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Are Narrow Line Seyfert 1 galaxies a special class of Active Galactic Nuclei?
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No. Due to their apparently extreme optical to X-ray properties, Narrow Line Seyfert 1s (NLSy1s) have been considered a special class of active galactic nuclei (AGN). Here, we summarize observational results from different groups to conclude that none of the characteristics that are typically used to define the NLSy1s as a distinct group – from the, nowadays called, Broad Line Seyfert 1s (BLSy1s) – is unique, nor ubiquitous of these particular sources, but shared by the whole Type 1 AGN. Historically, the NLSy1s have been distinguished from the BLSy1s by the narrow width of the broad Hb emission line. The upper limit on the full width at half maximum of this line is 2000kms−1 for NLSy1s, while in BLSy1s it can be of several thousands of kms−1. However, this border has been arbitrarily set and does not correspond to the change of any physical property. All observed parameters in Type 1 AGN cover continues ranges of values, which does not allow to infer the existence of two different kind of populations with FWHMHb,broad = 2000kms−1 as dividing point. We argue that the usage of this velocity limit to define samples of NLSy1s galaxies – as it is usually done in comparative studies –, together with the well known observational biases, naturally favors the selection of sources with low black hole masses and high Eddington ratios that are hosted by blue spiral galaxies. Therefore selection biases might be responsible for the reported differences between NLSy1 and BLSy1 sources.

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Publication Date
Tue Mar 08 2016
Journal Name
Ibn Al-haitham Jour. For Pure & Appl. Sci.
Synthesis, Characterization and Spectral Studies of Y(III), La(II) and Rh(III) Complexes with 2,4-dimethyl-6-(4-nitro-phenylazo)- Phenol
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Transition metal complexes of Y(III), La(III) and Rh(III) with azo dye 2,4-dimethyl-6- (4-nitro-phenylazo)-phenol derived from 4-nitroaniline and 2,4-dimethylphenol were synthesized. Characterization of these compounds has been done on the basis of elemental analysis, electronic data, FT-IR,UV-Vis and 1HNMR, as well as conductivity measurements. The nature of the complexes formed were studies following the mole ratio and continuous variation methods, Beer's law obeyed over a concentration range (1x10-4- 3x10-4). High molar absorbtivity of the complex solutions were observed. From the analytical data, the stoichiomerty of the complexes has been found to be 1:3 (Metal:ligand). On the basis of Physicochemical data octahedral geometries were as

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Publication Date
Wed May 19 2010
Journal Name
College Of Science – University Of Babylon
Synthesis and Characterisation of Cu(II) ,Co(II) ,Ni(II) and Zn(II) Complexes Derived from Acetylacetone and P–Amino benzoic acid
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Publication Date
Wed Feb 12 2025
Journal Name
Sciences Journal Of Physical Education
Use different means rehabilitative according some bio-kinematics variables and their impact on increasing range of motion for people with shoulder joint
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Publication Date
Sat Sep 23 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Direct Estimation for Approximation by Bernstein Polynomial by Using Ditzian-Totik and Average in L Ja,h11 p < oo Modulus of Smoothness
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The  purpose  of  the  paper  is  to  tind  the  degree  of  the approximation of a functions  f be bounded , measurable and defined

in  interval   [a,h]by  Bernstein  polynomial  in  LP    space  1 $ p < oo by

 

using Ditzian-Totik modulus  of smootlmess  and  k 1n  average modvlus of smoothness.

