Full-text resources of PSJD and other databases are now available in the new Library of Science.
Visit https://bibliotekanauki.pl
Preferences help
Polish version English version Language
enabled [disable] Abstract
Number of results

Results found: 4

Number of results on page
first rewind previous Page / 1 next fast forward last

Search results

help Sort By:

help Limit search:
first rewind previous Page / 1 next fast forward last
1
Publication available in full text mode
Content available

Binding Energy of an Off-Center Hydrogenic Donor Impurity in a Finite Confining Potential Quantum Well

100%
Mikhail I., Ismail I.
Acta Physica Polonica A
|
2007
|
vol. 111
|
issue 3
373-385
EN
The binding energy of an off-center hydrogenic donor impurity in a finite confining potential quantum well was calculated by using a variational method of the Bastard type. New analytical expressions for the binding energy and for the initial deviation from the result of an infinite confining potential well were derived for the ground energy state. The sign of the initial deviation was found to depend on the location of the impurity. The analytical expressions were utilized further to derive some other important parameters.
2
Content available remote

Spin-Orbit Interaction in a Spherical Quantum Dot

81%
Mikhail I., Ismail I., El Shafee M.
Acta Physica Polonica A
|
2014
|
vol. 125
|
issue 5
1197-1205
EN
The conventional spin-orbit interaction due to the presence of an off-center impurity located in a spherical quantum dot of finite confining potential has been investigated. The different effective masses of dot and barrier are taken into consideration. The spin-orbit interaction has been calculated in the excited state (2p). The variational method has been applied by using a new form of the trial wave function in addition to the conventional form that has been used in previous work. The new form has the advantage of satisfying the boundary conditions at the interface between dot and barrier in the case of different masses. It has been shown that the spin-orbit interaction takes its highest value when the impurity is located in the vicinity of the position at which the radial electron probability takes its maximum value. The corresponding results of a central impurity has been investigated as the limiting case when the impurity radial coordinate tends to zero. The case of central impurity has been further explored by using the exact solution in the state (2p) of the radial Schrödinger equation in the presence of the impurity.
3
Content available remote

Characterization of TiAlV Films Prepared by Vacuum Arc Deposition: Effect of Substrate Temperature

81%
Abdallah B., Mrad O., Ismail I.
Acta Physica Polonica A
|
2013
|
vol. 123
|
issue 1
76-79
EN
Three TiAlV films have been prepared by vacuum arc discharge technique at different substrate temperatures (50, 300, and 400°C). The depositions were carried out from aluminum, vanadium and titanium elemental targets. The temperature effects on the crystalline quality and texture have been investigated by means of X-ray diffraction. Two phases have been identified and the grain size has been found to increase with temperature. The composition of the films has been determined by proton induced X-ray emission technique. The Ti ratio was found to increase with temperature. The microhardness, measured by the Vickers indentation method was found to decrease with temperature. X-ray photoelectron spectroscopy was used to study the chemical composition of the passive layer formed on the films by analyzing high resolution spectra of Al 2p, Ti 2p and V 2p. This layer was mainly composed of TiO_2 with a small participation of other oxidation and metallic states of Ti, Al and V.
4
Content available remote

Effect of alumina incorporation on restricting grain growth of nanocrystalline tin(IV) oxide

81%
Al-Angari Y., Kadi M., Ismail I., Gabal M.
Open Chemistry
|
2010
|
vol. 8
|
issue 2
331-340
EN
In this project, nanocrystalline SnO2 powders were successfully prepared by (a) citrate sol-gel and (b) direct precipitation methods. Powders were characterized using thermal analysis techniques (DTA-TG-DSC), X-ray powder Diffraction (XRD), surface area (BET) and electrical conductivity measurements. XRD patterns showed the presence of the cassiterite structure. SnO2 particles, prepared through sol-gel method exhibit crystallite sizes in the range from 3.1 to 22.3 nm when the gel is heat treated at different temperatures up to 900°C. SnO2 nanocrystallites prepared by the precipitation method are comparatively larger in size. The higher specific surface area was obtained for the powder prepared using sol-gel method and the obtained average grain size (d) is relatively large compared with that of the average crystallite size. The powders show a semiconducting behavior with increasing temperature. The higher conductivity obtained for SnO2 prepared by sol-gel method can be attributed to their smaller average crystallite size. XRD of alumina doped powder exhibits finer particles than pure SnO2. TEM images showed that the particles are spherical in shape and consist of a core of SnO2 surrounded by a coating of alumina. The calculated surface area was found to decrease with temperature increases. Due to the effective role of Al2O3 additive as a grain growth inhibitor for the matrix grains, the observed surface area for the coated materials are predominantly higher than for the uncoated materials. [...]
first rewind previous Page / 1 next fast forward last
JavaScript is turned off in your web browser. Turn it on to take full advantage of this site, then refresh the page.