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UV-Exposure effect on the mechanical properties of PEO/PVA blends
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     Poly ethylene oxide PEO / Poly vinyl alcohol PVA  blends were prepared by cast method at different ratios of (25%PEO/75%PVA, 30%PEO/70%PVA, 35%PEO/65%PVA, 40%PEO/60%PVA, and 50%PEO/505PVA). Samples miscibility ,and thermal stability were studied  by using differential scanning calorimetry(DSC),and thermo gravimetric analysis (TGA) analysis. The results proved that there was one glass transition temperature (Tg=160°C) at 25%PEO\PVA ratio
)that was attributed to its miscibility. This miscibility associated with (Hydrogen  bonds) between (Hydroxyl group) in PVA, and PEO, whereas there were two glass transition temperature for the blends ratio more than 30%PEO,that was due its immiscibility. The results proved increase in glass transition temperature (Tg) with PEO loading increase: whereas the melting point was fixed about(Tm=310°C). TGA results showed that  PEO loading caused overlapping between degradation stages ,and shifting in the second stage to higher degradation temperature, that was due to the good  PVA, and PEO compatibility, and thermal  stability improved of polymer blends. The mechanical properties of the samples  involved were studied :it was found  that  the tensile strength decreased with PEO ratio increase: whereas ,the elongation at break increased  with PEO ratio . 25% PEO/PVA proved  better tensile strength than the others blend ratios and elongation-at-break values in comparison with that ratio more than 25%,which was due  to good miscibility. These results were enhanced with optical microscope and FTIR analysis. 25%PEO/PVA was sellected to  study the UV-Weathering effect on the mechanical properties according to its ultimate strength(26.67MPa) in comparision with the blends envolved.The stress strain curves for 25%PEO/PVA before and after UV-Weathering with periods of time(25,60,and 90Hr.) showed little changes in ultimate strength up  to (60Hr) exposure time,then there were little decrese in ultmate strength in(90Hr) exposure time . Ultimate tensile strength decrease was attributed to premature failur induced by polymer photo degradation. UV-Weathering caused yelowish of  exposed samples that was due to long chain conjugated polymer sequencesbond formation induced by oxidative  photo degradation . The results proved little changes within (60Hr),that was attributed to polymer stability.It was folowed by little changes in tensile strength and   the elongation at break decreased that was due to sample brittlence increase,which was induced  by irradiation ,that caused modulus of elasticity increase. It was experimentally observed that the value of thermal conductivity of (PVA= 0.099W/cm.K).The results proved decrease in thermal conductivity with PEO loading increase.

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Publication Date
Thu Oct 12 2017
Journal Name
Iraqi Journal Of Laser
A Comparative Evaluation of Post-Operative Pain and Function after Gingival Depigmentation Using 940 Nm Diode Laser And Conventional Bur Method: 6 Months Study
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The aim of the study was to evaluate the efficacy of diode laser (λ=940 nm) in the management of gingival hyperpigmentation compared to the conventional bur method. Materials and methods: Eighteen patients with gingival hyperpigmentation were selected for the study with an age between 12-37 years old. The site of treatment was the upper gingiva using diode laser for the right half and the conventional method for the left half. All patients were re-evaluated after the following intervals: 3 days, 7 days, 1 month and 6 months post-operation. Pain and functions were re-evaluated in each visit for a period of 1 day, 3 days and 1 week post-operation. Laser parameters included 1.5 W in continuous mode with an initiated tip (400 μm) placed in

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Publication Date
Wed Dec 30 2020
Journal Name
Al-kindy College Medical Journal
Effectiveness of conventional phototherapy, intensive phototherapy and exchange transfusion in treating neonatal jaundice at Fatima Al-Zahra Hospital for maternity and children in Baghdad
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Background: Neonatal hyperbilirubinemia is a common disease in neonates especially in early days of birth that requires a good and successful treatment for reducing the severity and its complications that can produce important and irreversible effects.

Objectives: To evaluate the effectiveness of conventional phototherapy, intensive phototherapy and exchange transfusion on outcomes of neonatal jaundice at Fatima Al-Zahra Hospital for maternity and child care in Baghdad.

Patients & Methods: A retrospective study was carried out using medical records of neonates with diagnosis of unconjugated jaundice, admitted in the septic neonatal care unit of Fatima Al-Zahra hospital over 6 months period b

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Publication Date
Sun Jan 01 2012
Journal Name
Natural Science
Determination of threshold random gain medium in dye: Polymer films containing TiO<sub>2</sub> nanoparticles
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Publication Date
Fri Jan 10 2025
Journal Name
Journal Of Baghdad College Of Dentistry
An Evaluation of Corrosion Pits in Esthetic Coated Stainless Steel Orthodontic Archwires in Dry and Wet Environment at Different Intervals (An In Vitro Study)
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Background: The demand for esthetic orthodontic appliances is increasing; so the esthetic orthodontic archwires were introduced. Among them, Teflon and Epoxy coated stainless steel archwires. The amount of force available from the archwire depends on the structural properties and susceptibility to corrosion. All metallic alloys are changed during immersion in artificial saliva, chlorhexidine mouthwash andtoothpaste, but their behaviors differ from one type to another. They corrode at different rates, which lead to decrease the amount of force applied to the teeth. This in vitro study was designed to evaluate the corrosion pits in stainless steel archwires coated with Teflon and with Epoxy in dry and after immersion in artificial saliva, chl

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Publication Date
Sun Dec 27 2020
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Isolation, Structural Characterization and Identification of Major Constituents in Ephedra foliata Naturally Growing in Iraq by TLC, GC-MS and UPLC-ESI-MS/MS
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Abstract:

