Physics

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Electrochemical properties of Sol-gel WO3 films Co-doped with Ti and Zn
(216) Madleen Ahmad Mohammad Albalshi; Dr. Iyad Saadeddin; Dr. Mohammed Suleiman
WO3 nanoparticles doped with Ti (W1-xTixO3) and co-doped with Ti and Zn (W1-xTix-YZnyO3) have been prepared on FTO/glass substrate, using wet chemical method (dipping in a sol-gel). The Ti molar concentration into W1-xTixO3 ranges 0-30 % in steps of 5%. Best electrochromic properties were observed for composition that has Ti nominal concentration of 5% (W0.95Ti0.05O3). This was evidenced from cyclic voltammetry (CV), chronoamperometry (CA), and transparency during CA measurements. The composition that gives best electrochromic properties (W0.95Ti0.05O3) was chosen to prepare WO3 nanocrystallite films co-doped with Zn for the first time (W0.95Ti0.05-yZn yO3). The Zn molar concentration in these films varied 1-5%. From CV and CA measurements, Co- doped WO3 films showed better electrochromic performance than Ti single doped films. From co-doped films, the best electrochromic properties were observed for films that contains 3% of Zn (W0.95Ti0.02Zn0.03O3). The transparency spectrum of W0.95Ti0.02Zn0.03O3 electrode shows a high improvement in coloration efficiency compared to the coloration efficiency of W0.95Ti0.05O3 electrode. The stability of the prepared materials is also tested in H2SO4 electrolyte, though cycling electrodes for at least 6000 cycles.
Noise Pollution in Factories in Nablus City
(2001) Mahmoud Mohammad Abdel-Ali; Dr. Issam R. Abdel-Raziq; Dr. Zaid N. Qamhieh
Noise pollution is getting more and more important issue, especially in the industrialized and developed countries. Industrial noise is a serious environmental problem, which annoys us and disrupts our daily activities. In West Bank, however, there are so far no regulatory laws to limit high industrial noise level. Due to general unawareness about the ill effects of high noise levels, the owners of factories pay negligible attention to provide safety measures to their workers. Accordingly, this study is concerned in measuring the equivalent noise levels Le., in 38 factories in Nablus City, then comparing them with the international standards of noise. The obtained mean-value of these levels is 85.5 dB (A). It has been found that the Lcq values for 40% of the selected factories are higher than the adopted international standards. These factories are considered noisy sources to the workers. The continuous exposure of the workers to such high noise levels can cause hearing damage, speech masking and annoyance. High-level noise not only hinders communication between workers, but, depending upon the level, quality, and exposure duration of the noise, it may also result in different type of physical, physiological and psychological effects on the workers. This study suggests some recommendations and advice -for the workers in the factories, owners of the factories and for the Palestinian authorities to relieve the noise pollution problem in factories in Nablus City.
Indoor Radon Concentration Measurement in Homes in Old City of Nablus
(2001) Alan Mohammed Daraghmeh; Dr. G. Saffarini
The indoor radon concentrations in the old city of Nablus have been measured by using Solid State Nuclear Track Detectors (SSNTDs). After ninety days, the (SSNTDs) were collected and etched chemically by (6.25 N) NaOH solution for an hour at a temperature of (98 ± 2) C ° . The number of tracks per unit area in each detector was measured by using an optical microscope with 100 magnification power. lt was found that the radon concentrations vary between (81.31 Bq/m3) to (135.72 Bq! mi ). The values of the average radon concentration inside the kitchens, sleeping and setting rooms are (116.01 Bq m³), (101.78 Bq/ m³), and (79.92 Bq/m³), respectively. The total average radon concentration in homes in the old city of Nablus is found to be equal (98.8 Bq/m³) which corresponds to an average effective dose equivalent of (4.94mSv/y), which is higher than the globally accepted value of (1.3 mSv/y). Poor ventilation is believed to be the main reason for the elevated indoor radon concentrations in the homes of Nablus old city.
