In this study, a mathematical model is presented to study the chemisorption of two interacting atoms on solid surface in the presence of laser field. Our mathematical model is based on the occupation numbers formula that depends on the laser field which we derived according to Anderson model for single atom adsorbed on solid surface. Occupation numbers formula and chemisorption energy formula are derived for two interacting atoms (as a diatomic molecule) as they approach to the surface taking into account the correlation effects on each atom and between atoms. This model is characterized by obvious dependence of all relations on the system variables and the laser field characteristics which gives precise description for the molecule – surface interaction dynamics as a function of the normal distance from the surface and the distance between atoms .Our mathematical model is applied to the Na2/W(100) system .It is found that the type of interaction between the atoms and surface , whether it is repulsive or attractive , is determined by the laser strength where the repulsion between the two atoms increases with the laser strength increasing. So it makes sure that the laser field can be consider as a tool to control the ionization and dissociation processes that happen on the solid surface.
thirty adult NewZealand rabbits used in this study, they were divided in to two groups (control and treaded with Helium — Neon laser). A square skin flap done on the medial aspect of the auricle of both sides, a square piece of cartilage incised, pealed out from each auricle and fixed in the site of the other, then the flaps sutured .The site of the operation in the rabbits of the treated group were irradiated using a Helium —Neon laser with (5mw) power for (10 days) began after the operation directly, (3 rabbits) from each group used for collection of specimens for histopathological examination at the weeks (1,2,3,4, & 6) weeks post the operation .The results revealed Early invasion of the matrix with elastic fibers which continue to t
... Show MoreIn this paper , the CO2 laser receiver system is designed and studied, with wavelength laser 10.6 ?m in room temperature , and to evaluate the performance and discussion it via the package of optical design (ZEMAX), from its output the Spot Diagram is measured through RMS ,and from the Ray fan plot , the aberrations is found which is the normal error for the best focus named (under corrected ) , the other output was the Geometric Encircled Energy in the spot diagram . and found that the radius of spot diagram at 80% (R80%) from the total energy ,and focal shift .The designed system have high efficiency and low cost .
This research investigates new glasses which are best suitable for design of optical systems
working in the infrared region between 1.01 to 2.3μm. This work is extended to Oliva & Gennari
(1995,1998) research in which they found that the best known achromatic pairs are (BAF2-IRG2; SRF2-
IRG3; BAF2-IRG7; CAF2-IRGN6; BAF2-SF56A and BAF2-SF6). Schott will most probably stop the
production of these very little used and commercially uninteresting IRG glasses. In this work equally
good performances can be obtained by coupling BAF2, SRF2&CAF2 with standard glasses from Schott
or Ohara Company. The best new achromatic pairs found are (SRF2-S-TIH10; CAF2-S-LAL9; CAF2-SLAL13
and CAF2-S-BAH27). These new achromatic pai
The aim of this research is to design and construct a
semiconductor laser range finder operating in the near infrared range
for ranging and designation. The main part of the range finder is the
transmitter which is a semiconductor laser type GaAs of wavelength
0.904 μm with a beam expander and the receiver; a silicon pin
detector biased to approve the fast response time with it's collecting
optics. The transmitters pulse width was 200ns at a threshold current
of 10 Ampere and maximum operating current of 38 Ampere. The
repetition rate was set at 660Hz and the maximum operating output
power was around 1 watt. The divergence of the beam was 0.268o
the efficiency of the laser was 0.03% at a duty cycle of 1.32x
Abstract
The current research aims to examine the effectiveness of a training program for children with autism and their mothers based on the Picture Exchange Communication System to confront some basic disorders in a sample of children with autism. The study sample was (16) children with autism and their mothers in the different centers in Taif city and Tabuk city. The researcher used the quasi-experimental approach, in which two groups were employed: an experimental group and a control group. Children aged ranged from (6-9) years old. In addition, it was used the following tools: a list of estimation of basic disorders for a child with autism between (6-9) years, and a training program for children with autism
... Show MoreDespite all the possibilities held by Iraq for the production of poultry , but there is low and clear in the level of production and a rise in costs and a decline in per capita consumption is due to a number of reasons, including poor investment , stop government subsides , dumping policies , market Bolmottagat imported , the contribution of the merchant squandering of national capacity , weak base material for the growth of this sector , the security situation and the crisis of energy and others .
Despite all this research has shown that there are great investment opportunities in this very sector of the market size and absorptive capacity of his and the growth of per capita income and level of cul
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The avoidance strategy of prey to predation and the predation strategy for predators are important topics in evolutionary biology. Both prey and predators adjust their behaviors in order to obtain the maximal benefits and to raise their biomass for each. Therefore, this paper is aimed at studying the impact of prey’s fear and group defense against predation on the dynamics of the food-web model. Consequently, in this paper, a mathematical model that describes a tritrophic Leslie-Gower food-web system is formulated. Sokol-Howell type of function response is adapted to describe the predation process due to the prey’s group defensive capability. The effects of fear due to the predation process are considered in the first two levels
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