ISSN: 1817-2695

Volume 37, Issue 1

Volume 37, Issue 1, Winter 2011, Page 1-69

The cavity perturbation method for the measurement of the dielectric properties of (polystyrene/carbon black) composite

Raad A. Abdulnabi

Journal of Basrah Researches (Sciences), Volume 37, Issue 1, Pages 1-7

The cavity perturbation method has been used to measure the dielectric constant and loss factor of (polystyrene/carbon black) composites of different concentrations of carbon black fillers (5 wt% - 20 wt%) . The used cavity is rectangular in shape that exited the dominant mode (TE101) with a theoretical resonance frequency of about (9.7757 GHz). The composite having (20 wt%) carbon black fillers shows higher values of the dielectric constant ( ) and loss tangent ( ). Finally composites are very useful for electromagnetic shielding (SE) and radar absorbing materials (RAM).In general ,in case of the heterogeneous mixture, the behavior of the dielectric constant and loss tangent is found to increase with the increase of carbon black(CB) fillers.

Dynamical Delay Normalize of Master Equations Model of

R. M. Hassan; Prof.Dr. C. A. Emshary; Prof.Dr. S. I. Easa; and

Journal of Basrah Researches (Sciences), Volume 37, Issue 1, Pages 8-26

By re-expressing of the master equations model of quantum dots (QDs) laser theory by C. Gies (2007), we have added a dynamical delay factor to the s-shall population’s equations to take into account the retardation procedure. This addition has led to theoretical results nearly in isomorphism with experimental data . We present a theoretical simulation of characteristics and the turn-on dynamics of InGaAs/GaAs semiconductor QD laser output lasing with CW wavelength of 1.3μm at room-temperature including the photon-assisted polarization contribution.

Unbalanced multivariate repeated measurements with a Kronecker product structured covariance matrix

Rana Rony Faik; Assist.Prof.Dr.Abdul Hussein Saber AL-Mouel

Journal of Basrah Researches (Sciences), Volume 37, Issue 1, Pages 27-31

In this article we consider a set of repeated measurements on p variables on each of the n individuals. Thus, data on each individual is unbalanced data. The n individuals themselves may be divided and randomly assigned to g groups. We test the usual hypotheses and studied the likehood ratio test of this test ,assuming that the data on an individual has a covariance matrix which is a Kronecker product of two positive definite matrices.

Analysis of variance and covariance Repeated Measurement Model

Rana Rony Faik; Renna Dawood; and; Huda Zeki Naji

Journal of Basrah Researches (Sciences), Volume 37, Issue 1, Pages 32-38

In this article we consider one-way Multivariate repeated measurements analysis of covariance model (MRM ANCOVA), which contains one between-units factor (Group with q levels) ,one within-units factor (Time with p levels) and one covariate ( ) . For this model the covariate is time-independent, that is measured only once . The test statistics of various hypotheses on between-unites factors, within-units factors and the interaction between them are given.

Isolation , the purification and the identification of Hepatotoxin Microcystin-LR from two cyanobacterial species and studying biological activity on some aquatic organisms

Emad Y. A. Al-Sultan

Journal of Basrah Researches (Sciences), Volume 37, Issue 1, Pages 39-57

The study was included the isolation , the purification and the cultivation two cyanobacterial species isolated from AL-Khandaq river , Basrah city/ southern of Iraq represented by species Nostoc muscurum ( Agardh) and Anabaena variabilis ( kuetz.) in addition to green algae ( non- toxic alga) Chlorella vulgaris Beijerinck with measuring their growth constant ( K ) and generation time ( G ) . This study showed that the ability of two cyanobacterial species to produce toxins type hepatotoxins ( Microcystin-LR ) as the first time in Iraq especially for the two types above. Hepatotoxin was identified after the extraction and the purification by using HPLC technique ( High performance liquid chromatography ) to detect the purity and the concentration of this toxin , in addition Infra-red technique was used to investigate chemical active groups of hepatotoxoins. The Concentration of hepatotoxins reached to 28.57 µg/ml for alga N. muscurum and 4.61 µg/ml for species A. variabilis respectively . The two cyanobacterial species were used as food for three economic fish larvae represented by Cyprinus carpio L., Hypophthalmicthyes molitrix VaL. and Ctenopharyngodon idella Val. The results showed significant decreasing in mean of weight , length and survival percentage for all fish larvae when fed on toxic species compared with fed on non- toxic species C. vulgaris . Also the results showed toxic effect of two cyanobacterial species on some zooplankton species represented by Artemia salina , Daphnia magna and Brachionus calyciflorous after fed on toxic species . This feeding led to significantly decreasing p≤ 0.05 in the mean numbers of zooplankton compared with those fed on non- toxic microalga C. vulgaris .

- Studying the relationship between oxidative stress malondialdehyde and ß-carotene in the serum of asthmatic patients in Basrah Governorate-Iraq

S. Gh. Sayyah

Journal of Basrah Researches (Sciences), Volume 37, Issue 1, Pages 58-69

The present study was designed to evaluate the relationship between ß-carotene as antioxidant with malondialdehyde (oxidative stress) in the serum of asthmatic patients. In this study, a total number of (50) asthmatic patients (24 males, 26 females) visiting Allergic and Asthma Medical Center in Basrah city were involved and according to age, sex, severity, smoking and family history. From each patient serum blood samples were collected to estimate the malondialdehyde (MDA) and ß-carotene. In addition, (50) healthy subjects were investigated as a control group. We found that a highly significant increase lipid peroxidation measured as MDA (p< 0.01) for all asthmatic patients as compared to healthy control.
Also the (MDA) serum level increases significantly (p< 0.05) with age and severity, while a highly significant (p< 0.01) is with smoker patients and positive family history. The study also revealed a statistically significant decrease (p< 0.01) in ß-carotene serum level in all asthmatic patients as compared to healthy control. In regard to age and severity, serum ß-carotene level decreased significantly (p< 0.05) while with smoker patients and positive family history a highly significant decrease (p< 0.01). There were no significant changes in the (MDA) and ß-carotene levels between male and female patients. Moreover, a negative correlation was also observed between ß-carotene with (MDA) level in the patient group with these variables.
In conclusion, asthmatic patients suffer a high degree of reactive oxygen species (ROS) formation causing considerable oxidative stress indicated by high level oxidant (MDA) and low level of the antioxidant ß-carotene.