Indoor Radon Concentration Measurements in Four Hospitals and Two Health Centers in Nablus City
(2001) Nidal Khaled Mohamed Dwaikatt; Dr. Ghassan Saffarini
Indoor radon concentration has been measured in four hospitals (AL-—Watani, AL- Ethad,- Rafedia, AL -Enjeli) and two health centers (Mustwasf AL —Tadamon, Mustwasf AL-Rahma) in Nablus City. Forty-six solid state nuclear track detectors (SSNTDs) and fourteen kodalpha detectors were distributed in various locations among the four hospitals and the two health centers. Four SSNTDs and one-kodalpha detectors were lost. The SSNTDs detectors were etched in 6.25N NaOH at 98 ± 2 C° for about one hour and read under an optical microscope with magnification 100. The kodalpha detectors were read by the manufacturer in France. Indoor radon concentrations were calculated by using two calibration factors (5.3 ± 0.5) and (6.68 ± 0.02) and compared with the values obtained from the kodalpha detectors. The results that were calculated by our calibration factor (6.68 ± 0.2) present high correlation with those obtained from kodalpha detectors. The single values of radon concentrations of the calibration factor (6.68 ± 0.02) are more comparable, than those calculated by using the calibration factor (5.3± 0.5), with those obtained nom using the kodalpha detectors. According to the results obtained from the calibration factor (6.68 ± 0.02) radon concentration vary considerably from about 11 to 154 Bq m⁻³ in AL—Watani, 4 to 200 Bq m⁻³ in AL—Ethad, 6 to 287 Bq ni`3 in Rafedia, 12 to 35 Bq m⁻³ in AL —Enjeli, 14 to 96 Bq m⁻³ in AL—Tadamon, and 32 to 54 Bq rn'3 in AL-Rahma. The average radon concentration is found to be 61.21 Bq m⁻³; in AL -—Watani, 33.28 Bq m⁻³ in AL~Etl1ad, 92.03 Bq m⁻³ in Rafedia 23.85 Bq m⁻³ in AL -Enjeli, 55.19 m⁻³ in AL -Tadamon and 45.84 Bq m⁻³ in AL-Rahma. On the basis of these values, the average of lifetime risk of radon induced lung cancer are, respectively, 6.19 x 10⁴, 3.26 x 10⁴, 9.29 x 10⁴, 2.41 x 10⁴ , 5.57 x 10⁴ and 4.63 x 10⁴ in AL-Watani, AL—Ethad, Rafedia, AL—Enjeli, AL—Tadamon and AL—Ral1ma. In terms of dose equivalent these average radon concentrations correspond to the effective dose equivalent of 3.6, 1.66, 4.60, 1.19, 2.76 hand 2.29 mSv/y, respectively. Except in AL—Enjeli tl1ese doses are higher than the global value of 1.3 mSv/y. Radon concentration results indicate that in some rooms the values exceed the 150 Bq m⁻³ which need remedial action.
The Magnetic Properties of The Alloys Fe(Al, Mn) System
(2001) Sabri Ahmed Al-Tannah; Dr. M. Y. Seh
In this thesis we study the magnetic properties of the alloy system Fe(Al1-xMnᵪ), for x=0.31 , 0.35 , 0.60 and 0.80,by measuring the susceptibility in the temperature range 300 <= T <= 650 K° in very small ac magnetic field. The analysis of the susceptibility curves show that the sample with x=0.31 is paramagnetic, while the samples with x=0.35, 0.60 and 0.80 are ferromagnetically ordered. The susceptibility for x=0.31 obeys the Curie-Weiss law with a negative paramagnetic temperature (ɵp= -144K) and shows nearly a straight line with nearly the same susceptibility during all the process. For the other samples (with x=0.35, 0.60 and 0.80) show the coexistence of ferromagnetic and antiferromagnetic behavior with Neel temperature (Tn)= 335, 387 and 393 K and with paramagnetic temperature ɵp=g 340,393 and 425 K respectively. It is clear that the sample with x=0.31 exhibits only one paramagnetic phase, but for the other samples, two phases exist; antiferromagnetic phase below Neel temperature and paramagnetic phase above Neel temperature. The Fe(Al1-xMnᵪ) alloy system is very sensitive to temperature and the measured values for both susceptibility and Neel temperature during heating do not coincide with those values during cooling.
An Educational Biogas Project in Tulkarem
(2003) Ayoub Mohamed Eshraideh; Dr. Muneer Abdoh; Dr. Abdellatif Mohamed
The construction and production of biomass digesters has become very important in recent years due to their wide advantages. A systematic study of different properties of the biogas and its amount provides us with a great deal of information about digesters. Thus the appropriate nature and type of digesters are suitable for different areas in Palestine. The experiment described in this work was carried out in Tulkami city in the northern part of Palestine. The floating drum type of digesters was used in this work. When the addition rate of slurry added on daily basis was 50 liters/day, the amount of biogas produced is 0.685 m³, the average pH is 7.91 and the average ambient air temperature is 34.055°C while for the 100 liters/day rate, the amount of biogas produced was 1.610 m m³ the average pH is 7.96, and the average ambient air temperature is 34.29°C. In both cases the slurry temperature was 27°C. Therefore, the possibility of making use of biogas as a source of energy in Palestine is promising and building more biogas digesters in Palestine is recommended.
