The effect of adding different volume of coumarin dye (5, 15, 25 and 35) ml on optical properties of Poly (Methyl Meth Acrylate) was studied. Films of pure PMMA and PMMA with different volume of coumarin dye (5, 15, 25 and 35) ml were prepared using the casting technique. Transmission and absorption of the films were measured by using UV-VIS spectrometer technique type (100 Conc), in order to assess the type of transmission which was found an indirect transition. An optical energy gap of pure PMMA is (4.95e v) and after adding coumarin with volume (25, 35) ml, the energy gap for PMMA decrease by (0.05) compere to pure PMMA films and addition energy gap appear equal to (4.1 e v). It was found that the absorption coefficient, extinction coefficient and dielectric constants increasing by addition coumarin.
Augmented reality technology is a modern technique used in all fields, including: medicine, engineering and education, and has received attention from officials in the educational process at present; The focus of this research is on the degree of use of augmented reality among field experience students in the project's optimal investment program for teaching staff and their difficulties, applied to a sample of 75 students, through a questionnaire prepared by the researcher as a tool to determine the degree of use, as well as difficulties. The researcher addressed the subject through two main axes to determine the degree of use, as well as the difficulties preventing teachers and learners from using this technique. The results of the rese
... Show MoreIn this ˑwork, we present theˑ notion of the ˑgraph for a KU-semigroup as theˑundirected simple graphˑ with the vertices are the elementsˑ of and weˑˑstudy the ˑgraph ofˑ equivalence classesˑofˑ which is determinedˑ by theˑ definition equivalenceˑ relation ofˑ these verticesˑ, andˑ then some related ˑproperties areˑ given. Several examples are presented and some theorems are proved. Byˑ usingˑ the definitionˑ ofˑ isomorphicˑ graph, ˑwe showˑ thatˑ the graphˑ of equivalence ˑclasses ˑand the ˑgraphˑof ˑa KU-semigroup ˑ areˑ theˑ sameˑ, in special cases.
In this work, electrodialysis (ED) has been demonstrated to be appropriate technique for reducing the electrical conductivity of real wastewater from fuel washing unit, which has been previously treated by other electrochemical technology (electrocoagulation and electrooxidation). A five cell electrodialysis stack, with an active membrane area of 60 cm2 per cell was employed. During a batch recirculation mode ED system, the effects of parameters such as electrical potential applied (6-18 V) and flow rate of streams (0.5-1.7 L/min.) on the performance of the total dissolved solids (TDS) separation and specific power consumption (SPC) were studied. The results indicate that the process of ED under potential (15 V) and flow
... Show MoreThe current research included palynological study for nine ornamental cultivated species of Asteraceae family. The study included measurement the dimensions of pollen grains and there shape in polar view and equatorial view, sculpturing,colpi length and width, spines length and number of spines rows between colpiand exine thickness, the study showed variations in pollen grains characters forthe studied taxa
External Morphological study of Sympetrum decoloratum Selys of family : Libellulidae from suborder Anisoptera of the order Odonata which were collected from Baghdad Governorate 2011. Such study was included : Detailed description of most body parts (Head, Thorax ,Abdomen and their appendages), with special regard to male genitalia.
AN Salih, LO Hamza, Ann. For. Res, 2022 - Cited by 2
The speech act of refusals has been studied widely either alone or in relation to such areas as apology, requests, promotion, and invitation. The present study aims to investigate the strategies employed by Iraqi females in refusing marriage proposals. It attempts to explore their preferences to respond directly or indirectly in relation to their ages and educational background of the parents. The sample of the study consists of 25 participants; they are learners of English as a foreign language (EFL) at the College of Education for Women/ University of Baghdad. The data are collected by using a discourse completion task (DCT) followed by a follow up interview. The researchers used a Google form shared via emails to get responses from the p
... Show MoreBackground: The integration of modern computer-aided design and manufacturing technologies in diagnosis, treatment planning, and appliance construction is changing the way in which orthodontic treatment is provided to patients. The aim of this study is to assess the validity of digital and rapid prototyped orthodontic study models as compared to their original stone models. Materials and methods: The sample of the study consisted of 30 study models with well-aligned, Angle Class I malocclusion. The models were digitized with desktop scanner to create digital models. Digital files were then converted to plastic physical casts using prototyping machine, which utilizes the fused deposition modeling technology. Polylactic acid polymer was chose
... Show MoreThe increasing requirement and use of dental implant treatments has rendered dental implantology indispensable in dentistry. The aim of this study is to determine the optimum concentration of calcium silicate to be incorporated into a polyetherketoneketone (PEKK) matrix used as an implant material to enhance the bioactivity and mechanical properties of the composite compared with unmodified PEKK. In this study, different weight percentage (wt%) of micro-calcium silicate (m-CS) is incorporated into PEKK with ethanol as a binder. Subsequently, the mixture is dried in a forced convection oven at 120°C and poured into customized molds to fabricate a bioactive composite via compression molding (310°C, 15 MPa, and 20 min holding time
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