A single-crystalline semi-polar gallium nitride (11-22) was grown on m-plane (10-10) sapphire substrate by metal organic chemical vapor deposition. Three-step approach was introduced to investigate the grain size evolution for semi-polar (11-22) GaN. Such approach was achieved due to the optimized gallium to ammonia ratio and temperature variations, which led to high quality (11-22) oriented gallium nitride epilayers. The full width at half maximum values along (-1-123) and (1-100) planes for the overgrowth temperature of 1080°C were found to be as low as 0.37° and 0.49°, respectively. This was an indication of the enhanced coalescence and reduction in root mean square roughness as seen by atomic force microscopy. Surface analysis via atomic force microscopy indicated the orientation towards semi-polar plane. Field emission scanning electron microscopy analysis further indicates that higher temperature of 1080°C during the deposition of the overgrowth promoted closely packed surface coalescence. Room temperature Raman revealed that the overgrowth temperature of 1080°C portrayed compressive strain free as compared to other overgrowth temperature. Based on these results, the promising overgrowth temperature of 1080°C can be further utilized in future work for optoelectronics devices.
The present study was conducted in the nursery of Floriculture Unit, University of Baghdad in Iraq during September to December of 2013. Vernalized bulbs of hybrid lily cultivars were imported from the Netherlands. The experiments were included some hybrid lily cultivars which represent the main groups of lily (longiflorum hybrids, Asiatic hybrid and trumpet hybrids). The three lily cultivars named as Tiger (Oriental), Brunello (Asiatic) and White Heaven (Longiflorum) were sprayed two times, at five weeks after planting and at eight weeks after planting with a solution of Cycocel (100 mg /l), solution of Indole butyric acid (50 mg/l) and Benzyl adenine (50 mg /l). The results indicated that foliar spray with IBA lead to decrease in flowe
... Show More"In this article, "we introduce the concept of a WE-Prime submodule", as a stronger form of a weakly prime submodule". "And as a "generalization of WE-Prime submodule", we introduce the concept of WE-Semi-Prime submodule, which is also a stronger form of a weakly semi-prime submodule". "Various basic properties of these two concepts are discussed. Furthermore, the relationships between "WE-Prime submodules and weakly prime submodules" and studied". "On the other hand the relation between "WE-Prime submodules and WE-Semi-Prime submodules" are consider". "Also" the relation of "WE-Sime-Prime submodules and weakly semi-prime submodules" are explained. Behind that, some characterizations of these concepts are investigated".
... Show MoreIn order to evaluate the effect of seed size, plant growth regulators and some chemical materials on seed vigour and seedling growth of rice (Oryza sativa L.) an experiment was conducted in 2015 at Laboratories of Agriculture and Marshes College, University of Thi-Qar. Factorial experiment in CRD was used with four replications in two factors. The first factor included three seed sizes (4.6-5.1, 5.2-5.7 and 5.8-6.3 mm). The second factor was seeds soaking treatments (KNO3 6 gl-1, CaCl2 20 gl-1, salicylic acid 20 mg l-1, cytokinin 40 mg l-1, gibberllic acid 400 mg l-1, ascorbic acid 40 mg l-1 and seeds soaked in distilled water). The results showed that the largest seed size influenced significantly and gave the higher averages of germinatio
... Show MoreFree radicals are reactive compounds, their excessive production is considered to be an important cause of oxidative damage in biomolecules causing degenerative diseases. Polyphenols are one of the most important groups of secondary metabolites of plants, which have an antioxidant activity depending on their properties as hydrogen donors. Echinops polyceras Boiss. (Asteraceae) is one of Echinops genus species that spread in Syria, Lebanon, and Palestine. Phytochemicals found in this species leaves have been extracted with gradient polarity solvents, and primary screening of the secondary metabolites was established. The phenolic compounds and flavonoids contents were determined. The free radicals scavenging activity was evaluated for all
... Show MoreThe present work included new information about pollen of eighteen Spp. of Stachys L. in Iraq ;showed their importance in diagnostsis.
Pollen shapes in equatorial view were ellipsoid in most spp .and spherical - subspherical , spherical - subprolate and subprolate -
ellipsoid in others; while they were spherical - subspherical in polar
view . Pollen was tricolpate except St.iberica M.B.georgica Rech.f. &
Ten. Which has tetracolpate and that was new for the genus.
The smallest pollen were seen in St.kotschyi Boiss. & Hohen. but the biggest were in St.benthamiana Boiss.
This experiment was conducted in the orchard of the Department of Horticulture,college of Agriculture,Baghdad University during the growing season of 2007 To study the effects of spray with three concentration of cultar(0,500,1000 mg.L-1) ,tow concentration of K2SO4(0,5g.L-1), and salinity of irrigation water with three concentration (1,2,3dS.m-1) on some characteristics of vegetative growth of two cultivars of apricot trees (Labib1 and Zienni).The age of trees was four years .The tree grafted on original of seed apricot . Afactorial trail was carry out according to randomized complete block design with arrangement of split-split with three replications. Salinity of irrigation water took main plot, potassium took sub plot and cultar took s
... Show MoreFree radicals are reactive compounds, their excessive production is considered to be an important cause of oxidative damage in biomolecules causing degenerative diseases. Polyphenols are one of the most important groups of secondary metabolites of plants, which have an antioxidant activity depending on their properties as hydrogen donors. Echinops polyceras Boiss. (Asteraceae) is one of Echinops genus species that spread in Syria, Lebanon, and Palestine. Phytochemicals found in this species leaves have been extracted with gradient polarity solvents, and primary screening of the secondary metabolites was established. The phenolic compounds and flavonoids contents were determined. The free radicals scavenging act
... Show MoreWe introduce in this paper the concept of approximaitly semi-prime submodules of unitary left -module over a commutative ring with identity as a generalization of a prime submodules and semi-prime submodules, also generalization of quasi-prime submodules and approximaitly prime submodules. Various basic properties of an approximaitly semi-prime submodules are discussed, where a proper submodule of an -module is called an approximaitly semi-prime submodule of , if whenever , where , and , implies that . Furthermore the behaviors of approximaitly semi-prime submodule in some classes of modules are studied. On the other hand several characterizations of this concept are
... Show MoreTitanium alloy (Ti-6Al-4V or Gr.23) was widely used as a dental alloy. In the current study, polymerization of eugenol (PE) on Gr.23 titanium alloys was conducted by an electrochemical process before and after being treated by Micro Arc Oxidation (MAO). The formed films were characterized by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDS), and X-ray diffraction (XRD). The corrosion behavior of Gr.23 alloy in an artificial saliva environment at a temperature range of 293–323 K has been studied and assessed by means of electrochemical polarization and impedance spectroscopy techniques. Three cases are taken into consideration; bare Gr.23, Gr.23 coated by PE, and Gr.23 coated by PE after MAO treatment. The maxi
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