Stereo lithography (SLA) three-dimensional (3D) printing process is a type of additive manufacturing techniques that uses digital models from computer-aided design to automatically produce customized 3D objects. Around 30 years, it has been widely utilized in the manufacturing, design, engineering, industrial sectors and its applications in dentistry for manufacturing prosthodontics are very important. The stereo lithography technology is highly regarded because it can produce items with excellent precision especially when selecting the best process parameters. This review article offers a useful and scientific summary of SLA three-dimensional printing technology and its brief history. The specific type of 3D printers which is SLA type based on light curing resin and material overview is also presented. Moreover, the survey was conducted to gain substantial knowledge of the various advantages and disadvantages of SLA 3D printing. According to this study, a summary has been specified on the accuracy of SLA 3D printers and various factors that affected its accuracy and dimension measurement namely layer thickness, normal exposure time, bottom or top exposure time, post processing and room temperature. The majority of works in the literatures conducted till date are on improving the physical part attributes like dimensional accuracy and surface roughness but the improving of the mechanical properties have received less attention and need more focusing in the future works.
The makers of strife exist in every era and time. They differ in how these temptations are created and the methods used in doing so. In our modern era, they are more; This is due to the presence of information technology and its easy availability at their fingertips, as well as the spread of social networking sites, which are rapidly spreading among ignorant groups and groups that are deficient in their use. Which led the makers of sedition to exploit these matters and create various temptations and spread them among peoples and societies. Today, we cannot predict the future of humanity in light of this huge amount of temptation. What the Holy Qur’an mentioned about the types of temptations in its noble verses and their embodiment in seve
... Show MoreAb – initio restricted Hartree - Fock method within the framework of large unit cell (LUC) formalism is used to investigate the electronic structure of Si and Ge nanocrystals. The surface and core properties are investigated. A large unit cell of 8 atoms is used in the present analysis. Cohesive energy, energy gap, conduction and valence band widths are obtained from the electronic structure calculations. The results are compared with available experimental data and theoretical results of other investigators. The calculated lattice constant is found to be slightly larger than the corresponding experimental value because we use only 8 atoms and we compared the results with that of the bulk crystals, nanoclusters are expected to have str
... Show Moreيعد التقطيع الصوري من الاهداف الرئيسة والضرورية في المعالجات الصورية للصور الرقمية، فهو يسعى الى تجزئة الصور المدروسة الى مناطق متعددة اكثر نفعاً تلخص فيها المناطق ذات الافادة لصور الاقمار الصناعية، وهي صور متعددة الاطياف ومجهزة من الاقمار الصناعية باستخدام مبدأ الاستشعار عن بعد والذي اصبح من المفاهيم المهمة التي تُعتمد تطبيقاته في اغلب ضروريات الحياة اليومية، وخاصة بعد التطورات المتسارعة التي شهد
... Show MoreThe current investigation included study of leaf surface epidermis beside indumentum for the species Galium aparine L., G. ceratopodum Boiss, G. setaceum Lam., G. spurium L., and G. tricornatum Dandy, the study showed that paracytic type of stomatal complex is the only type occur in leaf. The indumentum compose of eglandular hairs vary in their apices, length and occurrence of different part of plant body
The study aims to determine the responsibility of nursing staff for medical errors that accompany the surgery at the hospital , which is one of the important issues that the importance of determining the responsibility of landlords nursing medical errors in the hospital was the rationale in choosing the subject. Since study included cases of errors nursing staff of (22) case. While the checklist distributed to a sample of nursing Angel Group in Sadr Teaching Hospital 's (100) nurs According to the problem, the study in determining the responsibility of nursing staff for medical errors that are not important for the hospitals. Has shown results of the study agreement members of the study sample that the clarity of the power posses
... Show MoreTen species of whiteflies (Hemiptera, Aleyrodidae) representing six genera were studied from a collection from different localities in the middle of Iraq. These species are Acaudaleyrodes rachipora (Singh, 1931); Bemisia afer (Priesner and Hosny,1934); Bemisia tabaci (Gennadius, 1889); Dialeurodes citri (Ashmead,1885); Dialeurodes kirkaldy (Kotinsky, 1907); Neomaskellia andropogonis Corbett, 1926; Siphoninus phillyreae (Haliday, 1835); Trialeurodes ricini (Misra, 1924); Trialeurodes vapovariorum (Westwood,1856) and Trialeurodes irakeensis (Al-Malo and Abdul-Rassoul, 2000). Notes are given on their localities, date of c
... Show MoreThe objective of this study is to analyze the difficulties faced by intermediate-level Iraqi students in the use of Spanish unstressed pronouns as a foreign language (ELE). Through a mixed methodology, a descriptive and explanatory analysis was conducted based on written and oral productions of B1-level students at the University of Baghdad.The results show that factors such as interference from the native language (Arabic) and English, as well as grammatical differences between Spanish and Arabic, generate difficulties in the correct use of unstressed pronouns. A contrastive teaching approach is proposed that takes advantage of students' cognitive abilities to highlight similarities and differences between both languages.This stu
... Show MorePraise be to God alone, and after:
This is a research entitled: “A fundamental study of judicial jurisprudence rules and their applications in the Hanbali school of thought,” in which the researcher studied eight legal jurisprudential rules considered by the Hanbalis and others.
At the conclusion of his research, the researcher reached a number of results, including: the importance of taking care of judicial rules, and the need for judges and their assistants to them, including: the need for students of science in Hanbali jurisprudence to study these rules according to the doctrine, and to highlight their applications to them, including: the importance of the rules under study, and their impact on rulings Jurisprudenc
... Show MoreTo approach the problem of individual oppression with an international perspective drawing on Foucauldian concepts, this paper compares George Orwell’s 1984 (1949) and the Iraqi Sinan Antoon’s I’jaam (2004), which was translated into English in 2007. Even though Orwell and Antoon come from dissimilar cultural backgrounds, religions and epochs, they have tackled the issue of individuals’ oppression through their oppressed characters in a strikingly similar way. Hence, by applying the theories of both the American School of Comparative Literature and Foucauldian concepts, the current study attempts to establish a relationship between the Western and Eastern ways of dealing with the issue of oppression as an international problem in au
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