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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
Tue Jul 11 2023
Journal Name
Journal Of Educational And Psychological Researches
The Effect of The Round Robin Strategy in Logical Thinking the Fourth in Chemistry
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The study aims to identify the impact of the round-robin strategy on the logical thinking of fourth-year middle school students in chemistry. Two groups were employed:  an experimental group consisted of (30) students who were taught according to the round-robin strategy, and the control group consisted of (30) students who were taught according to the traditional method. The researcher adopted the experimental design with partial control by preparing the visual thinking test tool, which consists of (20) multiple-choice items, it was applied as a post-test on the research sample. The result showed that there was a statistically significant difference in favor of the experimental group, which was taught according to the Round Robin s

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Publication Date
Tue Sep 19 2017
Journal Name
Al-academy
The structure of design and technology in the contemporary design in the interior spaces
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The design of the interior spaces process the product of intellectual civilization expresses the prevailing thought, discoverers of principles and beliefs through the sheen reflects the present, and generating languages ​​graphical variety caused a different revolution in design mounting structure, and because of the complex nature of the interior spaces were and we have to be a reflection of cultural reality of being a form of cultural expression and true embodiment of scientific developments prevailing for each stage where she was born, the changes occurring in human thought and then extremism and the discrepancy tastes among individuals all communities factors have caused a change in the design structure involving modernization an

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Publication Date
Wed Mar 10 2021
Journal Name
Baghdad Science Journal
DIFFICULTIES IN USING THE INTERNET IN THE TEACHING OF SCIENCES
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The present research aims at recognizing the difficulties and problems which hamper teachers and educators alike when using the internet for educational purposes.It discusses the benefits of the internet as a source of information or publication and as a communicative tool.Arandom sample of (30) teachers working at schools in Baghdad / Second Risafa,was selected.Three of the sample members use the internet for student project plans via internet centers, whereas 16 of them use it for chatting, emailing and research purposes.The rest of the sample have limited knowledge of the internet. The researcher used the interviewing method to gather data from

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Publication Date
Fri Jan 01 2016
Journal Name
Al–bahith Al–a'alami
Dictionaries in the News.. In the light of Semiotic analysis,
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We refer in this research into linguistic binaries, try rounding of simiaei news analysis. It is known that there are branches of Linguistics called social Linguistics, divided into communicative Linguistics and media. Perhaps the best justification for the inclusion of a new curriculum in media studies is a semiotic analysis of the news. I›ve turned the speech, language and communication studies in relation to different disciplines, many research projects, and returned only old curriculum, speed shift in thought, proportional to the revolution in information and communication technology, for reality imposed on the entire world, researchers are the first affected by this enormous humanitarian Almanza. Alsimiaaeon still shy away from an

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Publication Date
Sun Dec 01 2013
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The impact of the strengths and weaknesses in Iraqi newspapers: The evolution of the consumer - the reader
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The first section of this research discussed  the manner of the research from many sides like the problem it faces, importance of it , its targets ,boundaries, the way to collect and get information's and its assumption.

When the second chapter discussed the press – manufacturing and the development ,importance and types of newspapers, also its merits and weaknesses.

The third chapter talked about the scientific side and how to choose an assumption for the research . as it talked also about the apparent honest and stability tests that help in analyzing the research until getting results and so the right assumption for  the research will be chosen.

And finally, the fourth chapter put highlight on the be

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Publication Date
Wed Jun 01 2022
Journal Name
Political Sciences Journal
The nature of the relationship between the states and the union in the United States of America
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Knowing the nature of the relationship in federal systems lies in studying the political, social, economic and cultural forces, for their role in laying the foundations and the federal system. No matter how important the pillars of that system are, and through this research, we will learn how the political elites were able to crystallize this unique system, until it became one of the political systems that some countries seek to copy and apply its experience.

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Publication Date
Sun Oct 07 2012
Journal Name
Journal Of Educational And Psychological Researches
The Participation of the Students of the Colleges of Education in the Iraqi Universities in Literacy and Adult Education in Iraq. The Students of the Departments of Holy Quran and Islamic Education (A model)
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The study focuses on the problem that Iraq is approaching an increasing rate of literacy;the available data refers to a rate of (18% -19%). In addition to the fact that the generalcurrent role of the programs directed to literacy is not actually effective enough to limit the expansion of this rate.

The importance of this study highlights the fact that the Iraqi universities are an important tributary among the tributaries of human development, especially in spreading the education of the voluntary work in literacy field and confirming the connection between the students and their society and their role in solving one of the prominent challenges that face the development, i.e., literacy.

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Publication Date
Sat Mar 30 2013
Journal Name
College Of Islamic Sciences
 The responses of the army overseer to the grammarians in the preposition section
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This is a contextual study in face and isotope science, and I have made it in one of the terms faces and isotopes, which is the word (bad). Quranic also, and that is at every aspect they mentioned.
The nature of the research required that it be divided into three sections:
The first topic: I singled it out to show the types of contextual connotations.
- The second topic: I singled it out to define the word bad and its meaning.
- The third topic: I devoted it to the study of the word bad and explaining the significance of the Quranic context on the additional meaning and the original meaning.
Conclusion: It mentioned the most important results, which are:
1- The significance of the Quranic context is one of the most impo

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Publication Date
Sat Oct 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
The use of standard rates in the test of the financial stability for the banking sector in Iraq For the period 2009-2013
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ABSTRACT

The research focuses on the key issue concerning the use of the best ways to test the financial stability in the banking sector, considering that financial stability cannot be achieved unless  the financial sector in general and the banking sector  in particular are able to perform its key role in addressing the economic and social development requirements, under the laws and regulations that control  banking sector , as the only way that increases its ability to deal with any risks or negative effects experienced by banks and other financial institutions. The research goal is  to evaluate the stability of the banking system in Iraq, through the use of a set of econometrics an

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Crossref
Publication Date
Sat Oct 28 2017
Journal Name
The Emirates Journal For Engineering Research (ejer), Issn: 1022-9892
The theory of sustainable integral design: Integration in the sustainability of the Marshes in southern Iraq
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