ISSN: 1817-2695

Volume 37, Issue 3

Volume 37, Issue 3, Spring 2011, Page 1-71


The Chemisorption of Hydrogen Atom on solid surface and The Effect of External Magnetic Field

R. D. Al-Kafaaji; J. M. Al-Mukh

Journal of Basrah Researches (Sciences), Volume 37, Issue 3, Pages 1-12

The Chemisorptions of Hydrogen atom on tungsten surface is studied in this work . Our study has two mean goals , the first is to study the dependence of coupling term on the atomic energy levels occupation through out the chemisorptions process . The second is to study the chemisorptions process for the same system in the existence of external magnetic field . For this purpose extended model calculation has presented to calculate the atomic energy levels occupation numbers and all the related chemisorptions functions . The image and correlation effects are all taken into consideration . The localized states are also determined and calculated as well as their occupation numbers which taken into consideration in the chemisorptions energy calculation . Throughout our calculations , the general features of the system under consideration have investigated using physical initial conditions getting use of the coupling - occupation numbers dependence . Our calculations show two types of solutions from its ranges for coupling strength values are characterized . The first is weak coupling where the solution is magnetic with no localized states . The second is strong coupling where the solution is nonmagnetic with localized states . And for the second goal , the chemisorptions process for the system under consideration in the existence of external magnetic field is studied. Since the external field effect is added as shifts with finite values to the atomic levels . The atomic levels occupation numbers and the related chemisorptions functions , the localized states and this occupations and the energy are all calculated in the existence of the external field for the three coupling ranges . Discussion and important conclusions about the band width , the condition for the localized states existence , the image and the correlation effects ,are presented .

Numerical study of high dimensional Henon system

H. A. Sultan; and; Kahtan Adnan Hameed

Journal of Basrah Researches (Sciences), Volume 37, Issue 3, Pages 13-18

This paper presents the numerical study of a generelized Henon system to show various types of dynamical behaviors using time series, attractor's as well as the spectral distribution of the main
variable. Results indicated the generation of new types of attracters with severe instabilities.

Laser Field Effect on the Chemisorption Process of Diatomic molecule on Solid Surface

Jenan M. AL-Mukh; Maged A. Nattiq

Journal of Basrah Researches (Sciences), Volume 37, Issue 3, Pages 19-36

In this study ,a mathematical model to study the chemisorption of two interacting atoms on solid surface in the presence of laser field is presented . Our study has aim only , the study the effect of laser field on determining the ionization and dissociation states to describe the molecule – surface interaction dynamics . Our mathematical model is based on the occupation numbers formula that depends on the laser field and which is derived according to Anderson model for single atom adsorbed on solid surface. Occupation numbers formula and chemisorption energy formula are derived for two interacting atoms (as a diatomic molecule )as they approach to the surface taking into account the correlation effects on each atom and between atoms as well as the image effect on each one . This model is characterized by the obvious dependence of the relations on the system variables and the laser field characteristics which gives precise description for the molecule – surface interaction dynamics (i.e. the charge and spin on the interacting atoms ) as a function of the normal distance from the surface and the distance between atoms .Our mathematical model is applied to the H2/W(100) system for academic and experimental reasons, where the molecule- surface interaction dynamics is investigated by calculating the occupation numbers and all the chemisorption functions as a function of all variables when the distance between the atoms is parallel to the surface.It is found that the type of interaction between the atoms and surface , whether it is repulsive or attractive , is determined by the laser strength where the repulsion between the two atoms increases with the laser strength increasing . The orientation effects are taken into account throughout the broadening functions due to the coupling with surface energy levels and as well as due to the laser field.Extended calculations for all functions, that describe the system dynamics, are presented as a function of all variables as well as the orientation angle. By comparing the orientation effect and laser field effect, it is concluded that the laser field effect is dominant .It is found that by taking the orientation effects, the interaction is repulsive for both strength values that used (0.1a.u.,0.2a.u.) in this research as compared with the case of incorporating laser field only or orientation effect only. So it makes sure that the laser field as well as the orientation effects can be consider as a tool to control the ionization and dissociation processes that happen on the solid surface .

Comparative anatomical study of some genera of Polygonaceae

K. J. Hammadi; Iman M. AL-Rubaie; A. AL-Mayah

Journal of Basrah Researches (Sciences), Volume 37, Issue 3, Pages 37-45

Detailed of anatomical study of stem and petiole of ( 3 ) species of
Atraphaxis L. , ( 2 ) species of Calligonum L. , (1) spicies of Eme Neck
., (1) species of Fagopyrum Mill . , (1) species of Oxyria Hill. , ( 2 )
Species of Pteropyrum Jaub. & Spach . and ( 1 ) species of RheumL.
Present in Iraq were described .

