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The Causes Influencing the Occurrence of Variation Orders in the Construction of Buildings
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In the construction of buildings usually, problems occur because of the causes of change orders. The main causer of change orders is the owners, consultants, and contractors. These changes lead to conflicts among them which result in influencing building projects. Therefore, it is necessary to analyze the causes of change orders to reduce them and facilitate management. This paper determines the most critical factors that cause change orders from a different point of view, a consulting owner and a contractor, and a study of the reality of the management of change orders when constructing public buildings. The method employed in this research is a field survey using interviews with experts working in the construction of public buildings. Furthermore, the questionnaire was distributed manually and electronically.

In conclusion, it would appear that the causes of change orders have been hierarchically according to the viewpoint of the owner, contractor, and consultant. The analysis leads to the following conclusions: Agreement of viewpoints owners, contractors, and consultants on the critical causes of variation orders were: ( the difficult financial situation - change material specifications to benefit the project - technical necessity  - the nature of the site). Moreover, the point of view (owners and contractors) on the essential factors that cause change orders were: (preparing a bill of quantities is inaccurate - weak consultant guess ). In contrast, the consultant's point of view differs, as he considers these causes ineffective. It can be interpreted that the consultant sees these factors as insignificant because of his duty to implement the bill of quantities and designs. This research paper concludes that a complex causal relationship exists between the causes of change orders. The relative importance index (RII) for variation order causes varies among different groups' viewpoints (owners, contractors, and consultants).

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Publication Date
Fri Dec 01 2023
Journal Name
Case Studies In Chemical And Environmental Engineering
Removal of copper from a simulated wastewater by electromembrane extraction technique using a novel electrolytic cell provided with a flat polypropylene membrane infused with 1-octanol and DEHP as a carrier
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Publication Date
Sat Jan 01 2022
Journal Name
Egyptian Journal Of Chemistry
Structural, Characterization and Biological Activity of New Ligand N-(Pyrimidin-2-Yl Carbamothioyl) Acetamide and Its Complexes With (VO(II), Mn (II), Cu (II), Zn (II), Cd (II) and Hg (II)
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New ligand of N-(pyrimidin-2-yl carbamothioyl)acetamide was synthesized and its complexes with (VO(II), Mn (II), Cu (II), Zn (II), Cd (II) and Hg (II) are formed with confirmation of their structures on the bases of spectroscopic analyses. Antimicrobial activity of new complexes are studied against Gram positive S. aureus and Gram negative E. coli, Proteus, Pseudomonas. The octahedral geometrical structures are proved depending on the outcomes from the preceding procedures. Keywords: pyrimidin-2-amine, acetyl isothiocyanate, complexes, Antimicrobial activity

Publication Date
Tue Jun 07 2022
Journal Name
Egyptian Journal Of Chemistry
Structural, characterization and biological activity of new ligand N-(pyrimidin-2-yl carbamothioyl) acetamide and its complexes with (VO(II), Mn (II), Cu (II), Zn (II), Cd (II) and Hg (II)
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New ligand of N-(pyrimidin-2-yl carbamothioyl)acetamide was synthesized and its complexes with (VO(II), Mn (II), Cu (II), Zn (II), Cd (II) and Hg (II) are formed with confirmation of their structures on the bases of spectroscopic analyses. Antimicrobial activity of new complexes are studied against Gram positive S. aureus and Gram negative E. coli, Proteus, Pseudomonas. The octahedral geometrical structures are proved depending on the outcomes from the preceding procedures

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Publication Date
Sun Mar 04 2018
Journal Name
Iraqi Journal Of Science
Assessment of ISNAG fluorimeter (Total fluorescence measurements at+ 90° & - 90° using four solar cell on each side for 100mm distance at 2mm path length) with well-known fluorescent molecules via CFIA
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Two well-known fluorescent molecules: fluorescein sodium salt (FSS) and 2,7-dichloro fluorescein (DCF) were tried to prove the efficiency, trustability and repeatability of ISNAG fluorimeter by using discrete and continuous flow injection analysis modes.A linear range of 0.002-1 mmol/L for FSS and 0.003-0.7 mmol/L was for DCF, with LOD 0.0018 mmol/L and 0.002 mmol/L for FSS and DCF respectively, were obtained for discrete mode of analysis. While the continuous mode gave a linear range of 0.002-0.7 mmol/L and 0.003-0.5 mmol/L for FSS and DCF respectively, the LOD were 0.0016mmol/L and 0.0018 mmol/L for FSS and DCF respectively. The results were compared with classical method at variable λex for both fluorescent molecules at 95