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Publication Date
Wed Mar 08 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Synthesis, Characterization and Spectral Studies of Y(III), La(II) and Rh(III) Complexes with 2,4-dimethyl-6-(4-nitro-phenylazo)Phenol .
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Transition metal complexes of Y(III), La(III) and Rh(III) with azo dye 2,4-dimethyl-6(4-nitro-phenylazo)-phenol derived from 4-nitroaniline and 2,4-dimethylphenol were synthesized. Characterization of these compounds has been done on the basis of elemental analysis, electronic data, FT-IR,UV-Vis and 1HNMR, as well as conductivity measurements. The nature of the complexes formed were studies following the mole ratio and continuous variation methods, Beer's law obeyed over a concentration range (1x10-4- 3x10-4). High molar absorbtivity of the complex solutions were observed. From the analytical data, the stoichiomerty of the complexes has been found to be 1:3 (Metal:ligand). On the basis of Physicochemical data octahedral geometries were a

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Publication Date
Wed Feb 12 2025
Journal Name
Journal Of Administration And Economics
Proposal to use the style of the slides in the estimation and forecasting Fertility rates in Iraq for the period 2012-2031
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It is often needed in demographic research to modern statistical tools are flexible and convenient to keep up with the type of data available in Iraq in terms of the passage of the country far from periods of war and economic sanctions and instability of the security for a period of time . So, This research aims to propose the use of style nonparametric splines as a substitute for some of the compounds of analysis within the model Lee-Carter your appreciation rate for fertility detailed variable response in Iraq than the period (1977 - 2011) , and then predict for the period (2012-2031). This goal was achieved using a style nonparametric decomposition of singular value vehicles using the main deltoid , and then estimate the effect of time-s

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Publication Date
Wed Feb 12 2025
Journal Name
Journal Of Physical Education
Proposed Exercises Using Flexible Resisters And Their Effect On Developing Strength Endurance And The Performance of Some Offensive Skills In Youth Basketball
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Publication Date
Thu Jun 25 2020
Journal Name
International Journal Of Drug Delivery Technology
The Effects of Salvia officinalis Gel as an Adjunct to Scaling and Root Planning in Patients with Periodontitis (Clinical and Immunological Study)
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Background: Phytotherapy is the usage of herbal species with medicinal properties for the management of various diseases. Gingivitis and periodontitis are diseases that involve the role of both the bacteria and the host immune response. Over the years, various researches have shown the importance of herbal products in the management of periodontal diseases. Aims of the study: To evaluate the efficacy of locally applied Salvia officinalis gel as adjunctive in the treatment of chronic periodontitis. Subjects and methods: Fourteen patients (10 males and 4 females) with chronic periodontitis were enrolled in the present study with total number of twenty-eight periodontal pockets utilizing a split mouth design, the pockets were divided i

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Publication Date
Wed Aug 31 2022
Journal Name
Al-kindy College Medical Journal
Assessment of Awareness And Knowledge among Medical Students Regarding Radiation Exposure from Common Diagnostic Imaging Procedures: Radiation exposure awareness among medical students
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Objective: to assess the awareness and knowledge of our medical students regarding dose levels of imaging procedures and radiation safety issues, and to conclude how the curriculum of clinical radiology in the college medical program impacts such knowledge.

Subjects and methods:  this is a cross-sectional study conducted among 150 medical students in Alkindy College of Medicine between January 2021 to July 2021, regardless of their age or gender. The study included six grades according to the year 2020-2021. A questionnaire consisting of 12 multiple-choice questions was conducted via an online survey using Google Forms. The questions were divided into two parts

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Publication Date
Sun Jun 01 2014
Journal Name
Baghdad Science Journal
The synergistic effect of Zeolites type (?) with chlorinated rubber as flame retardants for unsaturated polyester resin: Jalil R. Ugal| Zahraa Q. Mahdi
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In this work, the synergistic effect of chlorinated rubber (additive I),with zeolite 3A (additive II), zeolite 4A (additive III), and zeolite 5A (additive IV) in (1:1) weight percentage, on the flammability for unsaturated polyester resin was studied in the weight ratios for (3,7,10,13&15%) by preparing films of (130×130×3) mm in diameters. Three standard test methods used to measure were the flame retardation which are; ASTM: D-2863, ASTM: D- 635& ASTM: D-3014. Results obtained from these tests indicated that all of the additives were effective additive IV has the highest efficiency as a flame retardant.

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