The result showed that the anatomical characters of the stem such as stem outline , number of vascular bundles , size of pith , chlorenchyma , collenchyma and sclerenchyma tissues are of considerable taxonomic value at the specific or generic level and can be used for taxa separation .

The number of vascular bundles of petioles appeared vaiable between 6 to 8 in most species except Pteropyrum neoanum Boiss. ex.
Meisner which contain one central vascular bundle surrounded by
complete ring of tanniferous cells . All the petiols of species examined
have large numbers of drusses crystals except Fagopyrum esculentum
Moench

Bioaccumulation and effect of some heavy metals on worm Namalycastis indica (Annalida: Polychaeta)

Manal M. Akbar; Anaam M. Altaee; Hamid T. Al-Saad

Journal of Basrah Researches (Sciences), Volume 37, Issue 3, Pages 46-55

The present study was conducted to investigate the ability of the worm Namalycastis indica to accumulate some heavy metals in its tissues. The heavy metals measured were Cadmium (Cd), copper (Cu), nickel (Ni), and cobalt (Co) after the exposure period for (14) days. Further more the study included, the effect of these metals on the growth of N. indica. The worms were grown in media containing different concentrations of the above heavy metals. These concentrations ranged from (5 to 250) ppm. A flame atomic absorption spectrophotometer was used to measure the concentration of the heavy metals in the tissues of worm. The worms showed high ability to accumulate Cd, Ni, Cu and Co. An increase of heavy metals concentrations in the worm tissues were associated with the increase of these metals in media. The maximum concentration of Cd, Ni, Cu, and Co in the worm tissues were (28.31, 12.22, 22.63, 10.67) ppm respectively. At a concentration (250 ppm) in the media. Different concentrations of Ca, Ni, and Cu resulted significant loss of weight of the worms .The Co showed the lowest effect on weight decrease of the worms, compared with the other metals. It was also clear, the increasing effect of heavy metals on worms growth, with concentration increasing showed the maximum effect on weight loss Ca followed by Ni, Cu and Co, when worms grown in media contained (250 ppm) of the metals.

The inhibitory activity of Artemisia absinthium against some species of bacteria and fungi

Layla Nasser Harub; and; Sabriya Abd-Ali Mohammed

Journal of Basrah Researches (Sciences), Volume 37, Issue 3, Pages 56-62

In this study , the antimicrobial and antifungal effect of aqueous and alcoholic extracts of Artemisia absinthium were assayed against bacteria like Staphylococcus aureus , Escherichia coli, Pseudomonas aeruginosa , Proteus vulgaris and fungi like Aspergillus niger , Aspergillus terrus and Aspergillus fumigatus .
The result indicated that the alcoholic extract gave clear inhibitory activity against all the tests bacteria under concentration by the range of ( 20-30) mm but the aqueous extract gave inhibitory activity against S.aureus only , while both the extract don’t gave any inhibitory activity against fungi.

The MIC value was detirminated by the range from ( 50-150 ) mg/ml .

Histopathological effect of two different wavelengths of visible laser

Journal of Basrah Researches (Sciences), Volume 37, Issue 3, Pages 63-71

Laser light has special characteristics features compared to conventional light sources made it the prime source in different scientific disciplines . The present study confirmed that low level laser therapy (LLLT) can accelerate the wound healing process of skin by using two visible ( red 632.8 nm and green 532 nm ) light . The study included (90) mice regardless of sex divided into control (10 mice ) and study groups (80 mice). Injury to skin was done for both groups . The control group was left for healing without any interventions at usual conditions . The study ( treated ) group consisted of 80 mice divided into two groups (40 mice ) each . The first group subdivided to four small groups (10) mice each and were exposed to the wavelength 632.8 nm at two different energy densities . The second group was subdivided too by the same manner and exposed to the wavelength 532 nm at two different energy densities . Skin biopsy from the wounds was taken from all mice for histopathological study at ( 1,3,5,7) days of injury . The study revealed that laser acceleated inflammatory proliferative phases. The best results for healing wound at laser 632.8 nm at energy density of 0.708 J/cm2 while for the laser 532 nm was of 0.271 J/cm2 .