A high Tc superconductor with a nominal composition
(Bi1-xPbx)2(Sr1-yBay)2Ca2Cu3O10+δ for (0 £ x £ 0.5) and (0 £ y £ 0.5) was prepared by
a solid state reaction method. The effect of the substitution of Pb for Bi and Ba for Sr and
quenching temperature on the superconductivity has been investigated to obtain the
optimum conditions for the formation and stabilization of the high Tc phase (2223).
The results showed that the optimum sintering temperature for the pure composition is
equal to 875°C and the sintering time is equal to 240h with heating and cooling rate of
60°C/h . Our results indicated that a small amount of (Ba = 0.1) could raise the transition
temperature (Tc), but enhancing Ba to 0.4 has raised the resistivity and the behavior of the
composition converted to semiconductor and ultimately for the composition that has (x =
0.4, y = 0.5) was an insulator. The best value of (Tc = 122 K) is for the composition that
has x = 0.2, y = 0.1.On the other side for Ba free samples increasing of lead content up to
0.3 has rise the transition temperature (Tc = 116 K) but more increases to (0.4, 0.5) causes
a decrease in Tc.
The effect of quenching temperature Tq on the transition temperature Tc of the (Bi1-
xPbx)2(Sr1-yBay)2Ca2Cu3O10+δ was also investigated .
The current study was conducted to determine the sensitivity of some pathogenic bacterial isolates isolated from wounds and burns water toward the disposer of the Yas Rue tested five crude bacterial isolates isolated from wounds and burns which these isolates sensitive to aqueous extract crude
Background: This study was formulated to compare the effect of 5%hydrofluoric acid in comparison to 37%phosphoric acid with and without the application of silane on bond strength of composite to porcelain. Materials and Methods: Specimen preparation was divided in to two phases, metal-disks fabrication (8mm-diameter and 4mm-thickness) and ceramic veneering. Thirty two specimens were prepared, sandblasted with 50 μm aluminum oxide, and divided into four groups of eight samples. Groups I and III were etched with 37%phosphoric acid while groups II and IV were etched with 5%hydrofluoric acid; and groups I and II were silaneted while groups III and IV were not. Heliobond, and resin composite were applied to each specimen using a plastic transpa
... Show MoreThe present study includes the effect of the ethanolic and aqueous extract of Piper nigrum against the third instar of Culex pipiens molestus (Diptera:Culicidae) in different concentrations: 1, 1.5 ppm of ethanolic extracts of Piper nigrum causing 100% mortality of larvae in the second day of treatment, while the concentrations 5% of aqueous extracts of Piper nigrum caused 100% mortality of larvae in the second day of treatment. The concentration 2.5% caused 100% mortality of larvae after four days of treatment. The current study also detected the effect of 0.1% concentration of Piper nigrum aqueous extract. The effect of this concentratio
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In this study, the effect of Nd: YAG laser on the activity of superoxide dismutase (SOD) and alcoholdehydrogenase (ADH) was investigated. The Saccharomyces cells were irradiated using 532nm Q-Switched Nd: YAG laser with (1Hz) frequency. Different fluences 11.3, 22.6 and 33.9mJ/cm2 and different number of pulses 15, 30 and 60 pulse were used. The irradiated cells were incubated in a liquid nutritive medium for 24 hours. After incubation, the cells were harvested and disrupted to extract the intracellular enzymes and their activities were assessed. In comparison with the control, the irradiated cells showed a significant increase in the activity and the specific activity of SOD at energy densities of 11.3 and 22.6mJ/cm2 at 30 and 60 pulses
... Show Morebackground: human epidermal growth factor receptor-2 (her2/neu) is related to growth factor receptors with alkaline kinase activity and it is regarded as important prognostic and therapeutic factor that can depended on in breast cancer therapy. HER2/neu expression by immunohistochemistry (IHC) is submitted to a great in terob server inconsistency. Subsequently additional confirmatory tests for assessment of gene alterations and amplification status are needed for patients with early or metastatic breast cancer. In situ hybridization techniques and specifically Chromogenic in situ hybridization (CISH) was arise as a practical, cost-effective, and alternative to fluorescent in situ hybridization in testing for gene alterationAims of the study
... Show MoreCoronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a pandemic worldwide. On a daily basis the number of deaths associated with COVID-19 is rapidly increasing. The main transmission route of SARS-CoV-2 is through the air (airborne transmission). This review details the airborne transmission of SARS-CoV-2, the aerodynamics, and different modes of transmission (e.g. droplets, droplet nuclei, and aerosol particles). SARS-CoV-2 can be transmitted by an infected person during activities such as expiration, coughing, sneezing, and talking. During such activities and some medical procedures, aerosols and droplets contaminated with SARS-CoV-2 particles are formed. Depending on their
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Chlorine doped SnS have been prepared utilizing chemical spray pyrolysis. The effects of chlorine concentration on the optical constants were studied. It was seen that the transmittance decreased with doping, while reflectance, refractive index, extinction coefficient, real and imaginary parts of dielectric constant were increased as the doping percentage increased. The results show also that the skin depth decrease as the chlorine percentage increased which could be assure that it is transmittance related.
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Background: Squamous cell carcinoma is a disease of elderly peopleand it is uncommon in people with less than 40 years old; however many literatures revealed that tumor developing in patients younger than forty years appears more aggressive at the time of diagnosis. The purpose of the present study was to focus on the clincopathological features of the oral SCC in different age groups. Material and methods: In this study thirty five cases of paraffin embedded tissue blocks of oral squamous cell carcinoma were studied. The age range was from 16 to 80 years. The clinicopathological data were recorded for evaluating the tumor characters according to age of patients. Results : The age was not significantly correlated to the clinicopathological
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