We studied the effect of Ca- doping on the properties of Bi-based superconductors by
adding differ ent amounts of CaO
to the Bi
2
Sr2La2-xCaxCu3O10+δ
compound. consequently, we
obtained three samples A,B and C with x=0.0, 0.4 and 0.8 respectively. The usual solid-state
reaction method has been applied under optimum conditions. The x-ray diffraction analy sis
showed that the samples A and B have tetragonal structures conversely the sample C has an
orthorhombic structure. In addition XRD analysis show that decreasing the c-axis lattice
constant and thus decreasing the ratio c/a for samples A,B and C resp ectively. The X-ray
florescence proved that the compositions of samples A,B and C with the ratio of
Bi:Sr :La(Ca):Cu which were about 2:2:2:3. Resistivity were measured at different
temperatures under zero magnetic f ields and the data were interp reted. Sample A shows that
semiconductor behavior, sa mple B showed a metal behavior andsa mple C showed a
sup erconductor behaviors with transition temperatureat zeroresistanceTc( off set)
were 85 K .
Rapid breakdown anodization (RBA) process was used to fabricate TiO2 sensor to measure pressure and humidity and sense gases at room temperature. This chemical process transformed Ti to its oxide (TiO2) as a powder with amorphous phase as X ray diffraction (XRD) technique confirmed. This oxide consisted from semi spherical nanoparticles and titania nanotubes (TNTs) as Scanning electron microscope (SEM) technique showed. TiO2 powder was deposited on Ti substrates by using electrophoretic deposition (EPD) method. Average pressure sensitivity was 0.34 MΩ/bar and hysteresis area was 1.4 MΩ .bar. Resistance of TiO2 decreased exponentially with the increasing of relative
... Show MoreA new derivative applied to the old gravity Bouguer map (served in 1940s and 1950s), taking regional study area covered the mid and south of Iraq. The gravity anomaly reflects a density contrast variation; therefore it is possible to use gravity inversion to the density and velocity model through layers (615m, 1100m, 1910m, 2750m and 5290m), the depth layers according to the power spectrum analysis of gravity Bouguer. The inversion is according to the integration of gravity anomalies of the each depth layer with the same depth of wells data, considered to the estimations and analysis of density and velocity scatters of the oil wells distribution with depth at the regional area. Taking the relation
... Show MoreDuration of each developmental stage of the house dust mite Dermatophagoides pteronyssinus together with the mortality percentage were observed at a combination of five different temperatures namely 20C°, 22.5C°, 25C°, 27.5C° and 30C° and four different humidities namely 55%, 75%, 85% and 95% r. h. Results showed that temperature had the greatest effect on the life cycle period. The higher the temperature the shorter the life cycle was aid versa verea. On the other hand, humidity seems to be less effectiveness, though at the higher temperature and humidity no development was occured. Mortality among all temperatures and humidities appeared nearly the same, but at higher temperature and higher humidity and because of mould g
... Show MoreIn this work; copper oxide films (CuO) were fabricated by PLD. The films were analyzed by UV-VIS absorption spectra and their thickness by using profilometer. Pulsed Nd:YAG laser was used for prepared CuO thin films under O2 gas environment with varying both pulse energy and annealing temperature. The optical properties of as-grown film such as optical transmittance spectrum, refractive index and energy gap has been measured experimentally and the effects of laser pulse energy and annealing temperature on it were studied. An inverse relationship between energy gap and both annealing temperature and pulse energy was observed.
The development of information systems in recent years has contributed to various methods of gathering information to evaluate IS performance. The most common approach used to collect information is called the survey system. This method, however, suffers one major drawback. The decision makers consume considerable time to transform data from survey sheets to analytical programs. As such, this paper proposes a method called ‘survey algorithm based on R programming language’ or SABR, for data transformation from the survey sheets inside R environments by treating the arrangement of data as a relational format. R and Relational data format provide excellent opportunity to manage and analyse the accumulated data. Moreover, a survey syste
... Show MoreIn many oil-recovery systems, relative permeabilities (kr) are essential flow factors that affect fluid dispersion and output from petroleum resources. Traditionally, taking rock samples from the reservoir and performing suitable laboratory studies is required to get these crucial reservoir properties. Despite the fact that kr is a function of fluid saturation, it is now well established that pore shape and distribution, absolute permeability, wettability, interfacial tension (IFT), and saturation history all influence kr values. These rock/fluid characteristics vary greatly from one reservoir region to the next, and it would be impossible to make kr measurements in all of them. The unsteady-state approach was used to calculate the relat
... Show MoreThe current study includes preparing a geometric proposal of the main parameters that must be worked within a seismic reflection survey to prepare a three-dimensional subsurface image. This image represents the Siba oil field located in Basra, southern Iraq. The results were based on two options for selecting these approved elements to create a three-dimensional image of the Mishrif, Zubair and Yamama formations as well as the Jurassic and Permian Khuff and the pre-Khuff reservoir area. The first option is represented in the geometry in option -1 is 12 lines, 6 shots, and 216 chs. The receiver density is 66.67 receivers / km2, so the shot density is the same. Total shots are 21000, which is the same number of receiv
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