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Publication Date
Thu Apr 01 2021
Journal Name
Chaos, Solitons & Fractals
Modeling and analysis of an <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si7.svg"><mml:mrow><mml:mi>S</mml:mi><mml:msub><mml:mi>I</mml:mi><mml:mn>1</mml:mn></mml:msub><mml:msub><mml:mi>I</mml:mi><mml:mn>2</mml:mn></mml:msub><mml:mi>R</mml:mi></mml:mrow></mml:math> epidemic model with nonlinear incidence and general recovery functions of <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" altimg="si8.svg"><mml:msub><mml:mi>I</mml:mi><mml:mn>1</mml:mn></mml:msub></mml:math>
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Publication Date
Fri Oct 24 2014
Journal Name
Journal Of Chemical And Pharmaceutical Research
Synthesis, characterization and antimicrobial activities of [Fe(II), Co(II), Ni(II),Cu(II) and Zn(II)] mixed ligand complexes schiff base derived from amoxicillin drug and 4-(dimethylamino)benzaldehyde with nicotinamide
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New Schiff base ligand (E)-6-(2-(4-(dimethylamino)benzylideneamino)-2-(4-hydroxyphenyl)acetamido)-3,3- dimethyl-7-oxo-4-thia-1- azabicyclo[3.2.0]heptane-2-carboxylic acid = (HL) was synthesized via condensation of Amoxicillin and 4(dimethylamino)benzaldehyde in methanol. Figure -1 Polydentate mixed ligand complexes were obtained from 1:1:2 molar ratio reactions with metal ions and HL, 2NA on reaction with MCl2 .nH2O salt yields complexes corresponding to the formulas [M(L)(NA)2Cl],where M=Fe(II),Co(II),Ni(II),Cu(II),and Zn(II), A=nicotinamide .

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Publication Date
Sat Jun 03 2023
Journal Name
Iraqi Journal Of Science
Effect Effect Effect Effect Effect Effect Effect of Thickness on Some Physical PropertiesThickness on Some Physical PropertiesThickness on Some Physical PropertiesThickness on Some Physical PropertiesThickness on Some Physical Properties Thickness on Some
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The effect of thickness variation on some physical properties of hematite α-Fe2O3 thin films was investigated. An Fe2O3 bulk in the form of pellet was prepared by cold pressing of Fe2O3 powder with subsequent sintering at 800 . Thin films with various thicknesses were obtained on glass substrates by pulsed laser deposition technique. The films properties were characterized by XRD, and FT-IR. The deposited iron oxide thin films showed a single hematite phase with polycrystalline rhombohedral crystal structure .The thickness of films were estimated by using spectrometer to be (185-232) nm. Using Debye Scherrerś formula, the average grain size for the samples was found to be (18-32) nm. Atomic force microscopy indicated that the films had

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Publication Date
Wed Jul 01 2020
Journal Name
International Journal Of Pharmaceutical Research
Synthesis and identification of some new N-substituted quinazoline-4-one, thiazine-4-one and tetrazoline rings incorporating N-ethyl-2-(benzylthio)benzimidazole acetate and study their application as anti-oxidant agent
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Publication Date
Sat Sep 23 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Synthesis and Characterization of New ligand ' ((2-{1..,[(2-hyd_roxy;..benzyli_dene)-hydrazono]- ethyl} benzen_e-l, 3, s--moll and ItComplexes W·itll. (Mn.(11 Fe(n), Cd<11J, a-nd Hg(n).) Tons
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Publication Date
Sat Sep 01 2018
Journal Name
Polyhedron
Novel dichloro (bis {2-[1-(4-methylphenyl)-1H-1, 2, 3-triazol-4-yl-κN3] pyridine-κN}) metal (II) coordination compounds of seven transition metals (Mn, Fe, Co, Ni, Cu, Zn and Cd)
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