The Melting Dynamics of Nanoscale Pd Clusters : A Molecular Dynamics Study Using The Modified Embedded Atom Method
(2003) Saja Ibrahim Abdul-Hadi; Dr. N. J. Jisrawi; Dr. M. Abu-Ja'far
Clusters are systems of atoms that contain something between tens and tens of thousands of atoms. They form a link between individual atoms and the bulk, their finite size and large proportion of surface area; give them a special position in solid state physics. In this work, molecular dynamics simulations employing the modified embedded atom potential are used to• study the melting properties of seven Palladium "Magic Number" clusters. The clusters’ behavior, change of structure, latent heat per atom, atomic positions, and melting temperatures of each cluster were calculated. The most important results obtained in this work are: The calculation of the dependence of the melting temperature on cluster size. It is found that clusters have melting temperatures so much lower than of bulk that increase with the size of the cluster. The latent heat of fusion has the same behavior. Melting does not occur at a specified temperature, but in a range of melting temperatures going from the outermost shells to the inner shells of the cluster. In addition to this hysterisis in the transition temperature with cooling, the stability ofthe icosahedral structure is also studied.
First Principle Electronic Structure Calculations of Ternary Alloys. BNxP1-x, GaxB1-x N and BxIn1-x N inZinc Blende Structure
(2008) Baseemeh Daas Fareed Zpeedeh; Dr. Musa El-Hasan; Dr. Rezek M. Estaiteh
In this work full-potential linearized augmented plane wave method (FP-LAPW) within the density functional theory (DFT) and within generalized gradient approximation (GGA) are used to investigate, electronic band structure, structural properties and thermodynamic properties of III (In, B, Ga) - V (N, P ) compounds and their ternary alloys of BNxP1-x, GaxB1-xN, BxIn1-xN in zinc blende structure. The present DFT-GGA calculations have shown direct band gap energy in zinc-blende phase for InN, GaN, and indirect band gap energy for BN and BP. Here, the conduction band minima of both InN and GaN are located at Γ point, while that of BN is at a position lying along Γ–X direction and BP at Γ–∆min . In our work we have found that the band gap engineering of BNxP1-x, GaxB1-xN, BxIn1-xN alloys have been studied for range of constituents (x= 0.25, 0.50, 0.75). The downward band gap bowing seems the largest in GaxB1-xN alloy comparable with the other alloys considered in this work. Even for a small amount of contents (x), adecrease of the electronic effective mass around Γ point appears for BNxP1-x, GaxB1-xN, BxIn1-xN alloys manifesting itself by an increase of the band curvature . The calculated cross over from indirect to direct band gap of ternary alloys has been found to be consistent with the experimental measurements. At last, the determinations of the band gaps of alloys as a function of contents, the concentration range of constituents leading to metallic character of the alloys, the change of the electronic effective mass around (Γ) as a function of the cross over from indirect to direct band gap of the alloys which are direct on one end, indirect on the other end are main achievements in this work. We have found also that the optimize volume and the thermo- dynamic properties were different with different concentrations of the component of their ternary alloys above and we have also analyzed the relative stability, the bulk modulus, and the minimized energy of these ternary compounds.
Ga1-xMnxN Magnetic Semiconductors: First-Principles Study
(2008) Farah Ali Deib Saleh; Dr. Abdel-Rahman Abu-Labdeh; Dr. Mohammed Abu-Jafar
We present the results of First-Principles calculations of the magnetic semiconductors for systems taking the concentrations (0.0,0.125, 0.25, 0.50, 0.75 , 1.00) in the Zinc-blende Structure (ZB-Structure), using a self-consistent full-potential linearized augmented plane-wave (FP-LAPW) method implemented by the WIEN2K package. The local spin density approximation (LSDA) as well as the generalized gradient approximation (GGA) are used to treat the exchange correlation potential, and taking into account spin polarization. In order to design new or employ the existing diluted magnetic semiconductor materials, the underlying mechanisms of magnetism must be understood. The total energy versus lattice constant is obtained using the spin density functional theory (DFT). It is found that the equilibrium lattice parameters strongly depend on the concentration of the Mn-dopant (x ). Also we found that the energy band gaps ( ) for these systems depend on (x ), in other words the energy band gap decreases by increasing the Mn concentration. We mainly studied the Bulk parameters of our system, band structures, and magnetic properties. We made numerical investigations of the structural, magnetic properties for simple cases under pressure, in other part of our results we report an analysis of structures, magnetic properties of the , i.e GaN doped with Mn, with different concentrations, 0.125, 0.25, 0.5, 0.75 and so for major, minor compounds (GaN, MnN).
