Enol-Keto tautomerism in 1-[(E)-1,3-benzothiazol-2-ylazo]naphthalen-2-ol has been studied using the B3LYP functional of density functional theory (DFT) with 6-31G(d,p) basis set. Relative and absolute energies, transition state geometries (TS), dipole moments, entropies, enthalpies and Gibbs free energies, equilibrium constants (KT) and rate of tautomerization (kr) were calculated. Also, the computations of geometries and vibration frequencies for the tautomers were calculated and compared. The results of the calculations showed that the enol form is the most stable form than other isomers, this might be due to intra-hydrogen bonding. The TS1 activation energies for tautomer A ↔ B, tautomer A ↔ C and tautomer B ↔ C are 92.65, 199.56 and 225.71 kJ/mol respectively. The TS1 is lower than TS2 by 102 kJ/mol, showing that A ↔ B and B ↔ C paths are thermodynamic control and A ↔ C path is a kinetic control. The overall calculated KT ≈ 1, indicating that all tautomers present in significant proportions.
We introduce in this paper, the notion of a 2-quasì-prime module as a generalization of quasi-prime module, we know that a module E over a ring R is called quasi-prime module, if (0) is quasi-prime submodule. Now, we say that a module E over ring R is a 2-quasi-prime module if (0) is 2-quasi-prime submodule, a proper submodule K of E is 2-quasi-prime submodule if whenever , and , then either or .
Many results about these kinds of modules are obtained and proved, also, we will give a characterization of these kinds of modules.
Let R be a commutative ring with 10 and M is a unitary R-module . In this paper , our aim is to continue studying 2-absorbing submodules which are introduced by A.Y. Darani and F. Soheilina . Many new properties and characterizations are given .
An R-module M is called a 2-regular module if every submodule N of M is 2-pure submodule, where a submodule N of M is 2-pure in M if for every ideal I of R, I2MN = I2N, [1]. This paper is a continuation of [1]. We give some conditions to characterize this class of modules, also many relationships with other related concepts are introduced.
Dysregulation of matrix metalloproteinases-9 (MMP-9) and tissue inhibitors of
matrix metalloproteinases-1 (TIMP-1) may contribute to the development of
cardiovascular diseases in type 2 diabetes mellitus (T2DM) patients. The aim of this
study was to determine the effects of chronic hyperglycemia on serum
concentrations of MMP-9 and TIMP-1of T2DM patients without dyslipidemia (one
of atherosclerosis risk factors) and with duration less than 5 years in comparison
with T2DM patients with dyslipidemia and with duration more than 10 years and
controls. Also to investigate if serum levels of MMP-9 and TIMP-1 could be
potential markers for early detection of the development of cardiovascular
complications in T2DM pati
The aqueous extract of milk thistle (Silybum marianum) leaves as a green corrosion inhibitor for AA7051 aluminum alloy in sodium hydroxide solution was investigated at a range of temperatures. Potentiodynamic polarization findings exhibit a mixed–type inhibitor with directly increased inhibition efficiency with the concentration of inhibitor. The adsorption of the inhibitor on aluminum alloy obeys Langmuir isotherm and the kinetic as well as thermodynamic parameters were measured and discussed.
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The impact of a Schiff base namely 2-((thiophen-2-ylmethylene)amino)benzenethiol to corrode mild steel in 1 M HCl resolved was evaluated using different weight loss technique and scanning electron microscopy (SEM).different weight measurements to expand that the 2-((thiophen-2-ylmethylene) amino) benzenethiol inhibits the corrosion of mild steel through adsorbing of top for mild steel and block the active locality. The inhibitive impacts of 2-((thiophen-2-ylmethylene)amino)benzenethiol increase with increasing concentration and decrease with increasing temperature. SEM to checking revealed that the alloy surface was quite unaffected and formed protective film on its surface. The investigated
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In the present study, 1-ethyl -3-methyllimidazolium acetate ionic liquid is introduced for extractive desulfurization of Iraqi kerosene (1622ppm) and compared with 1-ethyl -3- methyllimidazolium tetrafloroborate. The effect of ionic liquid/ fuel ratio (1/9, 1/4, 1/2), temperature (25, 30,40oC), stirring speed (300,450rpm) and time (10, 30, 90, 180, 360 min) were studied. Sulfur compound analysis was performed using X-Ray fluorescence. The ionic liquid with acetate anion (OAc) showed better performance than tetrafloborate (BF4). The maximum extraction efficiency was 32% achieved at 1/2 IL/Fuel and 40oC after 90min. The oxidation step using hydrogen peroxide (8ml/200ml), catalyzed by acetic acid (2ml) and followed by ionic liquid extraction h
... Show MoreBackground: Frozen shoulder affects 2-5% of the
general population, and around 10-30% of diabetic
patients. It affect mainly the non-dominant shoulder,
and has more incidence in patients with poor
glycemic control.
Objective: To detect the incidence of frozen
shoulder in type 2 diabetic patients attending the
Specialized Center for Endocrinology and Diabetes
in Baghdad.Patients and methods: One hundred
patients with frozen shoulder were included in the
study from a total number of 580 type 2 diabetics
over a period of six months. 70 patients were
females and 30 patient were males. All were
investigated for fasting blood
glucose and HbA1c.
Results: The non-dominant shoulder was
involved in
The crystal structures of a new polymorph and seven new derivatives of 2-(1-phenyl-1H-1,2,3-triazol-4-yl)pyridine have been characterized and examined along with three structures from the literature to identify trends in their intermolecular contact patterns and packing arrangements in order to develop an insight into the crystallization behaviour of this class of compound. Seven unique C-H...X contacts were identified in the structures and three of these are present in four or more structures, indicating that these are reliable supramolecular synthons. Analysis of the packing arrangements of the molecules using XPac identified two closely related supramolecular constructs that are present in eight of the 11 structures; in all cases, the st
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