Preferred Language
Articles
/
jbcd-1868
Discoloration of Stretched Clear Elastomeric Chains by Dietary Media (An in vitro study)
...Show More Authors

Background: With the increasing demand on esthetic orthodontic appliances, discoloration of clear elastomeric chains and modules remains an issue which concerns both orthodontics and patients. This in vitro study was conducted to evaluate the effect of exposing stretched clear elastomeric chains from six different companies (Ortho Technology, Ormco, Ortho Organizer, American Orthodontics, Opal and G&H companies) to three types of dietary media (tea, coffee and turmeric). Materials and methods: A total of 960 lengths of six modules were cut from short type elastomeric chain; 160 pieces from each brand. The specimens were stretched 50%, placed on plastic boards, and incubated in water at 37°C for 1 day, 7 days, 14 days and 28 days. Once a day, the specimens were immersed for ten minutes in the testing dietary media, washed and then returned back to the water container. Color measurements were made before and after incubation of the specimens. Digital image were taken by an SLR digital camera and the color changes were calculated according to CIE L*a*b* color space system by Adobe Photoshop program. The resulting data were statistically analyzed using ANOVA and LSD tests. Result: Elastomeric chains from AO, Opal and G&H companies were the most brands prone to discoloration. Ortho Organizers and Ortho Technology chains were the least prone to discoloration. Tea, coffee and turmeric solutions discolored elastomeric chains from all companies in a variable degree, however turmeric caused significantly more discoloration, followed by tea and least by coffee. The amount of discoloration caused by tea and coffee increases gradually to peak at 28 days, while most of the discoloration caused by turmeric was in the first day and reached a plateau in a week. Conclusion: To decrease the discoloration of clear elastomeric chains the consumption of colored dietary media especially spices like turmeric are to be discouraged.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Sun Sep 01 2013
Journal Name
Baghdad Science Journal
Spectrophotometric Determination of Bismuth(III) with 4-(2-pyridylazo) Resorcinol-Application to Waters and Veterinary Preparation
...Show More Authors

This paper describes the development of a simple spectrophotometric determination of bismuth III with 4-(2-pyridylazo) resorcinol (PAR) in aqueous solution in the presence of cetypyridinium chloride surfactant at pH 5 which exhibits maximum absorption at 532 nm. Beer's law is obeyed over the range 5-200 µg/25 mL. i.e. 0.2-8 ppm with a molar absorptivity of 3×104 l.mol-1.cm-1 and Sandell's sensitivity index of 0.0069 µg.cm-2. The method has been applied successfully in the determination of Bi (III) in waters and veterinary preparation.

View Publication Preview PDF
Crossref
Publication Date
Tue Mar 01 2011
Journal Name
Journal Of Kufa For Chemical Science
systhesis,spectral and kinetic of N2O2macrocycle ligand with divalent metal ions ( Co , Ni and Cu ) complexes
...Show More Authors

Publication Date
Sun Sep 05 2010
Journal Name
Baghdad Science Journal
Design and Testing a Neutrons and Gamma-Rays Multilayer Shield Using Different Groups of Cross – Sections
...Show More Authors

A preventing shield for neutrons and gamma rays was designed using alternate layers of water and iron with pre-fixed dimensions in order to study the possibility of attenuating both neutrons and gamma-rays. ANISN CODE was prepared and adapted for the shield calculation using radiation doses calculation: Two groups of cross-section were used for each of neutrons and gamma-rays that rely on the one – dimensional transport equation using discrete ordinate's method, and through transforming cross-section values to values that are independent on the number of groups. The memory size required for the applied code was reduced and the results obtained were in agreement with those of standard acceptable document samples of cross –section, this a

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Jun 29 2022
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Constructed Wetland Units Filled with Waterworks Sludge for Remediating of Wastewater Contaminated with Congo Red Dye
...Show More Authors

The disposal of textile effluents to the surface water bodies represents the critical issue especially these effluents can have negative impacts on such bodies due to the presence of dyes in their composition. Biological remediation methods like constructed wetlands are more cost-effective and environmental friendly technique in comparison with traditional methods. The ability of vertical subsurface flow constructed wetlands units for treating of simulated wastewater polluted with Congo red dye has been studied in this work. The units were packed with waterworks sludge bed that either be unplanted or planted with Phragmites australis and Typha domingensis. The efficacy of present units was evaluated by monitoring of DO, Temperature, COD