XO(X=Be, Zn) Compounds Under High Pressure
(2008) Omar Mahmood A. Isleem; Dr. Mohammed S. Abu-Ja'far
The structural phase transformations of semiconductors under high pressure have recently attracted a lot of attention. Experimental studies in this field are very difficult  and expensive, the computational physics programs make these studies very easy, very accurate and inexpensive. The computational approach enables us to know the atomic structures of materials, the electronic properties and give the chance to modify the bonding between atoms to create novel materials with predetermined properties. In the present study  the Full-Potential Linearized Augmented Plane-Wave (FP-LAPW) (which is included in a computer code WIEN2K) method depending on the Density Functional Theory (DFT) were used  to investigate the structural phase transformations of BeO and ZnO compounds under high pressure. In these calculations, the local density approximation(LDA), the gradient generalized approximation (GGA) and the modified Wu- Cohen-GGA approximation for the exchange correlation potential have been used. For BeO the equations of state (EOS’s) of wurtzite(WZ), zinc-blende(ZB) and rock salt (RS) have been calculated. From these (EOS’s) the transition under high pressure is occurred from wurtzite  to rock salt and from zinc-blende to rock salt structures, the transition pressure and the structural properties have also been calculated. The energy band gap for all phases of BeO have been calculated and a large band gap was found to be  (6 ~ 8 eV) which is  indicating that BeO is a good insulator. The same work was done for ZnO using the same method and the same approximations. A number of transition phases is predicted for ZnO, wurtzite to rock salt, wurtzite to cesium chloride, zinc-blende to rock salt, zinc-blende to cesium-chloride and rock salt to cesium-chloride. The transition pressure for each case was calculated. The structural properties have also been calculated and finally the energy band gap for each phase was investigated. Small energy band gap (0.3 ~1.5eV) is found, which means that ZnO behaves as  a semiconductor. The most important results of this study are: 1-The present calculations agree very well with the available experimental data and the other theoretical calculations. 2- The transition from structure to another is possible under high pressure. 3-BeO behave as an insulator in all its structures. 4-Wurtzite found to be the ground state for BeO compound at zero temperature. ZnO behave as a semiconductor in all its structures except in cesium-chloride structure it behaves as a semi-metal
Effects of a Uniform Applied Magnetic Field and Temperature on the Magnetic Properties of the Dipolar Anti-ferromagnetic planar System: Parametric Study
(2008) Naim Mahmoud Malak; Dr. Abdel-Rahman Mustafa Abu-Labdeh
The effects of a uniform external magnetic field, with strength parameter of h, on the magnetic properties of a two-dimensional square dipolar antiferromagnetic planar system, with sizes (104 X 104,64 X 64,32 X 32), have been determined for both zero and finite temperatures. In this study, the classical spins are confined to the plane of the system and interact through a nearest neighbor antiferromagnetic exchange interaction, the long-range dipolar interaction, and a uniform external magnetic field along the axis of the lattice. Throughout, the strength of the exchange interaction is assumed to be antiferromagnetic and fixed at −1.2g, where g is the strength of the dipolar interaction. At zero temperature, the ground state calculations show that the system switches from ferromagnetic phase (FE phase) to the dipolar antiferromagnetic phase (AF phase) at ho = 6.00g as the applied field is decreased. As the applied field is decreased further, the spin configuration starts to turn antiferromagnetically perpendicular to the applied field in a continuous manner. As the applied field goes to zero, the system favors the dipolar antiferromagnetic in which the spins are aligned perpendicular to the field (AF1 phase). At finite temperature, the magnetic phase diagram for the system has been determined as a function of both h and T using Monte Carlo simulations. At low temperatures, the results from simulations show that the system exhibits a first order transition from the ferromagnetic phase to the dipolar phase (AF phase) as the field is decreased. When the applied field goes to zero, the system favors the dipolar phase in which the spins are ordered at   with the axis of the lattice (AF2 phase). At low fields, the Monte Carlo results indicate that the system exhibits a second order transition from the dipolar antiferromagnetic phase to the paramagnetic phase as the temperature is increased. However, at high fields and for low temperatures the system favors the ferromagnetic phase. As the temperature is increased the system gradually disorders. In addition, Monte Carlo simulation results show that there exists a range of the magnetic field values in which the system exhibits a first order reorientation transition from the dipolar antiferromagnetic phase to the ferromagnetic phase as the temperature is increased.
