In this work, the effects of size, and temperature on the linear and nonlinear optical properties in InGaN/GaN inverse parabolic and triangular quantum wells (IPQW and ITQW) for different concentrations at the well center were theoretically investigated. The indium concentrations at the barriers were fixed to be always xmax = 0.2. The energy levels and their associated wave functions are computed within the effective mass approximation. The expressions of optical properties are obtained analytically by using the compact density-matrix approach. The linear, nonlinear, and total absorption coefficients depending on the In concentrations at the well center are investigated as a function of the incident photon energy for different values of temperature and quantum wells size. The results show that the In concentrations, size and temperature have a significant effect on these optical properties. The positions of the resonance peaks of the absorption coefficients were blue-shifted under increasing indium compositions in the quantum wells (InGaN) and temperature while they were red-shifted with the increase in the thickness of the wells. Moreover, the amplitudes of the resonance peaks were enhanced under the increase of the In composition, the temperature, and the thickness of the quantum wells. The optical absorption in ITQW structure is slightly greater than that in IPQW one.
An extensive survey of citrus leaf miner (CLM) , Phyllocnistis citrella Stainton parasites
and predators was conducted during 1998 and 1999 in citrus orchards and nursuries in
Baghdad, Diyala and Wasit .Five eulophid parasites were recorded for the first time on citrus
leaf miner larvae , prepupae and pupae viz. Cirrospilus sp, Pnigalio sp ., Ratzburgiola
incompleta , Tetrasticus sp. and, Neochrysocharis formosa . Parasitism rate was ranged from
15% to 63% Chrysopa carnea , Orius albidipennis , Amblyseius sp . Were observed as
predators on CLM .
The study aimed to assess the expression of CD49d and CD26 in newly diagnosed CLL patients and find their correlation with clinical Binet stage, and other clinical parameters. This study was conducted on 51 newly diagnosed CLL patients based on lymphocyte count > 5×109/L and immunophenotyping. The expression of CD49d, and CD26 were investigated using eight-color flow cytometer. The expression of CD49d and CD26 were detected in 56.9 %, 68.8 % of CLL patients, respectively. The correlation between CD49d expression and CD26 expression was statistically significant (p < 0.001) with high concordance rate between them. The positive expression of both CD49d and CD26 had statistically significant association with clinical Binet staging (p < 0.001,
... Show MoreThe research focuses on how to reach a mechanism that assists experts, engineers, and others in the architectural & engineering project to verify the co-existence of values and sustainability constituents in it. Research problem shows a clear lack, locally, in the interest to establish a value system and a list that cares about comprehending building components whether considering sustainable building criteria. Hypothesis shows that in order to head towards the applicable sustainable approach of buildings, then a local assessment system should be established to evaluate buildings during its life cycle, and from which buildings would be categorized as sustainable or not. Research aims at establishing main and general
... Show MoreThis research concern to analyse and simulate the temperature distribution in the spot welding joints using tungsten arc welding shielded with inert gas (TIG Spot) for the aluminum-magnesium alloy type (5052-O).
The effect of and the quantity of the heat input that enter the weld zone has been investigated welding current, welding time and arc length on temperature distribution. The finite element method (by utilizing programme ANSYS 5.4) is presented the temperature distribution in a circular weld pool and the weld pool penetration (depth of welding) through the top sheet ,across the interface into the lower sheet forming a weld spot. &nbs
... Show MoreBackground: Preeclampsia (PE) is a major cause of maternal morbidity and mortality, complicating 3-14% of all pregnancies. Although the etiology remains unknown, placental hypoperfusion and diffuse endothelial cell injury are considered to be the central pathological process; many endocrinological changes have been linked to the etiology of preeclampsia including parathyroid hormone and calcium level. Objective: to compare serum parathyroid hormone and total serum calcium levels in mild and severe preeclampsia versus normal pregnancy. Patients and methods: Serum parathyroid hormone (PTH) level and total serum calcium level were measured in thirty normotensive pregnant women and thirty women with mild preeclampsia and thi
... Show MoreNumerical Investigation was done for steady state laminar mixed convection and thermally and hydrodynamic fully developed flow through horizontal rectangular duct including circular core with two cases of time periodic boundary condition, first case on the rectangular wall while keeping core wall constant and other on both the rectangular duct and core walls. The used governing equations are continuity momentum and energy equations. These equations are normalized and solved using the Vorticity-Stream function and the Body Fitted Coordinates (B.F.C.) methods. The Finite Difference approach with the Line Successive Over Relaxation (LSOR) method is used to obtain all the computational results the (B.F.C.) method is used to generate th
... Show MoreThis study was carried out from February to October 2012 in six semi salty ponds in Gwer sub-district which is the first work in the area. A total of 32 species and 2 genera of algae where reported as the new records. Mostly the non diatoms are belonging to Cyanophyta, Chlorophyta, Euglenophyta, Cryptophyta, Chrysophyceae, while diatoms or Bacilariophyceae are belong to pennals- order.
The heat transfer and flow resistance characteristics for air flow cross over circular finned tube heat exchanger has been studied numerically and experimentally. The purpose of the study was to improve the heat transfer characteristics of an annular finned-tube heat exchanger for better performance. The study has concentrated on the effect of the number of perforations and perforations shapes on the heat transfer and pressure drop across a staggered finned tube heat exchanger. The Numerical part of present study has been performed using ANSYS Fluent 14.5 using SST Turbulent model, while the experimental study consist from a test rig with different models of heat exchangers and all required measurement devices were build
... Show MoreJatropha L. is an exotic genus to Iraq and it has been cultivated in gardens for ornamental purposes because of the shiny red color of the flowers. The plant adapted to environmental conditions and succeeded in growing and blooming, which is why the species was interested to study. The species Jatropha integerrima Jacq. was examined and diagnosed for the first time in Iraq. Morphological and anatomical characteristics for leaves (considering that the variations are the most reliable and taxonomically important) were provided. The Phytochemical screening showed the presence of alkaloids, flavonoids, terpenes, tannins and saponins. The qualitative analysis by TLC indicated the presence of alkaloids and flavonoid that was detected by specia
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