Polyimide/MWCNTs nanocomposites have been fabricated by solution mixing process. In the present study, we have investigated electrical conductivity and dielectric properties of PI/MWCNT nanocomposites in frequency range of 1 kHz to 100 kHz at different MWCNTs concentrations from 0 wt.% to 15 wt.%. It has been observed that the electrical conductivity and dielectric constants are enhanced significantly by several orders of magnitude up to 15 wt.% of MWCNTs content. The electrical conductivity increases as the frequency is increased, which can be attributed to high dislocation density near the interface. The rapid increase in the dielectric constant at a high MWCNTs content can be explained by the formation of a percolative path of the conducting network through the sample for a concentration corresponding to the percolation threshold. The high dielectric constant at a low frequency (1 kHz) is thought to originate from the space charge polarization mechanism. I-V characteristics of these devices indicate a significant increase in current with an increase in multi-walled carbon nanotube concentration in the composites. The SEM images show improved dispersion of MWCNTs in the PI matrix; this is due to the strong interfacial interactions.
This study presents the results of atmospheric particulates sampling using high volume air sampler for selected places at Al Tuwaitha nuclear site. The collected samples were analyzed for gross alpha /beta radioactivity using Ludlum model 3030 and measurement particles activity in Al Tuwaitha nuclear site and the surrounding areas for the period from 28/12/2016 to 13/4/2017.The measurement of activity concentrations ranged from (0.42±0.03 to 4.18±0.13) Bq/m3 for alpha particles and from(0.93±0.06 to 9.21±0.26) Bq/m3for beta particles. The activity concentration of nuclides inversely proportional with air temperature and wind speed while humidity is directly proportional with it. Highest value of activity concentration has been found at(
... Show MoreBackground: Alternative natural therapy by plants extracts had opened wide door for the use of natural products as an alternative therapy instead of many antibiotics and drugs , which had many harmful side effects.Also, an increased interest has been centered on the industrial wastes, especially plant raw materials which contain phenols (e.g. Pomegranate peel and Bay leaves) which is a sources of natural antioxidants ,which are on the contrary of synthetic antioxidants that had restrict use due to their health risks , carcinogenesis and toxicity .
Objectives :This study was done to fi
... Show MoreTwo main grand bus national stations in Baghdad ( Alawi-alhila and Bab-almudam) were chosen as examples to determine lead effect on its drivers. This lead came from ethyl tetra lead or ethyl tri lead which used to improve gasoline quality ,so these two stations could be consider as two of the most polluted places due to gasoline burned by hundreds cars located in these stations .The determination of environmental lead pollution was measured in blood and urines drivers. Drivers were divided in two main groups due to their ages ( 30 persons in each group). The first group for men of 22-30 years old. The second group for men of 40-60 years old. Those men were carefully chosen in order to be non-fumiers or non-alcoholics persons because of
... Show MoreThe Love Creek Nature Center, one of the three nature centers located within the boundaries of Berrien County, is owned and operated by the county for public enjoyment and instruction of nature. The 44.5 ha study area, located seven km east of Berrien Springs, and two km southwest of Berrien Center, on Huckleberry Road, in T6S, R17W, sections 16, 17 (Lat. 41° 56' N; Long. 86° 18' W) is made up of deciduous woods and abandoned fields at various stages of succession. It is bounded on the east by the Berrien County Dog Pound and Huckleberry Road, to the north by cultivated Berrien County land and the Berrien General Hospital, to the west by the recently closed Berrien - Oronoko Township Landfill Dump; and to the south b
... Show MoreIn this work, an estimation of the key rate of measurement-device-independent quantum key distribution (MDI-QKD) protocol in free space was performed. The examined free space links included satellite-earth downlink, uplink and intersatellite link. Various attenuation effects were considered such as diffraction, atmosphere, turbulence and the efficiency of the detection system. Two cases were tested: asymptotic case with infinite number of decoy states and one-decoy state case. The estimated key rate showed the possibility of applying MDI-QKD in earth-satellite and intersatellite links, offering longer single link distance to be covered.
4, 4s (pyridine 2, 6 diylbis (1, 3, 4 oxadiazole 5, 2 diyl)) bisphenol monomer (3) was synthesized from cyclization of Ns2, Ns6 bis (4 hydroxybenzylidene) pyridine 2, 6 dicarbohydrazide (2) in the presence of bromine in glacialacetic acid. Newly five polymers (P1P5) were synthesized from reaction bis 1, 3, 4 oxadiazole bisphenolmonomer with five different di acid chloride. The antibacterial activity of the synthesized polymers was screened against gram positive and gram negative bacteria. Polymers P4 and P5 exhibited significant antibacterial against all microorganisms, as well these polymers showed highest antifungal activity.
The research aimed to compare the performance of the commercial and the Islamic banks listed in the Palestinian's Stock Exchange .To achieve the objectives of the study we selected all the commercial and the Islamic banks listed in the Palestinian Stock Exchange to obtain the necessary data for the analysis process during the period of (2009-2013) .the comparison based on the performance indicators ( liquidity rate, profitability rate ,the activity rate and the market rate).
a statistical method was used to analyze the date to find the performance differences between the commercial banks,
... Show MoreAntioxidant status imbalance and inflammatory process are cooperative events involved in type 2 diabetes mellitus. This study aimed to investigate superoxide dismutase as a potential biomarkers of antioxidant imbalance, matrix-metaloprotinase-9, and interleukin -18 as biomarkers of inflammation in serum and to estimate the effects of other confounding factors gender, age and finally measuring the relation among the interested biomarkers.
This case - control study included 50 patients, and 45 of healthy subjects matched age –gender were also enrolled in this study as a control group. The focused  
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