Electronic, Structural and Magnetic Properties of Al1-xMnxN in Zincblende Structure: First Principle Study
(2009) Raed Tawfiq Aref Jaradat; Dr. Mohammed Abu Jafar; Dr.Abed Arrahman Abu Libdeh
We apply a First-Principles method to calculate the electronic structure and magnetic properties of the semiconductors Al1-xMnxN alloys by taking the concentrations (0.0, 0.25, 0.50, 0.75 , 1.00) in the zincblende structure (ZB), using a self-consistent full-potential linearized augmented plane-wave (FP-LAPW) method within the local-spin-density functional approximation (LSDA) and the generalized gradient approximation (GGA). Local spin density approximation (LSDA) and the generalized gradient approximation (GGA) are used to treat the exchange correlation energy. We studied the evolution of the band structure and magnetic moment as a function of the lattice parameter of the MnN compounds and the ternary alloys Al1-xMnxN. The binary compound MnN and also the ternary alloys with(x=0.5 and 0.75) magnetization increases as the lattice parameter increase and tend to saturate at the value 4 B for MnN and 8 B for the ternary alloys, as the material lattice (MnN) expansion the material goes from paramagnetic to ferromagnetic phase. We also found that the ternary alloy with x=0.25 is ferromagnetic and candidate to be half-metallic material, the majority spin states are metallic and the minority spin stats are insulating, for the other concentrations(x=0.5 and 0.75) these are found to be ferromagnetic semimetals, the bands are crossing the Fermi energy for both spin up and spin down (majority spin and minority spin) (the Fermi level lies in the band). The total energy versus lattice constant is obtained using the spin density functional theory. It was found that the equilibrium lattice parameter and the total magnetic moment strongly depend on concentration of Manganese atoms.
Influences of a Uniform External Magnetic Ffiled on the Magnetic Properties of the Dipolar Heisenberg System
(2009) Thaer Abu Lebdeh; Dr. Abed Arrahman Abu Libdeh
The effects of a uniform external parallel magnetic field, with strength h, on the magnetic properties of the Heisenberg system on a square lattice of size 32 X 32 have been investigated using Monte Carlo (MC) method. The model consists of three dimensional classical spin vectors in which the spins interact through the dipolar interaction, the magnetic surface anisotropy, the antiferromagnetic exchange interaction and a uniform external magnetic field along x-axis of the square lattice. The relative exchange parameter J/g, where g is the strength parameter of the dipolar parameter and J is the strength parameter of the exchange interaction, is fixed at the value -10 (i.e., J/g= -10). From a series of MC simulations, the magnetic phase diagrams for this system have been determined as a function of both the relative magnetic surface anisotropy parameter κ/g, where κ is the strength parameter of the magnetic surface anisotropy, and temperature T/g for three selected values h/g (i.e., h/g = 10, 20 and 27). At low temperatures and for k/g -4 the phase diagrams show perpendicular antiferromagnetic phase; while for k/g -4 the equilibrium phase is planer antiferromagnetic phase. The MC results also show that the phase boundary separating the two ordered phases appears to be first order with very small latent heat. Moreover, the MC results indicate that the phase boundary separating the two ordered states from the paramagnetic phase is second order. While the sequence of phases observed for deferent values of h is similar, at very low temperature the results show that the line of the first order transitions between the two ordered phases shifts towards the negative values of κ/g, with decreasing in its slope as the external field is increased. In addition, the MC results show that, both the perpendicular and planer phases are shrink as the applied field is increased.
