An optimization calculation is made to find the optimum properties of combined quadrupole lens which consists of electrostatic and magnetic lens. Both chromatic and spherical aberration coefficients are reduced to minimum values and the achromatic aberration is found for many cases. These calculations are achieved with the aid of transfer matrices method and using rectangular model of field distribution, where the path of charged-particles beam traversing the field has been determined by solving the trajectory equation of motion and then the optical properties for lens have been computed with the aid of the beam trajectory along the lens axis. The computations have been concentrated on determining the chromatic and spherical aberration coefficients in both convergence and divergence planes and the effects of changing both of excitation and effective length of lens are studied.
In this study miconazole nitrate was formulated as topically applied emulgel; different formulas were prepared using sodium carboxymethylcellulose (SCMC) and carboxypolymethylene (carbomer 941) as gelling agents. The influence of type of gelling agent and concentration of both oil phase and emulsifying agent on drug release was studied and compared with commercially available miconazole nitrate cream (Mecozalen®). The results of in vitro release showed that SCMC emulgel bases gave better release than carbomer 941 bases and the release of drug increase from both bases as a function of increasing the concentration of emulisifying agent. The oil phase had retardation effect when
... Show MoreThis paper discussed the solution of an equivalent circuit of solar cell, where a single diode model is presented. The nonlinear equation of this model has suggested and analyzed an iterative algorithm, which work well for this equation with a suitable initial value for the iterative. The convergence of the proposed method is discussed. It is established that the algorithm has convergence of order six. The proposed algorithm is achieved with a various values of load resistance. Equation by means of equivalent circuit of a solar cell so all the determinations is achieved using Matlab in ambient temperature. The obtained results of this new method are given and the absolute errors is demonstrated.
Recently, many materials have shown that they can be used as alternatives to chemicals materials in order to be used to improve the properties of drilling fluids. Some of these materials are banana peels and corn cobs which both are considered environmentally- friendly materials. The results of the X-ray diffraction examination have proved that the main components of these materials are cellulose and hemicellulose, which contribute greatly to the increasing of the effectiveness of these two materials. Due to their distinct composition, these two materials have improved the rheological properties (plastic viscosity and yield point) and reduced the filtration of the drilling fluids to a large extent. The addition rates used for each o
... Show MoreOil well drilling fluid rheology, lubricity, swelling, and fluid loss control are all critical factors to take into account before beginning the hole's construction. Drilling fluids can be made smoother, more cost-effective, and more efficient by investigating and evaluating the effects of various nanoparticles including aluminum oxide (Al2O3) and iron oxide (Fe2O3) on their performance. A drilling fluid's performance can be assessed by comparing its baseline characteristics to those of nanoparticle (NPs) enhanced fluids. It was found that the drilling mud contained NPs in concentrations of 0,0.25, 0. 5, 0.75 and 1 g. According to the results, when drilling fluid was used without NPs, the coeff
... Show MoreAn experimental study is made here to investigate the discharge coefficient for contracted rectangular Sharp crested weirs. Three Models are used, each with different weir width to flume width ratios (0.333, 0.5, and 0.666). The experimental work is conducted in a standard flume with high-precision head and flow measuring devices. Results are used to find a dimensionless equation for the discharge coefficient variation with geometrical, flow, and fluid properties. These are the ratio of the total head to the weir height, the ratio of the contracted weir width to the flume width, the ratio of the total head to the contracted width, and Reynolds and Weber numbers. Results show that the relationship between the discharge co
... Show MoreSource of energy and protein Field crops considered an important needed for human
beings Due of this fact increases should appear in the quantities of their production in order to
meet the needs of continuous increasing in the population of the glope year after year ;
otherwise, an increase in the gap between the amount of production and consumption will
occur .
This study aims to reveal the geographical distribution of the potato crop in the district
of Abu – Ghraib. For this purpose, a study conducted about the cultivated areas, production
and crop yields per Dunam for period of 7 years lasted from 2005-2011.
The study shows that potato is one of the most important field crops that are grown in
the Abu –
The aerodynamic and elastic forces may cause an oscillation of the structure such as the high frequency of the airfoil surfaces and the dynamic instability occurring in an aircraft in flight and failure may occur at a speed called flutter speed. In this work, analytical and numerical investigations of flutter limits of thin plates have been carried out. The flutter speed of rectangular plates were obtained and compared with some published results. Different design parameters were investigated such as aspect ratio, thickness and their effects on flutter velocity. It was found that the structural mode shape plays an important role in the determination of the flutter speed and the coupling between the bending and torsional mode is the main
... Show MoreChlorine doped SnS have been prepared utilizing chemical spray pyrolysis. The effects of chlorine concentration on the optical constants were studied. It was seen that the transmittance decreased with doping, while reflectance, refractive index, extinction coefficient, real and imaginary parts of dielectric constant were increased as the doping percentage increased. The results show also that the skin depth decrease as the chlorine percentage increased which could be assure that it is transmittance related.
The effect of the concentration of the colloidal nanomaterial on their optical limiting behavior is reported in this paper. The colloids of sliver nanoparticles in deionized water were chemically prepared for the two concentrations (31 ppm and 11ppm). Two cw lasers (473 nm Blue DPSS laser and 532 nm Nd:YAG laser) are used to compare the optical limiting performance for the samples. UV–visible spectrophotometer, transmission electron microscope (TEM) and Fourier Transformation Infrared Spectrometer (FTIR) were used to obtain the characteristics of the sample. The nonlinear refractive index was calculated to be in the order of 10-9 cm2/W. The results demonstrate that the observed limiting response is significant for 532nm. In addition, t
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