A.C electrical conductivity and dielectric properties for poly
(vinyl alcohol) (PVA) /poly (ethylene oxide) (PEO) blends undoped
and doped with multi-walled carbon nanotube (MWCNTs) with
different concentrations (1, and 3 wt %) in the frequency range
(25x103 - 5x106 Hz) were investigated. Samples of (PVA/PEO)
blends undoped and doped with MWCNTs were prepared using
casting technique. The electrical conductivity measurements showed
that σA.C is frequency dependent and obey the relation σA.C =Aωs for
undoped and doped blends with 1% MWCNTs, while it is frequency
independent with increases of MWCNTs content to 3%. The
exponent s showed proceeding increase with the increase of PEO
ratio (≥50%) for undoped blends samples, while s value for doped
blends exhibits to change in different manner, i.e. s increases and
reach maximum value at 50/50 PVA/PEO, then decreases for
residual doped blends samples with 1% MWCNTs on the other hand
the exponent s decrease and reach minimum value at 50/50
PVA/PEO for samples doped with 3% MWCNTs, then return to
increase. The results explained in different terms.
The importance of Public Relations activity has increased during the last half of the last century as a specialized and modern administrative function in most institutions. It has, moreover, become an integral part of activities of those institutions of various types, due to its pivotal role in building its reputation and drawing a good mental image among its audiences, as well as its influential and basic role in maintaining communication and the communication between its members at its various levels and their job tasks to ensure the greatest amount of understanding and to enhance trust between them. This is why public relations activity has become indispensable in all institutions, and without it, it is difficult to achieve any coordi
... Show MoreHierarchical temporal memory (HTM) is a biomimetic sequence memory algorithm that holds promise for invariant representations of spatial and spatio-temporal inputs. This article presents a comprehensive neuromemristive crossbar architecture for the spatial pooler (SP) and the sparse distributed representation classifier, which are fundamental to the algorithm. There are several unique features in the proposed architecture that tightly link with the HTM algorithm. A memristor that is suitable for emulating the HTM synapses is identified and a new Z-window function is proposed. The architecture exploits the concept of synthetic synapses to enable potential synapses in the HTM. The crossbar for the SP avoids dark spots caused by unutil
... Show MoreComplexes of some metal ions with 2-thiotolylurea were prepared in ethanolic medium using (1:1) (Metal : Ligand) ratio yielded series of neutral complexes as the general formula [M(L)Cl2]. The prepared complexes were identified by atomic absorption FT.IR, UV-Visble spectra, molar conductivity and magnetic properties. From the above data the tetrahedral structure was suggested for all complexes.
In the present investigation, 24 adult dipteran species with forensic importance belonging to 13 genera and 8 families that were collected from different localities of Iraq. The specimens were identified by different taxonomical keys; in addition the date and localities of collecting specimens were recorded.
In this study, nanocomposites have been prepared by adding
multiwall carbon nanotubes (MWCNTs) with weight ratios (0, 2, 3,
4, 5) wt% to epoxy resin. The samples were prepared by hand lay-up
method. Influence of an applied load before and after immersion in
sodium hydroxide (NaOH) of normality (0.3N) for (15 days) at
laboratory temperature on wear rate of Ep/MWCNTs
nanocomposites was studied. The results showed that wear rate
increases with increasing the applied load for the as prepared and
immersed samples and after immersion. It was also found that epoxy
resin reinforced with MWCNTs has wear rate less than neat epoxy.
The sample (Ep + 5wt% of MWCNTs) has lower wear rate. The
immersion effect in base so
This research presents a numerical study to simulate the heat transfer by forced convection as a result of fluid flow inside channel’s with one-sided semicircular sections and fully filled with porous media. The study assumes that the fluid were Laminar , Steady , Incompressible and inlet Temperature was less than Isotherm temperature of a Semicircular sections .Finite difference techniques were used to present the governing equations (Momentum, Energy and Continuity). Elliptical Grid is Generated using Poisson’s equations . The Algebraic equations were solved numerically by using (LSOR (.This research studied the effect of changing the channel shapes on fluid flow and heat transfer in two cases ,the first: cha
... Show More4-[(2-hydroxy-4,6-dimethylphenyl)diazenyl]-1,5-dimethyl-2-phenyl-1H-pyrazol-3(2H)-one has been readied by combination the diazonium salt of 4-aminoantipyrine with 3,5-dimethylphenol. Spectral studies ( FTIR, UV-Vis, 1H and 13CNMR) and microelemental analysis (C.H.N) are use to identified of the ligand. Complexes of some transition metals were performed as well depicted. The formation of complexes were characterized by using atomic absorption of flame, elemental analysis, infrared and UV-Vis spectral process as well conductivity and magnetic quantifications. Nature of compounds produced have been studied followed the mole ratio and continuous contrast methods, Beer's law followed during a concentration scope (1×10-4 - 3×10-4 M/L). height m
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