FP-LAPW Study of Phase Changesin An(A = Al,IN, and B) Under High Pressure
(2009) Haneen Yousef Saeed Shalash; Dr. Mohammad Abu-Jafar; Dr.Abdel-Rahman Abu-Labdeh
In the last few years no other class of material of semiconductors has attracted so much scientific and commercial attention like the group III-nitrides( AlN, BN, and InN). The increasing interest is due to its extraordinary physical properties, which can be used in many new electronic and optoelectronic devices. The AlN is stable to very high temperatures in inert atmospheres. Another stable material in inert and reducing atmospheres is BN. It is a very good electrical insulator. It offers very high thermal conductivity and good thermal shock resistance. In N has attracted considerable attention due to the repeated observation of an effective band gap in the range around 0.7 eV by optical techniques, this smaller band gap value would extend the possible emission range of optoelectronic devices based on III-nitrides from the deep-UV down to the near-IR region. Very prominent examples are the short wavelength Light emitting diodes (LED’s) and laser diodes, which take advantage of the wide band gap of AlN. InN also has been expected to be a suitable material for electronic devices such as high mobility transistors due to its small effective mass. The effect of pressure on the electronic properties of (AlN, BN, and InN) are  investigated using both experimental and theoretical methods. In this study, we carry out all-electron full potential linearized-augmented plane waves (FP-LAPW) (which is included in a computer code WIEN2K) approach within the density functional theory (DFT) in the local density approximation (LDA), and the generalized gradient approximation (GGA) for the exchange correlations functional, which used to calculate ground-state energies, the lattice parameters, the bulk modulus and its derivatives, transition pressure and the band structures. The equation of state of wurtzite (WZ), zincblende(ZB) and rocksalt(RS) structures for (AlN, BN, and InN) compounds have been calculated.  In this study, the most important results are: 1.The present calculations agree very well with available experimental data and other theoretical calculations. 2.AlN compound behaves as an insulator in (WZ, ZB, and RS) structures. 3.BN compound behaves as a semiconductor for RS and ZB in LDA calculation and an insulator for RS and ZB in GGA calculation. 4.InN compound behaves as a semimetal in (WZ, ZB, and RS) structures. 5.The energy band gap for (WZ, RS, and ZB ) structures of AlN are found to be (4.42, 4.032, 2.7) eV respectively,  using  LDA method, and (4.17, 4.34, 3.275) eV respectively, using GGA method. 6.The energy band gap for (ZB and RS) structures of BN are found to be (4.36, 2.193) eV respectively, using LDA method, and (4.43, 1.71) eV respectively, using GGA method. 7.The energy band gap for (WZ, RS, and ZB ) structures of InN are found to be ( -0.264, 0.0838, -0.3896) eV respectively, using  LDA method, and (-0.3643, -0.277, -0.5136) eV respectively, using GGA method. 8.For AlN the transition pressure from wurtzite to rocksalt was found to be (10) GPa and from zincblende to rocksalt was found to be (4.64) GPa using GGA method, while the transition pressure from wurtzite to rocksalt was found to be 9.3 GPa and from zincblende to rocksalt was found to be 3 GPa using LDA method. 9.For InN the transition pressure from wurtzite to rocksalt was found to be 16.6 GPa and from zincblende to rocksalt was found to be 18.5 GPa using GGA method. 10.The transition pressure for BN compound from zincblende to rocksalt was found to be 500 GPa using GGA method.
Confined Hydrogen Atom In Spherical Cavity In N - Dimensions
(2009) Muzayan Abed Al Hameed Ali Shaqour; Prof.Sami Al-Jaber
In this research the Schrödinger equation for a confined hydrogen atom in a spherical cavity in N dimensional spatial space has been solved for N ≥3. The eigen functions as well as the eigen values have been determined. We show that the Schrodinger equation here doesn’t differ from that of the free hydrogen atom in N dimensions; therefore they have similar wave functions namely: (see The Equation in The PDF File) while they differ in energy. A series solution of the Schrödinger equation is adopted here, and then, by applying the boundary conditions to the wave functions we found the energy eigen-values.The dependence of the ground state energy eigen-values of a confined hydrogen atom for l = 0 for certain values of N, on the radius of the cavity S, has been examined. We found that they depend on the radius of the cavity S, we show that for a given N, if S increases the ground state energies decreases until they approach a limiting value which approaches the energy eigen value of that N of the free hydrogen atom. While as S decreases, the ground state energy eigen values increases up until it approaches zero at a minimum value of S that is called the critical cage radius (Sc ) at which the total energy of the confined hydrogen atom equals zero. The critical values Sc are calculated for dimensions from (2-10), whose values are 0.722890, 1.835247, 3.296830, 5.088308, 7.200250, 9.617367, 12.35000, 15.36350, 18.68200 respectively, (all the values here are multiples of Bohr radius (α0)=0.529x10-10 meters It is shown here that Sc increases as N increases. It is also shown that for a given S, the energy eigen-values for l=0 depend on the dimensionality of space N, that is, as N increases, the ground state energy eigen-values increase. The dependence of bound states of a confined H-atom, for a given S, as a function of N is investigated, and it is found that it decreases as N increases, while if we choose a larger value of S, the number of the bound states increases for each value of N. We found it interesting to compare the energy eigen-values of a confined hydrogen atom in a spherical cavity of a certain radius, with those energies of the corresponding energy eigen-states of a free hydrogen atom in the same dimension N. We found that the effect of confinement becomes more profound for larger N. Finally, I considered the behavior of pressure on the cavity as the radius S is varied. It has been shown that the pressure exerted on the atom increases as S decreases up to a certain maximum value which occurs at a radius value called Sp max max, but then it decreases within a small range of S.
