Objectives This work presents laser coating of grade 1 pure titanium (Ti) dental implant surface with sintered biological apatite beta-tricalcium phosphate (β-TCP), which has a chemical composition close to bone. Materials and methods Pulsed Nd:YAG laser of single pulse capability up to 70 J/10 ms and pulse peak power of 8 kW was used to implement the task. Laser pulse peak power, pulse duration, repetition rate and scanning speed were modulated to achieve the most homogenous, cohesive and highly adherent coat layer. Scanning electron microscopy (SEM), energy dispersive X-ray microscopy (EDX), optical microscopy and nanoindentation analyses were conducted to characterise and evaluate the microstructure, phases, modulus of elasticity of the coating layer and calcium-to-phosphate ratio and composition. Results showed that the laser power and scanning speed influenced coating adherence. The cross-sectional field-emission scanning electron microscopy images at low power and high speed showed poor adherence and improved as the laser power increased to 2 kW. Decreasing the scanning speed to 0.2 mm/s at the same power of 2 kW increased adherence. EDX results of the substrate demonstrated that the chemical composition of the coat layer did not change after processing. Moreover, the maps revealed proper distribution of Ca and P with some agglomeration on the surface. The sharp peaks on the X-ray diffraction patterns indicated that β-TCPs in the coat layer were mostly crystalline. The elastic modulus was low at the surface and increased gradually with depth to reach 19 GPa at 200 nm; this value was close to that of bone. The microhardness of the coated substrate increased by about 88%. The laser pulse energy of 8.3 J, pulse peak power of 2 kW, pulse duration of 4.3 min, repetition rate of 10 Hz and scanning speed of 0.2 ms−1 yielded the best results. Conclusion: Both processing and coating have potential use for dental implant applications.
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the research seeks to define the provisions of voluntary charity and some of its contemporary applications, so the research is after the definition of charity and voluntary charity, define the provisions of the Most important thing charity, where the one who is given charity, in the introduction, he talked about the importance of charity in social solidarity,As for the first topic ,it deait with a statement and definition of charity in the Quran,sunnah and comparative juris prudence,whil the second topic was conducted with clarifying the provisions of the ratified, the ratified,while the third topic was concerned with clarifying the application of voluntary charity contemporary investing the Mo
... Show MoreThis research deals with the aesthetics of describing nature and the joys of urban life in the environment of Fatimid Egypt, among a group of poets, who were deceived by its enchanting beauty and breathtaking scenery, through it they depicted the reality of the life they live, and the things that involved them, as well as showing their personal culture, and the joys of life that experience, articulating this with a descriptive and analytical study, focusing on how the poet portrayed the visual scene, in an important stage of Arabic literature in Egypt.
The paper is concerned with a linguistic analysis of the blurbs, used in advertising English and Arabic novels. A blurb is an advertising persuasive text, written on the back cover of a book. Blurbs of selected novels are chosen as representative examples. The selected blurbs belong to two languages, Arabic and English. The paper aims at studying the linguistic features that are characteristic of blurbs as advertising texts and making a sort of comparison between English blurbs and Arabic ones. A linguistic analysis on four levels is presented. Blurbs are tackled from the point of view of four linguistic disciplines that are phonology, syntax, semantics and discourse analysis. A reference is made to the linguistic featu
... Show MoreBackground: Hodgkin's lymphoma (HL), formerly called Hodgkin's diseases is an uncommon form of lymphoma. The incidence of Hodgkin's lymphoma shows marked heterogeneity with respect to age, gender, race, geographic area, social class and histological subtype. This study was carried out in an attempt to evaluate the incidence of Hodgkin's lymphoma of head and neck in Baghdad city. Materials and Methods: The diagnosed cases of Hodgkin's lymphoma of head and neck region in Baghdad city between (1990-1999) were collected and analyzed according to age, gender, site and the histopathological subtypes of the tumor. Results: Out of (702) cases of Hodgkin's lymphoma of ten years between (1990-1999),(362 ) of them were occurred in the head and neck
... Show MoreThis research was based on two pillars. The first is a comparison between of research done and the result of a particular variable of research indebendently in the united state, and second, knowledge and determine the effect of managers practices on the contributions of personnel. The manager and staff are considered to be the most important elements in the organization and all of them have a duty towards the others which governed by the relationship rules of procedure of the ministry researched, on the one hand and the interests of the organization and hence employees , whether executives or employees within management formations that the availability of an acceptable level of good pract
... Show MoreThis study is conducted in order to, investigate the trophic state of Duhok Lake Dam located within Duhok city, Iraq. Water samples are collected seasonally from three monitored sites during 2011. The parameters used for assessing water quality and trophic status level include: water temperature, pH, EC, TDS, DO, BOD5, nutrients, Secchi disk transparency, and chlorophyll a. The results reveal that DO is above 5 mg.l-1 in all sites, BOD5 value is within permissible level for domestic uses. Water quality considered as a hard type. High sulfate concentration is recorded during the study period. Trophic state shows that water type is classified as mesotrophic during autumn season, while it is regarded as eutrophic in other seasons. TDN/TDP rati
... Show MoreBACKGROUND: Vascular tumors are a heterogeneous group of diseases with biological behavior ranging from a hamartomatous growth to frank malignant. The pathophysiology of lymphangioma, vascular malformation and hemangioma is interconnected, blood vessels known to be the site of origin of hamartomas, venous malformations and some neoplasms as benign, tumor-like growth of vessels (hemangiomas). Angiogenesis is the process of formation of new blood vessels from an existing structure.
Aims of study Assessment of angiogenic potential in benign vascular lesions (hemangioma, lymphangioma and lobular capillary hemangioma) of head and neck region.
Materials and Methods: Twenty-two formalin-fixed paraffin-embedd
... Show MoreThis study on the plant of Ain –AL Bason Catharanthus roseous showed the ability of callus cells that is produced by In Vitro culture technique and transformed to the accumulated media (MS 40gm/L sucrose ,2gm/L IAA Indole acetic acid , 0.5gm/L Tryptophan) to produce Vinblastine and Vincristine compounds. Extraction, purification and quantitive determination of Vinblastine and Vincristine compounds using High performance liquid chromatography technique (HPLC)were carried out. The results showed that the highest concentration of Vinblastine and Vincristine compounds were ( 4.653,12.5 (ppm /0.5 dry Wight respectively from transformed callus cells from MS 40 gm /L sucrose , 2 gm / L NAA Naphthaline acetic acid .
هدف البحث التعرف الى اسباب سلوك التنمر لدى طلاب الصف الاول المتوسط من وجهة نظر المدرسين والمدرسات واساليب تعديله، واستعمل الباحثان المنهج الوصفي واختيار عينة عشوائية من المدرسين والمدرسات في متوسطة أرض الرافدين ومتوسطة الرحمن للبنين وكان عددهم (46) مدرساً ومدرسة بواقع (32) مدرساً و(14) مدرسة، واعتمد الباحثان الاستبانة أداة للتعرف الى اسباب سلوك التنمر واساليب تعديله، واشارت نتائج البحث الى تنوع اسباب التن
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