A computerized investigation has been carried out on the design of six electrodes electrostatic lenses used in electron gun application. The Finite-Element Method (FEM) was used in the solution of Laplace equation for determine the axial potential distribution. The electron trajectory under zero magnification condition. The optical properties, spherical and chromatic aberrations, the object and image focal length and object and image position are calculated. A very good futures for the electron gun with these lenses have been computed where are a beam current of 8.7*10-7A can be supplied using cathode tip of radius 10nm.
Inelastic longitudinal electron scattering form factors for second
excited state C42 in 42Ti nucleus have been calculated using shell
model theory. Fp shell model space with configuration (1f7/2 2p3/2
1f5/2 2p1/2) has been adopted in order to distribute the valence
particles (protons and neutrons) outside an inert core 40Ca. Modern
model space effective interactions like FPD6 and GXPF1 have been
used to generate model space vectors and harmonic oscillator wave
function as a single particle wave function. Discarder space (core
orbits + higher orbits) has been included in (core polarization effect)
as a first order correction in microscopic theory to measure the
interested multipole form factors via the model
The ground state proton, neutron and matter densities and
corresponding root mean square radii of unstable proton-rich 17Ne
and 27P exotic nuclei are studied via the framework of the twofrequency
shell model. The single particle harmonic oscillator wave
functions are used in this model with two different oscillator size
parameters core b and halo , b the former for the core (inner) orbits
whereas the latter for the halo (outer) orbits. Shell model calculations
for core nucleons and for outer (halo) nucleons in exotic nuclei are
performed individually via the computer code OXBASH. Halo
structure of 17Ne and 27P nuclei is confirmed. It is found that the
structure of 17Ne and 27P nuclei have 2
5 / 2 (1d ) an
The charge density distributions (CDD) and the elastic electron
scattering form factors F(q) of the ground state for some even mass
nuclei in the 2s 1d shell ( Ne Mg Si 20 24 28 , , and S 32 ) nuclei have
been calculated based on the use of occupation numbers of the states
and the single particle wave functions of the harmonic oscillator
potential with size parameters chosen to reproduce the observed root
mean square charge radii for all considered nuclei. It is found that
introducing additional parameters, namely 1 , and , 2 which
reflect the difference of the occupation numbers of the states from
the prediction of the simple shell model leads to a remarkable
agreement between the calculated an
Plasma generated by a 1064 nm pulsed Nd: YAG laser with pulse duration of 10 ns concentrated onto an Al solid target under vacuum pressure was examined spectroscopically. The temperature and electron density specifying the plasma were measured by time-resolved spectroscopy of neutral atom and ion line emissions in the time period range of 300–2000 ns. An echelle spectrograph is utilized to appear the plasma emission lines. The temperature was obtained using the spectral line comparison method and the electron density was calculated using the Stark Broadening (SB) method. The electron density was characterized as a function of laser pulse energy. The time range where the plasma is optically thin and is also in local thermodynamic equilibri
... Show MoreThe ground state proton, neutron and matter densities andcorresponding root mean square radii of unstable proton-rich 17Neand 27P exotic nuclei are studied via the framework of the twofrequencyshell model. The single particle harmonic oscillator wavefunctions are used in this model with two different oscillator sizeparameters core b and halo , b the former for the core (inner) orbitswhereas the latter for the halo (outer) orbits. Shell model calculationsfor core nucleons and for outer (halo) nucleons in exotic nuclei areperformed individually via the computer code OXBASH. Halostructure of 17Ne and 27P nuclei is confirmed. It is found that thestructure of 17Ne and 27P nuclei have 25 / 2 (1d ) and 1/ 2 2s -dominantconfigurations, resp
... Show MoreThe first successful implementation of Artificial Neural Networks (ANNs) was published a little over a decade ago. It is time to review the progress that has been made in this research area. This paper provides taxonomy for classifying Field Programmable Gate Arrays (FPGAs) implementation of ANNs. Different implementation techniques and design issues are discussed, such as obtaining a suitable activation function and numerical truncation technique trade-off, the improvement of the learning algorithm to reduce the cost of neuron and in result the total cost and the total speed of the complete ANN. Finally, the implementation of a complete very fast circuit for the pattern of English Digit Numbers NN has four layers of 70 nodes (neurons) o
... Show MoreThe first successful implementation of Artificial Neural Networks (ANNs) was published a little over a decade ago. It is time to review the progress that has been made in this research area. This paper provides taxonomy for classifying Field Programmable Gate Arrays (FPGAs) implementation of ANNs. Different implementation techniques and design issues are discussed, such as obtaining a suitable activation function and numerical truncation technique trade-off, the improvement of the learning algorithm to reduce the cost of neuron and in result the total cost and the total speed of the complete ANN. Finally, the implementation of a complete very fast circuit for the pattern of English Digit Numbers NN has four layers of 70 nodes (neurons) o
... Show MoreThe complexity and partially defined nature of jet grouting make it hard to predict the performance of grouted piles. So the trials of cement injection at a location with similar soil properties as the erecting site are necessary to assess the performance of the grouted piles. Nevertheless, instead of executing trial-injected piles at the pilot site, which wastes money, time, and effort, the laboratory cement injection devices are essential alternatives for evaluating soil injection ability. This study assesses the performance of a low-pressure laboratory grouting device by improving loose sandy soil injected using binders formed of Silica Fume (SF) as a chemical admixture (10% of Ordinary Portland Cement OPC mass) to di
... Show MoreThe effect of electrolysis operating parameters on the removal efficiency of cadmium from a simulated wastewater was studied by adopting response surface methodology combined with Box–Behnken Design. As a new electrode design, spiral-wound woven wire mesh rotating cylinder electrode was used for cadmium removal. Current (240–400 mA), rotation speed (200–1000 rpm), initial cadmium concentration (200–600ppm), and cathode mesh number (30–60) were chosen as independent variables while the removal efficiency of cadmium was considered as a response function. The results revealed that the rotation speed has the major effect on the removal efficiency of cadmium. Regression analysis showed good fit of the experimental data to the second-or
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