FP-LAPW Calculations Of The Electronic Properties And Structural Phase Transformations In CoO And CdO
(2009) Kamal Falah Naji Mustafa; Dr. Mohammed Abu Jafar
In this thesis the Full-Potential Linearized Augmented Plane-Wave (FP-LAPW) method depending on the Density Functional Theory (DFT) was used to find the atomic structures of materials, the electronic properties and to investigate the structural phase transformations of CdO and CoO compounds under high pressure, and to know the conductivity and the ground state for these compounds. In these calculations the gradient generalized approximation (GGA),the local density approximation(LDA), W-Cohen approximation have been used. For CdO, the equations of state (EOS’s) of rocksalt (RS), zincblende (ZB),cesium chloride (CsCl) and wurtzite (WZ) have been calculated. From these EOS’s the transition under high pressure is occurred from rocksalt (RS) to cesium chloride (CsCl), from wurtzite (WZ) to cesium chloride (CsCl), from wurtzite (WZ) to rocksalt (RS), from zincblende (ZB) to rocksalt (RS), from zincblende (ZB) to cesium chloride (CsCl), and from wurtzite (WZ) to zincblende (ZB). The energy band gaps for all structures of CdO have been calculated. It is ~ - 0.5 eV for RS structure, so this structure indicates to be a semimetal. The CsCl structure indicates to be a semimetal too, because its band gap is ~ - 1.1 eV. The energy band gap is ~ 0.1 eV for ZB structure, which means the CdO compound is a semimetal in this structure. And it is ~ 0.1 eV for WZ structure, so the CdO compound is a semimetal too.The structural properties have also been calculated for all structures. We found the rocksalt (RS) structure is the ground state for CdO compound. The same work done for CoO and the same method with the same approximations was used, the equations of state (EOS’s) of rocksalt (RS), zincblende (ZB), and cesium chloride (CsCl), have been calculated. From these EOS’s, the transition under high pressure is occurred from rocksalt (RS) to cesium chloride(CsCl, from zincblende (ZB) to rocksalt (RS), and from zincblende (ZB) to cesium chloride (CsCl). The energy band gaps for all structures of CoO have been calculated. It is(- 0.5- 0.17 eV) for ZB, so this structure indicates a semimetal. It is between (0.771.1 eV) For CsCl, which means the CoO compound is a semimetal in this structure. Finally the energy band gaps is between (0.15 0.42 eV) for RS structure by using LDA and W-Cohen methods, so the structure is semimetal, but it is ~ 0.01 eV by using GGA method, so this structure is a semimetal too. The structural properties have also been calculated for all structures. We found the zincblende (ZB) structure is the ground state for CoO compound.
Electronic and Structural Properties of SCSb and Sc Punder High Pressure
(2009) Hani Ghaleb Yousif Najji; Dr.Mohammed Abu Jafar; Dr.Abed Arrahman Abu Libdeh
In the present study, the Full-Potential Linearized Augmented Plane Wave method that depends on the Density Functional Theory was used to investigate the structural phase transformations of ScSb and ScP compounds under high pressure. In these calculations, the local density approximation (LDA) and the gradient generalized approximation (GGA) for the exchange correlation potential have been used . For ScSb the equations of state (EOS's) of rock- salt(RS), cesium chloride(CsCl), zincblende(ZB) and wurtzite(WZ) have been calculated, from these (EOS's), it is found that a transition under high pressure is occurred from rock salt structure to cesium chloride structure. The transition pressure and the structural properties have also been calculated, the energy band gap for all phases of ScSb have been calculated and (-0.873,-0.683, 1.434, 1.481) eV band gaps were found and indicating that ScSb is semimetals and semiconductors respectively. The same work was done for ScP using the same method. A number of transition phases are predicted for ScP ; rocksalt to cesium chloride and wrutzite to zincblende. The transition pressure for each case was calculated. The structural properties have also been calculated, Finally the energy band gap for each phase was investigated. (-0.787,-0.583, 1.578, 1.6249)eV energy band gaps are found, which means that ScP behaves as metal, semimetal and semiconductor respectively. The most important results of this study are: 1.the structural parameters agree very well with the available experimental data and the other theoretical calculations. 2.the transition from structure to another is possible under high pressure, for ScSb the transition pressure from rocksalt to cesium chloride was found to be (31.5)GPa by LDA method and 35.4 GPa by GGA method. 3.For ScP the transition pressure from rocksalt to cesium chloride was found to be 69 GPa and from wurtzite to zincblende was found to be 84GPa by LDA method, while the transition pressure from rocksalt to cesium chloride was found to be 73.4 GPa and from wurtzite to zincblende was found to be 88 GPa by GGA method . 4.ScSb behaves as semimetal for rocksalt, metal for cesium chloride and semiconductor for zincblende and wurtzite phases using both LDA and GGA methods. 5.ScP behaves as semimetal for rocksalt, metal for cesium chloride and semiconductor for zincblende and wurtzite phases using both LDA and GGA methods. 6.Rocksalt was found to be the ground state for ScSb and ScP compound at ambient conditions.
