This work describes the effect of temperature on the phase transformation of titanium dioxide (TiO2) prepared using metal organic precursors as starting materials. X-ray diffraction (XRD) was used to investigate the structural properties of TiO2 gels calcined at different temperatures (300, 500, 700) ?C. the results showed that the samples have typical peaks of TiO2 polycrystalline brookite nanopowders after calcined at (300 ?C), which confirmed by (111), (121), (200), (012), (131), (220), (040), (231), (132) and (232) diffraction peaks. Also, XRD diffraction spectra showed the presence of crystallites of anatase with low proportion of rutile phase where calcined at (500 ?C), while rutile phase domains at (700 ?C). The crystallite size of TiO2 nanopowders was calculated by Scherer's formula and showed that the crystallite size decreased and then increased with increasing the annealing temperature.
The research has conducted on shelterbelt of Al-Ashraf Najaf city to explore suitability of four Eucalyptus camaldulensis Dehnh. Forms and two other tree species; Casuarina equisetifolia and Olea europaea to the local dominant sever conditions. Development in growth was studied through the interval of five years. Growth parameters included height, DBH stem diameter, main stem height, crown diameter, and stem girth were investigated. Distance from water supply was inspected, too. Results showed superiority of E. camaldulensis upon other species. Investigations showed weakness in growth of C. equisetifolia where most of trees could not resist because of their position in oppos
... Show MoreBackground: Corona virus disease 2019 (COVID-19) is a communicable disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). It was first identified in December 2019 in Wuhan, China, and has since spread globally, leading to an ongoing pandemic.
Aim of study: to review the clinical, lab investigation and imaging techniques, in pediatric age group affected COVID-19 to help medical experts better understand and supply timely diagnosis and treatment.
Subjects and methods: this study is a retrospective descriptive clinical study. The medical records of patients were analyzed. Information’s recorded include demographic data, exposure history, symptoms, signs, laboratory findin
... Show Moreترجمۀ شعر به آهنگ موسیقی از شاهکارهای فکری که تولیدی علمی ترجمی می آراید به شمار میرود ، چیزی مورد نا راحتی ونومیدی نسبت به مترجم وجود ندارد ، اگر وی در این راه با تلاش کردنی سیر می رود تا ثمره های آن ترجمه می چیند .
روش پژوهشگر در آنچه از ترجمۀ ابیات شعر فارسی بر آمد ، روشی نوینی می داند که آن بر هماهنگی آواز الفاظ با یکدیگر اتکای می کند تا ترجمه دارای آوازی وهماهنگی ، به مرتبه ای موسیق
... Show MoreThis research involves design and simulation of GaussianFSK transmitter in UHF band using direct modulation of ΣΔ fractional-N synthesizer with the following specifications:
Frequency range (869.9– 900.4) MHz, data rate 150kbps, channel spacing (500 kHz), Switching time 1 µs, & phase noise @10 kHz = -85dBc.
New circuit techniques have been sought to allow increased integration of radio transmitters and receivers, along with new radio architectures that take advantage of such techniques. Characteristics such as low power operation, small size, and low cost have become the dominant design criteria by which these systems are judged.
A direct modulation by ΣΔ fractional-N synthesizer is proposed
... Show MoreTwo‐dimensional buoyancy‐induced flow and heat transfer inside a square enclosure partially occupied by copper metallic foam subjected to a symmetric side cooling and constant heat flux bottom heating was tested numerically. Finite Element Method was employed to solve the governing partial differential equations of the flow field and the Local Thermal Equilibrium model was used for the energy equation. The system boundaries were defined as lower heated wall by constant heat flux, cooled lateral walls, and insulated top wall. The three parameters elected to conduct the study are heater length (7 ≤
The study aims to select suitable ornamental plant species that can survive relatively with high concentrations of acetaminophen and methylparaben in constructed wetlands. Alternanthera spp, Asparagus aethiopicus and Chlorophytum comosum are examined to withstand three initial concentrations, 20, 100 and 200 mg/L of acetaminophen and methylparaben. A total of 21 plastic pails with each 3 L capacity consisting of nine pails are used for each pharmaceutical and personal care products (PPCPs) compounds (acetaminophen and methylparaben) for three ornamental plants (Alternanthera spp, Asparagus aethiopicus and Chlorophytum comosum), with three pails as plant controls. The results reveales
... Show MoreBackground: Antibacterial action of root canal filling is an important factor for successful root canal treatment, so the aim of the study was to identify and to compare the antimicrobial effect of new sealer (GuttaFlow) to commonly used endodontic sealers (AH Plus, Apexit and EndoFill) against four endodontic microbes. Materials and methods: Twenty patients aged (30-40) years with infected root canals were selected. Four types of microorganisms were isolated from root canals (E faecalis, Staphylococcus aureus, E coli and Candida albicans) and cultured on Mueller Hinton agar Petri-dishes. After identification and isolation of bacterial species, agar diffusion method was used to assess the antibacterial action of four contemporary endodontic
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Mixed convection heat transfer to air inside an enclosure is investigated experimentally. The bottom wall of the enclosure is maintained at higher temperature than that of the top wall which keeps in oscillation motion, whereas the left and right walls are well insulated. The differential temperature of the bottom and top walls changed several times in order to accurately characterize the temperature distribution over a considerable range of Richardson number. Adjustable aspect ratio box was built as a test rig to determine the effects of Richardson number and aspect ratio on the flow behavior of the air inside the enclosure. The flow fields and the average Nusselt number profiles were presented in this wo
... Show MoreThe inflammatory reactions cause nasal polyposes (NPs), which contained the paranasal sinuses and the nasal mucous membrane. They consist of recurrent multiple masses originating in the paranasal sinuses then spread from the middle meatus to the nasals cavity, which leads to the nasal blockage that causes the restriction of airflow to the olfactory area. This study aims at clarifying the role of IL-12RB2 polymorphism by using PCR technology in nasal mucosal stem cells in nasal polyps of Iraqi patients and use it as a biomarker. Fifty-eight cases of this study are referred to as nasal surgery, which selected from Dept.of Otolaryngology, Baghdad City, Iraq from May 2013 to January 2014. They were grouped into Control group (022 samples
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