of Dentistry
A study to compare the internal fitness and marginal gap between single crowns and crowns within three-unite bridge of zirconia substructure fabricated by CAD-CAM system. (An In vitro study)
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ABSTRACT Purpose: the aim of this in vitro study was to compare the marginal gap and internal fitness between single crowns and the crowns within three-unit bridges of zirconium fabricated by CAD-CAM system. Materials and methods: A standard model from ivoclar company was used as a pattern to simulate three-units bridge (upper first molar and upper first premolar) as abutments used to fabricate stone models, eight single crowns for premolar and eight of three units bridges. Crowns and bridges fabricated by CAD-CAM system were cemented on their respective stone models then sectioned at the mid-point buccolingaully and misiodistaly and examined under stereomicroscope. Result: the marginal gap in premolar crowns and premolar within bridge we

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Publication Date
Thu Aug 31 2017
Journal Name
Journal Of Engineering
Urban agriculture as one of the ecological applications of the regenerative city
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Recently, several concepts and expressions have emerged that have often preoccupied the world . around the concept of environment and sustainability. This is due to the negative and irresponsible impact of man and his innovations in various industrial and technological fieldsthat have damaged the natural environment. Architecture and cities at the broader level are some of the man made components that caused these negative impacts and in the same time affected by them. What distinguishes architectural and urban projects is the consumption of large . quantities of natural resources and production larger amounts of waste and pollution, along the life of these projects. At the end of the twentieth century and the beginning of the twenty-fir

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Publication Date
Sun Dec 06 2009
Journal Name
Baghdad Science Journal
Seasonal Changes of Nutrient Concentrations in Water of Some Locations in Southern Iraqi Marshes, After Restoration.
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After restoration of Iraqi marshes during 2003, three locations were chosen, one in each main marsh (Um Al-Naaj site in Al-Hwaizeh marsh; Al-Nagarah site in Al-Hammar marsh and Al-Baghdadia site in Al-Chebaysh marsh) to determine the concentrations of nutrients (Nitrate, Nitrite, Phosphate and Silicate) in water seasonally for the period winter, spring, summer, and autumn at 2007. Five water replicates were collected from each site, seasonally. In the Lab., the samples were analyzed by colorimetric methods; the results showed that Um-Al-Naaj site has the highest nutrients level, while Al-Nagarah site has the lowest level. The statistical program t-test was applied at the significant levels (P-value < 0.01) and (P-value < 0.05) to know

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Publication Date
Fri Jan 20 2023
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Evaluation of Osteocalcin and Some Biochemical Marker in Diabetes Mellitus Iraqi Women's patients with Osteoporosis
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Diabetes mellitus is a set of metabolic diseases, the most prevalent of which is chronic hyperglycemia. The culprits include insulin synthesis, insulin action, or both. Osteoporosis is a progressive systemic skeletal disorder defined by decreased bone mass and micro architectural degeneration of bone tissue, resulting in increased bone fragility and fracture risk, according to the World Health Organization (WHO). The degree of Nervosa damage determines how much a diabetic patient's body has been compromised. The current study's goal is an estimation: Age, BMI, FBS, HbA1C, D3, ALP, Ca, P, and Osteocalcin in Iraqi T2DM Women's patients with and without Osteoporosis. Three vitamins are required for Osteocalcin biosynthesis: vitamin K for Gla f

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Publication Date
Fri Jan 20 2023
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Evaluation of Osteocalcin and Some Biochemical Marker in Diabetes Mellitus Iraqi Women's patients with Osteoporosis
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Diabetes mellitus is a set of metabolic diseases, the most prevalent of which is chronic hyperglycemia. The culprits include insulin synthesis, insulin action, or both. Osteoporosis is a progressive systemic skeletal disorder defined by decreased bone mass and micro architectural degeneration of bone tissue, resulting in increased bone fragility and fracture risk, according to the World Health Organization (WHO). The degree of Nervosa damage determines how much a diabetic patient's body has been compromised. The current study's goal is an estimation: Age, BMI, FBS, HbA1C, D3,  ALP, Ca, P, and  Osteocalcin in Iraqi T2DM Women's patients with and without Osteoporosis. Three vitamins are required for Osteocalcin biosynthesis: vitamin K fo

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Publication Date
Tue Mar 28 2023
Journal Name
International Journal Of Dentistry
The Effect of Different Obturation Techniques in Primary Teeth on the Apical Microleakage using Endoflas: A Comparative In Vitro Study
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Objectives. This study was carried out to quantitatively evaluate and compare the sealing ability of Endoflas by using differentobturation techniques. Materials and Methods. After 42 extracted primary maxillary incisors and canines were decoronated, theircanals were instrumented with K files of size ranging from #15 to #50. In accordance with the obturation technique, the sampleswere divided into three experimental groups, namely, group I: endodontic pressure syringe, group II: modified disposable syringe,and group III: reamer technique, and two control groups. Dye extraction method was used for leakage evaluation. Data wereanalyzed using one-way ANOVA and Dunnett’s T3 post hoc tests. The level of significance was set at p<0:05. Results.

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Publication Date
Tue Jul 04 2023
Journal Name
Qalaai Zanist Scientific Journal
The Role of The Environmental Observer and The Environmental Police in Protecting the Environment in Iraqi Law
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Publication Date
Mon Jan 09 2012
Journal Name
Воронеж. гос. ун-т
STRUCTURAL-SEMANTIC FEATURES OF ONE-COMPONENT SENTENCES IN THE PLAYS OF A.N. OSTROVSKY
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Publication Date
Thu Jun 19 2025
Journal Name
Journal Of Baghdad College Of Dentistry
Evaluation of nano surface modification on CPTi dental implant using chemical method: mechanical and histological evaluation
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Background The application of nanotechnology to biomedical surfaces is explained by the ability of cells to interact with nanometric features. The aim of this study was to consider the role of nanoscale topographic modification of CPTi dental implant using chemical etching method for the purpose of improving osseointegration. Materials and methods: Commercial pure titanium rod was machined into 20 dental implants. Each implant was machined in diameter about 3mm, length of 8mm (5mm was threaded part and 3mm was flat part). Implants were prepared and divided into 2 groups according to the types of surface modification method used: 1st group (10 implant) remained without nano surface modification (control), 2nd group include (10 implant) etche

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Publication Date
Tue Apr 18 2023
Journal Name
Al–bahith Al–a'alami
The Visual intertextuality of normalization with Israel in websites of oriented satellite channels: An Analytical study of Al Hurrah Channel
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The research aims to reveal the methods of visual intertextuality used in the websites of the oriented satellite channel which is Arabic-speaking when addressing normalization with Israel. It also indicates the sources and types of intertextual images, the methodological and semiotic mechanisms for analyzing the intertextuality of news images used on the website of Alhurra satellite channel for the period from 1/6 - 30/8/2022, which included (94) images. The researcher analyzed (37) images with intertextual dimensions, excluding (57) images, which did not carry connotations connected with the inputs and objectives of the research.

The research reach

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