In the beta decay process, a neutron converts into a proton, or vice versa, so the atom in this process changes to a more stable isobar. Bethe-Weizsäcker used a quasi-experimental formula in the present study to find the most stable isobar for isobaric groups of mass nuclides (A=165-175). In a group of isobars, there are two methods of calculating the most stable isobar. The most stable isobar represents the lowest parabola value by calculating the binding energy value (B.E) for each nuclide in this family, and then drawing these binding energy values as a function of the atomic number (Z) in order to obtain the mass parabolas, the second method is by calculating the atomic number value of the most stable isobar (ZA). The results show that the mass parabolas of isobar elements with an even mass number (A=even) vary from the mass parabolas of isobar elements with an odd mass number (A=odd), In the case of single isobars, it has one parabola, meaning that it has one stable isobar, while we find that the pairs isobars appear to have two parabolas, meaning that it has more than one stable isobar. When we compared the two methods used in this study to determine the most stable isobars, we found that in two techniques for odd isobars, stable isobars are mostly the same nuclide, whereas in suitcases of even isobars with two stable isobars (only one of them are same stable isobars).
Finding Most Stable Isobar for Nuclides with Mass
Number (165- 175) against Beta Decay
Binding Energy
Liquid Drop Model (LDM)
Bethe-Weizsäcker Semi Empirical Formula
Mass Parabolas
Isobaric Nuclides.
Publication Date
Tue Oct 01 2013
Journal Name
Journal Of Economics And Administrative Sciences
أثـر الأدوات الداخلية لحوكمة الشركة على رأس المال الـعـامـل وانعكاسهما علـى القيـمـة الاقتصـادية المضـافـة: دراســة تطبيقيـة علـى عينــة مـــن الشـركــات الصنــاعــيــة المـدرجــة في بورصــة عـمّــان لــلأوراق المـالـيـة
/ Corporate Governance Instrument- Net Working Capital- Economic Value Added- Weighted Average Cost of Capital- Capital Asset Pricing Model
أدوات حوكمة الشركات- صافي راس المال العامل- القيمة الاقتصادية المضافة- المتوسط الموزون لكلفة راس المال- نموذج تسعير الاصول الرأسمالية.
Abstract
Objective of this research focused on testing the impact of internal corporate governance instruments in the management of working capital and the reflection of each of them on the Firm performance. For this purpose, four main hypotheses was formulated, the first, pointed out its results to a significant effect for each of corporate major shareholders ownership and Board of Directors size on the net working capital and their association with a positive relation. The second, explained a significant effect of net working capital on the economic value added, and their link inverse relationship, while the third, explored a significant effect for each of the corporate major shareholders ownershi
... Show More
Publication Date
Sat Oct 01 2022
Journal Name
Environmental Advances
Stability and performance studies of emulsion liquid membrane on pesticides removal using mixture of Fe3O4Â nanoparticles and span80
The current study investigated the impact of nonionic surfactant span 80 in the existence of Fe3O4 magnetic nanoparticles on the emulsification of mixture of kerosene as petroleum based organic solvents and corn oil as a green diluent in the ratio 1:1
HCl was used as internal phase and the stability of the emulsion was carried out. The proposed Pickering emulsion liquid membrane has been exploited to investigate it is ability in the extraction of Abamectin pesticides from aqueous solution without utilizing carrier agent. Further
the effects of experimental parameters on extraction efficiency and emulsion stability such as
homogenizer speed
emulsification speed
contact time
Fe3O4-Span 80 ratios
HCL concentration
internal to membrane volume ratio (I/O) and pH of the external feed solution were carried out. The results showed that more than 99% of Abamectin could be extracted at 10 min contact time with a minimum breakage percent of 0.52% at the optimal conditions. The kinetic of the extraction were studied and the mass transfer coefficient was found to be for external phase () of 1.2
interfacial reaction rate constant () of 5.83 and the overall mass transfer coefficient () of 3.91 . The results of recyclability of the PELM revealed that the emulsion stability and extraction efficiency was nearly unchanged after three cycles.
(12)
(10)
Publication Date
Mon Nov 01 2010
Journal Name
Al-nahrain Journal Of Science
Chemical Elements Diffusion in the Solar Interior
The standard solar model and equation of state have been used to study relative diffusion of Hydrogen and Helium in the present time for solar interior
as a function of distance and depth from the center of the star. The effects of temperature and density on diffusion velocity for these chemical elements have been explaned.
It is found that heat flow which is arising from these reactions leads to an increase in helium diffusion velocity
while the temperature and density leading to a decrease in Hydrogen diffusion velocity. This means that Hydrogen behaves inversely with that for helium does through these reactions. Accordingly
diffusion percentages for Hydrogen
Helium and other Heavy Elements could be determined for the main sequence stars and white dwarf stars.
