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.
Corrosion rate tests were carried out on carbon steel under concentration cells conditions of oxygen and sodium chloride. The effect of aeration in one compartment on the corrosion rate of both coupled metals was determined. In addition, the effects of time and temperatures on the corrosion rate of both coupled metals and galvanic currents between them were investigated. Corrosion potentials for the whole range of operating conditions under concentration cell conditions were also studied. The results showed that under aeration condition, the formation of concentration cell caused a considerable corrosion rate of the Carbon steel specimens coupled in different concentrations of O2 and NaCl due to the galvanic effect
... Show MoreBackground: Male infertility is a global concern and it tends to increase due to miscellaneous factors, such as environmental toxins and genetic and lifestyle choices. The aryl hydrocarbon receptor (AHR) has recently attracted attention due to its involvement in male infertility mechanisms and impact on sperm production and function. AHR, a versatile receptor expressed in various tissues, including the testes, regulates the genes involved in spermatogenesis. AHR activation is associated with cell cycle regulation and chromatin condensation during spermatogenesis. Objectives: This study aimed to investigate the influence of AHR activation on blood-testis barrier (BTB) integrity, focusing on the role of tight junction protein-1 (TJP1)
... Show MoreBackground: To investigate the effect of different types of storage media on enamel surface microstructure of avulsed teeth by using atomic force microscope.Materials and methods : Twelve teeth blocks from freshly extracted premolars for orthodontic treatment were selected . The study samples were divided into three groups according to type of storage media :A-egg white , B- probiotic yogurt , and C-bovine milk . All the samples were examined for changes in surface roughness and surface granularity distribution using atomic force microscope, at two periods: baseline, and after 8 hours of immersing in the three types of storage media. Results: Milk group had showed a significant increase in the mean of the roughness values at
... Show MoreIn this work, the copper metal was treated using Nd:YAG laser with energy 1Joul to enhance corrosion resistance and improve surface properties. The copper metal has many applications in industry as well as water, oil and gas pipes. The same conditions, (laser power density, scan speed, distance between paths, medium gas-air) were applied in the laser surface treatment, After laser treatment, the samples microstructures were investigated using optical microscope (OM) to examine micro structural changes due to laser irradiation. Specimen surfaces were investigated using atomic force microscopy (AFM), X-ray diffraction (XRD), macro hardness, and corrosion test before and after laser treatment to
... Show MoreBackground: The undergraduate students in pharmacy colleges represent a well-educated group of thecommunity according to the use of drugs and they are required to hold the appropriate knowledge of druguse and have positive attitudes toward health problems, this good knowledge about the diseases and theirtreatment will give good pharmacists in the future and this will reflect positively on patient knowledge, andtheir compliance with treatment, this due to direct contact of pharmacists with the patients.Aim: To know the knowledge, Awareness and Attitude of a sample of Iraqi pharmacy students towardsepilepsy.Method: Cross-sectional study used a structured questionnaire validated by previous studies to collectdata about knowledge, Aware
... Show MoreNations witnessed since its existence a state of wills conflict as a result of the intersection and intertwining of interests, through which it sought to achieve its goals and objectives, and this has often led to direct military conflicts and countless wars, and witnessed the entry into global wars in which humanity lost millions of lives and losses .Despite the great changes in the international arena, especially in recent decades, the conflict of wills has not ceased, although some of its features and forms have changed, and it has become more complicated after the withdrawal of this conflict to international organizations and bodies, including the Security Council. It is mandated under the Charter of the United Nations to wor
... Show MoreFourteen morphologically varied Ricinus communis L. seeds were collected from different localities in Egypt, El-Sudan and Saudi Arabia. Seed morphology and ITS barcoding analysis were performed to assess their diversity and phylogenetic relationship. Sequence’s alignment of nrITS region from different accessions display high levels of genetic similarities. Cluster analysis could not group different accessions according to their geographical distribution. Nevertheless, the genetic barcodes are interestingly matched with the morphological features of the Ricinus seeds. In conclusion, seed morphology proved to be a valuable tool in evaluating biodiversity and phylogenetic relationship in plant species with different loca
... Show MoreBackground: Polycystic ovary syndrome is among the leading causes of fertility-related problems and menstrual irregularities in women of reproductive age. The granulosa cells of the developing pre-antral and antral follicles produce inhibin B, which triggers chemical responses in the ovaries. Inhibin B is most often observed in the follicular phase when levels peak early and then decline over time Objectives: This study was designed to investigate the role of serum inhibin B and the Luteinizing Hormone / Follicle Stimulating Hormone ratio in differentiation between the different phenotypes of polycystic ovary syndrome as well as to define the predominant PCOS phenotype. Methods: This cross-sectional research was conducted in the
... Show MoreThis research deals with deliberative intentionality in its two dimensions, deliberative intent, direct, and indirect deliberative intent, and deliberative intentionality assumed great importance to ancient and contemporary scholars. The text, relying on deliberative intent as a methodology concerned with the study of language in usage, and the research focuses on direct deliberative intent through (the intent of acceptability, the intent of the presumption, the intent of the informational, the intent of interaction), and the indirect deliberative intent through (the intentionality of the case, the intent of the metaphor, The intent of the communicative impulse, the intent of the allusion,), and these deliberative elements activate and c
... Show MoreThe regression analysis process is used to study and predicate the surface response by using the design of experiment (DOE) as well as roughness calculation through developing a mathematical model. In this study; response surface methodology and the particular solution technique are used. Design of experiment used a series of the structured statistical analytic approach to investigate the relationship between some parameters and their responses. Surface roughness is one of the important parameters which play an important role. Also, its found that the cutting speed can result in small effects on surface roughness. This work is focusing on all considerations to make interaction between the parameters (position of influenc
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