This paper provides the result of an investigation to use of crushed clay brick as
aggregates in producing concrete. Eight different crushed clay brick aggregate concretes were
used in this investigation. Compressive strength, splitting tensile strength and pulse velocity of
crushed clay brick aggregates concrete were determined and compare to natural aggregate
concrete. The compressive strength of crushed clay brick aggregates concretes were always
lower than the compressive strength of natural aggregates concrete regardless the age of
concrete, but the crushed clay brick aggregates concrete showed better performance as the age of
concrete increases and average reduction in compressive strength were 33.5% at the age of 7
days but it becomes only 20% at the age of 56 days compared to natural aggregates concrete. The
splitting tensile strength of crushed clay brick aggregates concrete were always lower than
natural aggregate concrete, the reduction in splitting tensile strength of crushed clay brick
aggregates concrete is ranging between 11 and 26% with an average reduction of about 18.5%
compared to natural aggregates concrete. The pulse velocity of crushed clay brick aggregates
concrete were also lower than natural aggregates concrete, the reduction in pulse velocity of
crashed clay brick aggregates concrete is ranging between 6 and 22% with an average reduction
of about 14% compared to natural aggregates concrete.
The D.C. electrical properties of poly (ethylene oxide)/MgCl2 composites were investigated as a function of different MgCl2 filler concentrations (0, 5, 10, 15 and 20 wt.%) and different temperatures in the range (276–333)o K at three different polarizing fields. Resistivity:ï² and dc Conductivity: σ dc were measured, and the activation energy: Ea of the thermal rate-process of the electrical conduction was investigated. It was found that the current-voltage measurement results exhibited Ohmic resistance behavior, the composites exhibit negative temperature reliance of resistivity and enhancement in the D.C. electrical conductivity with both temperature and MgCl2 concentration. The determined activation energy was found to
... Show MoreLithium doped Nickel-Zinc ferrite material with chemical formula Ni0.9−2x Zn0.1LixFe2+xO4, where x is the ratio of lithium ions Li+ (x = 0, 0.01, 0.02, 0.03 and 0.04) prepared by using sol-gel auto combustion technique. X-ray diffraction results showed that the material have pure cubic spinal structure with space group Fd-3m. The experimental values of the lattice constant (aexp) were decreased from 8.39 to 8.35 nm with doped Li ions. It was found that the decreasing of the crystallite size with addition of lithium ions concentration. The radius of tetrahedral (rtet) and octahedral (roct) site were computed from cation distribution. SEM images have been taken to show the morphology of compound. The dielectric parameters [dissipation fa
... Show MoreThe objective of this paper is, firstly, we study a new concept noted by algebra and discuss the properties of this concept. Secondly, we introduce a new concept related to the algebra such as smallest algebra. Thirdly, we introduce the notion of the restriction of algebra on a nonempty subset of and investigate some of its basic properties. Furthermore, we present the relationships between field, monotone class, field and algebra. Finally, we introduce the concept of measure relative to the algebra and prove that every measure relative to the is complete.
Linear and nonlinear optical properties of epoxy/ Al2O3 nanocomposites system were studied for epoxy neat and (0.5, 1.5, 3, and 5) % Al2O3 nanocomposites.The band gap of epoxy and its nanocomposites was obtained at these weight ratios. Nonlinear optical properties experiments were performed using Q-switched Nd:YAG laser z-scan system.These experiments were carried out for different parameters: wavelengths (1064 nm and 532 nm), laser intensities (0.530, 0.679, and 0.772) GW/cm2 and weight ratio of Al2O3 nanocomposites. The results showed that the band gaps were decreased with increasing the weight ratio of nanoalumina except at 5wt% and the nonlinear refractive index coefficient is directly proportional to the incident intensities while o
... Show MoreThis study, establishes two stochastic monotonicity results concerning the run length of an upper one –sided Exponentially Weighted Moving Average (EWMA) control charts, based on the logarithm of the sample variance, for monitoring a process standard deviation, these properties cast interesting light on the control chart performance, and their extension to other one –sided EWMA control charts.
the structrual and mechanical properties of thin Ni films of different thicknesses deposited on coring glass substrate using lonbeam sputtering(IBS) technique under vacuum torr have been studied the TEM and electron
Nanoferrite materials have been synthesized by sol-gel auto combustion method. The effect of doping different percentages of Y2O3 (0.34 µm) on the physical and mechanical properties of selected mixed ferrite [(Li2.5Fe0.5) 0.9(Co4Fe2O4) 0.1] by adding 10% Cobalt ferrite was studied. Physical properties (i.e. .density, porosity and water absorption) were affected by the doping, where the density increased about 32% at 6 wt% Y2O3, while porosity has a drastically decreased about 80% at 6% Y2O3 and has a correlation effect on the mechanical properties(Splitting tensile strength and Vicker
... Show MoreThe present paper deals with prepared of ternary Se80-xTe20Gex system alloys and thin films. The XRD analysis improved that the amorphous structure of alloys and thin films for ternary Se80-xTe20Gex (at x=10and 20at.%Ge) which prepared by thermal evaporation techniques with thickness 250 nm. The optical energy gap measurements show that the optical energy gap decreases with increasing of (Ge) content from (1.7 to 1.47 eV)
It is found that the optical constants, such as refractive
index ,extinction coefficient, real and imaginary dielectric
constant are non systematic with increasing of Ge contents
and annealing temperatures