Publication Date
Mon Apr 06 2020
Journal Name
August
INFLUENCE OF SOME FACTOR ON SOMATIC EMBRYOS INDUCTION
AND GERMINATION OF DATE PALM CV BARHI BY USING CELL
SUSPENSION CULTURE TECHNIQUE
This study was done to examine different concentrations of mercuric chloride (Hgcl2) for Explants sterilization and different
concentration of NAA) mg/L with 2iP for their effect on initiation primary callus and subsequent embryogenesis in Phoenix
dactyliferae cultivar Barhi. Leaf primordial and shoot tips were excised from 2-3 years old offshoot. The result showed that
contamination percentage decreased with an increase in concentration of Hgcl2 for two explants where in the control (0.0)%
gave highest value 75% and 62.5% of contamination for leaf primordial and shoot tip respectively while the addition (0.1)%
gave a significant decrease 37.5 and 0% for explants respectively. The Explants were inoculated onto Murashiege and Skoog
1962 (MS) medium supplemented with 2iP 3mg/L and containing 0
25
50 or 100 mg/L of NAA
the addition (50) mg/L of NAA
gave highest value 68.8% in percentage of callus initiation with significant difference from addition 0% gave lowest value
(18.8)%
as well Explants of shoot tip gave significant difference was 53.1% while leaf primordial gave 28.1%
Primary callus
was transferred to fresh MS medium containing (0
5
10 and 20) mg/L of NAA with 3mg/L 2iP
Results were recorded after 12
weeks. A highest value of embryonic callus induction percentage or fresh weight and dry weight 87.5% or 1.56g and 0.47g for
the character respectively for the treat 20 mg/L while control treatment 0.0 gave the lowest value 12.5% or 0.37g and 0.14g for
same character respectively. Inoculated 1g fresh biomass into a 250 ml Erlenmeyer flask containing 50 ml MS liquid medium
supplemented with NAA 20mg/L and agitated at 150 rpm by shaker to making suspension culture the measurements of
packed cell volume ( pcv) or fresh and dry weight taken weekly for 12 weeks
maximum values were reached in the eighth week
of PCV and fresh weight but the dry weight reached to highest value in seventh week
then the curve began to decline
gradually until it reached stability in the last two weeks. The cell suspension was Diluted to different initial cell density of 100
500
10000
50000 and 100000 cells /ml with hemocytometer. The initial cell number of (10000) cells gave significant different
of plating efficiency PE (11.6)% while (100) cells gave lowest value 1.8% of PE.
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)
The 1
3-dipolar cycloaddition “click” reaction between an azide and an alkyne to give a 1
2
3-triazole was reported by Huisgen in 1961 [1]. In 2002 the Copper(I)-catalyzed Azide-Alkyne Cycloaddition (CuAAC) to prepare a 1
2
3-triazole was reported [2]
[3]. The existence of relatively basic nitrogen atoms in the 1
2
3-triazole rings
and the possibility of introducing additional donor groups in the substituents (Fig. 1)
made the CuAAC “click” reaction an attractive method to prepare differently substituted 1
2
3-triazoles. These compounds have been used as ligands to coordinate to various metal ions that display a range of applications such as in electrochemical and photochemical studies
in supramolecular chemistry
magnetism
metal-ion sensing and catalysis [4]. The reasons for the success of the “click” reaction
is that it is easy to carry out and is widely applicable. It is not affected by a variety of functional groups
and can be carried out with a variety of Cu(I) catalysts and solvents
including aqueous conditions. The Cu(I) catalysts overcome the high activation energy barrier of the non-catalyzed Huisgen reaction by changing the mechanism of the reaction. A large variety of copper catalysts can be used for the CuAAC reaction
on condition that the maximum concentration of Cu(I) species is generated during the reaction. The pre-catalyst can be a Cu(II) salt (usually CuSO4) together with a reducing agent (often sodium ascorbate) or a Cu(I) compound in the presence of a base or amine ligand and a reducing agent to prevent oxidation to Cu(II). Some strong oxidising cupric salts or complexes such as Cu(OAc)2 also work. The solvent is very flexible from organic to aqueous
with the most commonly used combination water + an alcohol (t-BuOH
MeOH or EtOH). The key role of the solvent or solvent mixture is to solubilize the substrates and Cu(I) catalyst in order to ensure rapid reactions. Such aqueous conditions are very useful for biochemical conjugations
as well as for organic syntheses.
We recently reported on the synthesis of a series of differently substituted 1
2
3-triazole chromophores
the substituted 2-(1-phenyl-1H-1
2
3-triazol-4-yl)pyridine ligands [5]
see Fig. 2 middle
with substituents R = H (L1)
CH3 (L2)
OCH3 (L3)
COOH
F
Cl
CN
CF3
O(CH2)3CH3 and N(CH3)2. These versatile ligands were found to coordinate to various first row transition metals
such as manganese
cobalt and nickel [6]. Here we extend the series to include more first row transition metal(II) coordination compounds
iron
copper and zinc
as well as a second row transition metal(II) coordination compound
cadmium
containing the 2-(1-(4-methyl-phenyl)-1H-1
2
3-triazol-1-yl)pyridine chromophore (Fig. 2 right with R = CH3). This series of seven novel coordination compounds is the first series of pyridyl-triazole based transition metal coordination compounds where seven different transition metals are coordinated to the same 1
2
3-triazole chromophore
namely 2-(1-(4-methyl-phenyl)-1H-1
2
3-triazol-1-yl)pyridine.