   The aerial part of Ephedra foliata Family Ephedraceae have long been used in traditional medicine and now Ephedra species have medicinal, ecological, and commercial value. The variety of pharmacological actions of this plant is due to its chemical constituents. Ephedrine and
related alkaloids; are the newly potential medicinal value of Ephedra supplements for weight loss or performance improvement. Other pharmacological actions like antibacterial and antifungal effects of the phenolic acid compounds, the immunosuppressive action of the polysaccharides, and the antitumor action of flavonoids. The genus of this plant wildly distributed t

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Publication Date
Fri Jan 01 2016
Journal Name
Journal Of The College Of Languages (jcl)
ARZI KANBER HİKAYESİ'NİN IRAK TÜRKMENLERİ ARASINDA TESPİT EDİLEN YENİ BİR VARYANTI'NIN İNCELENMESİ ANALYZING A NEW TEXT OF " ARZO AND QENBER "TALE AMONG IRAQI TURKMENS
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Öz      

            Arzı Kanber/Kamber hikayesi Anadolu, Rumeli, Azerbaycan, Türkmenistan ve Irak gibi Türk dünyasının birçok yerinde birden fazla varyantı bulunan, çok sevilen ve yaygın olarak anlatılan aşk ve dramatik maceralı bir halk hikayesidir. Türk halk hikayelerinin en popüler olanlarından biri sayılan Arzı Kanber/Kamber hikayesi, Anadolu'nun birçok yöresinde bilinmesine rağmen Irak Türkmenleri arasında daha çok sevildiği ve yaygın olarak anlatıldığı tespit edilen birden fazla varyantından da görülebilir. Irak Türkmenleri arasında günümüze kadar hikayenin iki varyantı tespit edilmi

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Publication Date
Sun Jun 30 2013
Journal Name
Al-kindy College Medical Journal
Measuring Lower Uterine Segment Thickness Using Abdominal Ultrasound to Predict Timing of Cesarean Section in Women with Scarred Uterus at Elwiya Maternity Teaching Hospital
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Background: Ultrasonography has been used to examine the thickness of the lower uterine segment in women with previous cesarean sections in an attempt to predict the risk of scar dehiscence during subsequent pregnancy. The predictive value of such measurement has not been adequately assessed. Objectives: To correlate lower uterine segment thickness measured by trans abdominal ultrasound in pregnant women with previous cesarean section with that measured during cesarean section by caliper and to find out minimum lower uterine segment thickness indicative of integrity of the scar.Methods: A prospective observational study at Elwyia Maternity Teaching Hospital, from January 2011 to January 2012. A total of 143 women were enrolled in the stu

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Publication Date
Wed May 07 2008
Journal Name
Journal Of Kerbala University
Synthesis and Characterization of New Ligand type N2O2 and its complexes with (Co(II),Ni(II),Cu(II),Zn(II) and Cd(II) ions
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The [2-hydroxy -1,2-diphynel-ethanone oxime] was reacted with 1,2- dichloroethan to give the new ligand [H2L].this ligand was reacted with some metal ions (Co(II),Ni(II),Cu(II),Zn(II) and Cd(II) in methanol as a solvent to give a series of new (1:1)complexes of the general formula [ M(HL)]Cl ,( where : M= Co(II),Ni(II),Cu(II),Zn(II) and Cd(II)) are isolated All compounds have been characterized by spectroscopic methods [ I.R , U.V -Vis ] atomic absorption . Chloride content along with conductivity measurements. From the above data the proposed molecular structure for (Co, Cu, Ni, Zn and Cd) complexes adopting a tetrahedral structure.

Publication Date
Fri Feb 01 2019
Journal Name
Journal Of Pharmaceutical Sciences And Research
Synthesis of some Schiff base metal complexes involving trimethoprim and 2'-amino-4-chlorobenzophenone: Spectral, thermal, DNA Cleavage antimicrobial,antifungal and Cytotoxic activity studies
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In study of effective bioactive compounds, we have synthesized the Co((ІІ), Mn(ІІ), Fe(ІІ), Cu(ІІ), Ni(ІІ), and Zn(ІІ) complexes of the Schiff base derived from trimethoprim and2'-amino-4-chlorobenzophenone and characterized by spectroscopic (NMR, IR, Mass, UV–vis,), analytical, TGA studies and magnetic data .The solution electronic spectral study suggests the stoichiometry of the synthesized complexes and Elemental analysis detected the square planer and octahedral geometry of the compounds. The prepared metal complexes presented promoted efficiency versus the screened bacterial (Escherichia Coli and Staphylococcus aureus) antibacterial efficacy against (Staphylococcus aureus, Salmonella spp., E. coli, Vibrio spp., Pseud

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Publication Date
Tue Jul 28 2020
Journal Name
Iraqi Journal Of Science
Charge Transfer Spectrophotometric Determination of Metronidazole in Pharmaceutical Formulations by Normal and Reverse Flow Injection Analysis Coupled with Solid-Phase Reactor Containing Immobilized FePO4
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     Two rapid, simpleand sensitive flow injection methods were developed for the estimation of metronidazole (MRZ) in pharmaceutical formulations. The proposed methods were based on charge transfer reaction between metol (N-methyl-p-aminophenol sulfate) as a Ï€-acceptorand reduced MRZ as an n-donor to produce a blue colored chargetransfer complex. Method A depends on the reaction of reduced MRZ with metol (MT) in the presence of NaIO4 using two lines manifold to form blue colored product exhibiting absorption maxima at 700 nm.While method B depends on charge transfer reaction of reduced MRZ with MT in presence of a solid phase reactorcontainingfixedFePO4 on cellulose acetateusing reverse flow

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