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The spatial extent of polycyclic aromatic hydrocarbons emission in the Herbig star HD 179218
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Aim. We investigate, in the mid-infrared, the spatial properties of the polycyclic aromatic hydrocarbons (PAHs) emission in the disk of HD 179218, an intermediate-mass Herbig star at ~300 pc.

Methods. We obtained mid-infrared images in the PAH-1, PAH-2 and Si-6 filters centered at 8.6, 11.3, and 12.5 μm, and N-band low-resolution spectra using CanariCam on the 10-m Gran Telescopio Canarias (GTC). We compared the point spread function (PSF) profiles measured in the PAH filters to the profile derived in the Si-6 filter, where the thermal continuum emission dominates. We performed radiative transfer modeling of the spectral energy distribution (SED) and produced synthetic images in the three filters to investigate different spatial scenarios.

Results. Our data show that the disk emission is spatially resolved in the PAH-1 and PAH-2 filters, while unresolved in the Si-6 filter. Thanks to very good observing conditions, an average full width at half maximum (FWHM) of 0.232′′, 0.280′′ and 0.293′′ is measured in the three filters, respectively. Gaussian disk fitting and quadratic subtraction of the science and calibrator PSFs suggests a lower-limit characteristic angular diameter of the emission of ~100 mas, or ~30 au. The photometric and spectroscopic results are compatible with previous findings. Our radiative transfer (RT) modeling of the continuum suggests that the resolved emission should result from PAH molecules on the disk atmosphere being UV-excited by the central star. Simple geometrical models of the PAH component compared to the underlying continuum point to a PAH emission uniformly extended out to the physical limits of the disk model. Furthermore, our RT best model of the continuum requires a negative exponent of the surface density power-law, in contrast with earlier modeling pointing to a positive exponent.

Conclusions. We have spatially resolved – for the first time to our knowledge – the PAHs emission in the disk of HD 179218 and set constraints on its spatial extent. Based on spatial and spectroscopic considerations as well as on qualitative comparison with IRS 48 and HD 97048, we favor a scenario in which PAHs extend out to large radii across the flared disk surface and are at the same time predominantly in an ionized charge state due to the strong UV radiation field of the 180 L central star.

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Publication Date
Fri Nov 15 2024
Journal Name
Iraqi Journal Of Science
Spatial and Temporal Analysis of Severe Dust Storm in Iraq in May 2022
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Dust storms are a common ecological occurrence in many world‘s countries, mainly in dry and semi-dry parts. Dust storms tremendously influence human health, the environment, the climate, and numerous social aspects. In this paper, spatial and temporal analysis, metrological triggers, and trajectory, dust exporting areas of a severe dust storm that occurred in Iraq on May 16, 2022, were investigated. The dust storm's backward trajectory was determined using HYSPLIT model, which is then compared with MODIS and Meteosat satellite images. The weather is then analyzed using the NCEP/NCAR Reanalysis model, and the approximate area of these sources was determined using Landsat 8 satellite image classification method. The results revealed

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Publication Date
Sat Mar 01 2008
Journal Name
Iraqi Journal Of Physics
Smoothing of Image using adaptive Lowpass Spatial Filtering
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Lowpass spatial filters are adopted to match the noise statistics of the degradation seeking
good quality smoothed images. This study imply different size and shape of smoothing
windows. The study shows that using a window square frame shape gives good quality
smoothing and at the same time preserving a certain level of high frequency components in
comparsion with standard smoothing filters.

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Publication Date
Wed Dec 30 2020
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Detection and isolation of flavonoid and aromatic acid from Cynara scolymus different parts cultivated in iraq
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The target of this study was to study the natural phytochemical components of the head (capsule) of Cynara scolymus cultivated in Iraq. The head (capsule) of plant was extracted by maceration in70% ethanol for 72 hours, and fractioned by hexane, chloroform and ethyl acetate. Preliminary qualitative phytochemical screening was performed on the ethyl acetate fraction for capsule was revealed the presence of flavonoid and aromatic acids. These were examined by (high -performance liquid chromatography) (HPLC diodarray), (high- performance thin-layer chromatography)(HPTLC).