... Show More
View Publication Preview PDF
Crossref (8)
Crossref
Publication Date
Sun Oct 01 2017
Journal Name
Journal Of Engineering
Experimental Evaluation of the Strut-and-Tie Model Applied to Deep Beam with Near-Load Openings
...Show More Authors

It is commonly known that Euler-Bernoulli’s thin beam theorem is not applicable whenever a nonlinear distribution of strain/stress occurs, such as in deep beams, or the stress distribution is discontinuous. In order to design the members experiencing such distorted stress regions, the Strut-and-Tie Model (STM) could be utilized. In this paper, experimental investigation of STM technique for three identical small-scale deep beams was conducted. The beams were simply supported and loaded statically with a concentrated load at the mid span of the beams. These deep beams had two symmetrical openings near the application point of loading. Both the deep beam, where the stress distribution cannot be assumed linear, and the ex

... Show More
View Publication Preview PDF
Publication Date
Sun Jun 20 2021
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
PETROLOGY AND PROVENANCE OF THE NATURAL STONE TOOLS FROM Al-DALMAJ ARCHAEOLOGICAL SITE, MESOPOTAMIAN PLAIN, IRAQ
...Show More Authors

Many stone tools were found on a hill south of the Hor Al-Dalmaj which is located in the central part of the alluvial plain of Mesopotamia, between the Tigris and Euphrates Rivers. The types of rocks from which the studied stone tools were made are not found in the alluvial plain, because it consists of friable sand, silt, and clay. All existing sediments were precipitated in riverine environments such as point bar, over bank, and floodplain sediments. The collected stone tools were described with a magnifying glass (10 x) and a polarized microscope after they were thin sectioned. Microscopic analysis showed that these stone tools are made of sedimentary, volcanic igneous and metamorphic rocks, such as: sandstones, limestones, chert, con

... Show More
View Publication Preview PDF
Scopus (1)
Scopus Crossref
Publication Date
Wed Jun 13 2012
Journal Name
Journal Of Kerbala University
Thermo physical behaviour of binary and ternary systems for cyclohexanol with some Ketones at three temperature
...Show More Authors

Publication Date
Sun Apr 08 2018
Journal Name
Al-khwarizmi Engineering Journal
Microstructural Characterization and Mechanical Properties of Similar and Dissimilar Al Alloys Joined using Friction Stir Welding
...Show More Authors

The influence of pre- shot peening and welding parameters on mechanical and metallurgical properties of dissimilar and similar aluminum alloys AA2024-T3 and AA6061-T6 joints using friction stir welding have been studied. In this work, numbers of plates were equipped from sheet alloys in dimensions (150*50*6) mm then some of them were exposed to shot peening process before friction stir welding using steel ball having diameter 1.25 mm for period of 15 minutes. FSW joints were manufactured from plates at three welding speeds (28, 40, 56 mm/min) and welding speed 40mm/min was chosen at a rotating speed of 1400 rpm for welding the dissimilar pre- shot plates. Tow joints were made at rotational speed of 1000 rpm and welding speed of 40m/min f

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Tue Oct 11 2022
Journal Name
College Of Islamic Sciences
Directing Grammarians for Grammatical Dispute To Interpret and Explain the fourth part of the Holy Qur’an
...Show More Authors

 

Abstract

 The miraculous of al-Quran has been surrounded by the attention of scholars, as it is the one that has astonished the rhetoricians with its eloquence. So , they paid attention to every part of it  and hugely they studied it with accuracy in respect to its Surah  ad Ayahs.   It is considered the most important source from which Arab scholars and early grammarians drew, given their unanimity that it is the highest degree of eloquence and the best record of the common literary language.

 

Among these sciences is the science of Grammar, and without Qur’an, this science would not have emerged, which later had control over every science of Arabic

... Show More
View Publication Preview PDF
Publication Date
Wed Dec 30 2015
Journal Name
College Of Islamic Sciences
The base does no harm And their impact on the employment contracts of Iraqi private universities
...Show More Authors

One of the rules concerning the control of civil transactions is the rule of no harm and harm, which was enacted by our Holy Prophet Muhammad (peace be upon him and his family). Scholars singled it out by research and investigation, and classified by non-scientists independent messages, showing the status of al-Qaeda in terms of its perception, meaning, branches and results, and the importance of this rule in the payment of damage and compensation for it has been provided by the Iraqi legislator generous within the provisions of Iraqi law in all its branches of public and private, as applied The judiciary Iraq The provisions of this rule have been issued and numerous decisions have been made to compensate for the damage and to give to ev

... Show More
View Publication Preview PDF