-
Soliton Molecules in the Impurity Component of Self-Trapping Bosonic Impurity
Abdelaali Boudjemaa,
Mohammed-Elhadj Khelifa
Issue:
Volume 2, Issue 1, February 2017
Pages:
1-6
Received:
31 October 2016
Accepted:
26 December 2016
Published:
19 January 2017
DOI:
10.11648/j.wjap.20170201.11
Downloads:
Views:
Abstract: We investigate the dynamics of soliton molecules in the impurity component of a trapped Bose-Einstein condensate-impurity mixture (polaronic soliton molecules) using the time dependent Hartree-Fock-Bogoliubov equations in a quasi one-dimensional geometry. We show that the impurity component which obeys the self-focussing nonlinear Schrödinger equation, supports bright soliton molecules even for repulsive interspecies interactions. The binding energy, the width, the equilibrium state and the evolution of such solitons are deeply analyzed within variational and numerical means. We find that our variational and numerical calculations well coincide with each other.
Abstract: We investigate the dynamics of soliton molecules in the impurity component of a trapped Bose-Einstein condensate-impurity mixture (polaronic soliton molecules) using the time dependent Hartree-Fock-Bogoliubov equations in a quasi one-dimensional geometry. We show that the impurity component which obeys the self-focussing nonlinear Schrödinger equat...
Show More
-
Magnetic Investigations of Microcrystalline Na3Ln0.99-xEr0.01Crx (PO4)2 Orthophosphates Synthesized by Pechini Method (Ln=La, Gd)
S. M. Kaczmarek,
G. Leniec,
H. Fuks,
T. Skibiński,
A. Pelczarska,
P. Godlewska,
J. Hanuza,
I. Szczygieł
Issue:
Volume 2, Issue 1, February 2017
Pages:
7-18
Received:
17 October 2016
Accepted:
4 January 2017
Published:
23 January 2017
DOI:
10.11648/j.wjap.20170201.12
Downloads:
Views:
Abstract: Na3Ln (PO4)2 orthophosphates (Ln=La, Gd) doped with Er3+ and codoped with Cr3+ ion were synthesized by Pechini method and characterized by electron paramagnetic resonance (EPR) and magnetic susceptibility measurements. Low temperature EPR spectra were detected and analyzed in terms of temperature dependence and the structure of the obtained materials. They show that erbium and chromium ions substitute Ln3+ and also Na+ ions or Na+ channels forming complex EPR spectra. Both kinds of ions reveal ferromagnetic type of interaction which show some anomaly at the temperature between 10 and 15 K. Magnetic susceptibility reveals a weak antiferromagnetic kind of interaction dominating in the whole temperature range, from 3.5 to 300 K.
Abstract: Na3Ln (PO4)2 orthophosphates (Ln=La, Gd) doped with Er3+ and codoped with Cr3+ ion were synthesized by Pechini method and characterized by electron paramagnetic resonance (EPR) and magnetic susceptibility measurements. Low temperature EPR spectra were detected and analyzed in terms of temperature dependence and the structure of the obtained materia...
Show More
-
Modelling and Application of Vertical Refractivity Profile for Cross River State
Egbe Jesam Nna,
Ozuomba Simeon,
Enyenihi Henry Johnson
Issue:
Volume 2, Issue 1, February 2017
Pages:
19-26
Received:
31 October 2016
Accepted:
6 January 2017
Published:
28 January 2017
DOI:
10.11648/j.wjap.20170201.13
Downloads:
Views:
Abstract: In this paper six months data on primary radioclimatic parameters obtained using Radiosunde lunched by Nigerian Meteorological Agency (NIMET) in Cross River state, Nigeria is used to model the vertical radio refractivity profile. Cross River state is located at 4°57’North in latitude and 8°19'East. For each of the six months, cubic trendline equation is developed to predict the refractivity in the lower atmosphere (where height < 150 m above sea level). The cubic trendline equation can enable the determination of refractivity at any height less than 150m and also point refractivity gradient which requires the refractivity at 0 m and at 65 m above sea level. Sample point refractivity gradient for the month of January was used to demonstrate the application of the vertical refractivity profile models. From the result, the point refractivity gradient of Cross River state is 124.278 N-units in January.
Abstract: In this paper six months data on primary radioclimatic parameters obtained using Radiosunde lunched by Nigerian Meteorological Agency (NIMET) in Cross River state, Nigeria is used to model the vertical radio refractivity profile. Cross River state is located at 4°57’North in latitude and 8°19'East. For each of the six months, cubic trendline equati...
Show More
-
Mathematical Model for Equivalent Fresnel Zone Line of Sight Percentage Clearance for Terrestrial Point-to-Point Line-of-Sight Communication Link
Ikechukwu H. Ezeh,
Nwiido Friday,
Amlabu Runcie
Issue:
Volume 2, Issue 1, February 2017
Pages:
27-31
Received:
31 October 2016
Accepted:
12 January 2017
Published:
5 April 2017
DOI:
10.11648/j.wjap.20170201.14
Downloads:
Views:
Abstract: In this paper mathematical model for equivalent Fresnel zone line of sight percentage clearance for terrestrial point-to-point line-of-sight communication link is presented. Sample 3 GHz microwave link with 38887.6 m path length is used to demonstrate the application of the model. In the sample link, five Fresnel zones are considered, namely zone 1, 2 4, 8, and 16. The results show that at middle of the link, the corresponding radius of each of the five Fresnel zones are r1 = 31.18 m, r2=44.1m, r4=62.36m, r8=88.19 m, r16 =124.72 m. When the LOS percentage clearance specified with respect to Fresnel zone 1 is-100% the corresponding LOS percentage clearance with respect to the other Fresnel zones are as follows: Fresnel zone 2 is -70.71%, Fresnel zone 4 is -50%, Fresnel zone 8 is -35.36% and Fresnel zone 16 is -25%. The results confirm that the equivalent line of sight percentage clearance is given as Pc(x, n2) = 
where n1 and n2 are two different Fresnel zones and 
) are the line of sight percentage clearance at Fresnel zone n1 and n2 respectively.
Abstract: In this paper mathematical model for equivalent Fresnel zone line of sight percentage clearance for terrestrial point-to-point line-of-sight communication link is presented. Sample 3 GHz microwave link with 38887.6 m path length is used to demonstrate the application of the model. In the sample link, five Fresnel zones are considered, namely zone 1...
Show More
-
The Flight of the Balloon and the Daily Rotation of the Earth
Issue:
Volume 2, Issue 1, February 2017
Pages:
32-35
Received:
9 March 2017
Accepted:
20 March 2017
Published:
11 April 2017
DOI:
10.11648/j.wjap.20170201.15
Downloads:
Views:
Abstract: At the Earth’s surface acts the electromagnetic force, which distributes charges. Under the action of this force the positive charges move upward and the negative charges down. Here we tried to demonstrate the possible influence of this force on the flight of the balloon.