Flavonoids were isolated by preparative layer chromatography and aromatic acid was isolated by preparative high-

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Publication Date
Fri Sep 30 2022
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The extent of compliance with the Central Bank’s of Iraq instructions regarding the liquidation real estate allocation and its impact on the fairness of the financial statements : An applied research
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 The financial statements   must accurately, clearly and fairly present the financial situation and financial statements should be reliable as well. Pursuant to Board Decision No. (74)  2020, CBI obliges banks, according to the Banking Law No. (94) for the year 2004, Article (33) paragraph 2  concerning real estate owned from previous years and expropriated as a result debt settlement , to apply a real estate liquidation provision  at  a  rate of 20% for each property expropriated and at a rate of 100% for each year of delay up to (5) years  .also from  the significance of the issue of  real estates that become a property of   banks as a result of debt settlement and the pr

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Publication Date
Wed Feb 01 2017
Journal Name
Journal Of Economics And Administrative Sciences
Star model –model of organization design and reflections of its variables and dimensions of health performance on-filed study in medical city hospital
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Abstract

      The goal of current research to describe and diagnose the level of attention of doctors to design and regulatory dimensions, (strategic vision, organizational structure, organizational processes, business systems, personnel), and the performance of hospitals and dimensions, in six hospitals in medicine and selected a sample for research, as well as identify organizational design effect in the performance of hospitals and dimensions (efficiency, the development of human resources, patient satisfaction, achieve financial results, quality of health care).

 Research has focused in part theoretical on key variables to look organizational des

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Publication Date
Mon May 15 2023
Journal Name
Iraqi Journal Of Science
Optimal Spatial Distribution of Gasoline Stations in Baghdad Province Utilizing GIS Techniques
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Studying the spatially distribution pattern of fuel station in province of Baghdad
was done by utilizing GIS techniques which they are the most powerful tools for
design, display and analysis for the spatial data. Nearest Neighbor Analysis method
was applied for analyzing the spatial distributions of the fuel stations. Baghdad was
considered to be divided in to two main parts (outskirts of Baghdad and center of
Baghdad). The nearest neighbour for all parts of Baghdad indicates for the
distribution pattern is random and differs from place to another in randomly rate.

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Publication Date
Fri Mar 01 2024
Journal Name
Baghdad Science Journal
Spatial Distribution of Heavy Element in Erbil's Municipal Landfills by Using GIS
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Untreated municipal solid waste (MSW) release onto land is prevalent in developing countries. To reduce the high levels of harmful components in polluted soils, a proper evaluation of heavy metal concentrations in Erbil's Kani Qrzhala dump between August 2021 and February 2022 is required. The purpose of this research was to examine the impact of improper solid waste disposal on soil properties within a landfill by assessing the risks of contamination for eight heavy elements in two separate layers of the soil by using geoaccumulation index (I-geo) and pollution load index (PLI) supported. The ArcGIS software was employed to map the spatial distribution of heavy element pollution and potential ecological risks. The I-geo values in summe

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Publication Date
Mon Jan 30 2023
Journal Name
Iraqi Journal Of Science
Characteristics of Lead and Sulfur Plasma Parameters by Optical Emission Spectroscopy
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This study uses the optical emission spectroscopy (OES) technique to find the lead(Pb) and sulfur (S) plasma parameters employing a pulse of Nd: YAG laser (Q-switched 1064nm wavelength) and different laser energies of (400,500,600 and 700 mJ). The electron temperature Te (eV) is calculated using the Boltzmann-Plot method, and the electron density ne (cm-3)is determined by the Stark broadened way. Moreover, Debye length λD (cm) and plasma frequency ωp (Hz) are studied as a function of laser energy. An apparent increase was noted in the electron temperature of lead plasma and a decrease in sulfur plasma. The results also showed that each increase in the laser intensity causes an incr

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Publication Date
Tue Jan 01 2019
Journal Name
Technologies And Materials For Renewable Energy, Environment And Sustainability: Tmrees19gr
Characteristics measurement of Baghdad University radio telescope for hydrogen emission line
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The aim of this paper is to measure the characteristics properties of 3 m radio telescope that installed inside Baghdad University campus. The measurements of this study cover some of the fundamental parameters at 1.42 GHz. These parameters concentrated principally on, the system noise temperature, signal to noise ratio and sensitivity, half power beam width, aperture efficiency, and effective area. These parameters are estimated via different radio sources observation like Cas-A, full moon, sky background, and solar drift scan observations. From the results of these observations, these parameters are found to be approximately 64 K, 1.2, 0.9 Jansky, 3.7°, 0.54, and 3.8 m2 respectively. The parameters values have vital affect to quantitativ

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Publication Date
Sun Mar 01 2020
Journal Name
Iraqi Journal Of Physics
Effect of Laser Energy and Repetition Rate on Holmium Plasma Emission
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The holmium plasma induced by a 1064-nmQ-switched Nd:YAG laser in air was investigated. This work was done theoretically and experimentally.  Cowan code was used to get the emission spectra for different transition of the holmium target. In the experimental work, the evolution of the plasma was studied by acquiring spectral images at different laser pulse energies (600,650,700, 750, and 800 mJ). The repetition rates of (1Hz and 10Hz) in the UV region (200-400 nm). The results indicate that, the emission line intensities increase with increasing of the laser pulse energy and repetition rate. The strongest emission spectra appeared when the laser pulse energy is 800mJ and 10 Hz repetition rate at λ= 345.64nm, with the maximum intensi

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