In this work, functionally graded materials were synthesized by centrifugal technique at different
volume fractions 0.5, 1, 1.5, and 2% Vf with a rotation speed of 1200 rpm and a constant rotation time, T
= 6 min . The mechanical properties were characterized to study the graded and non-graded nanocomposites
and the pure epoxy material. The mechanical tests showed that graded and non-graded added alumina
(Al2O3) nanoparticles enhanced the effect more than pure epoxy. The maximum difference in impact strength
occurred at (FGM), which was loaded from the rich side of the nano-alumina where the maximum value was
at 1% Vf by 133.33% of the sample epoxy side. The flexural strength and Young modulus of the fu
Series of new complexes of the type [M2 (L)Cl4 ] are prepared from the new ligand[N1 ,N4 -bis(benzo[d]thiazol-2- yl)succinamide (L) derived from ethan-1,2-dicarbonyl chloride and 2-aminobenzothiozole,where, M= Ni(ii), Cu(ii) and Zn(ii) alsocomplexes of mix-ligands, the type [M(L)(8-HQ)]Cl, where, M = Ni(ii), Cu(ii) and Zn(ii),8-HQ= 8-Hydroxyquinoline. Chemical forms are obtained from their 1 H, 13CNMR, Mass spectra (for (L)), FT-IR and U.V spectrum, melting point, molar conduct.Using flame (AA), % M is determined in the complexes.The content of C, H, N and S in the (L) and its complexes was specified. Magnetic susceptibility and thermal analysis (TGA) of prepared compounds were measured.The propose geometry for all complexes[M2 (L)Cl4 ] wa
... Show MoreFeature selection (FS) constitutes a series of processes used to decide which relevant features/attributes to include and which irrelevant features to exclude for predictive modeling. It is a crucial task that aids machine learning classifiers in reducing error rates, computation time, overfitting, and improving classification accuracy. It has demonstrated its efficacy in myriads of domains, ranging from its use for text classification (TC), text mining, and image recognition. While there are many traditional FS methods, recent research efforts have been devoted to applying metaheuristic algorithms as FS techniques for the TC task. However, there are few literature reviews concerning TC. Therefore, a comprehensive overview was systematicall
... Show MoreThe present study focused mainly on the vibration analysis of composite laminated plates subjected to
thermal and mechanical loads or without any load (free vibration). Natural frequency and dynamic
response are analyzed by analytical, numerical and experimental analysis (by using impact hammer) for
different cases. The experimental investigation is to manufacture the laminates and to find mechanical
and thermal properties of glass-polyester such as longitudinal, transverse young modulus, shear modulus,
longitudinal and transverse thermal expansion and thermal conductivity. The vibration test carried to
find the three natural frequencies of plate. The design parameters of the laminates such as aspect ratio,
thickness
The main objective of this research is to design and select a composite plate to be used in fabricating wing skins of light unman air vehicle (UAV). The mechanical properties, weight and cost are the basis criteria of this selection. The fiber volume fraction, fillers and type of fiber with three levels for each were considered to optimize the composite plate selection. Finite element method was used to investigate the stress distribution on the wing at cruise flight condition in addition to estimate the maximum stress. An experiments plan has been designed to get the data on the basis of Taguchi technique. The most effective parameters at the process to be find out by employing L9
... Show MoreA field experiment was conducted in the growth season 2019-2020 at the botanical garden of the Biology Department at the College of Education for Pure Sciences/Ibn Al-Haitham, University of Baghdad-Iraq. The experiments’ purpose is to determine the effects of different melatonin concentrations on some morphological and physiological characteristics of mung (Vigna radiata L.) plant under the influence of three periods of drought (5, 10, 15 days). The results were showed that the increasing of water stress periods had significant effects in the reducing rates of the studied characteristics, especially at the period 15 days. The external treatment of different concentrations of melatonin reduced the drought effects and that’s led to signif
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