In this work Polyynes was synthesized by pulse laser ablation of graphite target in ethanol solution. UV-Visible Spectrophotometer, Fourier Transform Infrared Spectroscopy (FTIR) and Transmission electron microscopy (TEM) were used to study the optical absorption, chemical bonding, particle size and the morphology. UV absorption peaks coincide with the electronic transitions corresponding to linear hydrogen – capped polyyne (Cn+1H2), the absorption peaks intensity increased when the polyynes were produced at different laser energies and the formation rats of polyynes increased with the increasing of laser pulse number. The FTIR absorption peak at 2368.4 cm-1, 1640.0 cm-1 and 1276.8 cm-1 stretching vibration bond, were refer to the C ≡ C, C = C and C-C, respectively. A bond suggests the formation carbon nanoparticles suspend in this solvent and the TEM show the formation of spherical nanoparticles with size ranges from (1.2 to 105.9 nm) and aggregation of the carbon nanoparticles.
Abstract:
The internal control is the tool through which it is possible to verify and ensure the implementation of tasks in accordance with the established plans and programs and to evaluate the level of performance that is implemented within the different companies.
A guarantee from the supplier with the absence of a specialized technical committee that follows up the stages of implementing the contract and disbursing all amounts of financial dues to the supplier before completing the implementation of the contract and overlooking the non-implementation of some clauses of the contract by the committee in charge of
... Show MoreThis research aimed at identifying the factors that affecting in the recruitment of a teaching staff for the Massive Open Online Courses (MOOCs) in university teaching at the University of Khartoum. The descriptive method was followed. The questionnaire was used as a tool for data collection,, which was distributed directly to a sample of (181) respondent of the teaching staff members of the senate at University of Khartoum from those who were attend at the senate meeting No. (409) which was held on 22 August 2016 Of (272). The researcher followed for the distribution the chance method, where each questionnaire was distributed to each of a teaching staff from different faculties at the University of Khartoum, according to his willingness
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Abstract
Personality is one of the most important elements that should be developed in university student. Thus, we have to develop the positive traits and neutralize the negative traits of students as well as we have to pay attention to the level of student achievement at the same time, the researcher designed a scale to measure the traits of study sample. The research come out with a number of recommendations and proposals, the most important of which Enhancing the positive characteristics of university students in order to reach them to the level of mature personality with mental health. Enhancing the positive role of the high level of achievement by motivating the stude
... Show MoreIt is well known that the rate of penetration is a key function for drilling engineers since it is directly related to the final well cost, thus reducing the non-productive time is a target of interest for all oil companies by optimizing the drilling processes or drilling parameters. These drilling parameters include mechanical (RPM, WOB, flow rate, SPP, torque and hook load) and travel transit time. The big challenge prediction is the complex interconnection between the drilling parameters so artificial intelligence techniques have been conducted in this study to predict ROP using operational drilling parameters and formation characteristics. In the current study, three AI techniques have been used which are neural network, fuzzy i
... Show MoreObjective: In order to evaluate the effect of different typed of Separating Medium on the roughness of the fitted
tissue surface of acrylic denture base.
Methodology: Chosen three types of separating medium (Group A Tin foil), (Group B Detery Isolant),(Group C
Cold Mould Seal),used 30 samples of hot cure acrylic resin ,10 samples for each group, after complete curing of
these samples , Profilometer device was used to measure the surface roughness of each sample in all groups.
Results: Using One Way ANOVA Test and LSD test, the results were highly significant in differences among all
groups. Although (Group A) showing lest roughness, (Group B) showing a satisfactory result of roughness, While
(Group C) Showing the hig
Amebiasis, related to the pathogenic parasite Entamoeba histolytica, is a prominent cause of diarrhea globally. Amebiasis is primarily a disease of impoverished communities in developing nations, although it has recently arisen as a significant infection among returning tourists and immigrants. Severe cases are linked to a high case fatality rate. Although polymerase chain reaction (PCR)-based diagnosis is becoming more widely available, it is still underutilized. Treatment with nitroimidazoles is now suggested, however novel parasite medication research is a top priority. To avoid problems, amebiasis should be considered before corticosteroid therapy. Because there is no effective vaccination, sanitation and availability to clean w
... Show MoreThe purpose of this study was to examine the histological structure of the kidney in snake Eryx gaculus gaculus. In present study, the snakes were collected from the city of Baghdad and transferred to the laboratory where their kidneys were dissected out. The samples were then processed to be prepared for histological examination microscopial observations showed that there is no border between the cortex and medulla regions of kidney. The kidney consists of nephrons which are composed of glomerulus surrounded by Bowman’s capsule; the other segments are proximal tubule, distal tubule and connecting tubule. The epithelial tissue lining of these segments simple cuboidal tissue.
The research attempts to identify the pattern of punctuation in contemporary Iraqi poetry through delving into the poetry of an Iraqi poet belonging to the seventieth generation, Namik Abdul Deeb, who belongs to the poets of Arab modernity in general, the research has reached many results, including that the signs of deletion were vocabulary marks any They are located in the center of the poetic singular, or inline markers, which are those that fall within the poetic line of the prose poem separating its vocabulary, or cross-sectional marks located within the poetic passages that are part of the poetic text, and finally text marks which are located within the poetic text and fragmented into Parts. The research also found that the work of
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