Structural, Electronic and Magnetic Properties of Ga1-× Fe× N Alloys (X=0, 0.25, 0.5, 0.75, 1) in Zincblende Structure– First Principle Study)
(2009) Mahmoud Mohammad Ahmad Eissa; Mohammad Abu-Ja'far; Abder-Rahman Abu Lebedeh
A First-Principles method is used to calculate the electronic, structural, and magnetic properties of the semiconductors FexGa1-xN alloys by taking the concentrations x= 0 , 0.25 , 0.50 , 0.75, 1.0 in the zincblende structure (ZB), using a self-consistent full-potential linearized augmented plane-wave (FP-LAPW) method within the local-spin-density functional approximation (LSDA) and the generalized gradient approximation (GGA). The program used in our calculation is WIEN2K-code, which is written in Fortran 90 that works under Linux system. The evolution of the band structure was studied in addition to the magnetic moment as a function of the lattice parameter of the FeN compounds and the ternary alloys FexGa1-xN . It is found that the binary GaN has a (г-г) direct band gap energy ~ 1.9 eV, and a (г-x) indirect band gap energy ~3.2658eV using LSDA method, it is a semiconductor with no magnetic moment for the zincblende structure. It is found also that the band gap energy of the ternary alloys FexGa1-xN depend strongly on the concentration of Fe. The binary compound FeN is found to be non magnetic, while the total magnetic moment of the ternary alloys FexGa1-xN depend on the concentration of Fe. The lattice constant and the total magnetic moments of the ternary alloys FexGa1-xN calculated using GGA method and found to be larger than those obtained using LSDA, while the bulk modulus for the ternary alloys exGa1-xN obtained using GGA method are found to be smaller than those obtained usingLSDA.
The Effect of Noise Pollution on Arterial Blood Pressure and Pulse Rate of Workers in the Hospitals of Nablus City-Palestine
(2010) Rowaida Mahmoud Essa Sadeq; Prof.Isam Rashid; Dr. Zeid Qamhiyeh
This study analyzes the association of noise pollution level with systolic and diastolic blood pressure and heart pulse rate of workers in hospitals in the operating rooms (OR), neonatal intensive care units (NICU) and intensive care units (ICU). The sound pressure level (SPL) values in all studied hospitals are high compared with the recommended value which is 45.0 dB(A) in the daytime. The arterial blood pressure (Systolic and Diastolic) and heart pulse rate were measured for 95 workers (55 males and 40 females) which is the sample of workers in hospitals in Nablus city. The ages of workers are ranged from 20 to 73 yr. The duration of employment of those workers in the current job is ranged from 1 to 47 yr. In this study SBP, DBP and HPR are correlated positively (P- value 0.050) with the occupational noise levels in all studied hospitals. Whereas the Pearson coefficient correlation (R.) value of SBP, DBP and HPR in all selected hospitals are ranged from 0.546 to 0.906 of SBP, from 0.617 to 0.799 of DBP and from 0.658 to 0.869 of HPR. Moreover, this study showed that there are significant shifts in mean values of SBP, DBP and HPR before work and after 5 hours at least in all selected hospitals. Significant correlation was found between mean values of SBP, DBP and HPR with the duration of employment and age. Whereas the difference between means of SBP, DBP and HPR before and after work are 6.335 (mmHg) of SBP, 5.108 (mmHg) of DBP and 5.305 of HPR (beatmin).
Effect of Noise Pollution on Arterial Blood Pressure, Puls Rate and Heart Pulse Rate of School Children in Jenin City
(2010) Ruba Mohammed Anis Saeed; Dr.Zeid Qamhieh; Prof. Issam Rashid
This study reports the association of noise pollution level with blood pressure (systolic and dyastolic) and heart pulse rate in schools children. The test sample schools consist of six different schools chosen randomly in Jenin city. The measured sound pressure levels (SPL) in all tested schools were found to be above the standard international acceptable levels. Strong positive correlation (person correlation coefficient) was found between sound pressure levels in the sample schools from one side and blood pressures (R=0.96 for systolic and R= 0.98 dyastolic ) and heart pulse rate (R=0.991) from the other side. The average change rate of systolic and dyastolic blood pressures were found to be about 4.60 mm-Hg and 2.74 mm-Hg for every 76.86dB/hr change in SPL values, respectively. Also, the average rate of change of heart pulse rate was found to be about 5beats/min which reflects the strong correlation between changes of systolic blood pressure and heart pulse rate.

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