This work studies the determination of stiffness factors , and in ferromagnetic crystal which enter into the calculations of anisotrophic constants of ferromagnetic crystal .
However , Value intervals of C3 which coresponds to the existence of
parallel states , and antiparallel states between the magnetic crystal vector and applied magnetic field vector . In addition , the suitable intervals for the magnetic jumps between two states have been found
Thick Films have been prepared by the chemical painting method from Tungsten Oxide nanopowdersas the source compound, which are prepared by milling in a high energy ball mill for variousspans of time (1-18h) on cleanedglasssubstratesunder limited the
rmal conditions. The temperature of the films have been changed from 25°C to 350°C. The films have been investigated for their sensing properties relating to 100 ppm ethanol vapor adsorption, using the (I–V) characteristics.The activation energy Ea for deposition films is deduced from the Arrhenius equation. The effect of the grain size and the thermal conditions on the sensing properties of the WO3thick films to ethanol vapor adsorption, as well as the correlations between The electrical conductivity of the WO3 thick films and the grain size of the material films are reported.The response time for films which have particle size about 70.54nm is defined at 300°C.
we seek to ensure laser stability , during its work , with time , and consistency of specifications and efficiency (returns), the cooling of the active medium and optical elements, are sensitive to the proper cooling method, in economic terms and in
terms ease of work.
Cooling technique helps prolonging the life of laser systems ,its stability and optimizing its operation. So the total cooling efficient lasers , Scientific and Industrial is essential when designing a laser and helps improving the specifications of lasers , gaseous or solid or semiconductor . In addition to that cooling has a good impact on the age of the laser , and safety of its use .
The designed cooling system , necessary for a certain laser system , depends on the amount of heat generated from the system(in Joule), which must be removed by the cooling system to keep the laser at specific temperature
The purpose of this research is to design and realization of an electronic apparatus which is able to control the process of irrigation that depending on soil moisture .This apparatus organize the process of irrigation, when the level of soil moistur
e under a specific value that it was chosen depending on water field capacity of crop ,it operates the pump which connected with it, and when the moisture level reaches that value the pump stops working.
The apparatus consists of two parts:
The first part: An electronic circuit using a number of operational amplifiers ,some electronic elements ,and voltmeter to measure voltage between load resistance which is in serial with resistance between two probes that set in soil.
The second part: An electrical part ,which provides a secure connection between the previous electronic circuit and water pump.
This study was carried out on a simple of black soil .The relation between electrical resistance of soil and volume of water used in irrigation was drawing for three values of distance between probes and power supply. We found an intense declination curves for small values of used water volume.
The potential health hazards of exposure to house dust come
either from particulate matters and adsorbed semivolatile
compounds, which become resuspended again. This research
aimed to study the loss on ignition (LOI)
of settled dust in two differ
ent houses in Homs city during a year,
The settled dust samples were collected by vacuum cleaner once a
week, Then the samples were sieved and the LOI values were
calculated.
The maximum and minimum values of LOI were obtained in
addition to monthly mean and median values.
Upon the results of this research some suggestions were made to
improve the public health.
Nylon-6/6 continuous Polymer nanofibers (NF) were produced by using conventional single needle
electrosprinng (ES) technique. In this paper several parameters, such as applied voltage and needle
diameter were investigated to optimize fiber morpholo
gy. The morphological and structure properties of
the fiber (average diameter, height, length, surface roughness and fiber shape) are visualized by Atomic
Force Microscopy (AFM). Good alignment of polymer nanofibres was confirmed by AFM and optical
microscopy observations. We concluded that fiber diameter increases with decreasing applied voltage
intensity and increasing the distance between the electrodes.
The MCNP5-beta code was used to calculate the reaction rate and the neutron energy response matrix of a neutron spectrometry consisting of a Polyethylene sphere with variable diameter and BF3 detector, using point and disk neutron sources, the reacti
on rate and the response matrix of disk neutron source shows higher values than those obtained for point neutron source in addition the response with disk neutron source at the energy range shows a maximum value for sphere of 10 inch diameter where the response with point neutron source stile increasing in this condition .The results obtained in this work for the disk neutron source agreed well with published results.
In this research the differential cross section for elastic scattering of electron neutrino (or anti neutrino) on the electron was calculated within and outside the frame work of the Standard Model (SM) of elementary particle physics. The mathematica
l relation of deviation from this model was also calculated. This study showed that there is a deviation from the standard model of the order for the electron neutrino flavor. The reference [16] was not able to appear it quite clearly and independently, but It showed the deviation on average for all flavors of neutrino together. Due to this deviation is very small, one can be neglected and therefore do not need to expand the framework of the standard model to include the electron neutrino mass, because in this case, it is located inside its framework.
Resonant photoemission of single crystals of the perovskite TbBaCoO3 has been carried out for freshly scraped surfaces. The resonance onset energy at the Co3p→3d threshold is used to explore the contribution of Co3d electrons to the electronic struct
ure of the valence band. The Energy Distribution Curves (EDC) corresponding to the valence band of the crystal were determined for radiation energies hv in the region of hv=60 eV. For 63.2 eV binding energy, the main contribution of Co 3d electrons was found in the main valence band peak located at 7.46 eV below the Fermi level, whereas the contribution of Tb4f electrons was found at energy 12.08 eV below the Fermi level. The results show that the density of states close to the Fermi energy is of Co3d/O2p character, with any Tb4f contribution.
We present a theoretical model for studying the oscillations among two-level quantum system when an interaction term is considered:
First, we present the two-level quantum system with a symmetric double square potential well in interaction, in one d
imension x, then we find the eigenvectors and the eigenvalues for this system by solving the stationary Schrödinger’s equation.
Second, we proved that a non perturbative approach can be conveniently used to write the Hamiltonian operator and to derive the Rabi’s equation for this system, directly applying the time evolution operator to the initial state of the system.
